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Sample records for allyl glycidyl ether

  1. SYNTHESIS OF ALLYL PHENYL ETHER AND CLAISEN REARRANGEMENT

    Directory of Open Access Journals (Sweden)

    Gagik Torosyan

    2011-12-01

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

  2. A convenient procedure for the synthesis of allyl and benzyl ethers from alcohols and phenols

    Indian Academy of Sciences (India)

    H Surya Prakash Rao; S P Senthilkumar

    2001-06-01

    Allyl and benzyl ethers of alcohols can be prepared conveniently and in high yield with allyl and benzyl bromide in the presence of solid potassium hydroxide without use of any solvent. Phenols can be converted to allyl ethers but are inert to benzylation under above conditions.

  3. 40 CFR 721.7000 - Polymer of disodium maleate, allyl ether, and ethylene oxide.

    Science.gov (United States)

    2010-07-01

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

  4. 40 CFR 721.7046 - Formaldehyde, polymer with substituted phenols, glycidyl ether.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Formaldehyde, polymer with substituted... New Uses for Specific Chemical Substances § 721.7046 Formaldehyde, polymer with substituted phenols... substance identified as formaldehyde, polymer with substituted phenols, glycidyl ether (PMN P-93-955)...

  5. Synthesis and application of polyepoxide cardanol glycidyl ether as biobased polyepoxide reactive diluent for epoxy resin

    Science.gov (United States)

    Polyepoxide cardanol glycidyl ether (PECGE), a novel cardanol derivative, was synthesized and used as reactive diluent for petroleum-based epoxy resin in this work. The synthetic condition was first optimized, and the resultant PECGE diluent was characterized using Fourier transform infrared spectro...

  6. Regiochemical Control in the Metal-Catalyzed Transposition of Allylic Silyl Ethers

    OpenAIRE

    Hansen, Eric C.; Lee, Daesung

    2006-01-01

    A novel mode of regiochemical control over the allylic [1,3]-transposition of silyloxy groups catalyzed by Re2O7 has been developed. This strategy relies on a cis-oriented vinyl boronate, generated from the Alder ene reaction of homoallylic silyl ethers and alkynyl boronates, to trap out the allylic hydroxyl group. The resulting cyclic boronic acids are excellent partners for cross coupling reactions. High chirality transfer is observed for the rearrangement of enantioenriched allylic silyl e...

  7. Magnetic silica supported palladium catalyst: synthesis of allyl aryl ethers in water

    Science.gov (United States)

    A simple and benign procedure for the synthesis of aryl allyl ethers has been developed using phenols, allyl acetates and magnetically recyclable silica supported palladium catalyst in water; performance of reaction in air and easy separation of the catalyst using an external mag...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-08-01

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

  9. Unusual selectivity-determining factors in the phosphine-free Heck arylation of allyl ethers

    DEFF Research Database (Denmark)

    Ambrogio, I.; Fabrizi, G.; Cacchi, S.;

    2008-01-01

    tolerates a variety of functional groups, including ether, amide, alcohol, aldehyde, ketone, ester, cyano, carboxylic acid, and nitro groups. Ortho-substituted arylating agents afforded moderate yields in some cases, though good to high yields were obtained with o-iodotoluene, iodovanillin, and 1......The Heck reaction of aryl iodides and bromides with allyl ethers has been investigated. Using phosphinefree Pd(OAc)(2) in DNIF at 90 degrees C in the presence of Bu4NOAc, the reaction gave cinnamyl derivatives, usually in good to high yields, with a wide range of aryl halides. The reaction...

  10. Allyl ethers of the 1-alkoxy-2,3-propandiol

    International Nuclear Information System (INIS)

    With the purpose of study of 1-alkoxy-2,3-propandiol allying reaction wasobtained their mono- and diallyl ethers by authors of this article. Theinitial 1-alkoxy-2,3-propandiol was synthesised from mono chlor-hydrin ofglycerin and alcoholates of alcohols of saturated line (C1-C5) and theirisomers

  11. Photo- or EB-induced cross-linking reaction of the polymers containing pendant epoxide or vinyl ether groups from glycidyl vinyl ether

    International Nuclear Information System (INIS)

    Polymers containing pendant epoxide or vinyl ether groups were synthesized by radical copolymerization of glycidyl vinyl ether (GVE) with N-phenylmaleimide (NPM) and N-phenoxycarbonyloxymaleimide (NPCM), or by ring-opening alternating copolymerization of GVE with phthalic anhydride (PAn). In the photo-induced cross-linking reaction, the pendant vinyl ether groups in poly(GVE-PAn) showed higher reactivity than the pendant epoxide groups in poly(GVE-NPM), and poly(GVE-PAn) was readily cross-linked by various dithiols with or without benzophenone. In the electron beam (EB)-induced cross-linking reaction, the sensitivity of poly(GVE-NPCM), which has pendant epoxide and carbonate groups, was higher than that of poly(GVE-NPM) containing only pendant epoxide groups. Furthermore, the EB-sensitivity of poly(GVE-PAn) was even higher than that of poly(GVE-NPM) or poly(GVE-NPCM). (author)

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

    Institute of Scientific and Technical Information of China (English)

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

    2004-01-01

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

  13. Transparent Films from CO2 -Based Polyunsaturated Poly(ether carbonate)s: A Novel Synthesis Strategy and Fast Curing.

    Science.gov (United States)

    Subhani, Muhammad Afzal; Köhler, Burkhard; Gürtler, Christoph; Leitner, Walter; Müller, Thomas E

    2016-04-25

    Transparent films were prepared by cross-linking polyunsaturated poly(ether carbonate)s obtained by the multicomponent polymerization of CO2 , propylene oxide, maleic anhydride, and allyl glycidyl ether. Poly(ether carbonate)s with ABXBA multiblock structures were obtained by sequential addition of mixtures of propylene oxide/maleic anhydride and propylene oxide/allyl glycidyl ether during the polymerization. The simultaneous addition of both monomer mixtures provided poly(ether carbonate)s with AXA triblock structures. Both types of polyunsaturated poly(ether carbonate)s are characterized by diverse functional groups, that is, terminal hydroxy groups, maleate moieties along the polymer backbone, and pendant allyl groups that allow for versatile polymer chemistry. The combination of double bonds substituted with electron-acceptor and electron-donor groups enables particularly facile UV- or redox-initiated free-radical curing. The resulting materials are transparent and highly interesting for coating applications. PMID:27028458

  14. Synthesis of A Novel UV-curable Oligmer 1,4-cyclohexanedimethanol Glycidyl Ether Acrylate and Study on Its UV-curing Properties

    Institute of Scientific and Technical Information of China (English)

    HUANG Biwu; DENG Chong; XU Qinchang; CHEN Weiqing; ZOU Huaihua

    2014-01-01

    A novel UV-curable oligmer 1,4-cyclohexanedimethanol glycidyl ether acrylate (CHDMGEA) was synthesized by utilizing 1,4-cyclohexanedimethanol glycidyl ether (CHDMGE) and acrylic acid (AA) as starting materials, triphenyl phosphine as catalyst and p-hydroxyanisole as inhibitor. The optimum synthetic conditions were that the concentration of triphenyl phosphine was 0.90%of reactants by weight, the concentration of p-hydroxyanisole was 0.20%of reactants by weight, the reaction temperature was 90-100℃, and the molar ratio of CHDMGE to AA was 0.5:1.1. The experimental results show that CHDMGEA is a kind of good UV-curable oligmer. The impact resistance of the UV-cured films with CHDMGEA as oligmer to prepare UV-curing coating was superior to that of the UV-cured films with bisphenol A diglycidyl ether diacrylate (BPGEA) as oligmer to prepare UV-curing coating.

  15. The pure rotational spectrum of a Claisen rearrangement precursor Allyl Phenyl Ether using CP-FTMW spectroscopy

    Science.gov (United States)

    Grubbs, G. S.; Frank, Derek S.; Obenchain, Daniel A.; Cooke, S. A.; Novick, Stewart E.

    2016-06-01

    The pure rotational spectrum of a Claisen rearrangement precursor, Allyl Phenyl Ether (APE), has been measured on a chirped pulse Fourier transform microwave (CP-FTMW) spectrometer in the 8-14 GHz region. Rotational and centrifugal distortion constants for multiple conformations have been determined and are reported for the first time. This is the first study of a phenyl-containing ether where multiple conformers were experimentally observed all within their ground vibrational states. Quantum chemical calculations have been performed to isolate low energy geometries of APE and are implemented to aid in spectral assignment. Other structural parameters such as planar moments and inertial defects for the Allyl Phenyl Ether conformers are presented and compared to similar molecules.

  16. Transparent Films from CO2‐Based Polyunsaturated Poly(ether carbonate)s: A Novel Synthesis Strategy and Fast Curing

    Science.gov (United States)

    Subhani, Muhammad Afzal; Köhler, Burkhard; Gürtler, Christoph; Leitner, Walter

    2016-01-01

    Abstract Transparent films were prepared by cross‐linking polyunsaturated poly(ether carbonate)s obtained by the multicomponent polymerization of CO2, propylene oxide, maleic anhydride, and allyl glycidyl ether. Poly(ether carbonate)s with ABXBA multiblock structures were obtained by sequential addition of mixtures of propylene oxide/maleic anhydride and propylene oxide/allyl glycidyl ether during the polymerization. The simultaneous addition of both monomer mixtures provided poly(ether carbonate)s with AXA triblock structures. Both types of polyunsaturated poly(ether carbonate)s are characterized by diverse functional groups, that is, terminal hydroxy groups, maleate moieties along the polymer backbone, and pendant allyl groups that allow for versatile polymer chemistry. The combination of double bonds substituted with electron‐acceptor and electron‐donor groups enables particularly facile UV‐ or redox‐initiated free‐radical curing. The resulting materials are transparent and highly interesting for coating applications. PMID:27028458

  17. Catalytic Reduction of Noble Metal Salts by Sodium Hypophosphite Promoted by the Film Poly-(p-Allyl Ether Benzenesulfonic Acid).

    Science.gov (United States)

    Costa, M I C F; Steter, J R; Purgato, F L S; Romero, J R

    2011-01-01

    Glassy carbon electrodes were coated with the film poly-(p-allyl ether benzenesulfonic acid) by an anodic procedure. Nickel, platinum, and palladium ions were introduced into the film by ion exchange of H(+) with the corresponding salts. These ions were catalytically reduced to their corresponding metals using the known electroless reducing agent sodium hypophosphite. Scanning electron microcopy and energy dispersive X-ray spectroscopy were carried out to demonstrate the occurrence of the catalytic process. To compare this method with another one carried out in our laboratory, the electrocatalytic reduction of H(+) was studied using the same modified electrodes. A suggested mechanism for the catalysis is proposed. PMID:24052832

  18. SYNTHESIS OF TERMINAL EPOXY FUNCTIONAL SILOXANES FOR MODIFICATION OF DIGLYCIDYL ETHER OF BIS-PHENOL A

    OpenAIRE

    Jenish Paul*,; A. Benny Cherian,

    2015-01-01

    In this study, terminal epoxy functional poly dimethyl siloxanes (TEF PDMS) were synthesized by the hydrosilylation reaction of terminal silyl hydride functional with allyl glycidyl ether. The hydrosilylation reaction was characterized by FTIR and NMR. Samples of modified and unmodified PDMS were blended with commercial epoxy resin, diglycidyl ether of bis-phenol A (DGEBA), at various ratios using a polyamine as curing agent. Their damping and thermal properties were studied by DM...

  19. 腰果酚缩水甘油醚的制备%STUDY ON THE SYNTHESIS OF CARDANOL GLYCIDYL ETHER

    Institute of Scientific and Technical Information of China (English)

    徐丽; 张亚男; 刘国际; 车宋卫

    2013-01-01

    Cardanol glycidyl ether (CGE) was synthesized by using cardanol and epoxy chloropropane as raw materials and Benzyl triethyl ammonium chloride (TEBA) as the catalyst. The process conditions were optimized: n(cardanol):n(epoxy chloropropane):n(sodium hydroxide) =1:6: 3, catalyst amounts was 2%, reaction temperature was 70 ℃ , reaction time was 10 h and the yield of CGE could be up to 89. 1%. The products structures were characterized by FT-IR. Under atmospheric pressure, the density and viscosity of CGE were measured by using the Ostwald-Sprengel-type pyc-nometer and the Ubbelohde capillary viscometer. The results showed that within the given temperature range, both the densities and viscosities would decrease with temperature increasing, and the densities decreased linearly while the viscosities decreased logarithmically.%以腰果酚和环氧氯丙烷为原料,在苄基三乙基氯化铵的催化作用下合成了腰果酚缩水甘油醚.考察了反应条件对产物收率的影响,腰果酚缩水甘油醚的适宜合成工艺条件为:n(腰果酚)∶n(环氧氯丙烷)∶n(氢氧化钠)=1∶6∶3,催化剂用量为2%,反应温度70℃,反应时间10 h,腰果酚缩水甘油醚的产率达到89.1%.利用红外光谱对腰果酚缩水甘油醚进行结构表征.常压下采用比重瓶法和乌氏黏度计法对腰果酚缩水甘油醚的密度和黏度进行测定,结果表明:腰果酚缩水甘油醚的密度在给定温度范围内随着温度的升高呈直线下降,黏度呈对数关系下降.

  20. Synthesis of Oxacyclic Scaffolds via Dual Ruthenium Hydride/Brønsted Acid‐Catalyzed Isomerization/Cyclization of Allylic Ethers

    DEFF Research Database (Denmark)

    Ascic, Erhad; Ohm, Ragnhild Gaard; Petersen, Rico;

    2014-01-01

    A ruthenium hydride/Brønsted acid‐catalyzed tandem sequence is reported for the synthesis of 1,3,4,9‐tetrahydropyrano[3,4‐b]indoles (THPIs) and related oxacyclic scaffolds. The process was designed on the premise that readily available allylic ethers would undergo sequential isomerization, first to...

  1. Catalytic Z-Selective Cross-Metathesis with Secondary Silyl- and Benzyl-Protected Allylic Ethers: Mechanistic Aspects and Applications to Natural Product Synthesis**

    OpenAIRE

    Mann, Tyler J.; Speed, Alexander W. H.; Schrock, Richard R.; Hoveyda, Amir H.

    2013-01-01

    Efficient catalytic cross-metathesis reactions that afford Z-disubstituted allylic silyl or benzyl ethers are reported (see scheme, MAP=monoalkoxide pyrrolide). The approach, in combination with catalytic cross-coupling, provides a general entry to otherwise difficult-to-access alkyne-containing Z olefins.

  2. Synthesis Process of Castor Oil Glycidyl Ether%蓖麻油缩水甘油醚合成工艺研究

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Using castor oil and epoxy chloropropane( ECH) as the main raw materials under the alkali condition, a novel castor oil glycidyl ether ( COGE) was synthesized through two steps, namely open loop and closed loop reaction. The effects of process conditions on epoxy values were investigated. The results showed that the highest epoxy value the product achieved was 1. 56 mmol/g under the condition that the open loop reaction was set at 0. 4% catalyst dosage,3. 5 molar ratio of ECH and castor oil, and reaction temperature at 60 ℃ for 5 h, and as well as the close-loop reaction was set 0. 4% catalyst dosage, 1. 1 molar ratio of NaOH and ECH, and reaction temperature at 60 ℃ for 6 h. The chemical structure of the castor oil glycidyl ether was characterized by FT-IR and 1H NMR. TGA analysis showed that castor oil glycidyl ether had good thermal stability at high temperature. Viscosity test showed that the product could reduce the viscosity of epoxy resin.%以蓖麻油、环氧氯丙烷( ECH)和液碱为主要原料,经二步法开环闭环反应合成了蓖麻油缩水甘油醚( COGE),研究了开环、闭环工艺条件对产物环氧值的影响。结果表明,开环催化剂三氟化硼-二乙基醚用量0.4%,ECH与蓖麻油的物质的量比3.5∶1,反应温度60℃,反应时间5 h;闭环催化剂四甲基氯化铵用量0.4%,反应时间6 h,反应温度60℃,NaOH与ECH物质的量比1.1∶1时产物环氧值最高为1.56 mmol/g。采用红外光谱(FT-IR)、核磁共振氢谱(1H NMR)表征了合成产物的化学结构,热失重(TG)分析表明蓖麻油缩水甘油醚具有优良的高温热稳定性,黏度测试表明该产物可以降低环氧树脂的黏度,加入量15%时,黏度降低46%。

  3. The utilization of the mesoporous Ti-SBA-15 catalyst in the epoxidation of allyl alcohol to glycidol and diglycidyl ether in the water medium

    Directory of Open Access Journals (Sweden)

    Wróblewska Agnieszka

    2015-12-01

    Full Text Available This work presents the studies on the optimization the process of allyl alcohol epoxidation over the Ti-SBA-15 catalyst. The optimization was carried out in an aqueous medium, wherein water was introduced into the reaction medium with an oxidizing agent (30 wt% aqueous solution of hydrogen peroxide and it was formed in the reaction medium during the processes. The main investigated technological parameters were: the temperature, the molar ratio of allyl alcohol/hydrogen peroxide, the catalyst content and the reaction time. The main functions the process were: the selectivity of transformation to glycidol in relation to allyl alcohol consumed, the selectivity of transformation to diglycidyl ether in relation to allyl alcohol consumed, the conversion of allyl alcohol and the selectivity of transformation to organic compounds in relation to hydrogen peroxide consumed. The analysis of the layer drawings showed that in water solution it is best to conduct allyl alcohol epoxidation in direction of glycidol (selectivity of glycidol 54 mol% at: the temperature of 10–17°C, the molar ratio of reactants 0.5–1.9, the catalyst content 2.9–4.0 wt%, the reaction time 2.7–3.0 h and in direction of diglycidyl ether (selectivity of diglycidyl ether 16 mol% at: the temperature of 18–33°C, the molar ratio of reactants 0.9–1.65, the catalyst content 2.0–3.4 wt%, the reaction time 1.7–2.6 h. The presented method allows to obtain two very valuable intermediates for the organic industry.

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

    Directory of Open Access Journals (Sweden)

    Yu Liu

    2015-01-01

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

  5. Preparation and properties of cardanol glycidyl ether%腰果酚基缩水甘油醚的制备及其性能研究

    Institute of Scientific and Technical Information of China (English)

    张俊珩; 闪洁; 秦小玉; 赵婷婷

    2015-01-01

    Reports on the synthesis of cardanol glycidyl ether( CGE )and the hybrid composite of CGE and diglycidyl ether of bisphenol-A( DGEBA). Studied was shown that,the mechanical performance of the CGE/DGEBA blends had maximum with the increase of CGE content. The tensile strength,flexural strength and impact strength of the cured system with 15% CGE can be enhanced respectively about 35 . 4%,43 . 3% and 109 . 5%. The toughness mechanism is the micro-phase separation during curing and sea-island microstructure appearing on the fractured surface.%以腰果酚、环氧氯丙烷为主要原料,制备腰果酚基缩水甘油醚( CGE ),并研究 CGE/双酚 A型环氧树脂( DGEBA)固化物的性能。研究表明,在CGE用量达15%时,环氧树脂固化物的机械性能达到最大值。与纯DGEBA的性能相比,复合材料的拉伸强度、弯曲强度、冲击强度分别提高了35.4%,43.3%和109.5%。随着CGE含量的增加,材料的玻璃化转变温度降低。固化微观相分离和断面出现“海岛”结构是腰果酚基缩水甘油醚的增韧机理。

  6. Effect of fungal mycelia on the HPLC-UV and UV-vis spectrophotometric assessment of mycelium-bound epoxide hydrolase using glycidyl phenyl ether.

    Science.gov (United States)

    Dolcet, Marta M; Torres, Mercè; Canela, Ramon

    2016-06-25

    The use of mycelia as biocatalysts has technical and economic advantages. However, there are several difficulties in obtaining accurate results in mycelium-catalysed reactions. Firstly, sample extraction, indispensable because of the presence of mycelia, can bring into the extract components with a similar structure to that of the analyte of interest; secondly, mycelia can influence the recovery of the analyte. We prepared calibration standards of 3-phenoxy-1,2-propanediol (PPD) in the pure solvent and in the presence of mycelia (spiked before or after extraction) from five fungi (Aspergillus niger, Aspergillus tubingensis, Penicillium aurantiogriseum, Penicillium sp. and Aspergillus terreus). The quantification of PPD was carried out by HPLC-UV and UV-vis spectrophotometry. The manuscript shows that the last method is as accurate as the HPLC method. However, the colorimetric method led to a higher data throughput, which allowed the study of more samples in a shorter time. Matrix effects were evaluated visually from the plotted calibration data and statistically by simultaneously comparing the intercept and slope of calibration curves performed with solvent, post-extraction spiked standards and pre-extraction spiked standards. Significant differences were found between the post- and pre-extraction spiked matrix-matched functions. Pre-extraction spiked matrix-matched functions based on A. tubingensis mycelia, selected as the reference, were validated and used to compensate for low recoveries. These validated functions were successfully applied to the quantification of PPD achieved during the hydrolysis of glycidyl phenyl ether by mycelium-bound epoxide hydrolases and equivalent hydrolysis yields were determined by HPLC-UV and UV-vis spectrophotometry. This study may serve as starting point to implement matrix effects evaluation when mycelium-bound epoxide hydrolases are studied. PMID:26902669

  7. Novel Finding of Widespread Occurrence and Accumulation of Bisphenol A Diglycidyl Ethers (BADGEs) and Novolac Glycidyl Ethers (NOGEs) in Marine Mammals from the United States Coastal Waters.

    Science.gov (United States)

    Xue, Jingchuan; Kannan, Kurunthachalam

    2016-02-16

    Bisphenol A diglycidyl ether (BADGE)- and bisphenol F diglycidyl ether (BFDGE)-based epoxy resins have a broad range of applications, including serving as inner coatings of food and beverage cans and as protective coatings in marine construction. Prior to this study, no studies had examined the occurrence and bioaccumulation of BADGEs or BFDGEs in aquatic organisms. In this study, BADGE, BFDGE, and nine of their derivatives were determined in 121 tissue (liver, kidney, blubber, and brain) samples from eight species of marine mammals collected from the U.S. coastal waters of Florida, California, Washington, and Alaska. BADGE·2HCl was the predominant compound found in the majority (78.5%) of the marine mammal tissues analyzed, at concentrations of up to 2950 ng/g (wet weight (wt)) found in the liver of a sea otter from Kachemak Bay, Alaska. The measured concentrations of BADGE·2HCl in marine mammals were on the order of hundreds of nanograms per gram tissue, which are some of the highest concentrations ever reported for this compound in biota. Males contained greater concentrations of BADGE·2HCl than did females. BADGE·2HCl also was found in the brain tissues of sea otters. Trace levels of BADGE·2HCl were found in the livers of polar bears from Alaska, which suggested that BADGEs are widely distributed in the oceanic environment. PMID:26800265

  8. Ruthenium Catalyzed Diastereo- and Enantioselective Coupling of Propargyl Ethers with Alcohols: Siloxy-Crotylation via Hydride Shift Enabled Conversion of Alkynes to π-Allyls.

    Science.gov (United States)

    Liang, Tao; Zhang, Wandi; Chen, Te-Yu; Nguyen, Khoa D; Krische, Michael J

    2015-10-14

    The first enantioselective carbonyl crotylations through direct use of alkynes as chiral allylmetal equivalents are described. Chiral ruthenium(II) complexes modified by Josiphos (SL-J009-1) catalyze the C-C coupling of TIPS-protected propargyl ether 1a with primary alcohols 2a-2o to form products of carbonyl siloxy-crotylation 3a-3o, which upon silyl deprotection-reduction deliver 1,4-diols 5a-5o with excellent control of regio-, anti-diastereo-, and enantioselectivity. Structurally related propargyl ethers 1b and 1c bearing ethyl- and phenyl-substituents engage in diastereo- and enantioselective coupling, as illustrated in the formation of adducts 5p and 5q, respectively. Selective mono-tosylation of diols 5a, 5c, 5e, 5f, 5k, and 5m is accompanied by spontaneous cyclization to deliver the trans-2,3-disubstituted furans 6a, 6c, 6e, 6f, 6k, and 6m, respectively. Primary alcohols 2a, 2l, and 2p were converted to the siloxy-crotylation products 3a, 3l, and 3p, which upon silyl deprotection-lactol oxidation were transformed to the trans-4,5-disubstituted γ-butyrolactones 7a, 7l, and 7p. The formation of 7p represents a total synthesis of (+)-trans-whisky lactone. Unlike closely related ruthenium catalyzed alkyne-alcohol C-C couplings, deuterium labeling studies provide clear evidence of a novel 1,2-hydride shift mechanism that converts metal-bound alkynes to π-allyls in the absence of intervening allenes. PMID:26418572

  9. Cationic ruthenium-cyclopentadienyl-diphosphine complexes as catalysts for the allylation of phenols with allyl alcohol: relation between structure and catalytic performance in O- vs. C-allylation

    NARCIS (Netherlands)

    van Rijn, J.A.; Lutz, M.; von Chrzanowski, L.S.; Spek, A.L.; Bouwman, E.; Drent, E.

    2009-01-01

    A new catalytic method has been investigated to obtain either O- or C-allylated phenolic products using allyl alcohol or diallyl ether as the allyl donor. With the use of new cationic ruthenium(II) complexes as catalyst, both reactions can be performed with good selectivity. Active cationic Ru(II) c

  10. 活性稀释剂苄基缩水甘油醚丙烯酸酯的合成及性能表征%Synthesis and Characterization of a New Type Reactive Diluent-benzyl Glycidyl Ether Acrylate

    Institute of Scientific and Technical Information of China (English)

    翁子骧; 黄笔武; 郑雪琳; 姜安坤

    2011-01-01

    本文以苄基缩水甘油醚和丙烯酸为原料合成活性稀释剂苄基缩水甘油醚丙烯酸酯(BGEA),研究了反应温度、催化剂和阻聚剂用量对反应的影响.结果表明最佳的反应条件为:反应温度110℃左右,催化剂N,N'-二甲基苄胺质量分数为0.9%,阻聚剂对甲氧基苯酚质量分数为0.2%.后将BGEA作为稀释剂加入到双酚A型环氧丙烯酸树脂中配制成光固化涂料,利用TG、AFM等表征手段对光固化膜的热性能、表面形貌及物理机械性能进行研究.%This article studied the effects of reaction temperature, the selection of catalyst and inhibitor on the synthesis of BGEA from benzyl glycidyl ether and acrylic acid, the product of which was characterized by FTIR. Experimental results show that the best reaction temperature was 110 ℃, the best mass fraction of catalyzer and inhibitor was 0. 9% and 0. 2% respectively. The UV-curing coating was prepared with adding BGEA to bisphenol A type epoxy diacrylate, and the properties of its cured film were investigated by using TG, AFM etc.

  11. The unsaturated simple ethers of glycerin

    International Nuclear Information System (INIS)

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

  12. Synthesis and Properties of Biobased Epoxy Resins. Part 1. Glycidylation of Flavonoids by Epichlorohydrin

    OpenAIRE

    Nouailhas, Hélène; Aouf, Chahinez; Le Guernevé, Christine; CAILLOL, Sylvain; Boutevin, Bernard; Fulcrand-Hoh, Helene,

    2011-01-01

    Biobased epoxy resins were synthesized from a catechin molecule, one of the repetitive units in natural flavonoid biopolymers also named condensed tannins. The reactivity of catechin toward epichlorohydrin to form glycidyl ether derivatives was studied using two model compounds, resorcinol and 4-methylcatechol, which represent the A and B rings of catechin, respectively. These model molecules clearly showed differences in reactivity upon glycidylation, explaining the results found with catech...

  13. Propenyl ether monomers for photopolymerization

    Science.gov (United States)

    Crivello, James V.

    1996-01-01

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

  14. Preparation and characterization of 1,4-cyclohexanedimethanol glycidyl ether by cationic type UV-curing prepolymer%1,4-环己烷二甲醇二缩水甘油醚的制备及作为阳离子型紫外光固化预聚物性能

    Institute of Scientific and Technical Information of China (English)

    徐钦昌; 黄笔武; 刘世民; 杨志宏; 谌伟庆

    2013-01-01

    以三氟化硼乙醚络合物为催化剂,以氢氧化钠为成环反应的闭环剂,利用1,4-环己烷二甲醇(CHDM)和环氧氯丙烷(ECH)为原料合成了1,4-环己烷二甲醇二缩水甘油醚(CHDMGE).研究了催化剂三氟化硼乙醚络合物用量、ECH和CHDM摩尔比,以及成环反应温度这些因素对其合成反应的影响,结果表明较好的合成反应条件是三氟化硼乙醚络合物质量分数为CHDM和ECH总量的0.40%,ECH和CHDM较佳摩尔比为3.6∶1.0,NaOH和CHDM较佳摩尔比为2.8∶1.0,以及较佳的成环反应温度为30℃.同时,把三芳基锍鎓六氟锑酸盐作为引发剂,加入到CHDMGE中制备了阳离子型紫外光固化树脂,其紫外光固化膜的拉伸强度36.59 MPa,杨氏模量1264.52 MPa,断裂伸长率7.16%.%1,4-cyclohexanedimethanol glycidyl ether(CHDMGE) was synthesized with 1,4-cyclohexanedimethanol(CHDM) and epichlorohydrin(ECH) as raw materials,using boron trifluoride ether complex as the catalyst,and sodium hydroxide as the closing ring agent.The closing ring temperature,the dosage of the catalyst,and the moral ratio of ECH to CHDM were optimized.The optimal synthesizing conditions are 0.40% of the catalyst mass fraction,3.6/1.0 as the ratio of ECH/CHDM,2.8/1.0 as the ratio of NaOH/CHDM,and the closed ring reaction temperature 30 ℃.Meanwhile,the cationic type UV-curing coating was prepared with CHDMGE and triphenylsulphonium hexafluoroantimonate (UVI-6976).The mechanical properties of the UV-cured films were determined,giving 36.59MPa of tensile strength,1264.52MPa of Young's modulus and 7.16 %of elongation at tear.

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

    Institute of Scientific and Technical Information of China (English)

    邓冲; 黄笔武; 周宽; 程桂亮; 胡秋发; 谌伟庆

    2013-01-01

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

  16. 超高效液相色谱-串联质谱法同时测定鱼、肉类罐头食品中的BADGE、NOGE及其衍生物%Determination of Bisphenol a Diglycidyl Ether (BADGE), Novolac Glycidyl Ethers(NOGE) and Its Derivatives in Canned Fish and Meat by Ultra-performance Liquid Chromatography with Tandem Mass Spectrometry

    Institute of Scientific and Technical Information of China (English)

    林赛君; 陈思; 薛鸣; 张虹

    2011-01-01

    An ultra-performance liquid chromatography with tandem mass spectrometry method for determination of bisphenol A diglycidyl ether (BADGE) , novolac glycidyl ether (NOGE) and its derivatives from canned food has been developed. The proposed method includes microwave-assisted extraction followed by puri? cation by solid phase extraction (SPE). After separation by BEH Cls ( column 100 mm ×2.1 mm, 1.7 μm), the sample was detected by API 4000 - QTRAP mass spectrometry under positive electrospray ionization mode, with acetonitrile and 0.2% aqueous formic acid as mobile phase. The detection limits were 0. 010 2 - 0. 197 2 ng/g, and recoveries at three different concentrations ranged from 65.7% to 99. 1%. This method was successfully applied to canned fish and meat, the highest total contents of 3 -6 R-NOGE reached 209.03 mg/6 dm2.%建立了一种罐头食品中的BADGE(bisphenol A diglycidyl ether,双酚A-二环氧甘油醚)、NOGE(novolac glycidyl ether,酚醛清漆甘油醚)及其衍生物含量的超高效液相色谱-串联质谱检测法。前处理包括正己烷/丙酮微波辅助萃取,Varain-PS-DVB固相萃取柱净化等。样品经BEH C18色谱柱(100mm×2.1mm,1.7μm)分离,以乙腈和0.2%甲酸水为流动相,进行梯度洗脱,在API4000-Q TRAP质谱仪电喷雾正离子、多反应监测(MRM)模式下进行检测。分析物检出限达到0.0102ng/g到0.1972ng/g,三水平加标回收率在65.7%~99.1%。

  17. 40 CFR 721.2950 - Carboxylic acid glycidyl esters.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Carboxylic acid glycidyl esters. 721... Substances § 721.2950 Carboxylic acid glycidyl esters. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified generically as carboxylic acid glycidyl...

  18. Nouvelles Réactions d'Allylation Radicalaire : Exploitation de la Rupture homolytique de Liaisons Carbone-Oxygène et Carbone-Carbone

    OpenAIRE

    Debien, Laurent

    2013-01-01

    This PhD thesis is divided in eight chapters. The first three bibliographic chapters present the general principles of radical chemistry, the possibility offered by the xanthate radical chemistry and a review of the radical allylation methods, main focus of this work. The three next chapters are dedicated to the exploitation of the radical allylation of allylic alcohols, recently discovered in our laboratory. The use of such a technology enabled the preparation of functionalized enol ethers, ...

  19. Catalytic rearrangement of the chloroallyl ethers of p-cresol

    International Nuclear Information System (INIS)

    The rearrangement of a series of p-cresol ethers (β- and γ-chloro-, βγ- and βγ,γ-trichloroallyl), catalyzed by boron trifluoride etherate, was studied. Increase in the number of chlorine atoms in the allyl unit of the ether hinders the rearrangement, and its mechanism changes in the investigated series of ethers from intramolecular [3,3]-sigmatropic (with inversion of the allyl unit) to intermolecular, which corresponds to electrophilic substitution in the aromatic ring (without inversion). The presence of the chlorine atom at the β position of the allyl unit promotes rearrangement by a concerted intramolecular mechanism, while a chlorine atom at the γ position promotes rearrangement by an intermolecular stage mechanism. Two chlorine atoms at the γ position give rise mainly to the intermolecular rearrangement path

  20. Mild and Site-Selective Allylation of Enol Carbamates with Allylic Carbonates under Rhodium Catalysis.

    Science.gov (United States)

    Sharma, Satyasheel; Han, Sang Hoon; Oh, Yongguk; Mishra, Neeraj Kumar; Han, Sangil; Kwak, Jong Hwan; Lee, Seok-Yong; Jung, Young Hoon; Kim, In Su

    2016-03-18

    The rhodium(III)-catalyzed mild and site-selective C-H allylation of enol carbamates with 4-vinyl-1,3-dioxolan-2-one and allylic carbonates affords allylic alcohols and terminal allylated products, respectively. The assistance of the carbamoyl directing group provides a straightforward preparation of biologically and synthetically important allylated enol carbamates. PMID:26906724

  1. Ring-opening of cyclic ethers with carbon–carbon bond formation by Grignard reagents

    DEFF Research Database (Denmark)

    Christensen, Stig Holden; Holm, Torkil; Madsen, Robert

    2014-01-01

    allyl- and benzylmagnesium halides when the ether was tetrahydrofuran or 3,3-dimethyloxetane. Lower yields were obtained with substituted tetrahydrofurans while no ring-opening was observed with tetrahydropyran. Only highly reactive allyl and benzyl Grignard reagents participated in the transformation...... while no reaction occurred with other alkylmagnesium halides....

  2. A Comparative 90 Day Toxicity Study of Allyl Acetate, Allyl Alcohol and Acrolein

    OpenAIRE

    Auerbach, Scott S.; Mahler, Joel; Travlos, Gregory S.; Irwin, Richard D

    2008-01-01

    Allyl acetate (AAC), allyl alcohol (AAL), and acrolein (ACR) are used in the manufacture of detergents, plastics, pharmaceuticals, and chemicals and as agricultural agents. A metabolic relationship exists between these chemicals in which allyl acetate is metabolized to allyl alcohol and subsequently to the highly reactive,α,β-unsaturated aldehyde, acrolein. Due to the weaker reactivity of the protoxicants, allyl acetate and allyl alcohol, relative to acrolien we hypothesized the protoxicants ...

  3. Branching Out: Rhodium-Catalyzed Allylation with Alkynes and Allenes.

    Science.gov (United States)

    Koschker, Philipp; Breit, Bernhard

    2016-08-16

    We present a new and efficient strategy for the atom-economic transformation of both alkynes and allenes to allylic functionalized structures via a Rh-catalyzed isomerization/addition reaction which has been developed in our working group. Our methodology thus grants access to an important structural class valued in modern organic chemistry for both its versatility for further functionalization and the potential for asymmetric synthesis with the construction of a new stereogenic center. This new methodology, inspired by mechanistic investigations by Werner in the late 1980s and based on preliminary work by Yamamoto and Trost, offers an attractive alternative to other established methods for allylic functionalization such as allylic substitution or allylic oxidation. The main advantage of our methodology consists of the inherent atom economy in comparison to allylic oxidation or substitution, which both produce stoichiometric amounts of waste and, in case of the substitution reaction, require prefunctionalization of the starting material. Starting out with the discovery of a highly branched-selective coupling reaction of carboxylic acids with terminal alkynes using a Rh(I)/DPEphos complex as the catalyst system, over the past 5 years we were able to continuously expand upon this chemistry, introducing various (pro)nucleophiles for the selective C-O, C-S, C-N, and C-C functionalization of both alkynes and the double-bond isomeric allenes by choosing the appropriate rhodium/bidentate phosphine catalyst. Thus, valuable compounds such as branched allylic ethers, sulfones, amines, or γ,δ-unsaturated ketones were successfully synthesized in high yields and with a broad substrate scope. Beyond the branched selectivity inherent to rhodium, many of the presented methodologies display additional degrees of selectivity in regard to regio-, diastereo-, and enantioselective transformations, with one example even proceeding via a dynamic kinetic resolution. Many advances

  4. Synthesis of allyl dimethyl dehydroabietyl ammonium chloride and its surface activities

    International Nuclear Information System (INIS)

    Allyl dimethyl dehydroabietyl ammonium chloride (ADMDHAC) was synthesized from dehydroabietylamine (DHA) and allyl chloride. The synthesis was carried out in two steps. First, DHA was transformed into N,N-dimethyl dehydroabietyl amine (DMDHA) through Eschweiler-Clarke Reaction. Second, the ADMDHAC was obtained after the DMDHA had reacted with allyl chloride and recrystallized using a solvent composed of diethyl ether and ethanol. Critical micelle concentrations (cmc) of ADMDHAC at 25 degree C was found to be 2.851*10-4 mol.L-1, and its surface tension value at cmc (gamma cmc) was determined to be 30.6 mN.m-1, these data suggested that ADMDHAC could be used as a good alternative of benzalkonium chloride (BC). (author)

  5. The allylic chalcogen effect in olefin metathesis

    Directory of Open Access Journals (Sweden)

    Yuya A. Lin

    2010-12-01

    Full Text Available Olefin metathesis has emerged as a powerful tool in organic synthesis. The activating effect of an allylic hydroxy group in metathesis has been known for more than 10 years, and many organic chemists have taken advantage of this positive influence for efficient synthesis of natural products. Recently, the discovery of the rate enhancement by allyl sulfides in aqueous cross-metathesis has allowed the first examples of such a reaction on proteins. This led to a new benchmark in substrate complexity for cross-metathesis and expanded the potential of olefin metathesis for other applications in chemical biology. The enhanced reactivity of allyl sulfide, along with earlier reports of a similar effect by allylic hydroxy groups, suggests that allyl chalcogens generally play an important role in modulating the rate of olefin metathesis. In this review, we discuss the effect of allylic chalcogens in olefin metathesis and highlight its most recent applications in synthetic chemistry and protein modifications.

  6. Regioselective hydroformylation of allylic alcohols.

    Science.gov (United States)

    Lightburn, Thomas E; De Paolis, Omar A; Cheng, Ka H; Tan, Kian L

    2011-05-20

    A highly regioselective hydroformylation of allylic alcohols is reported toward the synthesis of β-hydroxy-acid and aldehyde products. The selectivity is achieved through the use of a ligand that reversibly binds to alcohols in situ, allowing for a directed hydroformylation to occur. The application to trisubstituted olefins was also demonstrated, which yields a single diastereomer product consistent with a stereospecific addition of CO and hydrogen. PMID:21504208

  7. Regioselective Hydroformylation of Allylic Alcohols

    Science.gov (United States)

    Lightburn, Thomas E.; De Paolis, Omar A.; Cheng, Ka H.; Tan, Kian L.

    2011-01-01

    A highly regioselective hydroformylation of allylic alcohols is reported towards the synthesis of β-hydroxy-acid and aldehyde products. The selectivity is achieved through the use of a ligand that reversibly binds to alcohols in situ, allowing for a directed hydroformylation to occur. The application to trisubstituted olefins was also demonstrated, which yields a single diastereomer product consistent with a stereospecific addition of CO and hydrogen. PMID:21504208

  8. Interplay of metal-allyl and metal-metal bonding in dimolybdenum allyl complexes.

    Energy Technology Data Exchange (ETDEWEB)

    Trovitch, R. J.; John, K. D.; Martin, R. L.; Obrey, S. J.; Sattelberger, A. P.; Scott, B. L.; Baker, R. T.; LANL; Univ. of Ottawa

    2009-01-01

    Addition of PMe{sub 3} to Mo{sub 2}(allyl){sub 4} afforded Mo{sub 2}(allyl){sub 4}(PMe{sub 3}){sub 2}, in which two of the allyl groups adopt an unprecedented {mu}{sub 2}-{eta}{sup 1}, {eta}{sup 3} bonding mode; theoretical studies elucidate the roles of the {sigma}- and {pi}-donor ligands in the interplay of metal-allyl and metal-metal bonding.

  9. MOLECULAR MUTAGENESIS INDUCED BY GLYCIDYL METHACRYLATE

    Institute of Scientific and Technical Information of China (English)

    高惠兰; 左谨; 谢大英; 方福德

    1994-01-01

    Glycidyl methacrylate(GMA)is a recently recognized mutagen.In order to explore the mutagenicity and mechanism of GMA,plasmid pBR322 was used for in vitro binding,mutant screening,restriction enzyme map-ping,and DNA sequencing.To explore the mechanism by which an initial premutational event is converted into a stable heritable mutation,pBR322 and GMA-bound pBR322 were transformed into E.coli HB101,and the follow-ing results were obtainge:1)GMA-bound pBR322 induced phenotype changes in competent cells.Two stable and heritable mutants were isolated (ApRTcS and ApSTcR).2)When restriction enzyme mapping was used to analyze the mutant ApRTcS,four of seven maps showed changes,but no large DNA insertion or deletion were observed.3)The frequency of deletion and insertion forms counted about 10%.Sequence specificity and hot spot regions were evident in the sequence analysis of mutated plasmid.The above results indicate that the premutagenic lesions of plasmid induced by GMA can be converted into point mutatons in vivo.

  10. Catalytic deallylation of allyl- and diallylmalonates.

    Science.gov (United States)

    Necas, David; Turský, Matyás; Kotora, Martin

    2004-08-25

    Substituted allylmalonates undergo the selective C-C bond cleavage in the presence of triethylaluminum and a catalytic amount of nickel and ruthenium phosphine complexes, resulting in the loss of the allyl moiety and formation of monosubstituted malonates. Comparison of reactivity of the nickel and ruthenium complexes showed that the use of the former is general with respect to the structure of the substituted allylmalonates, and the activity of the latter depended on the substitution pattern of the double bond of the allylic moiety. The smooth deallylation may encourage the use of the allyl group as a protective group for the acidic hydrogen in malonates. PMID:15315416

  11. Highly enantio- and diastereoselective allylic alkylation of Morita-Baylis-Hillman carbonates with allyl ketones

    KAUST Repository

    Tong, Guanghu

    2013-05-17

    The asymmetric allylic alkylation of Morita-Baylis-Hillman (MBH) carbonates with allyl ketones has been developed. The α-regioselective alkylation adducts, containing a hexa-1,5-diene framework with important synthetic value, were achieved in up to 83% yield, >99% ee, and 50:1 dr by using a commercially available Cinchona alkaloid as the catalyst. From the allylic alkylation adduct, a cyclohexene bearing two adjacent chiral centers was readily prepared. © 2013 American Chemical Society.

  12. Novel fluorescent poly(glycidyl methacrylate) - silica microspheres

    Czech Academy of Sciences Publication Activity Database

    Grama, Silvia; Boiko, N.; Bilyy, R.; Klyuchivska, O.; Antonyuk, V.; Stoika, R.; Horák, Daniel

    2014-01-01

    Roč. 56, July (2014), s. 92-104. ISSN 0014-3057 R&D Projects: GA MŠk EE2.3.30.0029; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61389013 Keywords : microspheres * silica * poly(glycidyl methacrylate) Subject RIV: CE - Biochemistry Impact factor: 3.005, year: 2014

  13. Glycidyl Azide Polymer-based Enhanced Energy LOVA Gun Propellant

    OpenAIRE

    R. R. Sanghavi; P. J. Kamale; M.A.R. Shaikh; T. K. Chakraborthy; S. N. Asthana; Amarjit Singh

    2006-01-01

    In this study, cyclotrimethylene trinitramine propellants with triacetin (TA)-plasticisedcellulose acetate (CA) and nitrocellulose (NC) combination as binders were evaluated for lowvulnerable ammunition (LOVA). Triacetin was replaced by energetic plasticiser; glycidyl azidepolymer (GAP) in increments to enhance the performance in terms of force constant . In additionto ballistics, parameters like vulnerability, mechanical and thermal properties of GAP-basedpropellants in comparison to those o...

  14. N-Allylation of amines with allyl acetates using chitosan-immobilized palladium

    Science.gov (United States)

    A simple procedure for N-Allylation of allyl Acetates has been developed using a biodegradable and easily recyclable heterogeneous chitosan-supported palladium catalyst. The general methodology, applicable to wide range of substrates, has sustainable features that include a ligan...

  15. Compound list: allyl alcohol [Open TG-GATEs

    Lifescience Database Archive (English)

    Full Text Available allyl alcohol AA 00010 ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Human/in_vitro/allyl_alcohol....Human.in_vitro.Liver.zip ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vitro/allyl_alcohol...dbc.jp/archive/open-tggates/LATEST/Rat/in_vivo/Liver/Repeat/allyl_alcohol.Rat.in_vivo.Liver.Repeat.zip ftp:/.../ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vivo/Kidney/Single/allyl_alcohol.Rat.in_vivo.Kidney....Single.zip ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vivo/Kidney/Repeat/allyl_alcohol.Rat.in_vivo.Kidney.Repeat.zip ...

  16. Synthesis and characterization of magnetic poly(glycidyl methacrylate) microspheres

    Science.gov (United States)

    Horák, Daniel; Petrovský, Eduard; Kapička, Aleš; Frederichs, Theodor

    2007-04-01

    Magnetic nanoparticles encapsulated in poly(glycidyl methacrylate) microspheres were prepared and their detailed structural and magnetic characteristics given. Iron oxide nanoparticles were obtained by chemical coprecipitation of Fe(II) and Fe(III) salts and stabilized with dextran, (carboxymethyl)dextran or tetramethylammonium hydroxide. The microspheres were prepared by emulsion or dispersion polymerization of glycidyl methacrylate in the presence of ferrofluid. The microspheres were uniform both in shape and usually also in size; their size distribution was narrow. All the magnetic parameters confirm superparamagnetic nature of the microspheres. Blocking temperature was not observed, suggesting the absence of magnetic interactions at low temperatures. This is most probably caused by complete encapsulation and the absence of agglomeration. Such microspheres can be used in biomedical applications.

  17. Synthesis and characterization of magnetic poly(glycidyl methacrylate) microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Horak, Daniel [Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovskeho Sq. 2, 162 06 Prague 6 (Czech Republic)]. E-mail: horak@imc.cas.cz; Petrovsky, Eduard [Geophysical Institute, Academy of Sciences of the Czech Republic, Bocni II/1401, 141 31 Prague 4 (Czech Republic); Kapicka, Ales [Geophysical Institute, Academy of Sciences of the Czech Republic, Bocni II/1401, 141 31 Prague 4 (Czech Republic); Frederichs, Theodor [University of Bremen, Department of Geosciences, GEO I, Klagenfurter Strasse, 28359 Bremen (Germany)

    2007-04-15

    Magnetic nanoparticles encapsulated in poly(glycidyl methacrylate) microspheres were prepared and their detailed structural and magnetic characteristics given. Iron oxide nanoparticles were obtained by chemical coprecipitation of Fe(II) and Fe(III) salts and stabilized with dextran, (carboxymethyl)dextran or tetramethylammonium hydroxide. The microspheres were prepared by emulsion or dispersion polymerization of glycidyl methacrylate in the presence of ferrofluid. The microspheres were uniform both in shape and usually also in size; their size distribution was narrow. All the magnetic parameters confirm superparamagnetic nature of the microspheres. Blocking temperature was not observed, suggesting the absence of magnetic interactions at low temperatures. This is most probably caused by complete encapsulation and the absence of agglomeration. Such microspheres can be used in biomedical applications.

  18. Magnetic poly(glycidyl methacrylate) microspheres for protein capture

    Czech Academy of Sciences Publication Activity Database

    Koubková, Jana; Müller, P.; Hlídková, Helena; Plichta, Zdeněk; Proks, Vladimír; Vojtěšek, B.; Horák, Daniel

    2014-01-01

    Roč. 31, č. 5 (2014), s. 482-491. ISSN 1871-6784 R&D Projects: GA ČR GCP207/12/J013; GA MŠk 7E12053 EU Projects: European Commission(XE) 246513 - NADINE Institutional support: RVO:61389013 Keywords : glycidyl methacrylate * microspheres * protein p53 Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.898, year: 2014

  19. Transition‐Metal‐Free Borylation of Allylic and Propargylic Alcohols

    Science.gov (United States)

    Miralles, Núria; Alam, Rauful

    2016-01-01

    Abstract The base‐catalyzed allylic borylation of tertiary allylic alcohols allows the synthesis of 1,1‐disubstituted allyl boronates, in moderate to high yield. The unexpected tandem performance of the Lewis acid–base adduct, [Hbase]+[MeO‐B2pin2]− favored the formation of 1,2,3‐triborylated species from the tertiary allylic alcohols and 1‐propargylic cyclohexanol at 90 °C. PMID:26934578

  20. Transition-Metal-Free Borylation of Allylic and Propargylic Alcohols.

    Science.gov (United States)

    Miralles, Núria; Alam, Rauful; Szabó, Kálmán J; Fernández, Elena

    2016-03-18

    The base-catalyzed allylic borylation of tertiary allylic alcohols allows the synthesis of 1,1-disubstituted allyl boronates, in moderate to high yield. The unexpected tandem performance of the Lewis acid-base adduct, [Hbase](+) [MeO-B2 pin2 ](-) favored the formation of 1,2,3-triborylated species from the tertiary allylic alcohols and 1-propargylic cyclohexanol at 90 °C. PMID:26934578

  1. Enantioselective synthesis of fluorinated branched allylic compounds via Ir-catalyzed allylations of functionalized fluorinated methylene derivatives.

    Science.gov (United States)

    Zhang, Hongbo; Chen, Jiteng; Zhao, Xiao-Ming

    2016-08-14

    Enantioselective introduction of the functionalized monofluorinated methylenes into the allylic fragment under Ir catalysis has been realized, which gave the fluorinated branched allyl products in good to high yields with excellent regio- and enantioselectivities. PMID:27383920

  2. Kinetic Resolution of Racemic and Branched Monosubstituted Allylic Acetates by a Ruthenium-Catalyzed Regioselective Allylic Etherification.

    Science.gov (United States)

    Shinozawa, Toru; Terasaki, Shou; Mizuno, Shota; Kawatsura, Motoi

    2016-07-01

    We demonstrated the kinetic resolution of racemic and branched monosubstituted allylic acetates by a ruthenium-catalyzed regioselective allylic etherification. The reaction was effectively catalyzed by the chiral ruthenium catalyst, which was generated by [RuCl2(p-cymene)]2 and (S,S)-iPr-pybox and a catalytic amount of TFA, and both the allylic etherification product and recovered allylic acetate were obtained as an enantiomerically enriched form with up to a 103 s value. PMID:27276556

  3. Relationships of isomerization of the allylic type

    Energy Technology Data Exchange (ETDEWEB)

    Levanova, S.V.; Yanshevskaya, I.V.; Asatryan, E.M.; Saakyan, N.L.; Kostand' yan, V.A.; Malkhasyan, A.Ts.; Martirosyan, G.T.

    1986-10-10

    The authors report the results of thermodynamic and kinetic studies of allylic rearrangement of dichlorobutenes. Allylic rearrangements were studied in a thermo-stated glass flask fitted with a stirrer, with the use of various (with respect to total DCB) original mixtures of the three isomers. A solution of copper naphthenate in solvent naphtha, containing 5% Cu, was used as the catalyst. The reaction mixture was analyzed periodically with the aid of the LKhM-8MD chromatograph, using a column 3000 x 3 mm packed with 5% of Apiezone and 5% of polyethylene glycol on Chromosorb W. The operating temperature was 120/sup 0/.

  4. Allylic Nitro Compounds as Nitrite Donors

    OpenAIRE

    Chakrapani, Harinath; Gorczynski, Michael J.; King, S Bruce

    2006-01-01

    Allylic nitro compounds were synthesized and evaluated as organic sources of nitrite and nitric oxide. Unactivated allylic nitro compounds do not spontaneously release nitrite and nucleophile promoted nitrite release is slow. However, 2-(nitromethyl)-cyclohex-1-ene-3-one spontaneously dissociates in buffer (pH = 7.4) to release nitrite with a kobs = 1.6 × 10−5 s−1. In the presence of L-cysteine, this compound rapidly yields nitrite and reacts with hemoglobin similarly to sodium nitrite. Struc...

  5. An XPS study of pulsed plasma polymerised allyl alcohol film growth on polyurethane

    International Nuclear Information System (INIS)

    The growth of highly functionalised poly allyl alcohol films by pulsed plasma polymerisation of CH2 =CHCH2OH on biomedical grade polyurethane has been followed by X-ray photoelectron spectroscopy (XPS) and contact angle measurements. Film thickness is observed to increase approximately linearly with plasma modification time, suggesting a layer-by-layer growth mode of poly allyl alcohol. Water contact angle measurements reveal the change in the surface free energy of wetting decreases linearly with plasma modification up to the monolayer point after which a constant limiting value of -24 mJ m-2 was attained. Films prepared at 20 W plasma power with a duty cycle of 10 μs:500 μs exhibit a high degree of hydroxyl (-OH) retention with minimal fragmentation of the monomer observed. Increasing the plasma power up to 125 W is found to improve -OH retention at the expense of ether formation generating films close to the monomer stoichiometry. Duty cycle plays an important role in controlling both film composition and thickness, with longer off times increasing -OH retention, while longer on times enhance allyl alcohol film growth

  6. Palladium Catalyzed Allylic C-H Alkylation

    DEFF Research Database (Denmark)

    Engelin, Casper Junker; Fristrup, Peter

    2011-01-01

    The atom-efficiency of one of the most widely used catalytic reactions for forging C-C bonds, the Tsuji-Trost reaction, is limited by the need of preoxidized reagents. This limitation can be overcome by utilization of the recently discovered palladium-catalyzed C-H activation, the allylic C...

  7. Pressure Dependent Product Formation in the Photochemically Initiated Allyl + Allyl Reaction

    Directory of Open Access Journals (Sweden)

    Thomas Zeuch

    2013-11-01

    Full Text Available Photochemically driven reactions involving unsaturated radicals produce a thick global layer of organic haze on Titan, Saturn’s largest moon. The allyl radical self-reaction is an example for this type of chemistry and was examined at room temperature from an experimental and kinetic modelling perspective. The experiments were performed in a static reactor with a volume of 5 L under wall free conditions. The allyl radicals were produced from laser flash photolysis of three different precursors allyl bromide (C3H5Br, allyl chloride (C3H5Cl, and 1,5-hexadiene (CH2CH(CH22CHCH2 at 193 nm. Stable products were identified by their characteristic vibrational modes and quantified using FTIR spectroscopy. In addition to the (re- combination pathway C3H5+C3H5 → C6H10 we found at low pressures around 1 mbar the highest final product yields for allene and propene for the precursor C3H5Br. A kinetic analysis indicates that the end product formation is influenced by specific reaction kinetics of photochemically activated allyl radicals. Above 10 mbar the (re- combination pathway becomes dominant. These findings exemplify the specificities of reaction kinetics involving chemically activated species, which for certain conditions cannot be simply deduced from combustion kinetics or atmospheric chemistry on Earth.

  8. Polystyrene-divinylbenzene-glycidyl methacrylate stationary phase grafted with poly (amidoamine) dendrimers for ion chromatography.

    Science.gov (United States)

    Guo, Dandan; Lou, Chaoyan; Zhang, Peimin; Zhang, Jiajie; Wang, Nani; Wu, Shuchao; Zhu, Yan

    2016-07-22

    In this work, a novel ion exchange stationary phase based on different generations of poly (amidoamine) dendrimers (PAMAM) was developed for the determination of inorganic anions and carbohydrates. Synthesis of the PAMAM was carried out with the polymerization reaction of ethylenediamine and methyl acrylate. The synthesized PAMAM was then grafted to the polystyrene-divinylbenzene-glycidyl methacrylate (PS-GMA) to form PAMAM-based beads. These beads were finally modified with 1,4-butanediol diglycidyl ether (BDDE) to generate the anion exchanger, which were characterized by scanning electron microscopy (SEM), brunauer-emmett-teller (BET), fourier transform infrared spectroscopy (FTIR), and elemental analysis. Elemental analysis, breakthrough curves and capacity factors showed that more epoxy groups and higher PAMAM generations in stationary phase could result in higher anion exchange capacity. The efficiency, durability and stability of the proposed anion exchanger were investigated by using six inorganic anions (fluoride, chloride, nitrite, bromide, nitrate and sulfate) and four carbohydrates (trehalose, glucose, maltotriose and galacturonic acid) as analytes, respectively. The reliability of the proposed ion chromatographic stationary phase was demonstrated by determining the content of galacturonic acid in polysaccharides from Poria cocos and Atractylodes macrocephala. The relative standard deviations of retention time, peak height, and peak area for galacturonic acid were 0.39%, 1.22%, and 2.02%, respectively. The spiked recoveries were in the range of 88.29%-100.51% for plant polysaccharides. Due to the good structural homogeneity, intense internal porosity, biological compatibility and high density of active groups in PAMAM, this grafted stationary phase showed good ion-exchange characteristics, especially in biological charged molecules. PMID:27311659

  9. Silicon-directed rhenium-catalyzed allylic carbaminations and oxidative fragmentations of γ-silyl allylic alcohols.

    Science.gov (United States)

    Chavhan, Sanjay W; Cook, Matthew J

    2014-04-22

    A highly regioselective allylic substitution of β-silyl allylic alcohols has been achieved that provides the branched isomer as a single product. This high level of regiocontrol is achieved through the use of a vinyl silane group that can perform a Hiyama coupling providing 1,3-disubstituted allylic amines. An unusual oxidative fragmentation product was also observed at elevated temperature that appears to proceed by a Fleming-Tamao-type oxidation-elimination pathway. PMID:24677380

  10. Temperature-controlled redox-neutral ruthenium(ii)-catalyzed regioselective allylation of benzamides with allylic acetates.

    Science.gov (United States)

    Manikandan, Rajendran; Jeganmohan, Masilamani

    2016-08-10

    Substituted aromatic amides reacted efficiently with allylic acetates in the presence of a cationic ruthenium complex in ClCH2CH2Cl at room temperature providing ortho allylated benzamides in a highly regioselective manner without any oxidant and base. The whole catalytic reaction occurred in a Ru(ii) oxidation state and thus the oxidation step is avoided. By tuning the reaction temperature, ortho allyl and vinyl benzamides were prepared exclusively. Later, ortho allyl and vinylated benzamides were converted into biologically useful six- and five-membered benzolactones in the presence of HCl. PMID:27456467

  11. Radiation-induced graft polymerization of glycidyl methacrylate onto nonwoven polypropylene

    International Nuclear Information System (INIS)

    The influence of the major grafting parameters (radiation dose, reaction time, and inhibitor concentration) on graft polymerization of glycidyl methacrylate from its 10% solution in methanol onto nonwoven polypropylene upon irradiation in a 1 MeV electron beam accelerator in air was studied. It is shown that the method of preliminary irradiation of the substrate affords glycidyl methacrylate grafting at 70 deg C most efficiently when Mohr's salt in amounts of 10-2 wt.% is added to the reaction mixture

  12. Toward Efficient Palladium-Catalyzed Allylic C-H Alkylation

    DEFF Research Database (Denmark)

    Jensen, Thomas; Fristrup, Peter

    2009-01-01

    Recent breakthroughs have proved that direct palladium (II)-catalyzed allylic C-H alkylation can be achieved. This new procedure shows that the inherent requirement for a leaving group in the Tsuji-Trost palladium-catalyzed allylic alkylation can be lifted. These initial reports hold great promise...

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

    Science.gov (United States)

    Minehan, Thomas G

    2016-06-21

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

  14. A recyclable heavy fluorous tag carrying an allyl alcohol pendant group: design and evaluation toward applications in synthetic carbohydrate chemistry.

    Science.gov (United States)

    Fukuda, Kazuo; Tojino, Mami; Goto, Kohtaro; Dohi, Hirofumi; Nishida, Yoshihiro; Mizuno, Mamoru

    2015-04-30

    Toward applications in synthetic carbohydrate chemistry, we converted our previous acid-resistant heavy fluorous tag [(Rf)3C-CH2-OH, 1] to allyl alcohol derivatives [(Rf)3C-CH2-O-(CH2)n-CH=CH-CH2-OH, 3 (n=1) or 4 (n=3)] by means of olefin cross metathesis. They were then subjected to β-glycosylation reactions by using a series of glycosyl donors, including glycosyl bromide and trichloroacetimidates. The terminal OH group in 3 and 4 was found to be β-glycosylated in moderate yield when 2,3,4,6-tetra-O-benzoyl-D-galactosyl trichloroacetimidate was used as the glycosyl donor. Upon a detachment reaction using Pd(PPh3)4, the initial heavy fluorous tag 1 was recovered in high yield (>90%) together with 1-hydroxy sugar, indicating that not only the allyl ether linkage in the glycosides but also the internal di-alkyl ether linkage in 4 be cleaved by the action of the Pd-catalyst enabling long-range olefin transmigration. Potential utility was demonstrated by using the tetra-O-benzoyl-β-D-galactosylated derivative of 3 in a series of deprotection, protection and glycosylation reactions, which were conductible in high yields without using chromatographic purification process. These findings prompt us to propose a general scheme in which the acid-resistant heavy fluorous compound 1 is applied as a recyclable tag in synthetic carbohydrate chemistry. PMID:25753904

  15. Glycidyl Azide Polymer-based Enhanced Energy LOVA Gun Propellant

    Directory of Open Access Journals (Sweden)

    R. R. Sanghavi

    2006-07-01

    Full Text Available In this study, cyclotrimethylene trinitramine propellants with triacetin (TA-plasticisedcellulose acetate (CA and nitrocellulose (NC combination as binders were evaluated for lowvulnerable ammunition (LOVA. Triacetin was replaced by energetic plasticiser; glycidyl azidepolymer (GAP in increments to enhance the performance in terms of force constant . In additionto ballistics, parameters like vulnerability, mechanical and thermal properties of GAP-basedpropellants in comparison to those of TA-based propellants, were also determined. The studybrings out that the incorporation of 2-6 per cent GAP in place of TA resulted in the enhancementof force constant by 22-70 J/g and improved overall combustion characteristics. DSC revealedthat thermal decomposition of GAP-LOVA propellants evolved more energy than TA-LOVApropellants. GAP-based LOVA propellant similar to TA-plasticised LOVA propellant, was foundsuperior to NQ propellant in vulnerability tests as well as in hot fragment conductive ignition(HFCI studies. As regards mechanical properties, incorporation of GAP resulted in improvedcompression strength.

  16. Macroporous poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) resins-Versatile immobilization supports for biocatalysts

    NARCIS (Netherlands)

    Miletic, Nemanja; Vukovic, Zorica; Nastasovic, Aleksandra; Loos, Katja; Miletić, Nemanja; Vuković, Zorica; Nastasović, Aleksandra

    2009-01-01

    Crosslinked macroporous hydrophilic poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate)s [abbreviated poly(GMA-co-EGDMA)] with identical chemical structure (60% of glycidyl methacrylate) but with varied average pore sizes (from 30 to 560 nm), specific surface areas (from 13.2 to 106.0 m(2)

  17. Chiral allyl silane additions to chiral α-substituted aldehydes

    International Nuclear Information System (INIS)

    Chiral allyl silane 3 reacted with chiral α-methyl-β-siloxy-aldehydes to afford the corresponding 1,4-syn-products with good diastereo-selectivities independent of the absolute stereochemistry of these aldehydes. The best selectivities are observed when the reactions are carried out by trans metallation of the allyl silane 3 using Tin (IV) Chloride in CH2 CL2 at -78 deg C, before addition of the aldehydes. (author)

  18. Zinc Mediated Tandem Fragmentation-Allylation of Methyl 5-Iodopentofuranosides

    DEFF Research Database (Denmark)

    Hyldtoft, Lene; Madsen, Robert

    1999-01-01

    In the presence of zinc and allyl bromide methyl 5-iodopentofuranosides undergo a tandem fragmentation alkylation to give functionalized dienes. These can undergo ring-closing olefin metathesis to produce cyclohexenes which on dihydroxylation give quercitols.......In the presence of zinc and allyl bromide methyl 5-iodopentofuranosides undergo a tandem fragmentation alkylation to give functionalized dienes. These can undergo ring-closing olefin metathesis to produce cyclohexenes which on dihydroxylation give quercitols....

  19. Gelation of photopolymerized hyaluronic acid grafted with glycidyl methacrylate

    Energy Technology Data Exchange (ETDEWEB)

    Prado, S.S.; Weaver, J.M.; Love, B.J., E-mail: bjlove@umich.edu

    2011-12-01

    Experiments have tracked the ambient gelation of a series of hydrophilic hyaluronic acid (HA) resins grafted with glycidyl methacrylate (GM) and photopolymerized as a function of dose. The resin mixtures range in GMHA concentration between 0.5 and 1.5% w/w in phosphate buffered saline (PBS). Illuminated at 20 mW/cm{sup 2}, the dynamic viscosity ({eta}(t)) has been tracked and characterized using the Boltzmann log-sigmoidal model. A gelled viscosity of {approx} 10 Pa s was determined at 0.5% w/w which rose to {approx} 50 Pa s at or above 1% w/w. More curing agent marginally increased the gel viscosity at each concentration. Time constants associated with viscosity advancement were shortest at [GMHA] = 1.0%; higher concentrations are attributed with lower quantum efficiency when illuminated. Subsequent frequency sweeps replicated already published work using similar GHMA concentrations in PBS. G' values ranged from 100 to 500 Pa over the formulation range with expected sensitivity to GMHA and curing agent concentration. Overall, the sigmoidal model represented this advancing viscosity data well, and further analysis of the physical significance of these model parameters may help in understanding photopolymerization of this complicated formulation more broadly. Highlights: {yields} The ambient dynamic viscosity of photopolymerized GMHA gels has been measured. {yields} 2 physical parameters and two time constants were extracted from the sigmoidal model. {yields} Higher crosslinker content for a fixed GMHA concentration led to higher gel viscosity. {yields} The time to toggle between the initial and final viscosity ranged between 5 and 10 s. {yields} Dynamic frequency sweep tests on cured gels also revealed G' values between 100 and 500 Pa.

  20. Gelation of photopolymerized hyaluronic acid grafted with glycidyl methacrylate

    International Nuclear Information System (INIS)

    Experiments have tracked the ambient gelation of a series of hydrophilic hyaluronic acid (HA) resins grafted with glycidyl methacrylate (GM) and photopolymerized as a function of dose. The resin mixtures range in GMHA concentration between 0.5 and 1.5% w/w in phosphate buffered saline (PBS). Illuminated at 20 mW/cm2, the dynamic viscosity (η(t)) has been tracked and characterized using the Boltzmann log-sigmoidal model. A gelled viscosity of ∼ 10 Pa s was determined at 0.5% w/w which rose to ∼ 50 Pa s at or above 1% w/w. More curing agent marginally increased the gel viscosity at each concentration. Time constants associated with viscosity advancement were shortest at [GMHA] = 1.0%; higher concentrations are attributed with lower quantum efficiency when illuminated. Subsequent frequency sweeps replicated already published work using similar GHMA concentrations in PBS. G' values ranged from 100 to 500 Pa over the formulation range with expected sensitivity to GMHA and curing agent concentration. Overall, the sigmoidal model represented this advancing viscosity data well, and further analysis of the physical significance of these model parameters may help in understanding photopolymerization of this complicated formulation more broadly. Highlights: → The ambient dynamic viscosity of photopolymerized GMHA gels has been measured. → 2 physical parameters and two time constants were extracted from the sigmoidal model. → Higher crosslinker content for a fixed GMHA concentration led to higher gel viscosity. → The time to toggle between the initial and final viscosity ranged between 5 and 10 s. → Dynamic frequency sweep tests on cured gels also revealed G' values between 100 and 500 Pa.

  1. Modification of polyethylene films by radiation grafting of glycidyl methacrylate and immobilization of β-cyclodextrin

    International Nuclear Information System (INIS)

    Glycidyl methacrylate was grafted onto polyethylene films using a preirradiation method with γ rays. The effect of absorbed dose, monomer concentration, and reaction time on the degree of grafting was determined. The grafted samples were verified by FTIR-ATR spectroscopy. β-Cyclodextrin was immobilized onto polypropylene modified with glycidyl methacrylate, and the ability of the cavities of β-cyclodextrin to form inclusion complexes was demonstrated using the typically organic compound approach with m-toluic acid (3-MBA) as a probe

  2. Thionine-modified poly(glycidyl methacrylate) nanospheres as labels of antibodies for biosensing applications

    Czech Academy of Sciences Publication Activity Database

    Zasońska, Beata Anna; Čadková, M.; Kovářová, A.; Bílková, Z.; Korecká, L.; Horák, Daniel

    2015-01-01

    Roč. 7, č. 44 (2015), s. 24926-24931. ISSN 1944-8244 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61389013 Keywords : glycidyl methacrylate * nanospheres * thionine Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 6.723, year: 2014

  3. Preparation and characterization of monodisperse silica-coated poly(glycidyl methacrylate) micropsheres

    Czech Academy of Sciences Publication Activity Database

    Grama, Silvia; Plichta, Zdeněk; Horák, Daniel

    Pisa : European Polymer Federation, 2013. P3-54. [European Polymer Congress - EPF 2013. 16.06.2013-21.06.2013, Pisa] R&D Projects: GA MŠk EE2.3.30.0029 Institutional support: RVO:61389013 Keywords : poly(glycidyl methacrylate) * microspheres * silica Subject RIV: CE - Biochemistry

  4. Gamma radiation-induced grafting of glycidyl methacrylate (GMA) onto water hyacinth fibers

    Science.gov (United States)

    Madrid, Jordan F.; Nuesca, Guillermo M.; Abad, Lucille V.

    2013-04-01

    Water hyacinth fibers (Eichhornia crassipes) were functionalized using radiation-induced graft polymerization of glycidyl methacrylate by γ-rays from 60Co source. The simultaneous grafting technique was employed wherein the water hyacinth fibers were irradiated in nitrogen atmosphere in the presence of glycidyl methacrylate dissolved in water/methanol solvent. The effects of different grafting parameters to the grafting yield were evaluated. The optimal values of solvent, absorbed dose, dose rate, and concentration of monomer were found to be 1:3 (volume/volume) water-methanol solvent, 10 kGy, 8 kGy h-1 dose rate and 5% volume/volume glycidyl methacrylate, respectively. Using the optimum conditions, degree of grafting of approximately 58% was achieved. The grafted water hyacinth fibers were characterized using Attenuated Total Reflectance-Fourier Transformed Infrared Spectroscopy (ATR-FTIR), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDX). The results of these tests confirmed the successful grafting of glycidyl methacrylate onto water hyacinth fibers.

  5. Monodisperse macroporous poly(glycidyl methacrylate) microspheres coated with silica: Design, preparation and characterization

    Czech Academy of Sciences Publication Activity Database

    Grama, Silvia; Plichta, Zdeněk; Trchová, Miroslava; Kovářová, Jana; Beneš, Milan J.; Horák, Daniel

    2014-01-01

    Roč. 77, April (2014), s. 11-17. ISSN 1381-5148 R&D Projects: GA MŠk EE2.3.30.0029 Institutional support: RVO:61389013 Keywords : multistep swelling polymerization * poly(glycidyl methacrylate) * poly(2,3-dihydroxypropyl methacrylate) Subject RIV: CE - Biochemistry Impact factor: 2.515, year: 2014

  6. Biocompatible monodisperse poly(glycidyl methacrylate) microspheres intended for biological applications

    Czech Academy of Sciences Publication Activity Database

    Grama, Silvia; Stoika, R.; Heuts, H.; Horák, Daniel

    Cancún : Zing Conferences, 2014. [Zing Polymer Chemistry Conference /4./. 10.12.2014-13.12.2014, Cancún] R&D Projects: GA MŠk(CZ) EE2.3.30.0029 Institutional support: RVO:61389013 Keywords : poly(glycidyl methacrylate) * microspheres * silica Subject RIV: CE - Biochemistry

  7. Actinic-radiation curable polymers prepared from a reactive polymer, halogenated cyclic anhydride and glycidyl ester

    International Nuclear Information System (INIS)

    A novel class of photosensitive polymers are disclosed which are prepared by the reaction, preferably in the presence of a catalyst, of a reactive polymer, a halogenated cyclic anhydride and glycidyl ester of an alpha, beta-unsaturated carboxylic acid. These polymers are capable of undergoing vinyl-type polymerization when exposed to actinic radiation

  8. Zwitterion-grafted monodisperse poly(glycidyl methacrylate) microspheres to minimize nonspecific protein adsorption

    Czech Academy of Sciences Publication Activity Database

    Horák, Daniel; Koubková, Jana; Proks, Vladimír; Trchová, Miroslava

    Riva del Garda : Elsevier, 2015. P1.006. [International Symposium Frontiers in Polymer Science /4./ - POLY 2015. 20.05.2015-22.05.2015, Riva del Garda] R&D Projects: GA MŠk(CZ) EE2.3.30.0029 Institutional support: RVO:61389013 Keywords : microspheres * poly(glycidyl methacrylate) * zwitterion Subject RIV: CE - Biochemistry

  9. Allyl-silica Hybrid Monoliths For Chromatographic Application

    Science.gov (United States)

    Guo, Wenjuan

    Column technology continues to be the most investigated topics in the separation world, since the column is the place where the chromatographic separation happens, making it the heart of the separation system. Allyl-silica hybrid monolithic material has been exploited as support material and potential stationary phases for liquid chromatography; the stationary phase anchored to the silica surface by Si-C bond, which is more pH stable than traditional stationary phase. First, nuclear magnetic resonance spectroscopy has been used to study the sol in the synthesis of allyl-silica hybrid monoliths. Allyl-trimethoxysilane (allyl-TrMOS), dimethyldimethoxysilane (DMDMOS) and tetramethoxysilane (TMOS) have been served as co-precursors in the sol-gel synthesis of organo-silica hybrid monolithic columns for liquid chromatography (LC). 29Si nuclear magnetic resonance (NMR) and 1H NMR spectroscopy were employed to monitor reaction profiles for the acid-catalyzed hydrolysis and initial condensation reactions of the individual precursor and the hybrid system. 29Si-NMR has also been used to identify different silane species formed during the reactions. The overall hydrolysis rate has been found to follow the trend DMDMOS > allyl-TrMOS > TMOS, if each precursor is reacted individually (homo-polymerization). Precursors show different hydrolysis rate when reacted together in the hybrid system than they are reacted individually. Cross-condensation products of TMOS and DMDMOS (QD) arise about 10 minutes of initiation of the reaction. The allyl-silica monolithic columns for capillary liquid chromatography can only be prepared in capillaries with 50 im internal diameter with acceptable performance. One of the most prominent problems related to the synthesis of silica monolithic structures is the volume shrinkage. The synthesis of allylfunctionalized silica hybrid monolithic structures has been studied in an attempt to reduce the volume shrinkage during aging, drying and heat treatment

  10. Ether formulations of relativity

    Energy Technology Data Exchange (ETDEWEB)

    Duffy, M.C.

    1980-12-01

    Contemporary ether theories are surveyed and criticized, especially those formally identical to orthodox Relativity. The historical development of Relativity, Special and General, in terms of an ether, is briefly indicated. Classical interpretations of Generalized Relativity using ether are compared to Euclidean formulations using a background space. The history of a sub-group of theories, formulating a 'new' Relativity involving modified transforms, is outlined. According to the theory with which they agree, recent supposed detections of drift are classified and criticized. Cosmological evidence suggesting an ether is mentioned. Only ether theories formally identical to Relativity have been published in depth. They stand criticized as being contrary to the positivist spirit. The history of mechanical analogues is traced, from Hartley's representing gravitating matter as spherical standing waves, to recent suggestions that vortex-sponge might model electromagnetic, quantum, uncertainty and faster-than-light phenomena. Contemporary theories are particular physical theories, themselves 'second interpretations' of a primary mathematical model. Mechanical analogues are auxiliary, not necessary, to other theory, disclosing relationships between classical and non-classical descriptions of assemblies charging state. The ether-relativity polemic, part of a broader dispute about relativity, is founded on mistaken conceptions of the roles of mathematical and physical models, mechanical analogues; and a distored view of history, which indicates that ether theories have become relativistic. 103 references.

  11. Ether formulations of relativity

    International Nuclear Information System (INIS)

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

  12. Scalable and sustainable electrochemical allylic C–H oxidation

    Science.gov (United States)

    Horn, Evan J.; Rosen, Brandon R.; Chen, Yong; Tang, Jiaze; Chen, Ke; Eastgate, Martin D.; Baran, Phil S.

    2016-05-01

    New methods and strategies for the direct functionalization of C–H bonds are beginning to reshape the field of retrosynthetic analysis, affecting the synthesis of natural products, medicines and materials. The oxidation of allylic systems has played a prominent role in this context as possibly the most widely applied C–H functionalization, owing to the utility of enones and allylic alcohols as versatile intermediates, and their prevalence in natural and unnatural materials. Allylic oxidations have featured in hundreds of syntheses, including some natural product syntheses regarded as “classics”. Despite many attempts to improve the efficiency and practicality of this transformation, the majority of conditions still use highly toxic reagents (based around toxic elements such as chromium or selenium) or expensive catalysts (such as palladium or rhodium). These requirements are problematic in industrial settings; currently, no scalable and sustainable solution to allylic oxidation exists. This oxidation strategy is therefore rarely used for large-scale synthetic applications, limiting the adoption of this retrosynthetic strategy by industrial scientists. Here we describe an electrochemical C–H oxidation strategy that exhibits broad substrate scope, operational simplicity and high chemoselectivity. It uses inexpensive and readily available materials, and represents a scalable allylic C–H oxidation (demonstrated on 100 grams), enabling the adoption of this C–H oxidation strategy in large-scale industrial settings without substantial environmental impact.

  13. Scalable and sustainable electrochemical allylic C-H oxidation.

    Science.gov (United States)

    Horn, Evan J; Rosen, Brandon R; Chen, Yong; Tang, Jiaze; Chen, Ke; Eastgate, Martin D; Baran, Phil S

    2016-05-01

    New methods and strategies for the direct functionalization of C-H bonds are beginning to reshape the field of retrosynthetic analysis, affecting the synthesis of natural products, medicines and materials. The oxidation of allylic systems has played a prominent role in this context as possibly the most widely applied C-H functionalization, owing to the utility of enones and allylic alcohols as versatile intermediates, and their prevalence in natural and unnatural materials. Allylic oxidations have featured in hundreds of syntheses, including some natural product syntheses regarded as "classics". Despite many attempts to improve the efficiency and practicality of this transformation, the majority of conditions still use highly toxic reagents (based around toxic elements such as chromium or selenium) or expensive catalysts (such as palladium or rhodium). These requirements are problematic in industrial settings; currently, no scalable and sustainable solution to allylic oxidation exists. This oxidation strategy is therefore rarely used for large-scale synthetic applications, limiting the adoption of this retrosynthetic strategy by industrial scientists. Here we describe an electrochemical C-H oxidation strategy that exhibits broad substrate scope, operational simplicity and high chemoselectivity. It uses inexpensive and readily available materials, and represents a scalable allylic C-H oxidation (demonstrated on 100 grams), enabling the adoption of this C-H oxidation strategy in large-scale industrial settings without substantial environmental impact. PMID:27096371

  14. Transition metal catalysed Grignard-like allylic activation across tetragonal tin(II) oxide

    Indian Academy of Sciences (India)

    Pradipta Sinha; Moloy Banerjee; Abhijit Kundu; Sujit Roy

    2002-08-01

    The reaction of allyl halide and a carbonyl compound under the aegis of tetragonal tin(II) oxide and catalytic 8, 10 metal complexes provides the corresponding homoallylic alcohol, via a novel allyl tin intermediate.

  15. Catalytic oxidation of dimethyl ether

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-05-10

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

  16. Direct activation of allylic alcohols in palladium catalyzed coupling reactions

    OpenAIRE

    Gümrükçü, Y.

    2014-01-01

    The direct use of allylic alcohols in substitution reactions without pre-activation of the hydroxyl-group into a better leaving group or the use of additional stoichiometric in situ activators remains challenging due to the poor leaving group ability of the hydroxyl-group. Hence, it is important to develop new methods to activate (bio-mass derived) allyl-alcohols, which allow ‘green’ chemical processes for a broad substrate range. This may have a considerable impact on the methodology for fin...

  17. Iridium-Catalyzed Selective Isomerization of Primary Allylic Alcohols.

    Science.gov (United States)

    Li, Houhua; Mazet, Clément

    2016-06-21

    This Account presents the development of the iridium-catalyzed isomerization of primary allylic alcohols in our laboratory over the past 8 years. Our initial interest was driven by the long-standing challenge associated with the development of a general catalyst even for the nonasymmetric version of this seemingly simple chemical transformation. The added value of the aldehyde products and the possibility to rapidly generate molecular complexity from readily accessible allylic alcohols upon a redox-economical isomerization reaction were additional sources of motivation. Certainly influenced by the success story of the related isomerization of allylic amines, most catalysts developed for the selective isomerization of allylic alcohols were focused on rhodium as a transition metal of choice. Our approach has been based on the commonly accepted precept that hydrogenation and isomerization are often competing processes, with the latter being usually suppressed in favor of the former. The cationic iridium complexes [(Cy3P)(pyridine)Ir(cod)]X developed by Crabtree (X = PF6) and Pfaltz (X = BArF) are usually considered as the most versatile catalysts for the hydrogenation of allylic alcohols. Using molecular hydrogen to generate controlled amounts of the active form of these complexes but performing the reaction in the absence of molecular hydrogen enabled deviation from the typical hydrogenation manifold and favored exclusively the isomerization of allylic alcohols into aldehydes. Isotopic labeling and crossover experiments revealed the intermolecular nature of the process. Systematic variation of the ligand on the iridium center allowed us to identify the structural features beneficial for catalytic activity. Subsequently, three generations of chiral catalysts have been investigated and enabled us to reach excellent levels of enantioselectivity for a wide range of 3,3-disubstituted aryl/alkyl and alkyl/alkyl primary allylic alcohols leading to β-chiral aldehydes. The

  18. Highly Enantioselective Formation of α-Allyl-α-Arylcyclopentanones via Pd-Catalysed Decarboxylative Asymmetric Allylic Alkylation.

    Science.gov (United States)

    Akula, Ramulu; Doran, Robert; Guiry, Patrick J

    2016-07-11

    A highly enantioselective Pd-catalysed decarboxylative asymmetric allylic alkylation of cyclopentanone derived α-aryl-β-keto esters employing the (R,R)-ANDEN-phenyl Trost ligand has been developed. The product (S)-α-allyl-α-arylcyclopentanones were obtained in excellent yields and enantioselectivities (up to >99.9 % ee). This represents one of the most highly enantioselective formations of an all-carbon quaternary stereogenic center reported to date. This reaction was demonstrated on a 4.0 mmol scale without any deterioration of enantioselectivity and was exploited as the key enantioselective transformation in an asymmetric formal synthesis of the natural product (+)-tanikolide. PMID:27191198

  19. Sulfonium-based Ionic Liquids Incorporating the Allyl Functionality

    Directory of Open Access Journals (Sweden)

    Paul J. Dyson

    2007-04-01

    Full Text Available A series of sulfonium halides bearing allyl groups have been prepared andcharacterized. Anion metathesis with Li[Tf2N] and Ag[N(CN2] resulted in sulfonium-basedionic liquids which exhibit low viscosities at room temperature. The solid state structure ofone of the halide salts was determined by single crystal X-ray diffraction.

  20. Magnetic poly(glycidyl methacrylate) microspheres for Campylobacter jejuni detection in food

    Czech Academy of Sciences Publication Activity Database

    Horák, Daniel; Hochel, I.

    061, - (2005), s. 1-12. ISSN 1618-7229 R&D Projects: GA ČR(CZ) GA525/05/0311; GA ČR(CZ) GA525/02/0287 Institutional research plan: CEZ:AV0Z40500505 Keywords : magnetic * microspheres * glycidyl methacrylate Subject RIV: GM - Food Processing Impact factor: 0.926, year: 2005 http://www.e-polymers.org

  1. Mechanically Strong Double Network Photocrosslinked Hydrogels from N, N-Dimethylacrylamide and Glycidyl Methacrylated Hyaluronan

    OpenAIRE

    Weng, Lihui; Gouldstone, Andrew; Wu, Yuhong; Chen, Weiliam

    2008-01-01

    Hyaluronan (HA) is a natural polysaccharide abundant in biological tissues and it can be modified to prepare biomaterials. In this work, HA modified with glycidyl methacrylate was photocrosslinked to form the first network (PHA), and then a series of highly porous PHA/N, N-dimethylacrylamide (DAAm) hydrogels (PHA/DAAm) with high mechanical strength were obtained by incorporating a second network of photocrosslinked DAAm into PHA network. Due to synergistic effect produced by double network (D...

  2. Ultrafine conducting fibers: metallization of poly(acrylonitrile-co-glycidyl methacrylate) nanofibers

    OpenAIRE

    Menceloğlu, Yusuf Z.; Menceloglu, Yusuf Z.; Demir, Mustafa Muammer; Uğur, Gökçe; Ugur, Gokce; Gülgün, Mehmet Ali; Gulgun, Mehmet Ali

    2005-01-01

    Electrospun poly(glycidylmethacrylate) (PGMA) and poly(acrylonitrile-co-glycidyl methacrylate) (P(AN-GMA)) nanofibers were coated with monodisperse silver nanoparticles by using an electroless plating technique at ambient conditions. Oxirane groups on the surface of nanofibers were replaced with reducing agent, hydrazine. Surface modified nanofibers were allowed to react with ammonia solution of AgNO3. A redox reaction takes place and metallic silver nucleate on fibers surface. Parameters aff...

  3. Characterization of collagen fiber grafted with glycidyl methacrylate monomer and treated with dibutyl amine

    International Nuclear Information System (INIS)

    Leather grafted with poly (glycidyl methacrylate) (L-g-PGMA) having graft yield of 26% and epoxy content 69.4 m mol/ 100 gm was prepared according to the emulsion polymerization technique and impregnated in different dibutyl amine solutions using amine/ epoxy molar ratio range from 0.5 up to 2.5. The obtained samples were characterized with respect to the nitrogen content, infrared spectroscopy, thermogravimetric analysis (TGA) analysis and the scanning electron microscope. The nitrogen content of the treated leather samples was increased by increasing the dibutyl amine concentration up to amine/ epoxy molar ratio of 2 after which it began to decrease. The water absorption, tensile strength and elongation (%) as well as hardness of the modified leather samples were studied and compared with the unmodified one. The colour strength values of dyed leather samples with acid dye were increased by grafting or by increasing the amine/epoxy molar ratio up to a value of 1.0 after which it begin to decrease. Meanwhile, the colour strength value of dyed leather sample with reactive dye was sharply decreased after grafting with poly (glycidyl methacrylate). On the other hand, pronounced increment in the colour strength value was obtained for the samples grafted with glycidyl methacrylate and treated with dibutyl acrylate amine and the colour strength is directly proportional to the sample nitrogen content

  4. The compound ethers of glycerin

    International Nuclear Information System (INIS)

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

  5. Rotational Spectroscopy of Isocyanic Molecules: Allyl Isocyanide and Diisocyanomethane

    Science.gov (United States)

    Motiyenko, R. A.; Margules, L.; Haykal, I.; Huet, T. R.; Cocinero, E. J.; Ecija, P.; Fernandez, J. A.; Castano, F.; Lesarri, A.; Guillemin, J.-C.

    2012-06-01

    Isocyanides are less stable isomers of nitriles and some of them have already been observed in the interstellar medium (HNC, CH_3NC, HCCNC). But still there exists a lack of experimental spectroscopic data on simple isocyanic molecules that can represent potential astrophysical interest. In this view we have performed high resolution studies of rotational spectra of allyl isocyanide (CH_2=CH--CH_2--NC) and diisocyanomethane (CN--CH_2--NC). The rotational spectra of allyl isocyanide have been measured in the frequency range 6 -- 18 GHz by means of FTMW spectrometer in Bilbao and in the frequency range 150 -- 945 GHz by means of classic absorption spectroscopy in Lille. Two stable confomers of allyl isocyanide have been observed in both series of measurements. In addition, all 13C-monosubstituted isotopologues and 15N isotopologues were detected in natural abundance. Due to much lower kinetic stability the rotational spectrum of diisocyanomethane has been measured only in absorption using the Lille spectrometer. The spectral assignments have been supported by high-level quantum chemical calculations. For both molecules accurate sets of rotational and centrifugal distortion constants (up to the octics) have been produced. As a result, reliable predictions of transitions frequencies suitable for astrophysical detection have been obtained for both molecules. Finally, the effective and substitution structures were determined for the two conformers of allyl isocyanide, comparing the result with ab initio data. This work is supported by Centre Nationale d'Etudes Spatiales (CNES), Action sur Projet Physico-Chimie du Milieu Interstellaire (PCMI-CNRS) and by the contract ANR-08-BLAN-0054. Spanish part acknowledges funding from the MICINN and the MINECO.

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

    Science.gov (United States)

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

    2016-01-20

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

  7. Enantioconvergent synthesis by sequential asymmetric Horner-Wadsworth-Emmons and palladium-catalyzed allylic substitution reactions

    DEFF Research Database (Denmark)

    Pedersen, Torben Møller; Hansen, E. Louise; Kane, John;

    2001-01-01

    A new method for enantioconvergent synthesis has been developed. The strategy relies on the combination of an asymmetric Horner-Wadsworth-Emmons (HWE) reaction and a palladium-catalyzed allylic substitution. Different $alpha@-oxygen-substituted, racemic aldehydes were initially transformed by...... asymmetric HWE reactions into mixtures of two major $alpha@,$beta@-unsaturated esters, possessing opposite configurations at their allylic stereocenters as well as opposite alkene geometry. Subsequently, these isomeric mixtures of alkenes could be subjected to palladium-catalyzed allylic substitution...

  8. Spectrum of Glycidyl Methacrylate—induced Mutation in Plasmid—Escherichia coli System

    Institute of Scientific and Technical Information of China (English)

    GAOHui-Lan; ZuoJin; 等

    1994-01-01

    In order to characterize the spectrum of mutation induced by glycidyl methacrylate(GMA),the plasmid pBR322 was modified with this mutagen in vitro.transfected into appropriate Escherichia coli host HB101.The mutants were then screned and defined by DNA sequencing.Sequence analysis reveals that GMA induces two classes of mutations:deletion of the mono-,di-or tetra-base or the insertion of mono-or di-base.Both types of muations,with about 10% frequency,occur predominantly at C.G runs and at 5'-CNCCN-3' sequence,which are hotspots for GMA damage and may cause frameshift muation.

  9. 40 CFR 721.10189 - Fatty acids, tall-oil, reaction products with (butoxymethyl) oxirane formaldehyde-phenol polymer...

    Science.gov (United States)

    2010-07-01

    ... products with (butoxymethyl) oxirane formaldehyde-phenol polymer glycidyl ether, morpholinepropanamine...-phenol polymer glycidyl ether, morpholinepropanamine, propylene glycol diamine and aliphatic polyamine, N... products with (butoxymethyl) oxirane formaldehyde-phenol polymer glycidyl ether,...

  10. Bacterial degradation of glycol ethers.

    Science.gov (United States)

    Kawai, F

    1995-12-01

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

  11. Proton conductive membranes based on poly (styrene-co-allyl alcohol semi-IPN

    Directory of Open Access Journals (Sweden)

    Felipe Augusto Moro Loureiro

    2014-01-01

    Full Text Available The optimization of fuel cell materials, particularly polymer membranes, for PEMFC has driven the development of methods and alternatives to achieve systems with more adequate properties to this application. The sulfonation of poly (styrene-co-allyl alcohol (PSAA, using sulfonating agent:styrene ratios of 2:1, 1:1, 1:2, 1:4, 1:6, 1:8 and 1:10, was previously performed to obtain proton conductive polymer membranes. Most of those membranes exhibited solubility in water with increasing temperature and showed conductivity of approximately 10-5 S cm-1. In order to optimize the PSAA properties, especially decreasing its solubility, semi-IPN (SIPN membranes are proposed in the present study. These membranes were obtained from the diglycidyl ether of bisphenol A (DGEBA, curing reactions in presence of DDS (4,4-diaminodiphenyl sulfone and PSAA. Different DGEBA/PSAA weight ratios were employed, varying the PSAA concentration between 9 and 50% and keeping the mass ratio of DGEBA:DDS as 1:1. The samples were characterized by FTIR and by electrochemical impedance spectroscopy. Unperturbed bands of PSAA were observed in the FTIR spectra of membranes, suggesting that chemical integrity of the polymer is maintained during the synthesis. In particular, bands involving C-C stretching (1450 cm-1, C=C (aromatic, ~ 3030 cm-1 and C-H (2818 and 2928 cm-1 were observed, unchanged after the synthesis. The disappearance or reduction of the intensity of the band at 916 cm-1, attributed to the DGEBA epoxy ring, is evidenced for all samples, indicating the epoxy ring opening and the DGEBA crosslinking. Conductivity of H3PO4 doped membranes increases with temperature, reaching 10-4 S cm-1.

  12. Immobilization of α-amylase onto poly(glycidyl methacrylate) grafted electrospun fibers by ATRP

    International Nuclear Information System (INIS)

    In this study, novel α-amylase immobilized poly(vinyl alcohol) (PVA) nanofibers were prepared. The PVA nanofiber surfaces were functionalized with 2-bromoisobutyryl bromide (BiBBr) and followed by surface initiated atom transfer radical polymerization (SI-ATRP) of glycidyl methacrylate (GMA). The morphology of the poly(glycidyl methacrylate) (PGMA) grafted PVA nanofibers was characterized by scanning electron microscopy (SEM). Also PGMA brushes were confirmed by X-ray photo electron microscopy (XPS). α-Amylase was immobilized in a one step process onto the PGMA grafted PVA nanofiber. The characteristic properties of the immobilized and free enzymes were examined. The thermal stability of the enzyme was improved and showed maximum activity at 37 °C by immobilization. pH values of the maximum activity of the free and immobilized enzymes were also found at 6.0 and 6.5, respectively. Free enzyme lost its activity completely within 15 days. The immobilized enzyme lost only 23.8% of its activity within 30 days. - Highlights: • Electrospun photocrosslinkable PVA nanofiber was prepared. • PGMA brushes were conducted on PVA nanofiber via SI-ATRP. • The immobilized enzyme showed maximum activity at pH 6.0 and at 37 °C. • Functionalized nanofibers may be used as promising supports for enzyme immobilization

  13. Versatility of Alkyne-Modified Poly(Glycidyl Methacrylate) Layers for Click Reactions

    International Nuclear Information System (INIS)

    Functional soft interfaces are of interest for a variety of technologies. We describe three methods for preparing substrates with alkyne groups, which show versatility for 'click' chemistry reactions. Two of the methods have the same root: formation of thin, covalently attached, reactive interfacial layers of poly(glycidyl methacrylate) (PGMA) via spin coating onto silicon wafers followed by reactive modification with either propargylamine or 5-hexynoic acid. The amine or the carboxylic acid moieties react with the epoxy groups of PGMA, creating interfacial polymer layers decorated with alkyne groups. The third method consists of using copolymers comprising glycidyl methacrylate and propargyl methacrylate (pGP). The pGP copolymers are spin coated and covalently attached on silicon wafers. For each method, we investigate the factors that control film thickness and content of alkyne groups using ellipsometry, and study the nanophase structure of the films using neutron reflectometry. Azide-terminated polymers of methacrylic acid and 2-vinyl-4,4-dimethylazlactone synthesized via reversible addition-fragmentation chain transfer polymerization were attached to the alkyne-modified substrates using 'click' chemistry, and grafting densities in the range of 0.007-0.95 chains nm-2 were attained. The maximum density of alkyne groups attained by functionalization of PGMA with propargylamine or 5-hexynoic acid was approximately 2 alkynes nm-3. The alkyne content obtained by the three decorating approaches was sufficiently high that it was not the limiting factor for the click reaction of azide-capped polymers.

  14. Immobilization of α-amylase onto poly(glycidyl methacrylate) grafted electrospun fibers by ATRP

    Energy Technology Data Exchange (ETDEWEB)

    Oktay, Burcu; Demir, Serap; Kayaman-Apohan, Nilhan, E-mail: napohan@marmara.edu.tr

    2015-05-01

    In this study, novel α-amylase immobilized poly(vinyl alcohol) (PVA) nanofibers were prepared. The PVA nanofiber surfaces were functionalized with 2-bromoisobutyryl bromide (BiBBr) and followed by surface initiated atom transfer radical polymerization (SI-ATRP) of glycidyl methacrylate (GMA). The morphology of the poly(glycidyl methacrylate) (PGMA) grafted PVA nanofibers was characterized by scanning electron microscopy (SEM). Also PGMA brushes were confirmed by X-ray photo electron microscopy (XPS). α-Amylase was immobilized in a one step process onto the PGMA grafted PVA nanofiber. The characteristic properties of the immobilized and free enzymes were examined. The thermal stability of the enzyme was improved and showed maximum activity at 37 °C by immobilization. pH values of the maximum activity of the free and immobilized enzymes were also found at 6.0 and 6.5, respectively. Free enzyme lost its activity completely within 15 days. The immobilized enzyme lost only 23.8% of its activity within 30 days. - Highlights: • Electrospun photocrosslinkable PVA nanofiber was prepared. • PGMA brushes were conducted on PVA nanofiber via SI-ATRP. • The immobilized enzyme showed maximum activity at pH 6.0 and at 37 °C. • Functionalized nanofibers may be used as promising supports for enzyme immobilization.

  15. Novel nitric oxide generating compound glycidyl nitrate enhances the therapeutic efficacy of chemotherapy and radiotherapy

    International Nuclear Information System (INIS)

    Highlights: • Glycidyl nitrate (GLYN) is a NO generating small molecule and has ability to release NO on bioactivation in tumor cells. • GLYN-induced intracellular NO generation was attenuated by NO scavengers. • GLYN increases tumor blood flow in tumor-bearing animal model. • GLYN significantly increased the anti-tumor efficacy of cisplatin and radiation therapy in mice. • GLYN is well tolerated with no obvious systemic toxicities at its effective therapeutic doses in preclinical animal studies. - Abstract: Selective release of nitric oxide (NO) in tumors could improve the tumor blood flow and drug delivery for chemotherapeutic agents and radiotherapy, thereby increasing the therapeutic index. Glycidyl nitrate (GLYN) is a NO generating small molecule, and has ability to release NO on bioactivation in SCC VII tumor cells. GLYN-induced intracellular NO generation was significantly attenuated by NO scavenger carboxy-PTIO (cPTIO) and NAC. GLYN significantly increases tumor blood flow, but has no effect on the blood flow of normal tissues in tumor-bearing mice. When used with cisplatin, GLYN significantly increased the tumor growth inhibition effect of cisplatin. GLYN also had a modest radiosensitizing effect in vitro and in vivo. GLYN was well tolerated and there were no acute toxicities found at its effective therapeutic doses in preclinical studies. These results suggest that GLYN is a promising new drug for use with chemotherapy and radiotherapy, and provide a compelling rationale for future studies of GLYN and related compounds

  16. Catalyst-controlled switch of regioselectivity in the asymmetric allylic alkylation of oxazolones with MBHCs.

    Science.gov (United States)

    Zhu, Gongming; Yang, Junxian; Bao, Guangjun; Zhang, Ming; Li, Jing; Li, Yiping; Sun, Wangsheng; Hong, Liang; Wang, Rui

    2016-06-14

    A catalyst-controlled switch of regioselectivity in asymmetric allylic alkylation of oxazolones with MBHCs was described. The SN2'-SN2' reaction catalysed by a quinine-derived base produced γ-selective secondary allylic oxazolone derivatives, whereas the addition-elimination reaction catalysed by an amino acid-derived bifunctional urea catalyst provided β-selective primary adducts. PMID:27250517

  17. Memory effects in palladium-catalyzed allylic Alkylations of 2-cyclohexen-1-yl acetate

    DEFF Research Database (Denmark)

    Svensen, Nina; Fristrup, Peter; Tanner, David Ackland;

    2007-01-01

    The objective of this work was to characterize the enantiospecificity of the allylic alkylation of enantioenriched 2-cyclohexen-1-yl acetate with the enolate ion of dimethyl malonate catalyzed by unsymmetrical palladium catalysts. The precatalysts employed were (eta(3)-allyl)PdLCl, where L is a...

  18. Palladium(0)-Catalyzed Intermolecular Allylic Dearomatization of Indoles by a Formal [4+2] Cycloaddition Reaction.

    Science.gov (United States)

    Gao, Run-Duo; Xu, Qing-Long; Zhang, Bo; Gu, Yiting; Dai, Li-Xin; You, Shu-Li

    2016-08-01

    Bridged indoline derivatives were synthesized by an intermolecular Pd-catalyzed allylic dearomatization reaction of substituted indoles. The reaction between indoles and allyl carbonates bearing a nucleophilic alcohol side-chain proceeds in a cascade fashion, providing bridged indolines in excellent enantioselectivity. PMID:27321285

  19. Trifluoromethylallylation of Heterocyclic C-H Bonds with Allylic Carbonates under Rhodium Catalysis.

    Science.gov (United States)

    Choi, Miji; Park, Jihye; Sharma, Satyasheel; Jo, Hyeim; Han, Sangil; Jeon, Mijin; Mishra, Neeraj Kumar; Han, Sang Hoon; Lee, Jong Suk; Kim, In Su

    2016-06-01

    The rhodium(III)-catalyzed γ-trifluoromethylallylation of various heterocyclic C-H bonds with CF3-substituted allylic carbonates is described. These reactions provide direct access to linear CF3-containing allyl frameworks with complete trans-selectivity via C-H bond activation followed by a formal SN-type reaction pathway. PMID:27187625

  20. Z-Selective copper-catalyzed asymmetric allylic alkylation with Grignard reagents.

    Science.gov (United States)

    Giannerini, Massimo; Fañanás-Mastral, Martín; Feringa, Ben L

    2012-03-01

    Allylic gem-dichlorides undergo regio- and enanantioselective (er up to 99:1) copper-catalyzed allylic alkylation with Grignard reagents affording chiral Z-vinyl chlorides. This highly versatile class of synthons can be subjected to Suzuki cross coupling affording optically active Z-alkenes and 1,3-cis,trans dienes. PMID:22352853

  1. Z-Selective Copper-Catalyzed Asymmetric Allylic Alkylation with Grignard Reagents

    OpenAIRE

    Giannerini, Massimo; Fananas-Mastral, Martin; Feringa, Ben L.; Fañanás-Mastral, Martín

    2012-01-01

    Allylic gem-dichlorides undergo regio- and enanantioselective (er up to 99:1) copper-catalyzed allylic alkylation with Grignard reagents affording chiral Z-vinyl chlorides. This highly versatile class of synthons can be subjected to Suzuki cross coupling affording optically active Z-alkenes and 1,3-cis,trans dienes.

  2. Ether and Relativity

    CERN Document Server

    Farhoudi, Mehrdad

    2015-01-01

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

  3. Ether and Relativity

    Science.gov (United States)

    Farhoudi, Mehrdad; Yousefian, Maysam

    2016-05-01

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

  4. Green Synthesis and Regioselective Control of Sn/I2 Mediated Allylation of Carbonyl Compounds with Crotyl Halide in Water

    Institute of Scientific and Technical Information of China (English)

    ZHANG,Yan; ZHA,Zhang-Gen; ZHOU,Yu-Qing; WANG,Zhi-Yong

    2004-01-01

    @@ Barbier-type carbonyl allylation is particularly useful due to ease of operation and the availability and tractability of allylic substrates,[1] Metals such as indium, zinc and tin are often used as the mediator. Here we present a green approach toward the synthesis, that is, Sn/I2 mediated allylation of carbonyl compounds with crotyl halide in water.

  5. Mitigated reactive oxygen species generation leads to an improvement of cell proliferation on poly[glycidyl methacrylate-co-poly(ethylene glycol) methacrylate] functionalized polydimethylsiloxane surfaces.

    Science.gov (United States)

    Yu, Ling; Shi, ZhuanZhuan; Gao, LiXia; Li, ChangMing

    2015-09-01

    In vitro cell-based analysis is strongly affected by material's surface chemical properties. The cell spreading, migration, and proliferation on a substrate surface are initiated and controlled by successful adhesion, particularly for anchor-dependent cells. Unfortunately, polydimethylsiloxane (PDMS), one of the most used polymeric materials for construction of microfluidic and miniaturized biomedical analytic devices, is not a cell-friendly surface because of its inherent hydrophobic property. Herein, a poly[glycidyl methacrylate-co-poly(ethylene glycol) methacrylate] (poly(GMA-co-pEGMA)) polymer brush was synthesized on a PDMS surface through a surface-initiated atom-transfer radical polymerization method. Contact angle and Fourier transform infrared characterization show that the poly (GMA-co-pEGMA) polymer brush functionalization can increase wettability of PDMS and introduce epoxy, hydroxyl, and ether groups into PDMS surface. In vitro cell growth assay demonstrates that cell adhesion and proliferation on poly(GMA-co-pEGMA) polymer brush-functionalized PDMS (poly(GMA-co-pEGMA)@PDMS) are better than on pristine PDMS. Additionally, immobilization of collagen type I (CI) and fibronectin (FN) on poly(GMA-co-pEGMA)@PDMS is better than direct coating of CI and FN on pristine PDMS to promote cell adhesion. Furthermore, increased intracellular reactive oxygen species and cell mitochondrial membrane depolarization, two indicators of cell oxidative stress, are observed from cells growing on pristine PDMS, but not from those on poly(GMA-co-pEGMA)@PDMS. Collectively, we demonstrate that poly(GMA-co-pEGMA) functionalization can enhance cell adhesion and proliferation on PDMS, and thus can be potentially used for microfluidic cell assay devices for cellular physiology study or drug screening. PMID:25711883

  6. Construction of an Asymmetric Quaternary Carbon Center via Allylation of Hydrazones

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Bum; Satyender, Apuri; Jang, Doo Ok [Yonsei Univ., Wonju (Korea, Republic of)

    2013-11-15

    Asymmetric indium-mediated allylation of imine derivatives bearing a chiral auxiliary is a reliable strategy for the synthesis of chiral homoallylic amines. Various techniques for indium-mediated stereoselective allylation of imines bearing a chiral auxiliary have been reported. In 1997 Loh and co-workers reported indium-mediated allylation with imines derived from L-valine methyl ester. Since then, many forms of indium-mediated allylation bearing a chiral auxiliary have been reported, including imines derived from (S)-valinol, (R)-phenylglycinol, uracil, (R)-phenylglycinol methyl ester, N-tert-butanesufinamide, and (1R,2S)-1-amino-2-indanol. However, the synthesis of chiral auxiliaries often involves a laborious multi-step synthesis with expensive reagents. Therefore, the development of readily accessible chiral auxiliaries for asymmetric indium-mediated all-ylation is in high demand.

  7. Direct analysis of intact glycidyl fatty acid esters in edible oils using gas chromatography-mass spectrometry

    NARCIS (Netherlands)

    H. van Steenbergen; K. Hrnčiřík; A. Ermacora; S. de Koning; H.-G. Janssen

    2013-01-01

    Glycidyl esters (GE), fatty acid esters of glycidol, are process contaminants formed during edible oil processing. A novel direct method for the determination of intact GE in oils and fats based on gas chromatography-mass spectrometry (GC-MS) is presented. The method consists of a simple extraction

  8. Preparation of magnetic poly(glycidyl methacrylate) microspheres by emulsion polymerization in the presence of sterically stabilized iron oxide nanoparticles

    Czech Academy of Sciences Publication Activity Database

    Horák, Daniel; Chekina, N.

    2006-01-01

    Roč. 102, č. 5 (2006), s. 4348-4357. ISSN 0021-8995 R&D Projects: GA ČR GA203/05/2256 Institutional research plan: CEZ:AV0Z40500505 Keywords : iron oxide * emulsion polymerization * glycidyl methacrylate Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.306, year: 2006

  9. Electrorheology of silicone oil suspensions of urea-modified poly[(glycidyl methacrylate)-co-(ethylene dimethacrylate)] particles

    Czech Academy of Sciences Publication Activity Database

    Belza, T.; Pavlínek, V.; Sáha, P.; Beneš, Milan J.; Horák, Daniel; Quadrat, Otakar

    2007-01-01

    Roč. 385, č. 1 (2007), s. 1-8. ISSN 0378-4371 R&D Projects: GA MŠk 2B06053 Institutional research plan: CEZ:AV0Z40500505 Keywords : Electrorheology * Suspension * Poly(glycidyl methacrylate-co-(ethylene dimethacrylate) Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.430, year: 2007

  10. Synthesis, Molecular Structure and Characterization of Allylic Derivatives of 6-Amino-3-methyl-1,2,4-triazolo[3,4-f][1,2,4]-triazin-8(7H-one

    Directory of Open Access Journals (Sweden)

    Gene-Hsiang Lee

    2006-06-01

    Full Text Available 1-Allyl- (2 and 7-allyl-6-amino-3-methyl-1,2,4-triazolo[3,4-f][1,2,4]triazin-8(7H-one (3 were obtained via the 18-crown-6-ether catalyzed room temperature reactionof 6-amino-3-methyl-1,2,4-triazolo[3,4-f][1,2,4]triazin-8(7H-one (1 with potassiumcarbonate and allyl bromide in dry acetone. The structures of these two derivatives wereverified by 2D-NMR measurements, including gHSQC and gHMBC measurements. Theminor compound 2 may possess aromatic character. A single crystal X-ray diffractionexperiment indicated that the major compound 3 crystallizes from dimethyl sulfoxide in themonoclinic space group P21/n and its molecular structure includes an attached dimethylsulfoxide molecule, resulting in the molecular formula C10H16N6O2S. Molecular structuresof 3 are linked by extensive intermolecular N-H···N hydrogen bonding [graph set C 1 (7]. 1Each molecule is attached to the dimethyl sulfoxide oxygen via N-H···O intermolecularhydrogen bonding. The structure is further stabilized by π-π stacking interactions.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  12. Direct Dimethyl Ether Synthesis

    Institute of Scientific and Technical Information of China (English)

    Takashi Ogawa; Norio Inoue; Tutomu Shikada; Yotaro Ohno

    2003-01-01

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

  13. On the formation of porous structure during the synthesis of macroporous copolymers based on glycidyl methacrylate

    Directory of Open Access Journals (Sweden)

    Jovanović Slobodan M.

    2004-01-01

    Full Text Available The results obtained during the investigation of the influence of the inert component composition and the type of copolymerization reaction on the porosity parameters of the macroporous copolymer of glycidyl methacrylate (GMA and ethylene glycol dimethacrylate (EGMA [abbreviated poly(GMA-co-EG-DMA] are presented. A mixture of cyclohexanol and aliphatic alcohol or non-ionic surfactants with hydrophilic-lipophilic balance values (HLB of 5 or 9 was used as the inert component. The copolymerization was performed in suspension and in a cast. It was shown that poly(GMA-co-EGDMA samples with enhanced porosity were obtained in the case of copolymerization in a cast, compared with samples obtained by suspension copolymerization. Also, it was concluded that the inert component solubility parameter cannot be used as the only criterium which determines the formation of the macro porous structure in poly(GMA-co-EGDMA.

  14. The effect of frying on glycidyl esters content in palm oil.

    Science.gov (United States)

    Aniołowska, Magda; Kita, Agnieszka

    2016-07-15

    The changes in palm oil, as affected by frying temperature, and content of the glycidyl esters (GEs) were studied. Potato chips were fried intermittently in palm oil, which was heated for 8 h daily over five consecutive days. Frying was conducted at three frying temperatures: 150, 165 and 180 °C. Thermo-oxidative alterations of the oil were measured by acid and anisidine values, changes in fatty acid composition, total polar components, polar fraction composition and colour components formation. Content of GE was measured by liquid chromatography-mass spectrometry. Results showed that amount of products of hydrolysis, oxidation and polymerization (excluding decrease of degree of unsaturation) increased significantly as a function of frying temperature and time. Between GEs of fatty acids the most abundant were esters of palmitic and oleic acids. With increasing temperature and frying time, the content of GE decreased. The extent of GE decrease was correlated with degree of oil degradation. PMID:26948594

  15. Thin-film type Li-ion battery, using a polyethylene separator grafted with glycidyl methacrylate

    International Nuclear Information System (INIS)

    For the improvement of organic electrolyte holding ability, the hydrophobic surface of a porous polyethylene (PE)-membrane separator was modified by grafting a hydrophilic monomer, glycidyl methacrylate (GMA), PE-g-GMA, by using electron beam technology, and applied to a thin film type Li-ion battery to elucidate the effect of a surface modification of a PE membrane separator on the cyclic life of Li-ion batteries. The Li-ion battery using the PE-g-GMA membrane separator showed a better cycle life than that of the unmodified PE membrane separator, indicating that the surface hydrophilicity of the PE membrane separator improved the electrolyte holding capability between the electrodes in the Li-ion cell and prevented the electrolyte leakage

  16. RAFT Copolymerization of Glycidyl Methacrylate and N,N-Dimethylaminoethyl Methacrylate

    Institute of Scientific and Technical Information of China (English)

    曹俊; 张丽芬; 潘向强; 程振平; 朱秀林

    2012-01-01

    In this work, copolymerization of two functional monomers, glycidyl methacrylate (GMA) and N,N-dimethylaminoethyl methacrylate (DMAEMA), was firstly carried out via reversible addition-fragmentation chain transfer (RAFT) polymerization successfully. The copolymerization kinetics was investigated under the molar ratio of n[GMA+DMAEMA]o/n[AIBN]o/n[CPDN]o=300/1/3 at 60℃. The copolymerization showed typical "living" features such as first-order polymerization kinetics, linear increase of molecular weight with monomer conversion and narrow molecular weight distribution. The reactivity ratios of GMA and DMAEMA were calculated by the extended Kelen-Tudos linearization methods. The epoxy group of the copolymer PGMA-co-PDMAEMA remained intact under the conditions of RAFT copolymerization and could easily be post-modified by ethylenedia- mine. Moreover, the modified copolymer could be used as a gene carrier.

  17. Crystallization kinetics and nucleation parameters of Nylon 6 and poly(ethylene-co-glycidyl methacrylate) blend

    International Nuclear Information System (INIS)

    Blend of Nylon 6 and poly(ethylene-co-glycidyl methacrylate) (PEGMA) were prepared by a twin-screw extruder. Morphology observed with scanning electron microscopies (SEM) show PEGMA is well dispersed in Nylon 6 matrix. Isothermal and nonisothermal crystallization of the blend was investigated by differential scanning calorimeter (DSC) and crystallization kinetics was described by Avrami and Tobin models. Equilibrium melting temperatures were estimated from linear Hoffman-Weeks relationship. All analyses showed that the reaction between PEGMA and Nylon 6 reduced the molecular mobility and reduced the crystallization rate. Expand Kg and U* in the Hoffman-Lauritzen equation by Vyazovkin's method demonstrated that Nylon 6/PEGMA had higher Kg and U* values and provided another supportive evidence to the above interpretation

  18. Crystallization kinetics and nucleation parameters of Nylon 6 and poly(ethylene-co-glycidyl methacrylate) blend

    Energy Technology Data Exchange (ETDEWEB)

    Huang, J.-W. [Department of Styling and Cosmetology, Tainan University of Technology, 529 Chung Cheng Road, Yung Kang City 710, Taiwan (China)], E-mail: jw.huang@msa.hinet.net; Chang, C.-C. [Department of International Business Management, Tainan University of Technology, 529 Chung Cheng Road, Yung Kang City 710, Taiwan (China); Kang, C.-C. [R and D Center, Hi-End Polymer Film Co., Ltd., 15-1 Sin Jhong Road, Sin Ying City 730, Taiwan (China); Yeh, M.-Y. [Department of Chemistry, National Cheng Kung University, No. 1, University Road, Tainan City 701, Taiwan (China); Sustainable Environment Research Centre, National Cheng Kung University, Taiwan (China)

    2008-02-05

    Blend of Nylon 6 and poly(ethylene-co-glycidyl methacrylate) (PEGMA) were prepared by a twin-screw extruder. Morphology observed with scanning electron microscopies (SEM) show PEGMA is well dispersed in Nylon 6 matrix. Isothermal and nonisothermal crystallization of the blend was investigated by differential scanning calorimeter (DSC) and crystallization kinetics was described by Avrami and Tobin models. Equilibrium melting temperatures were estimated from linear Hoffman-Weeks relationship. All analyses showed that the reaction between PEGMA and Nylon 6 reduced the molecular mobility and reduced the crystallization rate. Expand K{sub g} and U* in the Hoffman-Lauritzen equation by Vyazovkin's method demonstrated that Nylon 6/PEGMA had higher K{sub g} and U* values and provided another supportive evidence to the above interpretation.

  19. Application of magnetic poly(styrene-glycidyl methacrylate) microspheres for immunomagnetic separation of bone marrow cells

    Energy Technology Data Exchange (ETDEWEB)

    Chung, T.-H.; Chang, J.-Y. [Department of Chemical Engineering, National Chung Cheng University, Chiayi 621, Taiwan (China); Lee, W.-C. [Department of Chemical Engineering, National Chung Cheng University, Chiayi 621, Taiwan (China)], E-mail: chmwcl@ccu.edu.tw

    2009-05-15

    Surface-functionalized magnetic poly(styrene-glycidyl methacrylate) (PS-GMA) microspheres were prepared and coupled with Sca-1 antibody for cell selection from murine bone marrow mononuclear cells (MNCs). Biotinylated Sca-1 antibody could be directly coupled to avidin-bound magnetic microspheres. Alternatively, oxidized goat anti-mouse antibody was covalently bound onto the amino group-containing magnetic microspheres in a site-directed manner, and the resultant conjugate was coupled with non-modified Sca-1 antibody. Using the indirect antibody-bound magnetic microspheres, the purity of isolated Sca-1{sup +} cells increased with bead-to-cell ratio. Using a bead-to-cell ratio of 10 beads/cell, a purity of 85% Sca-1{sup +} cells corresponding to a 17-fold enrichment was achieved.

  20. Application of magnetic poly(styrene-glycidyl methacrylate) microspheres for immunomagnetic separation of bone marrow cells

    International Nuclear Information System (INIS)

    Surface-functionalized magnetic poly(styrene-glycidyl methacrylate) (PS-GMA) microspheres were prepared and coupled with Sca-1 antibody for cell selection from murine bone marrow mononuclear cells (MNCs). Biotinylated Sca-1 antibody could be directly coupled to avidin-bound magnetic microspheres. Alternatively, oxidized goat anti-mouse antibody was covalently bound onto the amino group-containing magnetic microspheres in a site-directed manner, and the resultant conjugate was coupled with non-modified Sca-1 antibody. Using the indirect antibody-bound magnetic microspheres, the purity of isolated Sca-1+ cells increased with bead-to-cell ratio. Using a bead-to-cell ratio of 10 beads/cell, a purity of 85% Sca-1+ cells corresponding to a 17-fold enrichment was achieved.

  1. Application of magnetic poly(styrene-glycidyl methacrylate) microspheres for immunomagnetic separation of bone marrow cells

    Science.gov (United States)

    Chung, Ting-Hao; Chang, Jing-Yi; Lee, Wen-Chien

    2009-05-01

    Surface-functionalized magnetic poly(styrene-glycidyl methacrylate) (PS-GMA) microspheres were prepared and coupled with Sca-1 antibody for cell selection from murine bone marrow mononuclear cells (MNCs). Biotinylated Sca-1 antibody could be directly coupled to avidin-bound magnetic microspheres. Alternatively, oxidized goat anti-mouse antibody was covalently bound onto the amino group-containing magnetic microspheres in a site-directed manner, and the resultant conjugate was coupled with non-modified Sca-1 antibody. Using the indirect antibody-bound magnetic microspheres, the purity of isolated Sca-1 + cells increased with bead-to-cell ratio. Using a bead-to-cell ratio of 10 beads/cell, a purity of 85% Sca-1 + cells corresponding to a 17-fold enrichment was achieved.

  2. Versatility of Alkyne-Modified Poly(Glycidyl Methacrylate) Layers for Click Reactions

    Energy Technology Data Exchange (ETDEWEB)

    Soto-Cantu, Dr. Erick [University of Tennessee, Knoxville (UTK); Lokitz, Bradley S [ORNL; Hinestrosa Salazar, Juan Pablo [Clemson University; Deodhar, Chaitra [University of Tennessee, Knoxville (UTK); Messman, Jamie M [ORNL; Ankner, John Francis [ORNL; Kilbey, II, S Michael [ORNL

    2011-01-01

    Functional soft interfaces are of interest for a variety of technologies. We describe three methods for preparing substrates with alkyne groups, which show versatility for 'click' chemistry reactions. Two of the methods have the same root: formation of thin, covalently attached, reactive interfacial layers of poly(glycidyl methacrylate) (PGMA) via spin coating onto silicon wafers followed by reactive modification with either propargylamine or 5-hexynoic acid. The amine or the carboxylic acid moieties react with the epoxy groups of PGMA, creating interfacial polymer layers decorated with alkyne groups. The third method consists of using copolymers comprising glycidyl methacrylate and propargyl methacrylate (pGP). The pGP copolymers are spin coated and covalently attached on silicon wafers. For each method, we investigate the factors that control film thickness and content of alkyne groups using ellipsometry, and study the nanophase structure of the films using neutron reflectometry. Azide-terminated polymers of methacrylic acid and 2-vinyl-4,4-dimethylazlactone synthesized via reversible addition-fragmentation chain transfer polymerization were attached to the alkyne-modified substrates using 'click' chemistry, and grafting densities in the range of 0.007-0.95 chains nm{sup -2} were attained. The maximum density of alkyne groups attained by functionalization of PGMA with propargylamine or 5-hexynoic acid was approximately 2 alkynes nm{sup -3}. The alkyne content obtained by the three decorating approaches was sufficiently high that it was not the limiting factor for the click reaction of azide-capped polymers.

  3. Organic monolith frits encased in polyether ether ketone tubing with improved durability for liquid chromatography.

    Science.gov (United States)

    Park, Sin Young; Cheong, Won Jo

    2015-09-01

    This study introduces a preparation method for polymer-encased monolith frits with improved durability for liquid chromatography columns. The inner surface of the polyether ether ketone tubing is pretreated with sulfuric acid in the presence of catalysts (vanadium oxide and sodium sulfate). The tubing was rinsed with water and acetone, flushed with nitrogen, and treated with glycidyl methacrylate. After washing, the monolith reaction mixture composed of lauryl methacrylate, ethylene glycol dimethacrylate, initiator, and porogenic solvent was filled in the tubing and subjected to in situ polymerization. The tubing was cut into thin slices and used as frits for microcolumns. To check their durability, the frit slices were placed in a vial and a heavy impact was applied on the vial by a vortex mixer for various periods. The frits made in the presence of catalysts were found to be more durable than those made without catalysts. Furthermore, when the monolith-incorporated tubing was used as a chromatography column, the column prepared in the presence of catalysts resulted in a better separation efficiency. The separation performance of the columns installed with the polyether ether ketone encased monolith frits was comparable to that of the columns installed with the commercial stainless-steel screen frits. PMID:26097071

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

    Directory of Open Access Journals (Sweden)

    Lin Jiang

    2015-05-01

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

  5. Rearrangements of Cycloalkenyl Aryl Ethers

    Directory of Open Access Journals (Sweden)

    Mercedesz Törincsi

    2016-04-01

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

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

    Institute of Scientific and Technical Information of China (English)

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

    2000-01-01

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

  7. Grafting emulsion polymerization of glycidyl methacrylate onto leather by chemical and gamma ray as different initiation systems

    International Nuclear Information System (INIS)

    The grafting emulsion polymerization of glycidyl methacrylate onto leather was carried out by chemical and gamma ray as two different initiation systems. The rate of grafting of glycidyl methacrylate onto leather was found to be dependent on the chemical initiation systems: ammonium persulphate/acetone sodium bisulphite (AmPS/ASBS), potassium persulphate/acetone sodium bisulphite (KPS/ASBS) and sodium persulphate/acetone sodium bisulphite (SPS/ASBS) to the powers 1.06, 0,48 and 0.43 respectively and to the powers 0.63, 0.46 and 0.43 with respect to the emulsifier sodium dodecyl sulphate SDS while the powers were found to be 1.41 , 0.70 and 0.81 with respect to monomer concentration respectively. The grafted leather was characterized via FTIR. The evaluation of the grafted leather through water absorption, tensile strength and hardness measurements has been discussed

  8. Polymer electrolyte based on crosslinked poly(glycidyl methacrylate) and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide

    Science.gov (United States)

    Fei, Beatrice Wong Chui; Hanifah, Sharina Abu; Ahmad, Azizan; Hassan, Nur Hasyareeda

    2015-09-01

    Polymer electrolytes based on crosslinked poly(glycidyl methacrylate) as polymer host and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BmimTFSI) as incorporated salt were prepared by in-situ photopolymerization technique. The complexes with different mass ratio of glycidyl methacrylate (GMA) monomer to BmimTFSI were investigated. The ionic conductivity of the polymer electrolyte was increased and reach the highest value of 7.50 × 10-4 S cm-1 at the ratio of 3:7 (GMA: BmimTFSI). The interaction between the polymer host and ionic liquid was proved by Attenuated Total Reflectance-Fourier Transformation Infra-Red Spectroscopy (ATR-FTIR). Meanwhile, the X-ray diffraction analysis shows the amorphousity of the polymer electrolyte film increase with the ionic liquid ratio.

  9. Polymer electrolyte based on crosslinked poly(glycidyl methacrylate) and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide

    International Nuclear Information System (INIS)

    Polymer electrolytes based on crosslinked poly(glycidyl methacrylate) as polymer host and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BmimTFSI) as incorporated salt were prepared by in-situ photopolymerization technique. The complexes with different mass ratio of glycidyl methacrylate (GMA) monomer to BmimTFSI were investigated. The ionic conductivity of the polymer electrolyte was increased and reach the highest value of 7.50 × 10−4 S cm−1 at the ratio of 3:7 (GMA: BmimTFSI). The interaction between the polymer host and ionic liquid was proved by Attenuated Total Reflectance-Fourier Transformation Infra-Red Spectroscopy (ATR-FTIR). Meanwhile, the X-ray diffraction analysis shows the amorphousity of the polymer electrolyte film increase with the ionic liquid ratio

  10. Polymer electrolyte based on crosslinked poly(glycidyl methacrylate) and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide

    Energy Technology Data Exchange (ETDEWEB)

    Fei, Beatrice Wong Chui; Hanifah, Sharina Abu; Ahmad, Azizan; Hassan, Nur Hasyareeda [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43000 Bangi, Selangor Darul Ehsan (Malaysia)

    2015-09-25

    Polymer electrolytes based on crosslinked poly(glycidyl methacrylate) as polymer host and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BmimTFSI) as incorporated salt were prepared by in-situ photopolymerization technique. The complexes with different mass ratio of glycidyl methacrylate (GMA) monomer to BmimTFSI were investigated. The ionic conductivity of the polymer electrolyte was increased and reach the highest value of 7.50 × 10{sup −4} S cm{sup −1} at the ratio of 3:7 (GMA: BmimTFSI). The interaction between the polymer host and ionic liquid was proved by Attenuated Total Reflectance-Fourier Transformation Infra-Red Spectroscopy (ATR-FTIR). Meanwhile, the X-ray diffraction analysis shows the amorphousity of the polymer electrolyte film increase with the ionic liquid ratio.

  11. Asymmetric Catalysis with CO2 : The Direct α-Allylation of Ketones.

    Science.gov (United States)

    Pupo, Gabriele; Properzi, Roberta; List, Benjamin

    2016-05-10

    Quaternary stereocenters are found in numerous bioactive molecules. The Tsuji-Trost reaction has proven to be a powerful C-C bond forming process, and, at least in principle, should be well suited to access quaternary stereocenters via the α-allylation of ketones. However, while indirect approaches are known, the direct, catalytic asymmetric α-allylation of branched ketones has been elusive until today. By combining "enol catalysis" with the use of CO2 as a formal catalyst for asymmetric catalysis, we have now developed a solution to this problem: we report a direct, highly enantioselective and highly atom-economic Tsuji-Trost allylation of branched ketones with allylic alcohol. Our reaction delivers products bearing quaternary stereocenters with high enantioselectivity and water as the sole by-product. We expect our methodology to be of utility in asymmetric catalysis and inspire the design of other highly atom-economic transformations. PMID:27071633

  12. Solid radiation curable polyene compositions containing liquid polythiols and solid styrene-allyl copolymer based polyenes

    International Nuclear Information System (INIS)

    Novel styrene-allyl alcohol copolymer based solid polyene compositions which when mixed with liquid polythiols can form solid curable polyene-polythiol systems are claimed. These solid polyenes, containing at least two reactive carbon-to-carbon unsaturated bonds, are urethane or ester derivatives of styrene-allyl alcohol copolymers. The solid polyenes are prepared by treating the hydroxyl groups of a styrene-allyl alcohol copolymer with a reactive unsaturated isocyanate, e.g., allyl isocyanate or a reactive unsaturated carboxylic acid, e.g., acrylic acid. Upon exposure to a free radical generator, e.g., actinic radiation, the solid polyene-polythiol compositions cure to solid, insoluble, chemically resistant, cross-linked polythioether products. Since the solid polyene-liquid polythiol composition can be cured in a solid state, such a curable system finds particular use in preparation of coatings, imaged surfaces such as photoresists, particularly solder-resistant photoresists, printing plates, etc

  13. Total Synthesis of Clavosolide A via Tandem Allylic Oxidation/Oxa-Conjugate Addition Reaction

    Science.gov (United States)

    Baker, Joseph B.; Kim, Hyoungsu; Hong, Jiyong

    2015-01-01

    The tandem allylic oxidation/oxa-conjugate addition reaction promoted by the gem-disubstituent effect in conjunction with the NHC-mediated oxidative esterification was explored for the facile synthesis of clavosolide A. PMID:26236051

  14. Facile synthesis of allyl resinate monomer in an aqueous solution under microwave irradiation

    Indian Academy of Sciences (India)

    Yanju Lu; Mixia Wang; Zhendong Zhao; Yuxiang Chen; Shichao Xu; Jing Wang; Liangwu Bi

    2015-07-01

    We have developed a facile method for production of allyl resinate monomer (allyl rosin ester) via a phase transfer reaction under microwave irradiation. The synthesis of allyl resinate was conducted using allyl chloride and sodium resinate as starting materials in aqueous solution at 50°C for 30 min with a yield of 94.7%, which is 20% higher than conventional heating method. The products precipitated spontaneously from the aqueous phase after reaction, which significantly facilitated the subsequent separation of monomer products. The synthesized monomer product appeared as a viscous liquid, with a viscosity of 460 mPa·s at 25°C and a density of 1.0469 g/cm3. The physical and chemical properties suggested that the synthesized monomer has great potential for free radical polymerization.

  15. Improvement of pesticide adsorption capacity of cellulose fibre by high-energy irradiation-initiated grafting of glycidyl methacrylate

    Science.gov (United States)

    Takács, Erzsébet; Wojnárovits, László; Koczog Horváth, Éva; Fekete, Tamás; Borsa, Judit

    2012-09-01

    Cellulose as a renewable raw material was used for preparation of adsorbent of organic impurities in wastewater treatment. Hydrophobic surface of cellulose substrate was developed by grafting glycidyl methacrylate in simultaneous grafting using gamma irradiation initiation. Water uptake of cellulose significantly decreased while adsorption of phenol and a pesticide molecule (2,4-dichlorophenoxyacetic acid: 2,4-D) increased upon grafting. Adsorption equilibrium data fitted the Freundlich isotherm for both solutes.

  16. Characterization of amyloglucosidase immobilized on the copolymer of ethylene glycol dimethacrylate and glycidyl methacrylate in simulated industrial conditions

    OpenAIRE

    Milosavić Nenad B.; Prodanović Radivoje M.; Jovanović Slobodan M.; Maksimović Vuk M.; Vujčić Zoran M.

    2004-01-01

    The application of amyloglucosidase immobilized on the macroporous co-polymer of ethylene glycol dimethacrylate and glycidyl methacrylate (poly (GMA-co-EGDMA)) in an enzyme reactor was shown. The higher thermostability of immobilized glucoamylases than the soluble one was demonstrated. Immobilized amyloglucosidase obtained by the periodate method shows two times higher thermo stability than the soluble form. Glucoamylases immobilized on poly (GMA-co-EGDMA) have good mechanical and chemical fe...

  17. Improvement of the Thermal, Photo and Mechanical Properties of Poly (Vinyl Chloride) in Presence of Poly (Glycidyl Methacrylate)

    OpenAIRE

    Abir S. Abdel-Naby

    2011-01-01

    Problem statement: Poly (vinyl chloride) suffers from poor heat stability. The thermal degradation of the polymer leads to the evolution of hydrogen chloride gas, extensive discoloration of the polymer and lowering of physical and mechanical properties. Approach: Binary blends of Poly (Vinyl Chloride) (PVC) and Poly (Glycidyl Methacrylate) (PGMA) have been prepared by solution blending aimed at the improvement of thermal and mechanical properties. Results and Conclusion:&#...

  18. Bradykinetic alcohol dehydrogenases make yeast fitter for growth in the presence of allyl alcohol

    OpenAIRE

    Plapp, Bryce V.; Lee, Ann Ting-I.; Khanna, Aditi; Pryor, John M.

    2012-01-01

    Previous studies showed that fitter yeast (Saccharomyces cerevisiae) that can grow by fermenting glucose in the presence of allyl alcohol, which is oxidized by alcohol dehydrogenase I (ADH1) to toxic acrolein, had mutations in the ADH1 gene that led to decreased ADH activity. These yeast may grow more slowly due to slower reduction of acetaldehyde and a higher NADH/NAD+ ratio, which should decrease the oxidation of allyl alcohol. We determined steady-state kinetic constants for three yeast AD...

  19. β-Elimination of an Aziridine to an Allylic Amine: A Mechanistic Study

    OpenAIRE

    Morgan, Kathleen M.; Brown, Garry; Pichon, Monique A.; Green, Geannette Y.

    2011-01-01

    The base-induced rearrangement of aziridines has been examined using a combination of calculations and experiment. The calculations show that the substituent on nitrogen is a critical feature that greatly affects the favorability of both α-deprotonation, and β-elimination to form an allylic amine. Experiments were carried out to determine whether E2-like rearrangement to the allylic amine with lithium diisopropyl amide (LDA) is possible. N-Tosyl aziridines were found to deprotonate on the tos...

  20. Selective epoxidation of allylic alcohols with a titania-silica aerogel

    Energy Technology Data Exchange (ETDEWEB)

    Dusi, M.; Mallat, T.; Baiker, A. [Lab. of Technical Chemistry, Swiss Federal Inst. of Technology, ETH-Zentrum, Zuerich (Switzerland)

    1998-12-31

    An amorphous mesoporous titania-silica aerogel (20 wt%TiO{sub 2} - 80 wt% SiO{sub 2}) and tert.-butylhydroperoxide (TBHP) have been used for the epoxidation of various allylic alcohols. Allylic alcohols possessing an internal double bond were more reactive than those with a terminal C=C bond. Epoxide selectivities could be improved by addition of (basic) zeolite 4 A and NaHCO{sub 3} to the reaction mixture. (orig.)

  1. Highly selective palladium–benzothiazole carbene-catalyzed allylation of active methylene compounds under neutral conditions

    OpenAIRE

    Antonio Monopoli; Pietro Cotugno; Zambonin, Carlo G.; Francesco Ciminale; Angelo Nacci

    2015-01-01

    The Pd–benzothiazol-2-ylidene complex I was found to be a chemoselective catalyst for the Tsuji–Trost allylation of active methylene compounds carried out under neutral conditions and using carbonates as allylating agents. The proposed protocol consists in a simplified procedure adopting an in situ prepared catalyst from Pd2dba3 and 3-methylbenzothiazolium salt V as precursors. A comparison of the performance of benzothiazole carbene with phosphanes and an analogous imidazolium carbene ligand...

  2. Relaxation behavior and nonlinear properties of thermally stable polymers based on glycidyl derivatives of quercetin

    Science.gov (United States)

    Mishurov, Dmytro; Voronkin, Andrii; Roshal, Alexander; Brovko, Oleksandr

    2016-07-01

    Cross-linked polymers on the basis of di-, tri and tetraglycidyl ethers of quercetin (3,3‧,4‧,5,7-pentahydroxyflavone) were synthesized, and then, poled in electrical field of corona discharge. Investigations of structural, thermal and optical parameters of the polymer films were carried out. It was found that the polymers obtained from di- and triglycidyl quercetin ethers had high values of macroscopic quadratic susceptibilities and substantial stability of nonlinear optical (NLO) properties after the poling. Tetraglycidyl ether of quercetin forms the polymer of lower quadratic susceptibility, which demonstrates noticeable relaxation process resulting in decrease of the NLO effect. It is supposed that the difference of the NLO properties is due to peculiarities of physical network of the polymers, namely to the ratio between numbers of hydrogen bonds formed by hydroxyl groups of chromophore fragments and by the ones of interfragmental parts of the polymeric chains.

  3. Palladium-Catalyzed Dearomative Allylic Alkylation of Indoles with Alkynes To Synthesize Indolenines with C3-Quarternary Centers.

    Science.gov (United States)

    Gao, Shang; Wu, Zijun; Fang, Xinxin; Lin, Aijun; Yao, Hequan

    2016-08-01

    A palladium-catalyzed dearomative allylic alkylation of indoles with alkynes to construct indolenines with C3-quarternary centers was reported. The in situ formed arylallene intermediate omitted the need to install leaving groups on the allylic compounds and employ extra oxidants to oxidize the allylic C-H bonds. The reaction exhibited good functional group tolerance and high atom economy. Moreover, the reaction was further expanded to synthesize pyrroloindolines and furanoindolines. PMID:27442021

  4. Impact of PEG and PEG-b-PAGE modified PLGA on nanoparticle formation, protein loading and release.

    OpenAIRE

    Rietscher, René; Czaplewska, Justyna A; Majdanski, Tobias C; Gottschaldt, Michael; Schubert, Ulrich S.; Schneider, Marc; Lehr, Claus-Michael

    2016-01-01

    The effect of modifying the well-established pharmaceutical polymer PLGA by different PEG-containing block-copolymers on the preparation of ovalbumin (OVA) loaded PLGA nanoparticles (NPs) was studied. The used polymers contained poly(d,l-lactic-co-glycolic acid) (PLGA), polyethylene glycol (PEG) and poly(allyl glycidyl ether) (PAGE) as building blocks. The double emulsion technique yielded spherical NPs in the size range from 170 to 220nm (PDI

  5. PEG-b-AGE Polymer Coated Magnetic Nanoparticle Probes with Facile Functionalization and Anti-fouling Properties for Reducing Non-specific Uptake and Improving Biomarker Targeting

    OpenAIRE

    Li, Yuancheng; Lin, Run; Wang, Liya; Huang, Jing; Wu, Hui; Cheng, Guojun; Zhou, Zhengyang; MacDonald, Tobey; Yang, Lily; Mao, Hui

    2015-01-01

    Non-specific surface adsorption of bio-macromolecules (e.g. proteins) on nanoparticles, known as biofouling, and the uptake of nanoparticles by the mononuclear phagocyte system (MPS) and reticuloendothelial system (RES) lead to substantial reduction in the efficiency of target-directed imaging and delivery in biomedical applications of engineered nanomaterials in vitro and in vivo. In this work, a novel copolymer consisting of blocks of poly ethylene glycol and allyl glycidyl ether (PEG-b-AGE...

  6. α-Sulfonyl succinimides: versatile sulfinate donors in Fe-catalyzed, salt-free, neutral allylic substitution.

    Science.gov (United States)

    Jegelka, Markus; Plietker, Bernd

    2011-09-01

    Allyl sulfones are versatile intermediates in organic chemistry. The presence of two distinct functional groups sets the stage for a plethora of subsequent transformations. However, despite these advantages the preparation of regioisomerically enriched sulfones is not easy. The use of sulfinate salts as nucleophiles in substitutions is frequently accompanied by side reactions such as π-bond migration, β-elimination, and so on. Herein we present a preparatively simple way to synthesize a variety of different aryl or alkyl allyl sulfones starting from readily accessible allylic carbonates. By employing aryl or alkyl α-sulfonyl succinimides as sulfinate synthons, mild and regioselective ipso substitution of diverse allylic carbonates was realized. PMID:21818793

  7. Construction of quaternary stereogenic carbon centers through copper-catalyzed enantioselective allylic cross-coupling with alkylboranes.

    Science.gov (United States)

    Hojoh, Kentaro; Shido, Yoshinori; Ohmiya, Hirohisa; Sawamura, Masaya

    2014-05-01

    A combination of an in situ generated chiral Cu(I) /DTBM-MeO-BIPHEP catalyst system and EtOK enabled the enantioselective SN 2'-type allylic cross-coupling between alkylborane reagents and γ,γ-disubstituted primary allyl chlorides with enantiocontrol at a useful level. The reaction generates a stereogenic quaternary carbon center having three sp(3) -alkyl groups and a vinyl group. This protocol allowed the use of terminal alkenes as nucleophile precursors, thus representing a formal reductive allylic cross-coupling of terminal alkenes. A reaction pathway involving addition/elimination of a neutral alkylcopper(I) species with the allyl chloride substrate is proposed. PMID:24668885

  8. Genotoxic and Nongenotoxic Effects of Glycidyl Methacrylate on Human Lung Fibroblast Cells

    Institute of Scientific and Technical Information of China (English)

    XUE-JUN YIN; FU-DE FANG; JIAN-NING XU; CHANG-QI ZOU; FENG-SHENG HE

    2003-01-01

    To evaluate the genotoxic and nongenotoxic effects of short-term exposure to glycidyl mathacrylate (GMA) on human lung fibroblast cells (2BS cells) in vitro. Methods DNA strand breakage was determined by single cell gel electrophoresis, and DNA ladder formation assay and flow cytometric analysis were carried out to detect apoptic responses of cells to GMA exposure.The HPRT gene mutation assay was used to evaluate the mutagenicity, and the effect of GMA on gap junctional intercellular communication (GJIC) in the exposed cells was examined with the scrape loading/dye transfer technique. The ability of GMA to transform 2BS cells was also tested by an in vitro cell transformation assay. Results Exposure to GMA resulted in a dose-dependent increase in DNA strand breaks but not apoptic responses. GMA was also shown to significantly induce HPRT gene mutations and morphological transformation in 2BS cells in vitro. In contrast, GMA produced a concentration-dependent inhibition of GJIC. Conclusions GMA elicits both genotoxic and nongenotoxic effects on 2BS cells in vitro. The induction of DNA damage and gene mutations and inhibition of GJIC by GMA may casually contribute to GMA-induced cell transformation.

  9. Grafting Glycidyl Methacrylate onto Jute Fiber by Irradiation for Adsorption of Dye in Textile Waste Water

    International Nuclear Information System (INIS)

    Grafting copolymerization of glycidyl methacrylate (2, 3 epoxy propyl methacrylate-EPMA) onto jute fiber by pre-irradiation method has been studied. The different factors influenced on grafting degree (GD) such as the monomer concentration, reactive time and absorbed dose were also investigated. The optimal GD was found to be 121% at EPMA concentration of 20% and the absorbed dose of 12.5 kGy for 7 hours at 80 oC. Grafted jute fiber was treated with ethylene diamine (EDA) and phosphoric acid (H3PO4) to open epoxy ring forming functional groups for adsorption. Adsorption capacities (Qmax) were determined to be 77.519 mg/g, 78.740 mg/g and 1.298 mmol/g or 0.459 mg/g for Direct Blue, Direct Yellow and Potassium dichromate or Cr(VI) respectively as calculated with model of Langmuir isotherm. The characteristics of modified jute fiber were confirmed by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM). Values of BOD5, COD and the content of dye in textile waste water of Nam Thanh factory decreased after treating with modified fiber. (author)

  10. Syntheses of Amine Type Adsorbents with Emulsion Graft Polymerization of Glycidyl Methacrylate

    International Nuclear Information System (INIS)

    Radiation-induced graft polymerization is attractive technique for preparing metal-ion adsorbents. This technique enables to introduce aiming function onto trunk polymers such as polymeric films, fibers, nonwoven fabric, and hollow fibers. The reactive monomer of glycidyl methacrylate (GMA) has been widely used for the syntheses of metal-ion adsorbents. This is because the GMA contains an epoxy group which can react easily with amine derivatives. Therefore, GMA-grafted polymer can be converted to various kinds of metal-ions adsorbents. Generally, GMA can be grafted by using organic solvent such as methanol and dimethyl sulfoxide. We found that the emulsion of GMA was available for effective grafting. In this case, the solvent is water so that the emulsion graft polymerization promises to be the green chemistry. In the present study, the GMA was grafted onto polyethylene fiber (PE fiber) in the emulsion system. Polyoxyethylene sorbitan monolaurate (Tween 20) was used as a surfactant to prepare the micelles of GMA in water. Graft polymerization of GMA micelles was investigated on the conditions of the total dose of irradiation, the monomer concentration, the surfactant concentration, the reaction time, and the reaction temperature

  11. Modification of flax fibres by radiation induced emulsion graft copolymerization of glycidyl methacrylate

    Science.gov (United States)

    Moawia, Rihab Musaad; Nasef, Mohamed Mahmoud; Mohamed, Nor Hasimah; Ripin, Adnan

    2016-05-01

    Flax fibres were modified by radiation induced graft copolymerization of glycidyl methacrylate (GMA) by pre-irradiation method in an emulsion medium. The effect of reaction parameters on the degree of grafting (DOG) such as concentration of bleaching agent, absorbed dose, monomer concentration, temperature and reaction time were investigated. The DOG was found to be dependent on the investigated parameters. The incorporation of poly(GMA) grafts in the bleached flax fibres was confirmed by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The structural and mechanical changes were evaluated by X-ray diffraction (XRD) and mechanical tester, respectively. The results revealed that reacting bleached flax fibres irradiated with 20 kGy with 5% GMA emulsion containing 0.5% polyoxyethylene-sorbitan monolaurate (Tween 20) surfactant at 40 °C for 1 h led to a maximum DOG of 148%. The grafted fibres showed sufficient mechanical strength and hydrophobicity which make them promising precursors for development of adsorbents after appropriate chemical treatments.

  12. Graft copolymerization of glycidyl methacrylate onto delignified kenaf fibers through pre-irradiation technique

    International Nuclear Information System (INIS)

    Glycidyl methacrylate grafted kenaf (GMA-g-Kenaf) was prepared by pre-irradiation grafting technique. Kenaf fibers were treated with different concentration of sodium chlorite solution before used as trunk polymer. Treated kenaf fibers were irradiated by electron beam followed by grafting reaction in GMA/water emulsion system. The degree of grafting was determined as a function of absorbed dose, reaction time, reaction temperature and concentration of monomer. The results showed that the lignin content was decreased from 14.3% to as low as 3.3% with the increased of sodium chlorite concentration. This was evidenced by SEM pictures which show the surface of treated kenaf fibers was cleaner and smoother compared to that of untreated one. The degree of grafting increased with the increase of absorbed dose, reaction temperature, reaction time and monomer concentration as well as with decreasing lignin content. Formation of graft copolymer was confirmed with SEM, FTIR analysis. The structural investigation by XRD showed that degree of crystallinity of graft copolymers decreased with the increase in degree of grafting. - Highlights: • We used kenaf fibers for radiation induce graft copolymerization with GMA. • Kenaf fibers was treated to remove lignin in order to increase grafting yield. • Treated kenaf fibers were graft copolymerize through preirradiation technique. • Optimum conditions for graft copolymerization of kenaf fibers were established. • Formation of graft copolymer is also confirmed with SEM, FTIR and XRD

  13. Cellulose functionalization via high-energy irradiation-initiated grafting of glycidyl methacrylate and cyclodextrin immobilization

    International Nuclear Information System (INIS)

    Cotton-cellulose was functionalized using gamma-irradiation-induced grafting of glycidyl methacrylate (GMA) to obtain a hydrophobic cellulose derivative with epoxy groups suitable for further chemical modification. Two grafting techniques were applied. In pre-irradiation grafting (PIG) cellulose was irradiated in air and then immersed in a GMA monomer solution, whereas in simultaneous grafting (SG) cellulose was irradiated in an inert atmosphere in the presence of the monomer. PIG led to a more homogeneous fiber surface, while SG resulted in higher grafting yield but showed clear indications of some GMA-homopolymerization. Effects of the reaction parameters (grafting method, absorbed dose, monomer concentration, solvent composition) were evaluated by SEM, gravimetry (grafting yield) and FTIR spectroscopy. Water uptake of the cellulose decreased while adsorption of a pesticide molecule increased upon grafting. The adsorption was further enhanced by β-cyclodextrin immobilization during SG. This method can be applied to produce adsorbents from cellulose based agricultural wastes. - Highlights: → Fundamentals of two grafting methods for biomass utilization as adsorbents. → Simultaneous grafting is more efficient and useful than the pre-irradiation one. → Methanol/water/surfactant combined solvent gives the best grafting yield. → Grafted cellulose increased hydrophobicity and adsorption of phenolic compounds. → Improved adsorption by bonding β-cyclodextrin during simultaneous grafting.

  14. Soybean hull peroxidase immobilization on macroporous glycidyl methacrylates with different surface characteristics.

    Science.gov (United States)

    Prokopijevic, Milos; Prodanovic, Olivera; Spasojevic, Dragica; Stojanovic, Zeljko; Radotic, Ksenija; Prodanovic, Radivoje

    2014-05-01

    Soybean hull peroxidase (SHP, E.C. 1.11.1.7) was immobilized by a glutaraldehyde and periodate method onto series of macroporous copolymers of glycidyl methacrylate (GMA) and ethylene glycol dimethacrylate (EGDMA), poly(GMA-co-EGDMA) with various surface characteristics and pore size diameters ranging from 44 to 200 nm. Glutaraldehyde immobilization method and poly(GMA-co-EGDMA) named SGE 20/12 with pore sizes of 120 nm gave immobilized enzyme with highest specific activity of 25 U/g. Deactivation studies showed that immobilization increased stability of SHP and that surface characteristics of the used copolymer had a major influence on a stability of immobilized enzyme at high temperatures and in an organic solvent. The highest thermostability was obtained using the copolymer SGE 20/12 with pore size of 120 nm, while the highest stability in dioxane had SHP immobilized onto copolymer SGE 10/4 with pore size of 44 nm. Immobilized SHP showed a wider pH optimum as compared to the native enzyme especially at alkaline pH values and 3.2 times increased K m value for pyrogallol. After 6 cycles of repeated use in batch reactor, immobilized SHP retained 25 % of its original activity. Macroporous copolymers with different surface characteristics can be used for fine tuning of activity and stability of immobilized SHP to obtain a biocatalyst suitable for phenol oxidation or polymer synthesis in organic solvents. PMID:24061564

  15. Improved covalent immobilization of horseradish peroxidase on macroporous glycidyl methacrylate-based copolymers.

    Science.gov (United States)

    Prodanović, Olivera; Prokopijević, Miloš; Spasojević, Dragica; Stojanović, Zeljko; Radotić, Ksenija; Knežević-Jugović, Zorica D; Prodanović, Radivoje

    2012-11-01

    A macroporous copolymer of glycidyl methacrylate and ethylene glycol dimethacrylate, poly(GMA-co-EGDMA), with various surface characteristics and mean pore size diameters ranging from 44 to 200 nm was synthesized, modified with 1,2-diaminoethane, and tested as a carrier for immobilization of horseradish peroxidase (HRP) by two covalent methods, glutaraldehyde and periodate. The highest specific activity of around 35 U g(-1) dry weight of carrier was achieved on poly(GMA-co-EGDMA) copolymers with mean pore diameters of 200 and 120 nm by the periodate method. A study of deactivation kinetics at 65 °C and in 80 % dioxane revealed that periodate immobilization also produced an appreciable stabilization of the biocatalyst, while stabilization factor depended strongly on the surface characteristics of the copolymers. HRP immobilized on copolymer with a mean pore diameter of 120 nm by periodate method showing not only the highest specific activity but also good stability was further characterized. It appeared that the immobilization resulted in the stabilization of enzyme over a broader pH range while the Michaelis constant value (K (m)) of the immobilized HRP was 10.8 mM, approximately 5.6 times higher than that of the free enzyme. After 6 cycles of repeated use in a batch reactor for pyrogallol oxidation, the immobilized HRP retained 45 % of its original activity. PMID:22941271

  16. Glycidyl methacrylate macroporous copolymer grafted with diethylene triamine as sorbent for Reactive Black 5

    Directory of Open Access Journals (Sweden)

    Sandić Zvjezdana P.

    2014-01-01

    Full Text Available In this paper, macroporous glycidyl methacrylate and ethylene glycol dimethacrylate copolymer functionalized with diethylene triamine [PGME-deta], was evaluated as Reactive Black 5 (RB5 sorbent. Batch RB5 removal from aqueous solution by PGME-deta was investigated by varying pH, contact time, sorbent dosage, initial dye concentration and temperature. The sorption is pH sensitive having maximum at pH 2 (dye removal of 85%, decreasing with the increase of pH (dye removal of 24% at pH=11 after 60 min. Sorption kinetics was fitted to chemical-reaction and particle-diffusion models (pseudo-first-order, pseudo-second-order, intraparticle diffusion and Mckay models. The pseudo-second-order kinetic model accurately predicted the RB5 amount sorbed under all investigated operating conditions, while the intraparticle diffusion was the dominant rate-limiting mechanism. The diffusion mechanism was more prevalent with the decrease in temperature and the increase in concentration. The isotherm data was best fitted with the Langmuir model, indicating homogeneous distribution of active sites on PGME-deta and monolayer sorption, with the maximum sorption capacity of 353 mg g-1. The calculated sorption rates improved with increasing temperature and an activation energy close to 40 kJ mol-1 was determined, suggesting that chemisorption was also rate-controlling. [Projekat Ministarstva nauke Republike Srbije, br. III 43009, br. TR 37021 i br. III 45001

  17. Allyl isothiocyanate enhances shelf life of minimally processed shredded cabbage.

    Science.gov (United States)

    Banerjee, Aparajita; Penna, Suprasanna; Variyar, Prasad S

    2015-09-15

    The effect of allyl isothiocyanate (AITC), in combination with low temperature (10°C) storage on post harvest quality of minimally processed shredded cabbage was investigated. An optimum concentration of 0.05μL/mL AITC was found to be effective in maintaining the microbial and sensory quality of the product for a period of 12days. Inhibition of browning was shown to result from a down-regulation (1.4-fold) of phenylalanine ammonia lyase (PAL) gene expression and a consequent decrease in PAL enzyme activity and o-quinone content. In the untreated control samples, PAL activity increased following up-regulation in PAL gene expression that could be linearly correlated with enhanced o-quinone formation and browning. The efficacy of AITC in extending the shelf life of minimally processed shredded cabbage and its role in down-regulation of PAL gene expression resulting in browning inhibition in the product is reported here for the first time. PMID:25863635

  18. Synthesis of thermosensitive magnetic nanocarrier for controlled sorafenib delivery.

    Science.gov (United States)

    Heidarinasab, Amir; Ahmad Panahi, Homayon; Faramarzi, Mehdi; Farjadian, Fatemeh

    2016-10-01

    Allyl glycidyl ether/N-isopropylacrylamide-grafted magnetic nanoparticles were prepared using silica-coated magnetic nanoparticles as a substrate for radical copolymerization of allyl glycidyl ether and N-isopropylacrylamide. Chitosan was coupled with the prepared nanoparticles by opening the epoxy ring of the allyl glycidyl ether. The thermosensitive magnetic nanocarrier (TSMNC) obtained can be applied as a potent drug carrier. The TSMNC structure was characterized using Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, vibrating sample magnetometer, and elemental analysis. Its morphology and size were investigated using field emission scanning electron microscopy, transmission electron microscopy and dynamic light scattering. The feasibility of employing the TSMNC for adsorption and in vitro controlled release of the chemotherapeutic agent sorafenib was tested. The effect of the adsorption parameters of pH, temperature, and loading time of sorafenib onto TSMNC was evaluated. The adsorption data was fitted to the Langmuir and Freundlich isotherms and the relevant parameters derived. The drug release profile indicated that 88% of the adsorbed drug was released within 35h at 45°C and drug release was Fickian diffusion-controlled. The results confirmed that the TSMNC has a high adsorption capacity at low temperature and good controlled release in a slow rate at a high temperature and could be developed for further application as a drug nanocarrier. PMID:27287097

  19. The simple ethers of glycerin

    International Nuclear Information System (INIS)

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

  20. Rapid formation of β-allyl substituted isotetronic acid derivatives via Claisen rearrangement using a microfludic device

    Institute of Scientific and Technical Information of China (English)

    Xia Ping Ma; Zhi Ming Li; Quan Rui Wang

    2011-01-01

    The thermal Claisen rearrangement of O-allyl substituted isotetronic acids 1 was successfully carried out within a glass microreactor operated with temperature at 150 ℃ and a flow rate of 1 mL/h. The strategy provides an efficient alternative way to β-allyl substituted isotetronic acid derivatives 2 in high yields with much accelerated reaction speed.

  1. Dicyano-Functionalized MCM-41-Supported Palladium Complex as An Efficient Catalyst for Allylation of Aldehydes and Ketones

    Institute of Scientific and Technical Information of China (English)

    ZHAO Hong; CAI Ming-Zhong

    2006-01-01

    Dicyano-functionalized MCM-41-supported palladium complex was prepared from dicyano-functionalized MCM-41 and palladium chloride. This complex exhibited high catalytic activity in the allylation of aldehydes and ketones with allylic chlorides in the presence of SnCl2. This polymeric palladium complex can be recovered and reused without noticeable loss of activity.

  2. High performance protein microarrays based on glycidyl methacrylate-modified polyethylene terephthalate plastic substrate.

    Science.gov (United States)

    Liu, Yingshuai; Li, Chang Ming; Hu, Weihua; Lu, Zhisong

    2009-01-15

    There is a great challenge to immobilize high density of probe molecules for high performance protein microarrays, and this is achieved in this work by using polyethylene terephthalate (PET) plastic substrate onto which glycidyl methacrylate (GMA) photopolymer is grafted under mild conditions to introduce high density of epoxy groups for covalent immobilization of proteins. The poly(GMA)-grafted PET (PGMA-PET) surface was characterized with atomic force microscope (AFM) and attenuated total reflectance Fourier transform infra-red (ATR-FTIR) spectroscopy. For high density of protein immobilization and good quality of microspots, experiments were conducted to optimize the printing buffer, and an optimal buffer was found out to be PBS with 10% glycerol+0.003% triton X-100. According to the studies of loading capacity and immobilization kinetics, the optimal protein probe concentration and incubation time for the efficient immobilization are 200 microg mL(-1) and 8h, respectively. The performance of the PGMA-PET-based protein microarrays is evaluated with sandwich immunoassay using rat IgG and anti-rat IgG as model proteins, demonstrating a limit of detection (LOD) of 10 pg mL(-1) and a dynamic range of five orders of magnitude which are better than or very comparable with the reported or commercially available immunoassays, while providing a high-throughput approach. The work renders a simple and economic method to manufacture high performance protein microarrays and is expected to have great potentials in broad applications related to clinic diagnosis, drug discovery and proteomic research. PMID:19064107

  3. Characterization of glycidyl methacrylate - crosslinked hyaluronan hydrogel scaffolds incorporating elastogenic hyaluronan oligomers.

    Science.gov (United States)

    Ibrahim, S; Kothapalli, C R; Kang, Q K; Ramamurthi, A

    2011-02-01

    Prior studies on two-dimensional cell cultures suggest that hyaluronic acid (HA) stimulates cell-mediated regeneration of extracellular matrix structures, specifically those containing elastin, though such biologic effects are dependent on HA fragment size. Towards being able to regenerate three-dimensional (3-D) elastic tissue constructs, the present paper studies photo-crosslinked hydrogels containing glycidyl methacrylate (GM)-derivatized bio-inert high molecular weight (HMW) HA (1 × 10(6)Da) and a bioactive HA oligomer mixture (HA-o: MW ∼0.75 kDa). The mechanical (rheology, degradation) and physical (apparent crosslinking density, swelling ratio) properties of the gels varied as a function of incorporated HA oligomer content; however, overall, the mechanics of these hydrogels were too weak for vascular applications as stand-alone materials. Upon in vivo subcutaneous implantation, only a few inflammatory cells were evident around GM-HA gels, however their number increased as HA-o content within the gels increased, and the collagen I distribution was uniform. Smooth muscle cells (SMC) were encapsulated into GM hydrogels, and calcein acetoxymethyl detection revealed that the cells were able to endure twofold the level of UV exposure used to crosslink the gels. After 21 days of culture, SMC elastin production, measured by immunofluorescence quantification, showed HA-o to increase cellular deposition of elastic matrix twofold relative to HA-o-free GM-HA gels. These results demonstrate that cell response to HA/HA-o is not altered by their methacrylation and photo-crosslinking into a hydrogel, and that HA-o incorporation into cell-encapsulating hydrogel scaffolds can be useful for enhancing their production of elastic matrix structures in a 3-D space, important for regenerating elastic tissues. PMID:20709199

  4. Synthesis and characterization of monosize magnetic poly(glycidyl methacrylate) beads

    Institute of Scientific and Technical Information of China (English)

    Evrim Banu Alt1nta(s); Lokman Uzun; Adil Denizli

    2007-01-01

    Monosize, 1.6 μm, magnetic beads of poly(glycidyl methacrylate) [M-poly(GMA)], were prepared by dispersion polymerization in the presence of Fe3O4 nano-powder. Monosize M-poly(GMA) beads were characterized by swelling tests, density measurements, electron spin resonance (ESR), vibrating sample magnetometer (VSM) and scanning electron microscopy (SEM). The characteristic functional groups of M-poly(GMA)beads were analyzed by Fourier transform infrared spectrometer (FTIR). The M-poly(GMA) beads are highly uniform in size and have a spherical shape and non-porous structure. Polydispersity index (PDI) of M-poly(GMA) beads was calculated to be around 1.008. The hydrated density of the M-poly(GMA) beads measured at 25 ℃ was 1.14 g/cm3. The content of oxirane groups on the surface of the M-poly(GMA) sample was found to be 3.46 mmol/g by using perchloric acid titration. The specific surface area of the M-poly(GMA) beads was determined to be 3.2 m2/g.The equilibrium swelling ratio was 52%. The volume fraction of magnetite nanopowder in the M-poly(GMA) beads was found to be 4.5%. The g factor, that can be considered as a quantity characteristic of the molecules in which the unpaired electrons are located, was found to be 2.28for M-poly(GMA). The external magnetic field at resonance was calculated to be 2055 Gs which was found sufficient to excite all of the dipole moments present in 1.0 g of M-poly(GMA) sample.

  5. Composite glycidyl methacrylated dextran (Dex-GMA)/gelatin nanoparticles for localized protein delivery

    Institute of Scientific and Technical Information of China (English)

    Fa-ming CHEN; Zhi-wei MA; Guang-ying DONG; Zhi-fen WU

    2009-01-01

    Aim: Localized delivery of growth factors has significant potential as a future therapeutic strategy in tissue engineering and regenerative medicine. A nanoparticle vehicle was created and evaluated in this study with the intent to deliver growth factors for periodontal regeneration. Methods: Novel composite nanoparticles based on glycidyl methacrylate derivatized dextrans (Dex-GMA) and gelatin were fabricated by a facile method without using any organic solvents. The configurations of the resultant nanoparticles were evaluated by transmission electron microscopy, scanning electron microscopy, and atomic force microscope. Their surfaces were characterized by zeta-potential measurements, after which their properties including swelling, degradation, drug release, and cytotoxicity were also investigated using in vitro models,Results: The particle size of Dex-GMA/gelatin nanoparticles (DG-NPs) ranged from 20 to 100 nm and showed a mono-dis-perse size distribution (mean diameter 53.7 nm) and a strongly negative surface zeta potential (-20 mV). The DC,-NPs were characterized by good swelling and degradation properties in media including dextranase. The in vitro drug release stud-ies showed that the efficient bone morphogenetic protein (BMP) release from DG-NPs was maintained for more than 12 d under degradation conditions, where more than 90% of the loaded BMP was released. No any relevant cell damage caused by DG-NPs was found in the cytotoxicity tests for a period of 24 h.Conclusion: These combined results demonstrate that DG-NPs fulfill the basic prerequisites for growth factor delivery.With further in vivo studies, those nanoparticles may offer a promising vehicle for the delivery of active drugs to the perio-dontium.

  6. PEGylation of magnetic poly(glycidyl methacrylate) microparticles for microfluidic bioassays

    Energy Technology Data Exchange (ETDEWEB)

    Kucerova, Jana; Svobodova, Zuzana [Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 53210 Pardubice (Czech Republic); Knotek, Petr [Joint Laboratory of Solid State Chemistry of IMC and University of Pardubice, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 53210 Pardubice (Czech Republic); Palarcik, Jiri [Institute of Environmental and Chemical Engineering, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 53210 Pardubice (Czech Republic); Vlcek, Milan; Kincl, Miloslav; Horak, Daniel [Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovsky Sq. 2, 16206 Prague 6 (Czech Republic); Autebert, Julien; Viovy, Jean-Louis [Macromolecules and Microsystems in Biology and Medicine, Institute Curie, UMR 168, 26 Rue d' Ulm, 75005 Paris (France); Bilkova, Zuzana, E-mail: zuzana.bilkova@upce.cz [Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 53210 Pardubice (Czech Republic)

    2014-07-01

    In this study, magnetic poly(glycidyl methacrylate) microparticles containing carboxyl groups (PGMA-COOH) were coated using highly hydrophilic polymer poly(ethylene glycol) (PEG). PEG was used to reduce nonspecific interactions with proteins and cells while decreasing adhesion of particles to the walls of a microfluidic devices from poly(dimethylsiloxane) (PDMS) and cyclic olefin copolymer (COC). Zeta potential measurement, infrared spectroscopy, scanning electron microscopy, anti-PEG ELISA assay, and bioaffinity interactions between biotin and streptavidin-HRP successfully proved the presence of PEG on the surface of microspheres. Both neat and PEGylated microspheres were then incubated with the inert protein bovine serum albumin or cells to evaluate the rate of nonspecific adsorption (NSA). PEG with Mr of 30,000 Da was responsible for 45% reduction in NSA of proteins and 74% for cells compared to neat particles. The microspheres' behavior in PDMS and COC microchannels was then evaluated. Aggregation and adhesion of PEGylated microspheres significantly decreased compared to neat particles. Finally, the model enzyme horseradish peroxidase was immobilized on the microspheres through the heterobifunctional PEG chain. The possibility for subsequent covalent coupling of the ligand of interest was confirmed. Such PEGylated microparticles can be efficiently used in PDMS microchips as a carrier for bioaffinity separation or of enzyme for catalysis. - Highlights: • Magnetic polymer microspheres with highly hydrophilic PEG coating were prepared. • PEG reduced microsphere adhesion in microchannels versus neat particles. • Suitability of methods for detecting PEG on magnetic microspheres was investigated. • PEG on microsphere surfaces decreased nonspecific adsorption of proteins and cells.

  7. Poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate)/clay composites

    International Nuclear Information System (INIS)

    Highlights: → We synthesized macroporous composites of poly(GMA-co-EGDMA) and either raw or acid modified clay. → Morphological, textural and thermal properties of the composite with acid modified clay were significantly changed with retained macroporosity. → Composite with raw clay has enhanced thermal stability. - Abstract: In this study, macroporous composites of poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) i.e. poly(GMA-co-EGDMA) and clay were prepared by radical suspension copolymerization. The composites with either raw (S0) or acid-modified clay (SA) were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric (TG) and textural analysis. The morphological, textural and thermal properties of the composite with raw clay (CP-S0) differed slightly from those of the copolymer (CP), with exception of the thermal stability expressed in the shifting of the initial degradation temperature from 125 deg. C for CP to 210 deg. C for CP-S0. On the other hand, composite with modified clay (CP-SA) was a material with significantly changed morphology, porous structure parameters and a qualitatively different thermal behavior in comparison to CP and CP-S0. CP-SA had mass residue, after heating at 600 deg. C, three times higher than the amount of SA introduced into the reaction system. This indicates a different manner of incorporation of SA, compared to S0, into the composite. Both the obtained composites retained their macroporosity and might be used in all applications that involve macroporous copolymers and, due to the altered thermal properties, their application may be extended.

  8. How phenyl makes a difference: mechanistic insights into the ruthenium( ii )-catalysed isomerisation of allylic alcohols

    KAUST Repository

    Manzini, Simone

    2013-10-16

    [RuCl(η5-3-phenylindenyl)(PPh3)2] (1) has been shown to be a highly active catalyst for the isomerisation of allylic alcohols to the corresponding ketones. A variety of substrates undergo the transformation, typically with 0.25-0.5 mol% of catalyst at room temperature, outperforming commonly-used complexes such as [RuCl(Cp)(PPh3) 2] and [RuCl(η5-indenyl)(PPh3) 2]. Mechanistic experiments and density functional theory have been employed to investigate the mechanism and understand the effect of catalyst structure on reactivity. These investigations suggest a oxo-π-allyl mechanism is in operation, avoiding intermediate ruthenium hydride complexes and leading to a characteristic 1,3-deuterium shift. Important mechanistic insights from DFT and experiments also allowed for the design of a protocol that expands the scope of the transformation to include primary allylic alcohols. © 2013 The Royal Society of Chemistry.

  9. Study on the Synthesis of Cardanol Glycidyl Ether%腰果酚缩水甘油醚的工艺技术研究

    Institute of Scientific and Technical Information of China (English)

    张明伟; 王宏力; 赵立新; 郭歌; 田倩倩

    2013-01-01

    以腰果酚和环氧氯丙烷为主要原料,在催化剂苄基三乙基氯化铵的催化下合成了腰果酚缩水甘油醚.考察了反应条件对环氧值的影响,通过正交试验和单因素试验确定了合成腰果酚缩水甘油醚的适宜工艺条件为:n(腰果酚)∶n(环氧氯丙烷)∶n(氢氧化钠)=1∶5∶1.2,醚化温度为80℃,醚化时间为4h,闭环温度为60℃,闭环时间为3h,催化剂为腰果酚质量的2%,腰果酚缩水甘油醚的环氧值高达到0.279并且收率达到85.6%.

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

    Science.gov (United States)

    Demir, Teyfik

    2015-05-01

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

  11. Asymmetric epoxidation of allylic alcohols catalyzed by vanadium-binaphthylbishydroxamic Acid complex.

    Science.gov (United States)

    Noji, Masahiro; Kobayashi, Toshihiro; Uechi, Yuria; Kikuchi, Asami; Kondo, Hisako; Sugiyama, Shigeo; Ishii, Keitaro

    2015-03-20

    A vanadium-binaphthylbishydroxamic acid (BBHA) complex-catalyzed asymmetric epoxidation of allylic alcohols is described. The optically active binaphthyl-based ligands BBHA 2a and 2b were synthesized from (S)-1,1'-binaphthyl-2,2'-dicarboxylic acid and N-substituted-O-trimethylsilyl (TMS)-protected hydroxylamines via a one-pot, three-step procedure. The epoxidations of 2,3,3-trisubstituted allylic alcohols using the vanadium complex of 2a were easily performed in toluene with a TBHP water solution to afford (2R)-epoxy alcohols in good to excellent enantioselectivities. PMID:25714329

  12. Highly selective palladium–benzothiazole carbene-catalyzed allylation of active methylene compounds under neutral conditions

    Directory of Open Access Journals (Sweden)

    Antonio Monopoli

    2015-06-01

    Full Text Available The Pd–benzothiazol-2-ylidene complex I was found to be a chemoselective catalyst for the Tsuji–Trost allylation of active methylene compounds carried out under neutral conditions and using carbonates as allylating agents. The proposed protocol consists in a simplified procedure adopting an in situ prepared catalyst from Pd2dba3 and 3-methylbenzothiazolium salt V as precursors. A comparison of the performance of benzothiazole carbene with phosphanes and an analogous imidazolium carbene ligand is also proposed.

  13. Kinetic Studies that Evaluate the Solvolytic Mechanisms of Allyl and Vinyl Chloroformate Esters

    Directory of Open Access Journals (Sweden)

    Malcolm J. D'Souza

    2013-04-01

    Full Text Available At 25.0 °C the specific rates of solvolysis for allyl and vinyl chloroformates have been determined in a wide mix of pure and aqueous organic mixtures. In all the solvents studied, vinyl chloroformate was found to react significantly faster than allyl chloroformate. Multiple correlation analyses of these rates are completed using the extended (two-term Grunwald-Winstein equation with incorporation of literature values for solvent nucleophilicity (NT and solvent ionizing power (YCl. Both substrates were found to solvolyze by similar dual bimolecular carbonyl-addition and unimolecular ionization channels, each heavily dependent upon the solvents nucleophilicity and ionizing ability.

  14. Transient overexpression of adh8a increases allyl alcohol toxicity in zebrafish embryos.

    Science.gov (United States)

    Klüver, Nils; Ortmann, Julia; Paschke, Heidrun; Renner, Patrick; Ritter, Axel P; Scholz, Stefan

    2014-01-01

    Fish embryos are widely used as an alternative model to study toxicity in vertebrates. Due to their complexity, embryos are believed to more resemble an adult organism than in vitro cellular models. However, concerns have been raised with respect to the embryo's metabolic capacity. We recently identified allyl alcohol, an industrial chemical, to be several orders of magnitude less toxic to zebrafish embryo than to adult zebrafish (embryo LC50 = 478 mg/L vs. fish LC50 = 0.28 mg/L). Reports on mammals have indicated that allyl alcohol requires activation by alcohol dehydrogenases (Adh) to form the highly reactive and toxic metabolite acrolein, which shows similar toxicity in zebrafish embryos and adults. To identify if a limited metabolic capacity of embryos indeed can explain the low allyl alcohol sensitivity of zebrafish embryos, we compared the mRNA expression levels of Adh isoenzymes (adh5, adh8a, adh8b and adhfe1) during embryo development to that in adult fish. The greatest difference between embryo and adult fish was found for adh8a and adh8b expression. Therefore, we hypothesized that these genes might be required for allyl alcohol activation. Microinjection of adh8a, but not adh8b mRNA led to a significant increase of allyl alcohol toxicity in embryos similar to levels reported for adults (LC50 = 0.42 mg/L in adh8a mRNA-injected embryos). Furthermore, GC/MS analysis of adh8a-injected embryos indicated a significant decline of internal allyl alcohol concentrations from 0.23-58 ng/embryo to levels below the limit of detection (< 4.6 µg/L). Injection of neither adh8b nor gfp mRNA had an impact on internal allyl alcohol levels supporting that the increased allyl alcohol toxicity was mediated by an increase in its metabolization. These results underline the necessity to critically consider metabolic activation in the zebrafish embryo. As demonstrated here, mRNA injection is one useful approach to study the role of candidate enzymes involved in

  15. Synthesis of (-)-Piperitylmagnolol Featuring ortho-Selective Deiodination and Pd-Catalyzed Allylation.

    Science.gov (United States)

    Ikoma, Atsushi; Ogawa, Narihito; Kondo, Daiki; Kawada, Hiroki; Kobayashi, Yuichi

    2016-05-01

    A 1,4-addition strategy using an enone and a copper reagent was studied for the synthesis of (-)-piperitylmagnolol. A MOM-protected biphenol copper reagent was added to BF3·OEt2-activated 4-isopropylcyclohexenone, whereas 1,4-addition of protected monophenol reagents possessing an allyl group was found to be unsuccessful. The allyl group was later attached to the p-,p'-diiodo-biphenol ring by Pd-catalyzed coupling with allylborate. The aforementioned iodide was synthesized using a new method for ortho-selective deiodination of o-,p-diiodophenols. PMID:27109890

  16. Ether symmetry unification theory (ESU)

    International Nuclear Information System (INIS)

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

  17. Congested C-C Bonds by Pd-Catalyzed Enantioselective Allyl-Allyl Cross-Coupling, A Mechanism-Guided Solution

    OpenAIRE

    Ardolino, Michael J.; Morken, James P.

    2014-01-01

    Under the influence of a chiral bidentate diphosphine ligand, the Pd-catalyzed asymmetric cross-coupling of allylboron reagents and allylic electrophiles establishes 1,5-dienes with adjacent stereocenters in high regio- and stereoselectivity. . A mechanistic study of the coupling utilizing reaction calorimetry and density functional theory analysis suggests that the reaction operates through an inner-sphere 3,3'-reductive elimination pathway, which is both rate- and stereodefining. Coupled wi...

  18. Development of erbium phosphate doped poly(glycidyl methacrylate/ethylene dimethacrylate) spin columns for selective enrichment of phosphopeptides.

    Science.gov (United States)

    Güzel, Yüksel; Rainer, Matthias; Messner, Christoph B; Hussain, Shah; Meischl, Florian; Sasse, Michael; Tessadri, Richard; Bonn, Günther K

    2015-05-01

    In this study, a novel method for the highly selective enrichment of phosphopeptides using erbium phosphate doped poly(glycidyl methacrylate/ethylene dimethacrylate) spin columns is presented. Erbium phosphate was synthesized by precipitation from boiling phosphoric acid and incubated overnight in erbium chloride solutions. The resulting powder was embedded in a monolithic poly(glycidyl methacrylate/ethylene dimethacrylate) polymer. The monolith was synthesized in a spin column by radical polymerization. Erbium phosphate demonstrated a high affinity and selectivity for phosphopeptides due to the strong interaction of trivalent erbium ions with the phosphate groups of phosphopeptides. The high selectivity and performance of the designed spin columns were demonstrated by successfully enriching phosphopeptides from tryptically digested protein mixtures containing the model phosphoproteins α- and β-casein, bovine milk, and human saliva. By the implementation of several washing steps, unspecific components were removed and the enriched phosphopeptides were effectively eluted from the spin columns under alkaline conditions. The selective performance of the presented method was further demonstrated by the enrichment of two synthetic phosphopeptides, which were spiked in tryptically digested and dephosphorylated HeLa cell lysates at low ratios. Finally, the presented approach was compared to conventional phosphopeptide enrichment by titanium oxide and revealed higher recoveries for the erbium phosphate doped monoliths. PMID:25645427

  19. Solvent-Controlled, Tunable β-OAc and β-H Elimination in Rh(III)-Catalyzed Allyl Acetate and Aryl Amide Coupling via C-H Activation.

    Science.gov (United States)

    Dai, Huimin; Yu, Chao; Wang, Zihao; Yan, Hong; Lu, Changsheng

    2016-07-15

    The Heck reaction between arenes and allyl acetate has led to cinnamyl derivatives and allyl products depending on the regioselectivity of β-elimination. The regioselectivity can be controlled by the solvent in the Rh(III)-catalyzed arene-allyl acetate coupling via C-H activation: (1) in THF, cinnamyl derivatives via β-H elimination were generated; (2) in MeOH, allyl products via β-OAc elimination were produced. Both routes have advantages such as excellent γ-selectivity toward allyl acetate, good to excellent yields, and broad substrate scope. PMID:27351917

  20. Grafting glycidyl methacrylate to Sepharose gel for fabricating high-capacity protein anion exchangers.

    Science.gov (United States)

    Wang, Qianqian; Yu, Linling; Sun, Yan

    2016-04-22

    To develop ion exchangers of high protein adsorption capacity, we have herein introduced atom transfer radical polymerization (ATRP) method to graft glycidyl methacrylate (GMA) onto Sepharose FF gel. GMA-grafted Sepharose FF resins of four grafting densities and different grafting chain lengths were obtained by adjusting reaction conditions. The epoxy groups on the grafted chains were functionalized by modification with diethylamine (DEA), leading to the fabrication of Sepharose-based anion exchangers of 14 different grafting densities and/or grafting chain lengths. The resins were first characterized for the effects of grafting density, chain length and ionic strength on pore sizes by inverse size exclusion chromatography. Then, the resins were evaluated by adsorption equilibria of bovine serum albumin (BSA) as a function of ionic capacity (IC) (chain length) at individual grafting densities. It was observed that at each grafting density there was a specific IC value (chain length) that offered the maximum equilibrium capacity. Of the resins with maximum values at individual grafting densities, the resin of the second grafting density with an IC value of 330 mmol/L (denoted as FF-Br2-pG-D330) showed the highest capacity, 264 mg/mL, about two times higher than that of the traditional ungrafted resin Q Sepharose FF (137 mg/mL). This resin also showed the most favorable uptake kinetics among the resins of similar IC values but different grafting densities, or of the same grafting density but different IC values. Effects of ionic strength showed that the capacities of FF-Br2-pG-D330 were much higher than Q Sepharose FF at a wide range of NaCl concentrations (0-200 mmol/L), and the uptake rates of the two resins were similar in the ionic strength range. Therefore, the dynamic binding capacity values of BSA on FF-Br2-pG-D330 were much higher than Q Sepharose FF as demonstrated at different residence times and ionic strengths. Taken together, the research has proved the

  1. Polymerization of oligo(ethylene glycol) methacrylate from monodisperse poly(glycidyl methacrylate) microsphers to reduce non-specific protein adsorption

    Czech Academy of Sciences Publication Activity Database

    Grama, Silvia; Heuts, H.; Horák, Daniel

    Riva del Garda : Elsevier, 2015. P2.010. [International Symposium Frontiers in Polymer Science /4./ - POLY 2015. 20.05.2015-22.05.2015, Riva del Garda] R&D Projects: GA MŠk(CZ) EE2.3.30.0029 Institutional support: RVO:61389013 Keywords : microspheres * poly(glycidyl methacrylate) * atom transfer radical polymerization Subject RIV: CE - Biochemistry

  2. Controllable Biotinylated Poly(Ethylene-co-Glycidyl Methacrylate) (PE-co-GMA) Nanofibers to Bind Streptavidin-Horseradish Peroxidase (HRP) for Potential Biosensor Applications

    Science.gov (United States)

    Poly(ethylene-co-glycidyl methacrylate) (PE-co-GMA) nanofibers with abundant active epoxy groups on surfaces were fabricated through a novel manufacturing process. The prepared PE-co-GMA nanofibers with different average diameters ranging from 100 to 400 nm were aminated by reacting the epoxy groups...

  3. Poly(glycidyl methacrylate)/silver nanocomposite microspheres as a radioiodine scavenger: electrophoretic characterisation of carboxyl- and amine-modified particles

    Czech Academy of Sciences Publication Activity Database

    Macková, Hana; Oukacine, F.; Plichta, Zdeněk; Hrubý, Martin; Kučka, Jan; Taverna, M.; Horák, Daniel

    2014-01-01

    Roč. 421, 1 May (2014), s. 146-153. ISSN 0021-9797 R&D Projects: GA MŠk 7E12053; GA ČR GAP503/10/0664 EU Projects: European Commission(XE) 246513 - NADINE Institutional support: RVO:61389013 Keywords : glycidyl methacrylate * microspheres * silver Subject RIV: CD - Macromolecular Chemistry Impact factor: 3.368, year: 2014

  4. Poly(glycidyl methacrylate) microspheres: preparation by poly(acrylic acid)-stabilized dispersion polymerization and effect of some reaction parameters

    Czech Academy of Sciences Publication Activity Database

    Koubková, Jana; Horák, Daniel

    2013-01-01

    Roč. 2, č. 3 (2013), s. 218-225. ISSN 2164-9634 R&D Projects: GA ČR GCP207/12/J013 Institutional support: RVO:61389013 Keywords : glycidyl methacrylate * dispersion polymerization * poly(acrylic acid) Subject RIV: CD - Macromolecular Chemistry

  5. Immunocapture of CD133-positive cells from human cancer cell lines by using monodisperse magnetic poly(glycidyl methacrylate) microspheres containing amino groups

    Czech Academy of Sciences Publication Activity Database

    Kuan, W.-C.; Horák, Daniel; Plichta, Zdeněk; Lee, W.-C.

    2014-01-01

    Roč. 34, 1 January (2014), s. 193-200. ISSN 0928-4931 R&D Projects: GA ČR GCP207/12/J013 Institutional support: RVO:61389013 Keywords : magnetic * poly(glycidyl methacrylate) * microspheres Subject RIV: CD - Macromolecular Chemistry Impact factor: 3.088, year: 2014

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

    OpenAIRE

    Smith, R.L.

    1984-01-01

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

  7. α-Regioselective Barbier Reaction of Carbonyl Compounds and Allyl Halides Mediated by Praseodymium.

    Science.gov (United States)

    Wu, San; Li, Ying; Zhang, Songlin

    2016-09-01

    The first utility of praseodymium as a mediating metal in the Barbier reaction of carbonyl compounds with allyl halides was reported in this paper. In contrast to the traditional metal-mediated or catalyzed Barbier reactions, exclusive α-adducts were obtained in this one-pot reaction with a broad scope of substrates and feasible reaction conditions. PMID:27490708

  8. Catalytic asymmetric allylation of aliphatic aldehydes by chiral bipyridine N,N'-dioxides

    Czech Academy of Sciences Publication Activity Database

    Hrdina, R.; Boyd, T.; Valterová, Irena; Hodačová, Jana; Kotora, Martin

    -, č. 20 (2008), s. 3141-3144. ISSN 0936-5214 Grant ostatní: GA MŠk(CZ) LC06070 Institutional research plan: CEZ:AV0Z40550506 Keywords : allylations * aldehydes * Lewis base * asymmetric catalysis * solvent effect Subject RIV: CC - Organic Chemistry Impact factor: 2.659, year: 2008

  9. Synthesis of telechelic vinyl/allyl functional siloxane copolymers with structural control

    DEFF Research Database (Denmark)

    Madsen, Frederikke Bahrt; Javakhishvili, Irakli; Jensen, Rasmus Egekjær;

    2014-01-01

    Multifunctional siloxane copolymers with terminal vinyl or allyl functional groups are synthesised through the borane-catalysed polycondensation of hydrosilanes and alkoxysilanes. Copolymers of varying mole- cular weights ( M ̄ w =13200 – 70 300 g mol − 1 ), spatially well-distributed functional ...

  10. Allylic and benzylic sp3 C-H oxidation in water.

    Science.gov (United States)

    Ang, Wei Jie; Lam, Yulin

    2015-01-28

    A copper-catalyzed method for the oxidation of allylic and benzylic sp(3) C-H by aqueous tert-butyl hydroperoxide (T-Hydro) in water using a recyclable fluorous ligand has been developed. The reaction procedure is tolerant to additional functional groups and the fluorous ligand could be reused with little loss of catalytic activity. PMID:25412371

  11. Polystyrene-supported Selenides and Selenoxide:Versatile Routes to Synthesize Allylic Alcohols

    Institute of Scientific and Technical Information of China (English)

    Wei Ming XU; You Chu ZHANG; Xian HUANG

    2003-01-01

    Several polystyrene-supported selenides and selenoxide have been prepared firstly. These novel reagents were treated with LDA to produce selenium stabilized carbanions, which reacted with aldehydes and alkyl halides, followed by selenoxide syn-elimination and [2,3] sigmatropic rearrangement respectively to give Z-allylic alcohols stereoselectively.

  12. In(OTf)3 catalyzed allylation reaction of imines with tetraallyltin

    Institute of Scientific and Technical Information of China (English)

    Xiao Ning Wei; Ling Yan Liu; Bing Wang; Wei Xing Chang; Jing Li

    2009-01-01

    In the presence of catalytic amount of In(OTf)3 (10 mol%), a series of aldimines reacted with tetraallyltin in a 2:1 molar ratio to afford the corresponding homoallylic amines in good yields. The good atom efficiency was achieved under mild reaction conditions and a new protocol (allyl)4Sn/In(OTf)3 for simple imines was developed.

  13. Syntheses of a Flobufen Metabolite and Dapoxetine Based on Enantioselective Allylation of Aromatic Aldehydes

    Czech Academy of Sciences Publication Activity Database

    Hessler, F.; Korotvička, A.; Nečas, D.; Valterová, Irena; Kotora, M.

    2014-01-01

    Roč. 2014, č. 12 (2014), s. 2543-2548. ISSN 1434-193X Grant ostatní: GA ČR(CZ) GAP207/11/0587 Institutional support: RVO:61388963 Keywords : synthetic methods * asymmetric catalysis * organocatalysis * allylation * aldehydes * enantioselectivity Subject RIV: CC - Organic Chemistry Impact factor: 3.065, year: 2014

  14. Organocatalytic asymmetric allylic amination of Morita–Baylis–Hillman carbonates of isatins

    Directory of Open Access Journals (Sweden)

    Hang Zhang

    2012-08-01

    Full Text Available The investigation of a Lewis base catalyzed asymmetric allylic amination of Morita–Baylis–Hillman carbonates derived from isatins afforded an electrophilic pathway to access multifunctional oxindoles bearing a C3-quaternary stereocenter, provided with good to excellent enantioselectivity (up to 94% ee and in high yields (up to 97%.

  15. Method of preparing water purification membranes. [polymerization of allyl amine as thin films in plasma discharge

    Science.gov (United States)

    Hollahan, J. R.; Wydeven, T. J., Jr. (Inventor)

    1974-01-01

    Allyl amine and chemically related compounds are polymerized as thin films in the presence of a plasma discharge. The monomer compound can be polymerized by itself or in the presence of an additive gas to promote polymerization and act as a carrier. The polymerized films thus produced show outstanding advantages when used as reverse osmosis membranes.

  16. Rationalizing Ring-Size Selectivity in Intramolecular Pd-Catalyzed Allylations of Resonance-Stabilized Carbanions

    DEFF Research Database (Denmark)

    Norrby, Per-Ola; Mader, Mary M.; Vitale, Maxime; Prestat, Guillaume; Poli, Giovanni

    2003-01-01

    Computational methods were applied to the Pd-catalyzed intramolecular allylations of resonance-stabilized carbanions obtained from amide and ketone substrates, with the aim of rationalizing the endo- vs. exo-selectivity in the cyclizations. In addition, ester substrates were prepared and subjecte...

  17. Oxidative allylic rearrangement of cycloalkenols: Formal total synthesis of enantiomerically pure trisporic acid B

    Directory of Open Access Journals (Sweden)

    Bernhard Westermann

    2011-04-01

    Full Text Available Enantiomerically highly enriched unsaturated β-ketoesters bearing a quaternary stereocenter can be utilized as building blocks for the synthesis of natural occurring terpenes, i. a., trisporic acid and its derivatives. An advanced building block has been synthesized in a short reaction sequence, which involves an oxidative allylic rearrangement initiated by pyridinium dichromate (PDC as the key step.

  18. Enantioselective copper catalyzed allylic alkylation using Grignard reagents; Applications in synthesis

    NARCIS (Netherlands)

    Zijl, Anthoni Wouter van

    2009-01-01

    Enantioselective copper catalyzed allylic alkylation is a powerful carbon-carbon bond forming reaction. In this thesis the development of a new catalyst for the use of Grignard reagents in this reaction is described. This catalyst is based on copper and the ligand Taniaphos. The high regio- and enan

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

    Science.gov (United States)

    Nazari, Behzad; Rhoades, Alicyn; Colby, Ralph

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

  20. Gold(I)-Catalyzed Intramolecular Hydroamination of N-Allylic,N′-Aryl Ureas to form Imidazolidin-2-ones

    OpenAIRE

    Li, Hao; Song, Feijie; Widenhoefer, Ross A.

    2011-01-01

    Treatment of N-allylic,N′-aryl ureas with a catalytic 1:1 mixture of di-tert-butyl-o-biphenylphoshphine gold(I) chloride and silver hexafluorophosphate (1 mol %) in chloroform at room temperature led to 5-exo hydroamination to form the corresponding imidazolidin-2-ones in excellent yield. In the case of N-allylic ureas that possessed an allylic alkyl, benzyloxymethyl, or acetoxymethyl substituent, gold(I)-catalyzed 5-exo hydroamination leads to formation of the corresponding trans-3,4-disubst...

  1. Gold(I)-Catalyzed Intramolecular Hydroamination of N-Allylic,N'-Aryl Ureas to form Imidazolidin-2-ones.

    Science.gov (United States)

    Li, Hao; Song, Feijie; Widenhoefer, Ross A

    2011-04-18

    Treatment of N-allylic,N'-aryl ureas with a catalytic 1:1 mixture of di-tert-butyl-o-biphenylphoshphine gold(I) chloride and silver hexafluorophosphate (1 mol %) in chloroform at room temperature led to 5-exo hydroamination to form the corresponding imidazolidin-2-ones in excellent yield. In the case of N-allylic ureas that possessed an allylic alkyl, benzyloxymethyl, or acetoxymethyl substituent, gold(I)-catalyzed 5-exo hydroamination leads to formation of the corresponding trans-3,4-disubstituted imidazolidin-2-ones in excellent yield with ≥50:1 diastereoselectivity. PMID:21709731

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

    Directory of Open Access Journals (Sweden)

    Atsushi Morikawa

    2016-02-01

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

  3. Atmospheric lifetimes of selected fluorinated ether compounds

    DEFF Research Database (Denmark)

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

    1998-01-01

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

  4. Unitary information ether and its possible applications

    International Nuclear Information System (INIS)

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

  5. Synthesis and characterization of monosize magnetic poly(glycidyl methacrylate) beads

    Institute of Scientific and Technical Information of China (English)

    Evrim; Banu; Alt1nta

    2007-01-01

    [1]Akg(o)l,S.,& Denizli,A.(2004).Novel metal-chelate affinity sorbents for reversible use in catalase adsorption.Journal of Molecular Catalysis B,28(1),7-14.[2]Altintas,E.B.,& Denizli,A.(2006a).Efficient removal of albumin from human serum by monosize dye-affinity beads.Journal of Chromatography B,832(2),216-223.[3]Altintas,E.B.,& Denizli,A.(2006b).Monosize poly(glycidyl methacrylate)beads for dye-affinity purification of lysozyme.International Journal of Biological Macromolecules,38(2),99-106.[4]Arica,M.Y.,Yavuz,H.,Patir,S.,& Denizli,A.(2000).Immobilization of glucoamylase onto spacer-arm attached magnetic poly(methylmethacrylate)microspheres:Characterization and application to a continuous flow reactor.Journal of Molecular Catalysis B,11(2-3),127-138.[5]Bahar,T.,& Celebi,S.S.(1998).Characterization of glucoamylase immobilized on magnetic poly(styrene) particles.Enzyme and Microbial Technology,23(5),301-304.[6]Bilkova,Z.,Slovakova,M.,Lycka,A.,Horak,D.,Lenfeld,J.,Turkova,J.,et al.(2002).Oriented immobilization of galactose oxidase to bead and magnetic bead cellulose and poly(HEMA-co-EDMA) and magnetic poly(HEMA-coEDMA) microspheres.Journal of Chromatography B,770(1-2),25-34.[7]Bohm,D.,& Pittermann,B.(2000).Magnetically stabilized fluidized beds in biochemical engineering-Investigations in hydrodynamics.Chemical Engineering and Technology,23,309-312.[8]Burns,M.A.,Kvesitadze,G.I.,& Graves,D.J.(1985).Dried calcium alginate/magnetite spheres:A new support for chromatographic separations and enzyme immobilization.Biotechnology and Bioengineering,27(2),137-145.[9]Cherty,A.S.,Gabis,D.H.,& Burns,M.A.(1991).Overcoming support limitations in magnetically stabilized fluidized bed separators.Powder Technology,64(1-2),165-174.[10]Cocker,T.M.,Fee,C.J.,& Evans,R.A.(1997).Preparation of magnetically susceptible polyacrylamide/magnetite beads for use in magnetically stabilized fluidized bed chromatography.Biotechnology and Bioengineering,53(1),79-87.[11]Denizli

  6. Stereochemistry of ring-opening/cross metathesis reactions of exo- and endo-7-oxabicyclo[2.2.1]hept-5-ene-2-carbonitriles with allyl alcohol and allyl acetate

    Directory of Open Access Journals (Sweden)

    Piotr Wałejko

    2015-10-01

    Full Text Available The ROCM reactions of exo- and endo-2-cyano-7-oxanorbornenes with allyl alcohol or allyl acetate promoted by different ruthenium alkylidene catalysts were studied. The stereochemical outcome of the reactions was established. The issues concerning chemo- (ROCM vs ROMP, regio- (1-2- vs 1-3-product formation, and stereo- (E/Z isomerism selectivity of reactions under various conditions are discussed. Surprisingly good yields of the ROCM products were obtained under neat conditions.

  7. New CO2 adsorbent containing aminated poly(glycidyl methacrylate) grafted onto irradiated PE-PP nonwoven sheet

    International Nuclear Information System (INIS)

    A new CO2 adsorbent containing triethylamine (TEA) was prepared by radiation induced grafting of glycidyl methacrylate (GMA) onto polyethylene coated polypropylene (PE-PP) non-woven sheet followed by amination reaction. The degree of grafting (DOG%) was controlled by variation of monomer concentration and absorbed dose. The incorporation of aminated poly(GMA) was investigated by Fourier transform infrared (FTIR) and scanning electron microscope (SEM). The adsorbent with DOG of 350% and amination yield of 60% exhibited CO2 adsorption capacity of 4.52 mol/kg at ambient temperature and pressure. - Highlights: • Preparation of a new aminated fibrous adsorbent for CO2 capturing. • Grafting of GMA onto PP-PE nonwoven sheet followed by amination. • Dependence of degree of grafting on monomer concentration and absorbed dose. • FTIR and SEM evidences of grafting and amination. • CO2 adsorbent with high adsorption capacity at ambient temperature and pressure

  8. Rapid Estimation of Enantioselectivity in Lipase-catalyzed Resolution of Glycidyl Butyrate Using pH Indicator

    Institute of Scientific and Technical Information of China (English)

    WANG Ping; WANG Lei; WANG Li-cheng; LI Chun-yuan; WANG Ren; MIAO Qing-hua; YANG Ming; WANG Zhi

    2009-01-01

    A simple method for rapid estimation of the enantioselectivity of lipase in resolution of chiral esters is described. The enantioselectivity of lipase can be estimated rapidly through comparing the dif-ference of hydrolysis rates for the racemic ester and its slow reacting enantiomer under the same condition because the difference mainly depends on the enantioselective ratio(E values). The higher the enantiose-lectivity of enzyme, the larger the difference of hydrolysis rate. The bromothymol blue(BTB) can be used as pH indicator for microplate reader to monitor the formation of acid in lipase-catalyzed hydrolysis ofesters. This method has been successfully used to rapidly estimate the enantioselectivity of several lipases in the resolution of glycidyl butyrate.

  9. Characterization of amyloglucosidase immobilized on the copolymer of ethylene glycol dimethacrylate and glycidyl methacrylate in simulated industrial conditions

    Directory of Open Access Journals (Sweden)

    Milosavić Nenad B.

    2004-01-01

    Full Text Available The application of amyloglucosidase immobilized on the macroporous co-polymer of ethylene glycol dimethacrylate and glycidyl methacrylate (poly (GMA-co-EGDMA in an enzyme reactor was shown. The higher thermostability of immobilized glucoamylases than the soluble one was demonstrated. Immobilized amyloglucosidase obtained by the periodate method shows two times higher thermo stability than the soluble form. Glucoamylases immobilized on poly (GMA-co-EGDMA have good mechanical and chemical features in the reactor and when applied in a continuous flow reactor for 28 days no changes are observed. In this period periodate immobilized amyloglucosidase shows no decrease in activity. It showed potential for the continuous production of glucose from starch over a prolonged period of time.

  10. Vibronic spectra of the allyl radical at 6-8 eV with resonance-enhanced multiphoton ionization technique

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The allyl radical was produced in molecular beam by pyrolysis of allyl iodide. The vibronic spectra from ground state to six new electronic states of the allyl radical at 6-8 eV, p?3dxz , p?3dxy, and p?ns (n=4, 6, 7, 8) were observed firstly with the aid of time-of-flight mass spectroscopy and resonance-enhanced multiphoton ionization technique. Vibrational progression of n7 (C3 bend) with gross spacing of about 430 cm-1 was observed in ns Rydberg states. The adiabatic ionization potential of the allyl radical was obtained to be (65641 ± 20) cm-1 ((8.138 ± 0.002) eV) by fitting the term values of ns (n=4,6,7,8) Rydberg states with Rydberg formula.

  11. Preparation and characterization of poly(glycidyl methacrylate) grafted from magnesium hydroxide particles via SI-ATRP

    International Nuclear Information System (INIS)

    In order to improve the compatibility of magnesium hydroxide particles [Mg(OH)2] and polymer matrix, poly(glycidyl methacrylate) (PGMA) grafted from magnesium hydroxide particles were synthesized via surface-initiated atom transfer radical polymerization (SI-ATRP). In this work, two approaches for the immobilization of ATRP initiator on the magnesium hydroxide particles surface were compared and selected. The density of initiator was significantly increased by the method of introducing more hydroxyl groups via ATRP of 2-hydroxyethyl methacrylate (HEMA) on the surface. The percentage of bromine atom for the initiator-functionalized magnesium hydroxide particles [Mg(OH)2-g-PHEMA-Br] reached to 1.75%, compared to 0.48% for Mg(OH)2-Br determined by XPS analysis. The surface-initiated ATRP of glycidyl methacrylate (GMA) can be conducted in a controlled manner, as revealed by the linear kinetic plot, linear increase of number average molecular weight (Mn) with monomer conversions, and the relatively narrow molecular weight distributions (Mw/Mn ∼ 1.4) of PGMA chains. The percentage of grafting PG (%) and the thickness of the grafted polymer layer increased with the increasing of polymerization time and reached to 116.6% and 197.6 nm after 300 min respectively. As for the polymerization with different initial monomer concentration, the number average molecular weights (Mn) and weight average molecular weights (Mw) of PGMA increased with the increasing of initial monomer concentration. TGA indicated that the initial decomposition temperature of Mg(OH)2-g-PHEMA-PGMA composite particles (253 °C) was much lower than that of unmodified magnesium hydroxide particles (337 °C).

  12. Preparation and characterization of poly(glycidyl methacrylate) grafted from magnesium hydroxide particles via SI-ATRP

    Science.gov (United States)

    Liu, Jianhui; Feng, Na; Chang, Suqin; Kang, Hongliang

    2012-06-01

    In order to improve the compatibility of magnesium hydroxide particles [Mg(OH)2] and polymer matrix, poly(glycidyl methacrylate) (PGMA) grafted from magnesium hydroxide particles were synthesized via surface-initiated atom transfer radical polymerization (SI-ATRP). In this work, two approaches for the immobilization of ATRP initiator on the magnesium hydroxide particles surface were compared and selected. The density of initiator was significantly increased by the method of introducing more hydroxyl groups via ATRP of 2-hydroxyethyl methacrylate (HEMA) on the surface. The percentage of bromine atom for the initiator-functionalized magnesium hydroxide particles [Mg(OH)2-g-PHEMA-Br] reached to 1.75%, compared to 0.48% for Mg(OH)2-Br determined by XPS analysis. The surface-initiated ATRP of glycidyl methacrylate (GMA) can be conducted in a controlled manner, as revealed by the linear kinetic plot, linear increase of number average molecular weight (Mn) with monomer conversions, and the relatively narrow molecular weight distributions (Mw/Mn ˜ 1.4) of PGMA chains. The percentage of grafting PG (%) and the thickness of the grafted polymer layer increased with the increasing of polymerization time and reached to 116.6% and 197.6 nm after 300 min respectively. As for the polymerization with different initial monomer concentration, the number average molecular weights (Mn) and weight average molecular weights (Mw) of PGMA increased with the increasing of initial monomer concentration. TGA indicated that the initial decomposition temperature of Mg(OH)2-g-PHEMA-PGMA composite particles (253 °C) was much lower than that of unmodified magnesium hydroxide particles (337 °C).

  13. Preparation and characterization of poly(glycidyl methacrylate) grafted from magnesium hydroxide particles via SI-ATRP

    Energy Technology Data Exchange (ETDEWEB)

    Liu Jianhui [School of Textile and Materials Engineering, Dalian Polytechnic University, Dalian 116034 (China); Feng Na, E-mail: fengna12@163.com [School of Textile and Materials Engineering, Dalian Polytechnic University, Dalian 116034 (China); Chang Suqin [China Leather and Footwear Industry Research Institute, Beijing 100015 (China); Kang Hongliang [State Key Laboratory of Polymer Physics and Chemistry, Joint Laboratory of Polymer Science and Material, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 (China)

    2012-06-01

    In order to improve the compatibility of magnesium hydroxide particles [Mg(OH){sub 2}] and polymer matrix, poly(glycidyl methacrylate) (PGMA) grafted from magnesium hydroxide particles were synthesized via surface-initiated atom transfer radical polymerization (SI-ATRP). In this work, two approaches for the immobilization of ATRP initiator on the magnesium hydroxide particles surface were compared and selected. The density of initiator was significantly increased by the method of introducing more hydroxyl groups via ATRP of 2-hydroxyethyl methacrylate (HEMA) on the surface. The percentage of bromine atom for the initiator-functionalized magnesium hydroxide particles [Mg(OH){sub 2}-g-PHEMA-Br] reached to 1.75%, compared to 0.48% for Mg(OH){sub 2}-Br determined by XPS analysis. The surface-initiated ATRP of glycidyl methacrylate (GMA) can be conducted in a controlled manner, as revealed by the linear kinetic plot, linear increase of number average molecular weight (M{sub n}) with monomer conversions, and the relatively narrow molecular weight distributions (M{sub w}/M{sub n} {approx} 1.4) of PGMA chains. The percentage of grafting PG (%) and the thickness of the grafted polymer layer increased with the increasing of polymerization time and reached to 116.6% and 197.6 nm after 300 min respectively. As for the polymerization with different initial monomer concentration, the number average molecular weights (M{sub n}) and weight average molecular weights (M{sub w}) of PGMA increased with the increasing of initial monomer concentration. TGA indicated that the initial decomposition temperature of Mg(OH){sub 2}-g-PHEMA-PGMA composite particles (253 Degree-Sign C) was much lower than that of unmodified magnesium hydroxide particles (337 Degree-Sign C).

  14. Confirming the existence of π-allyl-palladium intermediates during the reaction of meta photocycloadducts with palladium(ii) compounds

    OpenAIRE

    Penkett, Clive S; Brann, Paul J; Woolford, Jason A.; Kahan, Rachel J

    2013-01-01

    The transient existence of π-allyl-palladium intermediates formed by the reaction of Pd(OAc)2 and anisole-derived meta photocycloadducts has been demonstrated using NMR techniques. The intermediates tended to be short-lived and underwent rapid reductive elimination of palladium metal to form allylic acetates, however this degradation process could be delayed by changing the reaction solvent from acetonitrile to chloroform.

  15. Anti-Markovnikov Hydroalkylation of Allylic Amine Derivatives via a Palladium–Catalyzed Reductive Cross-Coupling Reaction

    OpenAIRE

    DeLuca, Ryan J.; Sigman, Matthew S.

    2011-01-01

    A palladium-catalyzed hydroalkylation reaction of allylic amine derivatives by alkylzinc reagents is reported. This reductive cross-coupling yields anti-Markovnikov products using a variety of allylic amine protecting groups. Preliminary mechanistic studies suggest that a reversible β-hydride elimination/hydride insertion process furnishes the primary Pd-alkyl intermediate, which then undergoes transmetallation followed by reductive elimination to form a new sp3-sp3 carbon-carbon bond.

  16. Enantioselective Allylic C-H Oxidation of Terminal Olefins to Isochromans by Palladium(II)/Chiral Sulfoxide Catalysis.

    Science.gov (United States)

    Ammann, Stephen E; Liu, Wei; White, M Christina

    2016-08-01

    The enantioselective synthesis of isochroman motifs has been accomplished by palladium(II)-catalyzed allylic C-H oxidation from terminal olefin precursors. Critical to the success of this goal was the development and utilization of a novel chiral aryl sulfoxide-oxazoline (ArSOX) ligand. The allylic C-H oxidation reaction proceeds with the broadest scope and highest levels of asymmetric induction reported to date (avg. 92 % ee, 13 examples with greater than 90 % ee). PMID:27376625

  17. Synthetic Studies on Tricyclic Diterpenoids: Direct Allylic Amination Reaction of Isopimaric Acid Derivatives.

    Science.gov (United States)

    Timoshenko, Mariya A; Kharitonov, Yurii V; Shakirov, Makhmut M; Bagryanskaya, Irina Yu; Shults, Elvira E

    2016-02-01

    A selective synthesis of 7- or 14-nitrogen containing tricyclic diterpenoids was completed according to a strategy in which the key step was the catalyzed direct allylic amination of methyl 14α-hydroxy-15,16-dihydroisopimarate with a wide variety of nitrogenated nucleophiles. It was revealed that the selectivity of the reaction depends on the nature of nucleophile. The catalyzed reaction of the mentioned diterpenoid allylic alcohol with 3-nitroaniline, 3-(trifluoromethyl)aniline, and 4-(trifluoromethyl)aniline yield the subsequent 7α-, 7β- and 14αnitrogen-containing diterpenoids. The reaction with 2-nitroaniline, 4-nitro-2-chloroaniline, 4-methoxy-2-nitroaniline, phenylsulfamide, or tert-butyl carbamate proceeds with the formation of 7α-nitrogen-substituted diterpenoids as the main products. PMID:27308214

  18. Crystal structure of (E-3-allyl-2-sulfanylidene-5-[(thiophen-2-ylmethylidene]thiazolidin-4-one

    Directory of Open Access Journals (Sweden)

    Rahhal El Ajlaoui

    2015-06-01

    Full Text Available Molecules of the title compound, C11H9NOS3, are built up by one thiophene and one 2-thioxathiazolidin-4-one ring which are connected by a methylene bridge. In addition, there is an allyl substituent attached to nitrogen. The two rings are almost coplanar, making a dihedral angle between them of 0.76 (11°. The allyl group is oriented perpendicular to the mean plane through both ring systems. The crystal structure exhibits inversion dimers in which molecules are linked by pairs of C—H...O hydrogen bonds. Additional π–π interactions between neighboring thiophene and 2-thioxathiazolidin-4-one rings [intercentroid distance = 3.694 (2 Å] lead to the formation of a three-dimensional network.

  19. Rheology and viscosity scaling of gelatin/1-allyl-3-methylimidazolium chloride solution

    Science.gov (United States)

    Qiao, Congde; Li, Tianduo; Zhang, Ling; Yang, Xiaodeng; Xu, Jing

    2014-05-01

    Gelatin/1-allyl-3-methylimidazolium chloride solutions are prepared by using the ionic liquid 1-allyl-3-methylimidazolium chloride as solvent. The rheological properties of the gelatin solutions have been investigated by steady shear and oscillatory shear measurements. In the steady shear measurements, the gelatin solutions with high concentration show a shear-thinning flow behavior at high shear rates, while another shear thinning region can be found in the dilute gelatin solutions at low shear rates. The overlap concentration of gelatin in [amim]Cl is 1.0 wt% and the entanglement concentration is a factor of 4 larger (4.0 wt%). The high intrinsic viscosity (295 mL/g) indicates that the gelatin chains dispersed freely in the ionic liquid and no aggregation phenomenon occurs in dilute gelatin solution. The frequency dependences of modulus changed obviously with an increase in gelatin concentration. The empirical time-temperature superposition principle holds true at the experimental temperatures.

  20. Tether-directed synthesis of highly substituted oxasilacycles via an intramolecular allylation employing allylsilanes

    Directory of Open Access Journals (Sweden)

    Cox Liam R

    2007-02-01

    Full Text Available Abstract Background Using a silyl tether to unite an aldehyde electrophile and allylsilane nucleophile into a single molecule allows a subsequent Lewis-acid-mediated allylation to proceed in an intramolecular sense and therefore receive all the benefits associated with such processes. However, with the ability to cleave the tether post allylation, a product that is the result of a net intermolecular reaction can be obtained. In the present study, four diastereoisomeric β-silyloxy-α-methyl aldehydes, which contain an allylsilane tethered through the β-carbinol centre, have been prepared, in order to probe how the relative configuration of the two stereogenic centres affects the efficiency and selectivity of the intramolecular allylation. Results Syn-aldehydes, syn-4a and syn-4b, both react poorly, affording all four possible diastereoisomeric oxasilacycle products. In contrast, the anti aldehydes anti-4a and anti-4b react analogously to substrates that lack substitution at the α-site, affording only two of the four possible allylation products. Conclusion The outcome of the reaction with anti-aldehydes is in accord with reaction proceeding through a chair-like transition state (T.S.. In these systems, the sense of 1,3-stereoinduction can be rationalised by the aldehyde electrophile adopting a pseudoaxial orientation, which will minimise dipole-dipole interactions in the T.S. The 1,4-stereoinduction in these substrates is modest and seems to be modulated by the R substituent in the starting material. In the case of the syn-substrates, cyclisation through a chair T.S. is unlikely as this would require the methyl substituent α to the reacting carbonyl group to adopt an unfavourable pseudoaxial position. It is therefore proposed that these substrates react through poorly-defined T.S.s and consequently exhibit essentially no stereoselectivity.

  1. Experimental and Kinetic Modeling Study of 2-Methyl-2-Butene: Allylic Hydrocarbon Kinetics.

    Science.gov (United States)

    Westbrook, Charles K; Pitz, William J; Mehl, Marco; Glaude, Pierre-Alexandre; Herbinet, Olivier; Bax, Sarah; Battin-Leclerc, Frederique; Mathieu, Olivier; Petersen, Eric L; Bugler, John; Curran, Henry J

    2015-07-16

    Two experimental studies have been carried out on the oxidation of 2-methyl-2-butene, one measuring ignition delay times behind reflected shock waves in a stainless steel shock tube, and the other measuring fuel, intermediate, and product species mole fractions in a jet-stirred reactor (JSR). The shock tube ignition experiments were carried out at three different pressures, approximately 1.7, 11.2, and 31 atm, and at each pressure, fuel-lean (ϕ = 0.5), stoichiometric (ϕ = 1.0), and fuel-rich (ϕ = 2.0) mixtures were examined, with each fuel/oxygen mixture diluted in 99% Ar, for initial postshock temperatures between 1330 and 1730 K. The JSR experiments were performed at nearly atmospheric pressure (800 Torr), with stoichiometric fuel/oxygen mixtures with 0.01 mole fraction of 2M2B fuel, a residence time in the reactor of 1.5 s, and mole fractions of 36 different chemical species were measured over a temperature range from 600 to 1150 K. These JSR experiments represent the first such study reporting detailed species measurements for an unsaturated, branched hydrocarbon fuel larger than iso-butene. A detailed chemical kinetic reaction mechanism was developed to study the important reaction pathways in these experiments, with particular attention on the role played by allylic C-H bonds and allylic pentenyl radicals. The results show that, at high temperatures, this olefinic fuel reacts rapidly, similar to related alkane fuels, but the pronounced thermal stability of the allylic pentenyl species inhibits low temperature reactivity, so 2M2B does not produce "cool flames" or negative temperature coefficient behavior. The connections between olefin hydrocarbon fuels, resulting allylic fuel radicals, the resulting lack of low-temperature reactivity, and the gasoline engine concept of octane sensitivity are discussed. PMID:25822578

  2. Allyl isothiocyanate induced stress response in Caenorhabditis elegans

    OpenAIRE

    Saini AkalRachna K; Tyler Robert T; Shim Youn; Reaney Martin JT

    2011-01-01

    Abstract Background Allyl isothiocyanate (AITC) from mustard is cytotoxic; however the mechanism of its toxicity is unknown. We examined the effects of AITC on heat shock protein (HSP) 70 expression in Caenorhabditis elegans. We also examined factors affecting the production of AITC from its precursor, sinigrin, a glucosinolate, in ground Brassica juncea cv. Vulcan seed as mustard has some potential as a biopesticide. Findings An assay to determine the concentration of AITC in ground mustard ...

  3. Iron(III) chloride catalyzed glycosylation of peracylated sugars with allyl/alkynyl alcohols

    Energy Technology Data Exchange (ETDEWEB)

    Narayanaperumal, Senthil; Silva, Rodrigo Cesar da; Monteiro, Julia L.; Correa, Arlene G.; Paixao, Marcio W., E-mail: mwpaixao@ufscar.br [Universidade Federal de Sao Carlos (UFSCAR), SP (Brazil). Dept. de Quimica

    2012-11-15

    In this work, the use of ferric chloride as an efficient catalyst in glycosylation reactions of sugars in the presence of allyl and alkynyl alcohols is described. The corresponding glycosides were obtained with moderate to good yields. This new procedure presented greater selectivity when compared to classic methods found in the literature. Principal features of this simple method include non-hazardous reaction conditions, low-catalyst loading, good yields and high anomeric selectivity (author)

  4. Lewis base catalyzed enantioselective allylic hydroxylation of Morita-Baylis-Hillman carbonates with water

    KAUST Repository

    Zhu, Bo

    2011-08-19

    A Lewis base catalyzed allylic hydroxylation of Morita-Baylis-Hillman (MBH) carbonates has been developed. Various chiral MBH alcohols can be synthesized in high yields (up to 99%) and excellent enantioselectivities (up to 94% ee). This is the first report using water as a nucleophile in asymmetric organocatalysis. The nucleophilic role of water has been verified using 18O-labeling experiments. © 2011 American Chemical Society.

  5. On the key role of water in the allylic activation catalysed by Pd (II) bisphosphinite complexes

    Indian Academy of Sciences (India)

    Rakesh Kumar Sharma; Ashoka G Samuelson

    2006-11-01

    Palladium and platinum complexes of bisphosphinites and bisphosphines derived from mandelic acid have been prepared and characterized. Their ability to catalyze allylation of imines with allyltributylstannane has been studied. Bisphophinite complexes of Pd (II) are shown to be ideal and they work best in the presence of one equivalent of water. The near neutral conditions employed make the catalysts suitable for a wide variety of substrates.

  6. Iron(III) chloride catalyzed glycosylation of peracylated sugars with allyl/alkynyl alcohols

    International Nuclear Information System (INIS)

    In this work, the use of ferric chloride as an efficient catalyst in glycosylation reactions of sugars in the presence of allyl and alkynyl alcohols is described. The corresponding glycosides were obtained with moderate to good yields. This new procedure presented greater selectivity when compared to classic methods found in the literature. Principal features of this simple method include non-hazardous reaction conditions, low-catalyst loading, good yields and high anomeric selectivity (author)

  7. Rhodium-catalysed asymmetric allylic arylation of racemic halides with arylboronic acids

    Science.gov (United States)

    Sidera, Mireia; Fletcher, Stephen P.

    2015-11-01

    Csp2-Csp2 cross-coupling reactions between arylboronic acid and aryl halides are widely used in both academia and industry and are strategically important in the development of new agrochemicals and pharmaceuticals. Csp2-Csp3 cross-coupling reactions have been developed, but enantioselective variations are rare and simply retaining the stereochemistry is a problem. Here we report a highly enantioselective Csp2-Csp3 bond-forming method that couples arylboronic acids to racemic allyl chlorides. Both enantiomers of a cyclic chloride are converted into a single enantiomer of product via a dynamic kinetic asymmetric transformation. This Rh-catalysed method uses readily available and inexpensive building blocks and is mild and broadly applicable. For electron-deficient, electron-rich or ortho-substituted boronic acids better results are obtained with racemic allyl bromides. Oxygen substitution in the allyl halide is tolerated and the products can be functionalized to provide diverse building blocks. The approach fills a significant gap in the methods for catalytic asymmetric synthesis.

  8. The soft X-ray absorption spectrum of the allyl free radical.

    Science.gov (United States)

    Alagia, M; Bodo, E; Decleva, P; Falcinelli, S; Ponzi, A; Richter, R; Stranges, S

    2013-01-28

    The first experimental study of the X-ray absorption spectrum (XAS) of the allyl free radical, CH(2)CHCH(2), is reported. A supersonic He seeded beam of hyperthermal allyl radicals was crossed by a high resolution synchrotron radiation (SR) in the focus of a 3D ion momentum imaging time-of-flight (TOF) spectrometer to investigate the soft X-ray absorption and fragmentation processes. The XAS, recorded as Total-Ion-Yield (TIY), is dominated by C1s electron excitations from either the central carbon atom, C(C), or the two terminal carbon atoms, C(T), to the frontier orbitals, the semi-occupied-molecular-orbital (SOMO) and the lowest-unoccupied-molecular-orbital (LUMO). All of the intense features in the XAS could only be assigned with the aid of ab initio spectral simulation at the Multi-Configuration Self-Consistent-Field (MCSCF) level of theory, this level being required because of the multi-reference nature of the core-excited state wavefunctions of the open shell molecule. The ionization energies (IEs) of the singlet and triplet states of the C1s ionized allyl radical (XPS) were also calculated at the MCSCF level. PMID:23232557

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

    Science.gov (United States)

    McPeak, Jennifer Lynne

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

  10. Preparation of Novel Poly(hydroxyethyl methacrylate-co-glycidyl methacrylate-Grafted Core-Shell Magnetic Chitosan Microspheres and Immobilization of Lactase

    Directory of Open Access Journals (Sweden)

    Wendy Katiyo

    2013-06-01

    Full Text Available Poly(hydroxyethyl methacrylate-co-glycidyl methacrylate-grafted magnetic chitosan microspheres (HG-MCM were prepared using reversed-phase suspension polymerization method. The HG-MCM presented a core-shell structure and regular spherical shape with poly(hydroxyethyl methacrylate-co-glycidyl methacrylate grafted onto the chitosan layer coating the Fe3O4 cores. The average diameter of the magnetic microspheres was 10.67 μm, within a narrow size distribution of 6.6–17.4 μm. The saturation magnetization and retentivity of the magnetic microspheres were 7.0033 emu/g and 0.6273 emu/g, respectively. The application of HG-MCM in immobilization of lactase showed that the immobilized enzyme presented higher storage, pH and thermal stability compared to the free enzyme. This indicates that HG-MCM have potential applications in bio-macromolecule immobilization.

  11. On the Nature of the Intermediates and the Role of Chloride Ions in Pd-Catalyzed Allylic Alkylations: Added Insight from Density Functional Theory

    DEFF Research Database (Denmark)

    Fristrup, Peter; Ahlquist, Mårten Sten Gösta; Tanner, David Ackland;

    2008-01-01

    The reactivity of intermediates in palladium-catalyzed allylic alkylation was investigated using DFT (B3LYP) calculations including a PB-SCRF solvation model. In the presence of both phosphine and chloride ligands, the allyl intermediate is in equilibrium between a cationic eta(3)-allylPd complex...... with two phosphine ligands, the corresponding neutral complex with one phosphine and one chloride ligand, and a neutral eta(1)-allylPd complex with one chloride and two phosphine ligands. The eta(1)-complex is unreactive toward nucleophiles. The cationic eta(3)-complex is the intermediate most...

  12. Facile Synthesis of Magnetic Copolymer Microspheres Based on Poly(glycidyl methacrylate-co-N-isopropylacrylamide)/Fe3O4 by Suspension Photopolymerization

    OpenAIRE

    Siti Zulaikha Mazlan; Faszly Rahim; Sharina Abu Hanifah

    2014-01-01

    Magnetic copolymer based on poly(glycidyl methacrylate-co-N-isopropylacrylamide) microspheres was prepared by 2,2-dimethoxy-2-phenylacetophenone- (DMPP-) photo initiated and poly(vinyl alcohol)- (PVA-) stabilized single step suspension photopolymerization. The effect of chemical interaction, morphology, and thermal properties by adding 0.1% w/v Fe3O4 in the copolymer was investigated. Infrared analysis (FTIR) showed that (C=C) band disappeared after copolymerization, indicating that the magne...

  13. PEG-modified macroporous poly(glycidyl methacrylate) and poly(2-hydroxyethyl methacrylate) microspheres to reduce non-specific protein adsorption

    Czech Academy of Sciences Publication Activity Database

    Hlídková, Helena; Horák, Daniel; Proks, Vladimír; Kučerová, Z.; Pekárek, Michal; Kučka, Jan

    2013-01-01

    Roč. 13, č. 4 (2013), s. 503-511. ISSN 1616-5187 R&D Projects: GA ČR GCP207/12/J013; GA ČR GAP206/12/0381; GA MŠk 7E12053 EU Projects: European Commission(XE) 246513 - NADINE Institutional support: RVO:61389013 Keywords : coatings * glycidyl methacrylate * 2-hydroxyethyl methacrylate Subject RIV: CD - Macromolecular Chemistry Impact factor: 3.650, year: 2013

  14. Activity relationships for aromatic crown ethers

    CERN Document Server

    Wilson, M J

    1998-01-01

    This thesis involves an investigation of aromatic crown ethers and a study of their binding constants for alkali metals. The study was motivated by the current needs of the semiconductor industry to improve the scavenging of mobile ions from fabricated circuits. A number of aromatic crown ethers have been sulphonated in an attempt to improve their water solubility and cation binding activity. These materials have been extensively studied and their binding activity determined. In collaboration with a molecular modelling study, the effect of ionisable sulphonate groups on the macrocycles' behaviour has been investigated. The broader issue of the effect of substituents in aromatic crown ethers has also been studied with the preparation of a wide range of substituted crown ethers. The cation binding activity of these materials has been found to bear a simple relationship to the electron withdrawing nature of the aromatic substituents. This relationship can be accurately monitored using electronic charge densities...

  15. Exogenous ether lipids predominantly target mitochondria

    DEFF Research Database (Denmark)

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

    2012-01-01

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

  16. Bulk and interfacial properties of cellulose ethers

    OpenAIRE

    Bodvik, Rasmus

    2012-01-01

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

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

    NARCIS (Netherlands)

    Koziara, B.T.

    2015-01-01

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

  18. Lectin-functionalized poly(glycidyl methacrylate)-block-poly(vinyldimethyl azlactone) surface supports for high avidity microbial capture

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Ryan R [ORNL; Hinestrosa Salazar, Juan P [ORNL; Shubert, Katherine R [ORNL; Morrell, Jennifer L. [University of Tennessee, Knoxville (UTK); Pelletier, Dale A [ORNL; Messman, Jamie M [ORNL; Kilbey, II, S Michael [ORNL; Lokitz, Bradley S [ORNL; Retterer, Scott T [ORNL

    2013-01-01

    Microbial exopolysaccharides (EPS) play a critical and dynamic role in shaping the interactions between microbial community members and their local environment. The capture of targeted microbes using surface immobilized lectins that recognize specific extracellular oligosaccharide moieties offers a non-destructive method for functional characterization based on EPS content. In this report, we evaluate the use of the block co-polymer, poly(glycidyl methacrylate)-block-4,4-dimethyl-2-vinylazlactone (PGMA-b-PVDMA), as a surface support for lectin-specific microbial capture. Arrays of circular polymer supports ten micron in diameter were generated on silicon substrates to provide discrete, covalent coupling sites for Triticum vulgare and Lens culinaris lectins. These supports promoted microbe adhesion and colony formation in a lectin-specific manner. Silicon posts with similar topography containing only physisorbed lectins showed significantly less activity. These results demonstrate that micropatterned PGMA-b-PVDMA supports provide a unique platform for microbial capture and screening based on EPS content by combining high avidity lectin surfaces with three-dimensional topography.

  19. Manipulating Interfaces through Surface Confinement of Poly(glycidyl methacrylate)-block-poly(vinyldimethylazlactone), a Dually Reactive Block Copolymer

    International Nuclear Information System (INIS)

    The assembly of dually reactive, well-defined diblock copolymers incorporating the chemoselective/functional monomer, 4,4-dimethyl-2-vinylazlactone (VDMA) and the surface-reactive monomer glycidyl methacrylate (GMA) is examined to understand how competition between surface attachment and microphase segregation influences interfacial structure. Reaction of the PGMA block with surface hydroxyl groups not only anchors the copolymer to the surface, but limits chain mobility, creating brush-like structures comprising PVDMA blocks, which contain reactive azlactone groups. The block copolymers are spin coated at various solution concentrations and annealed at elevated temperature to optimize film deposition to achieve a molecularly uniform layer. The thickness and structure of the polymer thin films are investigated by ellipsometry, infrared spectroscopy, and neutron reflectometry. The results show that deposition of PGMA-b-PVDMA provides a useful route to control film thickness while preserving azlactone groups that can be further modified with biotin-poly(ethylene glycol)amine to generate designer surfaces. The method described herein offers guidance for creating highly functional surfaces, films, or coatings through the use of dually reactive block copolymers and postpolymerization modification.

  20. Poly(glycidyl methacrylate) beads embedded cryogels for pseudo-specific affinity depletion of albumin and immunoglobulin G

    International Nuclear Information System (INIS)

    Depletion of high abundant proteins like albumin and immunoglobulin G (IgG) can be beneficial in the analysis of serum proteins. For this purpose, Cibacron Blue F3GA and iminodiacetic acid (IDA)-Cu2+ containing poly(glycidyl methacrylate) (PGMA) beads (1.6 μm in diameter) were embedded into the poly(hydroxyethyl methacrylate) (PHEMA) cryogel. The PGMA beads were prepared by dispersion polymerization. The PGMA beads were modified with Cibacron Blue F3GA and iminodiacetic acid (IDA)-Cu2+ for simultaneous albumin and IgG depletion, respectively. The PHEMA cryogel was synthesized by free radical polymerization in the presence of the modified PGMA beads. The PHEMA and PHEMA/PGMA composite cryogels were characterized by swelling measurements and scanning electron microscopy (SEM). Protein depletion studies were carried out in a continuous experimental set-up in a stacked column. Albumin adsorption capacity of the PGMA-Cibacron Blue F3GA beads embedded PHEMA cryogel (PHEMA/PGMA-Cibacron Blue F3GA) was 342 mg/g and IgG adsorption capacity of the PGMA-IDA-Cu2+ beads embedded PHEMA cryogel (PHEMA/PGMA-IDA-Cu2+) was 257 mg/g. The composite cryogels depleted albumin and IgG from human serum with 89.4% and 93.6% efficiency, respectively. High desorption values (over 90% for both modified cryogels) were achieved with 0.05 M phosphate buffer containing1.0 M NaCl.

  1. Selective allylic hydroxylation of acyclic terpenoids by CYP154E1 from Thermobifida fusca YX

    Directory of Open Access Journals (Sweden)

    Anna M. Bogazkaya

    2014-06-01

    Full Text Available Allylic alcohols are valuable precursors in the synthesis of pharmaceutical intermediates, agrochemicals and natural products. Regioselective oxidation of parental alkenes is a challenging task for chemical catalysts and requires several steps including protection and deprotection. Many cytochrome P450 enzymes are known to catalyse selective allylic hydroxylation under mild conditions. Here, we describe CYP154E1 from Thermobifida fusca YX that enables this type of oxidation. Several acyclic terpenoids were tested as possible substrates for CYP154E1, and the regio- and chemoselectivity of their oxidation was investigated. Using a previously established bioinformatics approach we identified position 286 in the active site of CYP154E1 which is putatively involved in substrate binding and thereby might have an effect on enzyme selectivity. To tune regio- and chemoselectivity of the enzyme three mutants at position 286 were constructed and used for substrate oxidation. All formed products were analysed with GC–MS and identified using chemically synthesised authentic samples and known compounds as references. Best regioselectivity towards geraniol and nerol was observed with the wild type enzyme mainly leading to 8-hydroxy derivatives (8-hydroxygeraniol or 8-hydroxynerol with high selectivity (100% and 96% respectively. Highest selectivities during the oxidation of geranylacetone and nerylacetone were observed with the following variants: V286F led mainly to 7-hydroxygeranylacetone (60% of the total product and V286A produced predominantly 12-hydroxynerylacetone (75% of total product. Thus, CYP154E1 and its mutants expand the tool-box for allylic hydroxylation in synthetic chemistry.

  2. Palladium/N-heterocyclic carbene catalysed regio and diastereoselective reaction of ketones with allyl reagents via inner-sphere mechanism.

    Science.gov (United States)

    Bai, Da-Chang; Yu, Fei-Le; Wang, Wan-Ying; Chen, Di; Li, Hao; Liu, Qing-Rong; Ding, Chang-Hua; Chen, Bo; Hou, Xue-Long

    2016-01-01

    The palladium-catalysed allylic substitution reaction is one of the most important reactions in transition-metal catalysis and has been well-studied in the past decades. Most of the reactions proceed through an outer-sphere mechanism, affording linear products when monosubstituted allyl reagents are used. Here, we report an efficient Palladium-catalysed protocol for reactions of β-substituted ketones with monosubstituted allyl substrates, simply by using N-heterocyclic carbene as ligand, leading to branched products with up to three contiguous stereocentres in a (syn, anti)-mode with excellent regio and diastereoselectivities. The scope of the protocol in organic synthesis has been examined preliminarily. Mechanistic studies by both experiments and density functional theory (DFT) calculations reveal that the reaction proceeds via an inner-sphere mechanism-nucleophilic attack of enolate oxygen on Palladium followed by C-C bond-forming [3,3']-reductive elimination. PMID:27283477

  3. Enhanced performance of the catalytic conversion of allyl alcohol to 3-hydroxypropionic acid using bimetallic gold catalysts.

    Science.gov (United States)

    Falletta, Ermelinda; Della Pina, Cristina; Rossi, Michele; He, Qian; Kiely, Christopher J; Hutchings, Graham J

    2011-01-01

    One of the strategic building blocks in organic synthesis is 3-hydroxypropionic acid, which is particularly important for the manufacture of high performance polymers. However, to date, despite many attempts using both biological and chemical routes, no large scale effective process for manufacturing 3-hydroxypropionic acid has been developed. One potentially useful starting point is from allyl alcohol, as this can be obtained in principle from the dehydration of glycerol, thereby presenting a bio-renewable green pathway to this important building block. The catalytic transformation of allyl alcohol to 3-hydroxypropionic acid presents interesting challenges in catalyst design, particularly with respect to the control of selectivity among the products that can be expected, as acrylic acid, acrolein and glyceric acid can also be formed. In this paper, we present a novel eco-sustainable catalytic pathway leading to 3-hydroxypropionic acid, which highlights the outstanding potential of gold-based and bimetallic catalysts in the aerobic oxidation of allyl alcohol. PMID:22455056

  4. Combined experimental and theoretical mechanistic investigation of the Barbier allylation in aqueous media

    DEFF Research Database (Denmark)

    Dam, Johan Hygum; Fristrup, Peter; Madsen, Robert

    2008-01-01

    The Barbier allylation of a series of para-substituted benzaldehydes with allylbromide in the presence of Zn, In, Sn, Sb, Bi, and Mg was investigated using competition experiments. In all cases, the slope of the Hammett plots indicated a build-up of negative charge in the selectivity-determining ...... effect of solvent described by a polarized continuum model. The calculated secondary deuterium isotope effects based on this mechanism were found to be in good agreement with experimental values, thus adding further support to this mechanistic scenario....

  5. Non-thermal plasma destruction of allyl alcohol in waste gas: kinetics and modelling

    Science.gov (United States)

    DeVisscher, A.; Dewulf, J.; Van Durme, J.; Leys, C.; Morent, R.; Van Langenhove, H.

    2008-02-01

    Non-thermal plasma treatment is a promising technique for the destruction of volatile organic compounds in waste gas. A relatively unexplored technique is the atmospheric negative dc multi-pin-to-plate glow discharge. This paper reports experimental results of allyl alcohol degradation and ozone production in this type of plasma. A new model was developed to describe these processes quantitatively. The model contains a detailed chemical degradation scheme, and describes the physics of the plasma by assuming that the fraction of electrons that takes part in chemical reactions is an exponential function of the reduced field. The model captured the experimental kinetic data to less than 2 ppm standard deviation.

  6. Thermophysical properties and reaction kinetics of γ-irradiated poly allyl diglycol carbonates nuclear track detector

    Science.gov (United States)

    Elmaghraby, Elsayed K.; Seddik, Usama

    2015-07-01

    Kinetic thermogravimetric technique was used to study the effect of gamma irradiation on the poly allyl diglycol carbonates (PADC) within the dose range from 50 to ? Gy. The approach of Coats-Redfern was used to analyze the data. Results showed that low doses around 50 Gy make the polymer slightly more resistive to heat treatment. Higher radiation doses cause severe effects in the samples accompanied by the formation of lower molecular mass species and consequent crosslinking. Results support the domination of re-polymerization and crosslinking for the γ radiation interaction PADC at dose below about ? Gy, while the situation is inverted above ? Gy in which chain secession dominates.

  7. N-(2-Allyl-4-ethoxy-2H-indazol-5-yl-4-methylbenzenesulfonamide

    Directory of Open Access Journals (Sweden)

    Hakima Chicha

    2014-05-01

    Full Text Available The indazole ring system of the title compound, C19H21N3O3S, is almost planar (r.m.s. deviation = 0.0192 Å and forms dihedral angles of 77.99 (15 and 83.9 (3° with the benzene ring and allyl group, respectively. In the crystal, centrosymmetrically related molecules are connected by pairs of N—H...O hydrogen bonds into dimers, which are further linked by C—H...O hydrogen bonds, forming columns parallel to the b axis.

  8. N-(1-Allyl-3-chloro-4-ethoxy-1H-indazol-5-yl-4-methylbenzenesulfonamide

    Directory of Open Access Journals (Sweden)

    Hakima Chicha

    2014-06-01

    Full Text Available In the title compound, C19H20ClN3O3S, the benzene ring is inclined to the indazole ring system by 51.23 (8°. In the crystal, molecules are linked by pairs of N—H...O hydrogen bonds, forming inversion dimers which stack in columns parallel to [011]. The atoms in the allyl group are disordered over two sets of sites with an occupancy ratio of 0.624 (8:0.376 (8.

  9. Allyl Isothiocyanate Increases MRP1 Function and Expression in a Human Bronchial Epithelial Cell Line

    OpenAIRE

    Dian-lei Wang; Chen-yin Wang; Yin Cao; Xian Zhang; Xiu-hua Tao; Li-li Yang; Jin-pei Chen; Shan-shan Wang; Ze-geng Li

    2014-01-01

    Multidrug resistance-associated protein 1 (MRP1), a member of the ATP-binding cassette (ABC) superfamily of transporters, plays an important role in normal lung physiology by protecting cells against oxidative stress and toxic xenobiotics. The present study investigates the effects of allyl isothiocyanate (AITC) on MRP1 mRNA and MRP1 protein expression and transporter activity in the immortalised human bronchial epithelial cell line 16HBE14o-. MRP1 mRNA and MRP1 protein expression in 16HBE14o...

  10. Non-thermal plasma destruction of allyl alcohol in waste gas: kinetics and modelling

    International Nuclear Information System (INIS)

    Non-thermal plasma treatment is a promising technique for the destruction of volatile organic compounds in waste gas. A relatively unexplored technique is the atmospheric negative dc multi-pin-to-plate glow discharge. This paper reports experimental results of allyl alcohol degradation and ozone production in this type of plasma. A new model was developed to describe these processes quantitatively. The model contains a detailed chemical degradation scheme, and describes the physics of the plasma by assuming that the fraction of electrons that takes part in chemical reactions is an exponential function of the reduced field. The model captured the experimental kinetic data to less than 2 ppm standard deviation

  11. Mild and selective vanadium-catalyzed oxidation of benzylic, allylic, and propargylic alcohols using air.

    Science.gov (United States)

    Hanson, Susan K; Wu, Ruilian; Silks, L A Pete

    2011-04-15

    Transition metal-catalyzed aerobic alcohol oxidation is an attractive method for the synthesis of carbonyl compounds, but most catalytic systems feature precious metals and require pure oxygen. The vanadium complex (HQ)(2)V(V)(O)(O(i)Pr) (2 mol %, HQ = 8-quinolinate) and NEt(3) (10 mol %) catalyze the oxidation of benzylic, allylic, and propargylic alcohols with air. The catalyst can be easily prepared under air using commercially available reagents and is effective for a wide range of primary and secondary alcohols. PMID:21434606

  12. Design of the passive personal dosimeter for miners using an allyl diglycol carbonate plastic. Phase 1

    International Nuclear Information System (INIS)

    The report summarizes the results of the feasibility study on the design and development of a passive personal dosimeter incorporating an allyl diglycol carbonate plastic (CR39) detector, for use by uranium miners. Based upon the feasibility study, a passive personal dosimeter using a capacitor-type electrostatic enhancement device has been designed. Preliminary tests indicate that the prototype could be used in the mine environment to differentiate radon and thoron daughters with a detection efficiency comparable to that of a typical active device. Further study is required, however, into the possible influence in the mine environment of local variations in charged fraction, upon the calibration of this dosimeter

  13. Direct asymmetric allylic alkenylation of N-itaconimides with Morita-Baylis-Hillman carbonates

    KAUST Repository

    Yang, Wenguo

    2012-08-03

    The asymmetric allylic alkenylation of Morita-Baylis-Hillman (MBH) carbonates with N-itaconimides as nucleophiles has been developed using a commercially available Cinchona alkaloid catalyst. A variety of multifunctional chiral α-methylene-β-maleimide esters were attained in moderate to excellent yields (up to 99%) and good to excellent enantioselectivities (up to 91% ee). The origin of the regio- and stereoselectivity was verified by DFT methods. Calculated geometries and relative energies of various transition states strongly support the observed regio- and enantioselectivity. © 2012 American Chemical Society.

  14. Lanthanum triflate triggered synthesis of tetrahydroquinazolinone derivatives of N-allyl quinolone and their biological assessment

    Directory of Open Access Journals (Sweden)

    Jardosh Hardik H.

    2012-01-01

    Full Text Available A series of 24 derivatives of tetrahydroquinazolinone has been synthesized by one-pot cyclocondensation reaction of N-allyl quinolones, cyclic β-diketones and (thiourea/N-phenylthiourea in presence of lanthanum triflate catalyst. This methodology allowed us to achieve the products in excellent yield by stirring at room temperature. All the synthesized compounds were investigated against a representative panel of pathogenic strains using broth microdilution MIC (minimum inhibitory concentration method for their in vitro antimicrobial activity. Amongst these sets of heterocyclic compounds 5h, 6b, 6h, 5f, 5l, 5n and 6g found to have admirable activity.

  15. Mechanistic Investigation of Palladium–Catalyzed Allylic C–H Activation

    DEFF Research Database (Denmark)

    Engelin, Casper Junker; Jensen, Thomas; Rodríguez-Rodríguez, Sergio;

    2013-01-01

    The mechanism for the palladium–catalyzed allylic C–H activation was investigated using a combination of experimental and theoretical methods. A Hammett study revealed a buildup of a partial negative charge in the rate-determining step, while determination of the kinetic isotope effect (KIE...... acetate acts as a base in an intramolecular fashion during the C–H activation step. The re-oxidation of palladium was found to reach a similar energy level as that of the C–H activation. Calculations of turnover frequencies (TOF) for the entire catalytic cycle for the C–H alkylation were used to acquire a...

  16. From a Sequential to a Concurrent Reaction in Aqueous Medium: Ruthenium-Catalyzed Allylic Alcohol Isomerization and Asymmetric Bioreduction.

    Science.gov (United States)

    Ríos-Lombardía, Nicolás; Vidal, Cristian; Liardo, Elisa; Morís, Francisco; García-Álvarez, Joaquín; González-Sabín, Javier

    2016-07-18

    The ruthenium-catalyzed redox isomerization of allylic alcohols was successfully coupled with the enantioselective enzymatic ketone reduction (mediated by KREDs) in a concurrent process in aqueous medium. The overall transformation, formally the asymmetric reduction of allylic alcohols, took place with excellent conversions and enantioselectivities, under mild reaction conditions, employing commercially and readily available catalytic systems, and without external coenzymes or cofactors. Optimization resulted in a multistep approach and a genuine cascade reaction where the metal catalyst and biocatalyst coexist from the beginning. PMID:27258838

  17. Iodine-Catalyzed Decarboxylative Amidation of β,γ-Unsaturated Carboxylic Acids with Chloramine Salts Leading to Allylic Amides.

    Science.gov (United States)

    Kiyokawa, Kensuke; Kojima, Takumi; Hishikawa, Yusuke; Minakata, Satoshi

    2015-10-26

    The iodine-catalyzed decarboxylative amidation of β,γ-unsaturated carboxylic acids with chloramine salts is described. This method enables the regioselective synthesis of allylic amides from various types of β,γ-unsaturated carboxylic acids containing substituents at the α- and β-positions. In the reaction, N-iodo-N-chloroamides, generated by the reaction of a chloramine salt with I2 , function as a key active species. The reaction provides an attractive alternative to existing methods for the synthesis of useful secondary allylic amine derivatives. PMID:26493878

  18. Cobalt-Catalyzed Cross-Coupling of Grignards with Allylic and Vinylic Bromides: Use of Sarcosine as a Natural Ligand.

    Science.gov (United States)

    Frlan, Rok; Sova, Matej; Gobec, Stanislav; Stavber, Gaj; Časar, Zdenko

    2015-08-01

    Sarcosine was discovered to be an excellent ligand for cobalt-catalyzed carbon-carbon cross-coupling of Grignard reagents with allylic and vinylic bromides. The Co(II)/sarcosine catalytic system is shown to perform efficiently when phenyl and benzyl Grignards are coupled with alkenyl bromides. Notably, previously unachievable Co-catalyzed coupling of allylic bromides with Grignards to linearly coupled α-products was also realized with Co(II)/sarcosine catalyst. This method was used for efficient preparation of the key intermediate in an alternative synthesis of the antihyperglycemic drug sitagliptin. PMID:26158563

  19. Injection characteristics of dimethyl ether

    Energy Technology Data Exchange (ETDEWEB)

    Glensvig, M.

    1996-09-01

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

  20. A Convenient and Efficient Procedure for Oxime Ethers

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

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

  1. Allyl thiourea as a corrosion inhibitor for cold rolled steel in H3PO4 solution

    International Nuclear Information System (INIS)

    Highlights: ► Allyl thiourea (ATU) acts as a good inhibitor for steel in 1.0 M H3PO4. ► Inhibition efficiency increases slightly with the temperature at 0.2–0.5 mM. ► The adsorption of ATU on steel surface obeys Langmuir adsorption isotherm. ► ATU behaves as a mixed-type inhibitor. - Abstract: The inhibition effect of allyl thiourea (ATU) on the corrosion of cold rolled steel (CRS) in 1.0 M H3PO4 solution at 20–50 °C was studied by weight loss, potentiodynamic polarisation, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) methods. The results show that ATU is a good inhibitor, and the maximum inhibition efficiency of 0.5 mM inhibitor is higher than 95% at all studied temperatures. The adsorption of ATU obeys Langmuir adsorption isotherm. Polarisation curves show that ATU behaves as a mixed-type inhibitor. EIS spectra exhibit one capacitive loop. The inhibition action is also evidenced by SEM.

  2. Polymerizations of beta-substituted allylic arsonium ylides with catalytic amounts of organoboron compounds

    International Nuclear Information System (INIS)

    My Ph.D. work consisted in the generalization and optimization of a new polymerization reaction involving allylic arsonium ylides and catalytic amounts of various boron compounds. Thus, various β-substituted allylic arsonium salts were produced according to synthetic strategies that depended on the nature of the functional group born by the salt. These salts were converted in situ to the corresponding arsonium ylides which were then treated with boron compounds to yield polymers. Our new method of polymerization afforded either non conjugated polyenes that are functionalized every three atoms of carbon, or statistic copolymers, depending on the nature of the group R born on the β position of the ylide. These new polymers cannot be synthesized by usual methods of polymerization. Initial molar ratios of reactants were found to give molar mass control of the synthesized polymers. This controlled polymerization allowed us to produce several bloc copolymers. All the polymers were characterized by NMR techniques, by size exclusion chromatography and, for some of them, by mass spectrometry. Investigation of their physicochemical properties will need additional experiments. (author)

  3. Further exploration of the heterocyclic diversity accessible from the allylation chemistry of indigo

    Directory of Open Access Journals (Sweden)

    Alireza Shakoori

    2015-04-01

    Full Text Available Diversity-directed synthesis based on the cascade allylation chemistry of indigo, with its embedded 2,2’-diindolic core, has resulted in rapid access to new examples of the hydroxy-8a,13-dihydroazepino[1,2-a:3,4-b']diindol-14(8H-one skeleton in up to 51% yield. Additionally a derivative of the novel bridged heterocycle 7,8-dihydro-6H-6,8a-epoxyazepino[1,2-a:3,4-b']diindol-14(13H-one was produced when the olefin of the allylic substrate was terminally disubstituted. Further optimisation also produced viable one-pot syntheses of derivatives of the spiro(indoline-2,9'-pyrido[1,2-a]indol-3-one (65% and pyrido[1,2,3-s,t]indolo[1,2-a]azepino[3,4-b]indol-17-one (72% heterocyclic systems. Ring-closing metathesis of the N,O-diallylic spiro structure and subsequent Claisen rearrangement gave rise to the new (1R,8aS,17aS-rel-1,2-dihydro-1-vinyl-8H,17H,9H-benz[2',3']pyrrolizino[1',7a':2,3]pyrido[1,2-a]indole-8,17-(2H,9H-dione heterocyclic system.

  4. Iron complexes of tetramine ligands catalyse allylic hydroxyamination via a nitroso–ene mechanism

    Science.gov (United States)

    Porter, David; Poon, Belinda M-L

    2015-01-01

    Summary Iron(II) complexes of the tetradentate amines tris(2-pyridylmethyl)amine (TPA) and N,N′-bis(2-pyridylmethyl)-N,N′-dimethylethane-1,2-diamine (BPMEN) are established catalysts of C–O bond formation, oxidising hydrocarbon substrates via hydroxylation, epoxidation and dihydroxylation pathways. Herein we report the capacity of these catalysts to promote C–N bond formation, via allylic amination of alkenes. The combination of N-Boc-hydroxylamine with either FeTPA (1 mol %) or FeBPMEN (10 mol %) converts cyclohexene to the allylic hydroxylamine (tert-butyl cyclohex-2-en-1-yl(hydroxy)carbamate) in moderate yields. Spectroscopic studies and trapping experiments suggest the reaction proceeds via a nitroso–ene mechanism, with involvement of a free N-Boc-nitroso intermediate. Asymmetric induction is not observed using the chiral tetramine ligand (+)-(2R,2′R)-1,1′-bis(2-pyridylmethyl)-2,2′-bipyrrolidine ((R,R′)-PDP). PMID:26734101

  5. Iron complexes of tetramine ligands catalyse allylic hydroxyamination via a nitroso–ene mechanism

    Directory of Open Access Journals (Sweden)

    David Porter

    2015-12-01

    Full Text Available Iron(II complexes of the tetradentate amines tris(2-pyridylmethylamine (TPA and N,N′-bis(2-pyridylmethyl-N,N′-dimethylethane-1,2-diamine (BPMEN are established catalysts of C–O bond formation, oxidising hydrocarbon substrates via hydroxylation, epoxidation and dihydroxylation pathways. Herein we report the capacity of these catalysts to promote C–N bond formation, via allylic amination of alkenes. The combination of N-Boc-hydroxylamine with either FeTPA (1 mol % or FeBPMEN (10 mol % converts cyclohexene to the allylic hydroxylamine (tert-butyl cyclohex-2-en-1-yl(hydroxycarbamate in moderate yields. Spectroscopic studies and trapping experiments suggest the reaction proceeds via a nitroso–ene mechanism, with involvement of a free N-Boc-nitroso intermediate. Asymmetric induction is not observed using the chiral tetramine ligand (+-(2R,2′R-1,1′-bis(2-pyridylmethyl-2,2′-bipyrrolidine ((R,R′-PDP.

  6. 40 CFR 721.3435 - Butoxy-substituted ether alkane.

    Science.gov (United States)

    2010-07-01

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

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

    International Nuclear Information System (INIS)

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

  8. Finkelstein Reaction in Functionalized Crown-ether Ionic Liquids

    Institute of Scientific and Technical Information of China (English)

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

    2006-01-01

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

  9. Alkyl Aryl Ether Bond Formation with PhenoFluor**

    OpenAIRE

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

    2015-01-01

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

  10. 40 CFR 721.3550 - Dipropylene glycol dimethyl ether.

    Science.gov (United States)

    2010-07-01

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

  11. 40 CFR 799.4440 - Triethylene glycol monomethyl ether.

    Science.gov (United States)

    2010-07-01

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

  12. Reproductive toxicity evaluation of the dental resin monomer bisphenol a glycidyl methacrylate (CAS 1565-94-2) in mice.

    Science.gov (United States)

    Moilanen, Lori H; Dahms, Janell K; Hoberman, Alan M

    2013-01-01

    The reproductive toxicity potential of the dental resin monomer bisphenol A glycidyl methacrylate (BisGMA; CASRN 1565-94-2) was investigated in male and female Crl: CD1(ICR) mice, 4 dosage groups, and 25 mice/sex/group. Formulations of BisGMA (0, 0.008, 0.08, or 0.8 mg/kg/d) in 0.8% ethanol in deionized water were intubated once daily beginning 28 days before cohabitation and continuing through mating (males) or through gestation day 17. The following parameters were evaluated: viability, clinical signs, body weights, estrous cyclicity, necropsy observations, organ weights, sperm concentration/motility/morphology, cesarean sectioning and litter observations, and histopathological evaluation of select tissues. No deaths or clinical signs related to BisGMA occurred. No significant changes in male and female body weights and body weight gains were recorded at any of the administered dosages of BisGMA. All mating and fertility parameters, and all litter and fetal data, were considered to be unaffected by dosages of BisGMA as high as 0.8 mg/kg/d. Gross or histopathologic tissue changes attributable to the test article were not observed. Reproductive and developmental no observed effect levels (NOAELs) for BisGMA were 0.8 mg/kg/d, the highest dose tested. Comparison of this NOAEL value to published probabilistic estimates of human BisGMA exposure from dental products suggests a margin of safety of at least 280- to nearly 2000-fold. Under the conditions of this study, BisGMA is not a reproductive toxicant. PMID:24231940

  13. Gamma radiation-induced grafting of glycidyl methacrylate to water hyacinth fibers: functionalization and metal ion uptake kinetics

    International Nuclear Information System (INIS)

    Water hyacinth fibers (WHF) were functionalized using gamma radiation-induced graft polymerization of glycidyl methacrylate (GMA) to obtain fibers with oxirane groups for chemical modification. The simultaneous grafting technique was employed wherein the WHF were irradiated in nitrogen atmosphere in the presence of GMA dissolved in water/methanol solvent. The effects of different grafting parameters to the grafting yield were evaluated. The optimal values of solvent, radiation absorbed dose, dose rate, concentration of monomer were found to be 1:3 (volume/volume) water-methanol solvent, 10 kGy, 8 kGy hour -1 dose rate and 5% (volume/volume) GMA, respectively. Using the optimum conditions, grafting yield approximately 58% was achieved. The GMA grafted WHF were subsequently modified with ethylenediamine and sodium sulfite. The resulting amine and sulfonic acid functionalized WHF, together with the grafted WHF, were characterized using Attenuated Total Reflectance-Fourier Transformed Infrared Spectroscopy (ATR-FTIR). Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDX). The sorption of Cu2+, Cr3+ and Pb2+ ions on the amine functionalized WHF was studied. The initial concentration of the metal ions and pH of the solution were found to have important effect on the adsorption of the metal ions onto the amine functionalized WHF. The kinetics of adsorption was observed to follow Lagergren first order equation. Results of ion sorption studies indicate that radiation induced grafting and subsequent chemical modification improved the ion sorption behavior of WHF. (author)

  14. A facile stereospecific synthesis of the ( sup 2 H sub 6 )-isopropyl-labelled metoprolol enantiomers from (2R)- and (2S)-glycidyl 3-nitrobenzenesulfonate

    Energy Technology Data Exchange (ETDEWEB)

    Murthy, S.S.; Nelson, W.L. (Washington Univ., Seattle, WA (USA). Dept. of Medicinal Chemistry)

    1990-12-01

    Enantiomers of metoprolol containing six deuterium atoms in the isopropyl methyl groups were prepared in two steps from the sodium salt of 4-(2-methoxyethyl)phenol (3) and the commercially available (2R)-and (2S)-glycidyl 3-nitrobenzenesulfonates ((2R)-2 and (2S)-2). The resulting (2R)- and (2S)-epoxides were opened using ({sup 2}H{sub 6})-isopropylamine. The enantiomeric excesses were 93 and 95% for the deuterated (2R)- and (2S)-enantiomers of metoprolol ((2R)-1 and (2S)-1), respectively, as determined by chiral column HPLC. (author).

  15. A facile stereospecific synthesis of the [2H6]-isopropyl-labelled metoprolol enantiomers from (2R)- and (2S)-glycidyl 3-nitrobenzenesulfonate

    International Nuclear Information System (INIS)

    Enantiomers of metoprolol containing six deuterium atoms in the isopropyl methyl groups were prepared in two steps from the sodium salt of 4-(2-methoxyethyl)phenol (3) and the commercially available (2R)-and (2S)-glycidyl 3-nitrobenzenesulfonates [(2R)-2 and (2S)-2]. The resulting (2R)- and (2S)-epoxides were opened using [2H6]-isopropylamine. The enantiomeric excesses were 93 and 95% for the deuterated (2R)- and (2S)-enantiomers of metoprolol [(2R)-1 and (2S)-1], respectively, as determined by chiral column HPLC. (author)

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

    Science.gov (United States)

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

    2016-07-01

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

  17. Polyimides Containing Carbonyl and Ether Connecting Groups

    Science.gov (United States)

    Hergenrother, Paul M.; Havens, Stephen J.

    1987-01-01

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

  18. POLYBROMINATED DIPHENYL ETHERS IN SOUTHERN MISSISSIPPI CATFISH

    Science.gov (United States)

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

  19. Organoselenium-catalyzed, hydroxy-controlled regio- and stereoselective amination of terminal alkenes: efficient synthesis of 3-amino allylic alcohols.

    Science.gov (United States)

    Deng, Zhimin; Wei, Jialiang; Liao, Lihao; Huang, Haiyan; Zhao, Xiaodan

    2015-04-17

    An efficient route to prepare 3-amino allylic alcohols in excellent regio- and stereoselectivity in the presence of bases by orangoselenium catalysis has been developed. In the absence of bases α,β-unsaturated aldehydes were formed in up to 97% yield. Control experiments reveal that the hydroxy group is crucial for the direct amination. PMID:25849818

  20. Mechanistic Dichotomy in the Asymmetric Allylation of Aldehydes with Allyltrichlorosilanes Catalyzed by Chiral Pyridine N-Oxides

    Czech Academy of Sciences Publication Activity Database

    Malkov, A. V.; Stončius, S.; Bell, M.; Castelluzzo, F.; Ramírez-López, P.; Biedermannová, Lada; Langer, V.; Rulíšek, Lubomír; Kočovský, P.

    2013-01-01

    Roč. 19, č. 28 (2013), s. 9167-9185. ISSN 0947-6539 R&D Projects: GA MŠk LC512 Institutional support: RVO:61388963 ; RVO:86652036 Keywords : allylation * allylsilanes * calculations * organocatalysis * pyridine N-oxides Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 5.696, year: 2013

  1. Synthesis of novel chiral phosphine-triazine ligand derived from α-phenylethylamine for Pd-catalyzed asymmetric allylic alkylation

    Institute of Scientific and Technical Information of China (English)

    Jia Di Huang; Xiang Ping Hu; Zhuo Zheng

    2008-01-01

    A novel chiral phosphine-triazine ligand was synthesized from chiral model reaction of Pd-catalyzed allylic alkylation of rac-l,3-diphenylprop-2-en-l-yl pivalate with dimethyl malonate, good enantioselectivity (90% e.e.) was obtained by using this ligand.

  2. Growth behavior prediction of fresh catfish fillet with Pseudomonas aeruginosa under stresses of allyl isothiocyanate, temperature and modified atmosphere

    Science.gov (United States)

    Pseudomonas aeruginosa, a common spoilage microorganism in fish, grows rapidly when temperature rises above 4 degree C. The combination of allyl isothiocyanate (AIT) and modified atmosphere (MA) was applied and proved to be effective to retard the growth of P. aeruginosa. The objective of this resea...

  3. Aldehyde Selective Wacker Oxidations of Phthalimide Protected Allylic Amines : A New Catalytic Route to beta(3)-Amino Acids

    NARCIS (Netherlands)

    Weiner, Barbara; Baeza Garcia, Alejandro; Jerphagnon, Thomas; Feringa, Ben L.

    2009-01-01

    A new method for the synthesis of B-3-amino acids is presented. Phthalimide protected allylic amines are oxidized under Wacker conditions selectively to aldehydes using PdCl2 and CuCl or Pd(MeCN)(2)Cl(NO2) and CuCl2 as complementary catalyst systems. The aldehydes are produced in excellent yields an

  4. Radiation-induced cationic curing of vinyl ethers

    International Nuclear Information System (INIS)

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

  5. Anionic membrane based on polyepichlorhydrin matrix for alkaline fuel cell: Synthesis, physical and electrochemical properties

    Energy Technology Data Exchange (ETDEWEB)

    Stoica, D.; Alloin, F. [Laboratoire d' Electrochimie et de Physico-chimie des Materiaux et des Interfaces - LEPMI, UMR 5631 CNRS-INPG-UJF, BP 75, 38402 Saint-Martin-d' Heres Cedex (France); Ogier, L. [Eras Labo, 222, RN 90, F-38330 St Nazaire-les-Eymes (France); Akrour, L.; Fauvarque, J-F. [Laboratoire d' Electrochimie Industrielle, CNAM, 2 Rue Conte, 75003 Paris (France)

    2007-12-31

    Polymer electrolytes, using a poly(epichlorydrin-allyl glycidyl ether) copolymer as matrix, were prepared and characterized. Anion conducting networks were obtained by the incorporation of two cyclic diamines named 1,4-diazabicyclo-[2.2.2]-octane (DABCO) and 1-azabicyclo-[2.2.2]-octane (Quinuclidine), neither sensitive to Hoffman elimination. In order to improve the mechanical properties, the membrane was reinforced using polyamide supports. The physicochemical and electrochemical characteristics, namely ionic exchange capacity, swelling ratio, glass transition temperature, thermal stability and ionic conductivity, were evaluated. (author)

  6. Real-Time Polymerase Chain Reaction as a Tool for Evaluation of Magnetic Poly(Glycidyl methacrylate)-Based Microspheres in Molecular Diagnostics.

    Science.gov (United States)

    Trachtová, Stepánka; Spanová, Alena; Horák, Daniel; Kozáková, Hana; Rittich, Bohuslav

    2016-01-01

    DNA amplification by real-time polymerase chain reaction (RT-PCR) was used for the evaluation of efficiency of polymer coating of magnetic hydrophilic poly(2-hydroxyethyl methacrylate-co-glycidyl methacrylate) (P(HEMA-co-GMA)) and poly(glycidyl methacrylate) (PGMA) microspheres with/without carboxyl groups. The inhibition effect of magnetic microspheres on real-time polymerase chain reaction (RT-PCR) course was evaluated by regression analysis after the addition of different concentrations of tested microspheres to PCR mixtures. Microspheres mostly did not interfere in RT-PCR till the concentration 50 µg/25 µl PCR mixture. No relationship between Fe content (and microsphere diameter) and inhibition effect was found. Microspheres containing carboxyl groups extinguished the fluorescence at lower concentrations (10-20 µg/25 µl PCR mixture) without inhibition of DNA amplification as PCR products were detected using agarose gel electrophoresis. Negative effect of maghemite on PCR course was partially reduced by coating of magnetic core by silica or polymers. Two inhibition mechanisms of DNA amplification were discussed in this work. PMID:26708828

  7. Immunocapture of CD133-positive cells from human cancer cell lines by using monodisperse magnetic poly(glycidyl methacrylate) microspheres containing amino groups

    International Nuclear Information System (INIS)

    Magnetic poly(glycidyl methacrylate)-based macroporous microspheres with an average particle size of 4.2 μm were prepared using a modified multi-step swelling polymerization method and by introducing amino functionality on their surfaces. Antibody molecules were oxidized on their carbohydrate moieties and bound to the amino-containing magnetic microspheres via a site-directed procedure. CD133-positive cells could be effectively captured from human cancer cell lines (HepG2, HCT116, MCF7, and IMR-32) by using magnetic microspheres conjugated to an anti-human CD133 antibody. After further culture, the immunocaptured CD133-expressing cells from IMR-32 proliferated and gradually detached from the magnetic microspheres. Flow-cytometric analysis confirmed the enrichment of CD133-expressing cells by using the antibody-bound magnetic microspheres. Such microspheres suitable for immunocapture are very promising for cancer diagnosis because the CD133-expressing cells in cancer cell lines have been suggested to be cancer stem cells. - Highlights: • Multi-step swelling polymerization produced poly(glycidyl methacrylate) microspheres. • Anti-human CD133 antibodies were bound to the amino-containing magnetic microspheres. • CD133-positive cells were effectively captured from human cancer cell lines. • Immunocaptured CD133-expressing cells proliferated and were detached from microspheres. • Enrichment of CD133-expressing cells was confirmed by flow-cytometric analysis

  8. Preparation and characterization of glycidyl methacrylate grafted 4-amino-1,2,4-triazole modified nonwoven fiber adsorbent for environmental application

    International Nuclear Information System (INIS)

    A novel 4-amino-1,2,4-triazole (ATZ) containing nonwoven fiber was prepared by means of radiation induced graft polymerization. For this purpose, glycidyl methacrylate (GMA) was grafted onto polyethylene coated polypropylene nonwoven fibers (NWF) in emulsion medium by using radiation induced graft polymerization. Grafting conditions were optimized and epoxy groups of grafted GMA were then modified with ATZ. Optimum conditions for modification were conducted in different solvents i.e. water and dioxane/water mixture at different amino triazole concentrations (5%, 10%, 20% (w/w)). Maximum modification was obtained in 10% (w/w) ATZ solution in dioxane/water mixture as a solvent at 80 °C. Prepared nonwoven fibers were characterized by FTIR and thermal analysis techniques. - Highlights: • Glycidyl methacrylate (GMA) was grafted onto polyethylene coated polypropylene nonwoven fibers in emulsion medium by using radiation induced graft polymerization. • Novel ATZ modified nonwoven fiber was prepared by RIGP. • Fibers were characterized by FTIR and thermal analysis techniques

  9. Poly(glycidyl methacrylate) grafted CdSe quantum dots by surface-initiated atom transfer radical polymerization: Novel synthesis, characterization, properties, and cytotoxicity studies

    Energy Technology Data Exchange (ETDEWEB)

    Bach, Long Giang; Islam, Md. Rafiqul [Department of Imaging System Engineering, Pukyong National University, Busan 608-737 (Korea, Republic of); Lee, Doh Chang [Department of Chemical and Biomolecular Engineering, KAIST Institute for the Nanocentury (KINC), Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701 (Korea, Republic of); Lim, Kwon Taek, E-mail: ktlim@pknu.ac.kr [Department of Imaging System Engineering, Pukyong National University, Busan 608-737 (Korea, Republic of)

    2013-10-15

    A novel approach for the synthesis of poly(glycidyl methacrylate) grafted CdSe quantum dot (QDs) (PGMA-g-CdSe) was developed. The PGMA-g-CdSe nanohybrids were synthesized by the surface-initiated atom transfer radical polymerization of glycidyl methacrylate from the surface of the strategic initiator, CdSe-BrIB QDs prepared by the interaction of 2-bromoisobutyryl bromide (BrIB) and CdSe-OH QDs. The structure, morphology, and optical property of the PGMA-g-CdSe nanohybrids were analyzed by FT-IR, XPS, TGA, XRD, TEM, and PL. The as-synthesized PGMA-g-CdSe nanohybrids having multi-epoxide groups were employed for the direct coupling of biotin via ring-opening reaction of the epoxide groups to afford the Biotin-f-PGMA-g-CdSe nanobioconjugate. The covalent immobilization of biotin onto PGMA-g-CdSe was confirmed by FT-IR, XPS, and EDX. Biocompatibility and imaging properties of the Biotin-f-PGMA-g-CdSe were investigated by MTT bioassay and PL analysis, respectively. The cell viability study suggested that the biocompatibility was significantly enhanced by the functionalization of CdSe QDs by biotin and PGMA.

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

    OpenAIRE

    Gibran da Cunha Vasconcelos; Rogerio Lago Mazur; Edson Cocchieri Botelho; Mirabel Cerqueira Rezende; Michelle Leali Costa

    2010-01-01

    The poly (aryl ether ketones) are used as matrices in advanced composites with high performance due to its high thermal stability, excellent environmental performance and superior mechanical properties. Most of the physical, mechanical and thermodynamic properties of semi-crystalline polymers depend on the degree of crystallinity and morphology of the crystalline regions. Thus, a study on the crystallization process promotes a good prediction of how the manufacturing parameters affect the dev...

  11. Enantioselective construction of quaternary N-heterocycles by palladium-catalysed decarboxylative allylic alkylation of lactams

    KAUST Repository

    Behenna, Douglas C.

    2011-12-18

    The enantioselective synthesis of nitrogen-containing heterocycles (N-heterocycles) represents a substantial chemical research effort and resonates across numerous disciplines, including the total synthesis of natural products and medicinal chemistry. In this Article, we describe the highly enantioselective palladium-catalysed decarboxylative allylic alkylation of readily available lactams to form 3,3-disubstituted pyrrolidinones, piperidinones, caprolactams and structurally related lactams. Given the prevalence of quaternary N-heterocycles in biologically active alkaloids and pharmaceutical agents, we envisage that our method will provide a synthetic entry into the de novo asymmetric synthesis of such structures. As an entry for these investigations we demonstrate how the described catalysis affords enantiopure quaternary lactams that intercept synthetic intermediates previously used in the synthesis of the Aspidosperma alkaloids quebrachamine and rhazinilam, but that were previously only available by chiral auxiliary approaches or as racemic mixtures. © 2012 Macmillan Publishers Limited. All rights reserved.

  12. Cutting thin sheets of allyl diglycol carbonate (CR-39) with a CW CO2, laser

    International Nuclear Information System (INIS)

    Recent studies have shown that Allyl Diglycol Carbonate, commercially known as CR-39 (the most sensitive among etch track detectors) can detect relativistic oxygen and other heavier nuclei. We are using large sheets of special grade CR-39 (DOP) in our experiment in Space Shuttle-Spacelab-3. As CR-39 is a highly brittle substance, special care is required to cut CR-39 shetts, especially in case of large sheets and circular cuts. A study of cutting of CR-39 sheets using laser light is described in this paper. It has been found that this method is sufficiently fast to handle large number of sheets and also equally safe for big sheets. A maximum speed up to 200 cm/min with a 5 x 104 W/cm2 laser is obtained during the present study. This study also shows that laser cutting does not affect the track properties of CR-39. (orig.)

  13. On the allylic hydroxylation of ent-kaurenic acid with SeO2

    Directory of Open Access Journals (Sweden)

    Alexis Peña

    2014-12-01

    Full Text Available Allylic hydroxylation of ent-kaur-16-en-19-oic acid (1a with SeO2 was tried using either dioxane or dichloro-methane as solvents as well as different reagent and reaction time conditions at room temperature. Oxidation of 1a in dioxane with H2O2 decreased reaction time but led to the formation of many by-products on addition to ent-15D-hydroxy-kaur-16-en-19-oic acid (2a, which was the main product. Using dichloromethane as solvent without addition of H2O2 made the reaction slower and yielded mainly 2a (70% at 24 h, 53% at 48 h and ent-17-oxo-kaur- 15,16-en-19-oic acid (3a,18% at 24 h, 43% at 48 h. The course of the reaction was followed by GC-MS, after methylation of the reaction mixtures.

  14. Theoretical study on the gas phase reaction of allyl chloride with hydroxyl radical.

    Science.gov (United States)

    Zhang, Yunju; Chao, Kai; Sun, Jingyu; Zhang, Wanqiao; Shi, Haijie; Yao, Cen; Su, Zhongmin; Pan, Xiumei; Zhang, Jingping; Wang, Rongshun

    2014-02-28

    The reaction of allyl chloride with the hydroxyl radical has been investigated on a sound theoretical basis. This is the first time to gain a conclusive insight into the reaction mechanism and kinetics for important pathways in detail. The reaction mechanism confirms that OH addition to the C=C double bond forms the chemically activated adducts, IM1 (CH2CHOHCH2Cl) and IM2 (CH2OHCHCH2Cl) via low barriers, and direct H-abstraction paths may also occur. Variational transition state model and multichannel RRKM theory are employed to calculate the temperature-, pressure-dependent rate constants. The calculated rate constants are in good agreement with the experimental data. At 100 Torr with He as bath gas, IM6 formed by collisional stabilization is the major products in the temperature range 200-600 K; the production of CH2CHCHCl via hydrogen abstractions becomes dominant at high temperatures (600-3000 K). PMID:24588171

  15. Low-temperature Electrodeposition of Aluminium from Lewis Acidic 1-Allyl-3-methylimidazolium Chloroaluminate Ionic Liquids

    Institute of Scientific and Technical Information of China (English)

    郑勇; 张锁江; 吕兴梅; 王倩; 左勇; 刘恋

    2012-01-01

    Lewis acidic 1-allyl-3-methylimidazolium chloroaluminate ionic liquids were used as promising electrolytes in the low-temperature electrodeposition of aluminium. Systematic studies on deposition process have been performed by cYClic voltammetry and chronoamperometry. The surface morphology and X-ray diffraction (XRD) patterns of deposits prepared at different experimental conditions were also investigated. It was shown that the nucleation density and growth rate of crystallites had a great effect on the structure of aluminium deposited. The crys- tallographic orientation of deposits was mainly influenced by temperature and current density. Smooth, dense and well adherent aluminium coatings were obtained on copper substrates at 10-25 mA.cm^-2 and 313.2-353.2 K. More- over, the current efficiency of deposition and purity of aluminium have been significantly improved, demonstrating that the ionic liquids tested have a prospectful potential in electroplating and electrorefining of aluminium.

  16. Analysis of allyl diglycol carbonate by laser induced-breakdown spectroscopy

    International Nuclear Information System (INIS)

    Laser-induced breakdown spectroscopy (LIBS) has been used to identify the impurities in the allyl diglycol carbonate, which is used as a charged particle track recording material in solid-state nuclear track detectors. Impurities of magnesium, calcium, sodium and silicon are detected. Plasma parameters such as temperature and electron density are also calculated at optimized conditions in air and argon atmosphere using the silicon lines. The temperature of the LIBS plasma produced in argon atmosphere was higher than the temperature of the LIBS plasma produced in air. Variation in the emission intensity of the carbon I line (247.8561 nm) with respect to acquisition delay and laser power is also studied. It is found that the intensities of Ca and Na lines from LIBS spectra were enhanced 30–40 times in an argon atmosphere as compared to air. Hence LIBS in an argon atmosphere can be used for better identification of impurities in plastics. (paper)

  17. Production of sorption-active polypropylene fibers by radiation-induce grafting of glycidyl methacrylate as a precursor monomer

    International Nuclear Information System (INIS)

    Full text: The design and development of sorption-active natural and synthetic polymer fibers and textile materials is of great scientific and practical interest. The advantages of that type of polymeric adsorbents, such as their highly developed specific surface, excellent ion-exchange parameters and ease of use especially under continuous conditions, allow them to find a great application in the chemical, biomedical, ecological and industrial fields. To obtain functional materials with the desired performance, the non-active polymer surface have to be modified. Among different innovative techniques used for the introduction of graft chains, the radiation-chemical method of initiation has some economical and ecological preferences over others. It allows to introduce into inert polymeric matrix chains of a monomer already containing a desirable functional group, or to graft chains of a precursor-monomer and subsequently its chemical modification to form required functional groups. At present an epoxy-group containing monomer, glycidyl methacrylate (GMA), is successfully used as a precursor-monomer for production of polymeric adsorbents of variety applications on the base of membranes, films, fibers and fabrics. Two types of sorption-active polypropylene fiber carrying strong-acid sulfonate groups and amino groups have been synthesized by radiation-induced graft polymerization of GMA, with subsequent chemical modification of the epoxy groups of poly-GMA graft chains The effect of various polymerization parameters on the GMA grafting degree was investigated in detail. The epoxy ring-opening of poly-GMA graft chains with introduction of strong-acid sulfonate groups was carried out with sodium hydrogen sulfite in water-dimethylformamide solution at 70 deg. C. The main peculiarities of the sulfonation reaction in depending on the reaction time and GMA grafting degree have been investigated. Amine groups were incorporated by treatment of the GMA-grafted polypropylene

  18. Production of sorption-active polypropylene fibers by radiation-induced grafting of glycidyl methacrylate as a precursor monomer

    International Nuclear Information System (INIS)

    The design and development of sorption-active natural and synthetic polymer fibers and textile materials is of great scientific and practical interest. The advantages of that type of polymeric adsorbents, as their highly developed specific surface, excellent ion-exchange and adsorption parameters and ease of their use especially under continuous conditions, allow them to find a great application in the chemical, biomedical, ecological and industrial fields. To obtain functional polymer materials with the desired performance, the non-active polymer surface have to be modified. Among different innovative techniques used for the introduction of graft chains, the radiation-chemical method of initiation has some economical and ecological preferences over others. It allows to introduce into inert polymeric matrix chains of a monomer already containing a desirable functional group, or to graft chains of a precursor-monomer and subsequently its chemical modification to form required functional groups. At present an epoxy-group containing monomer, glycidyl methacrylate (GMA), is successfully used as a precursor-monomer for production of polymeric adsorbents of variety applications on the base of membranes, films, fibers and fabrics. Two types of sorption-active polypropylene fiber carrying strong-acid sulfonate groups and amino groups have been synthesized by radiation-induced graft polymerization of GMA, with subsequent chemical modification of the epoxy groups of poly-GMA graft chains. The effect of various polymerization parameters on the GMA grafting degree was investigated in detail. The epoxy ring-opening of poly-GMA graft chains with introduction of strong-acid sulfonate groups was carried out with sodium hydrogen sulfite in water-dimethylformamide solution at 70 deg C. The main peculiarities of the sulfonation reaction in depending on the reaction time and GMA grafting degree have been investigated. Amine groups were incorporated by treatment of the GMA

  19. Emergent gravity and ether-drift experiments

    CERN Document Server

    Consoli, M

    2009-01-01

    In principle, ether-drift experiments could distinguish phenomenologically emergent-gravity approaches, where an effective curvature emerges from hydrodynamic distortions of the same physical, flat-space vacuum, from the more conventional scenario where curvature is considered a fundamental property of space-time down to extremely small length scales and the speed of light represents a universal constant. From an experimental point of view, in this particular context, besides time modulations that might be induced by the Earth's rotation (and its orbital revolution), one should also consider the possibility of random fluctuations of the signal. These might reflect the stochastic nature of the underlying 'quantum ether' and be erroneously interpreted as mere instrumental noise. To test the present interpretation, we have extracted the mean amplitude of the signal from various experiments with different systematics, operating both at room temperature and in the cryogenic regime. They all give the same consisten...

  20. Synthesis of New Liquid Crystalline Diglycidyl Ethers

    Directory of Open Access Journals (Sweden)

    Issam Ahmed Mohammed

    2012-01-01

    Full Text Available The phenolic Schiff bases I–VI were synthesized by condensation reactions between various diamines, namely o-dianisidine, o-tolidine and ethylenediamine with vanillin or p-hydroxybenzaldehyde and subsequent reactions between these phenolic Schiff bases and epichlorohydrin to produce new diglycidyl ethers Ia–VIa. The structures of these compounds were confirmed by CHN, FT-IR, 1H-NMR, and 13C-NMR spectroscopy. Their thermotropic liquid crystalline behavior was studied using differential scanning calorimetry (DSC and polarizing optical microscopy (POM. All the diglycidyl ethers prepared exhibit nematic mesophases, except for Va and VIa, which did not show any transition mesophases, but simply flow to liquids.

  1. Synthesis of New Liquid Crystalline Diglycidyl Ethers

    OpenAIRE

    Issam Ahmed Mohammed; Rashidah Mohamed Hamidi

    2012-01-01

    The phenolic Schiff bases I–VI were synthesized by condensation reactions between various diamines, namely o-dianisidine, o-tolidine and ethylenediamine with vanillin or p-hydroxybenzaldehyde and subsequent reactions between these phenolic Schiff bases and epichlorohydrin to produce new diglycidyl ethers Ia–VIa. The structures of these compounds were confirmed by CHN, FT-IR, 1H-NMR, and 13C-NMR spectroscopy. Their thermotropic liquid crystalline behavior was studied using differential scannin...

  2. Ether bridge formation in loline alkaloid biosynthesis

    OpenAIRE

    Pan, Juan; Bhardwaj, Minakshi; Faulkner, Jerome R.; Nagabhyru, Padmaja; Charlton, Nikki D.; Higashi, Richard M.; Miller, Anne-Frances; Young, Carolyn A; Grossman, Robert B.; Schardl, Christopher L

    2013-01-01

    Lolines are potent insecticidal agents produced by endophytic fungi of cool-season grasses. These alkaloids are composed of a pyrrolizidine ring system and an uncommon ether bridge linking carbons 2 and 7. Previous results indicated that 1-aminopyrrolizidine was a pathway intermediate. We used RNA interference to knock down expression of lolO, resulting in the accumulation of a novel alkaloid identified as exo-1-acetamidopyrrolizidine based on high-resolution MS and NMR. Genomes of endophytes...

  3. Fluoroalkylation of aryl ether perfluorocyclobutyl polymers

    OpenAIRE

    Ligon, Clark; Ameduri, Bruno; Boutevin, Bernard; Smith, Dennis

    2008-01-01

    Post functionalization of aryl ether perfluorocyclobutyl (PFCB) polymers with fluoroalkyl side chains was accomplished with Umemoto's FITS reagents. The fluoroalkylated PFCB polymers (20 % functionalized) showed increases in both hydrophobicity and oleophobicity. Static contact angle for hexadecane was increased after fluoroalkylation from 0° to greater than 30° for the two PFCB polymers tested. Increased oil repellency makes these materials potential candidates for various coatings applicati...

  4. Model for Photodegradation of Polybrominated Diphenyl Ethers

    Czech Academy of Sciences Publication Activity Database

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

    2015-01-01

    Roč. 22, č. 7 (2015), s. 4949-4963. ISSN 0944-1344 R&D Projects: GA ČR GA104/09/0880; GA ČR(CZ) GAP105/12/0664 Institutional support: RVO:67985858 ; RVO:67179843 Keywords : polybrominated diphenyl ethers * photodegradation model * quantum chemical calculation Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 2.828, year: 2014

  5. Catalytic intermolecular hydroamination of vinyl ethers

    OpenAIRE

    Pahadi, Nirmal K.; Tunge, Jon A.

    2009-01-01

    This manuscript details the development of a palladium-catalyzed hydroamination of vinyl ethers. It is proposed that palladium catalyzes the hydroamination via Bronsted base catalysis, where palladium is protonated by the relatively acidic sulfonamide to generate a palladium hydride as well as the active anionic sulfonamide nucleophile. Thus, this process is distinct from known palladium-catalyzed hydroaminations of styrene derivatives that utilize less acidic amines.

  6. Poly(Arylene Ether Imidazole) Surface Films

    Science.gov (United States)

    Connell, John W.; Towell, Timothy W.; Tompkins, Stephen S.

    1993-01-01

    Films adhere well to some substrates, provide smooth surfaces, and facilitate release from molds. Thin films of thermoplastic poly(arylene ether imidazole)s (PAEI's) particularly suitable for use as surface modifiers for graphite/epoxy or graphite/bismaleimide composite panels. Molecule of PAEI includes imidazole groups along its backbone that co-cure with epoxies or bismaleimides during processing. Films thermally stable and resistant to bombardment by energetic electrons.

  7. The solubility and environmental characteristics of diesel ethers

    International Nuclear Information System (INIS)

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

  8. Nikola Tesla, the Ether and his Telautomaton

    Science.gov (United States)

    Milar, Kendall

    2014-03-01

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

  9. Alkyl aryl ethers in lignite solubilization

    Energy Technology Data Exchange (ETDEWEB)

    Mustral, A.M.; Cebolla, V.L.; Gavilan, J.M.

    1985-03-01

    The FT-I.R. and /sup 1/H N.M.R. spectroscopic analyses of oils or maltenes from a Spanish lignite (Utrillas, Teruel), are reported. These oils were obtained by depolymerization with alkyl aromatic ethers (anisole, 3-methyl anisole and 1,3-dimethoxybenzene) catalyzed by Lewis acids ZnCl/sub 2/, AlCl/sub 3/, SbCl/sub 3/ and BF/sub 3/ (as boron trifluoride etherate), at atmospheric pressure and temperatures <220/sup 0/C. Bands due to aromatic ethers in the I.R. and N.M.R. spectra of the oils obtained by depolymerization indicate solvent incorporation. Oils obtained by direct lignite extraction showed 25% aromatic H and some H /sub i/ (approx. = 3%) without OH groups. These appeared in some oils obtained by depolymerization with AlCl/sub 3/ and were due to secondary reactions with the aromatic extract. Oils derived from processes with good yields showed increases in aromaticity. The extent of substitution of aromatic rings in oils obtained by depolymerization was less than for oils directly extracted. All the oils studied show a low degree of condensation.

  10. Formation of gold clusters on La-Ni mixed oxides and its catalytic performance for isomerization of allylic alcohols to saturated aldehydes

    International Nuclear Information System (INIS)

    Au/NiO catalyzed the isomerization of allylic alcohols to afford saturated aldehydes. La-Ni mixed oxide could stabilize Au(III) and afford gold clusters smaller than 1 nm by H2 reduction. The resulting Au clusters on La-Ni-O exhibited superior catalytic performance to Au/NiO for the isomerization of internal allylic alcohol, 2-octen-1-ol to octanal. (author)

  11. The reaction mechanism of the enantioselective Tsuji allylation: inner-sphere and outer-sphere pathways, internal rearrangements, and asymmetric C–C bond formation

    OpenAIRE

    Keith, John A.; Behenna, Douglas C.; Sherden, Nathaniel; Mohr, Justin T.; Ma, Sandy; Marinescu, Smaranda C.; Nielsen, Robert J.; Oxgaard, Jonas; Stoltz, Brian M.; Goddard, William A.

    2012-01-01

    We use first principles quantum mechanics (density functional theory) to report a detailed reaction mechanism of the asymmetric Tsuji allylation involving prochiral nucleophiles and nonprochiral allyl fragments, which is consistent with experimental findings. The observed enantioselectivity is best explained with an inner-sphere mechanism involving the formation of a 5-coordinate Pd species that undergoes a ligand rearrangement, which is selective with regard to the prochiral faces of the int...

  12. An Efficient Protocol for the Palladium-Catalyzed Asymmetric Decarboxylative Allylic Alkylation Using Low Palladium Concentrations and a Palladium(II) Precatalyst

    OpenAIRE

    Marziale, Alexander N.; Duquette, Douglas C.; Craig, Robert A.; Kim, Kelly E.; Liniger, Marc; Numajiri, Yoshitaka; Stoltz, Brian M.

    2015-01-01

    Enantioselective catalytic allylic alkylation for the synthesis of 2-alkyl-2-allylcycloalkanones and 3,3-disubstituted pyrrolidinones, piperidinones and piperazinones has been previously reported by our laboratory. The efficient construction of chiral all-carbon quaternary centers by allylic alkylation was previously achieved with a catalyst derived in situ from zero-valent palladium sources and chiral phosphinooxazoline (PHOX) ligands. We now report an improved reaction protocol with broad a...

  13. An Efficient Protocol for the Palladium-catalyzed Asymmetric Decarboxylative Allylic Alkylation Using Low Palladium Concentrations and a Palladium(II) Precatalyst

    OpenAIRE

    Marziale, Alexander N.; Duquette, Douglas C.; Craig, Robert A.; Kim, Kelly E.; Liniger, Marc; Numajiri, Yoshitaka; Stoltz, Brian M.

    2015-01-01

    Enantioselective catalytic allylic alkylation for the synthesis of 2-alkyl-2-allylcycloalkanones and 3,3-disubstituted pyrrolidinones, piperidinones and piperazinones has been previously reported by our laboratory. The efficient construction of chiral all-carbon quaternary centers by allylic alkylation was previously achieved with a catalyst derived in situ from zero valent palladium sources and chiral phosphinooxazoline (PHOX) ligands. We now report an improved reaction protocol with broad a...

  14. A chemical assessment of the suitability of allyl- iso-propyltelluride as a Te precursor for metal organic vapour phase epitaxy

    Science.gov (United States)

    Hails, Janet E.; Cole-Hamilton, David J.; Stevenson, John; Bell, William; Foster, Douglas F.; Ellis, David

    2001-04-01

    The chemical studies, which led to the testing of allyl- iso-propyltelluride (allylTePr i) as a Te precursor in metal organic vapour phase epitaxy are presented. The pyrolysis in hydrogen of allylTePr i gave products including 1,5-hexadiene, propane and propene. Co-pyrolysis of dimethylcadmium (Me 2Cd) and allylTePr i gave the hydrocarbons expected from the pyrolysis of the individual precursors plus additional hydrocarbons including 2-methylpropane and 1-butene. Plots of percentage decomposition versus temperature, which proved extremely useful in determining the likely growth temperatures for both CdTe and HgTe, showed that allylTePr i is less stable than both Pr 2iTe (di- iso-propyltelluride) and Me 2Cd. The possible role of Hg in the growth of CdTe is also discussed. The chemistry of allylTePr i is well suited for use as an efficient precursor for epitaxial growth of tellurium containing semiconductors since there is very little formation of other organotellurium compounds on pyrolysis.

  15. Electroless nickel-phosphorus coating on poly (ether ether ketone)/carbon nanotubes composite

    Science.gov (United States)

    Zhai, Tong; Di, Lizhi; Yang, De'an

    2014-05-01

    In order to improve electromagnetic shielding property of poly (ether ether ketone)/carbon nanotubes composite, a nickel-phosphorus coating was covered on the composite by electroless plating. The morphologies of the substrates and the coatings were characterized by SEM. XPS was performed to analyze the surface composition and chemical states before and after chemical etching. The results showed that lots of microscopic holes appeared and evenly distributed on the surface, and the concentration of hydrophilic groups on the surface increased after the composite was etched. Thermal shock test showed that the adhesive strength between the coating and the composite was good.

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

    Science.gov (United States)

    Cappello, Miriam; Lamia, Pietro; Mura, Claudio; Polacco, Giovanni; Filippi, Sara

    2016-07-01

    Polymeric binders for solid propellants are usually based on hydroxyl-terminated polybutadiene (HTPB), which does not contribute to the overall energy output. Azidic polyethers represent an interesting alternative but may have poorer mechanical properties. Polybutadiene-polyether copolymers may combine the advantages of both. Four different ether-butadiene-ether triblock copolymers were prepared and azidated starting from halogenated and/or tosylated monomers using HTPB as initiator. The presence of the butadiene block complicates the azidation step and reduces the storage stability of the azidic polymer. Nevertheless, the procedure allows modifying the binder properties by varying the type and lengths of the energetic blocks.

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

    International Nuclear Information System (INIS)

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

  18. Absorption of some glycol ethers through human skin in vitro.

    OpenAIRE

    Dugard, P H; M. Walker; Mawdsley, S J; Scott, R.C.

    1984-01-01

    To assist evaluation of the hazards of skin contact with selected undiluted glycol ethers, their absorption across isolated human abdominal epidermis was measured in vitro. Epidermal membranes were set up in glass diffusion cells and, following an initial determination of permeability to tritiated water, excess undiluted glycol ether was applied to the outer surface for 8 hr. The appearance of glycol ether in an aqueous "receptor" phase bathing the underside of the epidermis was quantified by...

  19. SYNTHESIS OF POLY ( ETHER-URETHANE) CONTAINING PENDANT AMINO GROUP

    Institute of Scientific and Technical Information of China (English)

    WU Jinhuang; SUN Yanhui; FENG Xinde

    1989-01-01

    This paper is concerned with the synthesis of poly (ether-urethane) with pendant amino groups. The copolyether produced by ring opening copolymerization of tetrahydrofuran and epibromohydrin was treated with sodium azide in dimethylformamide to form azido substituted copolyether. The poly (ether-urethane) made from it was subjected to reduction reaction to convert azido group to amino group. The stress-strain behavior and dynamic-mechanical properties of poly (ether-urethane) containing pendant amino groups were studied.

  20. Crystal structure of (Z-3-allyl-5-(3-bromobenzylidene-2-sulfanylidene-1,3-thiazolidin-4-one

    Directory of Open Access Journals (Sweden)

    Rahhal El Ajlaoui

    2015-12-01

    Full Text Available In the title compound, C13H10BrNOS2, the rhodanine (systematic name: 2-sulfanylidene-1,3-thiazolidin-4-one and the 3-bromobenzylidene ring systems are inclined slightly, forming a dihedral angle of 5.86 (12°. The rhodanine moiety is linked to an allyl group at the N atom and to the 3-bromobenzylidene ring system. The allyl group, C=C—C, is nearly perpendicular to the mean plane through the rhodanine ring, maling a dihedral angle of 87.2 (5°. In the crystal, molecules are linked by pairs of C—H...O hydrogen bonds, forming inversion dimers with an R22(10 ring motif.

  1. Synthesis and uranyl ion adsorption study of cross-linked allyl propionate-maleic anhydride-styrene terpolymer

    OpenAIRE

    AKPEROV, Elchin; MAHARRAMOV, Abel; AKPEROV, Oktay

    2010-01-01

    Allyl propionate-maleic anhydride-styren terpolymer has been modified with glycerin in order to prepare a new cross-linked functional polymer sorbent. The synthesized cross-linked polymer sorbent has a network structure and contains carboxylic acid, carbonyl, hydroxy, and ester groups, all of which are capable ofinteracting with metal ions. The sorption behavior of UO22+ ions under optimum sorption conditions was determined. The sorption properties of the sorbent were determined unde...

  2. Preparation and reactivity of metal-containing monomers. Communication 2. Radiation graft polymerization of allyl alcohol complexed on polyethylene

    International Nuclear Information System (INIS)

    A study of the postradiation graft polymerization of complexed allyl alcohol was carried out for the first time. Copolymers were obtained containing up to 2.4 mass % polyallyl alcohol and 2.4 mass % metal. The grafting rate is constant for several hours and increases with an increase in the concentration of the complexing agent in the reaction mixture up to [CoCl2]:[AA] mole ratio equal to 1:5

  3. Antioxidant and Hypolipidemic Potential of Aged Garlic Extract and Its Constituent, S-Allyl Cysteine, in Rats

    OpenAIRE

    Syed Mohammed Basheeruddin Asdaq

    2015-01-01

    Aged garlic extract (AGE) is one of the unique preparations standardized with 100% bioavailable active ingredients found in the bloodstream. The current research was aimed at exploring the role of AGE and its chief active constituent, s-allyl cysteine (SAC) as antioxidant and hypolipidemic agent in rats. At the end of treatment of AGE and SAC, separated serum and freshly prepared liver tissue homogenate were analyzed for biochemical enzymes and biomarkers to evaluate and compare potencies of ...

  4. Hydroxymethylation beyond Carbonylation: Enantioselective Iridium-Catalyzed Reductive Coupling of Formaldehyde with Allylic Acetates via Enantiotopic π-Facial Discrimination.

    Science.gov (United States)

    Garza, Victoria J; Krische, Michael J

    2016-03-23

    Chiral iridium complexes modified by SEGPHOS catalyze the 2-propanol-mediated reductive coupling of branched allylic acetates 1a-1o with formaldehyde to form primary homoallylic alcohols 2a-2o with excellent control of regio- and enantioselectivity. These processes, which rely on enantiotopic π-facial discrimination of σ-allyliridium intermediates, represent the first examples of enantioselective formaldehyde C-C coupling beyond aldol addition. PMID:26958737

  5. Statistic evaluation of cysteine and allyl alcohol as additives for Cu-Zn coatings from citrate baths

    OpenAIRE

    Julyana Ribeiro Garcia; Dalva Cristina Baptista do Lago; Fernando Lucas Gonçalves Silva; Eliane D'Elia; Aderval Severino Luna; Lilian Ferreira de Senna

    2013-01-01

    In the present work, cysteine and allyl alcohol were added to citrate baths as additives to Cu-Zn coatings on steel substrates. In order to verify the effects of the deposition parameters (current density, mechanical stirring speed, and additives) on the coating composition, electrochemical behavior, morphology, and microstructure properties of Cu-Zn coatings, the electrodeposition of the alloy was carried out using an experimental composite design 2³, in which these parameters were considere...

  6. Rhodium(III)-catalyzed C-C coupling of 7-azaindoles with vinyl acetates and allyl acetates.

    Science.gov (United States)

    Li, Shuai-Shuai; Wang, Cheng-Qi; Lin, Hui; Zhang, Xiao-Mei; Dong, Lin

    2016-01-01

    The behaviour of electron-rich alkenes with 7-azaindoles in rhodium(III)-catalyzed C-H activation is investigated. Various substituted vinyl acetates and allyl acetates as coupling partners reacted smoothly providing a wide variety of 7-azaindole derivatives, and the selectivity of the coupling reaction is alkene-dependent. In addition, the approaches of rhodium(III)-catalyzed dehydrogenative Heck-type reaction (DHR) and carbonylation reaction were quite novel and simple. PMID:26553424

  7. Synchrotron Photoionization Mass Spectrometry Measurements of Kinetics and Product Formation in the Allyl Radical (H2CCHCH2)Self Reaction

    Science.gov (United States)

    Selby, Talitha M.; Melini, giovanni; Goulay, Fabien; Leone, Stephen R.; Fahr, Askar; Taatjes, Craig A.; Osborn, David L.

    2008-01-01

    Product channels for the self-reaction of the resonance-stabilized allyl radical, C3H5 + C3H5, have been studied with isomeric specificity at temperatures from 300-600 K and pressures from 1-6 Torr using time-resolved multiplexed photoionization mass spectrometry. Under these conditions 1,5-hexadiene was the only C6H10 product isomer detected. The lack of isomerization of the C6H10 product is in marked contrast to the C6H6 product in the related C3H3 + C3H3 reaction, and is due to the more saturated electronic structure of the C6H10 system. The disproportionation product channel, yielding allene + propene, was also detected, with an upper limit on the branching fraction relative to recombination of 0.03. Analysis of the allyl radical decay at 298 K yielded a total rate coefficient of (2.7 +/- 0.8) x 10(exp -11) cu cm/molecule/s, in good agreement with pre.vious experimental measurements using ultraviolet kinetic absorption spectroscopy and a recent theoretical determination using variable reaction coordinate transition state theory. This result provides independent indirect support for the literature value of the allyl radical ultraviolet absorption cross-section near 223 nm.

  8. Regioselective synthesis of novel 3-allyl-2-(substituted imino)-4-phenyl-3H-thiazole and 2,2‧-(1,3-phenylene)bis(3-substituted-2-imino-4-phenyl-3H-thiazole) derivatives as antibacterial agents

    Science.gov (United States)

    Abbasi Shiran, Jafar; Yahyazadeh, Asieh; Mamaghani, Manouchehr; Rassa, Mehdi

    2013-05-01

    Several novel 3-allyl-2-(substituted imino)-4-phenyl-3H-thiazole derivatives were synthesized by the reaction of allyl-thioureas and 2-bromoacetophenone. We also report the synthesis of bis-allyl-3H thiazoles using the reaction of various isothiocyanates and 1,3-phenylenediamine. The structures of all compounds were characterized by spectral and elemental analysis. Most of the synthesized compounds exhibited efficient antibacterial activities against Salmonella enterica, Micrococcus luteus, Bacillus subtilis and Pseudomonas aeruginosa.

  9. Monodisperse carboxyl-functionalized poly(ethylene glycol)-coated magnetic poly(glycidyl methacrylate) microspheres: application to the immunocapture of β-amyloid peptides.

    Science.gov (United States)

    Horák, Daniel; Hlídková, Helena; Hiraoui, Mohamed; Taverna, Myriam; Proks, Vladimír; Mázl Chánová, Eliška; Smadja, Claire; Kučerová, Zdenka

    2014-11-01

    Identification and evaluation of small changes in β-amyloid peptide (Aβ) levels in cerebrospinal fluid is of crucial importance for early detection of Alzheimer's disease. Microfluidic detection methods enable effective preconcentration of Aβ using magnetic microparticles coated with Aβ antibodies. Poly(glycidyl methacrylate) microspheres are coated with α-amino-ω-methoxy-PEG5000 /α-amino-ω-Boc-NH-PEG5000 Boc groups deprotected and NH2 succinylated to introduce carboxyl groups. Capillary electrophoresis with laser-induced fluorescence detection confirms the efficient capture of Aβ 1-40 peptides on the microspheres with immobilized monoclonal anti-Aβ 6E10. The capture specificity is confirmed by comparing Aβ 1-40 levels on the anti-IgG-immobilized particles used as a control. PMID:25142028

  10. Radiation-induced graft polymerization and sulfonation of glycidyl methacrylate on to porous hollow-fiber membranes with different pore sizes

    International Nuclear Information System (INIS)

    An epoxy group containing monomer, glycidyl methacrylate, was grafted on to a porous hollow-fiber membrane, made of polyethylene, whose different pore sizes ranged from 0.2 to 0.5 μm. The resulting epoxy group was converted into a sulfonic acid group as a cation-exchange group to capture metal ions. The porous network was retained after grafting and subsequent sulfonation because the poly-GMA chains invaded the polymer matrix. An increase in the SO3H group density of the graft chain decreased the permeability of pure water because the graft chains expanded toward the pore interior due to their mutual electrostatic repulsion. The ion-exchange adsorption of Pb ions during the permeation of a Pb(NO3)2 solution through the pores edged by the cation-exchange graft chains was observed with a negligible diffusional mass-transfer resistance. (author)

  11. Preparation and characterization of reactive blends of poly(lactic acid), poly(ethylene-co-vinyl alcohol), and poly(ethylene-co-glycidyl methacrylate)

    International Nuclear Information System (INIS)

    The ternary blends of poly(lactic acid) (PLA), poly(ethylene-co-vinyl alcohol) (EVOH), and poly(ethylene-co-glycidyl methacrylate) (EGMA) were prepared. The role of EGMA as a compatibilizer was evaluated. The weight ratio of PLA:EVOH was 80:20 and the EGMA loadings were varied from 5-20 phr. The blends were characterized as follows: thermal properties by differential scanning calorimetry, morphology by scanning electron microscopy, and mechanical properties by pendulum impact tester, and universal testing machine. The glass transition temperature of PLA blends did not change much when compared with that of PLA. The blends of PLA/EGMA and EVOH/EGMA showed EGMA dispersed droplets where the latter led to poor impact properties. However, the tensile elongation at break and tensile toughness substantially increased upon addition of EGMA to blends of PLA and EVOH. It was noted in tensile test samples that both PLA and EVOH domains fibrillated significantly to produce toughness

  12. Preparation and characterization of reactive blends of poly(lactic acid), poly(ethylene-co-vinyl alcohol), and poly(ethylene-co-glycidyl methacrylate)

    Energy Technology Data Exchange (ETDEWEB)

    Warangkhana, Phromma; Rathanawan, Magaraphan, E-mail: rathanawan.k@chula.ac.th [Chulalongkorn University, Petroleum and Petrochemical College - Bangkok (Thailand); Jana Sadhan, C., E-mail: janas@uakron.edu [The University of Akron, Department of Polymer Engineering, Ohio (United States)

    2015-05-22

    The ternary blends of poly(lactic acid) (PLA), poly(ethylene-co-vinyl alcohol) (EVOH), and poly(ethylene-co-glycidyl methacrylate) (EGMA) were prepared. The role of EGMA as a compatibilizer was evaluated. The weight ratio of PLA:EVOH was 80:20 and the EGMA loadings were varied from 5-20 phr. The blends were characterized as follows: thermal properties by differential scanning calorimetry, morphology by scanning electron microscopy, and mechanical properties by pendulum impact tester, and universal testing machine. The glass transition temperature of PLA blends did not change much when compared with that of PLA. The blends of PLA/EGMA and EVOH/EGMA showed EGMA dispersed droplets where the latter led to poor impact properties. However, the tensile elongation at break and tensile toughness substantially increased upon addition of EGMA to blends of PLA and EVOH. It was noted in tensile test samples that both PLA and EVOH domains fibrillated significantly to produce toughness.

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

    International Nuclear Information System (INIS)

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

  14. Unprecedented reactions: from epichlorohydrin to epoxyglycidyl substituted divinyl ether and its conversion into epoxyglycidyl propargyl ether

    Science.gov (United States)

    Yao, Yiwu; Li, Zheng; Qiu, Yatao; Bai, Jinhong; Su, Jinyue; Zhang, Dayong; Jiang, Sheng

    2015-09-01

    The reaction of epichlorohydrin with concentrated sodium hydroxide in hexane under phase transfer conditions has surprisingly led to the formation of the symmetrical di(3-epoxyglycidyl-1-propenyl) ether 1 which contains both nucleophilic and electrophilic moieties. When it was reacted with n-butyllithium, intermediate 1 once again surprisingly generated epoxyglycidyl propargyl ether, which was further reacted in situ with a variety of benzaldehydes to furnish the corresponding substituted propargylic alcohols in good yields. While the reaction is operationally simple, it provides a powerful method for the synthesis of the important products from commodity materials such as epichlorohydrin. Moreover, these reactions may have revealed that some fundamental properties of the hydroxide anion in those once thought straightforward reactions are not well understood. A careful analysis of the experimental data suggests that an unprecedented concerted elimination of the epoxyglycidyl ether with sodium hydroxide may be operative and an alpha deprotonation followed by alpha elimination of the di(3-epoxyglycidyl-1-propenyl) ether with alkyllithium may have been involved.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-10-01

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

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

    International Nuclear Information System (INIS)

    All solid supercapacitor based on polyaniline (PANI) and crosslinked sulfonated poly[ether ether ketone] (XSPEEK,) is reported in this paper. The crosslinker used for sulfonated poly[ether ether ketone] (SPEEK) is 1,4-bis(hydroxymethyl) benzene. The XSPEEK is used as both solid electrolyte and separator membrane. Supercapacitors are fabricated using various PANI/XSPEEK weight ratios. These are characterized by cyclic voltammetry and galvanostatic charge-discharge studies. The supercapacitor with PANI/XSPEEK weight ratio 1:0.5, exhibit a specific capacitance of 480 F g-1 of PANI. To the best of authors' knowledge, the value reported here is the highest for a supercapacitor based on a proton conducting solid polymer electrolyte and PANI. Detailed electrochemical impedance spectroscopy analysis is carried out. The analysis shows that the complex capacitance of the supercapacitor depends on the XSPEEK content. The time constant (t0), derived from the imaginary part of complex capacitance decreases with increase in the XSPEEK content in the supercapacitor. Cycle life characteristics of the supercapacitor show a decrease in specific capacitance during initial cycles and get stabilized during later cycles.

  17. Copper Promoted Synthesis of Diaryl Ethers

    OpenAIRE

    Ghosh, Rajshekhar; Samuelson, Ashoka G

    2004-01-01

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

  18. 烯丙基酚醛树脂的固化动力学%Curing Kinetics of Allyl Phenolic Resin

    Institute of Scientific and Technical Information of China (English)

    刘洋; 刘诗薇; 李志强; 于景坤

    2012-01-01

    The curing behavior of allyl phenolic resin was analyzed at different heating rates using differential scanning calorimetry.The obtained kinetic data were treated by Kissinger and KAS(Kissinger-Akahira-Sunose) methods to obtain the curing reaction kinetic parameters.A curing kinetics model was established for allyl phenolic resin.Compared with phenolic resin,the curing temperature of allyl phenolic resin is higher,the reaction order is closer to 1,and the average activation energy of the curing reaction is lower,111.45 kJ/mol.The activation energy of allyl phenolic resin is almost constant and changes little with temperature in the curing process.The curing kinetics model of allyl phenolic resin provides a theoretical basis for the study of curing process parameters.%利用差示扫描量热法分析了烯丙基酚醛树脂在不同升温速率下的固化行为,用Kissinger法和KAS(Kissinger-Akahira-Sunose)法对获得的动力学数据进行处理,得到了固化反应动力学参数,并建立了烯丙基酚醛树脂的固化动力学模型.结果表明:与纯酚醛树脂相比,烯丙基酚醛树脂固化温度较高,反应级数更接近于1,固化反应所需的平均表观活化能较低,为111.45kJ/mol;在整个固化过程中,烯丙基酚醛树脂的活化能较为恒定,随温度变化不大;烯丙基酚醛树脂固化动力学模型为研究该体系固化工艺参数提供了理论依据.

  19. Application of simplified PC-SAFT to glycol ethers

    DEFF Research Database (Denmark)

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

    2012-01-01

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

  20. Synthesis and Biophysical Characterization of Chlorambucil Anticancer Ether Lipid Prodrugs

    DEFF Research Database (Denmark)

    Pedersen, Palle Jacob; Christensen, Mikkel Stochkendahl; Ruysschaert, Tristan;

    2009-01-01

    The synthesis and biophysical characterization of four prodrug ether phospholipid conjugates are described. The lipids are prepared from the anticancer drug chlorambucil and have C16 and C18 ether chains with phosphatidylcholine or phosphatidylglycerol headgroups. All four prodrugs have the abili...

  1. Congenital malformations and maternal occupational exposure to glycol ethers

    NARCIS (Netherlands)

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

    1997-01-01

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

  2. Allyl m-Trifluoromethyldiazirine Mephobarbital: An Unusually Potent Enantioselective and Photoreactive Barbiturate General Anesthetic

    Energy Technology Data Exchange (ETDEWEB)

    Savechenkov, Pavel Y.; Zhang, Xi; Chiara, David C.; Stewart, Deirdre S.; Ge, Rile; Zhou, Xiaojuan; Raines, Douglas E.; Cohen, Jonathan B.; Forman, Stuart A.; Miller, Keith W.; Bruzik, Karol S. (Harvard-Med); (Mass. Gen. Hosp.); (UIC)

    2012-12-10

    We synthesized 5-allyl-1-methyl-5-(m-trifluoromethyl-diazirynylphenyl)barbituric acid (14), a trifluoromethyldiazirine-containing derivative of general anesthetic mephobarbital, separated the racemic mixture into enantiomers by chiral chromatography, and determined the configuration of the (+)-enantiomer as S by X-ray crystallography. Additionally, we obtained the {sup 3}H-labeled ligand with high specific radioactivity. R-(-)-14 is an order of magnitude more potent than the most potent clinically used barbiturate, thiopental, and its general anesthetic EC{sub 50} approaches those for propofol and etomidate, whereas S-(+)-14 is 10-fold less potent. Furthermore, at concentrations close to its anesthetic potency, R-(-)-14 both potentiated GABA-induced currents and increased the affinity for the agonist muscimol in human {alpha}1{beta}2/3{gamma}2L GABA{sub A} receptors. Finally, R-(-)-14 was found to be an exceptionally efficient photolabeling reagent, incorporating into both {alpha}1 and {beta}3 subunits of human {alpha}1{beta}3 GABAA receptors. These results indicate R-(-)-14 is a functional general anesthetic that is well-suited for identifying barbiturate binding sites on Cys-loop receptors.

  3. Enhanced biocompatibility and wound healing properties of biodegradable polymer-modified allyl 2-cyanoacrylate tissue adhesive.

    Science.gov (United States)

    Lee, Young Ju; Son, Ho Sung; Jung, Gyeong Bok; Kim, Ji Hye; Choi, Samjin; Lee, Gi-Ja; Park, Hun-Kuk

    2015-06-01

    As poly L-lactic acid (PLLA) is a polymer with good biocompatibility and biodegradability, we created a new tissue adhesive (TA), pre-polymerized allyl 2-cyanoacrylate (PACA) mixed with PLLA in an effort to improve biocompatibility and mechanical properties in healing dermal wound tissue. We determined optimal mixing ratios of PACA and PLLA based on their bond strengths and chemical structures analyzed by the thermal gravimetric analysis (TGA) and Fourier transform infrared (FT-IR) spectroscopy. In vitro biocompatibility of the PACA/PLLA was evaluated using direct- and indirect-contact methods according to the ISO-10993 cytotoxicity test for medical devices. The PACA/PLLA have similar or even better biocompatibility than those of commercially available cyanoacrylate (CA)-based TAs such as Dermabond® and Histoacryl®. The PACA/PLLA were not different from those exposed to Dermabond® and Histoacryl® in Raman spectra when biochemical changes of protein and DNA/RNA underlying during cell death were compared utilizing Raman spectroscopy. Histological analysis revealed that incised dermal tissues of rats treated with PACA/PLLA showed less inflammatory signs and enhanced collagen formation compared to those treated with Dermabond® or Histoacryl®. Of note, tissues treated with PACA/PLLA were stronger in the tensile strength compared to those treated with the commercially available TAs. Therefore, taking all the results into consideration, the PACA/PLLA we created might be a clinically useful TA for treating dermal wounds. PMID:25842106

  4. Increased presevation of sliced mozzarella cheese by antimibrobial sachet incorporated with allyl isothiocyanate

    Directory of Open Access Journals (Sweden)

    Ana Clarissa dos Santos Pires

    2009-12-01

    Full Text Available There is an increasing tendency to add natural antimicrobials of plant origin into food. The objective of this work was to develop a microbial sachet incorporated with allyl isothiocyanate (AIT, a volatile compound of plant origin, and to test its efficiency against growth of yeasts and molds, Staphylococcus sp. and psychrotrophic bacteria on sliced mozzarella cheese. Another objective was to quantify the concentration of AIT in the headspace of cheese packaging. A reduction of 3.6 log cycles was observed in yeasts and molds counts in the mozzarella packed with the antimicrobial sachet over 15-day storage time. The sachet also showed an antibacterial effect on Staphylococcus sp., reducing 2.4 log cycles after 12-day storage. Psychrotrophic bacteria species were the most resistant to the antimicrobial action. The highest concentration of AIT (0.08µg.mL-1 inside the active packaging system was observed at the 6-day of storage at 12 ºC ± 2 ºC. At the end of the storage time, AIT concentration decreased to only 10% of the initial concentration. Active packaging containing antimicrobial sachet has a potential use for sliced mozzarella, with molds and yeasts being the most sensitive to the antimicrobial effects.

  5. Allyl isothiocyanates and cinnamaldehyde potentiate miniature excitatory postsynaptic inputs in the supraoptic nucleus in rats.

    Science.gov (United States)

    Yokoyama, Toru; Ohbuchi, Toyoaki; Saito, Takeshi; Sudo, Yuka; Fujihara, Hiroaki; Minami, Kouichiro; Nagatomo, Toshihisa; Uezono, Yasuhito; Ueta, Yoichi

    2011-03-25

    Allyl isothiocyanates (AITC) and cinnamaldehyde are pungent compounds present in mustard oil and cinnamon oil, respectively. These compounds are well known as transient receptor potential ankyrin 1 (TRPA1) agonists. TRPA1 is activated by low temperature stimuli, mechanosensation and pungent irritants such as AITC and cinnamaldehyde. TRPA1 is often co-expressed in TRPV1. Recent study showed that hypertonic solution activated TRPA1 as well as TRPV1. TRPV1 is involved in excitatory synaptic inputs to the magnocellular neurosecretory cells (MNCs) that produce vasopressin in the supraoptic nucleus (SON). However, it remains unclear whether TRPA1 may be involved in this activation. In the present study, we examined the role of TRPA1 on the synaptic inputs to the MNCs in in vitro rat brain slice preparations, using whole-cell patch-clamp recordings. In the presence of tetrodotoxin, AITC (50μM) and cinnamaldehyde (30μM) increased the frequency of miniature excitatory postsynaptic currents without affecting the amplitude. This effect was significantly attenuated by previous exposure to ruthenium red (10μM), non-specific TRP channels blocker, high concentration of menthol (300μM) and HC-030031 (10μM), which are known to antagonize the effects of TRPA1 agonists. These results suggest that TRPA1 may exist at presynaptic terminals to the MNCs and enhance glutamate release in the SON. PMID:21266172

  6. Allyl Isothiocyanate Inhibits Actin-Dependent Intracellular Transport in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Bjørnar Sporsheim

    2015-12-01

    Full Text Available Volatile allyl isothiocyanate (AITC derives from the biodegradation of the glucosinolate sinigrin and has been associated with growth inhibition in several plants, including the model plant Arabidopsis thaliana. However, the underlying cellular mechanisms of this feature remain scarcely investigated in plants. In this study, we present evidence of an AITC-induced inhibition of actin-dependent intracellular transport in A. thaliana. A transgenic line of A. thaliana expressing yellow fluorescent protein (YFP-tagged actin filaments was used to show attenuation of actin filament movement by AITC. This appeared gradually in a time- and dose-dependent manner and resulted in actin filaments appearing close to static. Further, we employed four transgenic lines with YFP-fusion proteins labeling the Golgi apparatus, endoplasmic reticulum (ER, vacuoles and peroxisomes to demonstrate an AITC-induced inhibition of actin-dependent intracellular transport of or, in these structures, consistent with the decline in actin filament movement. Furthermore, the morphologies of actin filaments, ER and vacuoles appeared aberrant following AITC-exposure. However, AITC-treated seedlings of all transgenic lines tested displayed morphologies and intracellular movements similar to that of the corresponding untreated and control-treated plants, following overnight incubation in an AITC-absent environment, indicating that AITC-induced decline in actin-related movements is a reversible process. These findings provide novel insights into the cellular events in plant cells following exposure to AITC, which may further expose clues to the physiological significance of the glucosinolate-myrosinase system.

  7. Allyl functionalized phosphinite and phosphonite ligands: Synthesis, transition metal chemistry and orthopalladation reactions

    Indian Academy of Sciences (India)

    Singappagudem Govindaraju; Guddekoppa S Ananthnag; Susmita Naik; Shaikh M Mobin; Maravanji S Balakrishn

    2012-07-01

    Allyl functionalized phosphinite PPh2(OAr) [Ar=C6H4(-C3H5)] (1) and phosphonite PPh(OAr)2 (2) ligands were prepared by the reactions of 2-allylphenol with PPh2Cl and PPhCl2, respectively. The ruthenium(II) complexes, [Ru(6--cymene)(PPh2(OAr))Cl2] (3) and [Ru(6--cymene)(PPh(OAr)2Cl2)] (4) were obtained by reacting 1 or 2 with [Ru(6--cymene)Cl2]2 in 2:1 molar ratios, respectively. Reactions of 1 or 2 with AuCl(SMe2) gave [Au{PPh2(OAr)}Cl] (5) or [Au{PPh(OAr)2}Cl] (6) in good yield. The palladium complex, [Pd{PPh(OAr)2}2Cl2] (7) was prepared by reacting Pd(COD)Cl2 with 2 in 1:2 molar ratio. The reaction between Pd(COD)Cl2 and 1 yielded a mixture of orthopalladated cis- and trans-[Pd(Ph2P(OAr))Cl]2 (8a and 8b). The treatment of 8 with PPh3 and Ph2PCH2PPh2 resulted in the cleavage of chloro bridge to give respectively, [Ph2(OAr)PPd(PPh3)Cl] (9) and [Ph2(ArO)PPd(2-dppm)]OTf (10). Single crystal X-ray structure of the ruthenium complex 3 is described.

  8. Biosynthesis of archaeal membrane ether lipids.

    Science.gov (United States)

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

    2014-01-01

    A vital function of the cell membrane in all living organism is to maintain the membrane permeability barrier and fluidity. The composition of the phospholipid bilayer is distinct in archaea when compared to bacteria and eukarya. In archaea, isoprenoid hydrocarbon side chains are linked via an ether bond to the sn-glycerol-1-phosphate backbone. In bacteria and eukarya on the other hand, fatty acid side chains are linked via an ester bond to the sn-glycerol-3-phosphate backbone. The polar head groups are globally shared in the three domains of life. The unique membrane lipids of archaea have been implicated not only in the survival and adaptation of the organisms to extreme environments but also to form the basis of the membrane composition of the last universal common ancestor (LUCA). In nature, a diverse range of archaeal lipids is found, the most common are the diether (or archaeol) and the tetraether (or caldarchaeol) lipids that form a monolayer. Variations in chain length, cyclization and other modifications lead to diversification of these lipids. The biosynthesis of these lipids is not yet well understood however progress in the last decade has led to a comprehensive understanding of the biosynthesis of archaeol. This review describes the current knowledge of the biosynthetic pathway of archaeal ether lipids; insights on the stability and robustness of archaeal lipid membranes; and evolutionary aspects of the lipid divide and the LUCA. It examines recent advances made in the field of pathway reconstruction in bacteria. PMID:25505460

  9. Process for producing cyclic ethers from lactones

    International Nuclear Information System (INIS)

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

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

    NARCIS (Netherlands)

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

    2016-01-01

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

  11. CuCl-Catalyzed Aerobic Oxidation of Allylic and Propargylic Alcohols to Aldehydes or Ketones with 1 : 1 Combination of Phenanthroline and Bipyridine as the Ligandst%CuCl-Catalyzed Aerobic Oxidation of Allylic and Propargylic Alcohols to Aldehydes or Ketones with 1 : 1 Combination of Phenanthroline and Bipyridine as the Ligandst

    Institute of Scientific and Technical Information of China (English)

    刘宇; 麻生明

    2012-01-01

    We developed a modified protocol for the oxidation of 2,3-allenyl alcohols using CuCI with l : 1 combination of phenanthroline and bipyridine as the catalyst. To further investigate the applicability of this system, other types of alcohols such as allylic and propargylic alcohols have been tested: we found that both allylic and propargylic alcohols may be oxidized to the corresponding aldehydes or ketones using molecular oxygen in air as the oxidant with moderate to excellent yields.

  12. Study on the Epoxidation of Double Bond in Cardanol Glycidyl Ether Side Chain%腰果酚缩水甘油醚侧链双键的环氧化研究

    Institute of Scientific and Technical Information of China (English)

    陈卫航; 张明伟; 王宏力

    2014-01-01

    以双氧水和冰乙酸为氧化剂,将腰果酚缩水甘油醚的侧链双键氧化成环氧基.以环氧值为主要指标,采用单因素试验探讨了各反应条件对多环氧基腰果酚缩水甘油醚(PEGCGE)环氧值的影响,确定了反应较适宜的工艺条件.采用正交法设计试验得到合成PEGCGE的适宜工艺条件为:n(CGE)∶n(冰乙酸)∶n(双氧水)=1∶1.5∶2.5(摩尔比),m(CGE)∶m(甲苯)∶m(固体酸)=1∶3∶0.5(质量比),最终得到PEGCGE的环氧值为0.601 mol/100 g,收率为89.2%.另外,采用FT-IR和1H-NMR对其结构进行了表征.

  13. Determination method and characterization of the epoxy value of polyepoxy group cardanol glycidyl ether(PEGCGE)%多环氧基腰果酚缩水甘油醚环氧值的测定方法及表征

    Institute of Scientific and Technical Information of China (English)

    周贤国; 武臻; 袁琳; 田倩倩; 王宏力

    2015-01-01

    针对多环氧基腰果酚缩水甘油醚的物化特性,分析对比了光谱分析法、化学分析法、高氯酸-四乙基溴化铵法、盐酸-吡啶法和盐酸-丙酮法等多种环氧值的测定方法,选择了优化改进的盐酸-丙酮法作为产物环氧值的测定方法;并采用红外光谱对多环氧基腰果酚缩水甘油醚、腰果酚缩水甘油醚和腰果酚进行了表征.

  14. Ethylated Urea - Ether - Modified Urea - Formaldehyde Resins,

    Directory of Open Access Journals (Sweden)

    Mathew Obichukwu EDOGA

    2006-07-01

    Full Text Available First, phenol - formaldehyde (PF and urea - formaldehyde (UFII resins were separately conventionally prepared in our laboratory. Also, UF resin synthesized from the acid modified synthesis procedure was synthesized in a purely acid medium of pH 1.0, FU molar ratio of 1.0 and at 50oC (one-stage acid modified-synthesis procedure. Subsequently, the UF resin II was modified during synthesis by incorporating ethylated urea-ether (EUER (i.e. UFIII and glycerol (GLYC (i.e. UFV cured with and without acid curing agent. The structural and physicochemical analyses of the various resin samples were carried out.The results showed that the unmodified UF resin (UF II synthesized in acid medium of pH 1.0, F/U molar ratio 1.0, and at 50oC, cured in absence of acid curing catalyst, showed features in their spectra which are consistent with a tri-, and/or tetra-substituted urea in the reaction to give a 3 - dimensional network cured UF resin. Modification of the UF resin(UF II with ethylated urea-ether and glycerol to produce UF resins III and respectively V prominently increased the absorbance of methylene and ether groups in the spectra which are consistent with increased hydrophobicity and improved hydrolytic stability. For the conventional UF resin (UF I, the only clear distinction between spectra for the UF resin II and UF resins (III/V is the presence of diminished peaks for methylene groups at 2.2 ppm. The relationship between the logarithmic viscosity of cured PF resin with time showed continuos dependence of viscosity with time during cure up to 70 minutes. Similar trends were shown by UF resins (III/V, cured in absence of acid catalyst. In contrast, the conventional UF resins I and UF IV (i.e. UF II cured with NH4CL showed abrupt discontinuity in viscosity with time just after about 20 minutes of cure.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-01-01

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

  16. Polymeric 32-channel arrayed waveguide grating multiplexer using fluorinated poly (ether ether ketone)

    Institute of Scientific and Technical Information of China (English)

    Fei Wang(王菲); Wei Sun(孙伟); Aize Li(李艾泽); Maobin Yi(衣茂斌); Zhenhua Jiang(姜振华); Daming Zhang(张大明)

    2004-01-01

    In wavelength division multiplexing (WDM) systems, an arrayed waveguide grating (AWG) multiplexer is a key component. A polymeric AWG multiplexer has recently attracted much attention due to its low cost processing and a potential of integration with other devices. Fluorinated poly (ether ether ketone)(FPEEK) is excellent material for fabrication of optical waveguides due to its low absorption loss at 1.55-μm wavelength and high thermal stability. A 32-channel AWG multiplexer has been designed based on the grating diffraction theory and fabricated using newly synthesized FPEEK. During the fabrication process of the Polymer/Si AWG device, spin coating, vaporizing, photolithographic patterning and reactive ion etching (RIE) are used. The AWG multiplexer measurement system is based on a tunable semiconductor laser, infrared camera and a Peltier-type heater. The device exhibits a wavelength channel spacing of 0.8nm and a center wavelength of 1548 nm in the room temperature.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-03-01

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

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

    Science.gov (United States)

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

    2016-06-01

    As a promising implantable material, poly ether ether ketone (PEEK) possesses similar elastic modulus to that of cortical bones yet suffers from bio-inertness and poor osteogenic properties, which limits its application as orthopedic implants. In this work, calcium is introduced onto PEEK surface using calcium plasma immersion ion implantation (Ca-PIII). The results obtained from scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) confirm the modified layer with varying contents of calcium are formed on PEEK surfaces. Water contact angle measurements reveal the increasing hydrophobicity of both Ca-PIII treated surfaces. In vitro cell adhesion, viability assay, alkaline phosphatase activity and collagen secretion analyses disclose improved the adhesion, proliferation, and osteo-differentiation of rat bone mesenchymal stem cells (bMSCs) on Ca-PIII treated surfaces. The obtained results indicate that PEEK surface with enhanced osteogenic activity can be produced by calcium incorporation. PMID:26954085

  19. Effects of spinneret structure on poly-ether-ether-ketone fibers by screw extrusion

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xin-ying; YI Xiao-su; XU Zhong-bin; XU Ya-hong

    2005-01-01

    According to the characters of poly-ether-ether-ketone (PEEK) plastic, the spinnerets with three kinds of different structure were designed. The effects of spinneret structure on the melt spinning conditions, melt flow instability of the screw extrusion, and the performance of PEEK fibers were studied. The results show that the appropriate screw extrusion temperature is 370 -385℃. The PEEK fibers extruded using the spinnerets with L/D= 6,8 holes and 0.5 mm in diameter have better performances. The performances of PEEK fibers are related to the diameter of the spinneret hole. Increasing the L/D value of the spinnerets can not always improve the surface quality and the performances of PEEK fibers. The extrusion pressure is about 50% of that of the spinneret with 12 holes and 0.3 mm in diameter.

  20. Hydrophilization of Poly(ether ether ketone) Films by Surface-initiated Atom Transfer Radical Polymerization

    DEFF Research Database (Denmark)

    Fristrup, Charlotte Juel; Eskimergen, Rüya; Burkrinsky, J.T.;

    2008-01-01

    Poly(ether ether ketone) (PEEK) replaces aluminum and other metals in aerospace, electronics, medical, and automotive applications. Therefore, the demand for metallization of PEEK is continuously increasing. Metals seldom bond to a polymer without undergoing some chemical interaction - this is the......-modified PEEK using Surface-Initiated Atom Transfer Radical Polymerization (SI ATRP). Surface reduction of PEEK to form hydroxyl groups [1, 2, 3] was .performed prior to the attachment of 2-bromoisobutyrate initiating groups. Each modification step of PEEK as well as the polymer grafting was followed and...... mechanism leading to good adhesion. From the different types of bonding, the covalent bond at the polymer - metal interface is the strongest. In this work the surface ofPEEK is functionalized by covalently bounding of hydrophilic polymer brushes ofpoly(ethyleneglycol) methacrylate (PEGMA) from initiator...

  1. Modification of Poly(ether ether ketone Polymer for Fuel Cell Application

    Directory of Open Access Journals (Sweden)

    Devesh Shukla

    2013-01-01

    Full Text Available Polyelectrolyte membrane (PEM is an important part of PEM fuel cell. Nafion is a commercially known membrane which gives the satisfactory result in PEM fuel cell operating at low temperature. Present research paper includes functionalization of Poly(ether ether ketone (PEEK polymer with phosphonic acid group. The functionalization was done with the help of nickel-based catalyst. Further, the polymer was characterized by the FTIR, EDAX, DSC, TGA, and 1H NMR, and it was found that PEEK polymer was functionalized with phosphonic acid group with good thermal stability in comparison to virgin PEEK. Finally, the thin films of functionalized polymer were prepared by solution casting method, and proton conductivity of film samples was measured by impedance spectra whose value was found satisfactory with good thermal stability in comparison to commercially available Nafion membrane.

  2. Immobilization of invertase and glucoamylase on a macroporous copolymer of etyleneglycoldimethacrylate and glycidyl methacrylate and potential applications in biotechnology

    Directory of Open Access Journals (Sweden)

    Prodanović Radivoje M.

    2003-01-01

    Full Text Available The optimal conditions for the immobilization of invertase and glucoamylasewere found via their carbohydrate moiety on a macroporous copolymer of ehtyleneglycoldimethacry late and glycidylmethacrylate. Almost all of the added enzyme was bound to the polymer by increasing the time of incubation of the oxidized enzyme with polymer. A specific activity of 5500 U/g for invertase was obtained and 1100 U/g for glucoamylase. The specific productivity for invertase in a packed bed reactor was 3.5 kg/lh and for glucoamylase 1.9 kg/lh. During continuous use in a packed bed the reactor operational half life for invertase was 290 days, while no decrease in activity was observed for glucoamylase. In 50% (v/v ethanol the immobilized enzymes were five to ten times more stable, and more than 200 times more stable in 25% (v/v dioxane. The immobilized enzymes retained all activity in petroleum ether after 3 days of incubation. Because of their higher stability over native enzymes, and the large surface area of the polymer immobilized glucoamylase and invertase could be more useful for glycoside synthesis in non-aqueous solvents than native ones.

  3. Magnetic poly(glycidyl methacrylate)-based microspheres prepared by suspension polymerization in the presence of modified La0.75Sr0.25MnO3 nanoparticles

    Czech Academy of Sciences Publication Activity Database

    Horák, Daniel; Pollert, Emil; Trchová, Miroslava; Kovářová, Jana

    2009-01-01

    Roč. 45, č. 4 (2009), s. 1009-1016. ISSN 0014-3057 R&D Projects: GA AV ČR 1QS100100553; GA AV ČR KAN200200651 Institutional research plan: CEZ:AV0Z40500505; CEZ:AV0Z10100521; CEZ:AV0Z1010921 Keywords : glycidyl methacrylate * perovskite * magnetic Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.310, year: 2009

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-02-15

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

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

    Highlights: • PEEK-g-PVBSA, a polymer electrolyte membrane was prepared by a radiation grafting technique. • Poly(ether ether ketone) (PEEK), an aromatic hydrocarbon polymer was used as a grafting backbone film. • The water uptake, proton conductivity, and methanol permeability of the membranes were evaluated. • PEEK-g-PVBSA membranes show considerably lower methanol permeability compared to a Nafion membrane. -- Abstract: In this study, an aromatic hydrocarbon based polymer electrolyte membrane, poly(vinylbenzyl sulfonic acid)-grafted poly(ether ether ketone) (PEEK-g-PVBSA), has been prepared by the simultaneous irradiation grafting of vinylbenzyl chloride (VBC) monomer onto a PEEK film and subsequent sulfonation. Each chemical conversion was monitored by FT-IR and SEM–EDX instruments. The physicochemical properties including IEC, water uptake, proton conductivity, and methanol permeability of the prepared membranes were also investigated and found that the values of these properties increase with the increase of degree of grafting. It was observed that the IEC values of the prepared PEEK-g-PVBSA membranes with 32%, 58%, and 80% DOG values were 0.50, 1.05, and 1.22 meq/g while the water uptakes were 14%, 20%, and 21%, respectively. The proton conductivities (0.0272–0.0721 S/cm at 70 °C) were found to be somewhat lower than Nafion 212 (0.126 S/cm at 70 °C) at a relative humidity of 90%. However, the prepared membranes showed a considerably lower methanol permeability (0.61–1.92 × 10−7 cm2/s) compared to a Nafion 212 membrane (5.37 × 10−7 cm2/s)

  7. Microwave Spectrum of the Ethylmethyl Ether Molecule

    Directory of Open Access Journals (Sweden)

    Kojiro Takagi

    2003-01-01

    Full Text Available We have observed rotational transitions of ethylmethyl ether (CH3CH2OCH3 in the 24-110 GHz frequency range. We newly assigned the transitions of four Q-branch series for J=1-38 with Ka=0-5 and six R-branch series of b-type transitions for J=7-37 with Ka=0-3. All these assigned transitions were observed to be split into two or four components due to the internal rotations of the methyl groups. We analyzed the averaged frequencies of the split components on the basis of the Watson A-reduced Hamiltonian, neglecting the effect of the internal rotations. A total of 122 transitions were fitted to eight molecular parameters to a 1s standard deviation of 24 kHz. The parameters A, B, C and DJ were improved, and DJK, Dk, dJ and dK were determined for the first time.

  8. The Lubrication Qualities of Dimethyl Ether (DME)

    DEFF Research Database (Denmark)

    Sivebæk, Ion Marius; Sorenson, Spencer C; Jakobsen, J.

    2002-01-01

    Dimethyl Ether (DME) has been recognised as a clean alternative for diesel oil for some years now. Fuelling diesel engines with DME solves their two most significant problems: The emission of particulate matter is virtually eliminated and the level of NOx can be reduced considerably by exhaust gas...... the viscosity, which plays a major role in the hydrodynamic lubrication regime. The lubricity of DME has been established by the medium frequency pressurised reciprocating rig (MFPRR) to be very low compared to the one of diesel oil. But the DME film limits the wear extent significantly compared to...... the case of dry sliding. By mixing DME with additives, the lubricity level is easily raised even above the one of diesel oil. The viscosity of DME has been established by the volatile fuel viscometer (VFVM) to be as low as 0.185 cSt @ 25 oC. It is also shown that this viscosity cannot be raised...

  9. Acyclic archaebacterial ether lipids in swamp sediments

    Science.gov (United States)

    Pauly, George G.; Van Vleet, Edward S.

    1986-06-01

    Acyclic phytanyl diether glycerol and biphytanyl ether lipids have been quantified in two modern swamp sediment cores in concentrations ranging up to 360 μg/ml porewater. Methanogenic bacteria are the only known source organisms which can inhabit the swamp sediments. Variations in relative abundance between these lipids may reflect taxonomic changes in methanogen populations or the stage of growth. Maxima in methanogen lipid concentrations coincide with local maxima of 13C of organic matter, possibly the result of a pool effect on CO 2 or acetate. Methane production estimates calculated from lipid concentrations in swamp sediments range from 0.1 to 1.3 mmol cm -2 yr -1, values which are consistent with published methane fluxes.

  10. Development of specialty chemicals from dimethyl ether

    Energy Technology Data Exchange (ETDEWEB)

    Tartamella, T.L.; Lee, S. [Univ. of Akron, OH (United States). Dept. of Chemical Engineering

    1996-12-31

    Dimethyl ether (DME) may be efficiently produced from coal-bases syngas in a high pressure, mechanically agitated slurry reactor. DME synthesis occurs in the liquid phase using a dual catalyst. By operating in a dual catalyst mode, DME may be converted from in-situ produced methanol resulting in higher methyl productivities and syngas conversions over methanol conversion alone. The feasibility of utilizing DME as a building block for more valuable specialty chemicals has been examined. A wide variety of petrochemicals may be produced from DME including light olefins, gasoline range hydrocarbons, oxygenates, and glycol precursors. These chemicals represent an important part of petroleum industries inventory of fine chemicals. Carbonylation, hydrocarbonylation, and oxidative dimerization are but a few of the reactions in which DME may undergo conversion. DME provides an additional route for the production of industrially important petrochemicals.

  11. Formulating liquid ethers for microtubular SOFCs

    Science.gov (United States)

    Kendall, Kevin; Slinn, Matthew; Preece, John

    One of the key problems of applying solid oxide fuel cells (SOFCs) in transportation is that conventional fuels like kerosene and diesel do not operate directly in SOFCs without prereforming to hydrogen and carbon monoxide which can be handled by the nickel cermet anode. SOFCs can internally reform certain hydrocarbon molecules such as methanol and methane. However, other liquid fuels usable in petrol or diesel internal combustion engines (ICEs) have not easily been reformable directly on the anode. This paper describes a search for liquid fuels which can be mixed with petrol or diesel and also injected directly into an SOFC without destroying the nickel anode. When fuel molecules such as octane are injected onto the conventional nickel/yttria stabilised zirconia (Ni/YSZ) SOFC fuel electrode, the anode rapidly becomes blocked by carbon deposition and the cell power drops to near zero in minutes. This degeneration of the anode can be inhibited by injection of air or water into the anode or by some upstream reforming just before entry to the SOFC. Some smaller molecules such as methane, methanol and methanoic acid produce a slight tendency to carbon deposition but not sufficient to prevent long term operation. In this project we have investigated a large number of molecules and now found that some liquid ethers do not significantly damage the anode when directly injected. These molecules and formulations with other components have been evaluated in this study. The theory put forward in this paper is that carbon-carbon bonds in the fuel are the main reason for anode damage. By testing a number of fuels without such bonds, particularly liquid ethers such as methyl formate and dimethoxy methane, it has been shown that SOFCs can run without substantial carbon formation. The proposal is that conventional fuels can be doped with these molecules to allow hybrid operation of an ICE/SOFC device.

  12. N-allyl epiderpride: An extremely potent SPECT radioligand for the dopamine D2 receptor

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, R.M.; Mason, N.S.; Ansari, M.S. [Vanderbilt Univ., Nashville, TN (United States)] [and others

    1994-05-01

    We have previously reported that epidepride is a potent (K{sub D} 24pM) and specific SPECT radioligand for the dopamine D2 receptor which can be used to study striatal and extrastriatal dopamine D2 receptors in man. We have synthesized and evaluated the N-allyl analogue of epiderpride (APID) as a potential SPECT radioligand for the dopamine D2 receptor. In comparison to epidepride it is even more potent at the dopamine D2 receptor, the K{sub D} for APID being 11 frontal cortical homogenate. The lipophilicity, evaluated using the log kw pH 7.5, was 2.9 versus 2.05 for epidepride. Competitive binding studies using rat striatal, hippocampal and frontal cortical homogenates showed high affinity for only dopamine D2 like cerebellar ratio of 275:1 at 320 minutes post injection-similar to that seen with epidepride, but with nearly four times higher brain uptake. Of interest was the off-rate from the dopamine D2 receptor; it was 0.0046 min{sup -1} in vitro at 25{degrees}C-corresponding to an t 1/2 of 150 minutes. Studies in rhesus monkeys show an in vivo off rate (following 2.5 mg/kg raclopride IV) of about 0.0082 min{sup -1} seen that with epidepride. SPECT studies in rhesus monkeys reveal APID is a promising SPECT radioligand that appears to be similar to epidepride, but with higher brain uptake due to its more optimal lipophilicity for entry into brain.

  13. Antibacterial activity of starch/acrylamide/allyl triphenyl phosphonium bromide copolymers synthesized by gamma irradiation

    International Nuclear Information System (INIS)

    Starch/acrylamide/allyl triphenyl phosphonium bromide (St/AM/TP) copolymers were synthesized by simultaneous gamma irradiation and characterized by FTIR and 1H NMR techniques, weight measurement and titration method. Moreover, their antibacterial activities against Staphylococcus aureus were explored by the viable cell counting method in sterile distilled water. At St/AM/TP 6:8.4:5.6 g, copolymers with higher graft ratio (G) and higher (AM+TP) graft efficiency (EAM+TP) were obtained at 3 and 6 kGy, while cationic degree (CD) and TP graft efficiency (ETP) continuously increased with absorbed dose from 1 to 6 kGy. All of the copolymers were capable of killing >99.75% of 107 CFU/ml S. aureus within 30 mins. Moreover, at 3 kGy, G, EAM+TP and ETP increased with AM/TP from 0:14 to 11.2:2.8 g at St/(AM+TP) 6:14 g, while the optimum CD and antibacterial activity were achieved at AM/TP 7:7 and 8.4:5.6 g. In addition, at 3 kGy, G, EAM+TP and CD increased with St/(AM+TP) from 6:3 to 6:18 g at AM/TP 8.4:5.6 g, while the optimum antibacterial activity was achieved at 6:10 to 6:18 g, and the optimum ETP was achieved at 6:14. - Highlights: • Cationic starch is prepared from AM and TP by Gamma irradiation. • Cationic starch is characterized by FTIR, NMR, weight method and titration method. • Grafting ratio and cationic degree depend on absorbed dose and composition. • Cationic starch shows good antibacterial activity against Staphylococcus aureus

  14. Does 1-Allyl-3-methylimidazolium chloride Act as a Biocompatible Solvent for Stem Bromelain?

    Science.gov (United States)

    Jha, Indrani; Bisht, Meena; Venkatesu, Pannuru

    2016-06-30

    The broader scope of ILs in chemical sciences particularly in pharmaceutical, bioanalytical and many more applications is increasing day by day. Hitherto, a very less amount of research is available in the depiction of conformational stability, activity, and thermal stability of enzymes in the presence of ILs. In the present study, the perturbation in the structure, stability, and activity of stem bromelain (BM) has been observed in the presence of 1-allyl-3-methylimidazolium chloride ([Amim][Cl]) using various techniques. This is the first report in which the influence of [Amim][Cl] has been studied on the enzyme BM. Fluorescence spectroscopy has been utilized to map out the changes in the environment around tryptophan (Trp) residues of BM and also to discuss the variations in the thermal stability of BM as an outcome of its interaction with the IL at different concentrations. Further, the work delineates the denaturing effect of high concentration of IL on enzyme structure and activity. It dictates the fact that low concentrations (0.01-0.10 M) of [Amim][Cl] are only changing the structural arrangement of the protein without having harsh consequences on its activity and stability. However, high concentrations of IL proved to be totally devastating for both activity and stability of BM. The observed decrease in the stability of BM at high concentration may be due to the combined effect of cation and anion interactions with the protein residues. The present work is successful in dictating the probable mechanism of interaction between BM and [Amim][Cl]. These results can prove to be fruitful in the studies of enzymes in aqueous IL systems since the used IL is thermally stable and nonvolatile in nature thereby providing a pathway of alteration in the activity of enzymes in potentially green systems. PMID:27268069

  15. New copolymer of acrylamide with allyl methacrylate and its capacity for the removal of azo dyes

    Directory of Open Access Journals (Sweden)

    Yeliz Yildirim

    2015-04-01

    Full Text Available The copolymerization reactions of Acrylamide (AA with the different mole ratios of allyl methacrylate (AMA such as 25/75, 50/50 and 75/25 were studied by radical polymerization under argon atmosphere using 2,2’-Azobis (isobutyronitri1e (AIBN as initiator. The copolymers were characterized with Fourier transform infrared spectroscopy (FTIR and thermogravimetric analysis (TG. FTIR spectra showed that the C=O, C-N and N-H groups in copolymers remained during the copolymerization. It is concluded from the thermograms that Poly(AA-co-AMA copolymers which contained different ratios of monomer and comonomer exhibit similar thermal behavior. Adsorption capacity, kinetic and isotherm studies of Direct Brown 2 onto the copolymers have been evaluated. Different factors such as the monomer ratio, pH, initial dye concentration, copolymer dosage and contact time affecting the removal process were studied. It was found that the adsorption process agreed with the Freundlich and Dubinin-Raduskevich model and the adsorption of Direct Brown 2 depended on the acrylamide content and pH of the solution. The standard Gibb’s free energy was determined as - 14.7 kJ/mol, which means that adsorption occurred spontaneously and the process is feasible. Increasing the acrylamide content led to increased adsorption of Direct Brown 2 on the copolymer. Moreover, adsorption kinetic studies showed that the adsorption followed a pseudo-second-order kinetic model, indicating that the chemical adsorption was the rate-limiting step. These results show that Poly(AA-co-AMA can be used as adsorbent for water pollutants such as Direct Brown 2 and has potential applications in related industrial and environmental areas.

  16. S-Allyl-Cysteines Reduce Amelioration of Aluminum Induced Toxicity in Rats

    Directory of Open Access Journals (Sweden)

    Sadhana Shrivastava

    2011-01-01

    Full Text Available Problem statement: Aluminum (Al is a trivalent cation found in its ionic form in most kinds of animal tissues and in natural waters everywhere. Approach: It is a potent neurotoxin and has been associated in the pathogenesis of several clinical disorders including Alzheimer’s disease. Results: The aim of the study was to demonstrate the protective effect of S-Allyl-Cysteines (SAC against Al-induced toxicity in rat model on certain biochemical parameters, lipid peroxidation and oxidative stress enzymes of white albino rats. Six rats per group were divided into various treatment groups. Group one rats were given normal saline and served as control group. Group two animals received Al as aluminum nitrate 32.5 mg (i.p. for the induction of toxicity. Group three to five received different doses of SAC (25, 50 and 100 mg kg-1 for 3 days after 24 h of Al toxicity. Rats were orally administered their respective doses every day for 3 days. Evaluations were made in blood and tissues. The activity of Acetylcholinesterase (AchE was inhibited in all the parts of brain after Al intoxication. Significant rise were observed the Activities of Serum Transaminases (AST and ALT after toxicant exposure. The activity of â-Aminolevulinic acid Dehydratase (ALAD in blood and â-Aminolevulinic Acid Synthetase (ALAS in brain was decreased after Al exposure. Al significant increased cholesterol, triglyceride, creatinine and urea level in serum. TBARS level was significantly higher and GSH content were significantly lower during toxicity. Total and esterified cholesterol in liver, kidney and brain were increased after Al exposure. Histopathological changes in liver, kidney and brain were also recouped with the therapy. Conclusion/Recommendations: Our data proved that SAC which is a bioactive and bioavailable component of garlic has organosulfur compounds which regulates the thiol status of the cell and scavenges free radicals and work as an antioxidant. Thus SAC

  17. Synthesis and Adsorption Property of Dihydroxyl Azacrown Ether-Grafted Chitosan

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A novel dihydroxyl azacrown ether chitosan was synthesized by reacting dihydroxyl azacrown ether with epoxy activated chitosan. The adsorption property of the azacrown ether chitosan for Pb2+, Cr3+, and Ag+, were determined. The experimental results showed that the dihydroxyl azacrown ether grafted chitosan has high adsorption capacity and high selectivity for some metal ions.

  18. Allyl- iso-propyltelluride, a new MOVPE precursor for CdTe, HgTe and (Hg,Cd)Te

    Science.gov (United States)

    Hails, Janet E.; Cole-Hamilton, David J.; Stevenson, John; Bell, William

    2000-06-01

    The use of allyl- iso-propyltelluride as the tellurium precursor for the growth of CdTe, HgTe and (Hg,Cd)Te by metal organic vapour-phase epitaxy has been investigated. It has proved to be an efficient source of tellurium with growth rates for HgTe and (Hg,Cd)Te of up to 10 μm h -1 at 300°C. The best CdTe was grown at 4.5 μm h -1 under Me 2Cd-rich conditions at 300°C in the presence of Hg vapour.

  19. Copper-catalysed asymmetric allylic alkylation of alkylzirconocenes to racemic 3,6-dihydro-2H-pyrans

    Science.gov (United States)

    Rideau, Emeline

    2015-01-01

    Summary Asymmetric allylic alkylation is a powerful reaction that allows the enantioselective formation of C–C bonds. Here we describe the asymmetric alkylation of alkylzirconium species to racemic 3,6-dihydro-2H-pyrans. Two systems were examined: 3-chloro-3,6-dihydro-2H-pyran using linear optimization (45–93% ee, up to 33% yield, 5 examples) and 3,6-dihydro-2H-pyran-3-yl diethyl phosphate with the assistance of a design of experiments statistical approach (83% ee, 12% yield). 1H NMR spectroscopy was used to gain insight into the reaction mechanisms. PMID:26734091

  20. Synthesis and characterization of 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) and structurally related compounds evidenced in seal blubber and brain.

    Science.gov (United States)

    von der Recke, Roland; Vetter, Walter

    2007-03-01

    The unknown compound UBC-1 previously described as the major organobromine contamination in the blubber extract of a hooded seal (Cystophora cristata) from the Barents Sea was identified as 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE). DPTE, which is the main component of the brominated flame retardant (BFR) Bromkal 73-5 PE, was synthesized by electrophilic addition of bromine to allyl-2,4,6-tribromophenyl ether (ATE). The chirality of DPTE was proven by gas chromatographic enantioseparation of the synthesized racemate. On the basis of GC/ECNI-MS ion chromatograms (m/z79 and 81), DPTE was the dominating organobromine compound in blubber and brain samples of hooded seals and harp seals (Phoca groenlandica) from the Barents and Greenland Seas. The concentrations of DPTE in blubber and brain were up to 470 and 340 microg/kg wet weight. Next to DPTE, the natural dibromo-trichloromonoterpene (MHC-1), the anthropogenic BDE 47 and BDE 99, as well as ATE, 3,5-dibromo-2-(2',4'-dibromo)-phenoxyanisole (6-MeO-BDE 47), 2-bromoallyl-2,4,6-tribromophenyl ether (BATE), and 4,6-dibromo-2-(2',4'-dibromo)-phenoxyanisole (2'-MeO-BDE 68) were present with decreasing relevance. BATE, which was detected for the first time in environmental samples, was synthesized from DPTE by E2 elimination. In brain samples of the harp seals, DPTE, ATE, and BATE were the most abundant organobromine compounds, whereas polybrominated diphenyl ethers (PBDEs) and MHC-1 were virtually absent. This indicated that DPTE, ATE, and BATE were able to penetrate the blood-brain barrier. The general co-occurrence of ATE and BATE in samples contaminated with DPTE support the hypothesis that these compounds are biotransformation products of DPTE. Anaerobic transformation studies of DPTE with super-reduced corrinoids resulted in the formation of ATE. Furthermore, 2,4,6-tribromophenol (TBP) and two other unknown minor transformation products were detected. PMID:17396646

  1. Functionalized macroporous copolymer of glycidyl methacrylate: The type of ligand and porosity parameters influence on Cu(II ion sorption from aqueous solutions

    Directory of Open Access Journals (Sweden)

    Sandić Zvjezdana P.

    2009-01-01

    Full Text Available The removal of heavy metals from hydro-metallurgical and other industries' wastewaters, their safe storage and possible recovery from waste- water streams is one of the greater ecological problems of modern society. Conventional methods, like precipitation, adsorption and biosorption, electrowinning, membrane separation, solvent extraction and ion exchange are often ineffective, expensive and can generate secondary pollution. On the other hand, chelating polymers, consisting of crosslinked copolymers as a solid support and functional group (ligand, are capable of selectively loading different metal ions from aqueous solutions. In the relatively simple process, the chelating copolymer is contacted with the contaminated solution, loaded with metal ions, and stripped with the appropriate eluent. Important properties of chelating polymers are high capacity, high selectivity and fast kinetics combined with mechanical stability and chemical inertness. Macroporous hydrophilic copolymers of glycidyl methacrylate and ethylene glycol dimethacrylate modified by different amines show outstanding efficiency and selectivity for the sorption of precious and heavy metals from aqueous solutions. In this study poly(GMA-co-EGDMA copolymers were synthesized with different porosity parameters and functionalized in reactions with ethylene diamine (EDA, diethylene triamine (DETA and triethylene tetramine (TETA. Under non-competitive conditions, in batch experiments at room temperature, the rate of sorption of Cu(II ions from aqueous solutions and the influence of pH on it was determined for four samples of amino-functionalized poly(GMA-co-EGDMA. The sorption of Cu(II for both amino-functionalized samples was found to be very rapid. The sorption half time, t1/2, defined as the time required to reach 50% of the total sorption capacity, was between 1 and 2 min. The maximum sorption capacity for copper (2.80 mmol/g was obtained on SGE-10/12-deta sample. The sorption

  2. 烯丙基苯并恶嗪改性BT树脂的研究%Study on Bismaleimide-Triazine Resin Modiifed by Allyl Benzoxazine

    Institute of Scientific and Technical Information of China (English)

    陈虹; 寇开昌; 王益群; 张宇; 卓龙海

    2014-01-01

    采用熔融缩聚法合成了烯丙基苯并恶嗪(Boz-allyl),并利用傅立叶变换红外光谱,磁共振氢谱对其表征。用动态扫描量热与热重分析研究了其固化过程及热性能,随后用其对双马来酰亚胺-三嗪树脂(BT树脂)改性,并分析了改性树脂的力学性能。结果表明,Boz-allyl存在两种固化机理,固化物5%和10%热失重温度分别为325,385℃,在800℃时质量保持率仍可达34%,说明其具有优良的热稳定性和耐烧蚀性,用其改性后BT树脂韧性明显提高,当Boz-allyl质量分数为8%时冲击和弯曲强度达到最大值,分别为11.32 kJ/m2和127.11 MPa。%An allyl benzoxazine(Boz-allyl) was synthesized by melt polycondensation method and the structures of Boz-allyl was confirmed by Fourier transform infrared spectroscopy and nuclear magnetic resonance. Using differential scanning calorimetery and thermal gravimetric analysis,the curing behavior and thermal property of it were probed. Then the bismaleimide-triazine resin modified by Boz-allyl was prepared and its mechanical properties was investigated. The results show a dual cure pattern of Boz-allyl ,while the 5%and 10%weight loss temperatures of polybenzoxazine is 325℃and 385℃respectively,with quality retention rate up to 34%at 800℃,which reveals good heat resistance and ablation resistance. The addition of Boz-allyl into BT resin significantly improves toughness and strength,its impact strength and flexural strength is up to their maximums of 11.32 kJ/m2 and 127.11 MPa when the mass fraction of Boz-allyl is 8%.

  3. Synthesis of N-Aryl-2-allyl Pyrrolidines via Palladium-catalyzed Carboamination Reactions of γ-(N-Arylamino)alkenes with Vinyl Bromides

    OpenAIRE

    Ney, Joshua E.; Hay, Michael B.; Yang, Qifei; Wolfe, John P.

    2005-01-01

    A palladium-catalyzed carboamination reaction of γ-N-arylamino alkenes with vinyl bromides that affords N-aryl-2-allyl pyrrolidines is described. These reactions proceed with high diastereoselectivity for the formation of trans-2,3- and cis-2,5-disubstituted pyrrolidines. Conditions for a tandem N-arylation/carboamination sequence that leads to the formation of an N-aryl-2-allyl pyrrolidine or indoline via the coupling of a primary γ-amino alkene, an aryl bromide, and a vinyl bromide are also...

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

    Data.gov (United States)

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

  5. The complicated ethers of glycerin and its functional derivatives

    International Nuclear Information System (INIS)

    The glycerides are complicated ethers of glycerin and fat acids. The glycerides call on incoming in their mixture remains of acids. The glycerides formed by palmitic acid have the name-palmitin, by stearine acids-stearins and etc

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

    Directory of Open Access Journals (Sweden)

    V. Gaina

    2013-07-01

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

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

    Directory of Open Access Journals (Sweden)

    Gibran da Cunha Vasconcelos

    2010-08-01

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

  8. Marine Sponge Dysidea herbacea revisited: Another Brominated Diphenyl Ether

    Directory of Open Access Journals (Sweden)

    Bruce F. Bowden

    2005-03-01

    Full Text Available Abstract: A pentabrominated phenolic diphenyl ether (1 that has not previously been reported from marine sources has been isolated from Dysidea herbacea collected at Pelorus Island, Great Barrier Reef, Australia. The structure was determined by comparison of NMR data with those of known structurally-related metabolites. NMR spectral assignments for (1 are discussed in context with those of three previously reported isomeric pentabrominated phenolic diphenyl ethers.

  9. Interpretation of the supraluminous neutrinos by a theory of ether

    OpenAIRE

    Delort, Thierry

    2011-01-01

    We exposed between the years 2000 to 2011 a very general theory of Ether, giving an interpretation of all the main experiments connected to Special and General Relativity and Cosmology. This theory of Ether was most of time even not considered, because it was contrary to Special Relativity. But a French team of physicists (led by Dario Autiero) recently realized an experiment, whose the result was contrary to Special Relativity, because it implied that a particle could go faster that the ligh...

  10. Interpretation of the Opera's experiment by a Theory of ether

    OpenAIRE

    Delort, Thierry

    2011-01-01

    5 pages We exposed between the years 2000 to 2011 a very general theory of Ether, giving an interpretation of all the main experiments connected to Special and General Relativity and Cosmology. This theory of Ether was most of time even not considered, because it was contrary to Special Relativity. But a French team of physicists (led by Dario Autiero) recently realized an experiment (Opera's experiment), whose the result was contrary to Special Relativity, because it implied that a partic...

  11. Highly efficient palladium-catalyzed hydrostannation of ethyl ethynyl ether

    OpenAIRE

    Andrews, Ian P.; Kwon, Ohyun

    2008-01-01

    The palladium-catalyzed hydrostannation of acetylenes is widely exploited in organic synthesis as a means of forming vinyl stannanes for use in palladium-catalyzed cross-coupling reactions. Application of this methodology to ethyl ethynyl ether results in an enol ether that is challenging to isolate from the crude reaction mixture because of incompatibility with typical silica gel chromatography. Reported here is a highly efficient procedure for the palladium-catalyzed hydrostannation of ethy...

  12. Effects of the ether phospholipid AMG-PC on mast cells are similar to that of the ether lipid AMG but different from that of the analogue hexadecylphosphocholine

    DEFF Research Database (Denmark)

    Grosman, Nina

    Farmakologi, ether phospholipid, hexacylphosphocholine, miltefosine, protein kinase C, AMG-PC(alkyl-methyl-glycero-phosphocholine), Histamine release, mast cell......Farmakologi, ether phospholipid, hexacylphosphocholine, miltefosine, protein kinase C, AMG-PC(alkyl-methyl-glycero-phosphocholine), Histamine release, mast cell...

  13. Allyl thiourea as a corrosion inhibitor for cold rolled steel in H{sub 3}PO{sub 4} solution

    Energy Technology Data Exchange (ETDEWEB)

    Li Xianghong, E-mail: xianghong-li@163.com [Faculty of Science, Southwest Forestry University, Kunming 650224 (China) and Key Laboratory for Forest Resources Conservation and Use in the Southwest Mountains of China Ministry of Education, Southwest Forestry University, Kunming 650224 (China); Deng Shuduan [Faculty of Materials Engineering, Southwest Forestry University, Kunming 650224 (China); Fu Hui [Faculty of Science, Southwest Forestry University, Kunming 650224 (China)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer Allyl thiourea (ATU) acts as a good inhibitor for steel in 1.0 M H{sub 3}PO{sub 4}. Black-Right-Pointing-Pointer Inhibition efficiency increases slightly with the temperature at 0.2-0.5 mM. Black-Right-Pointing-Pointer The adsorption of ATU on steel surface obeys Langmuir adsorption isotherm. Black-Right-Pointing-Pointer ATU behaves as a mixed-type inhibitor. - Abstract: The inhibition effect of allyl thiourea (ATU) on the corrosion of cold rolled steel (CRS) in 1.0 M H{sub 3}PO{sub 4} solution at 20-50 Degree-Sign C was studied by weight loss, potentiodynamic polarisation, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) methods. The results show that ATU is a good inhibitor, and the maximum inhibition efficiency of 0.5 mM inhibitor is higher than 95% at all studied temperatures. The adsorption of ATU obeys Langmuir adsorption isotherm. Polarisation curves show that ATU behaves as a mixed-type inhibitor. EIS spectra exhibit one capacitive loop. The inhibition action is also evidenced by SEM.

  14. UV RADIATION INDUCED GRAFT COPOLYMERIZATION OF ALLYL ACETATE ONTO POLY(ETHYLENE TEREPHTHALATE) (PET) FILMS FOR FUEL CELL MEMBRANES

    Institute of Scientific and Technical Information of China (English)

    Mostak Ahmed; Mubarak A. Khan; Nazia Rahman; M. Anwar H. Khan

    2012-01-01

    Ultraviolet (UV)-induced graft copolymerization of allyl acetate (AA) monomer onto poly(ethylene terephthalate) (PET) films and the subsequent sulfonation on the monomer units in the grafting chain using chlorosulfonic acid (C1SO3H) were carried out to prepare proton exchange membranes (PEMs) for fuel cells.A maximum grafting value of 12.8% was found for 35 vol% allyl acetate after 3 h radiation time.Optimum concentration of ClSO3H was selected for the sulfonation reaction to be 0.05 mol/L based on the degree of sulfonation and the tensile strength studies of the membrane.The degree of sulfonation increased as the sulfonation reaction temperature and sulfonation time were increasing.The radiation grafting and the sulfonation have been confirmed by titrimetric and gravimetric analyses as well as FTIR spectroscopy.The maximum ion exchange capacity (IEC) of 0.04125 mmol g-1 was found at 12.1% degree of sulfonation and the maximum proton conductivity was found to be 0.035 S cm-1 at 30℃ and a relative humidity of 60%.The various physical and chemical properties of the PEMs such as water uptake,mechanical strength,thermal durability and oxidative stability were also studied.To investigate the suitability of the prepared membrane for fuel cell applications,its properties were compared with those of Nation 117.

  15. Molecular detection and in vitro antioxidant activity of S-allyl-L-cysteine (SAC) extracted from Allium sativum.

    Science.gov (United States)

    Sun, Y-E; Wang, W-D

    2016-01-01

    It is well known that Allium sativum has potential applications to clinical treatment of various cancers due to its remarkable ability in eliminating free radicals and increasing metabolism. An allyl-substituted cysteine derivative - S-allyl-L-cysteine (SAC) was separated and identified from Allium sativum. The extracted SAC was reacted with 1-pyrenemethanol to obtain pyrene-labelled SAC (Py-SAC) to give SAC fluorescence properties. Molecular detection of Py-SAC was conducted by steady-state fluorescence spectroscopy and time-resolved fluorescence method to quantitatively measure concentrations of Py-SAC solutions. The ability of removing 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radical using Py-SAC was determined through oxygen radical absorbance capacity (ORAC). Results showed the activity of Py-SAC and Vitamin C (VC) with ORAC as index, the concentrations of Py-SAC and VC were 58.43 mg/L and 5.72 mg/L respectively to scavenge DPPH, and 8.16 mg/L and 1.67 mg/L to scavenge •OH respectively. Compared with VC, the clearance rates of Py-SAC to scavenge DPPH were much higher, Py-SAC could inhibit hydroxyl radical. The ability of removing radical showed a dose-dependent relationship within the scope of the drug concentration. PMID:27453278

  16. A local-ether model of propagation of electromagnetic wave

    International Nuclear Information System (INIS)

    It is pointed out that the classical propagation model can be in accord with the Sagnac effect due to earth's rotational and orbital motions in the high-precision GPS (global positioning system) and interplanetary radar, if the reference frame of the classical propagation medium is endowed with a switchability according to the location of the wave. Accordingly, it is postulated that, as in the obsolete theory, electromagnetic waves propagate via a medium like the ether. However, the ether is not universal. It is proposed that in the region under sufficient influence of the gravity due to the earth, the sun, or another celestial body, there forms a local ether, which in turn is stationary with respect to the gravitational potential of the respective body. For earthbound and interplanetary propagation, the medium is stationary in a geocentric and a heliocentric inertial frame, respectively. An electromagnetic wave propagates at a constant speed with respect to the associated local ether, independent of the motions of source and receiver. Based on this local-ether model of wave propagation, a wide variety of earthbound, interplanetary, and interstellar propagation phenomena are accounted for. Strong evidence of this new classical model is its consistent account of the Sagnac effect due to earth's motions among GPS, the intercontinental microwave link, and the interplanetary radar. Moreover, as examined within the present precision, this model is still in accord with the Michelson-Morley experiment. To test the local-ether propagation model, a one-way-link rotor experiment is proposed. (orig.)

  17. Adsorption of rare earths with crown ether adsorbents

    International Nuclear Information System (INIS)

    Crown ether - phosphotungstic acid (PW) and crown ether -phosphomolybdic acid (PMo) precipitates, and also the granular entrapped crown ether - PMo (or PW) in polyacrylamide, were prepared and applied as adsorbents for rare earth metal ions. Adsorbents containing 15-crown-5, such as 15-crown-5 - PMo, were better adsorbents than the other crown ether precipitates. The adsorption capacity of 15-crown-5 - PMo for Eu3+ was determined and corresponded to about 0.166 mmol of Eu3+ per gram of the absorbent. The effects of pH and metal ion concentration on adsorption were also investigated. Crown ether - PMo (or PW) precipitates underwent hydrolysis at pH >= 1, but the granular entrapped crown ether - PMo (or PW) - polyacrylamide adsorbents were not hydrolysed at pH >= 1. The adsorption of individual rare earth ions with 15-crown-5 - PMo - polyacrylamide showed that Tb3+, Nd3+, Eu3+ and Gd3+ were readily adsorbed, but adsorption was difficult for Ce4+, Sm3+ and Dy3+. (author)

  18. Experimental Study onMalignant Transformation of Human Bronchial Epithelial CellsInduced by Glycidyl Methacrylate and Analysis on its Methylation

    Institute of Scientific and Technical Information of China (English)

    WANG An Na; WANG Quan Kai; YANG Min; HU Jie; DONG Lin; andXU Jian Ning

    2014-01-01

    ObjectiveTo establish the model of human bronchial epithelial cells(16HBE) malignant transformation induced by glycidyl methacrylate(GMA)and define the different methylation genes at different stages. MethodsDNA was extracted at different 16HBE malignant phasesandchanges of genes DNA methylation atdifferent stages weredetectedusing Methylation chip of‘NimbleGen HG18 CpG Promoter Microarray Methylation’. Methylation-specific PCR (MSP) was usedto observe the methylation status ofsome genes, and then compared with the control groups. ResultsThe resultshowed that GMA induced 16HBE morphorlogical transformation at the dose of 8µg/mL, and cell exposed to GMA had 1374 genes in protophase, 825 genes inmetaphase, 1149 genes in anaphase, respectively; 30 genes are all methylation in the 3 stages; 318 genes in protophase but not inmetaphase and anaphase; 272 genes in metaphase but not inprotophase and anaphase; 683 genes in anaphase but not inmetaphase and protophase; 73 genes inprotophase andmetaphase but not in anaphase; 67 genes in protophase and anaphase but not inmetaphase; 59 genes inmetaphase and anaphase but not in protophase. ConclusionThe pattern of DNA methylation could change in the process of 16HBEinduced by GMA.

  19. Sorption of different phenol derivatives on functionalized macroporous nanocomposite of poly (glycidyl methacrylate-co-ethylene glycol dimethacrylate and acid modified bentonite

    Directory of Open Access Journals (Sweden)

    Marinović Sanja R.

    2014-01-01

    Full Text Available Macroporous nanocomposite of poly (glycidyl methacrylate-co-ethylene glycol dimethacrylate and acid modified bentonite was prepared by radical suspension copolymerization. Nanocomposite was functionalized with diethylene triamine (deta, by ring-opening reaction of the pendant epoxy groups. Functionalization was performed in order to enable phenol derivatives sorption. This new, not sufficiently investigated material, with developed porous structure was denoted CP-SA-deta. In this study, the influence of temperature on 4-nitrophenol (4NP sorption on CP-SA-deta was investigated. The chemisorption was estimated as dominant process since activation energy of sorption of 4NP of 54.8 kJ mol-1 was obtained. After determining the optimal sorption conditions for 4NP, the sorption of 2-nitrophenol (2NP and 2-chloro 4-nitrophenol (2Cl4NP on CP-SA-deta was investigated with respect to pH, initial concentration and contact time. The 2NP sorption was seldom tested, while according to our knowledge, the 2Cl4NP sorption was not investigated. The isotherm data were best fitted with Langmuir model, while the sorption dynamics obeyed the pseudo-second-order kinetic model for all derivatives. [Projekat Ministarstva nauke Republike Srbije, br. III 45001 i br. III 43009

  20. Formation of Glycidyl Fatty Acid Esters Both in Real Edible Oils during Laboratory-Scale Refining and in Chemical Model during High Temperature Exposure.

    Science.gov (United States)

    Cheng, Weiwei; Liu, Guoqin; Liu, Xinqi

    2016-07-27

    In the present study, the formation mechanisms of glycidyl fatty acid esters (GEs) were investigated both in real edible oils (soybean oil, camellia oil, and palm oil) during laboratory-scale preparation and refining and in chemical model (1,2-dipalmitin (DPG) and 1-monopalmitin (MPG)) during high temperature exposure (160-260 °C under nitrogen). The formation process of GEs in the chemical model was monitored using attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy. The results showed that the roasting and pressing process could produce certain amounts of GEs that were much lower than that produced in the deodorization process. GE contents in edible oils increased continuously and significantly with increasing deodorization time below 200 °C. However, when the temperature exceeded 200 °C, GE contents sharply increased in 1-2 h followed by a gradual decrease, which could verify a simultaneous formation and degradation of GEs at high temperature. In addition, it was also found that the presence of acylglycerol (DAGs and MAGs) could significantly increase the formation yield of GEs both in real edible oils and in chemical model. Compared with DAGs, moreover, MAGs displayed a higher formation capacity but substantially lower contribution to GE formation due to their low contents in edible oils. In situ ATR-FTIR spectroscopic evidence showed that cyclic acyloxonium ion intermediate was formed during GE formation derived from DPG and MPG in chemical model heated at 200 °C. PMID:27319409

  1. Preparation of high-capacity, weak anion-exchange membranes by surface-initiated atom transfer radical polymerization of poly(glycidyl methacrylate) and subsequent derivatization with diethylamine

    Science.gov (United States)

    Qian, Xiaolei; Fan, Hua; Wang, Chaozhan; Wei, Yinmao

    2013-04-01

    Ion-exchange membrane is of importance for the development of membrane chromatography. In this work, a high-capacity anion-exchange membrane was prepared by grafting of glycidyl methacrylate (GMA) onto the surface of regenerated cellulose (RC) membranes via surface-initiated atom transfer radical polymerization (SI-ATRP) and subsequent derivatization with diethylamine. Attenuated total reflectance Fourier-transform infrared (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) were used to characterize changes in the chemical functionality, surface topography and pore morphology of the modified membranes. The static capacity of the prepared anion-exchange membrane was evaluated with bovine serum albumin (BSA) as a model protein. The results indicated that the anion-exchange membrane which could reach a maximum capacity of 96 mg/mL for static adsorption possesses a higher adsorption capacity, and the adsorption capacity increases with the polymerization time. The effect of pH and salt concentration confirmed that the adsorption of BSA followed ion-exchange mechanism. The established method would have potential application in the preparation of anion-exchange membrane.

  2. Selective Controlled/Living Photoradical Polymerization of Glycidyl Methacrylate, Using a Nitroxide Mediator in the Presence of a Photosensitive Triarylsulfonium Salt

    Directory of Open Access Journals (Sweden)

    Eri Yoshida

    2012-09-01

    Full Text Available The controlled/living photoradical polymerization of glycidyl methacrylate (GMA was attained using 4-methoxy-2,2,6,6-tetramethylpiperidine-1-oxyl (MTEMPO as the mediator and (2RS,2'RS-azobis(4-methoxy-2,4-dimethylvaleronitrile as the initiator in the presence of (4-tert-butylphenyldiphenylsulfonium triflate (tBuS. Whereas the polymerization in the absence of MTEMPO yielded a gel-containing polymer, the MTEMPO-mediated polymerization produced poly(GMA bonded at the vinyl site, and retained the oxirane ring structure. No occurrence of the cationic ring-opening photopolymerization of the oxirane ring even in the presence of the photosensitive onium salt indicated that tBuS served as the photoelectron transfer agent between MTEMPO in their excited states at the propagating chain end. The resulting polymers had comparatively narrow molecular weight distributions of Mw/Mn = 1.46–1.48. The living nature of the MTEMPO-mediated polymerization was confirmed on the basis of a linear increase in the conversion-molecular weight plots and gel permeation chromatography (GPC analysis.

  3. Facile Synthesis of Magnetic Copolymer Microspheres Based on Poly(glycidyl methacrylate-co-N-isopropylacrylamide/Fe3O4 by Suspension Photopolymerization

    Directory of Open Access Journals (Sweden)

    Siti Zulaikha Mazlan

    2014-01-01

    Full Text Available Magnetic copolymer based on poly(glycidyl methacrylate-co-N-isopropylacrylamide microspheres was prepared by 2,2-dimethoxy-2-phenylacetophenone- (DMPP- photo initiated and poly(vinyl alcohol- (PVA- stabilized single step suspension photopolymerization. The effect of chemical interaction, morphology, and thermal properties by adding 0.1% w/v Fe3O4 in the copolymer was investigated. Infrared analysis (FTIR showed that (C=C band disappeared after copolymerization, indicating that the magnetic copolymer microspheres were successfully synthesized and two important bands at 908 cm−1 and 1550 cm−1 appear. These are associated with the epoxy group stretching of GMA and secondary amide (N–H/C–H deformation vibration of NIPAAm in magnetic microspheres. The X-ray diffraction (XRD result proved the incorporation of Fe3O4 nanoparticles with copolymer microspheres as peak of Fe3O4 was observed. Morphology study revealed that magnetic copolymer exhibited uniform spheres and smoother appearance when entrapped with Fe3O4 nanoparticles. The lowest percentage of Fe3O4 nanoparticles leached from the copolymer microspheres was obtained at pH 7. Finally, thermal property of the copolymer microspheres was improved by adding a small amount of Fe3O4 nanoparticles that has been shown from the thermogram.

  4. Inhibition of bladder cancer cell proliferation by allyl isothiocyanate (mustard essential oil)

    Energy Technology Data Exchange (ETDEWEB)

    Sávio, André Luiz Ventura, E-mail: savio.alv@gmail.com [UNESP – Universidade Estadual Paulista, Faculdade de Medicina de Botucatu, Departamento de Patologia, Botucatu, SP (Brazil); Nicioli da Silva, Glenda [UFOP – Universidade Federal de Ouro Preto, Escola de Farmácia, Departamento de Análises Clínicas, Ouro Preto, MG (Brazil); Salvadori, Daisy Maria Fávero [UNESP – Universidade Estadual Paulista, Faculdade de Medicina de Botucatu, Departamento de Patologia, Botucatu, SP (Brazil)

    2015-01-15

    Highlights: • AITC inhibits mutant and wild-type TP53 cell proliferation. • Morphological changes and cells debris were observed after AITC treatment in both cells. • BAX and BCL2 expression modulation was observed in wild-type TP53 cells. • BCL2, BAX and ANLN increased and S100P decreased expression was detected in mutated TP53 cells. • AITC effects in gene modulation are dependent TP53 gene status. - Abstract: Natural compounds hold great promise for combating antibiotic resistance, the failure to control some diseases, the emergence of new diseases and the toxicity of some contemporary medical products. Allyl isothiocyanate (AITC), which is abundant in cruciferous vegetables and mustard seeds and is commonly referred to as mustard essential oil, exhibits promising antineoplastic activity against bladder cancer, although its mechanism of action is not fully understood. Therefore, the aim of this study was to investigate the effects of AITC activity on bladder cancer cell lines carrying a wild type (wt; RT4) or mutated (T24) TP53 gene. Morphological changes, cell cycle kinetics and CDK1, SMAD4, BAX, BCL2, ANLN and S100P gene expression were evaluated. In both cell lines, treatment with AITC inhibited cell proliferation (at 62.5, 72.5, 82.5 and 92.5 μM AITC) and induced morphological changes, including scattered and elongated cells and cellular debris. Gene expression profiles revealed increased S100P and BAX and decreased BCL2 expression in RT4 cells following AITC treatment. T24 cells displayed increased BCL2, BAX and ANLN and decreased S100P expression. No changes in SMAD4 and CDK1 expression were observed in either cell line. In conclusion, AITC inhibits cell proliferation independent of TP53 status. However, the mechanism of action of AITC differed in the two cell lines; in RT4 cells, it mainly acted via the classical BAX/BCL2 pathway, while in T24 cells, AITC modulated the activities of ANLN (related to cytokinesis) and S100P. These data confirm

  5. Inhibition of bladder cancer cell proliferation by allyl isothiocyanate (mustard essential oil)

    International Nuclear Information System (INIS)

    Highlights: • AITC inhibits mutant and wild-type TP53 cell proliferation. • Morphological changes and cells debris were observed after AITC treatment in both cells. • BAX and BCL2 expression modulation was observed in wild-type TP53 cells. • BCL2, BAX and ANLN increased and S100P decreased expression was detected in mutated TP53 cells. • AITC effects in gene modulation are dependent TP53 gene status. - Abstract: Natural compounds hold great promise for combating antibiotic resistance, the failure to control some diseases, the emergence of new diseases and the toxicity of some contemporary medical products. Allyl isothiocyanate (AITC), which is abundant in cruciferous vegetables and mustard seeds and is commonly referred to as mustard essential oil, exhibits promising antineoplastic activity against bladder cancer, although its mechanism of action is not fully understood. Therefore, the aim of this study was to investigate the effects of AITC activity on bladder cancer cell lines carrying a wild type (wt; RT4) or mutated (T24) TP53 gene. Morphological changes, cell cycle kinetics and CDK1, SMAD4, BAX, BCL2, ANLN and S100P gene expression were evaluated. In both cell lines, treatment with AITC inhibited cell proliferation (at 62.5, 72.5, 82.5 and 92.5 μM AITC) and induced morphological changes, including scattered and elongated cells and cellular debris. Gene expression profiles revealed increased S100P and BAX and decreased BCL2 expression in RT4 cells following AITC treatment. T24 cells displayed increased BCL2, BAX and ANLN and decreased S100P expression. No changes in SMAD4 and CDK1 expression were observed in either cell line. In conclusion, AITC inhibits cell proliferation independent of TP53 status. However, the mechanism of action of AITC differed in the two cell lines; in RT4 cells, it mainly acted via the classical BAX/BCL2 pathway, while in T24 cells, AITC modulated the activities of ANLN (related to cytokinesis) and S100P. These data confirm

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

    Directory of Open Access Journals (Sweden)

    Xiaomin GAO

    2015-11-01

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

  7. Conversion of dimethyl ether on zeolite catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Abramova, A.V.; Kulumbegov, R.V.; Khadzhiev, S.N. [Russian Academy of Sciences, Moscow (Russian Federation). A.V. Topchiev Inst. of Petrochemical Synthesis

    2006-07-01

    Catalytic conversion of dimethyl ether to hydrocarbons was investigated using zeolite catalyst ZSM-5 type. 2% MexOy - 60% HZVM(analogue of ZSM-5)/Al{sub 2}O{sub 3}, (Me = Zn, Ga, Fe, Co, V, Ni) catalyst samples have been obtained. The reaction was carried out in a fixed bed reaction set-up at 350-400 C, pressure 3 MPa, gas mix (% vol.): 24 DME, 76 N{sub 2}, WHSV=1300 l/l-{sub kat.}h. Most effective catalysts of DME conversion are pentasil based catalysts with promoter metals zinc, iron and cobalt by totality DME-conversion, gas and liquid hydrocarbon selectivity, ethylene and propylene content in gas. The best work temperatures are 350 and 375 C, thereupon increasing of temperature to 400 C leads to considerable growth of methane in hydrocarbon gas. Liquid hydrocarbons have high content of aromatics and iso-paraffins. Liquid hydrocarbon product is characterized by high octane number (RON) 90-98. (orig.)

  8. Radiation induced crosslinking of cellulose ethers

    International Nuclear Information System (INIS)

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

  9. Explosion and detonation characteristics of dimethyl ether.

    Science.gov (United States)

    Mogi, Toshio; Horiguchi, Sadashige

    2009-05-15

    In this study, the explosion and detonation characteristics of dimethyl ether (DME) were experimentally investigated. A spherical pressure vessel with an internal volume of 180L was used as the explosion vessel. Therefore, tubes 10m in length with internal diameters of 25mm and 50mm were used as detonation tubes. In addition, we compared the characteristics of DME with those of propane since DME is considered as a substitute fuel for liquid petroleum gas (LPG). At room temperature and atmospheric pressure, the maximum explosive pressure increased tenfold. The explosion index (K(G) values), an indicator of the intensity of an explosion, was larger than that of propane, indicating that the explosion was intense. No experimental study has been conducted on the detonation behavior of DME so far, but this research confirmed a transition to detonation. The detonation characteristics were similar to the characteristics of the Chapman-Jouguet detonation, and the concentration range for detonation was from 5.5% to 9.0%. PMID:18774641

  10. Nickel-catalyzed enantioselective hydrovinylation of silyl-protected allylic alcohols:An efficient access to homoallylic alcohols with a chiral quaternary center

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Asymmetric hydrovinylation of silyl-protected allylic alcohols catalyzed by nickel complexes of chiral spiro phosphoramidite ligands was developed.A series of homoallylic alcohols with a chiral quaternary center were produced in high yields(up to 97%) and high enantioselectivities(up to 95% ee).The reaction provides an efficient method for preparing bifunctional compounds with a chiral quaternary carbon center.

  11. Titanocene Dichloride Complexes Bonded to Carbosilane Dendrimers Via a Spacer of Variable Length – Molecular Dynamics Calculations and Catalysis of Allylic Coupling Reactions

    Czech Academy of Sciences Publication Activity Database

    Strašák, Tomáš; Jaroschik, F.; Malý, M.; Čermák, Jan; Sýkora, Jan; Fajgar, Radek; Karban, Jindřich; Harakat, D.

    2014-01-01

    Roč. 409, SI (2014), s. 137-146. ISSN 0020-1693 R&D Projects: GA MŠk(CZ) LC06070 Grant ostatní: UJEP(CZ) GA13-06989S Institutional support: RVO:67985858 Keywords : metallodendrimers * titanocene dichloride * allylic homocoupling * molecular dynamics Subject RIV: CC - Organic Chemistry Impact factor: 2.046, year: 2014

  12. Chiral N-1-adamantyl-N-trans-cinnamylaniline type ligands: synthesis and application to palladium-catalyzed asymmetric allylic alkylation of indoles.

    Science.gov (United States)

    Mino, Takashi; Nishikawa, Kenji; Asano, Moeko; Shima, Yamato; Ebisawa, Toshibumi; Yoshida, Yasushi; Sakamoto, Masami

    2016-08-21

    Such chiral phosphine-internal olefin hybrid type ligands as N-1-adamantyl-N-cinnamylaniline derivatives 1 with C(aryl)-N(amine) bond axial chirality were synthesized and utilized for the palladium-catalyzed asymmetric allylic alkylation of indoles to afford the desired products in high enantioselectivities (up to 98% ee). PMID:27425209

  13. Exciton Coupling in Circular Dichroic Spectroscopy as a Tool for Establishing the Absolute Configuration of alpha,beta-Unsaturated Esters of Allylic Alcohols

    DEFF Research Database (Denmark)

    Lauridsen, A.; Cornett, Claus; Christensen, S. B.

    1991-01-01

    alpha-beta-Unsaturated esters of allylic alcohols have been shown to exhibit exciton coupling by circular dichroic spectroscopy. This coupling permits the establishment of the absolute configuration. The method was used to prove the absolute configuration at C-2 of archangelolide. Detailed NMR sp...... spectral studies of the prepared model structures may be used as a reference for stereoisomeric guaianolides....

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-10-01

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

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

    Directory of Open Access Journals (Sweden)

    Volker Altstaedt

    2003-12-01

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

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

    Science.gov (United States)

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

    2016-02-01

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

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

    Directory of Open Access Journals (Sweden)

    Rebecca S. L. Yee

    2013-08-01

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

  18. Crystal structure of N-(1-allyl-3-chloro-4-ethoxy-1H-indazol-5-yl-4-methoxybenzenesulfonamide

    Directory of Open Access Journals (Sweden)

    Hakima Chicha

    2014-09-01

    Full Text Available In the title compound, C19H20ClN3O4S, the benzene ring is inclined to the indazole ring system (r.m.s. deviation = 0.014 Å by 65.07 (8°. The allyl and ethoxy groups are almost normal to the indazole ring, as indicated by the respective torsion angles [N—N—C—C = 111.6 (2 and C—C—O—C = −88.1 (2°]. In the crystal, molecules are connected by N—H...N hydrogen bonds, forming helical chains propagating along [010]. The chains are linked by C—H...O hydrogen bonds, forming a three-dimensional network.

  19. Crystal structure of (Z-3-allyl-5-(4-chlorobenzylidene-2-sulfanylidene-1,3-thiazolidin-4-one

    Directory of Open Access Journals (Sweden)

    Rahhal El Ajlaoui

    2015-12-01

    Full Text Available In the title compound, C13H10ClNOS2, the dihedral angle between the rhodanine (r.m.s. deviation = 0.008 Å and 4-chlorobenzylidene rings is 1.79 (11°. The allyl group attached to the N atom, which lies almost perpendicular to the rhodanine ring, is disordered over two orientations in a 0.519 (13:0.481 (13 ratio. A short intramolecular C—H...S interaction closes an S(6 ring. In the crystal, molecules are linked by π–π stacking interactions [centroid–centroid separation = 3.600 (15 Å], generating inversion dimers.

  20. The adsorption stability & inhibition by allyl-thiourea of bulk nanocrystalline ingot iron in dilute HCl solution

    Science.gov (United States)

    Shen, C. B.; Wang, S. G.; Yang, H. Y.; Long, K.; Wang, F. H.

    2006-12-01

    The inhibitive effect of thiourea's (TU) alkyl derivative—allyl-thiourea (ATU) on the corrosion behaviors of bulk nanocrystalline and conventional polycrystalline ingot iron (BNII & CPII) was tested. Results indicate that BNII is less prone to get corrosive than its coarse grain counterpart in blank 1 mol L -1 HCl at room temperature. When CPII and BNII were immersed for a very short time in the corrosive solution inhibited by ATU, namely, 5 min, no inductive loop appears at different concentrations. When time became prolonged, for BNII, a Warburg impedance appeared. Inhibited by ATU, the electrodes composed of the samples are polarized anodically during the potentiodynamic polarization tests, the phenomena of desorption happens at the concentration of 100 mg L -1, but the variation between potential Edes is obvious. The inhibition effect of ATU for BNII is very limited by comparison with CPII in dilute HCl.

  1. Crystal structure of (E-4-(acetoxyimino-N-allyl-3-isopropyl-2,6-diphenylpiperidine-1-carbothioamide

    Directory of Open Access Journals (Sweden)

    T. Mohandas

    2015-08-01

    Full Text Available The title compound, C26H31N3O2S, crystallizes with two molecules (A and B in the asymmetric unit. In each case, the piperidine ring exists in a twist-boat conformation. The dihedral angle between the phenyl rings is 46.16 (12° in molecule A and 44.95 (12° in molecule B. In both molecules, the allyl side chain is disordered over two orientations in a 0.649 (9:0.351 (9 ratio for molecule A and 0.826 (10:0.174 (10 ratio for molecule B. In the crystal, neither molecule forms a hydrogen bond from its N—H group, presumably due to steric hindrance. A+A and B+B inversion dimers are formed, linked by pairs of weak C—H...O hydrogen bonds enclosing R22(22 ring motifs.

  2. Crystal structure of (E)-4-(acetoxyimino)-N-allyl-3-isopropyl-2,6-diphenylpiperidine-1-carbothioamide

    OpenAIRE

    Mohandas, T; K. Gokula Krishnan; Balamurugan, S.; Harrison, William T. A.; Thanikachalam, V.; Sakthivel, P.

    2015-01-01

    The title compound, C26H31N3O2S, crystallizes with two molecules (A and B) in the asymmetric unit. In each case, the piperidine ring exists in a twist-boat conformation. The dihedral angle between the phenyl rings is 46.16 (12)° in molecule A and 44.95 (12)° in molecule B. In both molecules, the allyl side chain is disordered over two orientations in a 0.649 (9):0.351 (9) ratio for molecule A and 0.826 (10):0.174 (10) ratio for molecule B. In the crystal, neither molecule forms a hydrogen bon...

  3. Glycidyl methacrylate-co-N-vinyl-2-pyrrolidone coated polypropylene strips: Synthesis, characterization and standardization for dot-enzyme linked immunosorbent assay

    Energy Technology Data Exchange (ETDEWEB)

    Tyagi, Charu; Tomar, Lomas [Centre for Biomedical Engineering, Indian Institute of Technology, Delhi 110016 (India); Singh, Harpal [Centre for Biomedical Engineering, Indian Institute of Technology, Delhi 110016 (India)], E-mail: tyagicharu11@rediffmail.com

    2009-01-26

    Glycidyl methacrylate and N-vinyl-2-pyrrolidone (GMA-co-NVP) copolymers with various GMA:NVP ratios were synthesized by solution polymerization technique in toluene using 2,2'-azobisisobutyronitrile (AIBN) as free radical initiator and dip coated onto polypropylene strips. The copolymer composition in polymeric coatings was confirmed by proton NMR spectroscopy. Various techniques like FTIR, SEM and contact angle were used for surface characterization of the polymer coatings. These polymer coated strips were evaluated and standardized for their application in dot-ELISA in two steps. In first step, specificity, sensitivity and reproducibility of the assay on developed polymer coated strips was evaluated through a model system using rabbit anti-goat IgG, goat anti-rabbit IgG and goat anti-rabbit IgG HRP (horseradish peroxidase)-conjugate. Polymer coating with GMA-NVP mol% ratio of 78:22 was able to detect rabbit anti-goat IgG antibody at a concentration as low as 2 ng mL{sup -1} with 1% BSA as blocking agent using antispecies IgG peroxidase conjugate diluted 1500 times. In the second step, the sensitivity and specificity of the developed system was established with human blood and finally used to identify the source of mosquito blood meal which is an important parameter in epidemiological studies, particularly in determining the role of mosquito in malaria transmission. The time duration of standardized assay with developed polymer coated strips was cut down to one hour compared to the 3-4 h required in usual dot-ELISA.

  4. SYNTHESIS, STRUCTURE AND BIOLOGICAL ACTIVITY OF N(4-ALLYL-3-THIOSEMICARBAZONES AND THEIR COORDINATION COMPOUNDS WITH SOME 3D METALS

    Directory of Open Access Journals (Sweden)

    Vasilii GRAUR

    2016-02-01

    Full Text Available The paper presents a review of different N(4-allyl-3-thiosemicarbazones and their coordination compounds described in literature. N(4-allyl-3-thiosemicarbazide can form corresponding thiosemicarbazones with aliphatic, aromatic and heteroaromatic carbonyl compounds. In the presence of transitional metal ions they can form coordination compounds of different structures. Both coordination compounds and proligands manifest antitumor, antibacterial, antiviral, and antimalarial activities. Copper(II coordination compounds with these ligands manifest better antitumor activity than corresponding proligands. SINTEZA, STRUCTURA ŞI ACTIVITATEA BIOLOGICĂ A N(4-ALIL-3-TIOSEMICARBAZONELOR ŞI A COMPUŞILOR COORDINATIVI AI UNOR METALE 3D CU ACEŞTI LIGANZILucrarea prezintă o revistă a N(4-alil-3-tiosemicarbazonelor şi a compuşilor coordinativi cu aceşti liganzi descrise în literatura de specialitate. N(4-alil-3-tiosemicarbazida formează tiosemicarbazone cu aldehide şi cetone alifatice, aro­matice şi heteroaromatice. În prezenţa ionilor de metale de tranziţie acestea pot forma compuşi coordinativi cu diferite structuri. N(4-alil-3-tiosemicarbazonele şi compuşii coordinativi manifestă activitate antitumorală, antibacterială, antivirală şi antimalarică. Compuşii coordinativi ai cuprului cu aceşti liganzi manifestă activitate antitumorală sporită în comparaţie cu N(4-alil-3-tiosemicarbazonele corespunzătoare. 

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

    Science.gov (United States)

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

    1998-01-01

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

  6. Influence of Cellulose Ethers on Hydration Products of Portland Cement

    Institute of Scientific and Technical Information of China (English)

    MA Baoguo; OU Zhihua; JIAN Shouwei; XU Rulin

    2011-01-01

    Cellulose ethers are widely used to mortar formulations, and it is significant to understand the interaction between cellulose ethers and cement pastes. FT-IR spectra, thermal analysis and SEM are used to investigate hydration products in the cement pastes modified by HEMC and HPMC in this article. The results show that the hydration products in modified cement pastes were finally identical with those in the unmodified cement paste, but the major hydration products, such as CH (calcium hydroxide), ettringite and C-S-H, appeared later in the modified cement pastes than in the unmodified cement paste. The cellulose ethers decrease the outer products and increase inner products of C-S-H gels. Compared to unmodified cement pastes, no new products are found in the modified cement pastes in the present experiment. The HEMC and HPMC investigation shows almost the same influence on the hydration products of Portland cement.

  7. Novel Unsaturated Sucrose Ethers and Their Application as Monomers

    Directory of Open Access Journals (Sweden)

    Maria T. Barros

    2007-03-01

    Full Text Available Novel unsaturated ethers were synthesised in good yields starting from sucrose,using a two-step mild and efficient procedure based on the Gassman method, whichconsists in forming a vinyl group by the elimination of ethanol from mixed acetals withtrimethylsilyl trifluoromethanesulfonate in the presence of alkyl amines. Mixed acetals arereadily obtained from the corresponding alcohols and ethyl vinyl ether, using an acidiccatalyst. Conventional etherification involving a primary halide was also examined. Themonomers thus obtained were successfully polymerised by a free radical mechanism,yielding unbranched linear and soluble polymers with pending sucrose moieties, and someof their physical properties were determined.

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

    OpenAIRE

    Gaca, Jerzy; Gackowska, Alicja; Belt, Natalia

    2008-01-01

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

  9. Concise synthesis of ether analogues of lysobisphosphatidic acid.

    Science.gov (United States)

    Jiang, Guowei; Xu, Yong; Falguières, Thomas; Gruenberg, Jean; Prestwich, Glenn D

    2005-09-01

    We describe a versatile, efficient method for the preparation of ether analogues of (S,S)-lysobisphosphatidic acid (LBPA) and its enantiomer from (S)-solketal. Phosphorylation of a protected sn-2-O-octadecenyl glyceryl ether with 2-cyanoethyl bis-N,N-diisopropylamino phosphine and subsequent deprotection generated the bisether LBPA analogues. By simply changing the sequence of deprotection steps, we obtained the (R,R)- and (S,S)-enantiomers of 2,2'-bisether LBPA. An ELISA assay with anti-LBPA monoclonal antibodies showed that the bisether LBPAs were recognized with the same affinity as the natural 2,2'-bisoleolyl LBPA. [reaction: see text] PMID:16119911

  10. Mutual solubility in the system uranyl trichloroacetate--water--diethyl ether

    Energy Technology Data Exchange (ETDEWEB)

    Vdovenko, V.M.; Baluev, A.V.; Suglobova, I.G.

    1975-01-01

    A study was made of mutual solubility in the system uranyl trichloroacetate--water--diethyl ether at 25/sup 0/C. It was found that the solubility of the salt in ether and the composition of the lower phase depend on the water content of the ternary system. On the basis of ir spectra of ether solutions of uranyl trichloroacetate in the presence of semiheavy water (HDO) the structure of the hydration envelope of the complex in diethyl ether was established.

  11. Effect of Backbone Structure on Membrane Properties for Poly(arylene ether) Random and Multiblock Copolymers

    OpenAIRE

    Rowlett, Jarrett Robert

    2014-01-01

    Poly(arylene ether)s are a well-established class of thermoplastics that are known for their mechanical toughness, thermal stability, and fabrication into membranes. These materials can undergo a myriad of modifications including backbone structure variability, sulfonation, and crosslinking. In this dissertation, structure-property relationships are considered for poly(arylene ether)s with regard to membrane applications for proton exchange and gas separation membranes. All of the proton...

  12. 40 CFR 721.1580 - Disubstituted benzene ether, polymer with substituted phenol (generic).

    Science.gov (United States)

    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...

  13. Carboxymethyl ethers of cellulose obtained from secondary products of fine-stapled cotton

    International Nuclear Information System (INIS)

    This article is devoted to synthesis and properties of carboxymethyl ethers of cellulose obtained from secondary products of fine-stapled cotton. The investigation of extraction conditions of cellulose on the quality of carboxymethyl ethers of cellulose is conducted. The qualitative characteristics of cotton cellulose are considered. The synthesis of carboxymethyl ethers of cellulose from obtained cellulose is described.

  14. Determination of bisphenol diglycidyl ether residues in canned foodstuffs by high performance liquid chromatographytandem mass spectrometry%高效液相色谱-串联质谱法同时测定肉类罐头中双酚-二缩水甘油醚

    Institute of Scientific and Technical Information of China (English)

    赵晓亚; 付晓芳; 王鹏; 李晶; 胡小钟

    2012-01-01

    An accurate quantitative determination and confirmative method for bisphenol diglycidyl ether residues, bisphenol A diglycidyl ether ( BADGE) , bisphenol F diglycidyl ether (BFDGE), bisphenol A (2,3-dihydroxypropyl)glycidyl ether (BADGE -H2O) , bisphenol A bis (2,3-dihydroxypropyl) ether (BADGE -2H2O) , bisphenol A (3-chloro-2-hydroxy propyl) (2,3-dihydroxypropyl) ether (BADGE -H2O -HC1) , bisphenol A (3-chloro-2-hydroxypropyl)glycidyl ether (BADGE -HC1) , bisphenol A bis(3-chloro-2-hydroxypropyl) ether (BADGE -2HC1) , bisphenol F bis ( 2, 3-dihydroxypropyl) ether (BFDGE -2H2O), bisphenol F bis ( 3-chloro-2-hydroxypropyl) ether ( BFDGE -2HC1) in canned foodstuffs by high performance liquid chroma-tography-tandem mass spectrometry ( HPLC-MS/MS) has been established. The sample was extracted with teri-butylmethyl ether and the extract was cleaned-up and concentrated on a Waters Oasis HLB column. The target compounds were analyzed by HPLC-MS/MS on a C18column by the gradient elution with methanol and 5 mmol/L ammonium acetate containing 0. 1 % formic acid in a multiple reaction monitoring (MRM) scan mode. External matrix standard solutions were used for the quantitative determination and the calibration curves showed good linearity in the concentration range of 10. 0 -2 000. 0 μg/L for the nine target compounds. The limits of quantification of the nine compounds were 10.0 jxg/kg (S/N≥10). The average recoveries of the nine compounds ranged from 79. 6% to 100. 9% at the spiked levels of 10. 0, 100. 0, 1 000. 0 μg/kg with the relative standard deviations (RSDs) of 6. 3% - 12. 1%. The method is sensitive, accurate, and suitable for the rapid determination of bisphenol diglycidyl ether residues in canned foodstuffs.%建立了同时测定肉类罐头中双酚A-二缩水甘油醚(BADGE)、双酚F-二缩水甘油醚(BFDGE)及其衍生物双酚A-(2,3-二羟丙基)甘油醚(BADGE·H2O)、双酚A-双(2,3-二羟丙基)醚(BADGE·2H2O)、双酚A-(3-氯-2-羟丙基)(2,3-

  15. Synthesis of Hydroxytyrosyl Alkyl Ethers from Olive Oil Waste Waters

    Directory of Open Access Journals (Sweden)

    Juan Fernández-Bolaños

    2009-05-01

    Full Text Available The preparation of a new type of derivatives of the naturally occurring antioxidant hydroxytyrosol is reported. Hydroxytyrosyl alkyl ethers were obtained in high yield by a three-step procedure starting from hydroxytyrosol isolated from olive oil waste waters. Preliminary results obtained by the Rancimat method have shown that these derivatives retain the high protective capacity of free hydroxytyrosol.

  16. Aqueous alkali metal hydroxide insoluble cellulose ether membrane

    Science.gov (United States)

    Hoyt, H. E.; Pfluger, H. L. (Inventor)

    1969-01-01

    A membrane that is insoluble in an aqueous alkali metal hydroxide medium is described. The membrane is a resin which is a water-soluble C2-C4 hydroxyalkyl cellulose ether polymer and an insolubilizing agent for controlled water sorption, a dialytic and electrodialytic membrane. It is particularly useful as a separator between electrodes or plates in an alkaline storage battery.

  17. Selected Methods of Dehalogenation of Polybrominated Diphenyl Ethers

    Czech Academy of Sciences Publication Activity Database

    Vajglová, Zuzana; Vychodilová, Hana; Křišťál, Jiří; Kaštánek, František; Jiřičný, Vladimír

    Frankfurt: DECHEMA, 2011, P05.04. ISBN N. [European Congress of Chemical Engineering /8./. Berlin (DE), 25.09.2011-29.09.2011] Institutional research plan: CEZ:AV0Z40720504 Keywords : polybrominated diphenyl ethers * concentrations * waste waters Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  18. Synthesis of Hydroxytyrosyl Alkyl Ethers from Olive Oil Waste Waters

    OpenAIRE

    2009-01-01

    The preparation of a new type of derivatives of the naturally occurring antioxidant hydroxytyrosol is reported. Hydroxytyrosyl alkyl ethers were obtained in high yield by a three-step procedure starting from hydroxytyrosol isolated from olive oil waste waters. Preliminary results obtained by the Rancimat method have shown that these derivatives retain the high protective capacity of free hydroxytyrosol.

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

    DEFF Research Database (Denmark)

    Norrman, K.; Krebs, Frederik C

    2004-01-01

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

  20. Li-air batteries having ether-based electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Amine, Khalil; Curtiss, Larry A; Lu, Jun; Lau, Kah Chun; Zhang, Zhengcheng; Sun, Yang-Kook

    2015-03-03

    A lithium-air battery includes a cathode including a porous active carbon material, a separator, an anode including lithium, and an electrolyte including a lithium salt and polyalkylene glycol ether, where the porous active carbon material is free of a metal-based catalyst.

  1. Enzymatic network for production of ether amines from alcohols

    DEFF Research Database (Denmark)

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

    2016-01-01

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

  2. The ether lipid-deficient mouse: tracking down plasmalogen functions.

    Science.gov (United States)

    Gorgas, Karin; Teigler, Andre; Komljenovic, Dorde; Just, Wilhelm W

    2006-12-01

    Chemical and physico-chemical properties as well as physiological functions of major mammalian ether-linked glycerolipids, including plasmalogens were reviewed. Their chemical structures were described and their effect on membrane fluidity and membrane fusion discussed. The recent generation of mouse models with ether lipid deficiency offered the possibility to study ether lipid and particularly plasmalogen functions in vivo. Ether lipid-deficient mice revealed severe phenotypic alterations, including arrest of spermatogenesis, development of cataract and defects in central nervous system myelination. In several cell culture systems lack of plasmalogens impaired intracellular cholesterol distribution affecting plasma membrane functions and structural changes of ER and Golgi cisternae. Based on these phenotypic anomalies that were accurately described conclusions were drawn on putative functions of plasmalogens. These functions were related to cell-cell or cell-extracellular matrix interactions, formation of lipid raft microdomains and intracellular cholesterol homeostasis. There are several human disorders, such as Zellweger syndrome, rhizomelic chondrodysplasia punctata, Alzheimer's disease, Down syndrome, and Niemann-Pick type C disease that are distinguished by altered tissue plasmalogen concentrations. The role plasmalogens might play in the pathology of these disorders is discussed. PMID:17027098

  3. Synthesis of new indolyl crown ethers catalyzed with ferric hydrogensulfate

    Institute of Scientific and Technical Information of China (English)

    Hossein Eshghi; Mohammad Rahimizadeh; Zahra Bakhtiarpoor; Mehdi Pordel

    2012-01-01

    Efficient reaction of bis-indolyl podand with different aldehydes using Fe(HSO4)3 as catalyst to afford the corresponding new indolyl crown ethers is described.The structures of three distinct isomers have been optimized using HyperChem geometry optimizations.Also percentage of each isomer was obtained with 1H NMR spectroscopy.

  4. A Review on Mutagenicity Testing for Hazard Classification of Chemicals at Work: Focusing on in vivo Micronucleus Test for Allyl Chloride.

    Science.gov (United States)

    Rim, Kyung-Taek; Kim, Soo-Jin

    2015-09-01

    Chemical mutagenicity is a major hazard that is important to workers' health. Despite the use of large amounts of allyl chloride, the available mutagenicity data for this chemical remains controversial. To clarify the mutagenicity of allyl chloride and because a micronucleus (MN) test had not yet been conducted, we screened for MN induction by using male ICR mice bone marrow cells. The test results indicated that this chemical is not mutagenic under the test conditions. In this paper, the regulatory test battery and several assay combinations used to determine the genotoxic potential of chemicals in the workplace have been described. Further application of these assays may prove useful in future development strategies of hazard evaluations of industrial chemicals. This study also should help to improve the testing of this chemical by commonly used mutagenicity testing methods and investigations on the underlying mechanisms and could be applicable for workers' health. PMID:26929826

  5. Structure and stability of acrolein and allyl alcohol networks on Ag(111) from density functional theory based calculations with dispersion corrections

    Science.gov (United States)

    Ferullo, Ricardo M.; Branda, Maria Marta; Illas, Francesc

    2013-11-01

    The interaction of acrolein and allyl alcohol with the Ag(111) surface has been studied by means of periodic density functional theory based calculations including explicitly dispersion terms. Different coverage values have been explored going from isolated adsorbed molecules to isolated dimers, interacting dimers or ordered overlayers. The inclusion of the dispersion terms largely affects the calculated values of the adsorption energy and also the distance between adsorbed molecule and the metallic surface but much less the adsorbate-adsorbate interactions. Owing to the large dipole moment of acrolein, the present calculations predict that at high coverage this molecule forms a stable extensive two-dimensional network on the surface, caused by the alignment of the adsorbate dipoles. For the case of allyl alcohol, dimers and complex networks exhibit similar stability.

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

    OpenAIRE

    Vijayakumar Thulasi; Thundil Karrupa Raj Rajagopal; Nanthagopal Kasianantham

    2011-01-01

    The spray characteristics of the diesel fuel are greatly affected by the cavitation formed inside the injector due to the high pressure differential across the nozzle. Many researchers across the globe are exploring the potential of using diethyl ether and dimethyl ether as an alternate for diesel fuel to meet the strict emission norms. Due to the variation in the fuel properties the internal flow characteristics in injectors for ether fuels are expected to be different from that of the...

  7. γ‐ and δ-Lactams through Palladium-Catalyzed Intramolecular Allylic Alkylation: Enantioselective Synthesis, NMR Investigation, and DFT Rationalization

    DEFF Research Database (Denmark)

    Bantreil, Xavier; Prestat, Guillaume; Moreno, Aitor;

    2011-01-01

    The Pd-catalyzed intramolecular allylic alkylation of unsaturated amides to give gamma- and delta-lactams has been studied in the presence of chiral ligands. Ligand (R)-3,5-tBu-MeOBIPHEP (MeOBIPHEP=6,6'-dimethoxybiphenyl-2,2-diyl)bis(diphenylphosphine)) afforded the best results and allowed the c...... reaction pathways. The calculated energy differences were in good agreement with the experimentally observed enantiomeric ratios....

  8. Palladium-Catalyzed C-H Arylation of α,β-Unsaturated Imines: Catalyst-Controlled Synthesis of Enamine and Allylic Amine Derivatives.

    Science.gov (United States)

    Li, Minyan; González-Esguevillas, María; Berritt, Simon; Yang, Xiaodong; Bellomo, Ana; Walsh, Patrick J

    2016-02-18

    A unique chemo- and regioselective α- and γ-arylation of palladium azapentadienyl intermediates is presented. Two distinct catalysts and sets of conditions successfully controlled the regioselectivity of the arylation. These methods provide the first umpolung C-H functionalization of azapentadienyl palladium intermediates and enable the divergent synthesis of allylic amine and enamine derivatives, which are of significant interest in the pharmaceutical industry. PMID:26846375

  9. Identifying Barbiturate Binding Sites in a Nicotinic Acetylcholine Receptor with [3H]Allyl m-Trifluoromethyldiazirine Mephobarbital, a Photoreactive Barbiturate

    OpenAIRE

    Hamouda, Ayman K.; Stewart, Deirdre S.; Chiara, David C.; Savechenkov, Pavel Y.; Bruzik, Karol S.; Cohen, Jonathan B.

    2014-01-01

    At concentrations that produce anesthesia, many barbituric acid derivatives act as positive allosteric modulators of inhibitory GABAA receptors (GABAARs) and inhibitors of excitatory nicotinic acetylcholine receptors (nAChRs). Recent research on [3H]R-mTFD-MPAB ([3H]R-5-allyl-1-methyl-5-(m-trifluoromethyldiazirinylphenyl)barbituric acid), a photoreactive barbiturate that is a potent and stereoselective anesthetic and GABAAR potentiator, has identified a second class of intersubunit binding si...

  10. Anti-inflammatory potential of allyl-isothiocyanate – role of Nrf2, NF-κB and microRNA-155

    OpenAIRE

    Wagner, Anika Eva; Boesch-Saadatmandi, Christine; Dose, Janina; Schultheiss, Gerhard; Rimbach, Gerald

    2012-01-01

    Abstract In this study, the underlying mechanisms of the potential anti-inflammatory properties of allyl-isothiocyanate (AITC) were analysed in vitro and in vivo. Murine RAW264.7 macrophages stimulated with lipopolysaccharide (LPS) were supplemented with increasing concentrations of AITC. In addition, C57BL/6 mice (n= 10 per group) were fed a pro-inflammatory high-fat diet and AITC was administered orally via gavage for 7 days. Biomarkers of inflammation were determined both in cultured cells...

  11. Intramolecular carbolithiation of N-allyl-ynamides: an efficient entry to 1,4-dihydropyridines and pyridines – application to a formal synthesis of sarizotan

    Directory of Open Access Journals (Sweden)

    Wafa Gati

    2012-12-01

    Full Text Available We have developed a general synthesis of polysubstituted 1,4-dihydropyridines and pyridines based on a highly regioselective lithiation/6-endo-dig intramolecular carbolithiation from readily available N-allyl-ynamides. This reaction, which has been successfully applied to the formal synthesis of the anti-dyskinesia agent sarizotan, further extends the use of ynamides in organic synthesis and further demonstrates the synthetic efficiency of carbometallation reactions.

  12. (Z)-Selective Enol Triflation of α-Alkoxyacetoaldehydes: Application to Synthesis of (Z)-Allylic Alcohols via Cross-Coupling Reaction and [1,2]-Wittig Rearrangement.

    Science.gov (United States)

    Kurosawa, Fumiya; Nakano, Takeo; Soeta, Takahiro; Endo, Kohei; Ukaji, Yutaka

    2015-06-01

    The stereoselective transformation of α-alkoxyacetoaldehydes to the corresponding (Z)-vinyl triflates was achieved by treatment with phenyl triflimide and DBU. The stereochemistry was explained by the "syn-effect," which was attributed primarily to an σ → π* interaction. The β-alkoxy vinyl triflates obtained were applied to the stereoselective synthesis of structurally diverse (Z)-allylic alcohols via transition metal-catalyzed cross-coupling reaction and [1,2]-Wittig rearrangement. PMID:25970239

  13. Palladium-Catalyzed Carbonylation of (Hetero)Aryl, Alkenyl and Allyl Halides by Means of N-Hydroxysuccinimidyl Formate as CO Surrogate.

    Science.gov (United States)

    Barré, Anaïs; Ţînţaş, Mihaela-Liliana; Alix, Florent; Gembus, Vincent; Papamicaël, Cyril; Levacher, Vincent

    2015-07-01

    An efficient Pd-catalyzed carbonylation protocol is described for the coupling of a large panel of aryl, heteroaryl, benzyl, vinyl and allyl halides 2 with the unusual N-hydroxysuccinimidyl (NHS) formate 1 as a CO surrogate to afford the corresponding valuable NHS esters 3. High conversion to the coupling products was achieved with up to 98% yield by means of Pd(OAc)2/Xantphos catalyst system. PMID:26098725

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

    Directory of Open Access Journals (Sweden)

    Mosstafa Kazemi

    2013-10-01

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

  15. Poli (metil azoteto de glicidila - GAP. I: síntese e caracterização Glycidyl azide polymer (GAP. I: syntheses and characterization

    Directory of Open Access Journals (Sweden)

    Sandro P. Ribeiro

    2012-01-01

    Full Text Available O poli (metil azoteto de glicidila - GAP - é um material energético que pode ser utilizado como aglutinante (binder e como plastificante energético em compostos explosivos e propulsores de foguetes. Neste trabalho, foi abordada a síntese do (GAP através da conversão direta da epicloridrina (ECH a GAP. Os reagentes utilizados foram azida de sódio, epicloridrina e vários álcoois extensores de cadeias, o etanodiol, o 1,4-butanodiol, o dietilenoglicol e o glicerol. Alguns parâmetros de operação foram avaliados, como o tempo de reação, a proporção entre os reagentes, dois tipos de solvente e a ordem de adição dos reagentes. A variável observada para a análise foi a massa molecular do GAP. Todos os materiais sintetizados também foram caracterizados por análises de FTIR, UV, RMN, DSC, análise elementar e TGA. Uma maior massa molecular, maior rendimento e uma melhor conversão do grupo azida a GAP foram obtidos com a adição de epicloridrina sobre a azida de sódio e usando DMF como solvente.GAP is an aliphatic polyether that includes hydroxyl groups and highly energetic azide groups. Thus, it is an energetic material that can be used as binder or plasticizing agent in propellants and explosive mixtures. The glycidyl azide polymer (GAP was synthesized and characterized by direct conversion of epichlorohydrin. GAP was synthesized by reaction of sodium azide, epichlorohydrin, and some extensor alcohols. The investigation focused on the effects of some key reaction parameters including reagent proportions, reaction time and two different solvents. The product was characterized by FTIR, UV, NMR, DSC, elemental analysis, TGA and GPC. The species were also evaluated through molecular weight (GPC, glass transition temperature (DSC, ignition time and sensitivity.

  16. Comparative photophysical behaviour of naphthalene-linked crown ethers and aza crown ethers of varying cavity dimensions

    Indian Academy of Sciences (India)

    Subhodip Samanta; Pinki Saha Sardar; Shyam Sundar Maity; Anirban Pal; Maitrayee Basu Roy; Sanjib Ghosh

    2007-03-01

    A comparative time-resolved emission studies of several naphtho-crown ethers I-V, where metal ions can be complexed in a predetermined orientation with respect to the naphthalene (Naph) - plane and naphthalene-linked aza crown ethers (L1 and L2) have been presented. In both the systems, crown ethers and aza crown ethers, naphthalene fluorescence gets quenched. In the systems I to V, the quenching is mainly due to efficient spin-orbit coupling (SOC) leading to greater population of the lowest triplet state of naphthalene. This SOC depends on the orientation of the crown ring with respect to the Naph--plane. However, in the systems L1 and L2, the quenching is due to photoinduced electron transfer (PET) from nitrogen lone pair of the aza crown ring to naphthalene moiety and consequent exciplex formation. The results have been interpreted using the time-resolved emission studies of all the compounds in various solvents, their alkali metal ion complexes, and protonated ligands.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-03-01

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

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

    International Nuclear Information System (INIS)

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

  19. THE CM-, MM-, AND SUB-MM-WAVE SPECTRUM OF ALLYL ISOCYANIDE AND RADIOASTRONOMICAL OBSERVATIONS IN ORION KL AND THE SgrB2 LINE SURVEYS

    Energy Technology Data Exchange (ETDEWEB)

    Haykal, I.; Margulès, L.; Huet, T. R.; Motyienko, R. A. [Laboratoire de Physique des Lasers, Atomes, et Molécules, UMR CNRS 8523, Université de Lille 1, F-59655 Villeneuve d' Ascq Cédex (France); Écija, P.; Cocinero, E. J.; Basterretxea, F.; Fernández, J. A.; Castaño, F. [Departamento de Química Física, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Barrio Sarriena s/n, E-48940 Leioa (Spain); Lesarri, A. [Departamento de Química Física y Química Inorgánica, Facultad de Ciencias, Universidad de Valladolid, E-47011 Valladolid (Spain); Guillemin, J. C. [Institut des Sciences Chimiques de Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, Allèe de Beaulieu, CS 50837, F-35708 Rennes Cedex 7 (France); Tercero, B.; Cernicharo, J., E-mail: laurent.margules@univ-lille1.fr [Centro de Astrobiología (CSIC-INTA), Laboratory of Molecular Astrophysics, Department of Astrophysics, Ctra. De Ajalvir, km 4, E-28850 Torrejón de Ardoz, Madrid (Spain)

    2013-11-10

    Organic isocyanides have an interesting astrochemistry and some of these molecules have been detected in the interstellar medium (ISM). However, rotational spectral data for this class of compounds are still scarce. We provide laboratory spectra of the four-carbon allyl isocyanide covering the full microwave region, thus allowing a potential astrophysical identification in the ISM. We assigned the rotational spectrum of the two cis (synperiplanar) and gauche (anticlinal) conformations of allyl isocyanide in the centimeter-wave region (4-18 GHz), resolved its {sup 14}N nuclear quadrupole coupling (NQC) hyperfine structure, and extended the measurements into the millimeter and submillimeter-wave (150-900 GHz) ranges for the title compound. Rotational constants for all the monosubstituted {sup 13}C and {sup 15}N isotopologues are additionally provided. Laboratory observations are supplemented with initial radioastronomical observations. Following analysis of an extensive dataset (>11000 rotational transitions), accurate ground-state molecular parameters are reported for the cis and gauche conformations of the molecule, including rotational constants, NQC parameters, and centrifugal distortion terms up to octic contributions. Molecular parameters have also been obtained for the two first excited states of the cis conformation, with a dataset of more than 3300 lines. The isotopic data allowed determining substitution and effective structures for the title compound. We did not detect allyl isocyanide either in the IRAM 30 m line survey of Orion KL or in the PRIMOS survey toward SgrB2. Nevertheless, we provided an upper limit to its column density in Orion KL.

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

    Energy Technology Data Exchange (ETDEWEB)

    Fayolle-Guichard, F.

    2005-04-01

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

  1. Pra Rancangan Pabrik Pembuatan Shampoo Dengan Bahan Baku Sodium Layryl Ether Sulfonat Kapasitas Produksi 8.000 Ton / Tahun

    OpenAIRE

    Herri Putra

    2009-01-01

    Pabrik Shampoo ini direncanakan berproduksi dengan kapasitas 8.000 ton/tahun dengan 340 hari kerja dalam 1 (satu) tahun. Proses yang digunakan melalui 2 tahap yaitu proses pembuatan Lauryl Ether Sulfonat dan proses pembuatan shampoo. Pembuatan Lauryl Ether Sulfonat dilakukan melalui proses pencampuran Lauryl ether dengan oleum 20% di sulfonator (R-101) dengan temperatur proses 46oC sehingga terbentuk senyawa lauryl ether sulfonat. Kemudian lauryl ether sulfonat ini dinetralisasi dengan mengg...

  2. Pra Rancangan Pabrik Pembuatan Shampoo Dengan Bahan Baku Sodium Layryl Ether Sulfonat Kapasitas Produksi 10.000 Ton / Tahun

    OpenAIRE

    Muhammad Dimas Arhadiansyah

    2009-01-01

    Pabrik Shampoo ini direncanakan berproduksi dengan kapasitas 8.000 ton/tahun dengan 340 hari kerja dalam 1 (satu) tahun. Proses yang digunakan melalui 2 tahap yaitu proses pembuatan Lauryl Ether Sulfonat dan proses pembuatan shampoo. Pembuatan Lauryl Ether Sulfonat dilakukan melalui proses pencampuran Lauryl ether dengan oleum 20% di sulfonator (R-101) dengan temperatur proses 46oC sehingga terbentuk senyawa lauryl ether sulfonat. Kemudian lauryl ether sulfonat ini dinetralisasi dengan mengg...

  3. Structure formation of soil dispersions in the presence of polyelectrolytes on the basis of allyl alcohol and acryl acid derivatives

    Directory of Open Access Journals (Sweden)

    Amankait Asanov

    2015-09-01

    Full Text Available Some changes of structural composition and surface properties of soil dispersions in the presence of polyelectrolytes, based on allyl alcohol and acryl acid derivatives, have been studied. The results show, that the changes in the structure of soil dispersions composition are connected with the added concentration and pH value, that depend on mole ratio and nature of functional groups, as well as on the nature of counterions and concomitant electrolytes, changing with the conditions of polymer analogous conversion and neutralization reaction. Experimental data show, that the change in the conformational state and the length of the macromolecule has a significant impact on the structure-forming effect and the amount of polyelectrolyte, needed to achieve the same degree of structure-forming effect of soil dispersions. The causes for the revealed reasons are shown on the basis of the results of the experiment. Along with this, it was found that particular changes of structural composition and surface properties of the soil dispersions depend on the type and concentration of the added polyelectrolyte.

  4. Allyl isothiocyanate that induces GST and UGT expression confers oxidative stress resistance on C. elegans, as demonstrated by nematode biosensor.

    Directory of Open Access Journals (Sweden)

    Koichi Hasegawa

    Full Text Available BACKGROUND: Electrophilic xenobiotics and endogenous products from oxidative stresses induce the glutathione S-transferases (GSTs, which form a large family within the phase II enzymes over both animal and plant kingdoms. The GSTs thus induced in turn detoxify these external as well as internal stresses. Because these stresses are often linked to ageing and damage to health, the induction of phase II enzymes without causing adverse effects would be beneficial in slowing down ageing and keeping healthy conditions. METHODOLOGY/PRINCIPAL FINDINGS: We have tested this hypothesis by choosing allyl isothiocyanate (AITC, a functional ingredient in wasabi, as a candidate food ingredient that induces GSTs without causing adverse effects on animals' lives. To monitor the GST induction, we constructed a gst::gfp fusion gene and used it to transform Caenorhabditis elegans for use as a nematode biosensor. With the nematode biosensor, we found that AITC induced GST expression and conferred tolerance on the nematode against various oxidative stresses. We also present evidence that the transcription factor SKN-1 is involved in regulating the GST expression induced by AITC. CONCLUSIONS/SIGNIFICANCE: We show the applicability of the nematode biosensor for discovering and evaluating functional food substances and chemicals that would provide anti-ageing or healthful benefits.

  5. A dioxygenase of Pleurotus sapidus transforms (+)-valencene regio-specifically to (+)-nootkatone via a stereo-specific allylic hydroperoxidation.

    Science.gov (United States)

    Krügener, Sven; Krings, Ulrich; Zorn, Holger; Berger, Ralf G

    2010-01-01

    A selective and highly efficient allylic oxidation of the sesquiterpene (+)-valencene to the grapefruit flavour compound (+)-nootkatone was achieved with lyophilisate of the edible mushroom Pleurotus sapidus. The catalytic reaction sequence was elucidated through the identification of intermediate, (+)-valencene derived hydroperoxides. A specific staining of hydroperoxides allowed the semi-preparative isolation of two secondary (+)-valencene hydroperoxides, 6(R)-Isopropenyl-4(R),4a(S)-dimethyl-2,3,4,4a,5,6,7,8-octahydro-naphthalen-4(S)-yl-hydroperoxide and 6(R)-Isopropenyl-4(R),4a(S)-dimethyl-2,3,4,4a,5,6,7,8-octahydro-naphthalen-2(R)-yl-hydroperoxide. Chemical reduction of the biotransformation products yielded a tertiary alcohol identified as 2(R)-Isopropenyl-8(R),8a(S)-dimethyl-1,3,4,7,8,8a-hexahydro-2H-naphthalen-4a(R)-ol. This suggested a lipoxygenase-type oxidation of (+)-valencene via secondary and tertiary hydroperoxides and confirmed homology data of the key enzyme obtained previously from amino acid sequencing. PMID:19765983

  6. Statistic evaluation of cysteine and allyl alcohol as additives for Cu-Zn coatings from citrate baths

    Directory of Open Access Journals (Sweden)

    Julyana Ribeiro Garcia

    2013-04-01

    Full Text Available In the present work, cysteine and allyl alcohol were added to citrate baths as additives to Cu-Zn coatings on steel substrates. In order to verify the effects of the deposition parameters (current density, mechanical stirring speed, and additives on the coating composition, electrochemical behavior, morphology, and microstructure properties of Cu-Zn coatings, the electrodeposition of the alloy was carried out using an experimental composite design 2³, in which these parameters were considered the entry variables and the measured properties were the response variables. The confidence level was 95% and the results were shown as response surface diagrams. It was possible to verify that the current density affected the zinc content in the coating, while the coating produced from cysteine-contained bath presented the worse anticorrosive performance. In a general way, it was possible to observe that the studied parameters affected the morphology, grain size, and the electrochemical behavior of these coatings, although only a few response variables were statistically influenced by them.

  7. Statistic evaluation of cysteine and allyl alcohol as additives for Cu-Zn coatings from citrate baths

    Directory of Open Access Journals (Sweden)

    Julyana Ribeiro Garcia

    2012-01-01

    Full Text Available In the present work, cysteine and allyl alcohol were added to citrate baths as additives to Cu-Zn coatings on steel substrates. In order to verify the effects of the deposition parameters (current density, mechanical stirring speed, and additives on the coating composition, electrochemical behavior, morphology, and microstructure properties of Cu-Zn coatings, the electrodeposition of the alloy was carried out using an experimental composite design 2³, in which these parameters were considered the entry variables and the measured properties were the response variables. The confidence level was 95% and the results were shown as response surface diagrams. It was possible to verify that the current density affected the zinc content in the coating, while the coating produced from cysteine-contained bath presented the worse anticorrosive performance. In a general way, it was possible to observe that the studied parameters affected the morphology, grain size, and the electrochemical behavior of these coatings, although only a few response variables were statistically influenced by them.

  8. Synthesis, structural characterization and biological activities of organotin(IV) complexes with 5-allyl-2-hydroxy-3-methoxybenzaldehyde-4-thiosemicarbazone

    Indian Academy of Sciences (India)

    Rosenani A Haque; M A Salam

    2015-09-01

    The organotin(IV) complexes [MeSnCl(L)] (2), [BuSnCl(L)] (3), [PhSnCl(L)] (4) and [Me2Sn(L)] (5) were synthesized by reacting organotin(IV) chloride(s) with 5-allyl-2-hydroxy-3-methoxybenzaldehyde- 4-thiosemicarbazone [H2L], (1)] in presence of KOH in 1:2:1 molar ratio (metal salt: base:ligand). All the complexes have been characterized by elemental analyses, UV-Vis, FT-IR, 1H, 13C and 119Sn NMR spectral studies. The molecular structure of complex 5 has been confirmed by single crystal X-ray diffraction analysis. The ligand, H2L coordinates to Sn(IV) in thiolate form through phenoxide-O, azomethine-N and thiolate-S atoms. The C-Sn-C angle measured from coupling constant 1 (119Sn, 13C) for dimethyltin(IV) complex 5 is 123.4°. The 2 (119Sn, 1H) coupling constant values for complex 2 and 5 are 72.4 and 76.3 Hz, respectively. Proposed geometry for five coordinated Sn(IV) atom is a strongly distorted trigonal bipyramid. Biological studies were preformed in vitro against four bacterial strains which have shown better activities and potential as antibacterial agents.

  9. Fabrication of Cellulose Film with Enhanced Mechanical Properties in Ionic Liquid 1-Allyl-3-methylimidaxolium Chloride (AmimCl

    Directory of Open Access Journals (Sweden)

    Jinhui Pang

    2013-03-01

    Full Text Available More and more attention has been paid to environmentally friendly bio-based renewable materials as the substitution of fossil-based materials, due to the increasing environmental concerns. In this study, regenerated cellulose films with enhanced mechanical property were prepared via incorporating different plasticizers using ionic liquid 1-allyl-3-methylimidazolium chloride (AmimCl as the solvent. The characteristics of the cellulose films were investigated by scanning electron microscopy (SEM, atomic force microscopy (AFM, thermal analysis (TG, X-ray diffraction (XRD, 13C Solid-state cross-polarization/magic angle spinning nuclear magnetic resonance (CP/MAS NMR and tensile testing. The results showed that the cellulose films exhibited a homogeneous and smooth surface structure. It was noted that the thermal stability of the regenerated cellulose film plasticized with glycerol was increased compared with other regenerated cellulose films. Furthermore, the incorporation of plasticizers dramatically strengthened the tensile strength and improved the hydrophobicity of cellulose films, as compared to the control sample. Therefore, these notable results exhibited the potential utilization in producing environmentally friendly cellulose films with high performance properties.

  10. Spiro-fused carbohydrate oxazoline ligands: Synthesis and application as enantio-discrimination agents in asymmetric allylic alkylation.

    Science.gov (United States)

    Kraft, Jochen; Golkowski, Martin; Ziegler, Thomas

    2016-01-01

    In the present work, we describe a convenient synthesis of spiro-fused D-fructo- and D-psico-configurated oxazoline ligands and their application in asymmetric catalysis. The ligands were synthesized from readily available 3,4,5-tri-O-benzyl-1,2-O-isopropylidene-β-D-fructopyranose and 3,4,5-tri-O-benzyl-1,2-O-isopropylidene-β-D-psicopyranose, respectively. The latter compounds were partially deprotected under acidic conditions followed by condensation with thiocyanic acid to give an anomeric mixture of the corresponding 1,3-oxazolidine-2-thiones. The anomeric 1,3-oxazolidine-2-thiones were separated after successive benzylation, fully characterized and subjected to palladium catalyzed Suzuki-Miyaura coupling with 2-pyridineboronic acid N-phenyldiethanolamine ester to give the corresponding 2-pyridyl spiro-oxazoline (PyOx) ligands. The spiro-oxazoline ligands showed high asymmetric induction (up to 93% ee) when applied as chiral ligands in palladium-catalyzed allylic alkylation of 1,3-diphenylallyl acetate with dimethyl malonate. The D-fructo-PyOx ligand provided mainly the (R)-enantiomer while the D-psico-configurated ligand gave the (S)-enantiomer with a lower enantiomeric excess. PMID:26877819

  11. Influence of the antimicrobial compound allyl isothiocyanate against the Aspergillus parasiticus growth and its aflatoxins production in pizza crust.

    Science.gov (United States)

    Quiles, Juan M; Manyes, Lara; Luciano, Fernando; Mañes, Jordi; Meca, Giuseppe

    2015-09-01

    Aflatoxins (AFs) are secondary metabolites produced by different species of Aspergillus, such as Aspergillus flavus and Aspergillus parasiticus, which possess mutagenic, teratogenic and carcinogenic activities in humans. In this study, active packaging devices containing allyl isothiocyanate (AITC) or oriental mustard flour (OMF) + water were tested to inhibit the growth of A. parasiticus and AFs production in fresh pizza crust after 30 d. The antimicrobial and anti-aflatoxin activities were compared to a control group (no antimicrobial treatment) and to a group added with commercial preservatives (sorbic acid + sodium propionate). A. parasiticus growth was only inhibited after 30 d by AITC in filter paper at 5 μL/L and 10 μL/L, AITC sachet at 5 μL/L and 10 μL/L and OMF sachet at 850 mg + 850 μL of water. However, AFs production was inhibited by all antimicrobial treatments in a dose-dependent manner. More importantly, AITC in a filter paper at 10 μL/L, AITC sachet at 10 μL/L, OMF sachet at 850 mg + 850 μL of water and sorbic acid + sodium propionate at 0.5-2.0 g/Kg completely inhibited AFs formation. The use of AITC in active packaging devices could be a natural alternative to avoid the growth of mycotoxinogenic fungi in refrigerated bakery products in substitution of common commercial preservatives. PMID:26146190

  12. Dark matter, Mach's ether and the QCD vacuum

    CERN Document Server

    Cohen-Tannoudji, Gilles

    2015-01-01

    Here is proposed the idea of linking the dark matter issue, (considered as a major problem of contemporary research in physics) with two other open theoretical questions, one, almost centenary about the existence of an unavoidable ether in general relativity agreeing with the Mach's principle, and one more recent about the properties of the quantum vacuum of the quantum field theory of strong interactions, QuantumChromodynamics (QCD). According to this idea, on the one hand, dark matter and dark energy that, according to the current standard model of cosmology represent about 95% of the universe content, can be considered as two distinct forms of the Mach's ether, and, on the other hand, dark matter, as a perfect fluid emerging from the QCD vacuum could be modeled as a Bose Einstein condensate.

  13. Intrinsic Kinetics of Dimethyl Ether Synthesis from Syngas

    Institute of Scientific and Technical Information of China (English)

    Zhaoguang Nie; Hongwei Liu; Dianhua Liu; Weiyong Ying; Dingye Fang

    2005-01-01

    The intrinsic kinetics of dimethyl ether (DME) synthesis from syngas over a methanol synthesis catalyst mixed with methanol dehydration catalyst has been investigated in a tubular integral reactor at 3-7 MPa and 220-260 ℃. The three reactions including methanol synthesis from CO and H2, CO2 and H2, and methanol dehydration were chosen as the independent reactions. The L-H kinetic model was presented for dimethyl ether synthesis and the parameters of the model were obtained by using simplex method combined with genetic algorithm. The model is reliable according to statistical analysis and residual error analysis. The synergy effect of the reactions over the bifunctional catalyst was compared with the effect for methanol synthesis catalyst under the same conditions based on the model. The effects of syngas containing N2 on the reactions were also simulated.

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

    Directory of Open Access Journals (Sweden)

    Vijayakumar Thulasi

    2011-01-01

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

  15. 固相萃取-高效液相色谱-串联质谱测定水中8种双酚-二环氧甘油醚%Determination of eight bisphenol diglycidyl ethers in water by solid phase extraction-high performance liquid chromatography-tandem mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    张海婧; 林少彬

    2014-01-01

    建立了水中8种双酚-二环氧甘油醚(双酚 A 二缩水甘油醚(BADGE)及其衍生物双酚 A(3-氯-2-羟丙基)甘油醚(BADGE·HCl)、双酚 A双(3-氯-2-羟丙基)醚(BADGE·2HCl)、双酚 A(2,3-二羟丙基)甘油醚(BADGE· H2O)、双酚 A双(2,3-二羟丙基)醚(BADGE·2H2O)、双酚 A(3-氯-2-羟丙基)(2,3-二羟丙基)醚(BADGE·HCl ·H2O)和双酚 F-二环氧甘油醚(BFDGE)及其衍生物双酚 F 双(3-氯-2-羟丙基)醚(BFDGE·2HCl))的固相萃取-高效液相色谱-串联质谱( SPE-HPLC-MS/MS)测定方法。10个饮用水接触涂料样品在室温避光条件下,以超纯水浸泡(24±1)h,然后取200 mL经 C18固相萃取柱进行净化浓缩,以 C18色谱柱进行分离,以5 mmol/L醋酸铵、甲醇和水为流动相进行梯度洗脱,质谱多反应监测( MRM)模式检测,外标法定量。结果表明,8种双酚-二环氧甘油醚在0.007~5.00μg/L线性关系良好,相关系数均大于0.9990,该方法对8种双酚-二环氧甘油醚的定量限为7~91 ng/L,回收率为79.1%~101%,RSD为4.0%~12%。该方法具有灵敏度高、选择性强的特点,能够满足水中双酚-二环氧甘油醚的快速检测和准确定量。%A solid phase extraction coupled with high performance liquid chromatography-tandem mass spectrometry( SPE-HPLC-MS/MS)method was developed for the determination of eight bisphenol diglycidyl ethers,including bisphenol A diglycidyl ether( BADGE),bisphe-nol A(3-chloro-2-hydroxypropyl)glycidyl ether(BADGE·HCl),bisphenol A bis(3-chloro-2-hydroxypropyl)ether( BADGE · 2HCl),bisphenol A( 2,3-dihydroxypropyl) glycidyl ether (BADGE·H2O),bisphenol A bis(2,3-dihydroxypropyl)ether(BADGE·2H2O),bisphenol A (3-chloro-2-hydroxypropyl)(2,3-dihydroxypropyl)ether(BADGE·HCl·H2O),bisphenol F diglycidyl ether( BFDGE ) and bisphenol F bis( 3-chloro-2-hydroxypropyl ) ether( BFDGE · 2HCl)in water. A total of ten samples

  16. Synthesis and adsorption properties of chitosan-crown ether resins

    Institute of Scientific and Technical Information of China (English)

    彭长宏; 陈艺锋; 唐谟堂

    2003-01-01

    Two kinds of novel chitosan-crown ether resins, Schiff base type chitosan-benzo-15-crown-5 (CTS-B15)and chitosan-benzo-18-crown-6 (CTS-B18), were synthesized through the reaction between -NH2 in chitosan and -CHO in 4′-formyl benzo-crown ethers. Their structures were characterized by elemental analysis and FT-IR spectra analysis. The elemental analysis results show that the mass fractions of nitrogen in CTS-B15 and CTS-B18 are much lower than those of chitosan. The results of FT-IR spectra of CTS-B15 and CTS-B18 reveal that there exist characteristic peak of C= N, N-H and Ar, and characteristic peak of pyr anoside in the chain of chitosan-crown ether resins, showing that the structures of chitosan-crown ethers are as expected. The adsorption properties of CTS-B15 and CTS-B18 for Pd2+ , Cu2 + and Hg2+ were studied and the experimental results show that these adsorbents have both good adsorption characterization and especially high particular adsorption selectivity for Pd2+ when Cu2+ and Hg2+ are in coexistence, and the coefficients of selectivity of CTS-B15 and CTS-B18 for metal ions are KPd2+/cu2+ =7.56, KPd2+/Hg2+ = 68.00, Kcu2+/Hg2+ = 9.00 and KPd2+/cu2+ = 6.00, KPd2+/Hg2+ = 19. 00, Kcu2+/Hg2+ = 3.00, respectively.

  17. Photodissociation of Non-Covalent Peptide-Crown Ether Complexes

    OpenAIRE

    Wilson, Jeffrey J.; Kirkovits, Gregory J.; Sessler, Jonathan L.; Brodbelt, Jennifer S.

    2007-01-01

    Highly chromogenic 18-crown-6-dipyrrolylquinoxaline coordinates primary amines of peptides, forming non-covalent complexes that can be transferred to the gas phase by electrospray ionization. The appended chromogenic crown ether facilitates efficient energy transfer to the peptide upon ultraviolet irradiation in the gas phase, resulting in diagnostic peptide fragmentation. Collisional activated dissociation (CAD) and infrared multiphoton dissociation (IRMPD) of these non-covalent complexes re...

  18. Detonation characteristics of dimethyl ether and ethanol-air mixtures

    Science.gov (United States)

    Diakow, P.; Cross, M.; Ciccarelli, G.

    2015-05-01

    The detonation cell structure in dimethyl ether vapor and ethanol vapor-air mixtures was measured at atmospheric pressure and initial temperatures in the range of 293-373 K. Tests were carried out in a 6.2-m-long, 10-cm inner diameter tube. For more reactive mixtures, a series of orifice plates were used to promote deflagration-to-detonation transition in the first half of the tube. For less reactive mixtures prompt detonation initiation was achieved with an acetylene-oxygen driver. The soot foil technique was used to capture the detonation cell structure. The measured cell size was compared to the calculated one-dimensional detonation reaction zone length. For fuel-rich dimethyl ether mixtures the calculated reaction zone is highlighted by a temperature gradient profile with two maxima, i.e., double heat release. The detonation cell structure was interpreted as having two characteristic sizes over the full range of mixture compositions. For mixtures at the detonation propagation limits the large cellular structure approached a single-head spin, and the smaller cells approached the size of the tube diameter. There is little evidence to support the idea that the two cell sizes observed on the foils are related to the double heat release predicted for the rich mixtures. There was very little influence of initial temperature on the cell size over the temperature range investigated. A double heat release zone was not predicted for ethanol-air detonations. The detonation cell size for stoichiometric ethanol-air was found to be similar to the size of the small cells for dimethyl ether. The measured cell size for ethanol-air did not vary much with composition in the range of 30-40 mm. For mixtures near stoichiometric it was difficult to discern multiple cell sizes. However, near the detonation limits there was strong evidence of a larger cell structure similar to that observed in dimethyl ether air mixtures.

  19. The epistemic view of quantum states and the ether

    CERN Document Server

    Marchildon, L

    2005-01-01

    The idea that the wave function represents information, or knowledge, rather than the state of a microscopic object has been held to solve foundational problems of quantum mechanics. Realist interpretation schemes, like Bohmian trajectories, have been compared to the ether in pre-relativistic theories. I argue that the comparison is inadequate, and that the epistemic view of quantum states begs the question of interpretation.

  20. Synthesis of active nitroguaiacol ether derivatives of streptomycin.

    OpenAIRE

    Abad, J P; Amils, R.

    1990-01-01

    The synthesis, purification, and biological properties of nitroguaiacol ether derivatives of streptomycin and their corresponding radioactive reduced products were examined. These derivatives are biologically active against gram-positive and gram-negative eubacteria and they are also photoreactive because of the presence of the nitroguaiacol group in the molecule. We demonstrated that these derivatives can be used as streptomycin analogs in photoaffinity labeling of the macromolecular structu...