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Sample records for anisoles

  1. Catalytic Acylation of Anisole over Some Zeolites

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    4-Methoxyacetophenone(4-MAP) was synthesized by the acylation of anisole with acetic anhydride in the presence of HY zeolite.The addition of an appropriate amount of some solvent such as dichloromethane,chloroform,carbon disulfide or chlorobenzene to the reaction system can improve the yield of the acylated product to a certain extent.HY zeolite used can be recovered,and reused after being regenerated,obtaining almost the same yield of 4-MAP as the fresh zeolite.

  2. Radical chemistry in the thermal decomposition of anisole and deuterated anisoles: an investigation of aromatic growth.

    Science.gov (United States)

    Scheer, Adam M; Mukarakate, Calvin; Robichaud, David J; Ellison, G Barney; Nimlos, Mark R

    2010-09-02

    The pyrolyses of anisole (C(6)H(5)OCH(3)), d(3)-anisole (C(6)H(5)OCD(3)), and d(8)-anisole (C(6)D(5)OCD(3)) have been studied using a hyperthermal tubular reactor and photoionization reflectron time-of-flight mass spectrometer. Gas exiting the reactor is subject to an immediate supersonic expansion after a residence time of approximately 65 mus. This allows the detection of highly reactive radical intermediates. Our results confirm that the first steps in the thermal decomposition of anisole are the loss of a methyl group to form phenoxy radical, followed by ejection of a CO to form cyclopentadienyl radical (c-C(5)H(5)); C(6)H(5)OCH(3) --> C(6)H(5)O + CH(3); C(6)H(5)O --> c-C(5)H(5) + CO. At high temperatures (T(wall) = 1200 degrees C - 1300 degrees C) the c-C(5)H(5) decomposes to propargyl radical (CH(2)CCH) and acetylene; c-C(5)H(5) --> CH(2)CCH + C(2)H(2). The formation of benzene and naphthalene is demonstrated with 1 + 1 resonance-enhanced multiphoton ionization. Propargyl radical recombination is a significant benzene formation channel. However, we show the majority of benzene is formed by a ring expansion reaction of methylcyclopentadiene (C(5)H(5)CH(3)) resulting from methyl radical addition to cyclopentadienyl radical; CH(3) + c-C(5)H(5) --> C(5)H(5)CH(3) --> C(6)H(6) + 2H. The naphthalene is generated from cyclopentadienyl radical recombination; 2c-C(5)H(5) --> C(5)H(5)-C(5)H(5) --> C(10)H(8) + 2H. The respective intermediate amu 79 and 129 species associated with these reactions are detected, confirming the stepwise nature of the decompositions. These reactions are verified by pyrolysis studies of cyclopentadiene (C(5)H(6)) and C(5)H(5)CH(3) obtained from rapid thermal dissociation of the respective dimer compounds, as well as pyrolysis studies of propargyl bromide (BrCH(2)CCH).

  3. Enhanced solar light absorption of graphene by interaction with anisole

    KAUST Repository

    Kahaly, M. Upadhyay

    2014-10-01

    We study suspended graphene in contact with the organic molecule anisole to analyse the implications of the interaction for the optical absorption, using first principle calculations. Because of a weak interaction multiple orientations of the molecule with respect to the graphene sheet are possible. A substantial enhancement of the optical absorption independent of the specific orientation is observed, which is promising for energy harvesting. © 2014 Elsevier Ltd. All rights reserved.

  4. Dynamic-accumulative operation policy of continuous distillation for the purification of anisole

    Directory of Open Access Journals (Sweden)

    Wang Zhibo

    2016-03-01

    Full Text Available In the B10 isotope enrichment industry, the purification of anisole mixture makes great sense. A dynamic-accumulative operation policy of continuous distillation (DACD with repeated filling and dumping of the still is proposed for the separation of trace heavy impurities in the recycled anisole. To simulate and optimize the purification process of anisole, a mathematical model of DACD is derived, and the computer codes are developed in the MATLAB environment. Moreover, the experiment is performed in a pilot-scale distillation column. The results show that the experimental date agrees well with simulation results. DACD could solve the difficulty of flow rate control when the bottom flow rate is very small in continuous distillation. The size of the still in this operation mode is also smaller than that in batch distillation. And the yield of anisole is raised to 99.91%. In a word, DACD is especially suitable for separating trace heavy impurities from the recycled anisole.

  5. Ultrasonic and spectral studies on charge transfer complexes of anisole and certain aromatic amines

    Science.gov (United States)

    Rajesh, R.; Raj Muhamed, R.; Justin Adaikala Baskar, A.; Kannappan, V.

    2016-10-01

    Stability constants of two complexes of anisole with aniline and N-methylaniline (NMA) are determined from the measured ultrasonic velocity in n-hexane medium at four different temperatures. Acoustic and excess thermo acoustic parameters [excess ultrasonic velocity (uE), excess molar volume (VE), excess internal pressure (πiE)] are reported for these systems at four different temperatures. The trend in acoustic and excess parameters with concentration in the two systems establishes the formation of hydrogen bonded complexes between anisole and the two amines. Thermodynamic properties are computed for the two complexes from the variation in K with temperature. The formation of these complexes is also established by UV spectral method and their spectral characteristics and stability constants are determined. K values of these complexes obtained by ultrasonic and UV spectroscopic techniques agree well. Aniline forms more stable complex than N-methylaniline with anisole in n-hexane medium.

  6. Determination of the odor threshold concentrations of chlorobrominated anisoles in water.

    Science.gov (United States)

    Diaz, Alfredo; Fabrellas, Cristina; Ventura, Francesc; Galceran, M Teresa

    2005-01-26

    Trihalophenols, which are drinking water disinfection byproducts (DBPs) formed by chlorination or chloramination practices, can be biomethylated into trihalogenated anisoles. These latter compounds have traditionally been suspected of causing odor episodes in drinking water around the world. The odor threshold concentration (OTC) of mixed chlorobrominated anisoles, which were previously synthesized, was determined by flavor profile analysis (FPA) performed by an experienced panel trained to identify odors and tastes in water. The odor threshold amount (OTA) was evaluated by using a gas chromatograph equipped with olfactometry (GC-O) and electron capture detectors (ECD). FPA results for mixed chlorobromoanisoles gave a theoretical OTCs range from 2 to 30 ng/L, the 2,6-diBr-3Cl-anisole being the most odorous compound. Rubber is the general descriptor described by panelists for these compounds, although earthy and musty are the following most cited descriptors.

  7. Highly Selective Liquid-Phase Benzylation of Anisole with Solid-Acid Zeolite Catalysts

    DEFF Research Database (Denmark)

    Poreddy, Raju; Shunmugavel, Saravanamurugan; Riisager, Anders

    2015-01-01

    Zeolites were evaluated as solid acid catalysts for the liquid-phase benzylation of anisole with benzyl alcohol, benzyl bromide, and benzyl chloride at 80 °C. Among the examined zeolites, H-mordenite-10 (H-MOR-10) demonstrated particular high activity (>99 %) and excellent selectivity (>96...

  8. The cleavage of the aryl-O-CH/sub 3/ bond using anisole as a model compound

    Energy Technology Data Exchange (ETDEWEB)

    Afifi, A.I.; Hindermann, J.P.; Chornet, E.; Overend, R.P.

    1989-04-01

    The thermal decomposition of anisole as a prototype of the aryl-methyl-ether linkage of lignin and coals has been studied under supercritical conditions using tetralin as hydrogen donor solvent. The effect of homogenous Lewis acid catalysts have also been studied under the same conditions. The main reaction products are phenol, benzene, toluene and cresols. At high tetralin to anisole ratios the selectivity to phenol is almost 80% with little or no cresol production. This selective conversion can be carried out rapidly and cleanly at high temperature (>450 degrees C). Kinetic studies were undertaken using pyrolytic, donor solvent hydrogenolytic and Lewis acid catalysed regimes in the temperature range 400-500 degrees C. The kinetics of anisole decomposition in a large excess of tetralin have been found to be in good agreement with those published in the literature. The Lewis acid catalysts lower the activation energy relative to the pyrolytic and hydrogenolytic cases. The kinetic studies and their mechanistic interpretation lead to a mechanism involving surprisingly few radical species: methyl, phenoxy, phenoxymethyl and phenyl radicals. In the presence of FeCl/sub 3/, the selectivity towards phenols and cresols is enhanced, though a side reaction leads to polymerization at low (400-420 degrees C) temperatures. It is concluded that the aryl-O-methyl ether linkage in anisole can easily be broken at high temperatures, 450-500 degrees C, in supercritical hydrogen donor solvent to give phenol in high yield and selectivity. 23 refs., 4 figs., 5 tabs.

  9. Alternative sorptive extraction method for gas chromatography determination of halogenated anisoles in water and wine samples

    Energy Technology Data Exchange (ETDEWEB)

    Montes, R. [Departamento de Quimica Analitica, Nutricion y Bromatologia, Instituto de Investigacion y Analisis Alimentario, Universidad de Santiago de Compostela, Santiago de Compostela 15782 (Spain); Rodriguez, I. [Departamento de Quimica Analitica, Nutricion y Bromatologia, Instituto de Investigacion y Analisis Alimentario, Universidad de Santiago de Compostela, Santiago de Compostela 15782 (Spain)], E-mail: qnisaac@usc.es; Rubi, E.; Bollain, M.H.; Cela, R. [Departamento de Quimica Analitica, Nutricion y Bromatologia, Instituto de Investigacion y Analisis Alimentario, Universidad de Santiago de Compostela, Santiago de Compostela 15782 (Spain)

    2007-09-05

    An alternative sorptive microextraction method for the determination of five halogenated anisoles in water and wine matrices is proposed. Analytes were concentrated in an inexpensive and disposable piece of bulk polydimethylsiloxane (PDMS), desorbed with a small volume of organic solvent, and determined by gas chromatography with electron-capture detection (GC-ECD) or tandem mass spectrometry (GC-MS/MS). The influence of several factors on the efficiency of extraction and desorption steps was investigated in detail and the observed behaviour justified on the basis of thermodynamics and kinetics of the solid-phase microextraction technique. Under optimised conditions, analytes were first extracted in the headspace (HS) mode, at room temperature, for 2.5 h and then desorbed with 1 mL of n-pentane. This extract was further evaporated to 50 {mu}L. The overall extraction yield of the procedure ranged from 40 to 55% and the limits of quantification remained between 0.5 and 20 ng L{sup -1}, depending on the compound considered and the detection technique. Precision and linearity of the method were excellent for all species with both GC-ECD and GC-MS/MS detection. Matrix effects were evaluated with different water and wine samples; moreover, the suitability of the PDMS sorbent for storage of analytes, under different conditions, was demonstrated.

  10. Effect of antioxidant butylated hydroxyl anisole on the thermal or oxidative stability of sunflower oil (Helianthus Annuus) by ultrasonic

    OpenAIRE

    Murari, Satish Kumar; Shwetha, M. V.

    2015-01-01

    The aim of the current investigation was to evaluate the efficiency of butylated hydroxyl anisole (BHA) as an antioxidant in sunflower oil (Helianthus Annuus). The oxidation stability of sunflower oil have been investigated by the effects of varying amounts of BHA. The antioxidant incorporated sunflower oil system and control edible oil were subjected to heating at 180 ± 5 °C continuously for a period of 4 h per day for consecutive 4 days. The parameters used to assess the thermal degradation...

  11. Thermal-cycling-induced spectral diffusion and thermal barriers in anisole-doped cyclohexane, an unusual multiphase host-guest system.

    Science.gov (United States)

    Somoza, Mark M; Friedrich, Josef

    2006-09-28

    The host-guest system of anisole incorporated into a cyclohexane matrix was investigated in a series of hole-burning experiments. This system is unusual in that cyclohexane can freeze into coexisting solid phases. The hole-burning experiments support the existence of two crystalline phases and one disordered phase. A second surprising characteristic of this system is that the quasi-line absorption features of the spectra appear inverted at low temperature because of unexpected dominance of fluorescence and phosphorescence.

  12. Physical properties of {l_brace}anisole + n-alkanes{r_brace} at temperatures between (293.15 and 303.15) K

    Energy Technology Data Exchange (ETDEWEB)

    Al-Jimaz, Adel S. [Department of Chemical Engineering, College of Technological Studies, P.O. Box 42325, Shuwaik 70654 (Kuwait)]. E-mail: a_jimaz@yahoo.com; Al-Kandary, Jasem A. [Department of Chemical Engineering, College of Technological Studies, P.O. Box 42325, Shuwaik 70654 (Kuwait); Abdul-latif, Abdul-Haq M. [Department of Chemical Engineering, College of Technological Studies, P.O. Box 42325, Shuwaik 70654 (Kuwait); Al-Zanki, Adnan M. [Department of Chemical Engineering, College of Technological Studies, P.O. Box 42325, Shuwaik 70654 (Kuwait)

    2005-07-15

    Density {rho}, viscosity {eta}, and refractive index n {sub D}, values of {l_brace}anisole + hexane, or heptane, or octane, or nonane, or decane, or dodecane{r_brace} binary mixtures over the entire range of mole fraction at temperatures (293.15, 298.15, and 303.15) K, have been investigated at atmospheric pressure. The excess molar volume V {sup E}, has been calculated from the experimental measurements. These results were fitted to Redlich and Kister polynomial equation to estimate the binary interaction parameters. The viscosity data were correlated with equations of Grunberg and Nissan, and McAllister. The refractive indices data were used to calculate the specific refractivity R {sub 12}, and also correlated with Lorentz-Lorenz equation. While the excess molar volumes of {l_brace}anisole + hexane{r_brace} are negative, and {l_brace}anisole + heptane{r_brace} are sigmoidal S-shaped, the remaining binary mixtures are positive. The effects of n-alkanes chain length as well as the temperature on the excess molar volume have been studied. The calculated values have been qualitatively used to explain the intermolecular interaction between the mixing components.

  13. Effect of antioxidant butylated hydroxyl anisole on the thermal or oxidative stability of sunflower oil (Helianthus Annuus) by ultrasonic.

    Science.gov (United States)

    Murari, Satish Kumar; Shwetha, M V

    2016-01-01

    The aim of the current investigation was to evaluate the efficiency of butylated hydroxyl anisole (BHA) as an antioxidant in sunflower oil (Helianthus Annuus). The oxidation stability of sunflower oil have been investigated by the effects of varying amounts of BHA. The antioxidant incorporated sunflower oil system and control edible oil were subjected to heating at 180 ± 5 °C continuously for a period of 4 h per day for consecutive 4 days. The parameters used to assess the thermal degradation and oxidation properties of the oils include ultrasonic velocity, viscosity, density and peroxide value. The fatty acid compositions of the oils were measured by gas chromatography. Adiabatic compressibility, intermolecular free length, relaxation time and acoustic impedance have been calculated from experimental data. Viscosity, density and ultrasonic velocity change in control oil is from 3.72 × 10(-2) to 13.2 × 10(-2) Nsm - 2, 918 to 994 kg/m3 and 1412 to 1484 m/s respectively and in sunflower oil with 200 ppm BHA is from 3.88 × 10(-2) to 7.52 × 10(-2) Nsm - 2, 926 to 962 kg/m3 and 1418 to 1463 m/s respectively for 16 h of heat treated oil. The ultrasonic results obtained have shown reduction in thermal degradation and improvement in oxidation stability of antioxidant loaded oil in comparison to base oil. Hence, it can be recommended that sunflower oil with 200 ppm BHA can be used for frying without adverse effect on physical properties. The ultrasonic velocity can be used for assessment of stability of frying oil.

  14. Investigation of the ionization mechanism of polycyclic aromatic hydrocarbons using an ethanol/bromobenzene/chlorobenzene/anisole mixture as a dopant in liquid chromatography/atmospheric pressure photoionization mass spectrometry

    KAUST Repository

    Amad, Maan H.

    2012-09-23

    RATIONALE An ethanol-based multicomponent dopant consisting of ethanol/chlorobenzene/bromobenzene/anisole (98.975:0.1:0.9:0.025, v/v/v/v) has been used as a dopant for atmospheric pressure photoionization (APPI) of polycyclic aromatic hydrocarbons (PAHs). In this study the mechanism of ionization of PAHs assisted by the ethanol-based multicomponent dopant is investigated. METHODS The reactant background cluster ions of the ethanol-based multicomponent dopant observed in the positive ion APPI were studied. These studies were performed to investigate the mechanism behind the generation of a molecular radical cation (M +•) for PAHs by APPI assisted by the ethanol-based multicomponent dopant. Full scan and MS/MS analyses were conducted using an LTQ Orbitrap mass spectrometer. The effect of acidification of the mobile phase on the dopant cluster ion formation was also investigated. RESULTS With the ethanol-based multicomponent dopant, a single type of molecular radical cation M +• was observed for the studied PAHs. The characteristic ion signal of the multicomponent dopant mixture consisted of mainly anisole photoions at m/z 108.05697 and its adduct ions at m/z 124.05188 and 164.07061. The anisole ion response at m/z 108.05697 was stable in the presence of acetonitrile, methanol, water and 0.1% formic acid mobile phase composition. CONCLUSIONS The abundance formation of anisole photoions shows the universality of this multicomponent dopant in ionizing compounds with ionization energy ranging from 7.1-8.2 eV. Since the ionization energy of anisole is 8.2 eV and is lower than those of chlorobenzene (9.07 eV) and bromobenzene (9.0 eV), the mechanism of formation of anisole photoions even with its very minute amounts was not only governed by its photoionization by the krypton lamp photon energy (10.0 eV and 10.6 eV), but also by charge transfer from bromobenzene and chlorobenzene radical cations. PAH molecules were mainly ionized by charge transfer reaction from

  15. Hydrogen bonding in asphaltenes and coal liquids. Quarterly report, May 1, 1981-July 31, 1981. [Effects of phenols or anisole on aging of SRC blends

    Energy Technology Data Exchange (ETDEWEB)

    Li, N.C.; Jones, L.; Yaggi, N.F.

    1981-01-01

    Coal-derived liquids are very susceptible to oxidative degradation. Oxygen and temperature exert a dramatic effect on enhancing the viscosity of coal-derived fuels, and a free-radical mechanism is an obvious choice for the mechanism of this noted oxidative degradation. In the present study, several different phenols were added to blends consisting of two different ratios of SRC I and SRC II middle distillate: 20/80 and 30/70 by weight. The objective of this research is to study the effect of phenols on the aging of the SRC blends. It has been found that upon the addition of phenol itself, the original hydrogen bonding between the acidic and basic functional groups in the coal-derived liquids is apparently disrupted because the added phenol can now interact with the proton-accepting species in liquids, thus, leading to a lower viscosity. When anisole (which contains no hydroxyl group) is added instead of phenol, the effect of slowing down the aging process is much smaller. o-Phenylphenol is a hindered phenol, and the effect on the aging process is intermediate between anisole and phenol.

  16. Volumetric and ultrasonic behaviour of binary mixtures of 1-nonanol with o-cresol, m-cresol, p-cresol and anisole at T = (293.15 and 313.15) K

    Energy Technology Data Exchange (ETDEWEB)

    Bhatia, Subhash C., E-mail: bhatiasc2@rediffmail.co [Department of Chemistry, Kurukshetra University, Kurukshetra 136 119 (India); Rani, Ruman, E-mail: rumanjangra58@gmail.co [Department of Chemistry, Kurukshetra University, Kurukshetra 136 119 (India); Bhatia, Rachna, E-mail: bhatiarachna_3@rediffmail.co [Department of Chemistry, Kurukshetra University, Kurukshetra 136 119 (India); Anand, Hardeep [Department of Chemistry, Kurukshetra University, Kurukshetra 136 119 (India)

    2011-03-15

    Densities, {rho}, and speeds of sound, u, of binary liquid mixtures of 1-nonanol with o-cresol, m-cresol, p-cresol and anisole have been measured over the entire range of composition at T = (293.15 and 313.15) K and at atmospheric pressure. Using these data, the excess molar volume, V{sup E}, molar free volume, V{sub f}, parameters related to space-filling ability, V{sub f}/V, non-linearity parameters, B/A, isentropic compressibility, {kappa}{sub S}, molar isentropic compressibility, K{sub S,m}, deviation of molar isentropic compressibility, K{sub S,m}{sup E}, deviations of the speed of sound, u{sup D}, and limiting excess partial molar volume, V-bar{sub m,i}{sup E,0}, and isentropic compressibility, K-bar{sub m,i}{sup E,0}, have been calculated. The calculated excess and deviation functions have been fitted to the Redlich-Kister polynomial equations and the results analyzed in terms of molecular interactions and structural effects.

  17. 水中苯甲醚的静态与动态顶空气相色谱分析方法建立及比较%Analytical method and comparison for static and dynamic headspace gas chromatography of anisole in water

    Institute of Scientific and Technical Information of China (English)

    张燕; 钱杰峰; 刘兰侠; 赵慧琴

    2013-01-01

    目的 建立并比较水中苯甲醚的静态顶空气相色谱氢火焰检测器的方法(以下称静态顶空法)和吹扫捕集气相色谱质谱的方法(以下称动态顶空法).方法 静态顶空方法为氮气做载气,10 ml水样品加入5 g NaC1做基质改性剂,75℃高速振摇平衡30 min后,用气相色谱测定苯甲醚的含量,采用外标法定量.动态顶空法为氦气做载气,将5.0 ml水样和0.004 mg/L的内标物氟代苯注入吹脱捕集装置中,经吹扫、捕集和脱附后,用气相色谱质谱仪测定,通过苯甲醚的保留时间及质谱图与谱库中的质谱图作对照进行定性.采用内标法进行定量分析,并对两种方法的检出限、精密度、准确度进行评价.结果 测定苯甲醚静态顶空气相色谱法和动态顶空气相色谱质谱法分别在10 ~ 500 μg/L和0.5~ 60.0 μg/L范围内有良好的线性关系;线性方程分别为Y=782.150X+1.3446和Y=0.0358X-0.0209,相关系数均≥0.999;检出限分别为0.002 μg/L和0.110 μg/L;最低定量限分别为0.006 μg/L、0.350 μg/L,RSD分别在1.8% ~2.3%和2.0% ~ 3.4%之间,样品加标回收率在93%~ 101%和96% ~101%之间.结论 静态顶空气相色谱法和动态顶空气相色谱质谱法操作简单,能快速、灵敏、准确地测定水中苯甲醚的含量.%Objective To establish and compare the method of static headspace gas chromatography hydrogen flame detector (static headspace method) and purge and trap gas chromatography-mass spectrometry (dynamic headspace method) of anisole in water.Methods Nitrogen gas was used as carrier gas in the static headspace method,5 g NaC1 as matrix modifier was added into 10 ml water.The sample was balanced with high speed vibration at 75 ℃C for 30 min,and anisole was detected by gas chromatography and quantified with external standard.Helium was used as carrier gas in dynamic headspace method,5.0 ml water and 0.004 mg/L internal standard fluorobenzene was purged

  18. Pyrolysis and Oxidation Kinetics of Anisole and Phenol

    Science.gov (United States)

    1997-06-01

    opportunity later on to serve as Rob’s teaching assistant. I chose to work with Profs. Irv Glassman and Ken Brezinsky because of their obvious enthusiasm...solvents. In general, the thermochemistry for H abstraction by C6H50- is similar to the thermochemistry for the same H abstraction by H02. However, the...1965). Effects of resonance and structure on the thermochemistry of organic’peroxy radicals and the kinetics of combustion reactions. J. Am. Chem

  19. High resolution electronic spectra of anisole and anisole-water in the gas phase: hydrogen bond switching in the S1 state.

    Science.gov (United States)

    Ribblett, J W; Sinclair, W E; Borst, D R; Yi, J T; Pratt, D W

    2006-02-01

    Rotationally resolved S(1)spectrum of the complex suggests that hydrogen bond "switching" occurs when the complex absorbs light. The former O-H- - -O(CH(3)) bond is stronger in the ground (S(0)) state, whereas the latter H-O- - -H(ring) bond is stronger in the excited (S(1)) state. Dynamical consequences of this phenomenon are discussed.

  20. Effect of nisin and butylated hydroxy anisole on storage stability of buffalo meat sausage.

    Science.gov (United States)

    Sureshkumar, S; Kalaikannan, A; Dushyanthan, K; Venkataramanujam, V

    2010-06-01

    The water activity of buffalo meat sausage was adjusted to 0.88 using humectants and by heat treatment. Nisin and butylated hydroxyanisole (BHA) were added to study the shelf life of sausage. The treatments were nisin 100 ppm + BHA 100 ppm (T3); nisin 100 ppm (T2); BHA 100 ppm (T1) and control (T0) without nisin and BHA. The sausages were vacuum packaged in polyethylene terephthalate (PET-poly) pouch and stored for 7 days at ambient conditions (35 ± 2°C, 70-80% RH). The pH of sausage increased during storage whereas the moisture content was higher in treatment T1. Tyrosine value was lowest (18.1 mg%) in T3. There was no significant difference among T0 and T1. The thiobarbituric acid reactive substances (TBARS) number of T1 and T3 were lower than that of T0 and T2. Nisin and BHA together exhibited a significant inhibitory effect on total viable count, staphylococcal, streptococcal and anaerobic counts. There was no significant difference in the yeast and mould counts among T1-T3. T3 had a better appearance, flavour, texture and overall acceptability scores up to 5 days. The product (T3) was acceptable up to 5(th) day of storage at 35 ± 2°C and 70-80% RH.

  1. Dynamic headspace coupled to perevaporation for the analysis of anisoles in wine by gas chromatography-ion-trap tandem mass spectrometry.

    Science.gov (United States)

    Gómez-Ariza, J L; García-Barrera, T; Lorenzo, F

    2004-11-12

    Off-flavours in wines are mainly due to the presence of 2,4,6-trichloroanisole and other haloanisoles. The purpose of this study was to develop a method based on the coupling of dynamic headspace and perevaporation to GC-MS-MS to attain better analyte sensitivity and selectivity. The approach has been applied to the analysis of 2,6-dichloroanisole, 2,4,6-trichloroanisole and 2,4,6-tribromoanisole in various wines. For these compounds that cause taste and odour problems, the method was linear from the quantification limit to 3 ng for all the analytes with recoveries greater than 80% and satisfactory precision. Detection limits were as low as 2-36 ng l(-1).

  2. Identification of the sex pheromone of Holotrichia reynaudi.

    Science.gov (United States)

    Ward, Andrew; Moore, Chris; Anitha, V; Wightman, John; Rogers, D John

    2002-03-01

    The male attractant pheromone of the scarab beetle Holotrichia reynaudi, an agricultural pest native to southern India, was extracted from abdominal glands of females with hexane and analyzed by gas chromatography-mass spectrometry. Field testing of the candidate chemicals, indole, phenol, and anisole, both alone and as binary mixtures, led us to conclude that anisole was the major component of the sex pheromone. Neither male nor female beetles were attracted to indole or phenol on their own. Similarly, when indole and anisole were combined, the attractiveness of the solution did not increase over that obtained with anisole alone. However, combination of phenol and anisole did alter the attractiveness of anisole, with fewer male beetles attracted to the binary mixture than to anisole on its own. The behavior of female beetles was not altered by any of the chemicals tested. Anisole is also the sex pheromone of H. consanguinea, making this the first known example of two melolonthine scarabs sharing the same pheromone.

  3. 21 CFR 582.60 - Synthetic flavoring substances and adjuvants.

    Science.gov (United States)

    2010-04-01

    ... acid (equisetic acid, citridic acid, achilleic acid). Anethole (parapropenyl anisole). Benzaldehyde.... Methyl anthranilate (methyl-2-aminobenzoate). Piperonal (3,4-methylenedioxy-benzaldehyde,...

  4. Evaluation of Gravimetric Tar Determination in Particle Samples

    DEFF Research Database (Denmark)

    Hindsgaul, Claus; Henriksen, Ulrik B.; Bentzen, Jens Dall

    2000-01-01

    A comparison of tar determination of particles from a down-draft gasifier using soxhlet extractions (with anisole, dichloromethane and acetone) and pyrolysis of the particles.......A comparison of tar determination of particles from a down-draft gasifier using soxhlet extractions (with anisole, dichloromethane and acetone) and pyrolysis of the particles....

  5. EFSA Panel on food contact materials, enzymes, flavourings and processing aids (CEF); Scientific Opinion on Flavouring Group Evaluation 23, Revision 2 (FGE.23Rev2): Aliphatic, alicyclic and aromatic ethers including anisole derivatives from chemical groups 15, 16, 22, 26 and 30

    DEFF Research Database (Denmark)

    Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister

    The European Food Safety Authority (EFSA) asked the Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (the Panel) to provide scientific advice to the Commission on the implications for human health of chemically defined flavouring substances used in or on foodstuffs...... III. Ten of the substances in the present group have been reported to occur naturally in a wide range of food items. In its evaluation, the Panel as a default used the “Maximised Survey-derived Daily Intake” (MSDI) approach to estimate the per capita intakes of the flavouring substances in Europe....... However, when the Panel examined the information provided by the European Flavouring Industry on the use levels in various foods, it appeared obvious that the MSDI approach in a number of cases would grossly underestimate the intake by regular consumers of products flavoured at the use level reported...

  6. EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF); Scientific Opinion on Flavouring Group Evaluation 23, Revision 3 (FGE.23Rev3): Aliphatic, alicyclic and aromatic ethers including anisole derivatives from chemical groups 15, 16, 22, 26 and 30

    DEFF Research Database (Denmark)

    Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister;

    of the MSDI approach. Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have also been considered. Specifications including complete purity criteria and identity for the materials of commerce have been provided for all 20 candidate substances....

  7. EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF); Scientific O pinion Flavouring Group Evaluation 23, Revision 4 (FGE.23Rev4): Aliphatic, alicyclic and aromatic ethers including anisole derivatives from chemical groups 15, 16, 22, 26 and 30

    DEFF Research Database (Denmark)

    Beltoft, Vibe Meister; Binderup, Mona-Lise; Frandsen, Henrik Lauritz;

    .068, 04.069, 04.075, 04.079, 04.084, 08.127, 09.687, 13.170 and 13.200] do not give rise to safety concerns at their levels of dietary intake, estimated on the basis of the MSDI approach. Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have...... also been considered. Specifications including complete purity criteria and identity for the materials of commerce have been provided for all 21 candidate substances. © European Food Safety Authority, 2013...

  8. EFSA ; Scientific Opinion on Flavouring Group Evaluation 59, Revision 1 (FGE.59Rev1): Consideration of aliphatic and aromatic ethers evaluated by JECFA (61st meeting and 63rd meeting) structurally related to aliphatic, alicyclic and aromatic ethers including anisole derivatives evaluated by EFSA in FGE.23 Rev2 (2010)

    DEFF Research Database (Denmark)

    Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister;

    , “No safety concern at estimated levels of intake as flavouring substances” based on the MSDI approach. Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have also been considered and for two substances, are information on the composition...

  9. A QSRR Study on the Relative Retention Time of Halogenated Methyl-phenyl Ethers

    Institute of Scientific and Technical Information of China (English)

    XU Hui-Ying; YU Qing-Sen; ZOU Jian-Wei; WANG Yan-Hua; WANG Hong-Qing; CHEN Xue-Song

    2006-01-01

    Halogenated methyl-phenyl ethers (anisoles) are ubiquitous organic compounds in the environment. In the present study, geometrical optimization and electrostatic potential calculations have been performed for 42 halogenated anisoles at the HF/6-31 G* level. A number of statistically based parameters have been obtained. By multiple regression method, linear relationships between the gas-chromatographic relative retention time (RRT) and structural descriptors have been established for the training set of 32 halogenated anisoles. The result showed that the parameters derived from electrostatic potentials (ESPs) together with the molecular volume (Vmc) could be well used to express the quantitative structure-RRT relationships of halogenated anisoles. The best two-variable regression model gives a correlation coefficient of 0.980 and a standard deviation of 0.07, and the leave-one-out cross-validated correlation coefficient is 0.975. The goodness of the model has been further validated through exploring the predictive power for the testing set of 10 halogenated anisoles.

  10. Spectral characteristics of tramadol in different solvents and β-cyclodextrin

    Science.gov (United States)

    Anton Smith, A.; Manavalan, R.; Kannan, K.; Rajendiran, N.

    2009-10-01

    Effect of solvents and β-cyclodextrin on the absorption and fluorescence spectra of tramadol drug has been investigated and compared with anisole. The solid inclusion complex of tramadol with β-CD is investigated by FT-IR, 1H NMR, scanning electron microscope (SEM), DSC and semiempirical methods. The thermodynamic parameter (Δ G) of inclusion process is determined. A solvent study shows (i) the spectral behaviour of both tramadol and anisole molecules is similar to each other and (ii) the cyclohexanol group in tramadol is not effectively conjugated with anisole group. However, in β-CD, due to space restriction of the CD cavity, a weak interaction is present between the above groups in tramadol. β-Cyclodextrin studies show that tramadol forms 1:2 inclusion complex with β-CD. A mechanism is proposed for the inclusion process.

  11. 烷氧基和酚氧基取代的茂铁盐阳离子光引发剂的合成和表征%Synthesis and Characterization of Alkoxy and Phenoxy-substituted Ferrocenium Salt Cationic Photoinitiators

    Institute of Scientific and Technical Information of China (English)

    王涛; 万平玉; 马丽君

    2006-01-01

    Alkyl-substituted ferrocenium salts have limited solubility in epoxy oligomers and produce poisonous arene by photolysis. Herein, the synthesis and photoactivity of several alkoxy-substituted ferrocenium salts as long-wavelength UV light photoinitiators have been reported. [Cyclopendadien-Fe-anisole]PF6, [Cyclopendadien-Fe-anisole]BF4, [Cyclopendadien-Fe-diphenylether]PF6, [Cyclopendadien-Fe-diphenylether]BF4. and [Cyclopendadien-Fe-diethoxybenzene] PF6 for polymerization of epoxy resin were prepared through the ligand exchange reaction between one ring of ferrocene and aromatic ether. They all display good solubility and photoinitiating activities in epoxy resins.

  12. Direct milling and casting of polymer-based optical waveguides for improved transparency in the visible range

    DEFF Research Database (Denmark)

    Snakenborg, Detlef; Perozziello, Gerardo; Klank, Henning

    2006-01-01

    with integrated optical waveguides. Polymethylinethacrylate (PMMA) is dissolved in anisole and 'doped' with styrene-arcylonitrile copolymer to vary the refractive index. The doped PMMA with a higher refractive index is then spin coated onto a PMMA substrate with a lower refractive index to provide waveguide...

  13. Iodine-catalyzed thiolation of electron-rich aromatics using sulfonyl hydrazides as sulfenylation reagents.

    Science.gov (United States)

    Zhao, Xia; Li, Tianjiao; Zhang, Lipeng; Lu, Kui

    2016-01-21

    Iodine-catalyzed thiolation of electron-rich aromatics, including substituted anisole, thioanisole, phenol, toluene, and naphthalene, using sulfonyl hydrazides as sulfenylation reagents was carried out. Sulfonothioates, the products of decomposition of sulfonyl hydrazides in the presence of iodine, are proposed as the major sulfenylation species in this transformation.

  14. An Improved Method for the Preparation of Organic Monolayers of 1-Alkenes on Hydrogen-Terminated Silicon Surfaces

    NARCIS (Netherlands)

    Sieval, A.B.; Vleeming, V.; Zuilhof, H.; Sudhölter, E.J.R.

    1999-01-01

    The possibility to use dilute alkene solutions for the formation of alkene monolayers with 1-hexadecene on a hydrogen-terminated silicon(100) surface has been investigated for a variety of solvents. The resulting monolayers were analyzed by water contact angles. Anisole, n-butylbenzene, and n-decane

  15. Preparation of Arylthiocyanates Using N,N′-Dibromo-N,N′-bis(2,5-dimethylbenzenesulphonyl ethylenediamine and N,NDibromo-2,5-dimethylbenzenesulphonamide in the Presence of KSCN as a Novel Thiocyanating Reagent

    Directory of Open Access Journals (Sweden)

    Ardeshir Khazaei

    2001-02-01

    Full Text Available N-Bromosulphonamides, synthesized via direct bromination of sulphonamides, react with several types of arene substrates in the presence of KSCN to afford aryl thiocyanates. The method appears to be generally applicable to benzenoid substrates with a wide range of substituents, such as N,N-dimethylaniline, p-xylene, anisole, mesitylene and cumene.

  16. Bis-perfluoroalkylation of aromatic compounds with sodium perfluoroalkanesulfinates

    Institute of Scientific and Technical Information of China (English)

    LIU, Jin-Tao(刘金涛); LU, He-Jun(吕贺军)

    2000-01-01

    Bis-perfluoroalkylation of aromatic compounds such as dimethoxybenzenes (2,4,6), anisole (8), pyridine (10) and quinoline (13) was accomplished by reaction with excess sodium perfluoroalkanesulfinates, RFSO2Na (1), in the presence of Mn(OAc)3·2H2O under mild conditions. The reaction provides a facile method for the synthesis of bis-perfluoroalkylated aromatic compounds.

  17. Processing of C60 thin films by Matrix-Assisted Pulsed Laser Evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Canulescu, Stela; Schou, Jørgen; Fæster, Søren

    2011-01-01

    has been applied for deposition of fullerenes for the first time and we have studied the growth of thin films of solid C60. The fragmentation of C60 fullerene molecules induced by ns ablation in vacuum of a frozen anisole target with C60 was investigated by matrix-assisted laser desorption......Thin films of fullerenes (C60) were deposited onto silicon using matrix-assisted pulsed laser evaporation (MAPLE). The deposition was carried out from a frozen homogeneous dilute solution of C60 in anisole (0.67 wt%), and over a broad range of laser fluences, from 0.15 J/cm2 up to 3.9 J/cm2. MAPLE....../ionization (MALDI). Our findings show that intact fullerene films can be produced with laser fluences ranging from 0.15 J/cm2 up to 1.5 J/cm2....

  18. AC – AC Converters for UPS

    Directory of Open Access Journals (Sweden)

    Rusalin Lucian R. Păun

    2008-05-01

    Full Text Available This paper propose a new control technique forsingle – phase AC – AC converters used for a on-line UPSwith a good dynamic response, a reduced-partscomponents, a good output characteristic, a good powerfactorcorrection(PFC. This converter no needs anisolation transformer. A power factor correction rectifierand an inverter with the proposed control scheme has beendesigned and simulated using Caspoc2007, validating theconcept.

  19. Aromatic fluorine compounds. VIII. Plant growth regulators and intermediates

    Science.gov (United States)

    Finger, G.C.; Gortatowski, M.J.; Shiley, R.H.; White, R.H.

    1959-01-01

    The preparation and properties of 41 fluorophenoxyacetic acids, 4 fluorophenoxypropionic acids, 2 fluorobenzoic acids, several indole derivatives, and a number of miscellaneous compounds are described. Data are given for many intermediates such as new fluorinated phenols, anisoles, anilines and nitrobenzenes. Most of the subject compounds are related to a number of well-known herbicides or plant growth regulators such as 2,4-D, 2,4,5-T and others.

  20. Heteropoly acid encapsulated into zeolite imidazolate framework (ZIF-67) cage as an efficient heterogeneous catalyst for Friedel–Crafts acylation

    Energy Technology Data Exchange (ETDEWEB)

    Ammar, Muhammad; Jiang, Sai; Ji, Shengfu, E-mail: jisf@mail.buct.edu.cn

    2016-01-15

    A new strategy has been developed for the encapsulation of the phosphotungstic heteropoly acid (H{sub 3}PW{sub 12}O{sub 40} denoted as PTA) into zeolite imidazolate framework (ZIF-67) cage and the PTA@ZIF-67(ec) catalysts with different PTA content were prepared. The structure of the catalysts was characterized by XRD, BET, SEM, FT-IR, ICP-AES and TG. The catalytic activity and recovery properties of the catalysts for the Friedel-Crafts acylation of anisole with benzoyl chloride were evaluated. The results showed that 14.6–31.7 wt% PTA were encapsulated in the ZIF-67 cage. The PTA@ZIF-67(ec) catalysts had good catalytic activity for Friedel-Crafts acylation. The conversion of anisole can reach ~100% and the selectivity of the production can reach ~94% over 26.5 wt% PTA@ZIF-67(ec) catalyst under the reaction condition of 120 °C and 6 h. After reaction, the catalyst can be easily separated from the reaction mixture by the centrifugation. The recovered catalyst can be reused five times and the selectivity can be kept over 90%. - Graphical abstract: The PTA@ZIF-67 catalysts with different PTA content were prepared by encapsulating the PTA into ZIF-67 cage and the as-synthesized catalysts exhibited good catalytic activity for the Friedel–Craft acylation of anisole with benzoyl chloride.

  1. Development of liquid scintillator containing a zirconium complex for neutrinoless double beta decay experiment

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, Yoshiyuki, E-mail: fukuda@staff.miyakyo-u.ac.jp [Department of Physics, Miyagi University of Education, Sendai, Miyagi 980-0845 (Japan); Moriyama, Shigetaka [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Hida, Gifu 506-1205 (Japan); Ogawa, Izumi [Faculty of Engineering, Fukui University, Fukui-shi, Fukui 910-8507 (Japan)

    2013-12-21

    An organic liquid scintillator containing a zirconium complex has been developed for a new neutrinoless double beta decay experiment. In order to produce a detector that has good energy resolution (4% at 2.5 MeV) and low background (0.1counts/(t·year)) and that can monitor tons of target isotope, we chose a zirconium β-diketone complex having high solubility (over 10 wt%) in anisole. However, the absorption peak of the diketone ligand overlaps with the luminescence of anisole. Therefore, the light yield of the liquid scintillator decreases in proportion to the concentration of the complex. To avoid this problem, we synthesized a β-keto ester complex introducing –OC{sub 3}H{sub 7} or –OC{sub 2}H{sub 5} substituent groups in the β-diketone ligand, which shifted the absorption peak to around 245 nm, which is shorter than the emission peak of anisole (275 nm). However, the shift of the absorption peak depends on the polarity of the scintillation solvent. Therefore we must choose a low polarity solvent for the liquid scintillator. We also synthesized a Zr–ODZ complex, which has a high quantum yield (30%) and good emission wavelength (425 nm) with a solubility 5 wt% in benzonitrile. However, the absorption peak of the Zr–ODZ complex was around 240 nm. Therefore, it is better to use the scintillation solvent which has shorter luminescence wavelength than that of the aromatic solvent.

  2. Excess molar volumes and refractive indices of (methoxybenzene+benzene, or toluene, or o-xylene, or m-xylene, or p-xylene, or mesitylene) binary mixtures between T=(288.15 to 303.15)K

    Energy Technology Data Exchange (ETDEWEB)

    Al-Kandary, Jasem A. [Department of Chemical Engineering, College of Technological Studies, P.O. Box 42325, Shuwaikh 70654 (Kuwait)]. E-mail: jalkandary@yahoo.com; Al-Jimaz, Adel S. [Department of Chemical Engineering, College of Technological Studies, P.O. Box 42325, Shuwaikh 70654 (Kuwait); Abdul-Latif, Abdul-Haq M. [Department of Chemical Engineering, College of Technological Studies, P.O. Box 42325, Shuwaikh 70654 (Kuwait)

    2006-11-15

    Densities {rho} and refractive indices n{sub D} for (anisole+benzene, or toluene, or o-xylene, or m-xylene or p-xylene or mesitylene) binary mixtures over the entire range of mole fraction, at temperatures (288.15, 293.15, 298.15, and 303.15)K and atmospheric pressure, have been measured. The excess molar volume V{sup E} and molar refraction deviation {delta}R{sub m}, have been calculated and fitted to the Redlich-Kister polynomial relation to estimate the binary coefficients and standard errors. The excess molar volumes are positive for (anisole+mesitylene) binary mixtures and negative for (anisole+benzene, or toluene, or xylene isomers) binary mixtures at various temperatures. Partial molar volumes V-bar {sub i} and partial excess molar volumes V-bar {sub i}{sup E} have been also derived from the experimental data. The calculated values have been used to explain the dependency of intermolecular interaction between the mixing components on the alkyl substitution on benzene ring.

  3. Multicomponent mixed dopant optimization for rapid screening of polycyclic aromatic hydrocarbons using ultra high performance liquid chromatography coupled to atmospheric pressure photoionization high-resolution mass spectrometry

    KAUST Repository

    Sioud, Salim

    2012-05-04

    RATIONALE To enhance the ionization efficiencies in atmospheric pressure photoionization mass spectrometry a dopant with favorable ionization energy such as chlorobenzene is typically used. These dopants are typically toxic and difficult to mix with water-soluble organic solvents. In order to achieve a more efficient and less toxic dopant, a multicomponent mixed dopant was explored. METHODS A multicomponent mixed dopant for non-targeted rapid screening of polycyclic aromatic hydrocarbons (PAHs) was developed and optimized using ultra high performance liquid chromatography (UPLC) coupled to atmospheric pressure photoionization high-resolution mass spectrometry. Various single and multicomponent mixed dopants consisting of ethanol, chlorobenzene, bromobenzene, anisole and toluene were evaluated. RESULTS Fourteen out of eighteen PAHs were successfully separated and detected at low pg/μL levels within 5 min with high mass accuracy ≤4 ppm. The optimal mixed multicomponent dopant consisted of ethanol/chlorobenzene/bromobenzene/anisole (98.975:0.1:0.9:0.025, v/v %) and it improved the limit of detection (LOD) by 2- to 10-fold for the tested PAHs compared to those obtained with pure chlorobenzene. CONCLUSIONS A novel multicomponent dopant that contains 99% ethanol and 1% mixture of chlorobenzene, bromobenzene and anisole was found to be an effective dopant mixture to ionize PAHs. The developed UPLC multicomponent dopant assisted atmospheric pressure photoionization high-resolution mass spectrometry offered a rapid non targeted screening method for detecting the PAHs at low pg/;μL levels within a 5 min run time with high mass accuracy a;circ4 ppm. Copyright © 2012 John Wiley & Sons, Ltd.

  4. Deposition of matrix-free fullerene films with improved morphology by matrix-assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Canulescu, Stela; Schou, Jørgen; Fæster, Søren;

    2013-01-01

    Thin films of C60 were deposited by matrix-assisted pulsed laser evaporation (MAPLE) from a frozen target of anisole with 0.67 wt% C60. Above a fluence of 1.5 J/cm2 the C60 films are strongly non-uniform and are resulting from transfer of matrix-droplets containing fullerenes. At low fluence...... the fullerene molecules in the films are intact, the surface morphology is substantially improved and there are no measurable traces of the matrix molecules in the film. This may indicate a regime of dominant evaporation at low fluence which merges into the MAPLE regime of liquid ejection of the host matrix...

  5. Femtosecond fabrication of waveguide-like micro-structures in a photorefractive polymer

    Institute of Scientific and Technical Information of China (English)

    Min Gu; Tom Rodgers; Daniel Day

    2003-01-01

    In this letter, we report on, for the first time, the successful femtosecond micro-fabrication of continu-ous waveguide-like channels in the photorefractive polymer consisting of the nonlinear chromophore 2,5-dimethyl-4-(p-nitrophenylazo)anisole (DMNPAA), the photosensitive compound 2,4,7-trinitro-9-flourenone(TNF), and the plasticiser N-ethylcarbazole (ECZ) all doped in the polymer matrix poly(methyl methacry-late) (PMMA). These channels are caused by the change in refractive index as a result of the localisedheating of the polymer and therefore have an important potential for micro-photonic devices in future.

  6. Estimating the physicochemical properties of polyhalogenated aromatic and aliphatic compounds using UPPER: part 2. Aqueous solubility, octanol solubility and octanol-water partition coefficient.

    Science.gov (United States)

    Admire, Brittany; Lian, Bo; Yalkowsky, Samuel H

    2015-01-01

    The UPPER (Unified Physicochemical Property Estimation Relationships) model uses additive and non-additive parameters to estimate 20 biologically relevant properties of organic compounds. The model has been validated by Lian and Yalkowsky (2014) on a data set of 700 hydrocarbons. Recently, Admire et al. (2014) expanded the model to predict the boiling and melting points of 1288 polyhalogenated benzenes, biphenyls, dibenzo-p-dioxins, diphenyl ethers, anisoles and alkanes. In this work, 19 new group descriptors are determined and used to predict the aqueous solubilities, octanol solubilities and the octanol-water coefficients.

  7. Aggregation of the scarab beetleHolotrichia consanguinea in response to female-released pheromone suggests secondary function hypothesis for semiochemical.

    Science.gov (United States)

    Leal, W S; Yadava, C P; Vijayvergia, J N

    1996-08-01

    The pheromone system of the scarab beetleH. consanguinea, an agricultural pest native to India, was investigated by extracting abdominal glands of females with dichloromethane and ether and analyzing them by GC-MS. Indoor bioassays with the natural product separated on a silica gel column showed that males responded to the hexane-ether (80:20) fraction by displaying a clear sexual behavior. Although the indoor bioassay-oriented approach did not lead to the identification of the active compound(s), field tests of candidate chemicals-anisole, indole, and phenol-showed that beetles responded strongly to anisole. Males and females were captured in anisolebaited traps in a ratio close to 1:1. Nearly the same sex ratio was also observed in beetles captured over the time during the flight activity of the beetles in the field. Because no clear evolutionary basis exists for why competing females are attracted to the semiochemical, it was simply referred to as a "female-released pheromone."

  8. Fluorine in drug design: a case study with fluoroanisoles.

    Science.gov (United States)

    Xing, Li; Blakemore, David C; Narayanan, Arjun; Unwalla, Ray; Lovering, Frank; Denny, R Aldrin; Zhou, Huanyu; Bunnage, Mark E

    2015-04-01

    Anisole and fluoroanisoles display distinct conformational preferences, as evident from a survey of their crystal structures. In addition to altering the free ligand conformation, various degrees of fluorination have a strong impact on physicochemical and pharmacokinetic properties. Analysis of anisole and fluoroanisole matched molecular pairs in the Pfizer corporate database reveals interesting trends: 1) PhOCF3 increases log D by ~1 log unit over PhOCH3 compounds; 2) PhOCF3 shows lower passive permeability despite its higher lipophilicity; and 3) PhOCF3 does not appreciably improve metabolic stability over PhOCH3 . Emerging from the investigation, difluoroanisole (PhOCF2 H) strikes a better balance of properties with noticeable advantages of log D and transcellular permeability over PhOCF3 . Synthetic assessment illustrates that the routes to access difluoroanisoles are often more straightforward than those for trifluoroanisoles. Whereas replacing PhOCH3 with PhOCF3 is a common tactic to optimize ADME properties, our analysis suggests PhOCF2 H may be a more attractive alternative, and greater exploitation of this motif is recommended.

  9. Studies on percutaneous penetration of chemicals - Impact of storage conditions for excised human skin.

    Science.gov (United States)

    Dennerlein, Kathrin; Schneider, Désirée; Göen, Thomas; Schaller, Karl Heinz; Drexler, Hans; Korinth, Gintautas

    2013-03-01

    According to international guidelines skin penetration experiments can be carried out using freshly excised or frozen stored skin. However, this recommendation refers to data obtained in experiments with human cadaver skin. In our study, the percutaneous penetration of the occupationally relevant chemicals anisole, cyclohexanone and 1,4-dioxane was investigated for freshly excised as well as for 4 and 30 days at -20°C stored human skin using the diffusion cell technique. As indicator for the impairment of skin barrier by freezing cholesterol dissolution was determined in the solvents in exposure chambers of diffusion cells. Considering the percutaneously penetrated amounts, the following ranking was determined: 1,4-dioxane>anisole>cyclohexanone (decline to a factor of 5.9). The differences of fluxes between freshly excised and frozen stored skin (4 and 30 days) were not significant (p>0.05). Cholesterol dissolved from the skin indicates no significant differences between freshly excised and frozen stored skin. This study shows that freezing of human skin for up to 30 days does not alter the skin barrier function and the permeability of chemicals.

  10. Neurosteroid analysis by gas chromatography–atmospheric pressure photoionization–tandem mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Suominen, Tina; Haapala, Markus; Takala, Anna [Division of Pharmaceutical Chemistry, Faculty of Pharmacy, P.O. Box 56, FI-00014 University of Helsinki (Finland); Ketola, Raimo A. [Hjelt Institute, Department of Forensic Medicine, P.O. Box 40, FI-00014 University of Helsinki (Finland); Kostiainen, Risto, E-mail: Risto.Kostiainen@helsinki.fi [Division of Pharmaceutical Chemistry, Faculty of Pharmacy, P.O. Box 56, FI-00014 University of Helsinki (Finland)

    2013-09-10

    Graphical abstract: -- Highlights: •GC is interfaced with APPI–MS/MS using simple, commercially available hardware. •With chlorobenzene as dopant, trimethylsilylated steroids form abundant radical cations with minimal fragmentation in GC–APPI–MS. •The method shows good sensitivity and quantitative performance. •The product ion spectra of the TMS-derivatized steroids are similar to EI spectra. -- Abstract: A new and simple APPI interface employing commercially available hardware is used to combine GC to MS. The feasibility of the method is demonstrated in the analysis of urine samples for neurosteroids as their trimethylsilyl (TMS) derivatives. The effect of different dopants (chlorobenzene, toluene, anisole) on the ionization of the TMS derivatives was investigated. With chlorobenzene, the TMS derivatives produced intense molecular ions with minimal fragmentation, and chlorobenzene was selected as best dopant. Protonated molecules in addition to intense molecular ions were produced with toluene and anisole. The performance of the method was verified in the analysis of human urine samples. Chromatographic performance was good with peak half-widths of 3.6–4.3 s, linearity (r{sup 2} > 0.990) was acceptable, limits of detection (LODs) were in the range of 0.01–10 ng mL{sup −1}, and repeatability was good with relative standard deviations (rsd%) below 22%. The results show that the method is well suited for the determination of neurosteroids in biological samples.

  11. The effect of temperature on the catalytic conversion of Kraft lignin using near-critical water

    DEFF Research Database (Denmark)

    Nguyen, Thi Dieu Huyen; Maschietti, Marco; Åmand, Lars-Erik

    2014-01-01

    The catalytic conversion of suspended LignoBoost Kraft lignin was performed in near-critical water using ZrO2/K2CO3 as the catalytic system and phenol as the co-solvent and char suppressing agent. The reaction temperature was varied from 290 to 370 C and its effect on the process was investigated...... in a continuous flow (1 kg/h). The yields of water-soluble organics (WSO), bio-oil and char (dry lignin basis) were in the ranges of 5–11%, 69–87% and 16–22%, respectively. The bio-oil, being partially deoxygenated, exhibited higher carbon content and heat value, but lower sulphur content than lignin. The main 1......-ring aromatics (in WSO and diethylether-soluble bio-oil) were anisoles, alkylphenols, catechols and guaiacols. The results show that increasing temperature increases the yield of 1-ring aromatics remarkably, while it increases the formation of char moderately. An increase in the yields of anisoles...

  12. Studies on Excess Volume, Viscosity, and Speed of Sound of Binary Mixtures of Methyl Benzoate in Ethers at T=(303.15,308.15, and 313.15 K

    Directory of Open Access Journals (Sweden)

    M. V. Rathnam

    2013-01-01

    Full Text Available Densities, viscosities, and speed of sound have been determined at T = (303.15, 308.15, and 313.15 K for the binary mixtures of methyl benzoate with tetrahydrofuran, 1,4-dioxane, anisole, and butyl vinyl ether over the entire range of composition. Using these measured values, excess volume VE, deviation in viscosities Δη, excess Gibb’s free energy of activation for viscous flow ΔG*E, and deviation in isentropic compressibility Δks have been calculated. These calculated binary data have been fitted to Redlich-Kister equation to determine the appropriate coefficients. The values of excess volume VE and deviation in viscosities Δη are negative over the entire range of composition for all the binary systems at the studied temperatures. The behavior of these parameters with composition of the mixture has been discussed in terms of molecular interactions between the components of liquids.

  13. A Zeolite Imidazolate Framework ZIF-8 Catalyst for Friedel-Crafts Acylation

    Institute of Scientific and Technical Information of China (English)

    LienT.L.NGUYEN; Ky K.A.LE; Nam T.S.PHAN

    2012-01-01

    A zeolite imidazolate framework,ZIF-8,was synthesized and characterized by dynamic laser light scattering,X-ray powder diffraction,scanning electron microscopy,transmission electron microscopy,thermogravimetric analysis,Fourier transform infrared,atomic absorption spectrophotometry,and nitrogen adsorption measurements.The ZIF-8 was highly crystalline and porous with a surface area of over 1600 m2/g.Friedel-Crafts acylation of anisole and benzoyl chloride proceeded well in the presence of ZIF-8 (2-6 mol%) without the need for an inert atmosphere.The reaction afforded a selectivity of 93%-95% to the p-isomer.The solid catalyst can be separated from the reaction mixture by simple centrifugation and reused without significant degradation in catalytic activity.There was no leaching of active acid species into the reaction solution.

  14. Design, fabrication and charge recombination analysis of an interdigitated heterojunction nanomorphology in P3HT/PC(70)BM solar cells.

    Science.gov (United States)

    Balderrama, Victor S; Albero, Josep; Granero, Pedro; Ferré-Borrull, Josep; Pallarés, Josep; Palomares, Emilio; Marsal, Lluis F

    2015-09-07

    In this work interdigitated heterojunction photovoltaic devices were manufactured. A donor layer of P3HT nanopillars was fabricated by soft nanoimprinting using nanoporous anodic alumina templates. Subsequently, the PC70BM acceptor layer was deposited by spin coating on top of the P3HT nanopillars using a solvent that would not dissolve any of the previous material. Anisole solvent was used because it does not dissolve the bottom donor layer of nanopillars and provides a good wettability between the two materials. Charge extraction was used to determine the charge carrier densities n on the interdigitated heterojunction under operating conditions. Moreover, transient photovoltage measurements were used to find the recombination rate constant in combination with the charge carrier density. At the same time, the interdigitated structure was also compared with bulk heterojunction and bilayer solar cells manufactured with the same polymeric and fullerene materials in order to understand the recombination loss mechanisms in the ordered and disordered nanomorphologies of the active layers.

  15. Chiral cyclopentadienylruthenium sulfoxide catalysts for asymmetric redox bicycloisomerization

    Directory of Open Access Journals (Sweden)

    Barry M. Trost

    2016-06-01

    Full Text Available A full account of our efforts toward an asymmetric redox bicycloisomerization reaction is presented in this article. Cyclopentadienylruthenium (CpRu complexes containing tethered chiral sulfoxides were synthesized via an oxidative [3 + 2] cycloaddition reaction between an alkyne and an allylruthenium complex. Sulfoxide complex 1 containing a p-anisole moiety on its sulfoxide proved to be the most efficient and selective catalyst for the asymmetric redox bicycloisomerization of 1,6- and 1,7-enynes. This complex was used to synthesize a broad array of [3.1.0] and [4.1.0] bicycles. Sulfonamide- and phosphoramidate-containing products could be deprotected under reducing conditions. Catalysis performed with enantiomerically enriched propargyl alcohols revealed a matched/mismatched effect that was strongly dependent on the nature of the solvent.

  16. Determination of poly(epsilon-caprolactone) solubility parameters: application to solvent substitution in a microencapsulation process.

    Science.gov (United States)

    Bordes, C; Fréville, V; Ruffin, E; Marote, P; Gauvrit, J Y; Briançon, S; Lantéri, P

    2010-01-04

    The evolution of regulation on chemical substances (i.e. REACH regulation) calls for the progressive substitution of toxic chemicals in formulations when suitable alternatives have been identified. In this context, the method of Hansen solubility parameters was applied to identify an alternative solvent less toxic than methylene chloride used in a microencapsulation process. During the process based on a multiple emulsion (W/O/W) with solvent evaporation/extraction method, the solvent has to dissolve a polymer, poly(epsilon-caprolactone) (PCL), which forms a polymeric matrix encapsulating or entrapping a therapeutic protein as the solvent is extracted. Therefore the three partial solubility parameters of PCL have been determined by a group contribution method, swelling experiments and turbidimetric titration. The results obtained allowed us to find a solvent, anisole, able to solubilize PCL and to form a multiple emulsion with aqueous solutions. A feasibility test was conducted under standard operating conditions and allowed the production of PCL microspheres.

  17. Graphene oxide for acid catalyzed-reactions: Effect of drying process

    Science.gov (United States)

    Gong, H. P.; Hua, W. M.; Yue, Y. H.; Gao, Z.

    2017-03-01

    Graphene oxides (GOs) were prepared by Hummers method through various drying processes, and characterized by XRD, SEM, FTIR, XPS and N2 adsorption. Their acidities were measured using potentiometric titration and acid-base titration. The catalytic properties were investigated in the alkylation of anisole with benzyl alcohol and transesterification of triacetin with methanol. GOs are active catalysts for both reaction, whose activity is greatly affected by their drying processes. Vacuum drying GO exhibits the best performance in transesterification while freezing drying GO is most active for alkylation. The excellent catalytic behavior comes from abundant surface acid sites as well as proper surface functional groups, which can be obtained by selecting appropriate drying process.

  18. Síntesis y estudio fotoquímico de los derivados de 3-(E-alquenil-4-metoxifenilacetanilidas y 2-(E-alquenil-4-nitroanisoles

    Directory of Open Access Journals (Sweden)

    Neudo Urdaneta

    2013-05-01

    Full Text Available This work presents the synthesis and photochemical study of 3-(E-alkenyl-4-methoxyphenylacetanilide 3a-c and 2-(E-alkenyl-4-nitroanisole 3d-f derivatives. These compounds were prepared using the palladium catalyzed cross-coupling Suzuki-Miyaura type reaction of 4-methoxy-2-bromo-phenylacetanilide (1a, 2-bromo-4-nitro-anisol (1b and three E-1-alkenylboronic acids (2a-c. Compounds 3a and 3e were photolabile in 2-propanol. Molar extinction coefficients of 3a and 3e were 300.7M-1 cm-1 (λmax 315nm and 1505 M-1 cm-1 (λmax 295nm, respectively. Photodegradation of 3e yielded 2-methoxy-5-nitrobenzaldehyde, which was likely produced by oxidative rupture of the exocyclic double bond.

  19. Microfluidic Separation of a Soluble Substance Using Transverse Diffusion in a Layered Flow

    Directory of Open Access Journals (Sweden)

    Xuan Don Nguyen

    2016-12-01

    Full Text Available This paper presents a practical flow-through method to separate anisole and ethyl phenylacetate, respectively, from a polystyrene mixture. The microfluidic separation uses different diffusive dynamics of the substances transverse to the lamination flow formed in a microchannel. The effect of inlet flow rates and ambient temperature on separation is examined. Additionally, the possibility of the separation of the light substance from the mixture with different molecular weight is shown numerically and experimentally. The separation efficiency is explained by the facts that the relaxation time depends on the inlet flow rate and that the diffusivity depends on the ambient temperature. This method can be applied to separate monomers from aggregates.

  20. Synthesis and anti-inflammatory effects of new piperazine and ethanolamine derivatives of H(1)-antihistaminic drugs.

    Science.gov (United States)

    Ahmadi, Abbas; Khalili, Mohsen; Nafarie, Ali; Yazdani, Arash; Nahri-Niknafs, Babak

    2012-10-01

    In addition to their antihistamine effects, H1-receptor antagonists possess pharmacological properties that are not uniformly distributed among this class of drugs, such as anti-inflammatory, anti-allergic and antiplatelet activities. In this paper, Cyclizine (1-benzhydryl-4-methyl-piperazine, I), bromodiphenhydramine (2-[(4-bromophenyl)-phenylmethoxy]-N, N-dimethylethanamine, II) and some of their new piperazine and ethanolamine derivatives (III-VIII) inducing changes in substitution of phenyl and amine moieties were synthesized and their acute and chronic antiinflammatory effects were evaluated by standard pharmacological tests. The results showed that substitution of phenyl by tolyl, anisol and cumene groups in piperazine family could remarkably decrease acute inflammation in these new drugs. Also, substitution of dimethylamine by morpholine group could not decrease this inflammation in new synthesized ethanolamine family. But the results from the cotton pellet-induced granuloma formation in rats showed that none of drugs (I-VIII) were effective to reduce the chronic inflammation.

  1. Low density solvent-based dispersive liquid-liquid microextraction for the determination of synthetic antioxidants in beverages by high-performance liquid chromatography.

    Science.gov (United States)

    Çabuk, Hasan; Köktürk, Mustafa

    2013-01-01

    A simple and efficient method was established for the determination of synthetic antioxidants in beverages by using dispersive liquid-liquid microextraction combined with high-performance liquid chromatography with ultraviolet detection. Butylated hydroxy toluene, butylated hydroxy anisole, and tert-butylhydroquinone were the antioxidants evaluated. Experimental parameters including extraction solvent, dispersive solvent, pH of sample solution, salt concentration, and extraction time were optimized. Under optimal conditions, the extraction recoveries ranged from 53 to 96%. Good linearity was observed by the square of correlation coefficients ranging from 0.9975 to 0.9997. The relative standard deviations ranged from 1.0 to 5.2% for all of the analytes. Limits of detection ranged from 0.85 to 2.73 ng mL(-1). The method was successfully applied for determination of synthetic antioxidants in undiluted beverage samples with satisfactory recoveries.

  2. SYNTHESIS AND CHARACTERIZATION OF A SILICA-SUPPORTED CARBOXYMETHYLCELLULOSE PLATINUM COMPLEX AND ITS CATALYTIC BEHAVIORS FOR HYDROGENATION OF AROMATICS

    Institute of Scientific and Technical Information of China (English)

    TANG Liming; HUANG Meiyu; JIANG Yingyan

    1996-01-01

    A silica-supported carboxymethylcellulose platinum complex (abbreviated as SiO2-CMC-Pt) has been prepared and characterized by XPS. Its catalytic properties for hydrogenation of aromatic compounds were studied. The results showed that this catalyst could catalyze the hydrogenation of phenol, anisol, p-cresol, benzene and toluene to cyclohexanol, cyclohexyl methyl ether, p-methyl cyclohexanol, cyclohexane and methylcyclohexane, respectively in 100% yield at 30℃ and 1 atm. In the hydrogenation of phenol,COO/Pt ratio in SiO2-CMC-Pt has much influence on the initial hydrogenation rate and the selectivity for the intermediate product, cyclohexanone. The highest initial rate and the highest yield of cyclohexanone both occur at COO/Pt ratio of 6. The complex is stable during the reaction and can be used repeatedly.

  3. Synthesis of ketones from biomass-derived feedstock

    Science.gov (United States)

    Meng, Qinglei; Hou, Minqiang; Liu, Huizhen; Song, Jinliang; Han, Buxing

    2017-01-01

    Cyclohexanone and its derivatives are very important chemicals, which are currently produced mainly by oxidation of cyclohexane or alkylcyclohexane, hydrogenation of phenols, and alkylation of cyclohexanone. Here we report that bromide salt-modified Pd/C in H2O/CH2Cl2 can efficiently catalyse the transformation of aromatic ethers, which can be derived from biomass, to cyclohexanone and its derivatives via hydrogenation and hydrolysis processes. The yield of cyclohexanone from anisole can reach 96%, and the yields of cyclohexanone derivatives produced from the aromatic ethers, which can be extracted from plants or derived from lignin, are also satisfactory. Detailed study shows that the Pd, bromide salt and H2O/CH2Cl2 work cooperatively to promote the desired reaction and inhibit the side reaction. Thus high yields of desired products can be obtained. This work opens the way for production of ketones from aromatic ethers that can be derived from biomass.

  4. Stabilization of 2D assemblies of silver nanoparticles by spin-coating polymers

    Science.gov (United States)

    Hu, Longyu; Pfirman, Aubrie; Chumanov, George

    2015-12-01

    Silver nanoparticles self-assembled on poly(4-vinylpyridine) modified surfaces were spin-coated with poly(methyl methacrylate), poly(butyl methacrylate) and polystyrene from anisole and toluene solutions. The polymers filled the space between the particles thereby providing stabilization of the assemblies against particle aggregation when dried or chemically modified. The polymers did not coat the top surface of the nanoparticles offering the chemical accessibility to the metal surface. This was confirmed by converting the stabilized nanoparticles into silver sulfide and gold clusters. Etching the nanoparticles resulted in crater-like polymeric structures with the cavities extending down to the underlying substrate. Electrochemical reduction of silver inside the craters was performed. The approach can be extended to other nanoparticle assemblies and polymers.

  5. Synthesis and Complexation Studies of Calix[4]crown Telomers Intermolecularly Bridged with Calixarene Segments

    Institute of Scientific and Technical Information of China (English)

    LI Haibing; TIAN Demei; CHEN Yuanyin; GAO Zhinong

    2009-01-01

    Three derivatived calix[4]crowns were condensed with calixarene segments: 2,6-bis(bromomethyl)-4-methyl-anisole (BBA) to afford their telomers TCA[4] in rational yields. The binding sites may complex metal ions or amino acids selectively. The telomers shows different metal ions selectivity in comparison with their monomers, which suggests that calixarene segment bridges play an important role in ion-binding. The liquid-liquid extraction experiment showed that telomer TCA[4]-Ⅲ was excellent receptor for zwitterionic a-amino acids and soft cations Ag+ and Pb2+. The extraction percentage of tryptophan and histidine was as high as 87.9% and 91.5%, respec-tively.

  6. Laser-assisted deposition of thin C60 films

    DEFF Research Database (Denmark)

    Schou, Jørgen; Canulescu, Stela; Fæster, Søren

    . However, organic materials are usually not well suited for direct laser irradiation, since the organic molecules may suffer from fragmentation by the laser light. We have, therefore, explored the possible fragmentation of organic molecules by attempting to produce thin films of C60 which is a strongly...... bound carbon molecule with a well-defined mass (M = 720 amu) and therefore a good, organic test molecule. C60 fullerene thin films of average thickness of more than 100 nm was produced in vacuum by matrix-assisted pulsed laser evaporation (MAPLE). A 355 nm Nd:YAG laser was directed onto a frozen target...... of the matrix material, anisole, with a concentration of 0.67 wt% C60. At laser fluences below 1.5 J/cm2, a dominant fraction of the film molecules are C60 transferred to the substrate without any fragmentation. High-resolution SEM images of MAPLE deposited films reveal large circular features on the surface...

  7. Matrix Assisted Pulsed Laser Evaporation for growth of fullerene thin films

    DEFF Research Database (Denmark)

    Canulescu, Stela; Schou, Jørgen; Fæster Nielsen, Søren

    C60 fullerene thin films of average thickness of more than 100 nm can be produced in vacuum by matrix-assisted pulsed laser evaporation (MAPLE). A 355 nm Nd:YAG laser was directed onto a frozen target of anisole with a concentration of 0.67 wt% C60. At laser fluences below 1.5 J/cm2, a dominant...... fraction of the film molecules are C60 transferred to the substrate without any fragmentation. Highresolution SEM images of MAPLE deposited films reveal large circular droplets on the surface with high amount of material concentrated at edges (Fig. 1A). These features, observed over a wide range of laser...... fluences, are caused by ejection of large matrix-fullerene liquid droplets into the gas-phase and subsequent deposition. At similar laser energies, but using an unfocused laser beam, MAPLE favours evaporation of matrix and organic molecules, resulting in production of films with smooth surfaces and minimal...

  8. Growth of thin fullerene films by matrix assisted pulsed laser evaporation

    DEFF Research Database (Denmark)

    Canulescu, Stela; Schou, Jørgen; Fæster, Søren

    C60 fullerene thin films of average thickness of more than 100 nm on silicon substrates can be produced in vacuum by matrix-assisted pulsed laser evaporation (MAPLE). A 355 nm Nd:YAG laser was directed onto a frozen target of anisole with a concentration of 0.67 wt% C60. At laser fluences below 1.......5 J/cm2 the dominant fraction of the film molecules are C60 transferred to the substrate without any fragmentation. For high fluences high-resolution SEM images of MAPLE deposited films reveal large circular features on the surface with high amount of material concentrated at edges. These features......, observed over a wide range of laser fluences, are caused by ejection of large matrix-fullerene liquid droplets into the gas-phase and subsequent deposition. At similar laser energies, but using an unfocused laser beam, MAPLE favours evaporation of matrix and organic molecules, resulting in films...

  9. Non-target screening of extractable and non-extractable organic xenobiotics in riverine sediments of Ems and Mulde Rivers, Germany.

    Science.gov (United States)

    Kronimus, Alexander; Schwarzbauer, Jan

    2007-05-01

    Subaquatic sediment samples derived form Elbe and Mulde Rivers, Germany, were analyzed for extractable and non-extractable anthropogenic organic compounds by a non-target screening approach. Applied methodologies were gas chromatography-mass spectrometry, dispersion extraction and degradation procedures, particularly alkaline and acidic hydrolysis, boron tribromide treatment, ruthenium tetroxide oxidation as well as pyrolysis and TMAH (tetramethylammonium hydroxide)-thermochemolysis. Numerous compounds were identified, including halogenated benzenes, anisoles, styrenes, alkanes, diphenylmethane derivates, anilines, phenols and diphenyl ethers. The results were interpreted with respect to compound specific modes of incorporation as well as to potential sources (e.g. municipal, agricultural, industrial). Extractable and non-extractable fractions differed significantly with respect to their qualitative and quantitative composition. For example, quantities in the extractable and non-extractable fractions of chlorinated benzenes differed up to factor 50. Among other significant results, the investigation revealed hints for a dependence of the mode of incorporation of chlorinated benzenes on their substitution pattern.

  10. Use of lycopene as a natural antioxidant in extending the shelf-life of anhydrous cow milk fat.

    Science.gov (United States)

    Siwach, Ruby; Tokas, Jayanti; Seth, Raman

    2016-05-15

    Oxidative rancidity in anhydrous cow milk fat leads to reduction in its shelf life. Use of synthetic antioxidants is prevalent in dairy industry to prevent the development of rancidity. Keeping in view the increasing demand for natural additives, the present study was carried out to explore the potential of lycopene as a natural antioxidant in anhydrous cow milk fat. Lycopene at five different levels (30, 60, 90, 120 and 150 ppm) and butylated hydroxyl anisole (200 ppm), were incorporated in anhydrous cow milk fat. Potential of lycopene extract to enhance the shelf life of anhydrous cow milk fat was evaluated by measuring Free Fatty Acids, peroxide value, Thiobarbituric Acid value and color value during 12 months of storage at ambient conditions (30°C). Lycopene significantly (pLycopene containing samples scored significantly higher in terms of sensory attributes as compared to control.

  11. “Living”/controlled radical copolymerization of N-phenylmaleimide and styrene using Fréchet-type dendritic initiators

    Institute of Scientific and Technical Information of China (English)

    ZHAO; Youliang(赵优良); JIANG; Jing(姜静); LIU; Hongwei(刘宏伟); CHEN; Chuanfu(陈传福); XI; Fu(习复)

    2002-01-01

    Polyarylether dendrons as macroinitiators for the "living"/controlled free radical copolymerization of N-phenylmaleimide (PhMI) and styrene (St) have been demonstrated. The copolymerization was carried out in bulk or anisole with CuBr/bipy catalyst at 100-130℃. It is found that the resulting copolymers possess predetermined molecular weights and narrower polydispersities (1.18 < Mw / Mn < 1.32). The effects of reaction temperature and monomer feed on the copolymerization kinetics were investigated in detail. By using the Fineman-Ross method, the apparent monomer reactivity ratios for the atom transfer radical copolymerization of PhMI and St were determined to be rPhMI = 0.0207, and rSt = 0.0484, respectively.

  12. A Novel Non-phosgene Process for the Synthesis of Methyl N-Phenyl Carbamate from Methanol and Phenylurea:Effect of Solvent and Catalyst

    Institute of Scientific and Technical Information of China (English)

    WANG,Xin-Kui(王心葵); YAN,Shi-Run(闫世润); CAO,Yong(曹勇); FAN,Kang-Nian(范康年); HE,He-Yong(贺鹤勇); KANG,Mao-Qing(亢茂青); PENG,Shao-Yi(彭少逸)

    2004-01-01

    A novel environmentally benign process for the synthesis of methyl N-phenyl carbamate (MPC) from methanol and phenylurea was studied. Effect of solvent and catalyst on the reaction behavior was investigated. The IR spectra of methanol and phenylurea dissolved in different solvents were also recorded. Compared with use of methanol as both a reactant and a solvent, phenylurea conversion and selectivity to MPC increased by using toluene, benzene or anisole as a solvent, while phenylurea conversion decreased slightly by using n-octane as a solvent. The phenylurea conversion declined nearly 50% when dimethyl sulfoxide (DMSO) was used as a reaction media, and MPC selectivity decreased as well. The catalytic reaction tests showed that a basic catalyst enhanced the selectivity to MPC while an acidic catalyst promoted the formation of methyl carbamate and aniline. Moderate degree of basicity showed the best catalytic performance in the cases studied.

  13. Chiral cyclopentadienylruthenium sulfoxide catalysts for asymmetric redox bicycloisomerization

    Science.gov (United States)

    Ryan, Michael C; Rao, Meera

    2016-01-01

    Summary A full account of our efforts toward an asymmetric redox bicycloisomerization reaction is presented in this article. Cyclopentadienylruthenium (CpRu) complexes containing tethered chiral sulfoxides were synthesized via an oxidative [3 + 2] cycloaddition reaction between an alkyne and an allylruthenium complex. Sulfoxide complex 1 containing a p-anisole moiety on its sulfoxide proved to be the most efficient and selective catalyst for the asymmetric redox bicycloisomerization of 1,6- and 1,7-enynes. This complex was used to synthesize a broad array of [3.1.0] and [4.1.0] bicycles. Sulfonamide- and phosphoramidate-containing products could be deprotected under reducing conditions. Catalysis performed with enantiomerically enriched propargyl alcohols revealed a matched/mismatched effect that was strongly dependent on the nature of the solvent. PMID:27559366

  14. Degradation of various alkyl ethers by alkyl ether-degrading Actinobacteria isolated from activated sludge of a mixed wastewater treatment.

    Science.gov (United States)

    Kim, Yong-Hak; Cha, Chang-Jun; Engesser, Karl-Heinrich; Kim, Sang-Jong

    2008-11-01

    Various substrate specificity groups of alkyl ether (AE)-degrading Actinobacteria coexisted in activated sewage sludge of a mixed wastewater treatment. There were substrate niche overlaps including diethyl ether between linear AE- and cyclic AE-degrading strains and phenetole between monoalkoxybenzene- and linear AE-degrading strains. Representatives of each group showed different substrate specificities and degradation pathways for the preferred substrates. Determining the rates of initial reactions and the initial metabolite(s) from whole cell biotransformation helped us to get information about the degradation pathways. Rhodococcus sp. strain DEE5311 and Rhodococcus rhodochrous strain 117 both were able to degrade anisole and phenetole through aromatic 2-monooxygenation to form 2-alkoxyphenols. In contrast, diethyl ether-oxidizing strain DEE5311 capable of degrading a broad range of linear AE, dibenzyl ether and monoalkoxybenzenes initially transformed anisole and phenetole to phenol via direct O-dealkylation. Compared to this, cyclic AE-degrading Rhodococcus sp. strain THF100 preferred tetrahydrofuran (265 ± 35 nmol min(-1)mg(-1) protein) to diethyl ether (diethoxybenzene-degrading Rhodococcus sp. strain DEOB100 and Gordonia sp. strain DEOB200 transformed 1,3-/1,4-dialkoxybenzenes to 3-/4-alkoxyphenols by similar manners in the order of rates (nmol min(-1) mg(-1) protein): 1,4-diethoxybenzene (11.1 vs. 3.9)>1,4-dimethoxybenzene (1.6 vs. 2.6)>1,3-dimethoxybenzene (0.6 vs. 0.6). This study suggests that the AE-degrading Actinobacteria can orchestrate various substrate specificity responses to the degradation of various categories of AE pollutants in activated sludge communities.

  15. 三丁基锡/SBA-15功能配合物的合成、表征及对Friedel-Crafts反应的选择性催化%Synthesis, Characterization and Catalytic Performance Toward the Friedel-Crafts Acylation of Tributyltin Functionalized SBA-15

    Institute of Scientific and Technical Information of China (English)

    荆涛; 覃志乐; 宋伟明; 赵云鹏; 邓启刚

    2013-01-01

    将三丁基氯化锡与SBA-15介孔分子筛在N2气气氛中进行回流反应,得到有机锡无机配合物(C4H9)3Sn-O-SBA-15[Bu3SnS].利用X射线衍射(XRD)、透射电子显微镜(TEM)、氮气吸附脱附、固体核磁(NMR)和吡啶吸附脱附红外光谱分析(Py-IR)等方法对产物的组成、结构和性质进行了表征.结果表明,产物Bu3 SnS具有高度有序的六方介孔结构,与SBA-15相比,Bu3 SnS比表面积、孔容和孔径变小,酸性增强.Bu3 SnS对苯甲醚Friedel-Crafts酰基化反应具有优异的催化性能,当反应温度为130℃,n(苯甲醚)∶n(苯甲酰氯)=1.0∶2.0,w(cat) =6%(相对于苯甲醚用量),反应时间为5h,苯甲醚的转化率达到76.0%,对甲氧基二苯酮(p-MBP)选择性达到97.8%.%The organotin inorganic complexes (C4H9) 3Sn-O-SBA-15 [Bu3SnS] were successfully synthesized by grafting tributyhin on SBA-15 mesoporous molecular sieves in a nitrogen atmosphere.The composition,structure and properties of the samples were characterized by X-ray diffraction (XRD),transmittance electron microscopy(TEM),Hammett indicator method,N2 adsorption-desorption,solid nuclear magnetic resonance (NMR),in-situ pyridine infrared spectroscopy(Py-IR) and so on.The results show that the hexagonal P6mm mesostructure of parent siliceous SBA-15 is maintained in Bu3SnS.The surface areas,proe size and volume of Bu3 SnS are all deceased with the increase of acidity,compared to those of SBA-15.Friedel-Crafts acylation of anisole and benzoyl chloride can be efficiently catalyzed in the presence of Bu3 SnS.The reaction conversion of anisole and the selectivity ofp-benzoylanisole are 76.0% and 97.8%,respectively,when the molar ratio of anisole to benzoyl chloride is 0.5∶ 1.0,the amount of catalyst is 6%,the reaction temperature is 130 ℃ and the reaction time is 5 h.

  16. Design, fabrication and charge recombination analysis of an interdigitated heterojunction nanomorphology in P3HT/PC70BM solar cells

    Science.gov (United States)

    Balderrama, Victor S.; Albero, Josep; Granero, Pedro; Ferré-Borrull, Josep; Pallarés, Josep; Palomares, Emilio; Marsal, Lluis F.

    2015-08-01

    In this work interdigitated heterojunction photovoltaic devices were manufactured. A donor layer of P3HT nanopillars was fabricated by soft nanoimprinting using nanoporous anodic alumina templates. Subsequently, the PC70BM acceptor layer was deposited by spin coating on top of the P3HT nanopillars using a solvent that would not dissolve any of the previous material. Anisole solvent was used because it does not dissolve the bottom donor layer of nanopillars and provides a good wettability between the two materials. Charge extraction was used to determine the charge carrier densities n on the interdigitated heterojunction under operating conditions. Moreover, transient photovoltage measurements were used to find the recombination rate constant in combination with the charge carrier density. At the same time, the interdigitated structure was also compared with bulk heterojunction and bilayer solar cells manufactured with the same polymeric and fullerene materials in order to understand the recombination loss mechanisms in the ordered and disordered nanomorphologies of the active layers.In this work interdigitated heterojunction photovoltaic devices were manufactured. A donor layer of P3HT nanopillars was fabricated by soft nanoimprinting using nanoporous anodic alumina templates. Subsequently, the PC70BM acceptor layer was deposited by spin coating on top of the P3HT nanopillars using a solvent that would not dissolve any of the previous material. Anisole solvent was used because it does not dissolve the bottom donor layer of nanopillars and provides a good wettability between the two materials. Charge extraction was used to determine the charge carrier densities n on the interdigitated heterojunction under operating conditions. Moreover, transient photovoltage measurements were used to find the recombination rate constant in combination with the charge carrier density. At the same time, the interdigitated structure was also compared with bulk heterojunction and

  17. Influence of polymer:sensitizer ratio on photoelectric properties of organic composite photoconductor

    Science.gov (United States)

    Aleman, K.; Sanchez Juarez, A.; Kosarev, A.; Mansurova, S.; Koeber, S.; Meerholz, K.

    2010-06-01

    The results on characterization of the main photoelectric properties of the polymer:fulleren based composite material by using the non-steady-state photo-electromotive force (p-EMF) and modulated photocurrent technique are presented. By measuring this current under different experimental conditions, important material photoelectric parameters such as drift L0 and diffusion length LD, photocarrier's lifetime τ ; quantum efficiency of charge generation φ can be determined. The 50% of the composite weight consists of a mixture of the hole-conducting polymer PF6:TPD (poly-hexyle-triophene:N,N'-bis(4-methylphenyl)-N,N'-bis-(phenyl)-benzidine) sensitized with the highly soluble C60 derivative PCBM (phenyl-C61-butyric acid methyl ester) . Seven samples with varied polymer:sensitizer weight ratio (49:1wt.-%, 45:5wt.-%, 40:10wt.-%, 15:35wt.-%, 25:25wt.-%, 10:40wt.-%, 5:45wt.-%) where prepared. The remaining 50% were two azo-dyes 2,5-dimethyl-(4-p-nitrophenylazo)-anisole (DMNPAA) and 3- methoxy-(4-p-nitrophenylazo)-anisole (MNPAA) (25wt.-% each). Photoconductive composite film was sandwiched between two glass plates covered by transparent ITO electrodes. Two counter-propagating beams derived from a cw HeNe laser (λ = 633nm) intersected inside the detector creating an interference pattern. The output photo-EMF current (SEE MANUSCRIPT FOR EQUATION) was detected as a voltage drop by a lock-in amplifier. At polymer sensitizer ratio 25:25wt.-% the signal sign changes to the opposite revealing that the majority carriers at this and higher concentration of sensitizer are electrons. Our results show that the majority carrier's lifetime τ is only slightly affected by the variations of sensitizer concentration. Mobility-lifetime product μhτh of holes, on its turn decreases at the increasing sensitizer concentration, while μeτe of electrons keeps increasing. All this indicates that the carrier's mobility is strongly influenced by the changes on sensitizer concentrations.

  18. Low-pressure effective fluorescence lifetimes and photo-physical rate constants of one- and two-ring aromatics

    Science.gov (United States)

    Benzler, Thorsten; Faust, Stephan; Dreier, Thomas; Schulz, Christof

    2015-12-01

    One- and two-ring aromatics such as toluene and naphthalene are frequently used molecular tracer species in laser-induced fluorescence (LIF) imaging diagnostics. Quantifying LIF signal intensities requires knowledge of the photo-physical processes that determine the fluorescence quantum yield. Collision-induced and intramolecular energy transfer processes in the excited electronic state closely interact under practical conditions. They can be separated through experiments at variable low pressures. Effective fluorescence lifetimes of gaseous toluene, 1,2,4-trimethylbenzene, anisole, naphthalene, and 1-methylnaphthalene diluted in CO2 were measured after picosecond laser excitation at 266 nm and time-resolved detection of fluorescence intensities. Measurements in an optically accessible externally heated cell between 296 and 475 K and 0.010-1 bar showed that effective fluorescence lifetimes generally decrease with temperature, while the influence of the bath-gas pressure depends on the respective target species and temperature. The results provide non-radiative and fluorescence rate constants and experimentally validate the effect of photo-induced cooling.

  19. Preparation of Mg-Al layered double hydroxides intercalated with 1,3,6-naphthalenetrisulfonate and 3-amino-2,7-naphthalenedisulfonate and assessment of their selective uptake of aromatic compounds from aqueous solutions

    Science.gov (United States)

    Kameda, Tomohito; Yamazaki, Takashi; Yoshioka, Toshiaki

    2010-05-01

    Mg-Al layered double hydroxides (Mg-Al LDHs) intercalated with 1,3,6-naphthalenetrisulfonate (NTS 3-) and 3-amino-2,7-naphthalenedisulfonate (ANDS 2-) ions were prepared by coprecipitation and were characterized by X-ray diffraction and chemical analyses. Based on X-ray diffraction patterns, the naphthalene rings of NTS 3- and ANDS 2- were most likely oriented parallel to the brucite-like host layers of the Mg-Al LDH, midway between layers. The prepared Mg-Al LDHs were able to selectively take up aromatics from aqueous solutions, and the order of percentage uptake was as follows: 1,3-dinitrobenzene > nitrobenzene > benzaldehyde > N,N-dimethylaniline > anisole > 1,2-dimethoxybenzene. The differences in the extent of π-π stacking interactions occurring between the benzene rings of the aromatics and the naphthalene ring of the intercalated NTS 3- and ANDS 2- probably resulted in these differences among the absorbed quantities of the various aromatics.

  20. Reactivity of phenolic compounds towards free radicals under in vitro conditions.

    Science.gov (United States)

    Mathew, Sindhu; Abraham, T Emilia; Zakaria, Zainul Akmar

    2015-09-01

    The free radical scavenging activity and reducing power of 16 phenolic compounds including four hydroxycinnamic acid derivatives namely ferulic acid, caffeic acid, sinapic acid and p-coumaric acid, benzoic acid and its derivatives namely protocatechuic acid, gallic acid and vanillic acid, benzene derivatives namely vanillin, vanillyl alcohol, veratryl alcohol, veratraldehyde, pyrogallol, guaiacol and two synthetic antioxidants, butylated hydroxy anisole (BHA) and propyl gallate were evaluated using 1,1-Diphenyl-2-picrylhydrazyl radical (DPPH(•)), 2,2'-Azinobis-3- ethylbenzothiazoline-6-sulfonic acid radical (ABTS(+•)), Hydroxyl radical ((•)OH) and Superoxide radical (O2 (•-)) scavenging assays and reduction potential assay. By virtue of their hydrogen donating ability, phenolic compounds with multiple hydroxyl groups such as protocatechuic acid, pyrogallol, caffeic acid, gallic acid and propyl gallate exhibited higher free radical scavenging activity especially against DPPH(•) and O2 (•-). The hydroxylated cinnamates such as ferulic acid and caffeic acid were in general better scavengers than their benzoic acid counter parts such as vanillic acid and protocatechuic acid. All the phenolic compounds tested exhibited more than 85 % scavenging due to the high reactivity of the hydroxyl radical. Phenolic compounds with multiple hydroxyl groups also exhibited high redox potential. Exploring the radical scavenging and reducing properties of antioxidants especially those which are found naturally in plant sources are of great interest due to their protective roles in biological systems.

  1. The floral scents of Nymphaea subg. Hydrocallis (Nymphaeaceae), the New World night-blooming water lilies, and their relation with putative pollinators.

    Science.gov (United States)

    Maia, Artur Campos Dália; de Lima, Carla Teixeira; Navarro, Daniela Maria do Amaral Ferraz; Chartier, Marion; Giulietti, Ana Maria; Machado, Isabel Cristina

    2014-07-01

    Night-blooming water lilies are characterized by intense emission of floral VOCs. Their unique scent-oriented pollinators, cyclocephaline scarabs (Scarabaeidae, Cyclocephalini), are attracted to flowers that they use as reliable sources of food and as mating aggregation sites. Chemical analysis of floral scent samples of seven species of Nymphaea subg. Hydrocallis established remarkably simple fragrant blends, each of which was dominated by one or two prominent compounds that alone accounted for over 95% of total scent emission. A total of 22 VOCs were identified: aliphatics (9), C5-branched chain compounds (5) and aromatics (8). Anisole was the dominant constituent in the floral scents of Nymphaea amazonum subsp. amazonum, N. amazonum subsp. pedersenii and N. tenerinervia, whereas (methoxymethyl)benzene was the most abundant VOC in samples of N. lasiophylla and N. lingulata. Flowers of N. rudgeana and N. gardneriana emitted high amounts of methyl hexanoate and methyl 2-methylbutanoate. Comparisons of floral VOC composition including other day- and night-blooming species of Nymphaea and Victoria obtained from the literature evidenced disparities related to habitus. While flowers of day-blooming species mostly emit aromatic alcohols and ethers, nocturnal species are particularly rich in aromatic ethers, aliphatic esters and C5-branched chain esters. These findings strongly suggest that the floral scent composition within closely related Nymphaea and Victoria is linked to pollinator selection, and the putative role of floral VOCs in pollinator attractiveness is discussed.

  2. Rapid odor perception in rat olfactory bulb by microelectrode array

    Institute of Scientific and Technical Information of China (English)

    Jun ZHOU; Qi DONG; Liu-jing ZHUANG; Rong LI; Ping WANG

    2012-01-01

    Responses of 302 mitral/tufted (M/T) cells in the olfactory bulb were recorded from 42 anesthetized freely breathing rats using a 16-channel microwire electrode array.Saturated vapors of four pure chemicals,anisole,carvone,citral and isoamyl acetate were applied.After aligning spike trains to the iritial phase of the inhalation after odor onset,the responses of M/T cells showed transient temporal features including excitatory and inhibitory patterns.Both odor-evoked patterns indicated that mammals recognize odors within a short respiration cycle after odor stimulus.Due to the small amount of information received from a single cell,we pooled results from all responsive M/T cells to study the ensemble activity.The firing rates of the cell ensembles were computed over 100 ms bins and population vectors were constructed.The high dimension vectors were condensed into three dimensions for visualization using principal component analysis.The trajectories of both excitatory and inhibitory cell ensembles displayed strong dynamics during odor stimulation.The distances among cluster centers were enlarged compared to those of the resting state.Thus,we presumed that pictures of odor information sent to higher brain regions were depicted and odor discrimination was completed within the first breathing cycle.

  3. Synthetic fuel combustion: pollutant formation. Soot initiation mechanisms in burning aromatics. First quarterly report, 19 September-31 December 1980

    Energy Technology Data Exchange (ETDEWEB)

    Rawlins, W. T.; Tanzawa, T.

    1981-01-01

    Although considerable progress has been made in recent years in understanding the phenomenology of soot formation in the combustion of hydrocarbon fuels, relatively little attention has been focused upon aromatic fuels of the types commonly found in coal liquids. In particular, the effects of gas-phase free radicals, formed during combustion, on the kinetics of formation of incipient soot particles have not been characterized. Accordingly, an experimental investigation of the detailed kinetics of incipient soot formation in the combustion and pyrolysis of aromatic fuels of the benzene, anisole, phenol, and pyrrole families has been initiated in order to determine soot formation mechanisms and rate parameters. The experiments will be performed in a shock tube over the temperature range 1300 to 2500 K, using multiple ultraviolet, visible, and infrared diagnostics to monitor the kinetic behavior of free radicals (such as OH), incipient soot particles, and combustion products. Experiments will be conducted with artificially enhanced concentrations of free radicals such as OH and O to determine their effects on the kinetics of soot and soot precursors. The experimental work will be supported and directed by a parallel analytical effort using a detailed mechanistic model of the chemical kinetics and dynamics of the reacting systems. In this report, the design and configuration of the experimental apparatus are described, the details of the kinetic model are outlined, and possible reaction pathways are discussed.

  4. A triplet-triplet annihilation based up-conversion process investigated in homogeneous solutions and oil-in-water microemulsions of a surfactant.

    Science.gov (United States)

    Penconi, Marta; Gentili, Pier Luigi; Massaro, Giuseppina; Elisei, Fausto; Ortica, Fausto

    2014-01-01

    The triplet-triplet annihilation based up-conversion process, involving a platinum octaethyl-porphyrin (PtOEP) as a sensitizer and tetraphenyl-pyrene (TPPy) as an emitter, has been investigated in homogeneous solutions of toluene, bromobenzene and anisole, and oil-in-water microemulsions of the TX-100 surfactant, where toluene constitutes the non-polar phase. In homogeneous solutions, the highest up-conversion quantum yield (of the order of 20%) has been achieved in toluene, being the solvent that has the lowest viscosity among those explored. The up-conversion emission from the PtOEP-TPPy pair has been then investigated in a toluene based oil-in-water microemulsion at three different concentrations of the solutes, showing quantum yields up to the order of 1%, under the same irradiation conditions, but different deoxygenating procedures. The results herein reported might represent a good starting point for a future investigation in microheterogeneous systems. An optimization of the microemulsion composition, in terms of surfactant, co-surfactant and toluene concentrations, could allow us to increase the sensitizer and emitter concentrations and set up the best operative conditions to obtain even higher up-conversion efficiencies.

  5. Seed-Assisted Synthesis of MWW-Type Zeolite with Organic Structure-Directing Agent-Free Na-Aluminosilicate Gel System.

    Science.gov (United States)

    Kamimura, Yoshihiro; Itabashi, Keiji; Kon, Yoshihiro; Endo, Akira; Okubo, Tatsuya

    2017-03-02

    The seed-assisted synthesis of zeolites without using organic structure-directing agents (OSDAs) has enabled alternative routes to the simple, environmentally friendly and low-cost production of industrially important zeolites. In this study, the successful seed-assisted synthesis of MCM-22 (MWW-type) zeolite with an OSDA-free gel is reported for the first time. MWW-type zeolites are obtained by the addition of as-synthesized MCM-22 seeds prepared with hexamethyleneimine (HMI) into OSDA-free Na-aluminosilicate gels. Based on the results of XRD, ICP-AES, NMR, N2 physisorption and NH3 -TPD, the product exhibited different features compared to those of the seeds. The H-form product can serve as a catalyst in Friedel-Crafts alkylation reaction of anisole with 1-phenylethanol, and its catalytic activity is comparable to the seeds. Furthermore, XRD, FE-SEM, TG-DTA, CHN, FT-IR and NMR analyses of products and intermediates provide insights into the role of seeds and occluded HMI, the crystallization process, and key factors for achieving seed-assisted synthesis of MWW-type zeolites with an OSDA-free gel system. The present results provide a new perspective for the economical and environmentally friendly production of MWW-type zeolites.

  6. The Impact of Processing on Antioxidant Activity of Faba Bean (Vicia faba L.

    Directory of Open Access Journals (Sweden)

    Yu-Wei Luo

    2015-02-01

    Full Text Available Antioxidant activity of 70% acetone extracts of raw and processed seeds of faba bean (Vicia faba. L was evaluated by various in vitro antioxidant assays, including total antioxidant, free radical scavenging, reducing power, metal ion chelating, &beta-carotene/linoleic acid bleaching and antihemolytic activities. The total phenolics and tannin contents were higher in the extract of seeds processed by autoclaving with 1% ash solution (3.6 and 1.9/100 g extract, respectively. In general, all the extracts of processed seeds exhibited higher activity in various antioxidant systems, when compared to raw seeds but significant differences were noticed between processing methods. The extract of seeds autoclaved with 1% sugar solution showed higher DPPH radical scavenging activity (IC507.4 mg/mL. Interestingly, the extract of dry heated seeds registered higher inhibition of hemolysis (76.8% compared to standards butylated hydroxyl anisole (BHA (61.8% and α-tocopherol (52.6% at the concentration of 500 &mug/mL.

  7. Fluorinated alcohols as promoters for the metal-free direct substitution reaction of allylic alcohols with nitrogenated, silylated, and carbon nucleophiles.

    Science.gov (United States)

    Trillo, Paz; Baeza, Alejandro; Nájera, Carmen

    2012-09-01

    The direct allylic substitution reaction using allylic alcohols in 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) and 2,2,2-trifluoroethanol (TFE) as reaction media is described. The developed procedure is simple, works under mild conditions (rt, 50 and 70 °C), and proves to be very general, since different nitrogenated nucleophiles and carbon nucleophiles can be used achieving high yields, especially when HFIP is employed as solvent and aromatic allylic alcohols are the substrates. Thus, sulfonamides, carbamates, carboxamides, and amines can be successfully employed as nitrogen-based nucleophiles. Likewise, silylated nucleophiles such as trimethylsilylazide, allyltrimethylsilane, trimethylsilane, and trimethylsilylphenylacetylene give the corresponding allylic substitution products in high yields. Good results for the Friedel-Crafts adducts are also achieved with aromatic compounds (phenol, anisole, indole, and anilines) as nucleophiles. Particularly interesting are the results obtained with electron-rich anilines, which can behave as nitrogenated or carbon nucleophiles depending on their electronic properties and the solvent employed. In addition, 1,3-dicarbonyl compounds (acetylacetone and Meldrum's acid) are also successfully employed as soft carbon nucleophiles. Studies for mechanism elucidation are also reported, pointing toward the existence of carbocationic intermediates and two working reaction pathways for the obtention of the allylic substitution product.

  8. 大豆蛋白美拉德反应产物在肉糜保鲜中的应用%Application of Soybean Protein Maillard Reaction Products in Minced Meat Storage

    Institute of Scientific and Technical Information of China (English)

    李芳菲; 郑环宇; 孔保华; 夏秀芳

    2016-01-01

    The influence of Maillard reaction products(MRPs) prepared with isolated soybean protein(SPI) on physicochemical properties in ripe minced meat was investigated by measuring thiobarbituric acid reactive sub-stanc (TBARS), a*-value, pH and sensory evaluation. Results showed that MRPs exhibited antioxidant effect in the cooked meat batter, which could inhibit the lipid oxidation, keep batter colour and a good overall ac-ceptability. Moreover, the antioxidant effect was better with more MRPs addition. In terms of colour and antioxi-dant effect, there was no significant difference between the batter with 2.0%MRPs and with 0.02%butyl hy-droxy anisole (P>0.05), however, there was a significant difference between the batter with 2.0%MRPs and the control (P0.05),与其他处理组和对照组存在显著性差异(P<0.05)。因此,大豆分离蛋白美拉德反应产物能够作为一种安全的抗氧化剂添加到熟肉糜中,提高抗氧化能力,保持感官特性,延长货架期。

  9. Baseline isotopic data of polyhalogenated compounds

    Energy Technology Data Exchange (ETDEWEB)

    Vetter, Walter [University of Hohenheim, Institute of Food Chemistry, Garbenstr. 28, D-70593 Stuttgart (Germany)]. E-mail: w-vetter@uni-hohenheim.de; Armbruster, Wolfgang [University of Hohenheim, Institute of Food Chemistry, Garbenstr. 28, D-70593 Stuttgart (Germany); Betson, Tatiana R. [Medical Biochemistry and Biophysics, Umea University, SE-901 87 Umea (Sweden); Schleucher, Juergen [Medical Biochemistry and Biophysics, Umea University, SE-901 87 Umea (Sweden); Kapp, Thomas [University of Hohenheim, Institute of Food Chemistry, Garbenstr. 28, D-70593 Stuttgart (Germany); Lehnert, Katja [University of Hohenheim, Institute of Food Chemistry, Garbenstr. 28, D-70593 Stuttgart (Germany)

    2006-09-08

    The {delta} {sup 2}H- and {delta} {sup 13}C-values of polyhalogenated compounds were determined by EA-IRMS. Most of the compounds were related to the chloropesticides DDT and its metabolites, hexachlorocyclohexanes, and toxaphene, as well as several polybrominated compounds such as bromophenols and -anisoles. {delta} {sup 2}H-values ranged between -235 per mille and +75 per mille whereas {delta} {sup 13}C-values were found in the range -22 per mille to -38 per mille . No correlation between {delta} {sup 2}H- and {delta} {sup 13}C-values could be identified. Comparative analysis clarified that bromophenols and the corresponding bromoanisoles may vary in their isotopic distribution. {sup 2}H NMR was used to quantify abundances of {sup 2}H isotopomers. Quantification of isotopomers of 2,4-dibromophenol and 2,4-dibromoanisole proved that both compounds from different suppliers do not originate from the same source. Differences in the {delta} {sup 2}H-values of two toxaphene products were further investigated by the synthesis of products of different degree of chlorination from camphene. It was shown that the {delta} {sup 13}C-values remained mostly unaltered as was expected since no carbon is lost in this procedure. However, the reaction products became enriched in {sup 2}H with increasing degree of chlorination. Different {delta} {sup 2}H-values of the starting material will also impact the {delta} {sup 2}H-values of the chlorination products.

  10. A Multifunctional and Possible Skin UV Protectant, (3R)-5-Hydroxymellein, Produced by an Endolichenic Fungus Isolated from Parmotrema austrosinense.

    Science.gov (United States)

    Zhao, Lu; Kim, Jin-Cheol; Paik, Man-Jeong; Lee, Wonjae; Hur, Jae-Seoun

    2016-12-26

    Lichens are considered a great bio-resource because they produce large numbers of secondary metabolites with many biological activities; however, they have not been cultivated under artificial conditions to date. As a result, lichen substances from natural sources are limited and have not been widely utilized in commercial applications. Accordingly, interest in lichen-associated fungi, especially endogenic fungi, has increased. Ultraviolet (UV) radiation in sunlight is harmful to human health, resulting in demand for effective UV filtering agents for use in sunscreen. In this study, we purified (3R)-5-hydroxymellein, which has UVA absorption activity, from the secondary metabolites of an endolichenic fungus (ELF000039). The antioxidant properties were then assessed by in vitro tests. The antioxidant activity of (3R)-5-hydroxymellein was high when compared to the recognized antioxidants ascorbic acid (ASA) and butyl hydroxyl anisole (BHA). Moreover, the compound exhibited no cytotoxicity toward mouse melanoma cell lines, B16F1 and B16F10, or the normal cell line, HaCaT. Furthermore, (3R)-5-hydroxymellein recovered the damage caused by UVB irradiation and inhibited melanin synthesis. Taken together, these results suggest that (3R)-5-hydroxymellein could have an interesting and vital profile to go further development as a multifunctional skin UV protectant.

  11. Using heavy atom rare gas matrix to control the reactivity of 4-methoxybenzaldehyde: A comparison with benzaldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Kus, Nihal [Department of Chemistry, University of Coimbra, 3004-535 Coimbra (Portugal); Department of Physics, Anadolu University, 26470 Eskisehir (Turkey); Sharma, Archna; Reva, Igor; Fausto, Rui [Department of Chemistry, University of Coimbra, 3004-535 Coimbra (Portugal); Lapinski, Leszek [Institute of Physics, Polish Academy of Sciences, Warsaw (Poland)

    2012-04-14

    Different patterns of photochemical behavior were observed for 4-methoxybenzaldehyde (p-anisaldehyde) isolated in xenon and in argon matrices. Monomers of the compound isolated in solid Xe decarbonylate upon middle ultraviolet irradiation, yielding methoxybenzene (anisole), and CO. On the other hand, p-anisaldehyde isolated in an Ar matrix and subjected to identical irradiation, predominantly isomerizes to the closed-ring isomeric ketene (4-methoxycyclohexa-2,4-dien-1-ylidene) methanone. Experimental detection of a closed-ring ketene photoproduct, generated from an aromatic aldehyde, constitutes a rare observation. The difference between the patterns of photochemical transformations of p-anisaldehyde isolated in argon and xenon environments can be attributed to the external heavy-atom effect, where xenon enhances the rate of intersystem crossing from the singlet to the triplet manifold in which decarbonylation (via p-methoxybenzoyl radical) takes place. The parent compound, benzaldehyde, decarbonylates (to benzene + CO) when subjected to middle ultraviolet irradiation in both argon and xenon matrices. This demonstrates the role of the methoxy p-anisaldehyde substituent in activation of the reaction channel leading to the formation of the ketene photoproduct.

  12. Conversion of solvent refined lignite into premium liquid fuels. Annual report, January-December, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Baltisberger, R.J.; Stenberg, V.I.; Klabunde, K.J.; Woolsey, N.F.

    1981-04-01

    Comparison of three preasphaltene samples separated from three lignite derived samples obtained from GFETC prepared at 404, 460 and 480/sup 0/C shows that increased temperature tends to produce higher molecular weight preasphaltene fractions containing more aromatic carbons with fewer acid (phenolic) sites per molecule. Ether cleavage studies of the model compounds; diphenyl ether, bibenzothiophene, dibenzofuran and anisole, show that partial or complete ether cleavage was obtained with sodium in hexamethyl phosphoramide solvent. Thus a careful consideration of acidity before and after cleavage can now give a measure of the diaryl ether content of a mixture. This reaction may be useful in coal liquid analysis. Denitrification of N,N-Dimethylamine without aromatic ring reduction occurs with CO-H/sub 2/O and H/sub 2/ at 425/sup 0/C in about 13% conversion. The optimum of 21 conditions gave a 19% conversion which occurs at 150 psi H/sub 2/S and 750 psi H/sub 2/. Thus, H/sub 2/S enhances nitrogen removal from this model compound. Using ESR dispersion techniques we have shown the presence of a second CO radical species on MgO, probably CO-.. observed by ESR, treatment of carbon monoxide radical species on both CO and MgO with CO/sub 2/ or H/sub 2/O causes a destruction of one of the radical species at a rate greater than that of the other.

  13. Ultrapressure liquid chromatography-tandem mass spectrometry assay using atmospheric pressure photoionization (UPLC-APPI-MS/MS) for quantification of 4-methoxydiphenylmethane in pharmacokinetic evaluation.

    Science.gov (United States)

    Farhan, Nashid; Fitzpatrick, Sean; Shim, Yun M; Paige, Mikell; Chow, Diana Shu-Lian

    2016-09-05

    4-Methoxydiphenylmethane (4-MDM), a selective augmenter of Leukotriene A4 Hydrolase (LTA4H), is a new anti-inflammatory compound for potential treatment of chronic obstructive pulmonary disease (COPD). Currently, there is no liquid chromatography tandem mass spectrometric (LC-MS/MS) method for the quantification of 4-MDM. A major barrier for developing the LC-MS/MS method is the inability of electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) to ionize 4-MDM due to its hydrophobicity and lack of any functional group for ionization. With the advent of atmospheric pressure photoionization (APPI) technique, many hydrophobic compounds have been demonstrated to ionize by charge transfer reactions. In this study, a highly sensitive ultrapressure liquid chromatography tandem mass spectrometry assay using atmospheric pressure photoionization (UPLC-APPI-MS/MS) for the quantifications of 4-MDM in rat plasma has been developed and validated. 4-MDM was extracted from the plasma by solid phase extraction (SPE) and separated chromatographically using a reverse phase C8 column. The photoionization (PI) was achieved by introducing anisole as a dopant to promote the reaction of charge transfer. The assay with a linear range of 5 (LLOQ)-400ngmL(-1) met the regulatory requirements for accuracy, precision and stability. The validated assay was employed to quantify the plasma concentrations of 4-MDM after an oral dosing in Sprague Dawley (SD) rats.

  14. Generation of active oxygen species by iron nitrilotriacetate (Fe-NTA.

    Directory of Open Access Journals (Sweden)

    Kawabata,Teruyuki

    1986-06-01

    Full Text Available Ferric nitrilotriacetate (Fe3+-NTA solution showed maximum absorbance at pH 7.5. The iron was in ferric high-spin state and coordinated octahedrally with a relatively symmetric structure and also probably pentagonally. A spin trapping technique employing 5,5-dimethyl-1-pyrroline-N-oxide (DMPO yielded a DMPO spin adduct of unknown radical with three doublets (DMPO-Z and a simple nitroxide radical (Y-NO. in serum from rats injected intraperitoneally with Fe3+-NTA. When the Fe3+-NTA solution was diluted 500-fold with 50 mM NTA solution, DMPO-Z, Y-NO. and an additional signal, DMPO-OH were observed. The DMPO-Z signal was suppressed by a decrease in oxygen tension, alpha-tocopherol and 3-tert-butyl-4-hydroxy-anisole (BHA. The DMPO-OH signal was suppressed in the presence of ethanol and catalase. Fe2+-NTA solution hardly produced DMPO spin adducts. The Fe3+-NTA solution produced a strong DMPO-OH signal in the presence of H2O2. Rose Bengal solution, a singlet oxygen generating system, produced the same DMPO adducts. Fe3+-NTA reacted with oxygen in solution. The oxygen was activated and might be similar to singlet molecular oxygen. In the presence of H2O2, the Fe3+-NTA solution generated a hydroxyl radical. Fe3+-NTA itself generated free radicals, but Fe2+-NTA did not.

  15. In vitro α-glucosidase inhibition, antioxidant, anticancer, and antimycobacterial properties of ethyl acetate extract of Aegle tamilnadensis Abdul Kader (Rutaceae) leaf.

    Science.gov (United States)

    R, Pratap Chandran; S, Nishanth Kumar; S, Manju; S, Abdul Kader; B S, Dileep Kumar

    2015-01-01

    The present study was aimed to investigate in vitro α-glucosidase inhibition, antioxidant, anticancer, and antimycobacterial activities of the ethyl acetate extract of A. tamilnadensis leaves. The extract recorded strong α-glucosidase inhibition with an IC50 value of 100 μg/ml. The antioxidant potential of the extract was evaluated by nitric oxide radical inhibition, lipid peroxidation inhibition, ferric thiocyanate, and ABTS radical scavenging assay, and the extract recorded significant antioxidant activity. The ferric thiocyanate activity of extract was superior to butylated hydroxyl anisol (BHA), the standard antioxidant agent. The anticancer activity of the extract was evaluated against (1) breast cancer cell lines (MDAM B-231), (2) cervical cancer cell lines (HeLa), and (3) lung cancer cell line (A 549) using MTT assay, and significant activity was recorded against A 549 with an IC50 value of 64 μg/ml. Further studies on the morphology, acridine orange/ethidium bromide staining, and cell cycle analysis by flow cytometry confirm the extract-induced apoptosis in A 549. This extract also recorded significant anti-tuberculosis activity against Mycobacterium smegmatis. The current study suggests that the ethyl acetate extract of A. tamilnadensis is a potential source of natural α-glucosidase inhibitor and antioxidant for protection as well as prevention of life-threatening diseases like cancer.

  16. The effect of stratification on premixed swirl-flame flashback by using porous center-body injection

    Science.gov (United States)

    McCaslin, Andrew; Ranjan, Rakesh; Clemens, Noel

    2016-11-01

    Boundary layer flashback must be prevented in order to stably operate stationary gas turbines. One strategy to avoid flashback is to create equivalence-ratio stratification, such as by reducing the fuel/air ratio in the boundary layer below the flammability limit. Typically, stratification is achieved by using radially non-uniform fuel injection. The goal of the current study is to reduce the propensity of flashback in a premixed annular swirl combustor that uses a premix section with center-body. A porous metal center-body (10 micron pore size) is used to bleed air directly into the boundary layer and thus locally reduce the equivalence ratio. Planar laser-induced fluorescence imaging of anisole-seeded flow is carried out to assess the stratification in the flow. Time-resolved PIV and chemiluminescence imaging are used to investigate flashback at atmospheric pressure conditions. A comparative study between fully premixed and stratified flame flashback is conducted to determine how stratification influences flashback physics. This work was sponsored by the DOE NETL under Grant DEFC2611-FE0007107. This source of funding is gratefully acknowledged.

  17. Growth of thin fullerene films by Matrix Assisted Pulsed Laser Evaporation

    DEFF Research Database (Denmark)

    Canulescu, Stela; Schou, Jørgen; Fæster, Søren

    . However, organic materials are usually not well suited for direct laser irradiation, since the organic molecules may suffer from fragmentation by the laser light. We have, therefore, explored the possible fragmentation of organic molecules by attempting to produce thin films of C60 which is a strongly...... bound carbon molecule with a well-defined mass (M = 720 amu) and therefore a good, organic test molecule. C60 fullerene thin films of average thickness of more than 100 nm was produced in vacuum by matrix-assisted pulsed laser evaporation (MAPLE). A 355 nm Nd:YAG laser was di-rected onto a frozen target...... of the matrix material, anisole, with a concentration of 0.67 wt% C60. At laser fluences below 1.5 J/cm2, a dominant fraction of the film molecules are C60 transferred to the substrate without any fragmentation. High-resolution SEM images of MAPLE deposited films reveal large circular features on the surface...

  18. Microextraction and Gas Chromatography/Mass Spectrometry for improved analysis of geosmin and other fungal "off" volatiles in grape juice.

    Science.gov (United States)

    Morales-Valle, H; Silva, L C; Paterson, R R M; Oliveira, J M; Venâncio, A; Lima, N

    2010-10-01

    Geosmin is a volatile fungal metabolite with an earthy aroma produced in grape products from rotten grapes. The accumulation of geosmin in grapes is caused by the interaction of Botrytis cinerea and Penicillium expansum. Solid Phase Microextraction (SPME) has great utility for collecting volatile compounds in wine. However, contamination with earthy odours may have occurred previously in the must and novel methods are required for this commodity. In the present report, several parameters of the SPME were evaluated to optimize geosmin extraction. The method permitted quantification of geosmin and other fungal volatiles by Gas Chromatography-Mass Spectrometer (GC-MS) at very low concentrations. Limits of detection and quantification (L(D) and L(Q)) for geosmin were 4.7 ng L(-1) and 15.6 ng L(-1) respectively. The RSD was 4.1% and the recovery rates ranged from 115% to 134%. Uniquely, haloanisoles were analyzed by using only one internal standard (2,3,6-trichloroanisole) thus avoiding the synthesis of deuterated anisole analogues that are used as internal standard in other methods. The method was used for the analysis of grape juice samples inoculated with B. cinerea and P. expansum. Geosmin and methylisoborneol were the compounds that appeared to contribute most to earthy odours, although other fungal compounds which are claimed to cause earthy or mouldy off-odours were detected (e.g. 1-octen-3-ol and fenchol).

  19. Time-resolved PIV investigation of flashback in stratified swirl flames of hydrogen-rich fuel

    Science.gov (United States)

    Ranjan, Rakesh; Clemens, Noel

    2016-11-01

    Hydrogen is one of the promising alternative fuels to achieve greener power generation. However, susceptibility of flashback in swirl flames of hydrogen-rich fuels acts as a major barrier to its adoption in gas turbine combustors. The current study seeks to understand the flow-flame interaction during the flashback of the hydrogen-rich flame in stratified conditions. Flashback experiments are conducted with a model combustor equipped with an axial swirler and a center-body. Fuel is injected in the main swirl flow via the fuel ports on the swirler vanes. To achieve mean radial stratification, these fuel ports are located at a radial location closer to the outer wall of the mixing tube. Stratification in the flow is assessed by employing Anisole PLIF imaging. Flashback is triggered by a rapid increase in the global equivalence ratio. The upstream propagation of the flame is investigated by employing time-resolved stereoscopic PIV and chemiluminescence imaging. Stratification leads to substantially different flame propagation behavior as well as increased flame surface wrinkling. We gratefully acknowledge the sponsorship by the DOE NETL under Grant DEFC2611-FE0007107.

  20. Search for Anomalous Single Top Quark Production in Association with a Photon in pp Collisions at $\\sqrt{s}$ = 8 TeV

    CERN Document Server

    Goldouzian, Reza

    2016-01-01

    This thesis reports the results of a first search for the flavor-changing neutral current(FCNC) through the anomalous production of single top quark in association witha photon due to the anomalous interactions of tqγ (q = u or c) in pp collisions. Thissearch is performed using 19.8 fb−1 of data collected with the CMS detector at thecenter-of-mass energy of 8 TeV.In this study we only concentrate on the muonic decay of the W-boson in topquark decay. The search is conducted in final states with an isolated muon, anisolated photon, jets, at most one of which is consistent with originating from theevolution of a b quark, and missing transverse momentum, corresponding to topquark decays, in which the W boson from the top quark decay is detected in the µν.A multivariate classification approach is chosen to achieve a powerful discrimination between signal like events and standard model backgrounds. No evidencefor the FCNC processes are observed. Upper limits at 95% confidence level on thestrengths of the ...

  1. A Lean Methane Prelixed Laminar Flame Doped witg Components of Diesel Fuel. Part I: n)Butylbenzene

    CERN Document Server

    Pousse, Emir; Fournet, René; Battin-Leclerc, Frédérique; 10.1016/j.combustflame.2008.09.012

    2009-01-01

    To better understand the chemistry involved during the combustion of components of diesel fuel, the structure of a laminar lean premixed methane flame doped with n-butylbenzene has been investigated. The inlet gases contained 7.1% (molar) of methane, 36.8% of oxygen and 0.96% of n-butylbenzene corresponding to an equivalence ratio of 0.74 and a ratio C10H14 / CH4 of 13.5%. The flame has been stabilized on a burner at a pressure of 6.7 kPa using argon as diluent, with a gas velocity at the burner of 49.2 cm/s at 333 K. Quantified species included the usual methane C0-C2 combustion products, but also 16 C3-C5 hydrocarbons, 7 C1-C3 oxygenated compounds, as well as 20 aromatic products, namely benzene, toluene, phenylacetylene, styrene, ethylbenzene, xylenes, allylbenzene, propylbenzene, cumene, methylstyrenes, butenylbenzenes, indene, indane, naphthalene, phenol, benzaldehyde, anisole, benzylalcohol, benzofuran, and isomers of C10H10 (1-methylindene, dihydronaphtalene, butadienylbenzene). A new mechanism for the...

  2. Rapid discrimination and characterization of vanilla bean extracts by attenuated total reflection infrared spectroscopy and selected ion flow tube mass spectrometry.

    Science.gov (United States)

    Sharp, Michael D; Kocaoglu-Vurma, Nurdan A; Langford, Vaughan; Rodriguez-Saona, Luis E; Harper, W James

    2012-03-01

    Vanilla beans have been shown to contain over 200 compounds, which can vary in concentration depending on the region where the beans are harvested. Several compounds including vanillin, p-hydroxybenzaldehyde, guaiacol, and anise alcohol have been found to be important for the aroma profile of vanilla. Our objective was to evaluate the performance of selected ion flow tube mass spectrometry (SIFT-MS) and Fourier-transform infrared (FTIR) spectroscopy for rapid discrimination and characterization of vanilla bean extracts. Vanilla extracts were obtained from different countries including Uganda, Indonesia, Papua New Guinea, Madagascar, and India. Multivariate data analysis (soft independent modeling of class analogy, SIMCA) was utilized to determine the clustering patterns between samples. Both methods provided differentiation between samples for all vanilla bean extracts. FTIR differentiated on the basis of functional groups, whereas the SIFT-MS method provided more specific information about the chemical basis of the differentiation. SIMCA's discriminating power showed that the most important compounds responsible for the differentiation between samples by SIFT-MS were vanillin, anise alcohol, 4-methylguaiacol, p-hydroxybenzaldehyde/trimethylpyrazine, p-cresol/anisole, guaiacol, isovaleric acid, and acetic acid. ATR-IR spectroscopy analysis showed that the classification of samples was related to major bands at 1523, 1573, 1516, 1292, 1774, 1670, 1608, and 1431 cm(-1) , associated with vanillin and vanillin derivatives.

  3. Stereoelectronic effects on 1H nuclear magnetic resonance chemical shifts in methoxybenzenes

    DEFF Research Database (Denmark)

    Lambert, Maja; Olsen, Lars; Jaroszewski, Jerzy W

    2006-01-01

    the Ar-OCH3 torsion out of the ring plane, resulting in large stereoelectronic effects on the chemical shift of Hpara. Conformational searches and geometry optimizations for 3-16 at the B3LYP/6-31G** level, followed by B3LYP/6-311++G(2d,2p) calculations for all low-energy conformers, gave excellent......Investigation of all O-methyl ethers of 1,2,3-benzenetriol and 4-methyl-1,2,3-benzenetriol (3-16) by 1H NMR spectroscopy and density-functional calculations disclosed practically useful conformational effects on 1H NMR chemical shifts in the aromatic ring. While the conversion of phenol (2......) to anisole (1) causes only small positive changes of 1H NMR chemical shifts (Delta delta Hmeta > Hpara, the experimental O-methylation induced shifts in ortho-disubstituted phenols are largest for Hpara, Delta delta equals; 0.19 +/- 0.02 ppm (n = 11...

  4. A Multifunctional and Possible Skin UV Protectant, (3R-5-Hydroxymellein, Produced by an Endolichenic Fungus Isolated from Parmotrema austrosinense

    Directory of Open Access Journals (Sweden)

    Lu Zhao

    2016-12-01

    Full Text Available Lichens are considered a great bio-resource because they produce large numbers of secondary metabolites with many biological activities; however, they have not been cultivated under artificial conditions to date. As a result, lichen substances from natural sources are limited and have not been widely utilized in commercial applications. Accordingly, interest in lichen-associated fungi, especially endogenic fungi, has increased. Ultraviolet (UV radiation in sunlight is harmful to human health, resulting in demand for effective UV filtering agents for use in sunscreen. In this study, we purified (3R-5-hydroxymellein, which has UVA absorption activity, from the secondary metabolites of an endolichenic fungus (ELF000039. The antioxidant properties were then assessed by in vitro tests. The antioxidant activity of (3R-5-hydroxymellein was high when compared to the recognized antioxidants ascorbic acid (ASA and butyl hydroxyl anisole (BHA. Moreover, the compound exhibited no cytotoxicity toward mouse melanoma cell lines, B16F1 and B16F10, or the normal cell line, HaCaT. Furthermore, (3R-5-hydroxymellein recovered the damage caused by UVB irradiation and inhibited melanin synthesis. Taken together, these results suggest that (3R-5-hydroxymellein could have an interesting and vital profile to go further development as a multifunctional skin UV protectant.

  5. Fabrication of a Liquid Crystal Capacitor Cell using Spin-Coating

    Science.gov (United States)

    Tate, Logan; Ducharme, Tabatha; Prayaga, Chandra; Wade, Aaron; Huggins, Michael; Chandler, Rebecca; Renaud, Amy

    2013-03-01

    This paper presents our work to fabricate and characterize a liquid crystal capacitor cell using novel liquid crystals. These LCs are not in their isotropic phase at room temperature and require the capacitor cells to be fabricated around them. This was done using spin coating where the samples were dissolved in Toluene, Anisole, or C4CL. Next, the liquid crystals were spin-coated on either an ITO coated glass slide or a separate silicon wafer. This spin coating process was done in two stages where the first stage started at a slow speed to begin spreading the sample, and then during the second stage the spin coater ramped to a higher rpm to thin the sample while removing excess material. M-Line spectroscopy was used to determine the films thickness of the silicon substrate sample. To make the capacitor cell, a second ITO coated slide was placed on top of the first and the edges sealed with epoxy. Wires were soldered to the bus bars and the samples were mounted in a temperature controlled environment constructed in the lab and an RC circuit was assembled using the LC capacitor. Initial dielectric measurements were taken at room temperature to ensure the integrity of the cell.

  6. Non-target screening of extractable and non-extractable organic xenobiotics in riverine sediments of Ems and Mulde Rivers, Germany

    Energy Technology Data Exchange (ETDEWEB)

    Kronimus, Alexander [Institute of Geology and Geochemistry of Petroleum and Coal, RWTH Aachen University, Lochnerstr. 4-20, D-52056 Aachen (Germany)]. E-mail: kronimus@lek.rwth-aachen.de; Schwarzbauer, Jan [Institute of Geology and Geochemistry of Petroleum and Coal, RWTH Aachen University, Lochnerstr. 4-20, D-52056 Aachen (Germany)]. E-mail: schwarzbauer@lek.rwth-aachen.de

    2007-05-15

    Subaquatic sediment samples derived form Elbe and Mulde Rivers, Germany, were analyzed for extractable and non-extractable anthropogenic organic compounds by a non-target screening approach. Applied methodologies were gas chromatography-mass spectrometry, dispersion extraction and degradation procedures, particularly alkaline and acidic hydrolysis, boron tribromide treatment, ruthenium tetroxide oxidation as well as pyrolysis and TMAH (tetramethylammonium hydroxide)-thermochemolysis. Numerous compounds were identified, including halogenated benzenes, anisoles, styrenes, alkanes, diphenylmethane derivates, anilines, phenols and diphenyl ethers. The results were interpreted with respect to compound specific modes of incorporation as well as to potential sources (e.g. municipal, agricultural, industrial). Extractable and non-extractable fractions differed significantly with respect to their qualitative and quantitative composition. For example, quantities in the extractable and non-extractable fractions of chlorinated benzenes differed up to factor 50. Among other significant results, the investigation revealed hints for a dependence of the mode of incorporation of chlorinated benzenes on their substitution pattern. - Analysis of both, extractable and non-extractable fraction of organic xenobiotics in sediments reveals a more detailed and comprehensive anthropogenic load profile.

  7. Activation of Peroxymonosulfate by Subsurface Minerals

    Science.gov (United States)

    Yu, Miao; Teel, Amy L.; Watts, Richard J.

    2016-08-01

    In situ chemical oxidation (ISCO) has become a widely used technology for the remediation of soil and groundwater. Although peroxymonosulfate is not a common oxidant source for ISCO, its chemical structure is similar to the ISCO reagents hydrogen peroxide and persulfate, suggesting that peroxymonosulfate may have the beneficial properties of each of these oxidants. Peroxymonosulfate activation in the presence of subsurface minerals was examined as a basis for ISCO, and possible reactive species (hydroxyl radical, sulfate radical, and reductants + nucleophiles) generated in the mineral-activated peroxymonosulfate systems were investigated. Rates of peroxymonosulfate decomposition and generation rates of reactive species were studied in the presence of three iron oxides, one manganese oxide, and three soil fractions. The iron oxide hematite-activated peroxymonosulfate system most effectively degraded the hydroxyl radical probe nitrobenzene. Reductants + nucleophiles were not generated in mineral-activated peroxymonosulfate systems. Use of the probe compound anisole in conjunction with scavengers demonstrated that both sulfate radical and hydroxyl radical are generated in mineral-activated peroxymonosulfate systems. In order to confirm the activation of peroxymonosulfate by subsurface minerals, one natural soil and associated two soil fractions were evaluated as peroxymonosulfate catalysts. The natural soil did not effectively promote the generation of oxidants; however, the soil organic matter was found to promote the generation of reductants + nucleophiles. The results of this research show that peroxymonosulfate has potential as an oxidant source for ISCO applications, and would be most effective in treating halogenated contaminants when soil organic matter is present in the subsurface.

  8. Which hydrogen atom of toluene protonates PAH molecules in (+)-mode APPI MS analysis?

    Science.gov (United States)

    Ahmed, Arif; Ghosh, Manik Kumer; Choi, Myung Chul; Choi, Cheol Ho; Kim, Sunghwan

    2013-03-01

    A previous study (Ahmed, A. et al., Anal. Chem. 84, 1146-1151( 2012) reported that toluene used as a solvent was the proton source for polyaromatic hydrocarbon compounds (PAHs) that were subjected to (+)-mode atmospheric-pressure photoionization. In the current study, the exact position of the hydrogen atom in the toluene molecule (either a methyl hydrogen or an aromatic ring hydrogen) involved in the formation of protonated PAH ions was investigated. Experimental analyses of benzene and anisole demonstrated that although the aromatic hydrogen atom of toluene did not contribute to the formation of protonated anthracene, it did contribute to the formation of protonated acridine. Thermochemical data and quantum mechanical calculations showed that the protonation of anthracene by an aromatic ring hydrogen atom of toluene is endothermic, while protonation by a methyl hydrogen atom is exothermic. However, protonation of acridine by either an aromatic ring hydrogen or a methyl hydrogen atom of toluene is exothermic. The different behavior of acridine and anthracene was attributed to differences in gas-phase basicity. It was concluded that both types of hydrogen in toluene can be used for protonation of PAH compounds, but a methyl hydrogen atom is preferred, especially for non-basic compounds.

  9. New URJC-1 Material with Remarkable Stability and Acid-Base Catalytic Properties

    Directory of Open Access Journals (Sweden)

    Pedro Leo

    2016-02-01

    Full Text Available Emerging new metal-organic structures with tunable physicochemical properties is an exciting research field for diverse applications. In this work, a novel metal-organic framework Cu(HIT(DMF0.5, named URJC-1, with a three-dimensional non-interpenetrated utp topological network, has been synthesized. This material exhibits a microporous structure with unsaturated copper centers and imidazole–tetrazole linkages that provide accessible Lewis acid/base sites. These features make URJC-1 an exceptional candidate for catalytic application in acid and base reactions of interest in fine chemistry. The URJC-1 material also displays a noteworthy thermal and chemical stability in different organic solvents of different polarity and boiling water. Its catalytic activity was evaluated in acid-catalyzed Friedel–Crafts acylation of anisole with acetyl chloride and base-catalyzed Knoevenagel condensation of benzaldehyde with malononitrile. In both cases, URJC-1 material showed very good performance, better than other metal organic frameworks and conventional catalysts. In addition, a remarkable structural stability was proven after several consecutive reaction cycles.

  10. New Linear Partitioning Models based on Experimental Water – Supercritical CO2 Partitioning Data of Selected Organic Compounds

    Energy Technology Data Exchange (ETDEWEB)

    Burant, Aniela S.; Thompson, Christopher J.; Lowry, Gregory; Karamalidis, Athanasios

    2016-05-17

    Partitioning coefficients of organic compounds between water and supercritical CO2 (sc-CO2) are necessary to assess the risk of migration of these chemicals from subsurface CO2 storage sites. Despite the large number of potential organic contaminants, the current data set of published water-sc-CO2 partitioning coefficients is very limited. Here, the partitioning coefficients of thiophene, pyrrole, and anisole were measured in situ over a range of temperatures and pressures using a novel pressurized batch reactor system with dual spectroscopic detectors: a near infrared spectrometer for measuring the organic analyte in the CO2 phase, and a UV detector for quantifying the analyte in the aqueous phase. Our measured partitioning coefficients followed expected trends based on volatility and aqueous solubility. The partitioning coefficients and literature data were then used to update a published poly-parameter linear free energy relationship and to develop five new linear free energy relationships for predicting water-sc-CO2 partitioning coefficients. Four of the models targeted a single class of organic compounds. Unlike models that utilize Abraham solvation parameters, the new relationships use vapor pressure and aqueous solubility of the organic compound at 25 °C and CO2 density to predict partitioning coefficients over a range of temperature and pressure conditions. The compound class models provide better estimates of partitioning behavior for compounds in that class than the model built for the entire dataset.

  11. Investigation of the behaviour of solid acid catalysts for acylations and cyanisations of aromatics. Final report; Untersuchungen zur Wirkungsweise von festen sauren Katalysatoren bei Acylierungen und Cyanierungen von Aromaten. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Kemnitz, E.

    2002-01-01

    The present state of the art in the field of FRIEDEL-CRAFTS-ACYLATIONS is characterized by the application of homogenous catalysts (at least stochiometric amounts) like AlCl{sub 3} or FeCl{sub 3}. Problems arising from this application are corrosions, difficult product separations from the catalyst and the origin of acid waste water. Hence, the aim of this project was the development of suitable solid catalysts which overcome the problems ascribed above. Sulfated zirconia (SZ) was found to be an excellent solid Br.o/nsted-acid to be used especially in their aerogel or cryogel form. Thus with this catalyst system, in the benzoylation of anisol nearly 100% conversion may be achieved. In this way it could be proved, that with SZ a solid Br.o/nsted-acid might be available which gives reasonable hope to substitute in a near future, at least for some reactions, the classical homogeneous catalysts and to overcome their problems in use. (orig.)

  12. Solid-phase synthesis of huwentoxin-I and its structure and bioactivity analysis

    Institute of Scientific and Technical Information of China (English)

    梁宋平; 夏赞贤; 谢锦云

    1997-01-01

    Huwentoxin-I, a neurotoxic peptide from the spider Selenocosmia huwena, was synthesized by sol-id-phase method with Fluorenylmethoxycarbonyl amino acid pentafluorophenyl esters (Fmoc-AA-OPfp). The carboxyl and the hydroxy groups were protected by tBu; the side chains of Lys and His were protected by Roc; the guanidine group of Arg was protected by Mtr and the mercaptan group of Cys was protected by Trt. The solid-phase carrier was ethylene diamine-polyethylene-polystyrene (DEA-PEG-PS) resin. The synthetic peptide was cleaved from the resin and deprotected by a 90% TFA solution containing 5% thioanisole, 3% ethanedithiol and 2% anisole. The product was reduced with DTT and then incubated with GSSG and GSH to form the correct disulfide bond linkages. The syn-thetic peptide was purified by HPLC and then characterized by amino acid composition and sequence analysis, peptide mapping and NMR. The biological activity of the synthetic product was tested by electrophysiological method using the isolated mouse ph

  13. The environmental behaviour of polychlorinated phenols and its relevance to cork forest ecosystems: a review.

    Science.gov (United States)

    McLellan, Iain; Carvalho, Mariana; Silva Pereira, Cristina; Hursthouse, Andrew; Morrison, Calum; Tatner, Paul; Martins, Isabel; San Romão, M Vitória; Leitão, Maria

    2007-10-01

    Pentachlorophenol (PCP) has been used as a herbicide, biocide and preservative worldwide since the 1930s and as a result, extensive and prolonged contamination exists. The environmental impact increases when its many degradation products are taken into consideration. A number of chloroanisols and their related chlorophenols have been found in cork slabs collected from Portuguese oak tree forests before stopper manufacturing, and contamination by PCP and polychlorinated anisole (PCA) has been detected in Canadian forests. It is suggested that the use of polychlorinated phenols, in particular PCP, is thought to be a cause of the cork taint problem in wine, a major socio-economic impact not only for industry but on sensitive and highly biodiverse ecosystems. It also highlights particular issues relating to the regional regulation of potentially toxic chemicals and global economics world wide. To fully understand the impact of contamination sources, the mechanisms responsible for the fate and transport of PCP and its degradation products and assessment of their environmental behaviour is required. This review looks at the current state of knowledge of soil sorption, fate and bioavailability and identifies the challenges of degradation product identification and the contradictory evidence from field and laboratory observations. The need for a systematic evaluation of PCP contamination in relation to cork forest ecosystems and transfer of PCP between trophic levels is emphasised by discrepancies in bioaccumulation and toxicity. This is essential to enable long term management of not only transboundary contaminants, but also the sustainable management of socially and economically important forest ecosystems.

  14. Synthesis, antioxidant and antimicrobial activity of novel vanillin derived piperidin-4-one oxime esters: preponderant role of the phenyl ester substituents on the piperidin-4-one oxime core.

    Science.gov (United States)

    Harini, Salakatte Thammaiah; Kumar, Honnaiah Vijay; Rangaswamy, Javarappa; Naik, Nagaraja

    2012-12-15

    The study has been achieved the efficient synthesis of vanillin derived piperidin-4-one oxime esters (5a-m) via four step reaction involved Mannich reaction of vanillin, acetone and ammonium acetate to obtain 2,6-bis(4-hydroxy-3-methoxyphenyl)-piperidin-4-one 2 followed by N-methylation and oximation. Further, to enhance the biological activity of vanillin derived piperidin-4-one oxime core, esterification of 4 with substituted benzoyl chlorides in the presence of strong organic base t-BuOK accomplished a series of vanillin derived piperidin-4-one oxime esters (5a-m). The synthesized analogues are screened for their antioxidant and antimicrobial studies and the preponderant effect of the phenyl ester substituents on the biological activity of piperidin-4-one oxime core was demonstrated. Among the tested compounds, 5i and 5j are emerged as outperformed antioxidants than standard Butylated hydroxy anisole (BHA) whereas, compounds 5b and 5d manifested potent antibacterial and antifungal activity than standard streptomycin and fluconazole respectively.

  15. "High in omega-3 fatty acids" bologna-type sausages stabilized with an aqueous-ethanol extract of Melissa officinalis.

    Science.gov (United States)

    Berasategi, Izaskun; Legarra, Sheila; de Ciriano, Mikel García-Íñiguez; Rehecho, Sheyla; Calvo, Maria Isabel; Cavero, Rita Yolanda; Navarro-Blasco, Iñigo; Ansorena, Diana; Astiasarán, Iciar

    2011-08-01

    A new formulation of bologna-type sausage enriched in ω-3 polyunsaturated fatty acids (PUFA) (8.75% linseed oil) was developed, using a lyophilized aqueous-ethanolic extract of Melissa officinalis. A comparison with the effectiveness of butylhydroxy anisole (BHA) synthetic antioxidant to decrease the oxidation of PUFAs was performed. The formulation increased the ω-3 PUFAs content, especially α-linolenic acid, decreasing significantly the ω-6/ω-3 ratio from 17.3 to 1.9, and also the Atherogenic Index and Thrombogenic Index (0.38-0.31 and 1.03-0.54, respectively). Modified sausages with BHA and Melissa extract showed significantly lower peroxides value (2.62 and 6.11 meq O₂/kg) and thiobarbituric acid value (0.26 and 0.27 mg malondialdehyde/kg) and higher antioxidant capacity (hydrophilic fraction ABTS: 0.45 and 0.74 meq Trolox/g product; lipofilic fraction ABTS: 0.44 and 0.37 meq Trolox/g product) than those without these ingredients (16.49 meq O₂/kg, 2.08 mg malondialdehyde /kg, 0.26 and 0.27 meq Trolox/g product, respectively). Sensorial tests showed that acceptability of the new formulations was similar to control products.

  16. Catalytic Hydrodeoxygenation of Bio-oil Model Compounds over Pt/HY Catalyst

    Science.gov (United States)

    Lee, Heejin; Kim, Hannah; Yu, Mi Jin; Ko, Chang Hyun; Jeon, Jong-Ki; Jae, Jungho; Park, Sung Hoon; Jung, Sang-Chul; Park, Young-Kwon

    2016-06-01

    The hydrodeoxygenation of a model compound of lignin-derived bio-oil, guaiacol, which can be obtained from the pyrolysis of biomass to bio-oil, has attracted considerable research attention because of its huge potential as a substitute for conventional fuels. In this study, platinum-loaded HY zeolites (Pt/HY) with different Si/Al molar ratios were used as catalysts for the hydrodeoxygenation of guaiacol, anisole, veratrole, and phenol to a range of hydrocarbons, such as cyclohexane. The cyclohexane (major product) yield increased with increasing number of acid sites. To produce bio-oil with the maximum level of cyclohexane and alkylated cyclohexanes, which would be suitable as a substitute for conventional transportation fuels, the Si/Al molar ratio should be optimized to balance the Pt particle-induced hydrogenation with acid site-induced methyl group transfer. The fuel properties of real bio-oil derived from the fast pyrolysis of cork oak was improved using the Pt/HY catalyst.

  17. Effects of the origins of Botrytis cinerea on earthy aromas from grape broth media further inoculated with Penicillium expansum.

    Science.gov (United States)

    Morales-Valle, H; Silva, L C; Paterson, R R M; Venâncio, A; Lima, N

    2011-08-01

    Earthy "off" aromas from wine and grape juice are highly detrimental to the production of quality grape products. These volatile compounds are produced on grapes by Botrytis cinerea, Penicillium expansum and/or a combination of P. expansum and B. cinerea strains. B. cinerea strains were isolated from different (a) vineyards in Spain and Portugal, (b) grape varieties (c) bunches (i.e., sound and botrytized) and (d) positions in the botrytized bunch (i.e., interior or exterior). A novel Headspace-Phase Microextraction (SPME) followed by Gas Chromatrography/Mass Spectrometry (GC-MS) dedicated to analyze geosmin, methylisoborneol (MIB), 1-octen-3-ol, fenchone and fenchol in grape broth medium was used. Approximately 50% of the B. cinerea strains induced detectable geosmin. One strain accumulated significant amounts of anisoles, demonstrating that this contamination might already occur in the vineyard. Strains from the interior of Cainho grape bunches induced more geosmin and hence it may be possible to reduce this volatile in wine by avoiding using these grapes in case of B. cinerea attack.

  18. 营养型调和油配方及甘草、诃子提取物复合抗氧化剂对其抗氧化作用的研究%Study on the formulation of nutrition-based blend oil and the antioxidant activity of compound antioxidants from Glycyrrhiza uralensis extract and Terminalia chebula extract on it

    Institute of Scientific and Technical Information of China (English)

    刘艳凤; 刘雅丽; Chogsom Munkh-Amgalan; 陈贵林

    2015-01-01

    Objective To ensure the formulation of nutrition-based blend oil and research the effect of antioxidants on the compound antioxidants of Glycyrrhiza uralensis Fisch. extract (GUE) and Terminalia chebula Retz. extract (TCE) on the nutrition-based blend oil. Methods According to the mathematical model for the preparation of nutrition-based blend oil, the oil content of all kinds of fatty acids in raw materials was determined by gas chromatography-mass spectrometry (GC-MS). Due to Schaal experiment the antioxidant capacity of compound antioxidants was evaluated. Results The optimal ratio to match the comparison of peanut oil, sunflower oil and flaxseed oil was 68.68:19.23:12.08. Synergistic effects were observed in the order:0.003%GUE+0.017%Vc>0.005%TCE+0.015%Vc>0.017%TCE+0.003%Ve>0.017%GUE+0.003%Ve by Schaal oven method, and especially for combinations of 0.003%GUE and 0.017%Vc, which showed a greater synergistic effect than that of the each individual antioxidant and some synthetic antioxidants, such as Butyl hydroxyl anisole (BHA). There was no significant difference between it and 2,6-Di-tert-butyl-p-cresol (BHT). Conclusion Compound antioxidants of GUE and TCE can offer effective alternative to synthetic antioxidants during storage of vegetable oils.%目的:研究甘草提取物(Glycyrrhiza uralensis extract, GUE)、诃子提取物(Terminalia chebula extract, TCE)复合抗氧化剂对营养型调和油氧化程度的影响。方法采用气质联用(gas chromatography-mass spectrometer, GC-MS)方法测定原料油中各类脂肪酸的含量,根据数学模型制备营养型调和油;然后采用 Schaal 烘箱法,评价复合抗氧化剂对营养型调和油的抗氧化作用,筛选出抗氧化作用较强的复合抗氧化剂。结果调和油的最佳配比花生油68.68%、葵花籽油19.23%、亚麻籽油12.08%。复合抗氧化剂对调和油的抗氧化作用顺序为:0.003%GUE+0.017%Vc>0.005%TCE+0.015%Vc>0.017%TCE+0.003%Ve>0.017%GUE+0.003%Ve,0

  19. 苯酚与碳酸二甲酯烷基化反应体系的热力学分析%THERMODYNAMICS ANALYSIS FOR THE REACTION SYSTEM OF THE ALKYLATION OF PHENOL WITH DIMETHYL CARBONATE

    Institute of Scientific and Technical Information of China (English)

    胡海生; 薛冰; 许杰; 徐崇福; 李永昕

    2012-01-01

    By using the Benson group contribution method, the related thermodynamics data of anisole are calculated. For alkylation of phenol with dimethyl carbonate (DMC) to produce anisole and cre-sols, the enthalpy change Ar Hm , free energy change ArGm and equilibrium constant Ka of each reaction at 300 - 1 000 K and 5-30 Mpa are also calculated and then discussed according to the principles of chemical thermodynamics. The results show that the alkylation of phenol with DMC is thermodynami-cally feasible, and the equilibrium constant of Oalkylation is much higher than that of Oalkylation. Among the three C-alkylation reactions? The equilibrium constant of the reaction producing m-cresol is the highest and that of the reaction producing />-cresol is the lowest. With the increase in pressure, a slight increase in the free energy is observed, which indicates that higher pressure is not in favor of the alkylation of phenol with DMC. Under the same pressure, the equilibrium constants of C-alkylation are much higher than that of Oalkylation. The results provide a set of basic thermodynamic data for studying alkylation of phenol with DMC and developing catalysts for the reaction.%采用Benson基团贡献法,计算了苯甲醚(MPE)的相关热力学数据.在300~1 000 K和5~30MPa范围内,计算了苯酚与碳酸二甲酯烷基化反应生成甲基苯酚异构体和苯甲醚各反应的焓变△rHm、吉布斯自由能变△rGm和平衡常数Kθ.结果表明:苯酚与DMC的烷基化反应是可以自发进行的,且碳烷基化反应平衡常数远高于氧烷基化反应平衡常数,在3个碳上烷基化反应中,生成间甲酚的平衡常数最大,生成对甲酚的平衡常数最小;随着压力的升高,各反应的自由能均略有增加,表明升高压力不利于烷基化反应的进行,在同一压力下,碳烷基化反应的平衡常数远高于氧烷基化反应,为苯酚与碳酸二甲酯烷基化反应条件的控制和催化剂的探索研究提供了热力学依据.

  20. Synthesis of tin and tin oxide nanoparticles of low size dispersity for application in gas sensing.

    Science.gov (United States)

    Nayral, C; Viala, E; Fau, P; Senocq, F; Jumas, J C; Maisonnat, A; Chaudret, B

    2000-11-17

    Nanocomposite core-shell particles that consist of a Sn0 core surrounded by a thin layer of tin oxides have been prepared by thermolysis of [(Sn(NMe2)2)2] in anisole that contains small, controlled amounts of water. The particles were characterized by means of electronic microscopies (TEM, HRTEM, SEM), X-ray diffraction (XRD) studies, photoelectron spectroscopy (XPS), and Mossbauer spectroscopy. The TEM micrographs show spherical nanoparticles, the size and size distribution of which depends on the initial experimental conditions of temperature, time, water concentration, and tin precursor concentration. Nanoparticles of 19 nm median size and displaying a narrow size distribution have been obtained with excellent yield in the optimized conditions. HRTEM, XPS, XRD and Mossbauer studies indicate the composite nature of the particles that consist of a well-crystallized tin beta core of approximately equals 11 nm covered with a layer of approximately equals 4 nm of amorphous tin dioxide and which also contain quadratic tin monoxide crystallites. The thermal oxidation of this nanocomposite yields well-crystallized nanoparticles of SnO2* without coalescence or size change. XRD patterns show that the powder consists of a mixture of two phases: the tetragonal cassiterite phase, which is the most abundant, and an orthorhombic phase. In agreement with the small SnO2 particle size, the relative intensity of the adsorbed dioxygen peak observed on the XPS spectrum is remarkable, when compared with that observed in the case of larger SnO2 particles. This is consistent with electrical conductivity measurements, which demonstrate that this material is highly sensitive to the presence of a reducing gas such as carbon monoxide.

  1. Enthalpy of Formation and O-H Bond Dissociation Enthalpy of Phenol: Inconsistency between Theory and Experiment.

    Science.gov (United States)

    Dorofeeva, Olga V; Ryzhova, Oxana N

    2016-04-21

    Gas-phase O–H homolytic bond dissociation enthalpy in phenol, DH298°(C6H5O–H), is still disputed, despite a large number of experimental and computational studies. In estimating this value, the experimental enthalpy of formation of phenol, ΔfH298°(C6H5OH, g) = −96.4 ± 0.6 kJ/mol (Cox, J. D. Pure Appl. Chem. 1961, 2, 125−128), is often used assuming high accuracy of the experimental value. In the present work a substantially less negative value of ΔfH298°(C6H5OH, g) = −91.8 ± 2.5 kJ/mol was calculated combining G4 theory with an isodesmic reaction approach. A benchmark quality of this result was achieved by using a large number of reliable reference species in isodesmic reaction calculations. Among these are the most accurate ΔfH298° values currently available from the Active Thermochemical Tables (ATcT) for 36 species (neutral molecules, radicals, and ions), anisole with recently reassessed enthalpy of formation, and 13 substituted phenols. The internal consistency of the calculated ΔfH298°(C6H5OH, g) value with the experimental enthalpies of formation of more than 50 reference species suggests that the reported experimental enthalpy of formation of phenol is in error. Taking into account that the enthalpy of formation of phenol has not been investigated experimentally since 1961, the new measurements would be extremely valuable. Using the accurate enthalpies of formation of C6H5OH and C6H5O• calculated in the present work, we obtained DH298°(C6H5O–H) = 369.6 ± 4.0 kJ/mol. This value is in satisfactory agreement with that determined from the most precise experimental measurement.

  2. Knock Resistance and Fine Particle Emissions for Several Biomass-Derived Oxygenates in a Direct-Injection Spark-Ignition Engine

    Energy Technology Data Exchange (ETDEWEB)

    Ratcliff, Matthew A.; Burton, Jonathan; Sindler, Petr; Christensen, Earl; Fouts, Lisa; Chupka, Gina M.; McCormick, Robert L.

    2016-04-01

    Several high octane number oxygenates that could be derived from biomass were blended with gasoline and examined for performance properties and their impact on knock resistance and fine particle emissions in a single cylinder direct-injection spark-ignition engine. The oxygenates included ethanol, isobutanol, anisole, 4-methylanisole, 2-phenylethanol, 2,5-dimethyl furan, and 2,4-xylenol. These were blended into a summertime blendstock for oxygenate blending at levels ranging from 10 to 50 percent by volume. The base gasoline, its blends with p-xylene and p-cymene, and high-octane racing gasoline were tested as controls. Relevant gasoline properties including research octane number (RON), motor octane number, distillation curve, and vapor pressure were measured. Detailed hydrocarbon analysis was used to estimate heat of vaporization and particulate matter index (PMI). Experiments were conducted to measure knock-limited spark advance and particulate matter (PM) emissions. The results show a range of knock resistances that correlate well with RON. Molecules with relatively low boiling point and high vapor pressure had little effect on PM emissions. In contrast, the aromatic oxygenates caused significant increases in PM emissions (factors of 2 to 5) relative to the base gasoline. Thus, any effect of their oxygen atom on increasing local air-fuel ratio was outweighed by their low vapor pressure and high double-bond equivalent values. For most fuels and oxygenate blend components, PMI was a good predictor of PM emissions. However, the high boiling point, low vapor pressure oxygenates 2-phenylethanol and 2,4-xylenol produced lower PM emissions than predicted by PMI. This was likely because they did not fully evaporate and combust, and instead were swept into the lube oil.

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

    Energy Technology Data Exchange (ETDEWEB)

    McGregor, D.B.; Brown, A.; Cattanach, P.; Edwards, I.; McBride, D.; Riach, C.; Caspary, W.J.

    1988-01-01

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

  4. [Simultaneous determination of eight additives in polymer food packaging materials by ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry].

    Science.gov (United States)

    Zhang, Xulong; Liu, Yin; Gong, Zhiguo; Wang, Pengju; Wang, Jide; Feng, Shun

    2014-08-01

    An ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was proposed for the simultaneous determination of eight additives (Irgafos 168 (tri(2.4-di-tert-butylphenyl)phosphite), Irganox 1076 (octadecyl-β-(4-hydroxy-3, 5-di-tert-butylphenyl)propionate), Irganox 1010 (pentaerythritol tetrakys 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate), BHA (butyl hydroxy anisole), TBHQ (tertiary butylhydroquinone), PG (propyl gallate), DG (dodecyl gallate), UV-326 (2-( 2'-hydroxyl-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole) in food packaging materials. After extracted by chloromethane through ultrasonic extraction, the samples were analyzed by UPLC-MS/MS. The chromatographic conditions were optimized, and the best separation was obtained on a Waters BEH-C18 column (50 mm x 2. 1 mm, 1.7 μm) with gradient elution of 0. 05% acetic acid solu- tion and methanol. The analysis was performed by UPLC-MS/MS with electrospray ionization (ESI) source in switching between the positive and negative ion modes in one run for multiple reaction monitoring. The eight additives showed good linear relationships in the ranges with all the correlation coefficients (R2) more than 0. 993. The limits of detection (LODs, S/N= 3) and limits of quantitation (LOQs, S/N= 10) of this method were 0. 13-5.50 μg/L and 0.45-17.50 μg/L, respectively. The recoveries were in the range of 63. 9% - 127. 0% with all the RSDs food packaging materials.

  5. DFT evidence for a stepwise mechanism in the O-neophyl rearrangement of 1,1-diarylalkoxyl radicals.

    Science.gov (United States)

    Bietti, Massimo; Ercolani, Gianfranco; Salamone, Michela

    2007-06-08

    Hybrid DFT calculations of the potential energy surface (PES) relative to the O-neophyl rearrangement of a series of ring-substituted 1,1-diarylalkoxyl radicals have been carried out at the UB3LYP/6-31G(d) level of theory. On the basis of the computational data, the rearrangement can be described as a consecutive reaction of the type a b --> c (see above graphic), and the steady-state approximation could be applied in all cases to the intermediate b. The first-order rearrangement rate constants [kobs = k1k2/(k-1 + k2)] were thus obtained from the computed activation free-energies and were compared with the experimental rate constants measured previously in MeCN solution by laser flash photolysis. An excellent agreement is observed along the two series, which strongly supports the hypothesis that the O-neophyl rearrangement of 1,1-diarylalkoxyl radicals proceeds through the formation of the reactive 1-oxaspiro [2,5]octadienyl radical intermediate. This is in contrast to previous hypotheses that involve either a long-lived intermediate or the absence of this intermediate along the reaction path. The calculated rearrangement free-energies decrease upon going from the methoxy-substituted radical (Delta G degrees = -16.4 kcal x mol-1) to the nitro-substituted one (Delta G degrees = -21.8 kcal x mol-1), which follows a trend that is similar to the one observed for the CAr-O bond dissociation enthalpies (BDEs) of ring-substituted anisoles. This evidence indicates that in the O-neophyl rearrangement the effect of ring substituents on the strength of the newly formed CAr-O bond plays an important role.

  6. EFFECT OF MORINGA OLEIFERA MARINADE ON PROXIMATE COMPOSITION AND SENSORY CHARACTERISTICS OF SMOKE-DRIED AFRICAN CATFISH (CLARIAS GARIEPINUS

    Directory of Open Access Journals (Sweden)

    Kazeem Dauda Adeyemi

    2013-04-01

    Full Text Available The study assessed the effect of Moringa oleifera marinade on chemical composition and organoleptic properties of smoke-dried catfish in a 6x8 factorial experiment. The experimental treatments are the control, 1, 2 and 3% (w/v Moringa oleifera Marinade (MOM, 5% brine and 0.2% Butylated Hydroxyl Anisole (BHA (w/v solutions. Ninety fishes of average weight of 230±8 g were gutted, washed and randomly assigned to the treatments. Thereafter, the fishes were soaked in the treatments for 2 hours and later hot smoked for 12 hours. After smoking, the fishes were stored in air-free netted boxes and placed on laboratory shelves at room temperature (37±20C for 8 weeks. Samples were taken every seven days for chemical and sensory analysis. The proximate analysis showed that Moringa oleifera marinade (MOM reduced the moisture content of smoke-dried fish samples throughout the storage period. The dehydrating property of MOM was concentration dependent with 3% MOM samples having the lowest moisture content, which was significantly different from other treatments. There was no significant difference in the dehydrating properties of 1% MOM, 2% MOM and salt treated samples. All levels of MOM enhanced and maintained the protein, ash and fat content of smoke-dried fish samples. Sensory scores showed no significant difference among the treatments in terms of color, flavor, juiciness and overall acceptability of fish samples. Moringa oleifera marinade could be used to maintain the quality attributes of smoke-dried African catfish stored for 2 months.

  7. In vitro antioxidant and antihyperlipidemic activities of Bauhinia variegata Linn

    Directory of Open Access Journals (Sweden)

    Rajani G

    2009-01-01

    Full Text Available Objectives : To evaluate the ethanolic and aqueous extracts of Bauhinia variegata Linn. for in vitro antioxidant and antihyperlipidemic activity. Materials and Methods : Ethanolic and aqueous extracts of the stem bark and root of B. variegata Linn. were prepared and assessed for in vitro antioxidant activity by various methods namely total reducing power, scavenging of various free radicals such as 1,2-diphenyl-2-picrylhydrazyl (DPPH, super oxide, nitric oxide, and hydrogen peroxide. The percentage scavenging of various free radicals were compared with standard antioxidants such as ascorbic acid and butylated hydroxyl anisole (BHA. The extracts were also evaluated for antihyperlipidemic activity in Triton WR-1339 (iso-octyl polyoxyethylene phenol-induced hyperlipidemic albino rats by estimating serum triglyceride, very low density lipids (VLDL, cholesterol, low-density lipids (LDL, and high-density lipid (HDL levels. Result : Significant antioxidant activity was observed in all the methods, (P < 0.01 for reducing power and (P < 0.001 for scavenging DPPH, super oxide, nitric oxide, and hydrogen peroxide radicals. The extracts showed significant reduction (P < 0.01 in cholesterol at 6 and 24 h and (P < 0.05 at 48 h. There was significant reduction (P < 0.01 in triglyceride level at 6, 24, and 48 h. The VLDL level was also significantly (P < 0.05 reduced from 24 h and maximum reduction (P < 0.01 was seen at 48 h. There was significant increase (P < 0.01 in HDL at 6, 24, and 48 h. Conclusion : From the results, it is evident that alcoholic and aqueous extracts of B. variegata Linn. can effectively decrease plasma cholesterol, triglyceride, LDL, and VLDL and increase plasma HDL levels. In addition, the alcoholic and aqueous extracts have shown significant antioxidant activity. By the virtue of its antioxidant activity, B. variegata Linn. may show antihyperlipidemic activity.

  8. The ionization mechanisms in direct and dopant-assisted atmospheric pressure photoionization and atmospheric pressure laser ionization.

    Science.gov (United States)

    Kauppila, Tiina J; Kersten, Hendrik; Benter, Thorsten

    2014-11-01

    A novel, gas-tight API interface for gas chromatography-mass spectrometry was used to study the ionization mechanism in direct and dopant-assisted atmospheric pressure photoionization (APPI) and atmospheric pressure laser ionization (APLI). Eight analytes (ethylbenzene, bromobenzene, naphthalene, anthracene, benzaldehyde, pyridine, quinolone, and acridine) with varying ionization energies (IEs) and proton affinities (PAs), and four common APPI dopants (toluene, acetone, anisole, and chlorobenzene) were chosen. All the studied compounds were ionized by direct APPI, forming mainly molecular ions. Addition of dopants suppressed the signal of the analytes with IEs above the IE of the dopant. For compounds with suitable IEs or Pas, the dopants increased the ionization efficiency as the analytes could be ionized through dopant-mediated gas-phase reactions, such as charge exchange, proton transfer, and other rather unexpected reactions, such as formation of [M + 77](+) in the presence of chlorobenzene. Experiments with deuterated toluene as the dopant verified that in case of proton transfer, the proton originated from the dopant instead of proton-bound solvent clusters, as in conventional open or non-tight APPI sources. In direct APLI using a 266 nm laser, a narrower range of compounds was ionized than in direct APPI, because of exceedingly high IEs or unfavorable two-photon absorption cross-sections. Introduction of dopants in the APLI system changed the ionization mechanism to similar dopant-mediated gas-phase reactions with the dopant as in APPI, which produced mainly ions of the same form as in APPI, and ionized a wider range of analytes than direct APLI.

  9. Ionization of EPA contaminants in direct and dopant-assisted atmospheric pressure photoionization and atmospheric pressure laser ionization.

    Science.gov (United States)

    Kauppila, Tiina J; Kersten, Hendrik; Benter, Thorsten

    2015-06-01

    Seventy-seven EPA priority environmental pollutants were analyzed using gas chromatography-mass spectrometry (GC-MS) equipped with an optimized atmospheric pressure photoionization (APPI) and an atmospheric pressure laser ionization (APLI) interface with and without dopants. The analyzed compounds included e.g., polycyclic aromatic hydrocarbons (PAHs), nitro compounds, halogenated compounds, aromatic compounds with phenolic, acidic, alcohol, and amino groups, phthalate and adipatic esters, and aliphatic ethers. Toluene, anisole, chlorobenzene, and acetone were tested as dopants. The widest range of analytes was ionized using direct APPI (66/77 compounds). The introduction of dopants decreased the amount of compounds ionized in APPI (e.g., 54/77 with toluene), but in many cases the ionization efficiency increased. While in direct APPI the formation of molecular ions via photoionization was the main ionization reaction, dopant-assisted (DA) APPI promoted ionization reactions, such as charge exchange and proton transfer. Direct APLI ionized a much smaller amount of compounds than APPI (41/77 compounds), showing selectivity towards compounds with low ionization energies (IEs) and long-lived resonantly excited intermediate states. DA-APLI, however, was able to ionize a higher amount of compounds (e.g. 51/77 with toluene), as the ionization took place entirely through dopant-assisted ion/molecule reactions similar to those in DA-APPI. Best ionization efficiency in APPI and APLI (both direct and DA) was obtained for PAHs and aromatics with O- and N-functionalities, whereas nitro compounds and aliphatic ethers were the most difficult to ionize. Halogenated aromatics and esters were (mainly) ionized in APPI, but not in APLI.

  10. Characterization of volatiles of necrotic Stenocereus thurberi and Opuntia littoralis and toxicity and olfactory preference of Drosophila melanogster, D. mojavensis wrigleyi, and D. mojavensis sonorensis to necrotic cactus volatiles.

    Science.gov (United States)

    Wright, Cynthia R; Setzer, William N

    2014-08-01

    Drosophila mojavensis wrigleyi and D. mojavensis sonorensis are geographically separated races of cactophilic fruit flies. D. mojavensis sonorensis inhabits the Sonoran Desert and utilizes necrotic rots of Stenocereus thurberi Engelm. as a food source and to oviposit while D. mojavensis wrigleyi inhabits Santa Catalina Island, California and utilizes the necrotic rots of Opuntia littoralis (Engelm.) Cockerell. The objectives of this study were to determine the volatile compositions of the necrotic cacti and to determine if the volatile components show either selective toxicity or attraction toward the fruit flies. The volatile chemical compositions of field-rot specimens of both necrotic cacti were obtained by dynamic headspace (purge-and-trap) and hydrodistillation techniques and analyzed by gas chromatography - mass spectrometry. The volatile fraction of necrotic S. thurberi early rot was dominated by carboxylic acids (84.8%) and the late rot by p-cresol (32.6% in the dynamic headspace sample and 55.9% in the hydrodistilled sample). O. littoralis volatiles were dominated by carboxylic acids (86% in the dynamic headspace sample and 89.1% in the hydrodistilled sample). Fifteen compounds that were identified in the necrotic rot volatiles were used to test insecticidal activity and olfactory preference on the cactophilic Drosophila species, as well as D. melanogaster. Differences in toxicity and olfactory preference were observed between the different taxa. Both races of D. mojavensis exhibited toxicity to benzaldehyde and 2-nonanone, while butanoic acid and palmitic acid were tolerated at high concentrations. D. m. wrigleyi demonstrated a greater olfactory preference for anisole, butanoic acid, 2-heptanone, and palmitic acid than did D. m. sonorensis, while D. m. sonorensis demonstrated a greater preference for hexadecane, octanoic acid, and oleic acid than did D. m. wrigleyi.

  11. Factors inducing human umbilical cord blood-derived mesenchymal stem cells to differentiate into neuron-like cells

    Institute of Scientific and Technical Information of China (English)

    Nawei Zhang; Fengqing Ji

    2006-01-01

    OBJECTIVE:Human umbilical cord blood-derived mesenchymal stem cells (HUCB-derived MSCs)can differentiate into neuron-like cells,which can be used to treat some central nervous system(CNS)diseases.To investigate the factors,which can induce HUCB-derived MSCs to differentiate into neuron-like cells,so as to find effective methods for future clinical application.DATA SOURCES:Using the key terms"human umbilical cord blood"combined with"mesenchymal stem cells,neuron-like cells,neural cells"respectively,the relevant articles in English published during the period from January 1999 to June 2006 were searched from the Medline database.Meanwhile,relevant Chinese articles published from January 1999 to June 2006 were searched Using the same key terms.STUDY SELECTION: All articles associated with the differentiation from human umbilical cord blood into neuron-like cells were selected firstly.Then the full texts were looked up by searchling Ovid medical Journals full-text database and Elsevier Electrical Journals Full-text Database.Articles with full expeiments,enrolled in inducible factors or involved inducible mechanism were retdeved.DATA EXTRACTION:Among 119 collected correlative articles,29 were involved and 90 were excluded.DATA SYNTHESIS:The inducible factors of HUCB-derived MSCs differentiatling into neuron-like cells included renal endothelial growth factors,fibroblasts,β-mercaptoethanol,dimethyl sulfoxide,butyl hydroxyl anisol,brain-derived neurotrophic factor,Danshen,retinoic acid,sodium ferulate and so on,but its mechanism was unclear.CONCLUSION:Human umbilical cord blood-derived MSCs can differentiate into neuron-like cells,with varied inductors.

  12. Retrospective monitoring of triclosan and methyl-triclosan in fish. Results from the German Environmental Specimen Bank

    Energy Technology Data Exchange (ETDEWEB)

    Boehmer, W.; Ruedel, H.; Wenzel, A. [Fraunhofer IME, Schmallenberg (Germany); Schroeter-Kermani, C. [Umweltbundesamt, Berlin (Germany)

    2004-09-15

    During the last years there were several reports on the appearance of the biocides triclosan (TCS; 5- chloro-2-(2,4-dichlorophenoxy)phenol; CAS No. 3380-34-5) and chlorophene (CP; 4-Chloro-2- (phenylmethyl)phenol; CAS No. 120-32-1) in the environment. TCS is used in numerous personal care products like toothpaste and soaps, but also in textiles and shoes. The current annual consumption in Germany is estimated to be 40 t (0.5 g per capita and year). During use large amounts of TCS and CP are disposed into waste water. Modern waste water treatment plants (WWTP) eliminate approximately 95 % of TCS, mainly by biodegradation and adsorption to sludge. It was observed that during waste water treatment methyl-triclosan (MTCS; 5-chloro-2-(2,4-dichlorophenoxy)anisole; CAS No. 4640-01-1) is formed, probably due to microbial methylation. In a WWTP effluent up to 1 % MTCS in relation to TCS was detected. The environmental half-life of TCS is assumed to be low, mainly because it is susceptible to photodegradation at environmental pH levels while MTCS is stable under these conditions. The logPow values of 4.7 for TCS and 5.2 for MTCS (estimated with KowWin Vers. 1,67, respectively) indicate potential for bioaccumulation. Based in order to investigate the exposure of aquatic organisms towards CP, TCS and MTCS in Germany a retrospective monitoring of breams (Abramis brama) from representative rivers was initiated. Samples from the period 1994 to 2003 were taken from the archive of the German Environmental Specimen Bank (ESB) to evaluate temporal changes and regional differences of the occurrence of the target compounds.

  13. Low-cost copper complexes as p-dopants in solution processable hole transport layers

    Energy Technology Data Exchange (ETDEWEB)

    Kellermann, Renate [Department for Materials Science and Engineering, Chair for Materials for Electronics and Energy Technology, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen 91058 (Germany); Siemens AG – Corporate Technology, Guenther-Scharowsky-Str. 1, Erlangen 91058 (Germany); Taroata, Dan; Maltenberger, Anna; Hartmann, David; Schmid, Guenter [Siemens AG – Corporate Technology, Guenther-Scharowsky-Str. 1, Erlangen 91058 (Germany); Brabec, Christoph J. [Department for Materials Science and Engineering, Chair for Materials for Electronics and Energy Technology, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen 91058 (Germany)

    2015-09-07

    We demonstrate the usage of the Lewis-acidic copper(II)hexafluoroacetylacetonate (Cu(hfac){sub 2}) and copper(II)trifluoroacetylacetonate (Cu(tfac){sub 2}) as low-cost p-dopants for conductivity enhancement of solution processable hole transport layers based on small molecules in organic light emitting diodes (OLEDs). The materials were clearly soluble in mixtures of environmentally friendly anisole and xylene and spin-coated under ambient atmosphere. Enhancements of two and four orders of magnitude, reaching 4.0 × 10{sup −11} S/cm with a dopant concentration of only 2 mol% Cu(hfac){sub 2} and 1.5 × 10{sup −9} S/cm with 5 mol% Cu(tfac){sub 2} in 2,2′,7,7′-tetra(N,N-ditolyl)amino-9,9-spiro-bifluorene (spiro-TTB), respectively, were achieved. Red light emitting diodes were fabricated with reduced driving voltages and enhanced current and power efficiencies (8.6 lm/W with Cu(hfac){sub 2} and 5.6 lm/W with Cu(tfac){sub 2}) compared to the OLED with undoped spiro-TTB (3.9 lm/W). The OLED with Cu(hfac){sub 2} doped spiro-TTB showed an over 8 times improved LT{sub 50} lifetime of 70 h at a starting luminance of 5000 cd/m{sup 2}. The LT{sub 50} lifetime of the reference OLED with PEDOT:PSS was only 8 h. Both non-optimized OLEDs were operated at similar driving voltage and power efficiency.

  14. Pyrolysis of Cigarette Ingredients Labelled with Stable Isotopes

    Directory of Open Access Journals (Sweden)

    Stotesbury S

    2014-12-01

    Full Text Available It is important to know how tobacco additives behave when cigarettes are smoked, whether they transfer intact to the smoke or whether there is any decomposition during smoking. Pyrolysis-GC-MS is a technique that can be focussed upon the effects of combustion from a single material free from interference from the complex mixture of different components present in the smoke. However, because pyrolysis is a model technique, the results need to be validated by comparison with cigarette smoke chemistry. In a previous paper we presented such a method for modelling the smoke chemistry from a burning cigarette using pyrolysis-GC-MS. The transfer and the extent of degradation of anisole, p-anisaldehyde, benzaldehyde, isoamylisovalerate, methyl trans-cinnamate and vanillin within a burning cigarette were estimated using this pyrolysis method. When these data were compared with results from smoke studies from 14C-analogues of the materials, the high levels of transfer predicted by pyrolysis were found to be generally consistent with the smoke chemistry data. However, there were still two outstanding issues. Firstly, there was some ambiguity in the labelled study about whether vanillin actually transferred without degradation or not. Furthermore, the results from the 14C-labelled study showed a greater extent of degradation for p-anisaldehyde than that indicated from the pyrolysis experiments. The purpose of the current study was to present some new information obtained to address these questions by better understanding the effect upon the smoke chemistry from adding vanillin and p-anisaldehyde, and the relationship between the smoke chemistry and the pyrolysis results. Components were identified in the smoke from cigarettes loaded with p-anisaldehyde and vanillin labelled with 18O and 13C. The extent of degradation from each additive was estimated by identifying labelled degradation products in the smoke. Because there was a clear distinction between the

  15. Consumer's evaluation of the effects of gamma irradiation and natural antioxidants on general acceptance of frozen beef burger

    Science.gov (United States)

    Trindade, R. A.; Lima, A.; Andrade-Wartha, E. R.; Oliveira e Silva, A. M.; Mancini-Filho, J.; Villavicencio, A. L. C. H.

    2009-04-01

    The effect of addition of rosemary and oregano extracts on the sensory quality of irradiated beef burger was investigated. Batches of beef burgers were prepared with 400 ppm of rosemary or oregano extract and a group prepared with 200 ppm of synthetic butyl-hydroxytoluene (BHT)/butyl-hydroxy-anisol (BHA) was used as a control. Half of each formulation was irradiated at the maximum dose allowed for frozen meat (7 kGy). Samples were kept under frozen conditions (-20 °C) during the whole storage period, including during irradiation. Two analyses were performed after 20 and 90 days to verify the influence of the addition of the different types of antioxidants and the effect of irradiation and storage time on the acceptance of the product. Thirty-three and thirty-four untrained panelists were invited to participate in the first and second test, respectively. A structured hedonic scale ranging from 1 to 9 points was used in both analyses. BHT/BHA formulation obtained the highest score (6.73) and regarding the natural antioxidants, oregano received better acceptance (6.36). Irradiated samples formulated with oregano received a lower score, 6.03 in the first test and 5.06 in the second one, compared to the non-irradiated sample (6.36 and 5.79). In the second test (90 days), the sample formulated with BHT/BHA and which was irradiated received a higher score (6.59) when compared to the non-irradiated one (5.85). In both tests, the irradiated samples formulated with rosemary extract obtained a better score compared to the non-irradiated one, the scores being 5.00-3.82 and 5.00-3.76 in the first and second test, respectively. Our results allowed us to conclude that the natural antioxidants, rosemary and oregano extracts, present a good alternative for replacing synthetic additives in food industries, and that the irradiation process, in some cases, may help to enhance the sensory quality of food.

  16. Bioblendstocks that Enable High Efficiency Engine Designs

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, Robert L.; Fioroni, Gina M.; Ratcliff, Matthew A.; Zigler, Bradley T.; Farrell, John

    2016-11-03

    The past decade has seen a high level of innovation in production of biofuels from sugar, lipid, and lignocellulose feedstocks. As discussed in several talks at this workshop, ethanol blends in the E25 to E50 range could enable more highly efficient spark-ignited (SI) engines. This is because of their knock resistance properties that include not only high research octane number (RON), but also charge cooling from high heat of vaporization, and high flame speed. Emerging alcohol fuels such as isobutanol or mixed alcohols have desirable properties such as reduced gasoline blend vapor pressure, but also have lower RON than ethanol. These fuels may be able to achieve the same knock resistance benefits, but likely will require higher blend levels or higher RON hydrocarbon blendstocks. A group of very high RON (>150) oxygenates such as dimethyl furan, methyl anisole, and related compounds are also produced from biomass. While providing no increase in charge cooling, their very high octane numbers may provide adequate knock resistance for future highly efficient SI engines. Given this range of options for highly knock resistant fuels there appears to be a critical need for a fuel knock resistance metric that includes effects of octane number, heat of vaporization, and potentially flame speed. Emerging diesel fuels include highly branched long-chain alkanes from hydroprocessing of fats and oils, as well as sugar-derived terpenoids. These have relatively high cetane number (CN), which may have some benefits in designing more efficient CI engines. Fast pyrolysis of biomass can produce diesel boiling range streams that are high in aromatic, oxygen and acid contents. Hydroprocessing can be applied to remove oxygen and consequently reduce acidity, however there are strong economic incentives to leave up to 2 wt% oxygen in the product. This oxygen will primarily be present as low CN alkyl phenols and aryl ethers. While these have high heating value, their presence in diesel fuel

  17. Thermal Decomposition Mechanisms of Lignin Model Compounds: From Phenol to Vanillin

    Science.gov (United States)

    Scheer, Adam Michael

    Lignin is a complex, aromatic polymer abundant in cellulosic biomass (trees, switchgrass etc.). Thermochemical breakdown of lignin for liquid fuel production results in undesirable polycyclic aromatic hydrocarbons that lead to tar and soot byproducts. The fundamental chemistry governing these processes is not well understood. We have studied the unimolecular thermal decomposition mechanisms of aromatic lignin model compounds using a miniature SiC tubular reactor. Products are detected and characterized using time-of-flight mass spectrometry with both single photon (118.2 nm; 10.487 eV) and 1 + 1 resonance-enhanced multiphoton ionization (REMPI) as well as matrix isolation infrared spectroscopy. Gas exiting the heated reactor (300 K--1600 K) is subject to a free expansion after a residence time of approximately 100 micros. The expansion into vacuum rapidly cools the gas mixture and allows the detection of radicals and other highly reactive intermediates. By understanding the unimolecular fragmentation patterns of phenol (C6H5OH), anisole (C6H 5OCH3) and benzaldehyde (C6H5CHO), the more complicated thermocracking processes of the catechols (HO-C 6H4-OH), methoxyphenols (HO-C6H4-OCH 3) and hydroxybenzaldehydes (HO-C6H4-CHO) can be interpreted. These studies have resulted in a predictive model that allows the interpretation of vanillin, a complex phenolic ether containing methoxy, hydroxy and aldehyde functional groups. This model will serve as a guide for the pyrolyses of larger systems including lignin monomers such as coniferyl alcohol. The pyrolysis mechanisms of the dimethoxybenzenes (H3C-C 6H4-OCH3) and syringol, a hydroxydimethoxybenzene have also been studied. These results will aid in the understanding of the thermal fragmentation of sinapyl alcohol, the most complex lignin monomer. In addition to the model compound work, pyrolyisis of biomass has been studied via the pulsed laser ablation of poplar wood. With the REMPI scheme, aromatic lignin decomposition

  18. Analyzing sites of OH radical attack (ring vs. side chain) in oxidation of substituted benzenes via dual stable isotope analysis (δ{sup 13}C and δ{sup 2}H)

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ning [Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318 Leipzig (Germany); Geronimo, Inacrist; Paneth, Piotr [Institute of Applied Radiation Chemistry, Lodz University of Technology, Żeromskiego 116, 90-924 Łódź (Poland); Schindelka, Janine; Schaefer, Thomas; Herrmann, Hartmut [Department of Chemistry, Leibniz Institute for Tropospheric Research (TROPOS), Permoserstraße 15, 04318 Leipzig (Germany); Vogt, Carsten [Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318 Leipzig (Germany); Richnow, Hans H., E-mail: hans.richnow@ufz.de [Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318 Leipzig (Germany)

    2016-01-15

    OH radicals generated by the photolysis of H{sub 2}O{sub 2} can degrade aromatic contaminants by either attacking the aromatic ring to form phenolic products or oxidizing the substituent. We characterized these competing pathways by analyzing the carbon and hydrogen isotope fractionation (ε{sub C} and ε{sub H}) of various substituted benzenes. For benzene and halobenzenes that only undergo ring addition, low values of ε{sub C} (− 0.7‰ to − 1.0‰) were observed compared with theoretical values (− 7.2‰ to − 8‰), possibly owing to masking effect caused by pre-equilibrium between the substrate and OH radical preceding the rate-limiting step. In contrast, the addition of OH radicals to nitrobenzene ring showed a higher ε{sub C} (− 3.9‰), probably due to the lower reactivity. Xylene isomers, anisole, aniline, N,N-dimethylaniline, and benzonitrile yielded normal ε{sub H} values (− 2.8‰ to − 29‰) indicating the occurrence of side-chain reactions, in contrast to the inverse ε{sub H} (11.7‰ to 30‰) observed for ring addition due to an sp{sup 2} to sp{sup 3} hybridization change at the reacting carbon. Inverse ε{sub H} values for toluene (14‰) and ethylbenzene (30‰) were observed despite the formation of side-chain oxidation products, suggesting that ring addition has a larger contribution to isotope fractionation. Dual element isotope slopes (∆ δ{sup 2}H/∆δ{sup 13}C) therefore allow identification of significant degradation pathways of aromatic compounds by photochemically induced OH radicals. Issues that should be addressed in future studies include quantitative determination of the contribution of each competing pathway to the observed isotope fractionation and characterization of physical processes preceding the reaction that could affect isotope fractionation. - Highlights: • Isotope fractionation to investigate photoreaction pathways of substituted benzenes • Normal {sup 13}C AKIE and inverse {sup 2}H AKIE for

  19. Solid Phase Synthesis and Anti-microbial Activities of the Antibacterial Peptide IB-367%抗菌肽IB-367的固相合成与抑菌活性

    Institute of Scientific and Technical Information of China (English)

    王小青; 高杨; 尹志峰; 宫闻婧; 赵红玲; 王良友

    2016-01-01

    采用固相合成方法,以Rink Amide树脂为载体,Fmoc保护氨基酸为原料,经苯并三唑-1-四甲基六氟磷酸酯( HBTU)/N,N-二异丙基乙胺( DIEA)缩合,三氟乙酸/苯甲硫醚/乙二硫醇/苯甲醚裂解体系脱除保护基制得IB-367线性肽(4);4经双氧水氧化制得IB-367一环肽(5);5经碘乙醇溶液氧化合成抗菌肽IB-367(6),收率34.1%,纯度>95.0%,其结构经MS(ESI)和氨基酸组成分析确证。抑菌活性研究结果表明:6对大肠杆菌和金黄色葡萄球菌的最小抑菌浓度为5.0μg· mL-1。%The linear peptides of IB-367(4) was synthesized according to its peptide sequence by con-densation with O-( benzotriazol-yl )-N, N, N′, N′-tetramethy-luronium ( HBTU )/N-Ethyldiisopropyl-amine( DIEA) and deprotection with trifluoroacetic acid/thioanisole/1,2-ethanedithiol/anisole, using rink amide resin as the solid supporter , and Fmoc-amino acids as raw materials .The cyclic peptide of IB-367(5) was formed by oxidation of 4 with H2O2.The antibacterial peptide IB-367(6) with yield of 34.1%and purity>95.0% was obtained by oxidation of 5 with I2 .The structure was confirmed by MS(ESI) and amino acid composition analysis .MIC of 6 on Escherichia coli and Staphylococcus aureus was 5.0 μg· mL-1 .

  20. Emplacement Ages and Geochemical Characteristics of Grabbroic Intrusions and Prospecting Orientation of Related Deposit in Luodian, Guizhou Province

    Institute of Scientific and Technical Information of China (English)

    FANG Weixuan; HU Ruizhong; SU Wenchao; XIAO Jiafei

    2008-01-01

    Emplacement ages, geochemical characteristics and analysis of continental dynamics ongabbroic intrusions in Luodian County, Guizhou Province, have been discussed based on studies ofisotopic chronology (the whole-rock Sm-Nd and Rb-Sr isochron methods), major elements, traceelements and PGE. Intrusive activities of the gabbroic intrusions in the study area took place during theLate Yanshanian Orogenic Movement (the Cretaceous Period), as indicated by the Sm-Nd isochronages (t)=(99.6±4.5) (2σ) Ma and by the Rb-Sr isochron ages t=(97±1.6) (2o) Ma. The gabbroic intrusionsare attached to mafic rocks in cal-alkaline basaltic series. They occurred as dikes and might be formedunder an extensional background of the continent. Differentiation of their magmatic crystallizationresulted in obvious zonation of petrography. In the gabbroic intrusions of this study, large ion lithophileelements and LREE are enriched, and the chondrite-normalized REE distribution pattern is leftwardinclined without anomalies of δCe or δEu, and there are high concentrations of PGE and ratios of Pd/Ir(averaging 4.21). All of these imply that their source areas may be basaltic magma in the upper mantlewith high-level partial melting, derived from EMl-type enriched mantle. It is different from Emeishanbasalt, which may be related to the upper mantle at low-grade partial melting. Emplacementmechanism of the gabbroic intrusions in this study may suppose to be asthenosphere upheaving as anisolated hot wave in the presence of mantle fluid, resulting in basaltic magma intruded into thecontinental crust as a diapiric intrusion. Therefore, uplifting of faulting-block and extensionaldeformation could take place in the shallow part of the continental crust while vertical amassing andaccretion of magmatic materials in the deep part of the continental crust. These special processes couldsupposed to be a special background of continental dynamics for this large-scale epithermalmetaliogenic domain, such as Au

  1. From biomass to fuels: hydrotreating of oxygen-containing feeds on a CoMo/Al{sub 2}O{sub 3} hydrodesulfurization catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Viljava, T.-R.

    2001-07-01

    thus facilitating the adsorption of the reactant on the active site of the catalyst. Otherwise, the HDS rate declined due to strong competitive adsorption of the oxygen-containing compounds on the active sites of the catalyst, and due to the formation of less reactive sulfur compounds via methyl transfer from the methoxy groups to sulfur. In conclusion, simultaneous hydrotreating of sulfur- and oxygen-containing feeds leads to strong suppression of oxygen removal reactions and usually also to a decrease in the efficiency of sulfur removal. The effect of low molecular weight sulfiding agents, H{sub 2}S and CS{sub 2} on HDO of phenol and anisole was studied first in a batch and then in a flow reactor to see whether the addition of sulfiding agents might improve the stability of the presulfided catalyst without decreasing the rate and without affecting the selectivity of HDO. The HDO rate of phenol decreased noticeably in the presence of CS{sub 2}, in the batch reactor, and the selectivities of the HDO reaction paths were changed: the hydrogenation-hydrogenolysis route was less sensitive to the sulfur compound than was the CA{sub Arom}-O hydrogenolysis path. At higher concentrations of the sulfiding agent, also the hydrogenation route became inhibited. With anisole, there was an increase in the rate of demethylation to phenol, but oxygen removal was virtually unaffected. In the flow reactor studies, the formation of hydrogenated HDO products of phenol remained constant up to the highest concentration of H{sub 2}S in the feed, but a dramatic decrease in the yield of the aromatic reaction product occurred already at low concentrations of H{sub 2}S. Selective inhibition of one of the HDO paths confirmed the presence of at least two kinds of active sites on the catalyst. This means that addition of an inhibitor can be used to adjust the product distribution of HDO in process scale. However, the presulfided catalyst deactivated with time on stream also in the presence of

  2. 热力学数学模型对塑料中化学物向食品模拟液中迁移平衡时分配系数的预测研究%Study of predicting equilibrium partition coefficient of migrants in food simulants from plastic by thermodynamic mathematical modeling

    Institute of Scientific and Technical Information of China (English)

    肖少军; 张钦发; 向红; 范小平; 岳淑丽

    2014-01-01

    目的:分配系数能够直接反映出塑料包装材料中有害化学物向食品迁移的水平,研究分配系数与塑料包装材料、迁移物及食品(模拟物)三者之间的关系有重要意义。方法以 Scatchard-Hildebrand 统计热力学理论为基础,从热力学平衡角度分析了化学物在包装材料/食品体系中的迁移和分配过程,建立了一个预测化学物迁移平衡时分配系数的热力学数学模型。通过所建立的初级数学模型对聚乙烯薄膜中四种抗氧化剂,即2,6-二叔丁基-4-甲基苯酚(BHT)、二丁基羟基茴香醚(BHA)、Irganox1010和 Irganox1076向脂肪类食品模拟物异辛烷迁移平衡时状态进行模拟计算,并与已公开发表的实验数据进行了对比。结果聚乙烯薄膜中四种抗氧剂向异辛烷中迁移平衡的分配系数模拟值与实验值随温度变化趋势一致。结论该热力学模型符合迁移理论,对PE/抗氧剂/脂肪类食品体系分配系数的预测有一定的适用性。%Objective Partition coefficient can directly reflect the migration level of the compounds from plastic package materials to food, it is important to study the relationship between the partition coefficient and plastic materials, the migrates and the food(simulant). Methods Being based on the Scatchard-Hildebrand sta-tistical thermodynamic theory, the processes of the compounds migrate and distribute in packaging material/food system were analyzed, and a thermodynamic mathematical model which can predict the equilibrium partition coefficient of migrants was established. The state of migration balance of four antioxidants (2,6-di-tert-butyl-4-methyl phenol, dibutyl hydroxyl anisole, Irganox 1010 and Irganox 1076) from PE to isooctane was simulated through the mathematical model, and the values were compared with the published experimental data. Results The trends with temperature of the simulate partition coefficients of four antioxidants in PE migrate to isooctane

  3. 链状双苯基噁二唑基乙烯光化学性质的研究%Study on the Photochemical Properties of Chain Linked Bis(Phenyloxadiazoly)ethenes

    Institute of Scientific and Technical Information of China (English)

    郑艳; 赵抒娜; 张文勤

    2001-01-01

    1,n-bis[trans-4-[2-[2-(5-pheny1-1,3,4-oxadiazoly)]etheny1]phenoxy]alkanes(n=3,4,6),2,2′-bis[trans-4-[2-[2-(5-pheny1-1,3,4-oxadiazoly)]etheny1] phenoxy]ethy1 ether (D) and their model compound trans-4-[2-[2-(5- pheny1-1,3,4-oxadiazoly)]etheny1]anisole (E) were synthesized. Their structures were identified by elemental analysis, IR, UV,1H NMR, 13C NMR and MS. UV spectra were used to illustrate their photochemical properties under the irradiation of high pressure mercury lamp. It was found that A-D undergo two kinds of reactions, the trans-cis isomerization and (2+2) intramolecular photodimerization. The former is fast and reversible, but the later is slow and irreversible. The intramolecular photodimers of A-D can photolysis easily under the irradiation of low pressure mercury lamp. Furthermore, The reversible reaction between the intramolecular photodimerization of A-D and the photolysis of the formed dimers can undergo many times with high reproducibility which indicates that these sort of compounds have potential utilization in the field of photo-info memory.%本文合成了1,n-双[4-[2-[2-(5-苯基-1,3,4-噁二唑基)]乙烯基]苯氧基]烷烃(n分别为3,4,6)和2,2′-双[4-[2-[2-(5-苯基-1,3,4-噁二唑基)]乙烯基]苯氧基]乙醚4个未见文献报导的链状双杂芳基乙烯化合物及其参比物4-[2-[2-(5-苯基-1,3,4-噁二唑基)]乙烯基]苯甲醚。用元素分析、紫外、红外、核磁和质谱表征了化合物的结构并用紫外吸收光谱跟踪研究了其在稀溶液中的光化学性质。结果发现:上述化合物在高压汞灯照射下可同时发生反顺异构化和[2+2]分子内光二聚两种反应,前者迅速可逆,后者缓慢且不可逆。其分子内光二聚体在短波长紫外光照射下极易进行逆[2+2]光解开环反应而得到原来的化合物。另外,上述化合物的分子内光二聚反应和光解开环反应可反复进行多次,再现性较好,此类化

  4. Fracture-induced mechanophore activation and solvent healing in poly(methyl methacrylate)

    Science.gov (United States)

    Celestine, Asha-Dee N.

    of the crack tip. Control specimens in which the mechanophore is absent or tethered in positions in which no mechanochemical activation is expected are also tested and exhibit no change in color or fluorescence intensity with crack propagation. The relationship between fracture-induced mechanophore activation in rubber toughened SP-PMMA and the strain and stress ahead of the propagating crack is also studied. SP activation is again detected and quantified by in situ fluorescence imaging. Digital Image Correlation (DIC) is used to measure the strain ahead of the crack tip. The corresponding stress is generated through the use of the Hutchinson-Rice-Rosengren (HRR) singularity field equations. Mechanophore activation ahead of the crack tip is shown to follow a power law distribution that is closely aligned with strain. The potential of SP as a damage sensor is explored further by incorporating the spiropyran into the core of rubber nanoparticles. SP-linked rubber nanoparticles are synthesized using a seeded emulsion polymerization process and incorporated into cross-linked PMMA at a concentration of 5 wt%. Cylindrical specimens are torsion tested and the activation of the SP within the nanoparticles is monitored via full field fluorescence imaging. SP activation within the core is shown to increase with shear strain. Autonomous damage repair in PMMA is also investigated. The first demonstration of fully autonomous self-healing in PMMA is achieved through the use of solvent microcapsules. Solvent microcapsules with a PMMA-anisole liquid core are prepared and embedded within a linear PMMA matrix. Specimens of the microcapsule-loaded material are then fabricated for Double Cleavage Drilled Compression (DCDC) fracture testing. The DCDC specimens, containing increasing concentrations of solvent microcapsules, are tested and then allowed to heal for a fixed period of time before a second DCDC test. The healing efficiency of each material system is evaluated based on the

  5. Simultaneous determination of eight additives in polymer food packaging materials by ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry%超高效液相色谱-串联质谱法同时测定聚合物食品包装材料中8种添加剂

    Institute of Scientific and Technical Information of China (English)

    张旭龙; 刘银; 巩治国; 王鹏举; 王吉德; 封顺

    2014-01-01

    建立了同时测定聚合物食品包装材料中8种常用添加剂 Irgafos 168、Irganox 1010、Irganox 1076、丁基羟基茴香醚(BHA)、没食子酸丙酯(PG)、没食子酸十二酯( DG)、叔丁基对苯二酚( TBHQ)和苯三唑甲酚( UV-326)的超高效液相色谱-串联质谱方法。试样以二氯甲烷为溶剂进行超声提取;采用 Waters BEH-C18柱(50 mm ×2.1 mm,1.7μm)分离,以0.05%甲酸水溶液和甲醇为流动相进行梯度洗脱;采用电喷雾离子源正、负离子切换模式和多反应监测模式进行检测。8种添加剂在相应的质量浓度范围内定量离子的峰面积与质量浓度均呈良好线性关系(相关系数 R2均大于0.993),回收率为63.9%~127.0%,相对标准偏差(RSD,n =6)≤15.8%,检出限( S / N =3)为0.13~5.50μg / L,定量限(S / N =10)为0.45~17.50μg / L。该方法简便快捷、灵敏度高,适合食品包装材料中常用添加剂的分析测定。%An ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS / MS)method was proposed for the simultaneous determination of eight additives ( Irgafos 168(tri(2. 4-di-tert-butylphenyl)phosphite),Irganox 1076(octadecyl-β-(4-hydroxy-3, 5-di-tert-butyl- phenyl)propionate),Irganox 1010(pentaerythritol tetrakys 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate),BHA( butyl hydroxy anisole),TBHQ( tertiary butylhydroqui-none),PG( propyl gallate),DG( dodecyl gallate),UV-326( 2-( 2′-hydroxyl-3′-tert-butyl-5′-methylphenyl)-5-chlorobenzotriazole ) in food packaging materials. After extracted by chlo-romethane through ultrasonic extraction,the samples were analyzed by UPLC-MS / MS. The chromatographic conditions were optimized,and the best separation was obtained on a Waters BEH-C18 column(50 mm×2. 1 mm,1. 7 μm)with gradient elution of 0. 05% acetic acid solu-tion and methanol. The analysis was performed by UPLC-MS / MS with electrospray ionization (ESI)source in

  6. Catalytic hydrothermal gasification of biomass for the production of synthetic natural gas[Dissertation 17100

    Energy Technology Data Exchange (ETDEWEB)

    Waldner, M. H.

    2007-07-01

    , phenol, and anisole) that approximates hydrolyzed wood served as feed. The skeletal nickel catalysts turned out to be active but not stable, as they deactivated within a few hours. The attempt to stabilize them by co-doping of other metals (Ru, Mo, Cu) was not successful. Ru/TiO{sub 2} was not active enough, but Ru/C completely gasified the mixture at high space velocities over a period of more than 200 hours; the product gas composition corresponded at all times to the thermodynamic equilibrium composition. This catalyst was tested for its tolerance towards sulfate, which turned out to be low: the addition of a few ppm to the feed led to a deactivation within hours. The deactivation mechanism was identified as chemical poisoning. The poisoning species which is present in situ in the hydrothermal environment (sulfate vs. sulfide) is not clear. The experimental evidence can be explained by both hypotheses. A heating system for quartz capillaries rendered the visual examination of hydrothermal processes possible. Due to the required low amounts of feed material (a few hundred milligrams) and frequent capillary explosions, the usage of the system was discontinued. The conveying of solid containing slurries on the laboratory scale turned out to remain an unsolved problem. Thus, only liquid type biomass can be fed with the process demonstration unit that was built. A suitable feedstock was found with palm oil pyrolysis condensate, a problematic waste stream very common in Indonesia, that has a high organic content (exceeding 40 wt %). Preliminary gasification experiments with ethanol and salt separation experiments with sodium sulfate were successful. (author)

  7. Catalytic hydrothermal gasification of biomass for the production of synthetic natural gas[Dissertation 17100

    Energy Technology Data Exchange (ETDEWEB)

    Waldner, M. H.

    2007-07-01

    , phenol, and anisole) that approximates hydrolyzed wood served as feed. The skeletal nickel

  8. 结构明确的可降解醛基功能化含糖纳米微球的制备%PREPARATION OF WELL-DEFINED AND DEGRADABLE ALDEHYDE-FUNCTIONALIZED GLYCOPOLYMERIC NANOSPHERES

    Institute of Scientific and Technical Information of China (English)

    肖乃玉; 钟乐; 翟万京; 白卫东

    2012-01-01

    选择双硫代苯乙酸-1-苯基乙酯(PEPD)为RAFT试剂、以过氧化二异丙苯(DCP)为引发剂、在130℃下,茴香醚中实现了1,2:3,4-di-O-异亚丙基-6-O-(2 ’-甲醛-4'-苯乙烯基)-D-半乳糖(IVDG)和5,6-苯基-2-亚甲基-1,3-二氧七环(BMDO)的“活性”/可控RAFT自由基共聚合.Mn基本上随单体转化率线性增加,整个反应过程保持较窄的分子量分布(Mw/Mn~1.4),表明以上自由基共聚合体系呈现可控特征.1H-NMR的分析进一步证实了聚合物链的末端精细结构.此外,该共聚物经KOH处理后,聚合物的分子量很明显地向低分子量部分移动,且分布变宽,表明IVDG-BMDO共聚物是可以水降解的.经88%甲酸处理后,脱去保护基团,形成两亲性共聚物,该两亲性共聚物不需要外加乳化剂,在水中能够自组装形成含有大量半乳糖的、可生物降解的、醛基功能化的纳米微球.%The "living'Vcontrolled radical copolymerization of 1,2;3 ,4-di-0-isopropylidene-6-0-(2'-formyl-4'-vinylphenyl)-D-galactopyranose ( IVDG ) and 5 , 6-benzo-2-methylene-l , 3-dioxepane ( BMDO ) , was successfully achieved using dicumyl peroxide ( DCP) as the initiator and 1 -phenylethyl phenyldithioacetate (PEPD) as the reversible addition-fragmentation chain transfer (RAFT) agent at 130℃ in anisole. The number-average molecular weight of the obtained copolymers increased in direct proportion to the monomer conversion, and the molecular weight distribution was narrow ( polydispersity index < 1.4). Various copolymers of BMDO with IVDG were synthesized by changing the molar ratio of the two monomers in the initial feed using PEPD as chain transfer reagent under RAFT reaction conditions. There was an increase in the molecular weight from 5. 2×103 to 1. 8×104 on increasing the molar ratio of IVDG: BMDO from 20:80 to 70: 30. In general,the molecular weight of the polymers increased with increase in the amount of IVDG in the copolymers. Moreover,the copolymer

  9. Activation and deactivation of neutral palladium(II) phosphinesulfonato polymerization catalysts

    KAUST Repository

    Rünzi, Thomas

    2012-12-10

    polymerization filtrates indicate the presence of (odd- and even-numbered alkyl)(anisyl)phosphine sulfonates (14) and their respective phosphine oxides (15). Furthermore, 2-(vinyl)anisole was detected in NMR tube and reactor polymerizations, which results from ethylene insertion into a palladium-anisyl bond and concomitant β-hydride elimination. In addition to these scrambling reactions, formation of alkanes or fully saturated polymer chains, bis(chelate)palladium complexes [κ2-P,O]2Pd, and palladium black was identified as an irreversible catalyst deactivation pathway. This deactivation proceeds by reaction of palladium alkyl complexes with palladium hydride complexes [κ2-P,O]Pd(H)(L) or by reaction with the free ligand H[P,O] generated by reductive elimination from [κ2-P,O]Pd(H)(L). The model hydride complex 1-H-P tBu3 has been synthesized in order to establish whether 1-H-PtBu3 or H[P,O] is responsible for the irreversible catalyst deactivation. However, upon reaction with 1-(13)CH 3-L or 1-CH2CH3-PPh3, both 1-H-PtBu3 and H[P,O] result in formation of methane or ethane, even though H[P,O] reacts faster than 1-H-PtBu3. DFT calculations show that reductive elimination to form H[P,O] and (alkyl)[P,O] from 1-H/(alkyl)-PtBu3 is kinetically accessible, as is the oxidative readdition of the P-H bond of H[P,O] and the P-anisyl bond of (alkyl)[P,O] to [Pd(PtBu3)2]. These calculations also indicate that for a reaction sequence comprising reductive elimination of H[P,O] from 1-H-PtBu3 and reaction of H[P,O] with 1-CH3-PtBu3, 1-CH3-dmso, or 1-CH2CH3-PPh3 to form methane or ethane, the rate-limiting step is reductive elimination of H[P,O] with a barrier of 124 kJ mol-1. However, a second reaction coordinate was found for the reaction of 1-H-PtBu3 with 1-CH3-P tBu3 or 1-CH3-dmso, which evolves into bimetallic transition-state geometries with a nearly linear H-(CH 3)-Pd alignment and which exhibits a barrier of 131 or 95 kJ mol -1 for the formation of methane. © 2012 American Chemical

  10. 华山松大小蠹成虫粪便挥发性物质分析%Volatile Compounds in the Frass of Adult Chinese White Pine Beetle

    Institute of Scientific and Technical Information of China (English)

    吴绍平; 陈辉; 吴琼

    2012-01-01

    Volatile compounds from phloem of healthy Chinese white pine (Pinus armandi Franch) and fresh frass of Chinese white pine beetle (Dendroctonus armandi Tsai et Li) were extracted by solid-phase microextraction and analyzed by gas chromatography-mass spectrometry (GC-MS). The results show that the most substances were sesquitertenes, followed by monoterpenes, no diterpenes were detected in frass and phloem. There was significant difference both in constituents and contents between beetle adult frass and trees phloem. The content of monoterpene was much more but the sesquitertene was less in frass of Chinese white pine beetle than those in phloem of healthy Chinese white pine. Fifteen substances such as 6 ,6-dimethyl- bicyclo[3. 1. 1] hept-2-ene-2-carboxaldehyde, 1, 3 , 3-trimethyl-bicyclo[2. 2. l]heptan-2-ol, 2 ,3-dimethyl-tricycle [2. 2. 1. 0(2,6)] heptane-3-methanol, and so on were detected only in adult D. armandi frass, of which eight substances such as 4 ,6 ,6-trimethyl-(lS)-bicycle[3. 1. l]hept-3-en-2-one, 1,3, 3- trimethyl-bicycle[2. 2. l]heptan-2-one, pallyl-anisole were only detected in female frass and 3,7-dimeth-yl-1, 6~octadien-3-ol, 2 , 2 , 3-trimethyl-3-cyclopentene-l-acetaldehyde, butylated hydroxytoluene in male frass, which provided theoretical basis to the host selection of adults D. armandi to Chinese white pine and secretion of D. armandi pheromone.%采用固相微萃取(SPME)和气相色谱-质谱联用(GC-MS)技术,对华山松大小蠹(Dendroctonus armandi Tsai et Li)成虫新鲜粪便和华山松韧皮部中的挥发性物质进行了分析.结果表明,华山松大小蠹雌雄成虫新鲜粪便和华山松韧皮部中挥发性物质以倍半萜类物质最多,其次是单萜类物质,而未见有二萜类物质,华山松大小蠹雌雄成虫粪便和华山松韧皮部中挥发性物质在成分和含量上都有较大差别,粪便中单萜类物质含量明显高于韧皮部,而倍半萜含量则低于韧皮部.此外,6,6-二甲基-2-