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Sample records for 1-propanol

  1. Study on Ionization Energies of 3-Amino-1-propanol

    Institute of Scientific and Technical Information of China (English)

    Ke-dong Wang; Ying-bin Jia; Zhen-jiang Lai; Yu-fang Liu

    2011-01-01

    Fourteen conformers of 3-amino-1-propanol as the minima on the potential energy surface are examined at the MP2/6-311++G** level. Their relative energies calculated at B3LYP,MP3 and MP4 levels of theory indicated that two most stable conformers display the intramolecular OH…N hydrogen bonds. The vertical ionization energies of these conformers calculated with ab initio electron propagator theory in the P3/aug-cc-pVTZ approximation are in agreement with experimental data from photoelectron spectroscopy. Natural bond orbital analyses were used to explain the differences of IEs of the highest occupied molecular ortibal of conformers. Combined with statistical mechanics principles, conformational distributions at various temperatures are obtained and the temperature dependence of photoelectron spectra is interpreted.

  2. Effect Of Polar Component(1-Propanol On The RelativeVolatility Of The Binary System N-Hexane - Benzene

    Directory of Open Access Journals (Sweden)

    Khalid Farhod Chasib Al-Jiboury

    2008-01-01

    Full Text Available Vapor-liquid equilibrium data are presented for the binary systems n-hexane - 1-propanol, benzene - 1-propanol and n-hexane – benzene at 760 mm of mercury pressure. In addition ternary data are presented at selected compositions with respect to the 1-propanol in the 1-propanol, benzene, n-hexane system at 760 mmHg. The results indicate the relative volatility of n-hexane relative to benzene increases appreciably with addition of 1-propanol

  3. Dehydration pathways of 1-propanol on HZSM-5 in the presence and absence of water

    Energy Technology Data Exchange (ETDEWEB)

    Zhi, Yuchun; Shi, Hui; Mu, Linyu; Liu, Yue; Mei, Donghai; Camaioni, Donald M.; Lercher, Johannes A.

    2015-12-23

    The Brønsted acid-catalyzed gas-phase dehydration of 1-propanol (0.075-4 kPa) was studied on zeolite H-MFI (Si/Al = 26, containing minimal amounts of extraframework Al moieties) in the absence and presence of co-fed water (0-2.5 kPa) at 413-443 K. It is shown that propene can be formed from monomeric and dimeric adsorbed 1-propanol. The stronger adsorption of 1-propanol relative to water indicates that the reduced dehydration rates in the presence of water are not a consequence of the competitive adsorption between 1-propanol and water. Instead, the deleterious effect is related to the different extents of stabilization of adsorbed intermediates and the relevant elimination/substitution transition states by water. Water stabilizes the adsorbed 1-propanol monomer significantly more than the elimination transition state, leading to a higher activation barrier and a greater entropy gain for the rate-limiting step, which eventually leads to propene. In a similar manner, an excess of 1-propanol stabilizes the adsorbed state of 1-propanol more than the elimination transition state. In comparison with the monomer-mediated pathway, adsorbed dimer and the relevant transition states for propene and ether formation are similarly, while less effectively, stabilized by intrazeolite water molecules. This work was supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences, and was performed in part using the Molecular Sciences Computing Facility (MSCF) in the William R. Wiley Environmental Molecular Sciences Laboratory, a DOE national scientific user facility sponsored by the DOE’s Office of Biological and Environmental Research and located and the Pacific Northwest National Laboratory (PNNL). PNNL is operated by Battelle for DOE.

  4. Density measurements under pressure for the binary system 1-propanol plus toluene

    DEFF Research Database (Denmark)

    Zeberg-Mikkelsen, Claus Kjær; Andersen, Simon Ivar

    2005-01-01

    The density of the binary system composed of 1-propanol and toluene has been measured under pressure using a vibrating-tube densimeter. The measurements have been performed for four different compositions as well as the pure compounds at four temperatures in the range of (303.15 to 333.15) K and ...

  5. 1-phenyl-2-decanoylamino-3-morpholino-1-propanol chemosensitizes neuroblastoma cells for taxol and vincristine

    NARCIS (Netherlands)

    Sietsma, H; Veldman, Robert; Ausema, B; Nijhof, W; Kamps, W; Vellenga, E; Kok, JW

    2000-01-01

    In this study, we show that an inhibitor of glycosphingolipid biosynthesis, D,L-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), increases the chemosensitivity of neuroblastoma tumor cells for Taxol and vincristine. At noneffective low doses of Taxol or vincristine, the addition of a n

  6. Photodissociation dynamics of 1-propanol and 2-propanol at 193.3 nm

    International Nuclear Information System (INIS)

    193.3-nm photodissociation dynamics of jet-cooled 1-propanol and 2-propanol and their partially deuterated variants are examined by using the high-n Rydberg-atom time-of-flight technique. Isotope labeling studies show that O-H bond fission is the primary H-atom production channel in the ultraviolet photodissociation of both 1-propanol and 2-propanol. Center-of-mass (c.m.) product translational energy release of the RO-H dissociation channel is large, with T>=0.78 for H+1-propoxy (n-propoxy) and 0.79 for H+2-propoxy (isoproxy). Maximum c.m. translational energy release yields an upper limit of the O-H bond dissociation energy: 433±2 kJ/mol in 1-propanol and 435±2 kJ/mol in 2-propanol. H-atom product angular distribution is anisotropic (with β≅-0.79 for 1-propanol and -0.77 for 2-propanol), suggesting an electronic transition moment perpendicular to the H-O-C plane and a short excited-state dissociation lifetime (less than a rotational period). Information about photodissociation dynamics and bond energies of the partially deuterated propanols are also obtained. The 193.3-nm photodissociation dynamics of 1-propanol and 2-propanol are nearly identical to each other and are similar to those of methanol and ethanol. This indicates a common RO-H dissociation mechanism: after the nO→σ*(O-H)/3s excitation localized on the H-O-C moiety, the H atom is ejected promptly in the H-O-C plane in a time scale shorter than a rotational period of the parent molecule, and it dissociates along the O-H coordinate on the repulsive excited-state potential-energy surface with a large translational energy release

  7. Effect of calcium chloride on the isobaric vapor-liquid equilibrium of 1-propanol + water

    Energy Technology Data Exchange (ETDEWEB)

    Iliuta, M.C.; Thyrion, F.C. [Louvain Univ., Louvain-la-Neuve (Belgium). Chemical Engineering Inst.; Landauer, O.M. [Univ. Politehnica Bucharest (Romania)

    1996-05-01

    The effect of calcium chloride at salt mole fractions from 0.02 to saturation on the vapor-liquid equilibrium (VLE) of 1-propanol + water has been studied at 101.32 kPa using a modified Othmer equilibrium still. The salt exhibited a salting-out effect of the alcohol over the whole range of liquid composition, the azeotrope being eliminated at salt mole fractions greater than 0.080. A liquid phase splitting into two immiscible liquid phases on the whole range of salt concentration and over a liquid range of about 0.01--0.54 1-propanol mole fraction (salt-free basis) was observed. The results were compared with the values predicted from the extended UNIQUAC models of Sander et al. and Macedo et al. and the modified UNIFAC group-contribution model of Kikic et al.

  8. Molecular conformation and structural correlations of liquid D-1-propanol through neutron diffraction

    Indian Academy of Sciences (India)

    A Sahoo; S Sarkar; P S R Krishna; V Bhagat; R N Joarder

    2008-07-01

    An analysis of neutron diffraction data of liquid deuterated 1-propanol at room temperature to extract its molecular conformation is presented. Being a big molecule with twelve atomic sites, the analysis is tricky and needs careful consideration. The resulting molecular parameters are compared with electron diffraction (gas phase), X-ray diffraction (liquid phase) and MD simulation results. Information about the hydrogen-bonded intermolecular structure in liquid is extracted and nature of the probable molecular association suggested.

  9. Optimization of lipase-catalyzed enantioselective production of 1-phenyl 1-propanol using response surface methodology.

    Science.gov (United States)

    Soyer, Asli; Bayraktar, Emine; Mehmetoglu, Ulku

    2010-01-01

    Optically active 1-phenyl 1-propanol is used as a chiral building block and synthetic intermediate in the pharmaceutical industries. In this study, the enantioselective production of 1-phenyl 1-propanol was investigated systematically using response surface methodology (RSM). Before RSM was applied, the effects of the enzyme source, the type of acyl donor, and the type of solvent on the kinetic resolution of 1-phenyl 1-propanol were studied. The best results were obtained with Candida antartica lipase (commercially available as Novozym 435), vinyl laurate as the acyl donor, and isooctane as the solvent. In the RSM, substrate concentration, molar ratio of acyl donor to the substrate, amount of enzyme, temperature, and stirring rate were chosen as independent variables. The predicted optimum conditions for a higher enantiomeric excess (ee) were as follows: substrate concentration, 233 mM; molar ratio of acyl donor to substrate, 1.5; enzyme amount, 116 mg; temperature, 47 °C; and stirring rate, 161 rpm. A verification experiment conducted at these optimized conditions for maximum ee yielded 91% for 3 hr, which is higher than the predicted value of 83%. The effect of microwave on the ee was also investigated and ee reached 87% at only 5 min.

  10. Ultrasonic study on molecular interactions in binary mixtures of formamide with 1-propanol or 2-propanol

    Institute of Scientific and Technical Information of China (English)

    Manju Rani; Suman Gahlyan; Ankur Gaur; Sanjeev Maken

    2015-01-01

    Ultrasonic speeds have been measured at 298.15 K and 308.15 K for mixtures of formamide+1-propanol or 2-propanol. For an equimolar mixture, excess molar compressibility follows the sequence of 1-propanol N 2-propanol. The ultrasonic speed data are correlated by various correlations such as Nomoto's relation, van Dael's mixing relation and impedance dependence relation, and analyzed in terms of Jacobson's free length theory and Schaaff's collision factor theory. Excess isentropic compressibility is calculated from ex-perimental ultrasonic speed data and previously reported excess volume data. The excess molar ultrasonic speed and isentropic compressibility values are fitted to Redlich–Kister polynomial equation. Other proper-ties such as molecular association, avallable volume, free volume, and intermolecular free length are also calculated. The excess isentropic compressibility data are also interpreted in terms of graph theoretical ap-proach. The calculated isentropic compressibility values are well consistent with the experimental data. It is found that the interaction between formamide and propanol increases when hydroxyl group attached to a carbon atom has more–CH3 groups.

  11. Fluid Phase Topology of Benzene + Cyclohexane + 1-Propanol at 101.3 kPa

    Science.gov (United States)

    Andrade, R. S.; Iglesias, M.

    2015-07-01

    Isobaric vapor-liquid equilibria for the benzene + cyclohexane + 1-propanol ternary mixture were experimentally investigated at atmospheric pressure. Data were tested and considered thermodynamically consistent by means of the McDermott and Ellis method. The experimental results showed that this ternary mixture is completely miscible and exhibits three binary minimum homogeneous azeotropes and a ternary minimum azeotrope at the studied conditions. Satisfactory results were obtained for correlation of equilibrium compositions with the UNIQUAC equation and also for prediction with the UNIFAC method. In both cases, low root-mean-square deviations of the vapor mole fraction and temperature were calculated. The capability of 1-propanol as a modified distillation agent at atmospheric conditions is discussed in terms of thermodynamic topological analysis. However, because of the complex topology of the ternary mixture, it leads to a distillation scheme with two columns specifying ternary azeotrope recycling and difficult operation. Thus, this compound is not recommended as a separation agent for the binary benzene + cyclohexane azeotrope.

  12. Homogeneous nucleation rate measurements of 1-propanol in helium: the effect of carrier gas pressure.

    Science.gov (United States)

    Brus, David; Zdímal, Vladimír; Stratmann, Frank

    2006-04-28

    Kinetics of homogeneous nucleation in supersaturated vapor of 1-propanol was studied using an upward thermal diffusion cloud chamber. Helium was used as a noncondensable carrier gas and the influence of its pressure on observed nucleation rates was investigated. The isothermal nucleation rates were determined by a photographic method that is independent on any nucleation theory. In this method, the trajectories of growing droplets are recorded using a charge coupled device camera and the distribution of local nucleation rates is determined by image analysis. The nucleation rate measurements of 1-propanol were carried out at four isotherms 260, 270, 280, and 290 K. In addition, the pressure dependence was investigated on the isotherms 290 K (50, 120, and 180 kPa) and 280 K (50 and 120 kPa). The isotherm 270 K was measured at 25 kPa and the isotherm 260 K at 20 kPa. The experiments confirm the earlier observations from several thermal diffusion chamber investigations that the homogeneous nucleation rate of 1-propanol tends to increase with decreasing total pressure in the chamber. In order to reduce the possibility that the observed phenomenon is an experimental artifact, connected with the generally used one-dimensional description of transfer processes in the chamber, a recently developed two-dimensional model of coupled heat, mass, and momentum transfer inside the chamber was used and results of both models were compared. It can be concluded that the implementation of the two-dimensional model does not explain the observed effect. Furthermore the obtained results were compared both to the predictions of the classical theory and to the results of other investigators using different experimental devices. Plotting the experimental data on the so-called Hale plot shows that our data seem to be consistent both internally and also with the data of others. Using the nucleation theorem the critical cluster sizes were obtained from the slopes of the individual isotherms

  13. Intermolecular interactions in mixtures of ethyl formate with methanol, ethanol, and 1-propanol on density, viscosity, and ultrasonic data

    Science.gov (United States)

    Elangovan, S.; Mullainathan, S.

    2014-12-01

    Density (ρ), viscosity (η), and ultrasonic velocity ( U) have been measured for binary mixtures of ethyl formate with methanol, ethanol, and 1-propanol at 303 K. From the experimental data, adiabatic compressibility (β), acoustic impedance ( Z), viscous relaxation time (τ), free length ( L f), free volume ( V f), internal pressure (πi), and Gibbs free energy (Δ G) have been deduced. It is shown that strength of intermolecular interactions between ethyl formate with selected 1-alcohols were in the order of methanol < ethanol < 1-propanol.

  14. Novel Dehalogenase Mechanism for 2,3-Dichloro-1-Propanol Utilization in Pseudomonas putida Strain MC4

    NARCIS (Netherlands)

    Arif, Muhammad Ilan; Samin, Ghufrana; van Leeuwen, Jan G. E.; Oppentocht, Jantien; Janssen, Dick B.

    2012-01-01

    A Pseudomonas putida strain (MC4) that can utilize 2,3-dichloro-1-propanol (DCP) and several aliphatic haloacids and haloalcohols as sole carbon and energy source for growth was isolated from contaminated soil. Degradation of DCP was found to start with oxidation and concomitant dehalogenation catal

  15. PROPIEDADES VOLUMÉTRICAS DE LA MEZCLA N,NDIMETILFORMAMIDA + 1-PROPANOL A DIFERENTES TEMPERATURAS

    Directory of Open Access Journals (Sweden)

    Manuel Páez

    2011-12-01

    Full Text Available Las densidades del sistema binario N,NDimetilformamida+ 1-propanol se midieroncomo una función de la fracciónmolar a las temperaturas de (283,15;288,15; 293,15; 298,15; 303,15; 308,15y 313,15 K y 1011 bar, usando un densímetrode tubo vibratorio DMA 5000. Losdatos experimentales de densidad se utilizaronpara calcular los volúmenes molaresde exceso (VEm, volúmenes molaresparciales de exceso del soluto y del solvente( ¯VEi , volúmenes molares parcialesa dilución infinita (¯V∞i y los coeficientesviriales (bv de acuerdo con la teoría deMcMillan–Mayer, que se discutieron entérminos de las interacciones presentesen solución. Los volúmenes molaresde exceso se correlacionaron usando laecuación polinomial de Redlich–Kister.Los volúmenes molares de exceso yvolúmenes molares parciales de excesodel soluto y del solvente son negativosen todo el intervalo de fracción molar atodas las temperaturas de estudio, hechoque puede deberse a interacciones específicasentre los componentes o a la asociacióna través de fuerzas débiles.

  16. Solvatochromism and preferential solvation in mixtures of Methanol with Ethanol, 1-Propanol and 1-Butanol

    Directory of Open Access Journals (Sweden)

    Masoumeh Sayadian

    2014-12-01

    Full Text Available The spectral shift of 4-nitroaniline was determined in pure methanol, ethanol, 1-propanol and 1-butanol and binary mixtures of methanol with other 1-alkanols at 25 ⁰C by UV-vis spectroscopy. The effect of specific and non-specific solute-solvent interactions on the spectral shift was investigated by using the linear solvation energy relationship concept. A multiple linear regression analysis was used to correlate the spectral shift with microscopic Kamlet-Taft parameters (a, b and p* in pure solvents. Results indicate that the spectral shift is highly related with the specific solute-solvent interactions. In binary mixtures, a nonideal behavior of spectral shift was observed respective to the analytical mole fraction of alcohols; indicating preferential solvation. The spectral shifts were fitted to a known preferential solvation model named solvent exchange model to calculate the preferential solvation parameters. The preference of solute to be solvated by one of the solvating species relative to others was explained in terms of solvent-solvent and solute-solvent interactions.

  17. A thermodynamic study of 1-propanol-glycerol-H2O at 25 degrees C: Effect of glycerol on molecular organization of H2O

    DEFF Research Database (Denmark)

    Parsons, M.T.; Westh, Peter; Davies, J.V.;

    2001-01-01

    The excess chemical potential, partial molar enthalpy, and volume of 1-propanol were determined in ternary mixtures of 1-propanol-glycerol-H2O at 25degreesC. The mole fraction dependence of all these thermodynamic functions was used to elucidate the effect of glycerol on the molecular organization...

  18. The temperature dependent structure of liquid 1-propanol as studied by neutron diffraction and EPSR simulations

    Science.gov (United States)

    Sillrén, Per; Swenson, Jan; Mattsson, Johan; Bowron, Daniel; Matic, Aleksandar

    2013-06-01

    The structure of liquid 1-propanol is investigated as a function of temperature using neutron diffraction together with Empirical Potential Structure Refinement modelling. The combined diffraction and computer modelling analysis demonstrates that propanol molecules form hydrogen bonded clusters with a relatively wide size distribution, which broadens at lower temperatures. We find that the cluster size distribution is well described by a recently proposed statistical model for branched H-bonded networks [P. Sillrén, J. Bielecki, J. Mattsson, L. Börjesson, and A. Matic, J. Chem. Phys. 136, 094514 (2012)], 10.1063/1.3690137. The average cluster size increases from ˜3 to 7 molecules, whilst the standard deviation of the size distribution increases from 3.3 to 8.5 as the temperature is decreased from 293 to 155 K. The clusters are slightly branched, with a higher degree of branching towards lower temperatures. An analysis of the cluster gyration tensor (Rmn) reveals an average elongated ellipsoidal shape with axes having proportions 1:1.4:1.9. We find that the average radius of gyration has a cluster size dependence consistent with that of fractal clusters, Rg ∝ n1/D, with a fractal dimension D ≈ 2.20, which is close to D = 2.00 expected for an ideal random walk or D = 2.11 expected for reaction limited aggregation. The characteristic angles between the H-bonded OH-groups that constitute the clusters show only a weak temperature dependence with O-H⋯O angles becoming more narrowly distributed around 180° at lower temperatures.

  19. Enthalpies of dilution of glycine and L-alanine in aqueous 1-propanol solutions at T = 298.15 K

    International Nuclear Information System (INIS)

    The dilution enthalpies of glycine and L-alanine in aqueous 1-propanol solutions have been measured by a mixing-flow microcalorimeter at T = 298.15 K. The homogeneous enthalpic interaction coefficients of the two zwitterions have been calculated according to the analysis of the excess enthalpy suggested by Friedman [J. Solution Chem. 1 (1972) 387-390]. The enthalpic pairwise interaction coefficients h2 of glycine are negative and pass through a minimum with increasing 1-propanol content in mixed solvents, while those of L-alanine decrease from positive to negative. The variations of the enthalpic pairwise interaction coefficients are interpreted in terms of solute - solute and solute - solvent interactions

  20. Complementary vapor pressure data for 2-methyl-1-propanol and 3-methyl-1-butanol at a pressure range of (15 to 177) kPa

    Energy Technology Data Exchange (ETDEWEB)

    Bejarano, Arturo; Quezada, Nathalie [Departamento de Ingenieria Quimica y Ambiental, Universidad Tecnica Federico Santa Maria, Avda. Espana 1680, Valparaiso (Chile); Fuente, Juan C. de la [Departamento de Ingenieria Quimica y Ambiental, Universidad Tecnica Federico Santa Maria, Avda. Espana 1680, Valparaiso (Chile)], E-mail: juan.delafuente@usm.cl

    2009-09-15

    The vapor pressure of pure 2-methyl-1-propanol and 3-methyl-1-butanol, components called congeners that are present in aroma of wine, pisco, and other alcoholic beverages, were measured with a dynamic recirculation apparatus at a pressure range of (15 to 177) kPa with an estimated uncertainty <0.2%. The measurements were performed at temperature ranges of (337 to 392) K for 2-methyl-1-propanol and (358 to 422) K for 3-methyl-1-butanol. Data were correlated using a Wagner-type equation with standard deviations of 0.09 kPa for the vapor pressure of 2-methyl-1-propanol and 0.21 kPa for 3-methyl-1-butanol. The experimental data and correlation were compared with data selected from the literature.

  1. Ternary Diffusion Coefficients of 1-Hexanol-Hexane-Toluene and 1-Propanol-Water-Ethylene Glycol by Taylor Dispersion Method

    Institute of Scientific and Technical Information of China (English)

    REN Zhongqi; FEI Weiyang; Hans-Joerg Bart

    2005-01-01

    The Taylor dispersion method was used to measure diffusion coefficients of three-component liquid systems. An improved constrained nonlinear least-square method was used to evaluate the ternary diffusion coefficients directly by fitting the mathematical solutions of the dispersion equation to eluted solute peaks detected using a differential refractometer. Diffusion coefficients of the three-component system of acetone-benzene-CCl4, determined at 25℃, were used to test the procedure. The measured diffusion coefficients were compared with values obtained by optical interferometry and the diaphragm cell method. Ternary diffusion coefficients are also determinated for solutions of 1-hexanol-hexane-toluene and 1-propanol-water-ethylene glycol at 25℃, with an accuracy of approximately 0.05 m2·s-1.

  2. Prebiotic Polymerization: Oxidative Polymerization of 2,3 Dimercapto-1- Propanol on the Surface of Iron(III) Hydroxide Oxide

    Science.gov (United States)

    Weber, Arthur L.

    1995-01-01

    The oxidation of 2,3-dimercapto-1-propanol by ferric ions on the surface of iron(III) hydroxide oxide (Fe(OH)O) yielded polydisulfide oligomers. This polymerization occurred readily at low dithiol concentration under mild aqueous conditions. Polydisulfide polymers up to the 15-mer were synthesized from 1 mM dithiol in 5 ml water reacted with iron(III) hydroxide oxide (20 mg, 160 micromole Fe) for 3 days under anaerobic conditions at 40 C and pH 4. About 91% of the dithiol was converted to short soluble oligomers and 9% to insoluble larger oligomers that were isolated with the FE(OH)O phase. Reactions carried out at the same ratio of dithiol to FE(OH)O but at higher dithiol concentrations gave higher yields of the larger insoluble oligomers. The relationship of these results to prebiotic polymer synthesis is discussed.

  3. Prebiotic polymerization: Oxidative polymerization of 2, 3-dimercapto-1-propanol on the surface of iron(III) hydroxide oxide

    Science.gov (United States)

    Weber, Arthur L.

    1995-01-01

    The oxidation of 2, 3-dimercapto-1-propanol by ferric ions on the surface of iron(III) hydroxide oxide (Fe(OH)O) yielded polydisulfide oligomers. This polymerization occurred readily at low dithiol concentration under mild aqueous conditions. Polydisulfide polymers up to the 15-mer were synthesized from 1 mM dithiol in 5 ml water reacted with iron(III) hydroxide oxide (20 mg, 160 micromole Fe) for 3 days under anaerobic conditions at 40 C and pH 4. About 91% of the dithiol was converted to short soluble oligomers and 9% to insoluble larger oligomers that were isolated with the Fe(OH)O phase. Reactions carried out at the same ratio of dithiol to Fe(OH)O but at higher dithiol concentrations gave higher yields of the larger insoluble oligomers. The relationship of these results to prebiotic polymer synthesis is discussed.

  4. Molecular probe dynamics and free volume in organic glass-formers and their relationships to structural relaxation: 1-propanol

    International Nuclear Information System (INIS)

    A joint study of the rotational dynamics and free volume in amorphous 1-propanol (1-PrOH) as a prototypical monohydroxy alcohol by electron spin resonance (ESR) or positron annihilation lifetime spectroscopy (PALS), respectively, is reported. The dynamic parameters of the molecular spin probe 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) and the annihilation ones of the atomic ortho-positronium (o-Ps) probe as a function of temperature are compared. A number of coincidences between various effects in the ESR and PALS responses at the corresponding characteristic ESR and PALS temperatures were found suggesting a common origin of the underlying dynamic processes that were identified using viscosity (VISC) in terms of the two-order parameter (TOP) model and broadband dielectric spectroscopy (BDS) data. (paper)

  5. Aqueous Solubility of Piperazine and 2-Amino-2-methyl-1-propanol plus Their Mixtures Using an Improved Freezing-Point Depression Method

    DEFF Research Database (Denmark)

    Fosbøl, Philip Loldrup; Neerup, Randi; Waseem Arshad, Muhammad;

    2011-01-01

    In this work the solid–liquid equilibrium (SLE) and freezing-point depression (FPD) in the electrolytic binary aqueous systems piperazine (PZ, CAS No. 110-85-0) and aqueous 2-amino-2-methyl-1-propanol (AMP, CAS No. 124-68-5) were measured. The FPD and solubility were also determined in the ternar...

  6. Effects of constituent ions of a phosphonium-based ionic liquid on molecular organization of H2O as probed by 1-propanol

    DEFF Research Database (Denmark)

    Morita, Takeshi; Miki, Kumiko; Ayako, Nitta;

    2015-01-01

    on the basis of 1-propanol probing methodology devised by Koga et al. The resulting characterization of the hydrophobicity/hydrophilicity is displayed on a two-dimensional map together with previous results, for a total of four cations and nine anions of typical ionic liquid (IL) constituents. The results...

  7. Viscosities and refractive indices of binary systems acetone+1-propanol, acetone+1,2-propanediol and acetone+1,3-propanediol

    Directory of Open Access Journals (Sweden)

    Živković Emila M.

    2014-01-01

    Full Text Available Viscosities and refractive indices of three binary systems, acetone+1-propanol, acetone+1,2-propanediol and acetone+1,3-propanediol, were measured at eight temperatures (288.15, 293.15, 298.15, 303.15, 308.15, 313.15, 318.15, 323.15K and at atmospheric pressure. From these data viscosity deviations and deviations in refractive index were calculated and fitted to the Redlich-Kister equation. The viscosity modelling was done by two types of models: predictive UNIFAC-VISCO and ASOG VISCO and correlative Teja-Rice and McAlister equations. The refractive indices of binary mixtures were predicted by various mixing rules and compared with experimental data. [Projekat Ministarstva nauke Republike Srbije, br. 172063

  8. Excess parameters for binary mixtures of ethyl benzoate with 1-propanol, 1-butanol and 1-pentanol at T=303, 308, 313, 318, and 323 K

    Science.gov (United States)

    Sreehari Sastry, S.; Babu, Shaik; Vishwam, T.; Parvateesam, K.; Sie Tiong, Ha.

    2013-07-01

    Various thermo-acoustic parameters, such as excess isentropic compressibility (KsE), excess molar volume (VE), excess free length (LfE), excess Gibb's free energy (ΔG*E), and excess Enthalpy (HE), have been calculated from the experimentally determined data of density, viscosity and speed of sound for the binary mixtures of ethyl benzoate+1-propanol, or +1-butanol, or +1-pentanol over the entire range of composition at different temperatures (303, 308, 313, 318 and 323 K). The excess functions have been fitted to the Redlich-Kister type polynomial equation. The deviations for excess thermo-acoustic parameters have been explained on the basis of the intermolecular interactions present in these binary mixtures.

  9. Excess parameters for binary mixtures of ethyl benzoate with 1-propanol, 1-butanol and 1-pentanol at T=303, 308, 313, 318, and 323 K

    Energy Technology Data Exchange (ETDEWEB)

    Sreehari Sastry, S., E-mail: sreeharisastry@yahoo.com [Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar, Andhra Pradesh 522 510 (India); Babu, Shaik, E-mail: babu.computers@gmail.com [Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar, Andhra Pradesh 522 510 (India); Vishwam, T., E-mail: vishwam@gitam.edu [Department of Engineering Physics, Gitam University, Hyderabad Campus, Andhra Pradesh 502 239 (India); Parvateesam, K., E-mail: kps27031966@gmail.com [Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar, Andhra Pradesh 522 510 (India); Sie Tiong, Ha., E-mail: hast@utar.edu.my [Faculty of Science, Department of Chemical Science, Universiti Tunku Abdul Rahman, Jalan Universiti, Bandar Barat, 31900 Kampar, Perak (Malaysia)

    2013-07-01

    Various thermo–acoustic parameters, such as excess isentropic compressibility (K{sub s}{sup E}), excess molar volume (V{sup E}), excess free length (L{sub f}{sup E}), excess Gibb's free energy (ΔG{sup *E}), and excess Enthalpy (H{sup E}), have been calculated from the experimentally determined data of density, viscosity and speed of sound for the binary mixtures of ethyl benzoate+1-propanol, or +1-butanol, or +1-pentanol over the entire range of composition at different temperatures (303, 308, 313, 318 and 323 K). The excess functions have been fitted to the Redlich–Kister type polynomial equation. The deviations for excess thermo–acoustic parameters have been explained on the basis of the intermolecular interactions present in these binary mixtures.

  10. Thermodynamic properties of solutions of sodium di-hydrogen phosphate in (1-propanol + water) mixed-solvent media over the temperature range of (283.15 to 303.15) K

    Energy Technology Data Exchange (ETDEWEB)

    Sadeghi, Rahmat [Department of Chemistry, University of Kurdistan, Pasdran Street, Sanandaj, Kurdistan 66135 (Iran, Islamic Republic of)], E-mail: rsadeghi@uok.ac.ir; Parhizkar, Hana [Department of Chemistry, University of Kurdistan, Pasdran Street, Sanandaj, Kurdistan 66135 (Iran, Islamic Republic of)

    2008-06-15

    The apparent molar volume and apparent molar isentropic compressibility of solutions of sodium di-hydrogen phosphate (NaH{sub 2}PO{sub 4}) in (1-propanol + water) mixed-solvent media with alcohol mass fractions of 0.00, 0.05, 0.10, and 0.15 are reported over the range of temperature (283.15 to 303.15) K at 5 K intervals. The results were fitted to a Redlich-Mayer type equation from which the apparent molar volume and apparent molar isentropic compressibility of the solutions at the infinite dilution were also calculated at the working temperature. The results show a positive transfer volume of NaH{sub 2}PO{sub 4} from an aqueous solution to an aqueous 1-propanol solution. The apparent molar isentropic compressibility of NaH{sub 2}PO{sub 4} in aqueous 1-propanol solutions is negative and it increases with increasing the concentration of NaH{sub 2}PO{sub 4}, 1-propanol, and temperature. Electrical conductivity and refractive index of the solutions are also studied at T = 298.15 K. The effects of the electrolyte concentration and relative permittivity of the medium on the molar conductivity were also investigated.

  11. Excess molar volumes and viscosities of binary mixtures of some polyethers with 1-propanol at 288.15, 298.15, and 308.15 K

    Indian Academy of Sciences (India)

    Amalendu Pal; Anil Kumar

    2004-01-01

    Excess molar volumes ($V_{m}^{E}$) and viscosities () have been measured as a function of composition for binary liquid mixtures of 1-propanol, C3H7OH, with diethylene glycol diethyl ether (bis(2-ethoxyethyl)ether), C2H5(OC2H4)2OC2H5, and diethylene glycol dibutyl ether (bis(2-butoxyethyl)ether), C4H9(OC2H4)2OC4H9, at 288.15, 298.15, and 308.15 K and at atmospheric pressure. The excess volume results included the following mixing quantities at all range of concentrations and at equimolar concentrations: , volume expansivity; ( $V^{E}_{m}$/ ), and ( /) at 298.15 K. The obtained results were then compared with the calculated values by using the Flory theory of liquid mixtures. The theory predicts the values rather well, while the calculated values of ( $V^{E}_{m}$/ ) and ( /) show variation with alkyl chain length of the polyether. The results are discussed in terms of order or disorder creation. From the viscosity data, deviations in viscosity ( ) have been calculated. These values are negative over the entire range of composition. The results for $V^{E}_{m}$, and are discussed in terms of interaction between components.

  12. Supercritical CO2 desorption of activated carbon loaded with 2,2,3,3-tetrafluoro-1-propanol in a rotating packed bed.

    Science.gov (United States)

    Tan, Chung-Sung; Lee, Pei-Lun

    2008-03-15

    Desorption of activated carbon loaded with 2,2,3,3-tetrafluoro-1-propanol (TFP) by supercritical carbon dioxide in a rotating packed bed was investigated in this study. The experimental data show that the time required to achieve complete desorption of TFP from activated carbon in a rotating packed bed was much lower than that in a static packed bed. The reduction of desorption time is attributed to the presence of centrifugal force. The supercritical CO2 desorption efficiency in a rotating packed bed was observed to increase with increasing rotation speed, pressure, and C02 flow rate. To enhance desorption efficiency, a smaller activated carbon particle size was suggested. At low operating pressures such as 8.96 and 11.72 MPa, a better desorption efficiency was found to occur at lower temperatures in a temperature range of 305-335 K. However, at high operating pressures such as 15.86 MPa, a temperature of 315 K was found to be more appropriate for desorption, as compared to other temperatures. Due to a reduction of packed bed volume and an increase in desorption efficiency, supercritical CO2 desorption in a rotating packed bed is suggested for recovering TFP from the exhaust gases. PMID:18409651

  13. Solubility and thermodynamic modeling of hydrogen sulfide in aqueous (diisopropanolamine + 2-amino-2-methyl-1-propanol + piperazine) solution at high pressure

    International Nuclear Information System (INIS)

    Highlights: • The (DIPA + AMP + Piperazine) systems are investigated. • A high pressure equilibrium cell is used for solubility measurement. • Piperazine improves H2S solubility in the (DIPA + AMP) system at high loading. • Electrolyte-NRTL is used for modeling of (H2S + DIPA + AMP + PZ) systems. - Abstract: Natural gas as a clean source of energy contains several contaminates such as CO2 and H2S that is treated through a natural gas purification unit in gas industry. Moreover, for design and construction of gas contactor equipment, it is necessary to obtain experimental values of solubility for H2S and CO2 in aqueous amine/alkanolamines. In this work, the solubility of H2S in the blended aqueous diisopropanolamine (DIPA), 2-amino-2-methyl-1-propanol (AMP) and piperazine (Pz) are measured using a static high pressure apparatus through volumetric method. The values are measured at fixed 45 mass per cent of total amine so that the solubility of H2S in the present system is investigated under isothermal conditions at T = (313.15, 328.15 and 343.15) K and in the pressure range of (0.1 to 2.1) MPa. The experimental results are presented as the partial pressure of H2S against acid gas loading (moles H2S per total moles of amine). Also for modeling the solubility of H2S in the blended amine/alkanolamines, the Electrolyte-NRTL activity coefficient function is applied to the correlation and prediction of the partial pressure of H2S versus the acid gas loading. Considering the present results at the given conditions, it is observed that in the low gas loading region, the effect of enhancing Pz on the solubility of H2S is very low, but at high gas loading the absorption of H2S is intensified by enhancing mass fraction of Pz in alkanolamine

  14. Volumetric, transport, and acoustic properties of binary mixtures of 2-methyl-1-propanol with hexadecane and squalane at T = (298.15, 303.15, and 308.15) K: Experimental results, correlation, and prediction by the ERAS model

    Energy Technology Data Exchange (ETDEWEB)

    Dubey, Gyan Prakash [Department of Chemistry, Kurukshetra University, Kurukshetra 136 119 (India)], E-mail: gyan.dubey@rediffmail.com; Sharma, Monika [Department of Chemistry, Kurukshetra University, Kurukshetra 136 119 (India); Oswal, Shantilal [R and D, Biochemistry, Span Diagnostics Ltd., 173-B, New Industrial Estate, Udhna, Surat 394 210 (India)], E-mail: oswalsl@yahoo.co.uk

    2009-07-15

    Density {rho}, speed of sound u, and viscosity {eta} of the binary systems 2-methyl-1-propanol + hexadecane and 2-methyl-1-propanol + squalane (2,6,10,15,19,23-hexamethyltetracosane) have been measured over the entire range of composition at T = (298.15, 303.15, and 308.15) K and atmospheric pressure using a vibrating tube densimeter and sound analyzer Anton Paar model DSA-5000 and Ubbelohde suspended level viscometer. Excess molar volume V{sub m}{sup E}, excess molar isentropic compressibility K{sub S,m}{sup E}, and deviations of the speed of sound u{sup D} from their ideal values u{sup id} and excess thermal expansion coefficient {alpha}{sup E} were evaluated from the experimental results obtained. These derived properties were fitted to variable-degree polynomials. Further, the Extended Real Associated Solution (ERAS) model has been applied to V{sub m}{sup E} for the present binary mixtures along with (2-methyl-1-propanol + hexane, + octane and + decane) and the findings are compared with the experimental results.

  15. Extraction separation of germanium with potassium iodide-1-propanol-germanium(Ⅳ)ternary complex%碘化钾-正丙醇-锗(Ⅳ)三元缔合物萃取分离锗

    Institute of Scientific and Technical Information of China (English)

    韩金土; 司学芝; 张会杰; 马万山

    2012-01-01

    The extraction and separation behaviors of germanium by potassium iodide - 1-propanol -germanium (Ⅳ) complex and the separation conditions of some metal ions were studied. The results showed that sodium chloride could separate the 1-propanol aqueous solution into two phases. In phase separation process, the complex[GeI6,2- ][C3H7OH2+]2 formed from GeI6,2- (which was generated from germanium(Ⅳ) and potassium iodide) and protonized 1-propanol (C3H7OH2,+) could be fully extracted by 1-propanol phase. The extraction rate of germanium(Ⅳ) was higher than 98. 4% when the concentrations of 1-propanol,potassium iodide and sodium chloride were 30%(V/V) ,8. 0 × 10-3 mol/L and 0. 20 g/mL,respectively. Meanwhile,Zn2+ ,Fe2+ ,Mg2+ ,Ni2+ ,Co2+ ,Mn2+ ,Ag+ , Al3+ and Cr3+ could not be extracted,realizing the separation of germanium(Ⅳ) from these metal ions.%探讨了碘化钾-正丙醇-锗(Ⅳ)三元缔合物萃取分离锗的行为及与一些金属离子分离的条件.结果表明,氯化钠能将正丙醇的水溶液分成两相,在分相过程中,Ge(Ⅳ)与碘化钾生成的GeI62-与质子化正丙醇(C3H7OH2+)形成的缔合物[GeI62-][C3H7OH2+]2能被正丙醇相完全萃取.当正丙醇、碘化钾和氯化钠的浓度分别为30%(V/V)、8.0×10-3 mol/L、0.20 g/mL时,Ge(Ⅳ)的萃取率达到98.4%以上,Zn2+、Fe2+、Mg2+、Ni2+、Co2+、Mn2+、Ag+、Al3+和Cr3+基本不被萃取,实现了Ge(Ⅳ)与上述金属离子的分离.

  16. Thermodynamic study of binary mixture of x{sub 1}[C{sub 6}mim][BF{sub 4}] + x{sub 2}1-propanol: Measurements and molecular modeling

    Energy Technology Data Exchange (ETDEWEB)

    Kermanpour, F., E-mail: kermanpour@basu.ac.ir [Faculty of Chemistry, Bu-Ali Sina University, Hamadan 65178-38695 (Iran, Islamic Republic of); Sharifi, T. [Faculty of Chemistry, Bu-Ali Sina University, Hamadan 65178-38695 (Iran, Islamic Republic of)

    2012-01-10

    Highlights: Black-Right-Pointing-Pointer Densities and viscosities for binary mixture of {l_brace}x{sub 1}[C{sub 6}mim][BF{sub 4}] + x{sub 2}1-propanol{r_brace} were measured at different temperatures. Black-Right-Pointing-Pointer The excess molar functions were calculated from the obtained experimental data. Black-Right-Pointing-Pointer These data were correlated with the Redlich-Kister equation and PFP model to obtain the coefficients and standard deviations. - Abstract: Densities, {rho}, and viscosities, {eta}, of pure 1-hexyl-3-methylimidazoliumtetrafluoro borate ([C{sub 6}mim][BF{sub 4}]) and 1-propanol, and their binary mixture {l_brace}x{sub 1}[C{sub 6}mim][BF{sub 4}] + x{sub 2}1-propanol{r_brace} were measured at atmospheric pressure and in the temperature range of 293.15-333.15 K. The excess molar volumes, V{sub m}{sup E}, thermal expansion coefficients, {alpha}, and their excess values, {alpha}{sup E}, isothermal coefficient of excess molar enthalpy, ({partial_derivative}H{sub m}{sup E}/{partial_derivative}p){sub T,x} and excess viscosities, {eta}{sup E}, were calculated from the experimental values of densities and viscosities. The excess molar volumes of the binary mixture are negative over the entire mole fraction range and increase with increasing temperature. Excess viscosities are negative over the entire mole fraction range of the mixture and decrease with increasing temperature. The obtained excess molar volumes and excess viscosities were correlated with the Redlich-Kister equation. The experimental results have also been used to examine the applicability of Prigogine-Flory-Patterson (PFP) theory in predicting the excess molar volume of the binary mixture. It is indicated that agreement between excess molar volumes calculated via PFP theory and the experimental results is good in all temperatures.

  17. Study on the Change of Refractive Index on Mixing, Excess Molar Volume and Viscosity Deviation for Aqueous Solution of Methanol, Ethanol, Ethylene Glycol, 1-Propanol and 1, 2, 3-Propantriol at T = 292.15 K and Atmospheric Pressure

    Directory of Open Access Journals (Sweden)

    Fardad Koohyar

    2012-08-01

    Full Text Available For aqueous solutions of methanol, ethanol, ethylene glycol, 1-propanol and 1, 2, 3-propantriol the change of refractive indices on mixing, excess molar volumes and viscosity deviations were calculated from the experimental data at 292.15 K. These experimental data (refractive indices, densities and viscosities were measured over the whole mole fractions range in atmospheric pressure and at T = 292.15 K. For these mixtures, excess thermodynamic properties have been correlated with the Redlich-Kister polynomial equation (and experimental equation to derive the coefficients and standard errors.

  18. 正丙醇和异丙醇的紫外光解动力学%Ultraviolet Photodissociation Dynamics of 1-Propanol and 2-Propanol by High-n Rydberg-Atom Time-of-flight(HRTOF) Technique

    Institute of Scientific and Technical Information of China (English)

    周卫东; 张劲松

    2002-01-01

    利用高里德堡态氢原子飞行时间(HRTOF)探测技术,研究了正丙醇和异丙醇的紫外光解动力学过程.在193.3 nm光辐射下,O-H键快速断裂过程构成主要的氢原子生成通道.伴随O-H键的碎裂,相当大的一部分能量转换成氢原子及其相应碎片的平动能(正丙醇〈fv〉=0.76; 异丙醇〈fv〉=0.78).氢原子碎片具有各向异性的角度分布;其角分布异向因子β分别为-0.79(正丙醇)和-0.77(异丙醇).研究结果表明,吸收1个193.3 nm光子后,丙醇分子跃迁到一个寿命很短的电子激发态;沿着O-H反应坐标,该激发态势能面是排斥的,因而O-H键快速断裂.此外,还得到了丙醇的O-H键离解能: (432±2)kJ/mol(正丙醇)和(433±2)kJ/mol(异丙醇).%193.3 nm photodissociation dynamics of jet-cooled 1-propanol and 2-propanol has been examined by using high-n Rydberg-atom time-of-flight (HRTOF) technique. Isotope labeling study indicates that O-H bond fission is the primary H-atom production channel. Center-of-mass (CM) product translational energy release of this channel is large, with 〈fT〉= 0.76 for H+1-propoxy and 0.78 for H+2-propoxy. Maximum CM translational energy release yields an upper limit of the O-H bond dissociation energy: (432±2)kJ/mol in 1-propanol and (433±2)kJ/mol in 2-propanol. H-atom product angular distribution is anisotropic (with β≈-0.79 for 1-propanol and -0.77 for 2-propanol), indicating a short excited-state lifetime. The 193.3 nm H-atom dissociation of both 1-propanol and 2-propanol is prompt and occurs on a repulsive excited-state potential energy surface.

  19. Thermodynamics of mixtures containing amines. XIV. C{sub pm}{sup E} of benzylamine with heptane at 293.15 K or with methanol, 1-propanol or 1-pentanol at 293.15–308.15 K

    Energy Technology Data Exchange (ETDEWEB)

    Páramo, Ricardo; Alonso, Víctor; González, Juan Antonio, E-mail: jagl@termo.uva.es; García de la Fuente, Isaías; Casanova, Carlos; Cobos, José Carlos

    2014-06-01

    Graphical abstract: - Highlights: • C{sub pm}{sup E}s are reported for benzylamine + heptane, +methanol, +1-propanol, +1-pentanol systems. • The heptane solution shows a W-shaped C{sub pm}{sup E} concentration dependence. • This reveals the existence of strong non-random effects in that mixture. • Systems with 1-alkanols are characterized by large and positive C{sub pm}{sup E} values. • This remarks that self-association/solvation effects are predominant in such systems. - Abstract: Molar excess heat capacities, C{sub pm}{sup E}, are reported for the benzylamine + heptane mixture at 293.15 K and for methanol, 1-propanol or 1-pentanol + benzylamine systems at 293.15–308.15 K. These values were determined from isobaric molar heat capacities obtained with a Setaram Micro DSC II microcalorimeter using a scanning method. The heptane solution shows a W-shaped C{sub pm}{sup E} concentration dependence, which reveals the existence of strong non-random effects. Systems including 1-alkanols are characterized by large and positive C{sub pm}{sup E} values. This remarks that self-association and/or solvation effects are predominant in such solutions. On the other hand, their C{sub pm}{sup E} curves are skewed towards higher mole fractions of the alcohol, which might be ascribed to the existence of more interactions between unlike molecules in that region.

  20. Dynamic and kinematic viscosities, excess volumes and excess Gibbs energies of activation for viscous flow in the ternary mixture {1- propanol+ N,N-dimethylformamide + chloroform} at temperatures between 293.15 K and 323.15 K

    Energy Technology Data Exchange (ETDEWEB)

    Hassein-bey-Larouci, A., E-mail: hasseinbey@yahoo.fr [Laboratoire Thermodynamique et Modélisation Moléculaire, Faculté de Chimie, Université des Sciences et de la Technologie Houari Boumediene, B.P. 32, El-Alia, 16111 Bab-Ezzouar, Alger (Algeria); Igoujilen, O.; Aitkaci, A. [Laboratoire Thermodynamique et Modélisation Moléculaire, Faculté de Chimie, Université des Sciences et de la Technologie Houari Boumediene, B.P. 32, El-Alia, 16111 Bab-Ezzouar, Alger (Algeria); Segovia, J.J.; Villamañán, M.A. [TERMOCAL Research Group, Escuela de Ingenierías Industriales, Universidad de Valladolid, Paseo del Cauce, 59, 47011 Valladolid (Spain)

    2014-08-10

    Highlights: • Many engineering applications require quantitative thermodynamic data of the fluids. • Excess properties of mixtures are important in the understanding of mixing process. • The results are used to explain the molecular interaction in the mixtures. - Abstract: Dynamic and kinematic viscosities, and densities of the ternary mixture {x_1 propanol + x_2 DMF + x_3 chloroform} and of the three corresponding binary systems have been measured at 293.15, 303.15, 313.15 and 323.15 K and atmospheric pressure. The thermophysical properties, viscosity deviations (Δη), kinematic viscosity (γ), excess Gibbs energies of activation of viscous flow (G*{sup E}) and excess molar volumes (V{sup E}) have been calculated from experimental values of dynamic viscosity, η, and density, ρ. The different results have been correlated by the Redlich–Kister equation for the binary mixtures and the Cibulka equation for equation for the ternary ones.

  1. Dynamic and kinematic viscosities, excess volumes and excess Gibbs energies of activation for viscous flow in the ternary mixture {1- propanol+ N,N-dimethylformamide + chloroform} at temperatures between 293.15 K and 323.15 K

    International Nuclear Information System (INIS)

    Highlights: • Many engineering applications require quantitative thermodynamic data of the fluids. • Excess properties of mixtures are important in the understanding of mixing process. • The results are used to explain the molecular interaction in the mixtures. - Abstract: Dynamic and kinematic viscosities, and densities of the ternary mixture {x1 propanol + x2 DMF + x3 chloroform} and of the three corresponding binary systems have been measured at 293.15, 303.15, 313.15 and 323.15 K and atmospheric pressure. The thermophysical properties, viscosity deviations (Δη), kinematic viscosity (γ), excess Gibbs energies of activation of viscous flow (G*E) and excess molar volumes (VE) have been calculated from experimental values of dynamic viscosity, η, and density, ρ. The different results have been correlated by the Redlich–Kister equation for the binary mixtures and the Cibulka equation for equation for the ternary ones

  2. 1-丙醇和2-丙醇真空紫外光电离质谱研究%A Vacu um Ultraviolet Photoionization Mass Spectrometric Study of 1-Propanol and 2-Propanol

    Institute of Scientific and Technical Information of China (English)

    卫立夏; 杨斌; 王晶; 黄超群; 盛六四; 齐飞

    2006-01-01

    The photoionization and dissociative photoionization of 1-propanol and 2-propanols have been studied at the photon energy range of 9.84~11.80 eV. Photoionization efficiency spectra for ions CH3CH2CH2OH+, CH3CH2CHOH+,CH2CH2OH+, CH3CH2CH2+, CH3CH=CH+2, CH2OH+ from 1-propanol, and CH3CH(OH)CH3+, CH3C(OH)CH3+, CH3CHOH+,CH2=CHOH+, CH3CHCH3+, CH3CH=CH2+ from 2-propanol have been measured. In addition, the energetics of the dissociative photoionization has been examined by ab initio Gaussion-3(G3) calculations. The computational results are useful in establishing the dissociation channels near the ionization thresholds. With the help of G3 results, the dissociation channels for formation of the fragment ions CH3CH2CHOH+, CH2CH2OH+, CH3CH2CH2+, CH3CH=CH2+,CH2OH+ from 1-propanol, and CH3C(OH)CH3+, CH3CHOH+, CH2=CHOH+, CH3CHCH3+, CH3CH=CH2+ from 2-propanol have been established. The G3 results are in excellent agreement with the experimental data.%研究了9.84~11.80 eV光子能量范围内1-丙醇和2-丙醇的光电离和离解光电离现象,测量了1-丙醇离解光电离产生的碎片离子CH3CH2CH2OH+、CH3CH2CHOH+、CH2CH2OH+、CH3CH2CH2+、CH3CH=CH2+和CH2OH+及2-丙醇离解光电离产生的碎片离子CH3CH(OH)CH3+、CH3C(OH)CH3+、CH3CHOH+、CH2=CHOH+、CH3CHCH3+和CH3CH=CH2+的光电离效率谱,得到了这些离子的出现势.结合从头算理论计算,给出了1-丙醇的碎片离子CH3CH2CHOH+、CH2CH2OH+、CH3CH2CH2+、CH3CH=CH2+、CH2OH+和2-丙醇的碎片离子CH3C(OH)CH3+、CH3CHOH+、CH2=CHOH+、CH3CHCH+3、CH3CH=CH2+等的解离通道和解离能.理论计算结果与实验结果符合得很好.

  3. 正丙醇和异丙醇对水溶液中牛血清白蛋白的构象及其荧光光谱的影响%Effects of 1-Propanol and 2-Propanol on the Conformation and Fluorescence Spectra of Bovine Serum Albumin in Aqueous Solutions

    Institute of Scientific and Technical Information of China (English)

    马林; 刘东群; 杨华; 童张法

    2008-01-01

      A combination of emission fluorescence spectroscopy (λex=280 nm,295 nm) and synchronous fluorescence spectroscopy (Δλ=15 nm、60 nm) with static light scattering measurement was used to investigate the effects of 1-propanol and 2-propanol on the conformation and fluorescence spectroscopy of Bovine Serum Albumin (BSA) in BSA-1-propanol-water and BSA-2-propanol-water systems. The results showed that 1-propanol and 2-propanol generally decreased, however at dilute solutions slightly increased, the stability of the structure of protein. And it was found that 1-propanol and 2-propanol were week protein denaturants, so that the fluorescence intensity of BSA was controlled by the mixing state of the mixtures at high 1-propanol and 2-propanol concentration.%  通过测定BSA-正丙醇-水和BSA-异丙醇-水体系中BSA的发射荧光(λex=280 nm、295 nm)和同步荧光(△λ=15 nm、60 nm),结合静态光散射技术,探索正丙醇和异丙醇对水溶液中蛋白质的构象和荧光光谱的影响。结果表明,正丙醇和异丙醇使蛋白质发生部分解折叠现象,但是,低浓度的正丙醇和异丙醇水溶液能轻微增强蛋白质的结构稳定性。总体上,正丙醇和异丙醇是弱的蛋白质变性剂,在浓度较高的体系中,体系的混合状态的变化对 BSA 的荧光强度的变化起主导作用。

  4. Spectroscopic investigations of new binuclear transition metal complexes of Schiff bases derived from 4,6-diacetylresorcinol and 3-amino-1-propanol or 1,3-diamino-propane

    Science.gov (United States)

    Emara, Adel A. A.; Saleh, Akila A.; Adly, Omima M. I.

    2007-11-01

    The bifunctional carbonyl compound; 4,6-diacetylresorcinol (DAR) serves as precursor for the formation of different Schiff base ligands, which are either di- or tetra-basic with two symmetrical sets of either O 2N or N 2O tridentate chelating sites. The condensation of 4,6-diacetylresorcinol with 3-amino-1-propanol (3-AP) or 1,3-diaminopropane (DAP), yields the corresponding hexadentate Schiff base ligands, abbreviated as H 4L a and H 2L b, respectively. The structures of these ligands were elucidated by elemental analyses, IR, mass, 1H NMR and electronic spectra. Reaction of the Schiff base ligands with copper(II), nickel(II), cobalt(II), zinc(II), cadmium(II), iron(III), chromium(III), vanadyl(IV) and uranyl(VI) ions in 1:2 molar ratio afforded the corresponding transition metal complexes. A variety of binuclear complexes for the metal complexes were obtained with the ligands in its di- or tetra-deprotonated forms. The structures of the newly prepared complexes were identified by elemental analyses, infrared, electronic, mass, 1H NMR and ESR spectra as well as magnetic susceptibility measurements and thermal gravimetric analysis (TGA). The bonding sites are the azomethine and amino nitrogen atoms, and phenolic and alcoholic oxygen atoms. The metal complexes exhibit different geometrical arrangements such as square planar, tetrahedral, square pyramid and octahedral arrangement.

  5. 双回流动态累积间歇精馏分离正丙醇-异丙醇物系过渡馏分的研究%Slop Cut in Separation of 1-Propanol from 2-Propanol by Dynamic-Accumulation Batch Distillation with Double-Reflux

    Institute of Scientific and Technical Information of China (English)

    陈立峰; 张兵; 李文秀; 于巍; 白鹏

    2011-01-01

    在双回流动态累积间歇精馏实验装置中,以正丙醇-异丙醇为物系进行了间歇精馏实验,考察了操作时间对过渡馏分采出段塔顶馏出液中正丙醇和异丙醇的含量及塔顶温度、塔釜液正丙醇含量及塔釜温度的影响.实验结果表明,原料中异丙醇质量分数别为30%,50%,70%时,对应的过渡馏分采出段操作时间分别为38,46,57 min;原料中异丙醇的含量越低,正丙醇回收率越高.在原料加入量为1L、加热功率为150 W、原料中异丙醇质量分数为30%的条件下,回收得到的正丙醇质量分数可达到86.66%,此时正丙醇的回收率为67.57%,过渡馏分的量最少,操作时间最短.%Batch distillation of 1 -propanol-2-propanol binary system was carried out in a set of dynamic-accumulation batch distillation apparatus with double- reflux. The effects of operation time on mass fractions of 1 -propanol and 2-propanol in the column top distillate, the column top temperature, mass fraction of 1 -propanol in the column bottoms and the column bottom temperature in the slop cut stage were investigated. The experimental results indicated that, when mass fraction of 2-propanol in the feed was 30% , 50% and 70% , the operation time of the corresponding slop cut stage was 38, 46 and 57 min. The 1-propanol yield increased while the mass fraction of 2-propanol in the feed decreased. Under the conditions of feed 1000 mL, heating power 150W and mass fraction of 2-propanol in the feed 30% , mass fraction of 1-propanol in the products was 86.66% and its yield was 67.57% , and the slop cut mass reached the minimum and the operation time of the slop cut stage was the shortest.

  6. 氯化钠-正丙醇-硫氰酸铵-水体系析相萃取分离和富集锡(Ⅳ)%Separation and enrichment of stannum (Ⅳ) by phase extraction in sodium chloride-1-propanol-ammonium thiocyanate-water system

    Institute of Scientific and Technical Information of China (English)

    李玉玲; 陈彬; 马万山

    2013-01-01

    The behavior and conditions for extraction separation and enrichment of stannum (Ⅳ) from other metal ions in sodium chloride-1-propanol-ammonium thiocyanate-water system were investigated.The results showed that 1-propanol aqueous solution could be well divided into two phases in presence of sodium chloride.During the phase separation process,[Sn(SCN)5~6] [(5~6)-4]-formed from stannum (Ⅳ) and ammonium thiocyanate could reacted with protonized 1-propanol of C3H7OH2 + to form associated complex of [Sn(SCN)5~6][C3 H7OH2]1-2,which could be fully extracted by 1-propanol phase.When acidity of the solution was fixed at pH 2.0,and the concentration of 1-propanol,ammonium thiocyanate and sodium chloride was 30%(V/V),0.09 mol/L and 0.17 g/mL,respectively,the extraction yield of stannum(Ⅳ) was more than 98.3%.Simultaneously,Fe(Ⅱ),Ni(Ⅱ),Pb(Ⅱ),Al (Ⅲ),Mg(Ⅱ),Mn(Ⅱ),Ce(Ⅲ),Cr(Ⅲ),Zn(Ⅱ),Ag(Ⅰ),Cd(Ⅱ)and V(V) could not be extracted,realizing the separation of stannum (Ⅳ) from these metal ions.The method has been applied to the separation and determination of stannum (Ⅳ) in Pb-Ca-Sn-Al alloy sample with recovery of 97.4% and relative standard deviation(n=7) of 2.1%.%研究了氯化钠-正丙醇-硫氰酸铵-水体系析相萃取分离和富集Sn(Ⅳ)的行为及与一些金属离子分离的条件.结果表明,氯化钠能使正丙醇的水溶液分成两相,在分相过程中,Sn(Ⅳ)和硫氰酸铵生成的[Sn(SCN)5~6][(5~6)-4]-与质子化正丙醇C3H7OH2+形成的缔合物[Sn (SCN)5~6][C3H7OH2]1-2能被正丙醇相完全萃取.固定溶液酸度为pH 2,当正丙醇、硫氰酸铵和氯化钠的浓度分别为30% (V/V)、0.09 mol/L和0.17 g/mL时,Sn(Ⅳ)的萃取率在98.3%以上,Fe(Ⅱ)、Ni(Ⅱ)、Pb(Ⅱ)、Al(Ⅲ)、Mg(Ⅱ)、Mn(Ⅱ)、Ce(Ⅲ)、Cr(Ⅲ)、Zn(Ⅱ)、Ag(Ⅰ)、Cd(Ⅱ)和V(Ⅴ)不被萃取,实现了Sn(Ⅳ)与上述金属离子的分离.方法用于Pb-Ca-Sn-Al合金中Sn的分离和测定,平均回收率为97.4

  7. 氯化钠-硫氰酸钾-正丙醇体系析相萃取分离和富集钛(Ⅳ)%Study on extraction and enrichment of titanium(Ⅳ) by phase separation with sodium chloride-potassium thiocyanate-1-propanol system

    Institute of Scientific and Technical Information of China (English)

    卢先春; 司学芝; 马冬冬; 许春萱

    2012-01-01

    研究了正丙醇-硫氰酸钾-水体系析相萃取分离和富集Ti(Ⅳ)的行为及与一些金属离子分离的条件.结果表明,氯化钠能使正丙醇的水溶液分成两相,在分相过程中,Ti(Ⅳ)和硫氢化钾生成的Ti(SCN)62-与质子化正丙醇C3 H7OH2+形成的缔合物[Ti(SCN)62-][C3 H7OH2+]2能被正丙醇相完全萃取.当正丙醇、硫氰酸钾和氯化钠的浓度分别为30%(V/V)、8.0×10-2 mol/L和0.17 g/mL时,Ti(Ⅳ)的萃取率达到98.9%以上,V(Ⅴ)、Ce(Ⅲ)、MgⅡ)、Mn(Ⅱ)、Cd(Ⅱ)、Cr(Ⅲ)、Al(Ⅲ)、Fe(Ⅱ)、Zn(Ⅱ)、Ni(Ⅱ)、Ag(Ⅰ)和W(Ⅵ)不被萃取,实现了Ti(Ⅳ)与上述金属离子的分离.对合成水样中的钛进行分离和测定,结果满意.%The enrichment and extraction behaviors of titanium(Ⅳ) in 1-propanol-potassium thiocyanate-aqueous system and the separation conditions from other metal ions were investigated. The results showed that the 1-propanol aqueous solution could be well divided into two phases in the presence of sodium chloride. The complex of [Ti(SCN)62- ][C3H7OH2+]2 formed from protonized 1-propanol ( [C3H7OH2 + ]2) and [Ti(SCN)62-] (which was generated by titanium (Ⅳ) and potassium thiocyanate) could be completely extracted by 1-propanol during the phase separation process. When the concentration of 1-propanol, potassium thiocyanate and sodium chloride was 30%(V/V) , 8. 0×10~2 mol/L and 0. 17 g/mL, respectively, the extraction yield of titaniumf(Ⅳ) was higher than 98. 9% while V(Ⅴ) Ce(Ⅲ), Mg(Ⅱ), Mn(Ⅱ), Cd(Ⅱ), Cr(Ⅲ), AI(Ⅲ), Fe(Ⅱ) , Zn(Ⅱ), Ni(Ⅱ), Ag(Ⅰ) and W(Ⅳ) were not extracted to realize the separation of titanium(Ⅳ) from the above-mentioned metal ions. This method has been successfully applied to the determination and extraction separation of titanium in the sample of synthetic water with satisfactory results.

  8. Henry's law constants and infinite dilution activity coefficients of cis-2-butene, dimethylether, chloroethane, and 1,1-difluoroethane in methanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutanol, tert-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, 3-methyl-1-butanol, and 2-methyl-2-butanol

    International Nuclear Information System (INIS)

    Henry's law constants and infinite dilution activity coefficients of cis-2-butene, dimethylether, chloroethane, and 1,1-difluoroethane in methanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutanol, tert-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, 3-methyl-1-butanol, and 2-methyl-2-butanol in the temperature range of 250 K to 330 K were measured by a gas stripping method and partial molar excess enthalpies were calculated from the activity coefficients. A rigorous formula for evaluating the Henry's law constants from the gas stripping measurements was used for the data reduction of these highly volatile mixtures. The uncertainty is about 2% for the Henry's law constants and 3% for the estimated infinite dilution activity coefficients. In the evaluation of the infinite dilution activity coefficients, the nonideality of the solute such as the fugacity coefficient and Poynting correction factor cannot be neglected, especially at higher temperatures. The estimated uncertainty of the infinite dilution activity coefficients includes 1% for nonideality

  9. Synthesis, in vitro and in vivo pharmacology of a C-11 labeled analog of CP-101,606, ({+-})threo-1-(4-hydroxyphenyl)-2-[4-hydroxy-4-(p-[{sup 11}C]methoxyphenyl) peridino]-1-propanol, as a PET tracer for NR2B subunit-containing NMDA receptors

    Energy Technology Data Exchange (ETDEWEB)

    Haradahira, Terushi E-mail: terushi@nirs.go.jp; Maeda, Jun; Okauchi, Takashi; Zhang, Ming-Rong; Hojo, Junko; Kida, Takayo; Arai, Takuya; Yamamoto, Fumihiko; Sasaki, Shigeki; Maeda, Minoru; Suzuki, Kazutoshi; Suhara, Tetsuya

    2002-07-01

    A carbon-11 labeled methoxyl analog of CP-101,606, ({+-})threo-1-(4-hydroxyphenyl)-2-[4-hydroxy-4-(p-[{sup 11}C]methoxyphenyl) piperidino]-1-propanol [({+-})[{sup 11}C]1], was synthesized as a new subtype-selective PET radioligand for NMDA receptors. The in vitro binding studies using rat brain slices demonstrated that ({+-})[{sup 11}C]1 shows an extremely high-specific binding to the NR2B subunit of NMDA receptors. In contrast to the in vitro binding, the in vivo binding to mouse and monkey brains showed no apparent specific localization of the radioactivity in any of the brain regions. Metabolism and physicochemical properties such as the lipophilicity of ({+-})[{sup 11}C]1 seemed unlikely to affect the in vivo ({+-})[{sup 11}C]1 binding. Among the various endogenous ligands acting at the NMDA receptors, polyamines (spermine and spermidine) and divalent cations (Mg{sup 2+,} Zn{sup 2+,} and Ca{sup 2+}) strongly inhibited the in vitro ({+-})[{sup 11}C]1 binding. Thus, the present studies point to the possibility that the polyamines and cations behave as endogenous inhibitors for ({+-})[{sup 11}C]1 binding, leading to the loss of the specific binding in vivo.

  10. [Bim]Ac离子液体+醇二元混合体系的体积和黏度性质研究%Volumetric and Viscosity Properties of 1-Butylimidazolium Acetate Ionic Liquid/Methanol, Ethanol or 1-Propanol Binary Mixtures

    Institute of Scientific and Technical Information of China (English)

    许映杰; 俞超红; 鲁越青

    2015-01-01

    1-Butylimidazolium acetate ([Bim]Ac) ionic liquid was synthesized, and the structure was characterized by1H-NMR,13C-NMR, and IR spectroscopy. Density and viscosity of [Bim]Ac+methanol, [Bim]Ac+ethanol, and [Bim]Ac+1-propanol binary mixtures were measured over an entire range of molar fraction at T=303.15 K under atmospheric pressure using a vibrating U-shaped sample tube densimeter and Ubbelohde Suspended-level viscometer, respectively. Excess molar volumes (VE), apparent molar volumes (Vfi), partial molar volumes (Vm,i), and excess partial molar volumes (VEm,i) of the studied systems were calculated with the density data. Viscosity deviations (Δη) of the studied systems were obtained from the viscosity data.VE andΔηwere fitted by Redlich-Kister equation, respectively. The results show that theVE values of the three studied systems are negative over the entire composition range, and a minimum value is reached with mole fraction of [Bim]Acx1=0.3~0.4. TheΔηvalues of the above-mentioned systems are also negative over the entire composition range, and a minimum value is reached withx1=0.4~0.5. TheVE orΔη values of the studied systems follow an order of [Bim]Ac+methanol < [Bim]Ac+ethanol < [Bim]Ac+1-propanol, which indicates that the interaction between [Bim]Ac and alkanol increases with the increase of alkanol polarity. TheVE andΔη values can be well fitted with Redlich-Kister equation.%合成了1-丁基咪唑醋酸盐([Bim]Ac)离子液体,通过1H-NMR、13C-NMR和IR对其结构进行了表征。在303.15 K和常压下,采用U形振荡管密度计测定了[Bim]Ac+甲醇、乙醇和正丙醇二元体系的密度,用乌氏黏度计测定了体系的黏度。由密度数据计算得到了体系的超额摩尔体积(VE)、表观摩尔体积(Vfi )、偏摩尔体积(V m,i )和超额偏摩尔体积( EV m,i ),由黏度数据获得了体系的混合黏度变化(∆h),并采用Redlich-Kister方程分别关联了VE、∆h与组成的关系。结果表明:

  11. Regeneration of 2-amino-2-methyl-1-propanol used for carbon dioxide absorption

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    To improve the efficiency of the carbon dioxide cycling process and to reduce the regeneration energy consumption, a sterically hindered amine of 2-amino-2-methyl-1- propranol (AMP) was investigated to determine its regeneration behavior as a CO2 absorbent. The CO2 absorption and amine regeneration characteristics were experimentally examined under various operating conditions. The regeneration efficiency increased from 86.2% to 98.3% during the temperature range of 358 K to 403 K. The most suitable regeneration temperature for AMP was 383 K, in this experiment condition, and the regeneration efficiency of absorption/regeneration runs descended from 98.3% to 94.0%. A number of heat-stable salts (HSS) could cause a reduction in CO2 absorption capacity and regeneration efficiency. The results indicated that aqueous AMP was easier to regenerate with less loss of absorption capacity than other amines, such as, monoethanolamine (MEA), diethanolamine (DEA), diethylenetriamine (DETA), and N-methyldiethanolamine (MDEA).

  12. Characterization of BF4− in terms of its effect on water by the 1-propanol probing methodology

    DEFF Research Database (Denmark)

    Morita, Takeshi; Ayako, Nitta; Nishikawa, Keilo;

    2014-01-01

    characterized as an amphiphile with weak hydrophobic and moderate hydrophilic contributions. These results were plotted on a two-dimensional map with hydrophobicity and hydrophilicity axes, H2O defining the origin. The melting point of 1-ethyl-3-methylimidazoliumtetrafluoroborate ([C2mim]BF4) was found within...... the trend that the larger the hydrophobicity and the hydrophilicity of the chosen counter anion, the lower the melting point of the resulting RTIL made of [C2mim]+ cation and the chosen anion. For the 1-butyl-3-methylimidazolium ([C4mim]+) based RTILs, however, redetermination of the melting point...

  13. Comparison of nitroethane, 2-nitro-1-propanol, lauric acid, Lauricidin and the Hawaiian marine algae, Chaetoceros, for potential broad-spectrum control of anaerobically grown lactic acid bacteria

    Science.gov (United States)

    The gastrointestinal tract of bovines often contains bacteria that contribute to disorders of the rumen and may also contain foodborne or opportunistic human pathogens as well as bacteria capable of causing mastitis in cows. Thus, there is a need to develop broad-spectrum therapies that are effecti...

  14. In vitro comparison of nitroethane, 2-nitro-1-propanol, lauric acid, Lauricidin(R), and the Hawaiian marine algae, Chaetoceros, activity against anaerobically grown Staphylococcus aureus

    Science.gov (United States)

    Mastitis is a common illness of dairy cattle and is very costly, economically, to the dairy farmer. Thus, there is a need to develop broad-spectrum therapies that are effective while not leading to unacceptably long antibiotic withdrawal times. The effects of the CH4-inhibitors nitroethane (2 mg/m...

  15. Interaction of some hydrophobic amino acids, peptides, and protein with aqueous 3-chloro-1,2-propanediol and 3-chloro-1-propanol: Biophysical studies

    Energy Technology Data Exchange (ETDEWEB)

    Keswani, Neelam [Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400 076 (India); Kishore, Nand, E-mail: nandk@chem.iitb.ac.i [Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400 076 (India)

    2011-04-15

    Research highlights: Thermodynamic properties of amino acids, peptides and protein determined in solution. The solvents chosen were 3-chloropropan-1-ol and 3-chloropropan-1,2-diol. {yields}The results enabled understanding the interactions quantitatively in these systems affecting the protein stability. Fine details of interactions provided in-depth analysis. - Abstract: The apparent molar volume V{sub 2,{phi},} apparent molar isentropic compressibility K{sub S,2,{phi},} and heat of dilution (q) of aqueous glycine, alanine, {alpha}-amino butyric acid, valine, leucine, diglycine, triglycine, and hen egg white lysozyme have been determined in aqueous solutions of 3-chloropropano-1-ol and 3-chloropropan-1,2-diol solutions at T = 298.15 K. These data have been used to calculate the infinite dilution standard partial molar volume V{sub 2,m}{sup 0}, partial molar isentropic compressibility K{sub S,2,m}{sup 0}, and enthalpy of dilution {Delta}{sub dil}H{sup o} of the amino acids and peptides in aqueous 3-chloropropano-1-ol and 3-chloropropan-1,2-diol, and the standard partial molar quantities of transfer of the amino acids and peptides to the aqueous alcohol and diol solutions. The linear correlation of V{sub 2,m}{sup 0} for a homologous series of amino acids has been utilized to calculate the contribution of the charged end groups (NH{sub 3}{sup +},COO{sup -}), CH{sub 2} group and other alkyl chains of the amino acids to the values of V{sub 2,m}{sup 0}. The results on the standard partial molar volumes of transfer, compressibility and enthalpy of dilution from water to aqueous alcohol and diol solutions have been correlated and interpreted in terms of ion-polar, ion-hydrophobic, and hydrophobic-hydrophobic group interactions. The heat of dilution of these amino acids, peptides, and hen egg white lysozyme measured in aqueous solutions of 3-chloropropano-1-ol and 3-chloropropan-1,2-diol by using isothermal titration calorimetry along with the volumetric, compressibility, and calorimetric results on amino acid and peptides have been correlated to understand the nature of interactions operating in these systems.

  16. Thermodynamic and acoustical properties of mixtures p-anisaldehyde—alkanols (C1-C4)—2-methyl-1-propanol at 303.15 K

    Science.gov (United States)

    Saini, Balwinder; Kumar, Ashwani; Rani, Ruby; Bamezai, Rajinder K.

    2016-07-01

    The density, viscosity and speed of sound of pure p-anisaldehyde and some alkanols, for example, methanol, ethanol, propan-1-ol, propan-2-ol, butan-1-ol, butan-2-ol, 2-methylpropan-1-ol, and the binary mixtures of p-anisaldehyde with these alkanols were measured over the entire composition range at 303.15 K. From the experimental data, various thermodynamic parameters such as excess molar volume ( V E), excess Gibbs free energy of activation (Δ G*E), and deviation parameters like viscosity (Δη), speed of sound (Δ u), isentropic compressibility (Δκs), are calculated. The excess as well as deviation parameters are fitted to Redlich—Kister equation. Additionally, the viscosity data for the systems has been used to correlate the application of empirical relation given by Grunberg and Nissan, Katti and Chaudhari, and Hind et al. The results are discussed in terms of specific interactions present in the mixtures.

  17. CO2 absorption into aqueous amine blended solutions containing monoethanolamine (MEA), N,N-dimethylethanolamine (DMEA), N,N-diethylethanolamine (DEEA) and 2-amino-2-methyl-1-propanol (AMP) for post-combustion capture processes

    NARCIS (Netherlands)

    Conway, William; Bruggink, Stefan; Beyad, Yaser; Luo, Weiliang; Melian-Cabrera, Ignacio; Puxty, Graeme; Feron, Paul

    2015-01-01

    Presently monoethanolamine (MEA) remains the industrial standard solvent for CO2 capture processes. Operating issues relating to corrosion and degradation of MEA at high temperatures and concentrations, and in the presence of oxygen, in a traditional PCC process, have introduced the requisite for hi

  18. 超临界正丙醇回收炭纤维增强环氧树脂复合材料%Recycling of carbon fibers in epoxy resin composites using supercritical 1-propanol

    Institute of Scientific and Technical Information of China (English)

    严华; 吕春祥; 经德齐; 常春报; 刘纳新; 侯相林

    2016-01-01

    研究了降解温度、反应时间和添加剂对超临界正丙醇中炭纤维增强环氧树脂基复合材料回收的影响.利用扫描电镜、热重、X射线光电子能谱、接触角和单丝拉伸对回收炭纤维进行表征.结果表明,随温度的升高,复合材料降解速率加快,但回收炭纤维力学性能略微降低.随反应时间的延长,复合材料降解速率降低,回收炭纤维力学性能降低.1%质量含量的KOH能明显提高复合材料的回收效率.伴随KOH含量增加,复合材料降解速率没有明显提高,而使回收炭纤维力学性能变差.合适的反应条件对回收具有清洁表面、良好热稳定性和力学性能完好保留的炭纤维至关重要.回收炭纤维表面化学的微弱变化使回收炭纤维同环氧树脂的接触角略增加.超临界正丙醇是一种回收炭纤维复合材料的有效方法.

  19. 4种高级氧化法处理高浓度正丙醇废水的动力学比较%Kinetic comparison on treatment of wastewater containing high concentration of 1-propanol with four types of advanced oxidation processes

    Institute of Scientific and Technical Information of China (English)

    曾惠明; 范蕊; 程慎玉; 沈晓莉; 徐天有; 金崇明

    2014-01-01

    研究了1%和10% (V/V)模拟正丙醇废水在UV/TiO2体系、UV/H2O2体系、Fe2+/H2O2体系和UV/TiO2/Fe2 +/H2O2体系等4种工艺条件下的降解动力学过程,对比了降解动力学特点及工艺参数对动力学常数的影响,优化工艺参数.结果表明,UV/TiO2体系和Fe2+/H2O2体系的降解过程可分为零级反应阶段和一级反应阶段,转折点分别在反应开始后2h和氧化剂浓度为6.7 g/L,UV/H2O2体系和UV/TiO2/Fe2+ /H2O2体系分别符合零级反应和一级反应规律;相同工艺参数条件下,6h反应后,组合工艺UV/TiO2/Fe2+/H2O2体系在处理效率达85%,比前3个体系分别高52.0%、8.3%和32.0%,与UV/TiO2体系和Fe2 +/H2O2体系的处理效率之和持平,其协同效应提高了速率常数,在目标物浓度降低时依然可维持较高降解速率.而目标物浓度提高10倍后,UV能量利用率提高35.5倍,氧化剂用量是Fe2+/H2O2体系的1/7.1.

  20. Studies of the behaviour of alcohols as co-surfactants in stabilizing microemulsions

    Energy Technology Data Exchange (ETDEWEB)

    Bahadur, P. (Chemistry Dept., D.A.V. (P.G.) Coll., Muzaffarnagar- (India)); Chand, M. (Chemistry Dept., D.A.V. (P.G.) Coll., Muzaffarnagar- (India))

    Micoremulsion formation was investigated in the following quaternary systems. Water/oil/surfactant/co-surfactant alcohol systems i.e. (i) water/xylene, benzene, toluene/tween-20/propanol-1, propanol-2, methanol, (ii) water/xylene, benzene, toluene/sodium dodecyl benzene sulphonate/propanol-1, propanol-2, methanol, (iii) water/xylene, benzene, toluene/dodecyl ammonium chloride/propanol-1, propanol-2, methanol. The formation of microemulsions is explained in terms of ternary phase diagrams for all three nonionic, anionic and cationic surfactants used. The viscosities and densities of the microemulsions were determined in all the systems. (orig.)

  1. Characterisation of tequila according to their major volatile composition using multilayer perceptron neural networks.

    Science.gov (United States)

    Ceballos-Magaña, Silvia G; de Pablos, Fernando; Jurado, José Marcos; Martín, María Jesús; Alcázar, Ángela; Muñiz-Valencia, Roberto; Gonzalo-Lumbreras, Raquel; Izquierdo-Hornillos, Roberto

    2013-02-15

    Differentiation of silver, gold, aged and extra-aged tequila using 1-propanol, ethyl acetate, 2-methyl-1-propanol, 3-methyl-1-butanol and 2-methyl-1-butanol and furan derivatives like 5-(hydroxymethyl)-2-furaldehyde and 2-furaldehyde has been carried out. The content of 1-propanol, ethyl acetate, 2-methyl-1-propanol, 3-methyl-1-butanol and 2-methyl-1-butanol was determined by means of head space solid phase microextraction gas chromatography mass-spectrometry. 5-(Hydroxymethyl)-2-furaldehyde and 2-furaldehyde were determined by high performance liquid chromatography with diode array detection. Kruskal-Wallis test was used to highlight significant differences between types of tequila. Principal component analysis was applied as visualisation technique. Linear discriminant analysis and multilayer perceptron artificial neural networks were used to construct classification models. The best classification performance was obtained when multilayer perceptron model was applied.

  2. Dissociation Constants and Thermodynamic Properties of Amines and Alkanolamines from (293 to 353) K

    NARCIS (Netherlands)

    Hamborg, Espen S.; Versteeg, Geert F.

    2009-01-01

    The dissociation constants of protonated 2-amino-2-ethyl-1,3-propanediol, 2-amino-2-methyl-1-propanol, diethylmonoethanolamine, diisopropanolamine, dimethylmonoethanolamine, monoethanolamine, 1-amino-2-propanol, methylmonoethanolamine, triethanolamine, and the first and the second dissociation const

  3. 1,2-Oxathiolane - A Photoelectron Spectroscopic Study

    DEFF Research Database (Denmark)

    Jørgensen, F. S.; Carlsen, Lars

    1983-01-01

    Der cyclische Sulfensureester 1,2-Oxathiolan (1) wurde durch milde Thermolyse von 3-(Phthalimidothio)-1-propanol (2) gewonnen und durch Photoelektronen-Spektroskopie identifiziert.- Die Möglichkeiten zur photoelektronenspektroskopischen Bestimmung der Konformation von Sulfensureestern werden...

  4. Characterization of volatile compounds of “Drenja”, an alcoholic beverage obtained from the fruits of cornelian cherry

    OpenAIRE

    VELE TEŠEVIĆ; NINOSLAV NIKIĆEVIĆ; SLOBODAN MILOSAVLJEVIĆ; DANICA BAJIĆ; VLATKA VAJS; IVAN VUČKOVIĆ; LJUBODRAG VUJISIĆ; IRIS ĐORĐEVIĆ; MIROSLAVA STANKOVIĆ; MILOVAN VELIČKOVIĆ

    2009-01-01

    In this study, volatile compounds were analyzed in five samples of home-made spirit beverage made by the distillation of fermented fruits of cornelian cherry (Cornus mas L.). The major volatile compounds, besides ethanol, identified and quantified were: methanol, acetaldehyde, 1-propanol, ethyl acetate, 2-methyl-1-propanol, 1-butanol, amyl alcohols, 1-hexanol and 2-phenylethanol. The minor volatiles were submitted to liquid–liquid extraction with dichloromethane and analyzed by gas chromatogr...

  5. Separation of eight selected flavan-3-ols on cellulose thin-layer chromatographic plates.

    Science.gov (United States)

    Vovk, Irena; Simonovska, Breda; Vuorela, Heikki

    2005-06-10

    The potential of microcristaline cellulose as sorbent in the separation of eight compounds: (+)-catechin (C), (-)-epicatechin (EC), (-)-gallocatechin (GC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECg), (-)-epigallocatechin gallate (EGCg), procyanidin B1 and procyanidin B2 was studied. Cellulose HPTLC plates prewashed in water (not necessary, when water was used as developing solvent) and dried with a hair dryer, bandwise application and development in horizontal developing chamber (sandwich configuration) gave the best results. Detection was performed using vanillin-H3PO4 reagent. Four new developing solvent systems were proposed: water, 1-propanol-water (20:80, v/v), 1-propanol-water-acetic acid (4:2:1, v/v) and 1-propanol-water-acetic acid (20:80:1, v/v), and at least two of them were needed for the differentiation between all eight compounds. Surprisingly, water enabled the separation of epimers C from EC and GC from EGC, as well as the dimers procianidin B1 and B2. Additionally, C, EGC, B1 and B2 were separated from all the other compounds. The best choice for developing solvent is given for each of the studied compounds. The best separation of the five main catechins (EC, GC, EGC, ECg, EGCg) present in green tea extract was achieved using 1-propanol-water-acetic acid (20:80:1, v/v). The chromatograms of oak bark extract developed in solvents with higher water content (1-propanol-water (1:4, v/v) and 1-propanol-water-acetic acid (20:80:1, v/v)) showed less bands than chromatograms developed in solvents with higher organic modifier content (e.g. 1-propanol-water-acetic acid (4:2:1, v/v)). It was proved that such behavior was due to the presence of procyanidins beside the main component catechin.

  6. Measurement and correlation of solubility of Tetracycline hydrochloride in six organic solvents

    International Nuclear Information System (INIS)

    Highlights: ► The solubility of Tetracycline hydrochloride (TCH) in six organic solvents was determined. ► Apelblat, NRTL and UNIQUAC models were used to correlate the experimental data. ► Superior correlation was achieved with NRTL model. - Abstract: The solubility of Tetracycline hydrochloride (TCH) in methanol, ethanol, 1-propanol, 1-butanol, acetone, and acetonitrile, was measured using a static method from (283.15 to 318.15) K. The solubility of TCH decreased in the order of methanol, ethanol, 1-propanol, 1-butanol, acetone, and acetonitrile. With increasing temperature, the solubility of TCH increased in ethanol, 1-propanol, 1-butanol, acetone, and acetonitrile but decreased in methanol. Moreover, the experimental solubility data were correlated by the modified Apelblat equation, NRTL and UNIQUAC models, respectively. And the calculated data by NRTL model showed better agreement with experimental values than the modified Apelblat equation and UNIQUAC model.

  7. A Simple Method for the Preparation of ZnO Prickly Spheres

    Institute of Scientific and Technical Information of China (English)

    Da Zhi LI; Xin Yu SONG; Si Xiu SUN; Jin Xin GUO

    2004-01-01

    The synthesis of ZnO prickly spheres using precipitation followed by heating treatment was investigated. Zn(OH)2 precursor was prepared by precipitation process using Zn(CH3COO)2·2H2O in mixed 1-propanol-water solvent. Sodium dodecyl sulfate (SDS) as the anionic surfactant was added to control the morphology. The size and structure of ZnO prickly spheres were studied using XRD, TEM and SEM. The results showed that the morphologies and size of the spheres strongly depended on the volume ratio of 1-propanol /water and molar ratio of SDS/Zn2+. ZnO prickly spheres composed of nanorods could be obtained, when the volume ratio of 1-propanol/water = 2:3 and the molar ratio of Zn2+/SDS ≈ 450:1.

  8. Debaryomyces hansenii strains differ in their production of flavor compounds in a cheese-surface model

    DEFF Research Database (Denmark)

    Gori, Klaus; Sørensen, Louise Marie; Petersen, Mikael Agerlin;

    2012-01-01

    important cheese flavor compounds, primarily branched-chain aldehydes and alcohols, and thus important for the final cheese flavor. Quantification of representative aldehydes (2-Methylpropanal, 3-Methylbutanal) and alcohols (2-Methyl-1-propanol, 3-Methyl-1-butanol, and 3-Methyl-3-buten-1-ol) showed...... that the investigated D. hansenii strains varied significantly with respect to production of these flavor compounds. Contrary to the alcohols (2-Methyl-1-propanol,3-Methyl-1-butanol, and3-Methyl-3-buten-1-ol), the aldehydes (2-Methylpropanal, 3-Methylbutanal) were produced by the D. hansenii strains in concentrations...

  9. Regioselective alkane hydroxylation with a mutant AlkB enzyme

    Science.gov (United States)

    Koch, Daniel J.; Arnold, Frances H.

    2012-11-13

    AlkB from Pseudomonas putida was engineered using in-vivo directed evolution to hydroxylate small chain alkanes. Mutant AlkB-BMO1 hydroxylates propane and butane at the terminal carbon at a rate greater than the wild-type to form 1-propanol and 1-butanol, respectively. Mutant AlkB-BMO2 similarly hydroxylates propane and butane at the terminal carbon at a rate greater than the wild-type to form 1-propanol and 1-butanol, respectively. These biocatalysts are highly active for small chain alkane substrates and their regioselectivity is retained in whole-cell biotransformations.

  10. The Mobile Phase Motion in Ascending Micellar Thin-Layer Chromatography with Normal-Phase Plates

    NARCIS (Netherlands)

    Boichenko, Alexander P.; Makhno, Iryna V.; Renkevich, Anton Yu.; Loginova, Lidia P.

    2011-01-01

    The physical chemical characteristics (surface tension and viscosity) of micellar mobile phases based on the cationic surfactant cetylpiridinium chloride and additives of alcohols (ethanol, 1-propanol, 1-butanol, 1-pentanol) have been obtained in this work. The effect of mobile phase properties on t

  11. GAS-LIQUID SOLUBILITIES OF CARBON-MONOXIDE, CARBON-DIOXIDE, HYDROGEN, WATER, 1-ALCOHOLS (1-LESS-THAN-OR-EQUAL-TO-N-LESS-THAN-OR-EQUAL-TO-6), AND N-PARAFFINS (2-LESS-THAN-OR-EQUAL-TO-N-LESS-THAN-OR-EQUAL-TO-6) IN HEXADECANE, OCTACOSANE, 1-HEXADECANOL, PHENANTHRENE, AND TETRAETHYLENE GLYCOL AT PRESSURES UP TO 5.5 MPA AND TEMPERATURES FROM 293 TO 553-K

    NARCIS (Netherlands)

    BREMAN, BB; BEENACKERS, AACM; RIETJENS, EWJ; STEGE, RJH

    1994-01-01

    The gas-liquid solubilities of the solutes carbon monoxide, carbon dioxide, hydrogen, water, ethane, propane, pentane, hexane, methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, and 1-hexanol in the solvents tetraethylene glycol, hexadecane, octacosane, 1-hexadecanol, and phenanthrene were measur

  12. Ruminal fermentation of anti-methanogenic nitro- and nitrate-containing forages in vitro

    Science.gov (United States)

    Nitrate, 3-nitro-1-propionic acid (NPA), and 3-nitro-1-propanol (NPOH) can accumulate in forages and be poisonous to animals if fed at high enough amounts. These chemicals are also recognized as potent anti-methanogenic compounds, but plants naturally containing these chemicals have been studied li...

  13. One pot direct synthesis of amides or oxazolines from carboxylic acids using Deoxo-Fluor reagent

    OpenAIRE

    Kangani, Cyrous O.; Kelley, David E.

    2005-01-01

    A mild and highly efficient one pot–one step condensation and/or condensation–cyclization of various acids to amides and/or oxazolines using Deoxo-Fluor reagents is described. Parallel syntheses of various free fatty acids with 2-amino-2, 2-dimethyl-1-propanol resulted with excellent yields.

  14. Catalyst Activity Comparison of Alcohols over Zeolites

    Energy Technology Data Exchange (ETDEWEB)

    Ramasamy, Karthikeyan K.; Wang, Yong

    2013-01-01

    Alcohol transformation to transportation fuel range hydrocarbon on HZSM-5 (SiO2 / Al2O3 = 30) catalyst was studied at 360oC and 300psig. Product distributions and catalyst life were compared using methanol, ethanol, 1-propanol or 1-butanol as a feed. The catalyst life for 1-propanol and 1-butanol was more than double compared to that for methanol and ethanol. For all the alcohols studied, the product distributions (classified to paraffin, olefin, napthene, aromatic and naphthalene compounds) varied with time on stream (TOS). At 24 hours TOS, liquid product from 1-propanol and 1-butanol transformation primarily contains higher olefin compounds. The alcohol transformation process to higher hydrocarbon involves a complex set of reaction pathways such as dehydration, oligomerization, dehydrocyclization, and hydrogenation. Compared to ethylene generated from methanol and ethanol, oligomerization of propylene and butylene has a lower activation energy and can readily take place on weaker acidic sites. On the other hand, dehydrocyclization of propylene and butylene to form the cyclic compounds requires the sits with stronger acid strength. Combination of the above mentioned reasons are the primary reasons for olefin rich product generated in the later stage of the time on stream and for the extended catalyst life time for 1 propanol and 1 butanol compared to methanol and ethanol conversion over HZSM-5.

  15. Mass balance evaluation of alcohol emission from cattle feed

    Science.gov (United States)

    Silage on dairy farms has been recognized as an important source of volatile organic compounds (VOCs) to the atmosphere, and therefore a contributor to tropospheric ozone. Considering reactivity and likely emission rates, ethanol, 1-propanol, and acetaldehyde probably make the largest contribution t...

  16. Selective Adsorption of Water from Mixtures with 1-Alcohols by Exploitation of Molecular Packing Effects in CuBTC

    NARCIS (Netherlands)

    J.J. Gutiérrez-Sevillano; S. Calero; R. Krishna

    2015-01-01

    The selective removal of water from mixtures with methanol, ethanol, and 1-propanol is an important task in the processing industries. With the aid of configurational-bias Monte Carlo simulations of unary and mixture adsorption, we establish the potential of CuBTC for this separation task. For opera

  17. Using Nuclear Magnetic Resonance Spectroscopy for Measuring Ternary Phase Diagrams

    Science.gov (United States)

    Woodworth, Jennifer K.; Terrance, Jacob C.; Hoffmann, Markus M.

    2006-01-01

    A laboratory experiment is presented for the upper-level undergraduate physical chemistry curriculum in which the ternary phase diagram of water, 1-propanol and n-heptane is measured using proton nuclear magnetic resonance (NMR) spectroscopy. The experiment builds upon basic concepts of NMR spectral analysis, typically taught in the undergraduate…

  18. AGONISTIC SENSORY EFFECTS OF AIRBORNE CHEMICALS IN MIXTURES: ODOR, NASAL PUNGENCY, AND EYE IRRITATION

    Science.gov (United States)

    Threshold responses of odor, nasal pungency (irritation), and eye irritation were measured for single chemicals (1-propanol, 1-hexanol, ethyl acetate, heptyl acetate, 2-pentanone, 2-heptanone, toluene, ethyl benzene, and propyl benzene) and mixtures of them (two three-component m...

  19. Aversive Olfactory Learning and Associative Long-Term Memory in "Caenorhabditis elegans"

    Science.gov (United States)

    Amano, Hisayuki; Maruyama, Ichiro N.

    2011-01-01

    The nematode "Caenorhabditis elegans" ("C. elegans") adult hermaphrodite has 302 invariant neurons and is suited for cellular and molecular studies on complex behaviors including learning and memory. Here, we have developed protocols for classical conditioning of worms with 1-propanol, as a conditioned stimulus (CS), and hydrochloride (HCl) (pH…

  20. Experimental validation of a rate-based model for CO2 capture using an AMP solution

    DEFF Research Database (Denmark)

    Gabrielsen, Jostein; Svendsen, H. F.; Michelsen, Michael Locht;

    2007-01-01

    Detailed experimental data, including temperature profiles over the absorber, for a carbon dioxide (CO"2) absorber with structured packing in an integrated laboratory pilot plant using an aqueous 2-amino-2-methyl-1-propanol (AMP) solution are presented. The experimental gas-liquid material balance...

  1. A Pseudomonas putida strain genetically engineered for 1,2,3-trichloropropane bioremediation

    NARCIS (Netherlands)

    Samin, Ghufrana; Pavlova, Martina; Arif, Muhammad; Postema, Christiaan P; Damborsky, Jiri; Janssen, Dick B

    2014-01-01

    1,2,3-Trichloropropane (TCP) is a toxic compound that is recalcitrant to biodegradation in the environment. Attempts to isolate TCP-degrading organisms using enrichment cultivation have failed. A potential biodegradation pathway starts with hydrolytic dehalogenation to 2,3-dichloro-1-propanol (DCP),

  2. Solid–liquid equilibria for binary and ternary systems with the Cubic-Plus-Association (CPA) equation of state

    DEFF Research Database (Denmark)

    Fettouhi, André; Thomsen, Kaj

    2010-01-01

    A systematic investigation of the CPA model's performance within solid-liquid equilibria (SLE) in binary mixtures (methane + ethane, methane + heptane, methane + benzene, methane + CO2, ethane + heptane, ethane + CO2, 1-propanol + 1,4-dioxane, ethanol + water, 2-propanol + water) is presented...

  3. Modeling of CO2 absorber using an AMP solution

    DEFF Research Database (Denmark)

    Gabrielsen, Jostein; Michelsen, Michael Locht; Stenby, Erling Halfdan;

    2006-01-01

    Abstract: An explicit model for carbon dioxide (CO2) solubility in an aqueous solution of 2-amino-2-methyl-1-propanol (AMP) has been proposed and an expression for the heat of absorption of CO2 has been developed as a function of loading and temperature. A rate-based steady-state model for CO2...

  4. Water-vapor-permeable Polyurethane Ionomer

    Institute of Scientific and Technical Information of China (English)

    LIOU Y.J.; Chao D. Y.

    2005-01-01

    @@ 1Introduction The reaction of toluene diisocyanate with 2,2,3,3-tetrafluoro-1-propanol (fluoro compound) or 3-glycidoxypropyl trimethoxysilane (siloxane compound) and other additives to form the structure of the fluoro-based or siloxane-based polyurethane (PU) ionomer has been proven by infrared spectra.

  5. Reduction of 2-chloro-N-phenylpropanamide and 2-methyl-N-phenylaziridine with lithium aluminium hydride

    DEFF Research Database (Denmark)

    Vilhelmsen, Mie Højer; Østergaard, Lars Frøsig; Nielsen, Mogens Brøndsted;

    2008-01-01

    -chloropropanamide, which indicates that Lewis acid catalysis (by aluminium chlorohydrides) facilitates the reduction of the aziridine. In addition, Lewis acid catalysis increases the relative yield of the propylamine product. The reduction of 2-chloro-N-phenylpropanamide furnishes 2-phenylamino-1-propanol as a by......-product, rather than the previously proposed 1-phenylamino-2-propanol....

  6. Measurements and modeling of VLLE at elevated pressures

    DEFF Research Database (Denmark)

    Laursen, Torben

    and pure component calibration. Samples from the different liquid phases in the high-pressure cell is taken using a moveable needle. The systems investigated have been a combination of the components: CO2, N2, di-methyl ether (DME), water, methanol, ethanol and 1-propanol. 41 isotherms have been measured...

  7. How Much Weaker Are the Effects of Cations than Those of Anions?

    DEFF Research Database (Denmark)

    Morita, Takeshi; Westh, Peter; Nishikawa, Keilo;

    2014-01-01

    We characterized the effects of K+ and Cs+ ions on the molecular organization of H2O by the 1-propanol probing methodology, previously developed by us (Phys. Chem. Chem. Phys. 2013, 15, 14548). The results indicated that both ions belong to the class of “hydration center”, which is hydrated by 4...

  8. Correlation for fitting multicomponent vapor-liquid equilibria data and prediction of azeotropic behavior

    Directory of Open Access Journals (Sweden)

    Khalid Farhod Chasib Al-Jiboury

    2007-01-01

    Full Text Available Correlation equations for expressing the boiling temperature as direct function of liquid composition have been tested successfully and applied for predicting azeotropic behavior of multicomponent mixtures and the kind of azeotrope (minimum, maximum and saddle type using modified correlation of Gibbs-Konovalov theorem. Also, the binary and ternary azeotropic point have been detected experimentally using graphical determination on the basis of experimental binary and ternary vapor-liquid equilibrium data.In this study, isobaric vapor-liquid equilibrium for two ternary systems: “1-Propanol – Hexane – Benzene” and its binaries “1-Propanol – Hexane, Hexane – Benzene and 1-Propanol – Benzene” and the other ternary system is “Toluene – Cyclohexane – iso-Octane (2,2,4-Trimethyl-Pentane” and its binaries “Toluene – Cyclohexane, Cyclohexane – iso-Octane and Toluene – iso-Octane” have been measured at 101.325 KPa. The measurements were made in recirculating equilibrium still with circulation of both the vapor and liquid phases. The ternary system “1-Propanol – Hexane – Benzene” which contains polar compound (1-Propanol and the two binary systems “1-Propanol – Hexane and 1-Propanol – Benzene” form a minimum azeotrope, the other ternary system and the other binary systems do not form azeotrope.All the data passed successfully the test for thermodynamic consistency using McDermott-Ellis test method (McDermott and Ellis, 1965.The maximum likelihood principle is developed for the determination of correlations parameters from binary and ternary vapor-liquid experimental data which provides a mathematical and computational guarantee of global optimality in parameters estimation for the case where all the measured variables are subject to errors and the non ideality of both vapor and liquid phases for the experimental data for the ternary and binary systems have been accounted.The agreement between prediction and experimental data is

  9. Influência do dióxido de enxofre e cultivares de videira na formação de alguns compostos voláteis e na qualidade sensorial do destilado de vinho Influence of sulfur dioxide and grape varieties at the formation of some volatile compounds and at the sensory quality of the wine distillate

    Directory of Open Access Journals (Sweden)

    Marco Antonio SALTON

    2000-12-01

    Full Text Available Com o objetivo de estudar o efeito do SO2 e das cultivares de videira - Herbemont, Couderc 13, Trebbiano e Isabel - na composição química e na qualidade sensorial do destilado de vinho, efetuaram-se microvinificações e posterior destilação dos vinhos na safra de 1996. As análises dos compostos voláteis foram feitas através de cromatografia gasosa e a avaliação sensorial dos destilados foi efetuada pelo grupo de degustação da Embrapa Uva e Vinho. Os resultados mostraram que o SO2 favoreceu a formação de etanal nas cultivares estudadas. Observou-se também um aumento na soma dos álcoois superiores em função do SO2, exceto para o destilado da cv. Isabel. Constatou-se que o destilado de Isabel se caracterizou por apresentar teor mais elevado de metanol e mais baixo de 1-propanol, possivelmente devido ao sistema de vinificação. O destilado de Isabel, juntamente com o de Couderc 13, apresentou teores mais baixos de 2-metil-1-propanol, 3-metil-1-butanol e da soma dos álcoois superiores. O destilado de Trebbiano apresentou teor mais elevado de 2-metil-1-propanol e juntamente com o de Herbemont teores mais elevados de 1-propanol, 2-metil-1-butanol, 3-metil-1-butanol e na soma dos álcoois superiores. A avaliação sensorial evidenciou que o SO2 influenciou na qualidade de aroma, no gosto agradável e na qualidade geral dos destilados das cultivares Herbemont e Trebbiano. O de Herbemont se caracterizou por apresentar menor qualidade de aroma, gosto agradável, tipicidade e qualidade geral. Apresentou, ainda, nota mais elevada para aroma e gosto indesejáveis.With the aim of studying the influence of SO2 and grape varieties - Herbemont, Couderc 13, Trebbiano and Isabella, on the chemical composition and sensory quality of wine distillates, some microvinification and posterior distillation of wines were made, at the harvest of 1996. The analyses of volatile components were made through gas chromatography and the sensory evaluation of

  10. Selective deoxygenation of aldehydes and alcohols on molybdenum carbide (Mo2C) surfaces

    Science.gov (United States)

    Xiong, Ke; Yu, Weiting; Chen, Jingguang G.

    2014-12-01

    The selective deoxygenation of aldehydes and alcohols without cleaving the Csbnd C bond is crucial for upgrading bio-oil and other biomass-derived molecules to useful fuels and chemicals. In this work, propanal, 1-propanol, furfural and furfuryl alcohol were selected as probe molecules to study the deoxygenation of aldehydes and alcohols on molybdenum carbide (Mo2C) prepared over a Mo(1 1 0) surface. The reaction pathways were investigated using temperature programmed desorption (TPD) and high resolution electron energy loss spectroscopy (HREELS). The deoxygenation of propanal and 1-propanol went through a similar intermediate (propoxide or η2(C,O)-propanal) to produce propene. The deoxygenation of furfural and furfuryl alcohol produced a surface intermediate similar to adsorbed 2-methylfuran. The comparison of these results revealed the promising deoxygenation performance of Mo2C, as well as the effect of the furan ring on the selective deoxygenation of the Cdbnd O and Csbnd OH bonds.

  11. Significance of volatile compounds produced by spoilage bacteria in vacuum-packed cold-smoked salmon ( Salmo salar ) analyzed by GC-MS and multivariate regression

    DEFF Research Database (Denmark)

    Jørgensen, Lasse Vigel; Huss, Hans Henrik; Dalgaard, Paw

    2001-01-01

    Changes were studied in the concentration of 38 volatile compounds during chilled storage at 5 degreesC of six lots of commercially produced vacuum-packed cold-smoked salmon and sterile cold-smoked salmon. The majority of volatile compounds produced during spoilage of cold-smoked salmon were alco...... alcohols, which were produced by microbial activity. Partial least- squares regression of volatile compounds and sensory results allowed for a multiple compound quality index to be developed. This index was based on volatile bacterial metabolites, 1- propanol and 2-butanone, and 2-furan......, 1- penten-3-ol, and 1-propanol. The potency and importance of these compounds was confirmed by gas chromatography- olfactometry. The present study provides valuable information on the bacterial reactions responsible for spoilage off-flavors of cold-smoked salmon, which can be used to develop...

  12. Effect of tungstate on acetate and ethanol production by the electrosynthetic bacterium Sporomusa ovata

    DEFF Research Database (Denmark)

    Ammam, Fariza; Tremblay, Pier-Luc; Lizak, Dawid Mariusz;

    2016-01-01

    resulted in a 2.9-fold increase in ethanol production by S. ovata during H2:CO2-dependent growth. It also promoted electrosynthesis of ethanol in a S. ovata-driven MES reactor and increased acetate production 4.4-fold compared to unmodified medium. Furthermore, fatty acids propionate and butyrate were...... successfully converted to their corresponding alcohols 1-propanol and 1-butanol by S. ovata during gas fermentation. Increasing tungstate concentration enhanced conversion efficiency for both propionate and butyrate. Gene expression analysis suggested that tungsten-containing aldehyde ferredoxin...... oxidoreductases (AORs) and a tungsten-containing formate dehydrogenase (FDH) were involved in the improved biosynthesis of acetate, ethanol, 1-propanol, and 1-butanol. AORs and FDH contribute to the fatty acids re-assimilation pathway and the Wood-Ljungdahl pathway, respectively. This study presented here shows...

  13. Measurement and modeling of high-pressure (vapour + liquid) equilibria of (CO2 + alcohol) binary systems

    International Nuclear Information System (INIS)

    An apparatus based on a static-analytic method assembled in this work was utilized to perform high pressure (vapour + liquid) equilibria measurements with uncertainties estimated at 2 + 1-propanol), (CO2 + 2-methyl-1-propanol), (CO2 + 3-methyl-1-butanol), and (CO2 + 1-pentanol) binary systems at temperatures of (313, 323, and 333) K, and at pressure range of (2 to 12) MPa. For all the (CO2 + alcohol) systems, it was visually monitored to insure that there was no liquid immiscibility at the temperatures and pressures studied. The experimental results were correlated with the Peng-Robinson equation of state using the quadratic mixing rules of van der Waals with two adjustable parameters. The calculated (vapour + liquid) equilibria compositions were found to be in good agreement with the experimental values with deviations for the mol fractions <0.12 and <0.05 for the liquid and vapour phase, respectively.

  14. Alcohol and water adsorption in zeolitic imidazolate frameworks

    KAUST Repository

    Zhang, Ke

    2013-01-01

    Alcohol (methanol, ethanol, 1-propanol, 2-propanol and 1-butanol) and water vapor adsorption in zeolitic imidazolate frameworks (ZIF-8, ZIF-71 and ZIF-90) with similar crystal sizes was systematically studied. The feasibility of applying these ZIF materials to the recovery of bio-alcohols is evaluated by estimating the vapor-phase alcohol-water sorption selectivity. © 2013 The Royal Society of Chemistry.

  15. Intermolecular Interactions in Ternary Glycerol–Sample–H2O

    DEFF Research Database (Denmark)

    Westh, Peter; Rasmussen, Erik Lumby; Koga, Yoshikata

    2011-01-01

    -butanol (TBA), 1-propanol (1P), urea (UR), NaF, NaCl, NaBr, NaI, and NaSCN were used. It was found that hydrophobes (TBA and 1P) reduce the values of HGly-GlyEHEGly--Gly considerably, but a hydrophile (UR) had very little effect on HGly-GlyEHEGly--Gly. The results with Na salts indicated that there have very...

  16. Synthesis of Non-Cytotoxic Poly(Ester-Amine) Dendrimers as Potential Solubility Enhancers for Drugs: Methotrexate as a Case Study

    OpenAIRE

    Patricia Guadarrama; María Teresa Ramírez Apan; Jorge A. Cruz-Morales; Delia Soto-Castro

    2010-01-01

    This study describes the synthesis of two new families of dendrimers based on the esterification of N-alkylated 3-amine-1-propanol with two different cores, adipic acid (1st and 2nd generations) and ethylenediamine (generation 1.5), both with carboxylic acid end groups, offering a wide variety of further modifications at the periphery. According to the cytotoxic evaluation of the dendrimers and their possible degradation products within cell lines, these materials could be considered as innoc...

  17. Metabolic Engineering of Microorganisms for the Production of Higher Alcohols

    OpenAIRE

    Choi, Yong Jun; Lee, Joungmin; Jang, Yu-Sin; Lee, Sang Yup

    2014-01-01

    ABSTRACT Due to the increasing concerns about limited fossil resources and environmental problems, there has been much interest in developing biofuels from renewable biomass. Ethanol is currently used as a major biofuel, as it can be easily produced by existing fermentation technology, but it is not the best biofuel due to its low energy density, high vapor pressure, hygroscopy, and incompatibility with current infrastructure. Higher alcohols, including 1-propanol, 1-butanol, isobutanol, 2-me...

  18. Sequential polymerization of ethylene oxide, ε-caprolactone and l-lactide: A one-pot metal-free route to tri- and pentablock terpolymers

    KAUST Repository

    Zhao, Junpeng

    2014-01-01

    Metal-free polymerization of ethylene oxide (EO) catalyzed by a relatively mild phosphazene base (t-BuP2) was proven feasible, which enabled the one-pot sequential polymerization of EO, ε-caprolactone, and l-lactide. Using either 3-phenyl-1-propanol or water as an initiator, the corresponding triblock or pentablock terpolymers were easily prepared. © 2014 the Partner Organisations.

  19. Experimental study of thermodynamic and transport properties of binary mixtures of poly(ethylene glycol) diacrylate and alcohols at different temperatures

    OpenAIRE

    Vuksanović Jelena M.; Radović Ivona R.; Šerbanović Slobodan P.; Kijevčanin Mirjana Lj.

    2015-01-01

    Experimental density r, refractive index nD and viscosity h data of three binary systems of poly(ethylene glycol) diacrylate (PEGDA) + ethanol, + 1-propanol, and + 1-butanol were measured at eight temperatures from (288.15 to 323.15) K, with temperature step of 5 K, and at atmospheric pressure. The experimental data were correlated as a function of PEGDA mole fraction and temperature. Densities and refractive indices of the investigated mixtures could be fi...

  20. Enzymatic resolution of (R,S)-ibuprofen and (R,S)-ketoprofen by microbial lipases from native and commercial sources Resolução enzimática do (R,S)-ibuprofeno e (R,S)-cetoprofeno por lipases microbianas de fontes nativas e comerciais

    OpenAIRE

    Patrícia de Oliveira Carvalho; Fabiano Jares Contesini; Masaharu Ikegaki

    2006-01-01

    The enantioselectivity (E) of native lipases from Aspergillus niger, Aspergillus terreus, Fusarium oxysporum, Mucor javanicus, Penicillium solitum and Rhizopus javanicus in the resolution of (R,S)-ibuprofen and (R,S)-ketoprofenenantiomers by esterification reaction with 1-propanol in isooctane was compared with known commercial Candida rugosa (Sigma) and Candida antarctica (Novozym®435) lipases. In the resolution of (R,S)-ibuprofen, C. rugosa lipase showed good selectivity (E = 12) while Novo...

  1. Systematic study of the thermal diffusion in associated mixtures

    OpenAIRE

    Polyakov, P.; Wiegand, S.

    2008-01-01

    We performed systematic temperature and concentration dependent measurements of the Soret coefficient in different associated binary mixtures of water, deuterated water, dimethyl sulfoxide (DMSO), methanol, ethanol, acetone, methanol, 1-propanol, 2-propanol, and propionaldehyde using the so-called thermal diffusion forced Rayleigh scattering method. For some of the associating binary mixtures such as ethanol/water, acetone/water, and DMSO/water, the concentration xw+/- at which the Soret coef...

  2. (Vapor + liquid) equilibria of the binary mixtures of m-cresol with C1-C4 aliphatic alcohols at 95.5 kPa

    International Nuclear Information System (INIS)

    Bubble point temperatures at 95.5 kPa, over the entire composition range, are measured for the binary mixtures formed by m-cresol with: methanol, ethanol, 1-propanol, 2-propanol, and n-, iso-, sec-, and tert-butanols - using a Swietoslawski-type ebulliometer. The liquid phase composition - bubble point temperature measurements are well represented by the Wilson model. (Vapor + liquid) equilibria predicted from the model are presented

  3. Characterization of Volatile Components in Makgeolli, a Traditional Korean Rice Wine, with or without Pasteurization, During Storage

    OpenAIRE

    Sang Hoon Song; Young-Suk Kim; Sang Mi Lee; Hye-Jung Park

    2013-01-01

    Changes in the volatile components of unpasteurized and pasteurized makgeolli during 30 days of storage were investigated by gas chromatography-mass spectrometry (GC-MS) and GC-olfactometry (GC-O). A total of 11 odor-active compounds such as 3-methyl-1-butanol (isoamyl alcohol), 2-methyl-1-butanol, 2,3-butanediol, butanoic acid, 3-methylbutanoic acid (isovaleric acid), 2-methylbutanoic acid, 3-(methylthio)-1-propanol (methionol), 2-phenylethanol, ethyl decanoate, ethyl dodecanoate, and ethyl ...

  4. Fiber content of diet affects exhaled breath volatiles in fasting and postprandial state in a pilot crossover study.

    Science.gov (United States)

    Raninen, Kaisa J; Lappi, Jenni E; Mukkala, Maria L; Tuomainen, Tomi-Pekka; Mykkänen, Hannu M; Poutanen, Kaisa S; Raatikainen, Olavi J

    2016-06-01

    Our pilot study examined the potential of exhaled breath analysis in studying the metabolic effects of dietary fiber (DF). We hypothesized that a high-fiber diet (HFD) containing whole grain rye changes volatile organic compound (VOC) levels in exhaled breath and that consuming a single meal affects these levels. Seven healthy men followed a week-long low-fiber diet (17 g/d) and HFD (44 g/d) in a randomized crossover design. A test meal containing 50 g of the available carbohydrates from wheat bread was served as breakfast after each week. Alveolar exhaled breath samples were analyzed at fasting state and 30, 60, and 120 minutes after this meal parallel to plasma glucose, insulin, and serum lipids. We used solid-phase microextraction and gas chromatography-mass spectrometry for detecting changes in 15 VOCs. These VOCs were acetone, ethanol, 1-propanol, 2-propanol, 1-butanol, acetic acid, propionic acid, butyric acid, valeric acid, isovaleric acid, 2-methylbutyric acid, hexanoic acid, acetoin, diacetyl, and phenol. Exhaled breath 2-methylbutyric acid in the fasting state and 1-propanol at 120 minutes decreased (P = .091 for both) after an HFD. Ingestion of the test meal increased ethanol, 1-propanol, acetoin, propionic acid, and butyric acid levels while reducing acetone, 1-butanol, diacetyl, and phenol levels. Both DF diet content and having a single meal affected breathVOCs. Exploring exhaled breath further could help to develop tools for monitoring the metabolic effects of DF. PMID:27188907

  5. Modelling of volumetric properties of binary and ternary mixtures by CEOS, CEOS/GE and empirical models

    Directory of Open Access Journals (Sweden)

    BOJAN D. DJORDJEVIC

    2007-12-01

    Full Text Available Although many cubic equations of state coupled with van der Waals-one fluid mixing rules including temperature dependent interaction parameters are sufficient for representing phase equilibria and excess properties (excess molar enthalpy HE, excess molar volume VE, etc., difficulties appear in the correlation and prediction of thermodynamic properties of complex mixtures at various temperature and pressure ranges. Great progress has been made by a new approach based on CEOS/GE models. This paper reviews the last six-year of progress achieved in modelling of the volumetric properties for complex binary and ternary systems of non-electrolytes by the CEOS and CEOS/GE approaches. In addition, the vdW1 and TCBT models were used to estimate the excess molar volume VE of ternary systems methanol + chloroform + benzene and 1-propanol + chloroform + benzene, as well as the corresponding binaries methanol + chloroform, chloroform + benzene, 1-propanol + chloroform and 1-propanol + benzene at 288.15–313.15 K and atmospheric pressure. Also, prediction of VE for both ternaries by empirical models (Radojković, Kohler, Jackob–Fitzner, Colinet, Tsao–Smith, Toop, Scatchard, Rastogi was performed.

  6. Selective deoxygenation of aldehydes and alcohols on molybdenum carbide (Mo{sub 2}C) surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Ke [Catalysis Center for Energy Innovation, Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19716 (United States); Yu, Weiting [Chemical Engineering, Columbia University, New York, NY 10027 (United States); Chen, Jingguang G., E-mail: jgchen@columbia.edu [Chemical Engineering, Columbia University, New York, NY 10027 (United States)

    2014-12-30

    Highlights: • Mo{sub 2}C surface can deoxygenate propanal and 1-propanol to produce propene through a similar intermediate (propoxide or η{sup 2}(C,O)-propanal). • Mo{sub 2}C surface can deoxygenate furfural and furfuryl alcohol to make 2-methylfuran through a 2-methylfuran-like intermediate. • The presence of furan ring modifies the selectivity between deoxygenation and hydrogenation/dehydrogenation pathways. - Abstract: The selective deoxygenation of aldehydes and alcohols without cleaving the C-C bond is crucial for upgrading bio-oil and other biomass-derived molecules to useful fuels and chemicals. In this work, propanal, 1-propanol, furfural and furfuryl alcohol were selected as probe molecules to study the deoxygenation of aldehydes and alcohols on molybdenum carbide (Mo{sub 2}C) prepared over a Mo(1 1 0) surface. The reaction pathways were investigated using temperature programmed desorption (TPD) and high resolution electron energy loss spectroscopy (HREELS). The deoxygenation of propanal and 1-propanol went through a similar intermediate (propoxide or η{sup 2}(C,O)-propanal) to produce propene. The deoxygenation of furfural and furfuryl alcohol produced a surface intermediate similar to adsorbed 2-methylfuran. The comparison of these results revealed the promising deoxygenation performance of Mo{sub 2}C, as well as the effect of the furan ring on the selective deoxygenation of the C=O and C-OH bonds.

  7. 双回流动态累积间歇精馏全过程的研究%Study on dynamic-accumulation batch distillation of a noveloperation tower with double-reflux

    Institute of Scientific and Technical Information of China (English)

    张兵; 陈立峰; 李文秀

    2011-01-01

    在动态累积间歇精馏塔中,采用双回流动态累积间歇精馏操作对正丙醇-异丙醇二元混合物系进行分离研究.主要考察了操作时间对塔顶整个过程产品浓度、温度变化的影响,并与塔顶回流动态累积间歇精馏操作的分离结果进行了比较,以及过渡馏分阶段操作时间对塔釜正丙醇浓度及温度变化的影响,同时,又对正丙醇的回收进行了研究.结果表明,在同样的产品采出要求条件下,双回流动态累积间歇精馏操作时,随原料中异丙醇含量的增加,所需的操作时间越长,产品的纯度越高,收率越高;操作时间节省166 min,原料中异丙醇质量分数为30%的条件下,所得回收正丙醇的纯度达到91.22%,正丙醇的回收率可达62.93%,原料中异丙醇质量分数别为30%、50%、70%时对应过渡馏分持续时间分别为40、47、58m in;原料中异丙醇质量分数越大,所得回收正丙醇产品的量越少,正丙醇的纯度越低,回收率越小.%A novel double-reflux operation mode by reflux at both top and bottom was applied in a dynamic-accumulation batch distillation tower. Binary mixture of 1-propanol and 2-propanol as the separated system,in the state progress the mass fraction change of 2-propanol and temperature with operation time at top was studied, while the effection was compared with the operation by reflux at top;during slop cut stage the mass fraction change of 1-propanol and temperature at bottom with operation time were mainly discussed. The recovery of 1-propanol was mainly considered. The experiment results indicate that the operation time, mass fraction of 2-propanol in product and yield of 2-propanol all increase with the mass fraction of 2-propanol added more in feed at the same condition of product quality. When mass fraction of 2-propanol in feed was 30% ,the mass fraction of 1-propanol in product was 91. 22% and yield of 1-propanol was 62. 93% . When mass fraction of 2-propanol

  8. The use of coenzyme Q0 as a template in the development of a molecularly imprinted polymer for the selective recognition of coenzyme Q10.

    Science.gov (United States)

    Contin, Mario; Flor, Sabrina; Martinefski, Manuela; Lucangioli, Silvia; Tripodi, Valeria

    2014-01-01

    In this work, a novel molecularly imprinted polymer (MIP) for use as a solid phase extraction sorbent was developed for the determination of coenzyme Q10 (CoQ10) in liver extract. CoQ10 is an essential cofactor in mitochondrial oxidative phosphorylation and a powerful antioxidant agent found in low concentrations in biological samples. This fact and its high hydrophobicity make the analysis of CoQ10 technically challenging. Accordingly, a MIP was synthesised using coenzyme Q0 as the template, methacrylic acid as the functional monomer, acetonitrile as the porogen, ethylene glycol dimethacrylate as the crosslinker and benzoyl peroxide as the initiator. Various parameters affecting the polymer preparation and extraction efficiency were evaluated. Morphological characterisation of the MIP and its proper comparison with C18 as a sorbent in solid phase extraction were performed. The optimal conditions for the molecularly imprinted solid phase extraction (MISPE) consisted of 400 μL of sample mixed with 30 mg of MIP and 600 μL of water to reach the optimum solution loading. The loading was followed by a washing step consisting of 1 mL of a 1-propanol solution (1-propanol:water, 30:70,v/v) and elution with 1 mL of 1-propanol. After clean-up, the CoQ10 in the samples was analysed by high performance liquid chromatography. The extraction recoveries were higher than 73.7% with good precision (3.6-8.3%). The limits of detection and quantification were 2.4 and 7.5 μg g(-1), respectively, and a linear range between 7.5 and 150 μg g(-1) of tissue was achieved. The new MISPE procedure provided a successful clean-up for the determination of CoQ10 in a complex matrix.

  9. Characteristic of Nitron for Use as a Chemical Sensor in Studies of the Upper Atmosphere

    Science.gov (United States)

    Meadows, Kapres; Wright, Cassandra K.; Sims, S. C.; Morris, V. R.

    1997-01-01

    We are investigating the use of nitron as a potential chemical sensor for nitric acid and other electron deficient nitrogen oxides. Solutions of nitron in 1-propanol, toluene, and chloroform have been tested for use on a piezoelectric quartz crystal microbalance. We are testing various solvents and metal cations which can maximize the lifetime and reaction specificity of nitron so that they may be used as chemical coatings for stratospheric measurement of trace gases. Results of the work to date will be shown, and future direction discussed.

  10. Total synthesis of (-)- and (+)-tedanalactam

    Digital Repository Service at National Institute of Oceanography (India)

    Majik, M.S.; Parameswaran, P.S.; Tilve, S.G.

    are given in Hz. Chiral HPLC analyses was executed using Jasco HPLC model MX-2080-31 instrument. tert-Butyl (3-hydroxypropyl)carbamate (10): The Boc 2 O (5.83 g, 0.026 mol) was added drop wise to a stirred solution of 3-amino-1-propanol 9 (1.744 g, 0... were recorded on a MicroMass ES- QTOF. Chiral HPLC analysis was executed using Jasco HPLC model MX-2080-31 instrument. Melting points were recorded using Thiele apparatus and are uncorrected. S2 2. Copies of 1 H NMR, 13 C NMR and DEPT...

  11. Ultrasonic and Volumetric Investigations of -Butyrolactone with Aliphatic Alcohols

    Directory of Open Access Journals (Sweden)

    Amara Jyothi Koppula

    2014-08-01

    Full Text Available Densities ( and speeds of sound (u have been determined for the binary liquid mixtures of -butyrolactone (GBL with 1-propanol (1-Pro, 2-propanol (2-Pro, 1-butanol (1-But and 2-butanol (2-But at 303.15, 308.15, and 313.15 K and entire composition range. From the experimental results, the excess molar volume (V E , and deviation in isentropic compressibility (s were calculated. The computed properties have been fitted to a Redlich-Kister type polynomial equation to derive binary coefficients and standard deviations.

  12. 2-甲基-3-丁烯-2-醇+直链一元醇二元体系的过量摩尔体积和表观摩尔体积298.15 K)%Excess Molar Volume and Apparent Molar Volume of Binary Mixtures of 2-Methyl-3-buten-2-ol with 1-Alcohol at 298.15 K

    Institute of Scientific and Technical Information of China (English)

    刘迪霞; 李浩然; 邓东顺; 韩世钧

    2002-01-01

    Excess molar volumes (VEm) of binary mixtures of 2-methyl-3-buten-2-ol [CH3C(OH)(CH3)CHCH2]with four 1-alcohols: methanol, ethanol, 1-propanol and 1-butanol at 298.15 K and atmospheric pressure are derived from density measurements with a vibrating-tube densimeter. All the excess volumes are negative in the systems over the entire composition range. The results are correlated with the Redlich-Kister equation. The effects of chain length of 1-alcohols on VmE are discussed. The apparent molar volumes of 2-methyl-3-buten-2-ol and 1-alcohols are calculated respectively.

  13. Synthesis of Non-Cytotoxic Poly(Ester-Amine Dendrimers as Potential Solubility Enhancers for Drugs: Methotrexate as a Case Study

    Directory of Open Access Journals (Sweden)

    Patricia Guadarrama

    2010-11-01

    Full Text Available This study describes the synthesis of two new families of dendrimers based on the esterification of N-alkylated 3-amine-1-propanol with two different cores, adipic acid (1st and 2nd generations and ethylenediamine (generation 1.5, both with carboxylic acid end groups, offering a wide variety of further modifications at the periphery. According to the cytotoxic evaluation of the dendrimers and their possible degradation products within cell lines, these materials could be considered as innocuous. In preliminary studies, the synthesized dendrimers proved to be potential enhancers of solubility of highly hydrophobic drugs, like methotrexate, widely used in chemotherapy.

  14. Steam reforming of light oxygenates

    DEFF Research Database (Denmark)

    Trane-Restrup, Rasmus; Resasco, Daniel E; Jensen, Anker Degn

    2013-01-01

    Steam reforming (SR) of ethanol, acetic acid, acetone, acetol, 1-propanol, and propanal has been investigated over Ni/MgAl2O4 at temperatures between 400 and 700 degrees C and at a steam-to-carbon-ratio (S/C) of 6. The yield of H-2 and conversion increased with temperature, while the yield of by-...... of CH4. Significant deactivation of the catalyst was observed for all of the compounds and was mainly due to carbon formation. The carbon formation was highest for alcohols due to a high formation of olefins, which are potent coke precursors....

  15. Cluster formation restricts dynamic nuclear polarization of xenon in solid mixtures

    DEFF Research Database (Denmark)

    Kuzma, N. N.; Pourfathi, M.; Kara, H.;

    2012-01-01

    During dynamic nuclear polarization (DNP) at 1.5 K and 5 T, Xe-129 nuclear magnetic resonance (NMR) spectra of a homogeneous xenon/1-propanol/trityl-radical solid mixture exhibit a single peak, broadened by H-1 neighbors. A second peak appears upon annealing for several hours at 125 K. Its....... Subsequent DNP system modifications designed to reduce the overheating resulted in four-fold increase of Xe-129 polarization, from 5.3% to 21%. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4751021]...

  16. Measurement and correlation of solubility of trans-resveratrol in 11 solvents at T = (278.2, 288.2, 298.2, 308.2, and 318.2) K

    Energy Technology Data Exchange (ETDEWEB)

    Sun Xilan; Peng Bin [Department of Chemistry, Zhejiang University, Hangzhou 310027 (China); Yan Weidong [Department of Chemistry, Zhejiang University, Hangzhou 310027 (China)], E-mail: yanweidong@zju.edu.cn

    2008-04-15

    The solubilities of trans-resveratrol in methanol, ethanol, 1-propanol, 2- propanol, 1-butanol, 1-pentanol, 1-hexanol, ethyl acetate, tetrahydrofuran, acetone, and water (pH 6.0) solvents were measured at T = (278.2, 288.2, 298.2, 308.2, and 318.2) K. The solubilities of trans-resveratrol in selected solvents increase with temperature, but decrease with increasing the number of carbon in alcohol solvents. The experimental data were correlated using a thermodynamic equation.

  17. DINAMIKA NASTAJANJA VIŠJIH ALKOHOLOV IN ESTROV V FERMENTIRANIH PIJAČAH IZ JEČMENOVEGA, KVINOJINEGA IN AJDOVEGA SLADU

    OpenAIRE

    Brečko, Natalija

    2014-01-01

    Namen diplomskega dela je bila uvedba in validacija analizne metode za določanje višjih alkoholov in estrov v pivu in pivu podobnih pijačah v odvisnosti od surovine in zaporednega števila fermentacij. Omenjene spojine v pivu nastajajo kot stranski produkti med procesom fermentacije in prispevajo predvsem k aromi piva tako v pozitivnem kot v negativnem smislu. Pomembnejši alkoholi v pivu, ki smo jih določali so: metanol, 1-propanol, izobutanol (IUPAC nomenklatura: 2-metilpropan-1-ol), 2-met...

  18. Volatile metabolites from actinomycetes

    DEFF Research Database (Denmark)

    Scholler, C.E.G.; Gurtler, H.; Pedersen, R.;

    2002-01-01

    , sulfur compounds, and isoprenoid compounds. Among the most frequently produced compounds were isoprene, acetone, 1-butanol, 2-methyl-1-propanol,3-methyl-3-buten-1-ol, 3-methyl-1-butanol, 2-methyl-1-butanol, cyclopentanone, dimethyl disulfide, dimethyl trisulfide, 2-phenylethanol, and geosmin....... The relationship between the excretion of geosmin and the production of spores was examined for one isolate. A good correlation between headspace geosmin and the number of spores was observed, suggesting that VOCs could be used to indicate the activity of these microorganisms in heterogeneous substrates....

  19. The lipid moiety of brincidofovir is required for in vitro antiviral activity against Ebola virus.

    Science.gov (United States)

    McMullan, Laura K; Flint, Mike; Dyall, Julie; Albariño, César; Olinger, Gene G; Foster, Scott; Sethna, Phiroze; Hensley, Lisa E; Nichol, Stuart T; Lanier, E Randall; Spiropoulou, Christina F

    2016-01-01

    Brincidofovir (BCV) is the 3-hexadecyloxy-1-propanol (HDP) lipid conjugate of the acyclic nucleoside phosphonate cidofovir (CDV). BCV has established broad-spectrum activity against double-stranded DNA (dsDNA) viruses; however, its activity against RNA viruses has been less thoroughly evaluated. Here, we report that BCV inhibited infection of Ebola virus in multiple human cell lines. Unlike the mechanism of action for BCV against cytomegalovirus and other dsDNA viruses, phosphorylation of CDV to the diphosphate form appeared unnecessary. Instead, antiviral activity required the lipid moiety and in vitro activity against EBOV was observed for several HDP-nucleotide conjugates.

  20. Vapor-Liquid Equilibrium of Ethyl Acetate+C_nH_(2n+1)OH(n=1,2,3) Binary Systems at 0.3 MPa

    Institute of Scientific and Technical Information of China (English)

    SUSIAL P.; RODRIGUEZ-HENRIQUEZ J.J.; SOSA-ROSARIO A.; RIOS-SANTANA R.

    2012-01-01

    Vapor-liquid equilibrium data for the binary systems of ethyl acetate + methanol,ethyl acetate + ethanol and ethyl acetate + 1-propanol at 0.3 MPa were determined.The experimental data were verified with the point-to-point test of van Ness(1973).All these systems present an azeotropic point at 0.3 MPa that increases in ester composition for longer alcohol chains.The UNIFAC in different versions and ASOG prediction models were applied.

  1. Self-reduction of a copper complex MOD ink for inkjet printing conductive patterns on plastics.

    Science.gov (United States)

    Farraj, Yousef; Grouchko, Michael; Magdassi, Shlomo

    2015-01-31

    Highly conductive copper patterns on low-cost flexible substrates are obtained by inkjet printing a metal complex based ink. Upon heating the ink, the soluble complex, which is composed of copper formate and 2-amino-2-methyl-1-propanol, decomposes under nitrogen at 140 °C and is converted to pure metallic copper. The decomposition process of the complex is investigated and a suggested mechanism is presented. The ink is stable in air for prolonged periods, with no sedimentation or oxidation problems, which are usually encountered in copper nanoparticle based inks. PMID:25482984

  2. A novel route to synthesis of glycerol dimethyl ether from epichlorohydrin with high selectivity

    International Nuclear Information System (INIS)

    The effective utilization of glycerol, a by-product in the production of biodiesel, into useful chemicals is desirable from the viewpoint of green chemistry. With this in mind, a novel and highly selective route to synthesizing glycerol dimethyl ether (2,3-dimethoxy-1-propanol), a potential fuel additive, from glycerol was proposed. This route uses both glycerol and methanol as starting materials, takes epichlorohydrin as an intermediate product, and utilizes HCl as a recycling agent. Hereinto, the key step of this route is the reaction between epichlorohydrin and methanol to produce 2,3-dimethoxy-1-propanol which is identified by GC–MS, ESI-MS, IR and NMR. The thermodynamics of this reaction was analyzed and the result showed that the thermodynamics of a reaction was favorable and a high product yield was expected. The effect of various parameters such as kind of acid catalyst, molar ratio of epichlorohydrin to methanol, reaction temperature and reaction time was studied. Among various acid catalysts investigated, the acidic ionic liquid [HSO3-b-N(CH3)3]HSO4 exhibited the highest activity and selectivity: conversion of epichlorohydrin of 100% and selectivity of 2,3-dimethoxy-1-propanol of 99% at 393 K, 10 h, an initial pressure of 0.1 MPa and a molar ratio of catalyst:ECH:CH3OH of 0.01:1:5. After the reaction, [HSO3-b-N(CH3)3]HSO4 was separated by vacuum distillation and then reused for the next cycle directly. The results showed that the product selectivity remained at about 94% but the conversion of epichlorohydrin dropped to 75% after being used five times. Subsequently, a reaction mechanism for the synthesis of 2,3-dimethoxy-1-propanol from epichlorohydrin and methanol was proposed. - Highlights: • Epichlorohydrin was converted effectively into glycerol dimethyl ether used as potential fuel additive. • The selectivity of 99% and the conversion of 100% under the mild reaction condition. • The reaction was high product selectivity and yield, mild

  3. Transferência de energia entre corantes catiônicos em sistemas homogêneos

    Directory of Open Access Journals (Sweden)

    Oliveira Hueder Paulo Moisés de

    2003-01-01

    Full Text Available In this work, the energy transfer by dipole-dipole interaction between cationic dyes in n-alcohols (methanol, ethanol, 1-propanol and 1-butanol is studied by time resolved and steady state fluorescence measurements. The critical radii of energy transfer were determined by three independent methods; the spectral overlap, fluorescence decay profiles, and relative intensity measurements. In all solvents, R0 values of the dye pairs obtained from spectral overlap were between 40 to 90 Å. Steady state and time resolved fluorescence measurements resulted in values of R0 in the range of 50 - 80 Å, with good correlation of values.

  4. Third derivative thermodynamic quantities of aqueous tetrahydrofuran at 25 degrees C

    DEFF Research Database (Denmark)

    Westh, Peter; Yoshida, Koh; Inaba, Akira;

    2015-01-01

    We measured the excess chemical potential, μΕTHF, the excess partial molar enthalpy and entropy of solute tetrahydrofuran (THF), HETHF and SETHF, in THF–H2O at 25 °C. Using these second derivatives of G, we graphically evaluated the third derivative quantities; the enthalpic, entropic THF–THF int......, THF is as amphiphilic as ME. A quantitative characterization and any difference between THF and ME ought to wait for characterization by the 1-propanol probing methodology developed by us [PCCP 15(2013) 14548-14565]...

  5. New Chiral Metal Cluster Systems for Catalytic Asymmetric Syntheses of Chiral Alcohols

    Institute of Scientific and Technical Information of China (English)

    LI Yan-yun; CHEN Jian-shan; YANG Chuan-bo; DONG Zhen-rong; LI Bao-zhu; ZHANG Hui; GAO Jing-xing; TAKAO Ikariya

    2004-01-01

    The efficient chiral Ru3(CO)12 systems were prepared in situ from Ru3(CO)12 and various chiral diiminoor diamino-diphosphine tetradentate ligands. The systems have been used for the asymmetric transfer hydrogenation of propiophenone in 2-propanol, leading to 1-phenyl-1-propanol in a 98% yield and 96% e.e. The IR study suggests that the carbonyl hydride anion [HRu3(CO)11]- most probably exists as a principal species under the reaction conditions. The high chiral efficiency may be due to the synergetic effect produced by the neighboring ruthenium atoms and a special chiral micro-environment involving the polydentate ligand and the Ru3 framework.

  6. Determination and correlation of the solubility of four Brønsted-acidic ionic liquids based on benzothiazolium cations in six alcohols

    International Nuclear Information System (INIS)

    Highlights: • Solubility of four acidic benzothiazolium cations-based ILs was measured. • The solubilities vary with the polarity of the solvent. • The solubility of some ILs is with “temperature-sensitive” property. • The measured solubilities were correlated by Apelblat model and λh model. • The dissolution enthalpy and entropy of ILs were calculated using the van’t Hoff equation. - Abstract: Solubilities of four acidic ionic liquids based on benzothiazolium cations in six alcohols (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol and 2-methyl-1-propanol) from at temperatures from (253 to 384) K were determined using a static equilibrium method under atmospheric pressure. The modified Apelblat equation and λh equation were employed to correlate the experimental data with good agreement. The solubilities of ILs increase with increasing temperature. It is interesting to find that the solubility of some ILs in alcohols are with “temperature-sensitive” properties. The solubility is related with the polarity and molecular structures of the solvent, as well as the strength of hydrogen bonding between alcohols and anionic groups of ILs. The dissolution enthalpy and entropy of ILs were calculated by the van’t Hoff equation. This study provides useful information for further research and application of the ionic liquids

  7. FTIR/PCA study of propanol in argon matrix: the initial stage of clustering and conformational transitions

    International Nuclear Information System (INIS)

    FTIR spectra of 1-propanol in an argon matrix were studied in the range 11 to 30 K. Principal component analysis of dynamic FTIR spectra and nonlinear band shape fitting has been carried out. The peaks of monomer, open dimer, mixed propanol-water dimer and those of higher H-bond clusters have been resolved and analyzed. The attribution of certain FTIR peaks has been supported by proper density functional theory calculations. Analyzing dependences of the integral band intensities of various aggregates on temperature it has been deduced that in the initial stage of clustering monomers and dimers are the basic building blocks forming higher H-bond clusters. The peaks assigned to two conformers of monomers and mixed propanol-water dimers were investigated processing the temperature dependences of their integral intensities in Arrhenius plot. The obtained values of 0.18 kJ.mol-1 for propanol monomer and 0.26 kJ.mol-1 for mixed dimer are well comparable with the energy differences between the global minimum conformation of 1-propanol (Gt) and some other energetically higher structures (Tt or Tg).

  8. Influence of the composition of aqueous-alcohol solvents on the thermodynamic characteristics of L-phenylalanine dissolution at 298.15 K

    Energy Technology Data Exchange (ETDEWEB)

    Badelin, Valentin G. [Laboratory of Thermodynamics of Solutions of Non-electrolytes and Biologically Active Substances, Institute of Solution Chemistry, Russian Academy of Sciences, 1 Akademicheskaya Street, 153045, Ivanovo (Russian Federation); Smirnov, Valeriy I., E-mail: vis@isc-ras.ru [Laboratory of Thermodynamics of Solutions of Non-electrolytes and Biologically Active Substances, Institute of Solution Chemistry, Russian Academy of Sciences, 1 Akademicheskaya Street, 153045, Ivanovo (Russian Federation)

    2011-11-10

    Highlights: Black-Right-Pointing-Pointer Enthalpies of L-phenylalanine dissolution have been measured in aqueous methanol, ethanol, 1-propanol and 2-propanol. Black-Right-Pointing-Pointer The measured data were reported as functions of composition of water + alcohol mixtures. Black-Right-Pointing-Pointer Enthalpy coefficients of pair-wise interactions have been analyzed in terms of McMillan-Mayer theory. Black-Right-Pointing-Pointer A comparative analysis of the characteristics of dissolution of L-phenylalanine and some other L-amino acids in the similar systems has been made. - Abstract: The enthalpies of L-phenylalanine dissolution in aqueous methanol, ethanol, 1-propanol and 2-propanol have been determined by calorimetry at 298.15 K and alcohol mole fractions up to x{sub 2} {approx}0.4. The standard enthalpies of solution {Delta}{sub sol}H Degree-Sign and transfer {Delta}{sub tr}H Degree-Sign from water to the mixed solvent as well as the enthalpy coefficients of L-phenylalanine-alcohol pair-wise interactions were calculated. The interrelation of the enthalpies of dissolution and transfer for L-phenylalanine with structural features of alcohols has been determined. A comparative analysis of the thermodynamic characteristics of dissolution of L-phenylalanine and some other amino acids (glycine, L-alanine, L-threonine and L-valine) in the mixtures studied has been made.

  9. Thermodynamic properties of binary liquid mixtures of diethylenetriamine with alcohols at different temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Dubey, Gyan Prakash, E-mail: gyan.dubey@rediffmail.com [Department of Chemistry, Kurukshetra University, Kurukshetra 136119 (India); Kumar, Krishan [Department of Chemistry, Kurukshetra University, Kurukshetra 136119 (India)

    2011-09-20

    Highlights: {yields} Thermodynamic study of diethylenetriamine + 2-methyl-1-propanol, +2-propanol or +1-butanol have been made. {yields} Excess molar volumes and isentropic compressibility were determined. {yields} Types of interactions were discussed based on derived properties. - Abstract: Densities, {rho}, viscosities, {eta}, and speeds of sound, u, were measured for the binary liquid mixtures containing diethylenetriamine with 2-methyl-1-propanol, 2-propanol and 1-butanol at 293.15, 298.15, 303.15, 308.15 and 313.15 K. From density and speed of sound data, excess molar volumes, V{sub m}{sup E} and deviations in isentropic compressibility, {Delta}{kappa}{sub s}, and speed of sound, {Delta}u have been evaluated. Viscosity data were used to compute deviations in viscosity and excess Gibbs energy of activation of viscous flow {Delta}G*{sup E} at 298.15, 303.15 and 308.15 K. A Redlich-Kister type equation was applied to fit the excess molar volumes and deviations in isentropic compressibility, speed of sound and viscosity data. The viscosity data have been correlated with the equations of Grunberg-Nissan, Tamura-Kurata, Heric-Brewer and of Hind et al. All the binary systems of the present study have negative values of excess molar volumes and deviations in isentropic compressibility over whole composition range and at all temperatures which indicates strong interactions between the components of binary mixtures.

  10. Microemulsion System for Topical Delivery of Thai Mango Seed Kernel Extract: Development, Physicochemical Characterisation and Ex Vivo Skin Permeation Studies

    Directory of Open Access Journals (Sweden)

    Jiraporn Leanpolchareanchai

    2014-10-01

    Full Text Available A microemulsion system containing Thai mango seed kernel extract (MSKE, cultivar “Fahlun” was developed and characterised for the purpose of topical skin delivery. The MSKE-loaded microemulsions were prepared by using the spontaneous emulsification method. Isopropyl myristate (IPM was selected as the oil phase. A polyoxyethylene sorbitan monooleate and sorbitan monododecanoate (1:1, w/w system was used as the surfactant phase; an aqueous mixture of different cosurfactants (absolute ethanol, 96.3% v/v ethanol, 1-propanol, 2-propanol or 1,2-propanediol at a weight ratio of 1:1 was used as the aqueous phase. Among the cosurfactants studied, the 1-propanol aqueous mixture had the largest microemulsion region (48.93% in the pseudo-ternary phase diagram. Microemulsions containing 1% MSKE demonstrated good physicochemical stability during a six-month study period at 25 ± 2 °C/60% ± 5% RH. The ex vivo skin permeation study demonstrated that the microemulsions exhibited a potent skin enhancement effect allowing MSKE to penetrate skin layers up to 60-fold higher compared with the control. Neither skin irritation nor skin corrosion was observed in ex vivo studies. The present study revealed that IPM-based microemulsion systems may be promising carriers to enhance skin penetration and delivering MSKE for topical treatment.

  11. Single-walled carbon nanotube-based polymer monoliths for the enantioselective nano-liquid chromatographic separation of racemic pharmaceuticals.

    Science.gov (United States)

    Ahmed, Marwa; Yajadda, Mir Massoud Aghili; Han, Zhao Jun; Su, Dawei; Wang, Guoxiu; Ostrikov, Kostya Ken; Ghanem, Ashraf

    2014-09-19

    Single-walled carbon nanotubes were encapsulated into different polymer-based monolithic backbones. The polymer monoliths were prepared via the copolymerization of 20% monomers, glycidyl methacrylate, 20% ethylene glycol dimethacrylate and 60% porogens (36% 1-propanol, 18% 1,4-butanediol) or 16.4% monomers (16% butyl methacrylate, 0.4% sulfopropyl methacrylate), 23.6% ethylene glycol dimethacrylate and 60% porogens (36% 1-propanol, 18% 1,4-butanediol) along with 6% single-walled carbon nanotubes aqueous suspension. The effect of single-walled carbon nanotubes on the chiral separation of twelve classes of pharmaceutical racemates namely; α- and β-blockers, antiinflammatory drugs, antifungal drugs, dopamine antagonists, norepinephrine-dopamine reuptake inhibitors, catecholamines, sedative hypnotics, diuretics, antihistaminics, anticancer drugs and antiarrhythmic drugs was investigated. The enantioselective separation was carried out under multimodal elution to explore the chiral recognition capabilities of single-walled carbon nanotubes using reversed phase, polar organic and normal phase chromatographic conditions using nano-liquid chromatography. Baseline separation was achieved for celiprolol, chlorpheniramine, etozoline, nomifensine and sulconazole under multimodal elution conditions. Satisfactory repeatability was achieved through run-to-run, column-to-column and batch-to-batch investigations. Our findings demonstrate that single-walled carbon nanotubes represent a promising stationary phase for the chiral separation and may open the field for a new class of chiral selectors.

  12. Electron beam induced synthesis of uranium dioxide nanoparticles: Effect of solvent composition

    Science.gov (United States)

    Rath, M. C.; Keny, S. J.; Naik, D. B.

    2016-09-01

    The effect of various compositions of solvents was investigated on the electron beam induced synthesis of uranium dioxide, UO2 nanoparticles. The synthesis was carried out at different pHs from 2 to 7 in the aqueous solutions containing 10 mM uranyl nitrate and 10% 2-propanol. The formation of UO2 nanoparticles was found to occur only in the pH range from 2.5 to 3.7. Experiments were also carried out in the aqueous solutions containing various other alcohols (10% v/v) such as methanol, ethanol, 1-propanol, 1-butanol or tert-butanol as well as in solutions containing 10 mM sodium formate at pH 3.4. The formation of UO2 nanoparticles in the aqueous solutions was found to occur only in the presence of ethanol, 1-propanol, 2-propanol or 1-butanol. It is therefore confirmed that the electron beam induced synthesis of UO2 nanoparticles strongly depends on the solvent compositions as well as the pH of the medium.

  13. Microemulsion system for topical delivery of thai mango seed kernel extract: development, physicochemical characterisation and ex vivo skin permeation studies.

    Science.gov (United States)

    Leanpolchareanchai, Jiraporn; Padois, Karine; Falson, Françoise; Bavovada, Rapepol; Pithayanukul, Pimolpan

    2014-01-01

    A microemulsion system containing Thai mango seed kernel extract (MSKE, cultivar "Fahlun") was developed and characterised for the purpose of topical skin delivery. The MSKE-loaded microemulsions were prepared by using the spontaneous emulsification method. Isopropyl myristate (IPM) was selected as the oil phase. A polyoxyethylene sorbitan monooleate and sorbitan monododecanoate (1:1, w/w) system was used as the surfactant phase; an aqueous mixture of different cosurfactants (absolute ethanol, 96.3% v/v ethanol, 1-propanol, 2-propanol or 1,2-propanediol) at a weight ratio of 1:1 was used as the aqueous phase. Among the cosurfactants studied, the 1-propanol aqueous mixture had the largest microemulsion region (48.93%) in the pseudo-ternary phase diagram. Microemulsions containing 1% MSKE demonstrated good physicochemical stability during a six-month study period at 25 ± 2 °C/60% ± 5% RH. The ex vivo skin permeation study demonstrated that the microemulsions exhibited a potent skin enhancement effect allowing MSKE to penetrate skin layers up to 60-fold higher compared with the control. Neither skin irritation nor skin corrosion was observed in ex vivo studies. The present study revealed that IPM-based microemulsion systems may be promising carriers to enhance skin penetration and delivering MSKE for topical treatment. PMID:25347456

  14. Hydrophobic and hydrophilic interactions in aqueous mixtures of alcohols at a hydrophobic surface.

    Science.gov (United States)

    Ballal, Deepti; Chapman, Walter G

    2013-09-21

    Aqueous solutions of alcohols are interesting because of their anomalous behavior that is believed to be due to the molecular structuring of water and alcohol around each other in solution. The interfacial structuring and properties are significant for application in alcohol purification processes and biomolecular structure. Here we study aqueous mixtures of short alcohols (methanol, ethanol, 1-propanol, and 2-propanol) at a hydrophobic surface using interfacial statistical associating fluid theory which is a perturbation density functional theory. The addition of a small amount of alcohol decreases the interfacial tension of water drastically. This trend in interfacial tension can be explained by the structure of water and alcohol next to the surface. The hydrophobic group of an added alcohol preferentially goes to the surface preserving the structure of water in the bulk. For a given bulk alcohol concentration, water mixed with the different alcohols has different interfacial tensions with propanol having a lower interfacial tension than methanol and ethanol. 2-propanol is not as effective in decreasing the interfacial tension as 1-propanol because it partitions poorly to the surface due to its larger excluded volume. But for a given surface alcohol mole fraction, all the alcohol mixtures give similar values for interfacial tension. For separation of alcohol from water, methods that take advantage of the high surface mole fraction of alcohol have advantages compared to separation using the vapor in equilibrium with a water-alcohol liquid.

  15. Measurement and modeling of high-pressure (vapour + liquid) equilibria of (CO{sub 2} + alcohol) binary systems

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez, Jorge E.; Bejarano, Arturo [Departamento de Ingenieria Quimica y Ambiental, Universidad Tecnica Federico Santa Maria, Avda. Espana 1680, Valparaiso (Chile); Fuente, Juan C. de la, E-mail: juan.delafuente@usm.c [Departamento de Ingenieria Quimica y Ambiental, Universidad Tecnica Federico Santa Maria, Avda. Espana 1680, Valparaiso (Chile); Centro Regional de Estudios en Alimentos Saludables, Blanco 1623, Valparaiso (Chile)

    2010-05-15

    An apparatus based on a static-analytic method assembled in this work was utilized to perform high pressure (vapour + liquid) equilibria measurements with uncertainties estimated at <5%. Complementary isothermal (vapour + liquid) equilibria results are reported for the (CO{sub 2} + 1-propanol), (CO{sub 2} + 2-methyl-1-propanol), (CO{sub 2} + 3-methyl-1-butanol), and (CO{sub 2} + 1-pentanol) binary systems at temperatures of (313, 323, and 333) K, and at pressure range of (2 to 12) MPa. For all the (CO{sub 2} + alcohol) systems, it was visually monitored to insure that there was no liquid immiscibility at the temperatures and pressures studied. The experimental results were correlated with the Peng-Robinson equation of state using the quadratic mixing rules of van der Waals with two adjustable parameters. The calculated (vapour + liquid) equilibria compositions were found to be in good agreement with the experimental values with deviations for the mol fractions <0.12 and <0.05 for the liquid and vapour phase, respectively.

  16. Determination and Correlation of Solubilities of Four Novel Benzothiazolium Ionic Liquids with 6PF- in Six Alcohols

    Institute of Scientific and Technical Information of China (English)

    何志坚; 王小敏; 姚田; 宋航; 姚舜

    2014-01-01

    Four novel benzothiazolium ionic liquids with 6PF- ([C1Bth][PF6], [C4Bth][PF6], [C5Bth][PF6] and [C6Bth][PF6]) were synthesized, and the rang of their melting points were determined between 358.35 K-424.05 K. The relationship of their melting points and the length of the straight alkyl chain on cation reflected‘S’ type ten-dency. Then, the solubilities of the four ionic liquids in six lower alcohols (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol and 2-methyl-1-propanol) were measured in the temperature rang of 253.15-383.15 K at at-mospheric pressure with static analytical method, respectively. It was found that [C6Bth][PF6] in all investigated ionic liquids had the largest solubility in six alcohols and the solubility of [C4Bth][PF6] in methanol was very sensi-tive for temperature in 313.15-333.15 K, which was so-called “temperature-sensitivity”. This feature is of great significance to their application of catalyzing reaction or extraction process, and makes the recovery and reuse of ionic liquids (ILs) become easier. Moreover, the experimental solubility data were correlated with the modified Apelblat equation andλh equation, respectively. It was found that the result of correlation using two divided tem-perature ranges was better than that of using the whole temperature range.

  17. Odorous gaseous emissions as influence by process condition for the forced aeration composting of pig slaughterhouse sludge

    Energy Technology Data Exchange (ETDEWEB)

    Blazy, V., E-mail: vincent.blazy@irstea.fr [Irstea, UR GERE, 17 Avenue de Cucillé, CS 64427, F-35044 Rennes (France); Guardia, A. de, E-mail: amaury.de-guardia@irstea.fr [Irstea, UR GERE, 17 Avenue de Cucillé, CS 64427, F-35044 Rennes (France); Benoist, J.C; Daumoin, M. [Irstea, UR GERE, 17 Avenue de Cucillé, CS 64427, F-35044 Rennes (France); Lemasle, M.; Wolbert, D. [Laboratoire Sciences Chimiques de Rennes - équipe Chimie et Ingénierie des Procédés, UMR 6226 CNRS, ENSCR, Avenue du Général Leclerc, 35700 Rennes (France); Barrington, S., E-mail: suzellebarrington@sympatico.ca [Irstea, UR GERE, 17 Avenue de Cucillé, CS 64427, F-35044 Rennes (France); Concordia University, Department of Building, Civil and Environmental Engineering, 1455 de Maisonneuve, Montréal, QC H3G 1M8 (Canada)

    2014-07-15

    Highlights: • The gaseous emissions produced by various composting process conditions were characterized and quantified. • Nine compounds were potentially odorous: TMA, NH{sub 3}, 2-pentanone, 1-propanol-2-methyl, acetophenone and sulphur forms. • The tested composting process conditions reduced odour emissions by a factor of 5–10. • A reduction of 10{sup 5} to 10{sup 6} is required to reach an odour threshold limit at peak event emissions. • Both aeration rate and bulking agent had the most impact on reducing odour emissions. - Abstract: Compost sustainability requires a better control of its gaseous emissions responsible for several impacts including odours. Indeed, composting odours have stopped the operation of many platforms and prevented the installation of others. Accordingly, present technologies collecting and treating gases emitted from composting are not satisfactory and alternative solutions must be found. Thus, the aim of this paper was to study the influence of composting process conditions on gaseous emissions. Pig slaughterhouse sludge mixed with wood chips was composted under forced aeration in 300 L laboratory reactors. The process conditions studied were: aeration rate of 1.68, 4.03, 6.22, 9.80 and 13.44 L/h/kg of wet sludge; incorporation ratio of 0.55, 0.83 and 1.1 (kg of wet wood chips/kg of wet sludge), and; bulking agent particles size of <10, 10 < 20 and 20 < 30 mm. Out-going gases were sampled every 2 days and their composition was analysed using gas chromatography coupled with mass spectrometry (GC–MS). Fifty-nine compounds were identified and quantified. Dividing the cumulated mass production over 30 days of composting, by odour threshold, 9 compounds were identified as main potential odour contributors: hydrogen sulphide, trimethylamine, ammonia, 2-pentanone, 1-propanol-2-methyl, dimethyl sulphide, dimethyl disulphide, dimethyl trisulphide and acetophenone. Five gaseous compounds were correlated with both aeration rate and

  18. Potassium sorbate reduces production of ethanol and 2 esters in corn silage.

    Science.gov (United States)

    Hafner, Sasha D; Franco, Roberta B; Kung, Limin; Rotz, C Alan; Mitloehner, Frank

    2014-12-01

    The objective of this work was to evaluate the effects of biological and chemical silage additives on the production of volatile organic compounds (VOC; methanol, ethanol, 1-propanol, methyl acetate, and ethyl acetate) within corn silage. Recent work has shown that silage VOC can contribute to poor air quality and reduce feed intake. Silage additives may reduce VOC production in silage by inhibiting the activity of bacteria or yeasts that produce them. We produced corn silage in 18.9-L bucket silos using the following treatments: (1) control (distilled water); (2) Lactobacillus buchneri 40788, with 400,000 cfu/g of wet forage; (3) Lactobacillus plantarum MTD1, with 100,000 cfu/g; (4) a commercial buffered propionic acid-based preservative (68% propionic acid, containing ammonium and sodium propionate and acetic, benzoic, and sorbic acids) at a concentration of 1 g/kg of wet forage (0.1%); (5) a low dose of potassium sorbate at a concentration of 91 mg/kg of wet forage (0.0091%); (6) a high dose of potassium sorbate at a concentration of 1g/kg of wet forage (0.1%); and (7) a mixture of L. plantarum MTD1 (100,000 cfu/g) and a low dose of potassium sorbate (91 mg/kg). Volatile organic compound concentrations within silage were measured after ensiling and sample storage using a headspace gas chromatography method. The high dose of potassium sorbate was the only treatment that inhibited the production of multiple VOC. Compared with the control response, it reduced ethanol by 58%, ethyl acetate by 46%, and methyl acetate by 24%, but did not clearly affect production of methanol or 1-propanol. The effect of this additive on ethanol production was consistent with results from a small number of earlier studies. A low dose of this additive does not appear to be effective. Although it did reduce methanol production by 24%, it increased ethanol production by more than 2-fold and did not reduce the ethyl acetate concentration. All other treatments increased ethanol production

  19. Ionic association and solvation of the ionic liquid 1-hexyl-3-methylimidazolium chloride in molecular solvents revealed by vapor pressure osmometry, conductometry, volumetry, and acoustic measurements.

    Science.gov (United States)

    Sadeghi, Rahmat; Ebrahimi, Nosaibah

    2011-11-17

    A systematic study of osmotic coefficient, conductivity, volumetric and acoustic properties of solutions of ionic liquid 1-hexyl-3-methylimidazolium chloride ([C(6)mim][Cl]) in various molecular solvents has been made at different temperatures in order to study of ionic association and solvation behavior of [C(6)mim][Cl] in different solutions. Precise measurements on electrical conductances of solutions of [C(6)mim][Cl] in water, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, and acetonitrile at 293.15, 298.15, and 303.15 K are reported and analyzed with Barthel's low-concentration chemical model (lcCM) to obtain the limiting molar conductivities and association constants of this ionic liquid in the investigated solvents. Strong ion pairing was found for the ionic liquid in 2-propanol, 1-butanol, and 1-propanol, whereas ion association in acetonitrile, methanol and ethanol is rather weak and in water the ionic liquid is fully dissociated. In the second part of this work, the apparent molar volumes and isentropic compressibilities of [C(6)mim][Cl] in water, methanol, ethanol, acetonitrile, 1-propanol, 2-propanol, and 1-butanol are obtained at the 288.15-313.15 K temperature range at 5 K intervals at atmospheric pressure from the precise measurements of density and sound velocity. The infinite dilution apparent molar volume and isentropic compressibility values of the free ions and ion pairs of [C(6)mim][Cl] in the investigated solvents as well as the excess molar volume of the investigated solutions are determined and their variations with temperature and type of solvents are also studied. Finally, the experimental measurements of osmotic coefficient at 318.15 K for binary solutions of [C(6)mim][Cl] in water, methanol, ethanol, 2-propanol, and acetonitrile are taken using the vapor pressure osmometry (VPO) method and from which the values of the solvent activity, vapor pressure, activity coefficients, and Gibbs free energies are calculated. The results are

  20. Gas-Chromatographic Analysis of Major Volatile Compounds Found in Traditional Fruit Brandies from Transylvania, Romania

    Directory of Open Access Journals (Sweden)

    Teodora Emilia RUSU COLDEA

    2011-11-01

    Full Text Available In the current study, the major volatile compounds from three categories of traditional fruit brandies (plum, apple and pear were characterized by gas-chromatography (GC-FID. There were collected 26 samples from different locations of Transylvania (Romania, all made by traditional technologies involving fermentation in barrels and distillation in copper stills. The major volatile compounds, besides ethanol, identified and quantified were: acetaldehyde, ethyl acetate, methanol, 1-propanol, 2-butanol, iso-butylic alcohol, alcool amyl active, iso-amylic alcohol, 1-butanol and furfural. For each type of brandy, positive but no significant correlations between methanol and furfural concentrations in plum and apple brandy were noticed. To evaluate the differences in composition regarding the geographical origin of plum brandies and to analyze the composition of plum, apple and pear brandies it has been compared the mean values (MVP, MVA and MVPe obtained for each volatile. For plum brandies it has been observed differences among the mean values of each volatile, in samples originating from counties Cluj, Bistriţa-Năsăud and Maramureş. For methanol, acetaldehyde and 1-propanol the MVP Cluj values were significantly higher than MVP Bistriţa-Năsăud. For iso-butylic alcohol, amyl active alcohol, iso-amylic alcohol the MVP Cluj values were significantly higher than for Bistriţa-Năsăud and Maramureş, while for ethyl acetate and furfural the MVP Bistriţa-Năsăud were significantly higher than MVP Cluj and MVP Maramureş. When compared the mean values of volatiles in plum vs apple vs pear brandies, for ethyl acetate, methanol, 2-butanol, 1-propanol and 1-butanol, the MVPe values were significantly higher than MVA, for furfural, amyl active and iso-amylic alcohols, while for acetaldehyde the MVPe values were significantly higher than MVP. Methanol represented the major volatile component, characteristic to fruit brandies, released by enzymatic

  1. A re-appraisal of the concept of ideal mixtures through a computer simulation study of the methanol-ethanol mixtures

    Science.gov (United States)

    Požar, Martina; Lovrinčević, Bernarda; Zoranić, Larisa; Mijaković, Marijana; Sokolić, Franjo; Perera, Aurélien

    2016-08-01

    Methanol-ethanol mixtures under ambient conditions of temperature and pressure are studied by computer simulations, with the aim to sort out how the ideality of this type of mixtures differs from that of a textbook example of an ideal mixture. This study reveals two types of ideality, one which is related to simple disorder, such as in benzene-cyclohexane mixtures, and another found in complex disorder mixtures of associated liquids. It underlines the importance of distinguishing between concentration fluctuations, which are shared by both types of systems, and the structural heterogeneity, which characterises the second class of disorder. Methanol-1propanol mixtures are equally studied and show a quasi-ideality with many respect comparable to that of the methanol-ethanol mixtures, hinting at the existence of a super-ideality in neat mono-ol binary mixtures, driven essentially by the strong hydrogen bonding and underlying hydroxyl group clustering.

  2. Relationship between membrane fluidity and capping of receptors for concanavalin A.

    Science.gov (United States)

    Mak, W W; Wong, J T

    1980-12-01

    The activities of a range of phenylalaninol-related compounds on capping of concanavalin A and induction of rounding of Chinese hamster ovary tsHl cells, as well as on the fluidity of phosphatidylcholine-cholesterol (1:1) liposomes, have been examined. These compounds include phenylalaninol, histidinol, leucinol, benzyl alcohol, benzylamine, 2-phenylethanol, 2-phenylamine, 3-phenyl-1-propanol, 3-phenyl-1-propylamine, and 3-phenylpropionic acid. The results indicate a strong correlation between the capacities of these compounds to enhance fluidity and their capacities to inhibit capping of concanavalin A. The specificity of this correlation is suggested by the finding that both types of capacities are poorly correlated with the capacities of the various compounds to induce cell rounding. PMID:6265046

  3. Measurement and Correlation for Solubility of Diosgenin in Some Mixed Solvents

    Institute of Scientific and Technical Information of China (English)

    陈飞雄; 赵明蕊; 冯露; 任保增

    2014-01-01

    The solubility data of diosgenin in mixed systems of ethanol+1-propanol (1︰1), ethanol+1-butanol (1︰1), ethanol+isobutyl alcohol (1︰1), methanol+isobutyl alcohol (1︰1), methanol+isobutyl alcohol (1︰4), ethanol+1-pentanol (1︰1) and carbon tetrachloride were measured over the temperature range from 289.15 K to 334.15 K by a laser monitoring observation technique at atmospheric pressure, with all mixtures mixed by volume ratio. The Apelblat equation, the ideal solution model, and theλh equation are used to correlate the solubility data. The results show that the three models agree well with the experimental data, providing essential support for industrial design and further theoretical study.

  4. Improved solvent formulations for efficient CO₂ absorption and low-temperature desorption.

    Science.gov (United States)

    Barzagli, Francesco; Di Vaira, Massimo; Mani, Fabrizio; Peruzzini, Maurizio

    2012-09-01

    This experimental study describes efficient CO₂ capture by 2-amino-2-methyl-1-propanol (AMP)/piperazine (PZ) in ethylene glycol monoethyl ether (EGMEE, 2-ethoxyethanol) containing approximately 15 wt % of water. In these experiments, the solvent is continuously circulated between the absorber (packed-bed reactor at 30, 40, or 45 °C) and the desorber (at 80, 85, or 90 °C). The CO₂ -solvent reaction equilibria have been investigated by using ¹³C NMR spectroscopy, which provides confirmatory evidence that the formation of mono- and biscarbamate derivatives of PZ accounts for most of the CO₂ absorbed by the AMP/PZ/EGMEE/H₂O blend. The solid-state structures of AMP carbamate and of the carbonate salt of protonated AMP have been determined by using XRD. Both AMPCO₂(-) and CO(3)(2-) species completely convert to the monoalkyl carbonates on dissolving the respective salts in methanol, ethanol, or ethylene glycol. PMID:22778091

  5. Quantum-chemical modeling of energy parameters and vibrational spectra of chain and cyclic clusters of monohydric alcohols

    Energy Technology Data Exchange (ETDEWEB)

    Golub, P., E-mail: pavelgolub87@gmail.com; Doroshenko, I.; Pogorelov, V.

    2014-05-01

    The specific peculiarities of alcohols such as heightened viscosity, boiling temperature and surface tension can be explained by the capability of their molecules to form relatively stable associates named clusters due to hydrogen bonding. In present work the stability of different chain-like and cyclic clusters of methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol and 1-hexanol was investigated by means of quantum-chemical simulation and particular by recently developed DFT exchange–correlation functional M06-2X. The relative stability of the cluster structure was evaluated by the total energy per molecule at low temperatures (where all alcohols exist in solid state) and by the changing of the free Gibbs energy upon cluster formation at the room temperature. For the verification of revealed results the conformity of calculated IR spectra of the most stable cluster structures with the experimental IR spectra at different temperatures was analyzed.

  6. Temperature dependent electron–phonon coupling in chlorin-doped impurity glass and in photosynthetic FMO protein containing bacteriochlorophyll a

    Energy Technology Data Exchange (ETDEWEB)

    Pajusalu, Mihkel; Rätsep, Margus [Institute of Physics, University of Tartu, 142 Riia Street, 51014 Tartu (Estonia); Freiberg, Arvi, E-mail: arvi.freiberg@ut.ee [Institute of Physics, University of Tartu, 142 Riia Street, 51014 Tartu (Estonia); Institute of Molecular and Cell Biology, University of Tartu, 23 Riia Street, 51010 Tartu (Estonia)

    2014-08-01

    Difference fluorescence line-narrowing spectra are studied for evaluating the temperature dependence of the linear electron–phonon and vibronic coupling strengths in the two weakly coupled low-temperature glassy systems: chlorin-doped 1-propanol and the native Fenna–Matthews–Olson (FMO) light-harvesting protein complex folded with bacteriochlophyll a chromophores. Roughly three-fold increases of the electron–phonon coupling strength and constant vibronic couplings were observed in both systems in the available temperature range from 4.5 to 70 K. However, while the chlorin system is amenable to simple modeling of impurity spectra, the FMO shows significant deviations, consistent with the complex (exciton) nature of its lowest-energy singlet electronic transition. - Highlights: We measured temperature dependence of spectra in chlorin-doped glass and FMO. We identified temperature dependences of linewidths and Huang–Rhys factors. Electron–phonon coupling increased about three times between 4.5 and 70 K.

  7. Comparison of chiral electrophoretic separation methods for phenethylamines and application on impurity analysis.

    Science.gov (United States)

    Borst, Claudia; Holzgrabe, Ulrike

    2010-12-15

    A chiral microemulsion electrokinetic chromatography method has been developed for the separation of the enantiomers of the phenethylamines ephedrine, N-methylephedrine, norephedrine, pseudoephedrine, adrenaline (epinephrine), 2-amino-1-phenylethanol, diethylnorephedrine, and 2-(dibutylamino)-1-phenyl-1-propanol, respectively. The separations were achieved using an oil-in-water microemulsion consisting of the oil-component ethyl acetate, the surfactant sodium dodecylsulfate, the cosurfactant 1-butanol, the organic modifier propan-2-ol and 20mM phosphate buffer pH 2.5 as aqueous phase. For enantioseparation sulfated beta-cyclodextrin was added. The method was compared to an already described CZE method, which made use of heptakis(2,3-di-O-diacetyl-6-O-sulfo)-beta-cyclodextrin (HDAS) as chiral selector. Additionally, the developed method was successfully applied to the related substances analysis of noradrenaline, adrenaline, dipivefrine, ephedrine and pseudoephedrine monographed in the European Pharmacopoeia 6.

  8. Catalytic activity of carbon nanotubes in the conversion of aliphatic alcohols

    Science.gov (United States)

    Zhitnev, Yu. N.; Tveritinova, E. A.; Chernyak, S. A.; Savilov, S. V.; Lunin, V. V.

    2016-06-01

    Carbon nanotubes (CNTs) obtained via the catalytic pyrolysis of hexane at 750°C were studied as the catalysts in conversion of C2-C4 alcohols. The efficiency of CNTs as catalysts in dehydration and dehydrogenation of ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, and tert-butanol was studied by means of pulse microcatalysis. The surface and structural characteristics of CNTs are investigated via SEM, TEM, DTA, BET, and XPS. CNTs are shown to be effective catalysts in the conversion of alcohols and do not require additional oxidative treatment. The regularities of the conversion of aliphatic alcohols, related to the properties of the CNTs surface and the structure of the alcohols are identified.

  9. Excess molar volumes of 1,3 propanediol + (C1-C5 alkan-1-ols: Application of cubic EOS

    Directory of Open Access Journals (Sweden)

    Almasi Mohammad

    2012-01-01

    Full Text Available Densities of the binary mixtures consist of methanol, ethanol, 1- propanol, 1-butanol and 1-pentanol with 1,3 Propanediol were measured at temperatures (293.15, 298.15, 303.15 and 313.15 K and atmospheric pressure. Measurements have been made over the full range of compositions and for the pure compounds by using a vibrating tube densimeter. Excess molar volumes have been obtained from these experimental results and were fitted to a Redlich-Kister type expansion. The results were interpreted in terms of molecular interactions and structural factors of the alcohols. It was observed that an increase of the alcohol carbon chain length led to lower interactions on mixing. The Peng-Robinson-Stryjek-Vera (PRSV equation of state has been used to correlate the binary excess molar volumes.

  10. Derived thermodynamic properties of alcohol + cyclohexylamine mixtures

    Directory of Open Access Journals (Sweden)

    IVONA R. RADOVIĆ

    2010-02-01

    Full Text Available Thermal expansion coefficients, α, excess thermal expansion coefficients, αE, isothermal coefficients of pressure excess molar enthalpy, (∂HE/∂pT,x, partial molar volumes, , partial molar volumes at infinite dilution, , partial excess molar volumes, , and partial excess molar volumes at infinite dilution, , were calculated using experimental densities and excess molar volumes, , data. All calculations are performed for the binary systems of cyclohexylamine with 1-propanol or 1-butanol or 2-butanol or 2-methyl-2-propanol. The Redlich–Kister polynomial and the reduced excess molar volume approach were used in the evaluation of these properties. In addition, the aim of this investigation was to provide a set of various volumetric data in order to asses the influence of temperature, chain length and position of hydroxyl group in the alcohol molecule on the molecular interactions in the examined binary mixtures.

  11. Excess Molar Volume and Apparent Molar Volume of Binary Mixtures of 2—Methyl—3—buten—2—ol with 1—Alcohol at 298.15K

    Institute of Scientific and Technical Information of China (English)

    LIUDixia; LIHaoran; 等

    2002-01-01

    Excess molar volumes (VmE) of binary mixtures of 2-methyl-3-buten-2-ol[CH3C(OH)(CH3)CHCH2] with four 1-alcohols:methanol,ethanol,1-propanol and 1-butanol at 298.15K and atmospheric pressure are derived from density measurements with a vibrating-tube densimeter.All the excess volumes are negative in the systems over the entire composition range. The results are correlated with the Redlich-Kister equation.The effects of chain length of 1-alcohols on VmE are discussed.The apparent molar volumes of 2-methyl-3-buten-2-ol and 1-alcohols are calculated respectively.

  12. Chemical isomeric effects on propanol glassy structures

    CERN Document Server

    Cuello, G J; Bermejo, F J; Cabrillo, C

    2002-01-01

    We have studied the structure of both propanol isomers in their glassy and crystalline states by neutron diffraction. The glass-transition temperatures of 1- and 2-propanol are about 98 and 115 K, respectively and, surprisingly, even larger differences are observed for the melting temperatures of the stable crystals, which are 148 and 185 K, respectively. Their supercooled liquid phases show rather different relaxation spectra, 1-propanol manifesting strong deviations from Debye behavior, whereas 2-propanol shows a far weaker effect. We discuss the spectra obtained for the static structure factor and the static pair correlation function D(r). There is a noticeable difference in the position of the first sharp diffraction peak, which clearly indicates a density change, well correlated with the period of the intermolecular oscillations shown by D(r). (orig.)

  13. Retention of Halogenated Solutes on Stationary Phases Containing Heavy Atoms

    Directory of Open Access Journals (Sweden)

    Toshio Miwa

    2013-05-01

    Full Text Available To examine the effects of weak intermolecular interactions on solid-phase extraction (SPE and chromatographic separation, we synthesized some novel stationary phases with a heavy atom effect layer by immobilizing halogenated aromatic rings and hydroxyl groups onto the surface of a hydrophilic base polymer. Using SPE cartridges packed with the functionalized materials, we found that the heavy atom stationary phases could selectively retain halophenols in organic solvents, such as 1-propanol which blocks the hydrogen bonding, or acetonitrile which blocks the p-p interaction. The extraction efficiency of the materials toward the halophenols depended on the dipole moments of phenoxy groups present as functional groups. On the other hand, the extraction efficiency of solutes toward the functional group depended on their molar refractions, i.e., induced dipole moments. The retention of the solutes to the stationary phase ultimately depended on not only strong intermolecular interactions, but also the effects of weak interactions such as the dispersion force.

  14. Synthesis of a new cyclosporine-based stationary phase and separation behaviors toward aromatic positional isomers by high-performance liquid chromatography.

    Science.gov (United States)

    Liu, Wen-na; Fan, Jun; Lin, Chun; Zheng, Sheng-run; Zhang, Wei-guang

    2015-04-01

    A new cyclosporine-bonded stationary phase has been synthesized through the Staudinger reaction between azido cyclosporine A (CsA) and aminopropyl silica gel and applied in separations of six disubstituted aromatic analytes by high-performance liquid chromatography. For dimethyl phthalate, nitroaniline and chloronitrobenzene, their positional isomers were well-separated on this CsA stationary phase, in which the separation factor for m-/o-dimethyl phthalates was the biggest. For nitrotoluene, dichlorobenzene and benzenediol, the m-/o-isomers were co-eluted. Then, effects of chromatographic conditions (such as types and content of alcoholic modifiers) on separation of nitroaniline positional isomers have been investigated. Retention behaviors of nitroaniline isomers on the column exhibited the strengthening trend along with increasing carbon number of alcohols, from ethanol to 1-propanol, and to 1-butanol. A similar phenomenon was observed by lowering the content of alcohol.

  15. Modeling and simulation of membrane separation process using computational fluid dynamics

    Directory of Open Access Journals (Sweden)

    Kambiz Tahvildari

    2016-01-01

    Full Text Available Separation of CO2 from air was simulated in this work. The considered process for removal of CO2 was a hollow-fiber membrane contactor and an aqueous solution of 2-amino-2-metyl-1-propanol (AMP as absorbent. The model was developed based on mass transfer as well as chemical reaction for CO2 and solvent in the contactor. The equations of model were solved using finite element method. Simulation results were compared with experimental data, and good agreement was observed. The results revealed that increasing solvent velocity enhances removal of CO2 in the hollow-fiber membrane contactor. Moreover, it was found that counter-current process mode is more favorable to achieve the highest separation efficiency.

  16. The Simulation of High Pressure Nucleation Experiments in Diffusion Cloud Chamber

    CERN Document Server

    Fisenko, Sergey P

    2007-01-01

    For high- pressure nucleation experiments in upward diffusion cloud chamber, there is the great deviation of predictions of classical nucleation theory from experimental results; the discrepancy is more than 10 orders of magnitude of nucleation rate. Experimental data for 1-propanol vapor are under investigation in this paper. It was shown that mathematical model of a single droplet growth and motion semi- quantitatively explained all experimentally discovered regularities. For explanations low nucleation rate versus high supersaturation, the coalescence mechanism in gaseous phase has been proposed. As result of coalescence the vast majority of newly formed clusters evaporate and restore vapor density and temperature profile in DCC. The observed picture with low nucleation rate is result of diffusion interaction between small clusters and droplets in nucleation zone for high- pressure nucleation experiments.

  17. Composição físico-química do vinho Bordô de Flores da Cunha, RS, elaborado com uvas maturadas em condições de baixa precipitação Physicochemical composition of Bordô wines from Flores da Cunha, RS, made with grapes matured in low rain conditions

    Directory of Open Access Journals (Sweden)

    Francine Maria Tecchio

    2007-10-01

    Full Text Available O Bordô é, depois do Isabel, o vinho de mesa de maior importância econômica na Serra Gaúcha, pois existe um considerável segmento de mercado que o aprecia, especialmente por seu sabor frutado e por sua cor intensa e matiz violeta. Devido a isso e às condições de estiagem que ocorreram no verão de 2005, quando as chuvas corresponderam a 38% da normal climatológica, analisaram-se vinhos Bordô do município de Flores da Cunha, RS, um dos mais importantes produtores da Serra Gaúcha. Os vinhos analisados eram varietalmente puros e elaborados segundo a tecnologia de cada vinícola. Avaliaram-se 39 variáveis, das quais os resultados mais expressivos foram os seguintes: álcool 10,58% v/v; acidez total 91meq L-1; acidez volátil 7,3meq L-1; pH 3,21; extrato seco 24,24g L-1; açúcares redutores 2,90g L-1; extrato seco reduzido 22,34g L-1; cinzas 2,09g L-1; ácido tartárico 5,35g L-1; DO 420 0,480; DO 520 1,296; DO 620 0,184; taninos 1,41g L-1; antocianinas 778,8mg L-1; etanal 14,9mg L-1; acetato de etila 59,3mg L-1; metanol 290,9mg L-1; 1-propanol 24,9mg L-1; 2-metiL-1-propanol 40,6mg L-1; 2-metiL-1-butanol 45,9mg L-1; 3-metiL-1-butanol 149,1mg L-1; soma dos álcoois superiores 260,5mg L-1; e K 953mg L-1.The Bordô, after Isabel, is the table wine presenting the greater economic importance in the Serra Gaúcha region, because there is a segment of the market that likes its characteristics, specially its fruity flavor, color intensity, and violet hue. Due to these aspects and to the very dry climatic conditions in the 2005 summer, where rain represented 38% of the climatological normal, Bordô wines were analyzed from the commune of Flores da Cunha, RS, Brazil, one of the most important producers of the Serra Gaúcha region. Analyzed wines were varietal ones and made according to the technology of each winery. Thirty nine variables were evaluated and the average parameters of the most expressive ones were the following: alcohol 10.58% v

  18. Transition from van-der-Waals to H Bonds dominated Interaction in n-Propanol physisorbed on Graphite

    CERN Document Server

    Wolff, Matthias; Huber, Patrick; Knorr, Klaus; Volkmann, Ulrich G; 10.1103/PhysRevLett.106.156103

    2011-01-01

    Multilayer sorption isotherms of 1-propanol on graphite have been measured by means of high-resolution ellipsometry within the liquid regime of the adsorbed film for temperatures ranging from 180 to 260 K. In the first three monolayers the molecules are oriented parallel to the substrate and the growth is roughly consistent with the Frenkel-Halsey-Hill-model (FHH) that is obeyed in van-der-Waals systems on strong substrates. The condensation of the fourth and higher layers is delayed with respect to the FHH-model. The fourth layer is actually a bilayer. Furthermore there is indication of a wetting transition. The results are interpreted in terms of hydrogen-bridge bonding within and between the layers.

  19. 水杨酸苯酯与C4醇固液平衡测定与关联%Measurement and Correlation of Solid-Liquid Equilibria of Phenyl Salicylate with C4 Alcohols

    Institute of Scientific and Technical Information of China (English)

    魏东炜; 裴艳红; 张超; 闫峰

    2009-01-01

    In an equilibrium vessel, the solid-liquid equilibria (SLE) for three binary mixtures of phenyl salicylate with 1-butanol, 2-butanol, and 2-methyl-1-propanol, respectively, have been measured from 283.15 K to the melt-ing temperature of the solute using a method in which an excess amount of solute was equilibrated with the alcohol solution. The liquid concentrations of the investigated phenyl salicylate in the saturated solution were analyzed by UV spectrometry. Activity coefficients for phenyl salicylate have been calculated by means of the Wilson, NRTL, and UNIQUAC equations and with them were correlated solubility data that were compared with the experimental ones. The best correlation of the solubility data has been obtained by the Wilson equation by which the average root-mean-square deviation of temperature for the three systems is 1.03 K.

  20. SOLUBILITY PREDICTION OF SULFONAMIDES AT VARIOUS TEMPERATURES USING A SINGLE DETERMINATION

    Directory of Open Access Journals (Sweden)

    JALAL HANAEE

    2005-04-01

    Full Text Available Solubility of sulphamethoxazole, sulphisoxazole and sulphasalazine in six solvents namely water,methanol, ethanol, 1-propanol, acetone and chloroform were determined at 15, 25, 37 and 45 °C. Two models derived from the Hildebrand solubility approach are proposed for solubility prediction at different temperatures using a single determination. The experimental data of the present work as well as data gathered from the literature have been employed to investigate the accuracy and prediction capability of the proposed models. The overall percent deviations between the predicted and experimental values were 10.78 and 14.63% which were comparable to those of the classical two and three parameter models. The proposed models were much superior to the two pure predictive models i.e., the ones which do not require experimental solubility determination, as the overall percent deviations produced by the latter models were 150.09 and 161.00%.

  1. Prebiotic Oxidative Polymerization of 2,3 Dimercaptopropanol on the Surface of Iron(III) Hydroxide Oxide

    Science.gov (United States)

    Weber, Arthur L.

    1994-01-01

    The oxidation of 2,3-Dimercapto-1-propanol by ferric ions on the surface of iron (III) hydroxide oxide yielded polydisulfide polymers. This polymerization occured readily at low dithiol concentration under mild aqueous conditions. Polydisulfide polymers up to the 15-mer were synthesized from 1 mM dithiol in 5 ml water reacted with iron (III) hydroxide oxide (20 mg, 160 micro mole Fe) for 3 days under anaerobic conditions at 40 C and pH 4. About 91% of the dithiol was converted to short soluble oligomers and 9% to insoluble larger oligomers that were isolated with the mineral phase. Reactions at higher dithiol concentrations with the same ratio of dithiol to mineral gave a higher yield of the larger insoluble oligomers. The relationship of these results to prebiotic polymer synthesis will be discussed.

  2. Use of a flor velum yeast for modulating colour, ethanol and major aroma compound contents in red wine.

    Science.gov (United States)

    Moreno, Juan; Moreno-García, Jaime; López-Muñoz, Beatriz; Mauricio, Juan Carlos; García-Martínez, Teresa

    2016-12-15

    The most important and negative effect of the global warming for winemakers in warm and sunny regions is the observed lag between industrial and phenolic grape ripeness, so only it is possible to obtain an acceptable colour when the ethanol content of wine is high. By contrast, the actual market trends are to low ethanol content wines. Flor yeast growing a short time under velum conditions, decreases the ethanol and volatile acidity contents, has a favorable effect on the colour and astringency and significantly changes the wine content in 1-propanol, isobutanol, acetaldehyde, 1,1-diethoxiethane and ethyl lactate. The Principal Component Analysis of six enological parameters or five aroma compounds allows to classify the wines subjected to different velum formation conditions. The obtained results in two tasting sessions suggest that the flor yeast helps to modulate the ethanol, astringency and colour and supports a new biotechnological perspective for red winemakers. PMID:27451159

  3. Enantiomer Separation of α-Dimethyl Dicarboxylate Biphenyl and Related Biphenyl Compounds by Normal Phase HPLC on Polysaccharide Based Chiral Stationary Phases

    Institute of Scientific and Technical Information of China (English)

    LIU,Yue-Qi(刘月启); HAN,Xiao-Qian(韩小茜); Qi,Bang-Feng(齐邦峰); LIU,Chun-Hui(柳春辉); LI,Yong-Min(李永民); CHEN,Li-Ren(陈立仁)

    2002-01-01

    Cellulose tris(4-methylphenylcarbamate), amylose tris(3,5-dimethylpphenylcarbamate) and amylose tris (phenylcarbamate)were prepared by the method reported by Okamoto and were coated onto an aminopropylated mesoporous spherical silica gel. These final products were used as chiral stationary phases of high performance liquid chromatography for the eighteen structurally related biphenyl conmpounds. The resolution was made using normal-phase methodology with a mobile phase consisting of n-hexane-alcohol (ethanol, 1-propanol, 2-propanol or 1-butanol). The effects of various aliphatic alcohols in the mobile phase were studied. The structural features of the solutes that influence their k'were discussed. A dominant effect of trifluoroaetic acid on chiral separation of aacidicdic solutes was noted.

  4. Method for producing high surface area chromia materials for catalysis

    Science.gov (United States)

    Gash, Alexander E.; Satcher, Joe; Tillotson, Thomas; Hrubesh, Lawrence; Simpson, Randall

    2007-05-01

    Nanostructured chromium(III)-oxide-based materials using sol-gel processing and a synthetic route for producing such materials are disclosed herein. Monolithic aerogels and xerogels having surface areas between 150 m.sup.2/g and 520 m.sup.2/g have been produced. The synthetic method employs the use of stable and inexpensive hydrated-chromium(III) inorganic salts and common solvents such as water, ethanol, methanol, 1-propanol, t-butanol, 2-ethoxy ethanol, and ethylene glycol, DMSO, and dimethyl formamide. The synthesis involves the dissolution of the metal salt in a solvent followed by an addition of a proton scavenger, such as an epoxide, which induces gel formation in a timely manner. Both critical point (supercritical extraction) and atmospheric (low temperature evaporation) drying may be employed to produce monolithic aerogels and xerogels, respectively.

  5. Densities, excess molar volumes, speeds of sound and isothermal compressibilities for {l_brace}2-(2-hexyloxyethoxy)ethanol + n-alkanol{r_brace} systems at temperatures between (288.15 and 308.15) K

    Energy Technology Data Exchange (ETDEWEB)

    Pal, Amalendu [Department of Chemistry, Kurukshetra University, Kurukshetra 136 119 (India)], E-mail: palchem@sify.com; Gaba, Rekha [Department of Chemistry, Kurukshetra University, Kurukshetra 136 119 (India)

    2008-05-15

    The densities, {rho} and the speeds of sound, u, for {l_brace}2-(2-hexyloxyethoxy)ethanol (C{sub 6}E{sub 2}) + methanol, +1-propanol, +1-pentanol, and +1-heptanol{r_brace} have been measured as a function of composition using an Anton-Paar DSA 5000 densimeter at temperatures (288.15, 293.15, 298.15, 303.15, and 308.15) K and atmospheric pressure over the whole concentration range. The {rho} and u values were used to calculate excess molar volumes, V{sup E}, and excess molar isentropic compressibility, K{sub S,m}{sup E}, respectively. Also, thermal expansivity, {alpha}, partial molar volume, V-bar{sub i}, and partial molar volume of the components at infinite dilution, V-bar{sub i}{sup 0}, have been calculated. The variation of these properties with composition and temperature of the mixtures are discussed in terms of molecular interactions.

  6. Rapid preparation and characterization of methacrylate-based monoliths for chromatographic and electrophoretic separation.

    Science.gov (United States)

    Fan, Li-Qun; Zhang, Yu-Ping; Gong, Wen-Jun; Qu, Ling-Bo; Lee, Kwang-Pill

    2010-01-01

    Butyl-methacrylate-based porous monoliths were rapidly prepared in the fused-silica capillary with a 10-cm stripe of polyimide removed from its exterior. The photopolymerization could be carried out in 150 s using ethylene glycol dimethacrylate as a cross-linking agent; 1-propanol, 1,4-butanediol, and water as tri-porogenic solvents; and Irgacure 1800 as a photo-initiator. The effect of different morphologies on the efficiency and retention properties was investigated using pressure-assisted CEC (p-CEC), CEC, and low pressure-assisted liquid chromatography modes (LPLC). Baseline separation of the model analytes was respectively achieved including thiourea, toluene, naphthalene, and biphenyl with the lowest theoretical height up to 8.0 microm for thiourea in the mode of p-CEC. Furthermore, the influence of the tri-porogenic solvents on the morphology of methacrylate-based monoliths was systematically studied with mercury intrusion porosimetry and scanning electron microscopy. PMID:20515536

  7. Kinetics study of CO2 absorption in AMP and Piperazine solutions

    OpenAIRE

    Usman, Muhammad

    2012-01-01

    Kinetics of CO2 in AMP (2-amino 2-methyl 1-propanol) with concentration of 0.1/0.5/1.0/2.0/3.0/4.0 M, 3M AMP with CO2 loadings of 0.15/0.22/0.29 and 0.1/0.5/1.0/1.5M piperazine solutions were measured at a temperature range of 25-70oC. The AMP system was measured at 1KPa pressure of CO2 while CO2- loaded AMP and piperazine were measured at different partial pressures that range from 1-9KPa. The experiments for AMP system were performed in string of disc contactor while PZ system was measured ...

  8. Henry’s constants and activity coefficients of some organic solutes in 1-butyl,3-methylimidazolium hydrogen sulfate and in 1-methyl,3-trimethylsilylmethylimidazolium chloride

    International Nuclear Information System (INIS)

    Highlights: ► New solubility data are reported for two ionic liquids. ► Density data are reported. ► Thermo-gravimetric analysis data are obtained. - Abstract: Using a customized capillary gas–liquid chromatography column, Henry’s constants and activity coefficients at infinite dilution are reported for benzene, toluene, ethyl acetate, 1,4-dioxane, 1,2-dimethoxyethane, acetonitrile, nitromethane, tetrahydrofuran, chloroform, methanol, ethanol, and 1-propanol in ionic liquids 1-butyl,3-methylimidazolium hydrogen sulfate [BMIM][HSO4] and 1-methyl,3-trimethylsilylmethylimidazolium [SiMIM][Cl] chloride from 313 to 413 K. These acidic ionic liquids may provide suitable media for acid-catalyzed chemical reactions.

  9. Capture of carbon dioxide by amine-impregnated as-synthesized MCM-41

    Institute of Scientific and Technical Information of China (English)

    Jianwen Wei; Lei Liao; Yu Xiao; Pei Zhang; Yao Shi

    2010-01-01

    The novel carbon dioxide (CO2) adsorbents with a high capture efficiency were prepared through impregnating the as-synthesized MCM-41 with three kinds of amines,namely diethylenetdamine (DETA),tdethylenetetramine (TETA) and 2-amino-2-methyl-1-propanol (AMP).The resultant samples were characterized by small angle X-ray diffraction and low temperature N2 adsorption.The synthesis way not only saves the energy or extractor to remove the template but also is environmentally friendly due to the absence of the potential pollutants such as toluene.CO2 capture was investigated in a dynamic packed column.The sample impregnated by TETA showed the highest adsorption capacity,approximately 2.22 mmol/g at 60℃ due to its highest amino-groups content among the three amines,The CO2 adsorption behavior was also investigated with the deactivation model,which showed an excellent prediction for the breakthrough curves.

  10. Standard Gibbs Energies of Transfer for KBPh4 from Water to Water+PrOH and Water+TBA Mixtures and the Primary Medium Effects

    Institute of Scientific and Technical Information of China (English)

    邹立壮; 王晓玲; 朱书全

    2002-01-01

    The standard Gibbs energies of transfer (ΔtrG0) for potassium tetraphenylborate (KBPh4) have been studied in the systems of water and water +1-propanol (PrOH) as well as water and water + t-b utyl alcohol (TBA) at 298.15*$K. The results show that -ΔtrG 0 exhibits a complicated changing pattern with the mole fraction of TBA(x (TBA)) or PrOH (x (PrOH)), and ΔtrG0 has the a m ax imum value at x (TBA) = 0.2 or x (PrOH)=0.2. Especially, -ΔtrG0 of KBPh4 changes unusually with increasing x (TBA) when x (TBA) < 0.05. The reasons for these changes were analyzed and discussed.

  11. Studies on the interactions of 2,5-diphenyl 1,3,4-oxadiazole and 2,5-diphenyl 1,3-oxazole with β-cyclodextrin

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Interactions of 2,5-diphenyl 1,3,4-oxadiazole (PPD) and 2,5-diphenyl 1,3-oxazole (PPO) with β-cyclodextrin (β-CD) are studied by 1H-NMR and steady-state fluorescence measurements, and the stoichiometries and the association constants are estimated. It is found that the hydrophobic interaction is the main driving force for the formation of inclusion complexes of PPD and PPO with β-CD. In the presence of aliphatic alcohols (from 1-propanol to 1-pentanol), PPD and PPO transfer from the CD cavity to the aqueous phase. Quenching experiments of PPD and PPO by iodide further prove the above conclusions. The results suggest that stereo effect is the crucial factor to the inexistence of nanotube in PPD (or PPO)-β-CD systems.

  12. Transition metal complexes of 5-bromosalicylidene-4-amino-3-mercapto-1,2,4-triazine-5-one: Synthesis, characterization, catalytic and antibacterial studies

    Directory of Open Access Journals (Sweden)

    AYALOOR SUBRAMANIAN RAMASUBRAMANIAN

    2011-01-01

    Full Text Available Transition metal complexes of 5-bromosalicylidene-4-amino-3-mercapto-1,2,4-triazine-5-one with metal precursors, such as Cu(II, Ni(II, Co(II and Pd(II, were synthesized and characterized by physico–chemical and spectroscopic techniques. All the complexes are of the ML type. Based on analytical, spectral data and magnetic moments, the Co(II and Ni(II complexes were assigned octahedral geometries, while the Cu (II and Pd(II complexes square planar. A study on the catalytic oxidation of benzyl alcohol, cyclohexanol, cinnamyl alcohol, 2-propanol and 2-methyl-1-propanol was performed with N-methylmorpholine-N-oxide (NMO as co-oxidant. All the complexes and their parent organic moiety were screened for their biological activity on several pathogenic bacteria and were found to possess appreciable bactericidal properties.

  13. Influence of cyclodextrin on the UCST- and LCST-behavior of poly(2-methacrylamido-caprolactam-co-(N,N-dimethylacrylamide

    Directory of Open Access Journals (Sweden)

    Alexander Burkhart

    2014-08-01

    Full Text Available The monomer 2-methacrylamido-caprolactam (4 was synthesized from methacryloyl chloride (3 and racemic α-amino-ε-caprolactam (2. Copolymerization of 4 with N,N-dimethylacrylamide (5 was carried out by a free-radical mechanism using 2,2’-azobis(2-methylpropionitrile (AIBN as an initiator. The new copolymers show a lower critical solution temperature (LCST in water and an upper critical solution temperature (UCST in ethanol, 1-propanol, and 1-butanol. The solubility properties of the copolymers can be influenced significantly by the addition of randomly methylated β-cyclodextrin (CD. The complexation of the copolymers with CD, was confirmed by the use of ROESY-NMR-spectroscopy.

  14. Measurements of Conductivity for Low Concentration Strong- electrolytes in Organic Solvents (I) LiBr, LiCI, and LiNO3 in Alcohols%Measurements of Conductivity for Low Concentration Strong- electrolytes in Organic Solvents (I) LiBr, LiCI, and LiNO3 in Alcohols

    Institute of Scientific and Technical Information of China (English)

    陈红; 王利生; 姜波; 李弥异

    2012-01-01

    The conductivities of LiBr, LiCl, and LiNO 3 in methanol, ethanol, 1-propanol, and 2-propanol (with electrolyte concentrations 〈0.08 mol·L-1 ) were determined at 298.15 K, 313.15 K, and 323.15 K at atmosphere pressure separately by using a conductivity meter. The conductivity data were correlated with Foss-Chen-Justice (FCJ) equation and the limiting molar conductivities were obtained. The mean ionic activity coefficients of the salts in the organic solvents were calculated according to the Debye-Hückel limiting law and Onsager-Falkenhangen equations. The calculated results were compared with those activity coefficients in literature.

  15. Synthesis of high refractive spiro heterocyclic derivatives through thioacetalization of multi-carbonyl compounds

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Jim Young; Maheswara, Muchchintala; Do, Jung Yun [Pusan National Univ., Busan (Korea, Republic of)

    2012-04-15

    Preparation of several new spirocyclic mercaptol derivatives is described. Thiol protection on multi-carbonyl compounds allows of high sulfur content necessary to induce high refractive index. Condensation of 1,3-dimercapto-2-propanol and cyclohexanone followed by successive oxidation and thioacetalization affords a dispiro cycle with four sulfurs. Selective S,S-protection of cyclohexane-1,4-dione is achieved with 1,3-dimercapto-2-propanol and 2,3-dimercapto-1-propanol to provide dispiro cycles with four sulfurs. Olefineoxidation of norbornene gives a useful dialdehyde intermediate which is transformed to 1,3-dithiolane for a linearly-bound-cyclic molecule. Refractive index of linearly-bound-cycles was below 1.60 and dispiro cycles exhibited high refractive index of 1.57-1.69.

  16. Effect of the composition of a water-alcohol solvent on the thermodynamics of dissolution of DL-α-alanyl-β-alanine at 298.15 K

    Science.gov (United States)

    Smirnov, V. I.; Badelin, V. G.

    2014-12-01

    Enthalpies of solution for DL-α-alanyl-β-alanine in H2O-ethanol, H2O-1-propanol, and H2O-2-propanol mixed solvents with the alcohol mole fraction x 2 = 0-0.3 are measured at 298.15 K. Standard enthalpies of solution (Δsol H ∘), standard enthalpies of transfer of DL-α-alanyl-β-alanine from water to binary solvent (Δtr H ∘), and coefficients of enthalpies of pair interactions with alcohol molecules ( h xy) are calculated. The effect the structure and properties of alcohols and the composition of a water-alcohol mixture have on the enthalpy of dissolution for DL-α-alanyl-β-alanine are discussed. The h xy values for dipeptides of the alanine series in water-alcohol binary solvents are compared.

  17. Effect of Initial Headspace O2 Level on the Growth and Volatile Metabolite Production of Leuconostoc Mesenteriodes and the Microbial and Sensorial Quality of Modified Atmosphere Packaged Par-Fried French Fries.

    Science.gov (United States)

    Samapundo, Simbarashe; Mujuru, Felix Mugove; de Baenst, Ilse; Denon, Quenten; Devlieghere, Frank

    2016-02-01

    This study evaluated the effect of residual O2 level (0% to 5%) on microbial growth and volatile metabolite production on par-fried French fries packaged in a modified atmosphere with 60% CO2 (rest N2 ) at 4 °C. The results obtained showed that the initial headspace (IH) O2 level had an effect on growth of Leuconostoc mesenteroides on French fry simulation agar, whereby growth was slightly faster under 5% O2 . In terms of quantity, ethanol, 2-methyl-1-propanol, and dimethyl disulphide were the most significant volatile metabolites produced by L. mesenteroides. The production of ethanol by L. mesenteroides was highest on simulation agar packaged under low IH O2 levels (0% to 1%), indicating that the fermentative metabolism was induced under these conditions. In agreement with the results observed on the simulation medium, growth of native lactic acid bacteria was faster under an IH O2 level of 5%. In addition, ethanol, 2-methyl-1-propanol, and dimethyl disulphide were also quantitatively the most important volatile metabolites. However, in contrast, greater quantities of ethanol and dimethyl disulphide were produced on par-fried French fries packaged under 5% O2 . This was attributed to the limited growth of the native flora on the par-fried French fries under residual O2 levels of 0% and 1%. Although some significant differences (P French fries packaged in 0%, 1%, and 5 % residual O2 during storage, all products were considered to be acceptable for consumption. The results of this study can be used to optimize the shelf-life of packaged chill stored potato products.

  18. Effects of solvent hydrogen bonding, viscosity, and polarity on the dispersion and alignment of nanofluids containing Fe2O3 nanoparticles

    Science.gov (United States)

    Christensen, Greg; Younes, Hammad; Hong, Haiping; Smith, Pauline

    2015-12-01

    It has been shown that the alignment of Iron (III) oxide (Fe2O3) nanoparticles in water (H2O) can enhance the thermal conductivity of nanofluids. To better understand solvent effects such as hydrogen bonding, viscosity, and polarity, nanofluids were prepared by mixing Fe2O3 nanoparticles and various solvents (water, ethanol, 1-propanol, isopropanol, 2-propanone, hexane, cyclohexane, ethylene glycol, glycerol, etc.), and the dispersions and alignments of the Fe2O3 nanoparticles in these solvents with and without an applied magnetic field were investigated using an optical microscope. The microscope images indicated that inter-molecule hydrogen bonding of the solvents with one OH group (water, ethanol, 1-propanol, and isopropanol) could help to disperse and align the Fe2O3 nanoparticles. The intra-molecular hydrogen bonding causes a dramatic increase in viscosity for fluids with multiple OH groups, such as ethylene glycol (C2H6O2) and glycerol (C3H8O3), and makes the Fe2O3 nanoparticles dispersion and alignment difficult. Adding water to those fluids could lead to significantly reduced viscosity and make the particles disperse and align well. Polarity studies indicated that higher polarity yields better dispersion and alignment of the Fe2O3 nanoparticles. Thermal studies showed that thermal conductivity of nanofluids containing metal oxide particles with hydrogen bonding in solvents is enhanced compared to the theoretically calculated data. Intermolecular hydrogen bonding between water and ethylene glycol increases the thermal conductivity of nanofluids while decreasing the fluid viscosity. The results also well explain why 50 wt. % water/50 wt. % ethylene glycol is an excellent commercial coolant. Since high thermal conductivity enhancement with minimal viscosity increase is the primary goal of heat transfer nanofluids, this current research may open new doors to better understanding of the fundamental nature of nanofluids.

  19. Conversion of 1,3-Propylene Glycol on Rutile TiO2(110)

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Long; Li, Zhenjun; Smith, R. Scott; Kay, Bruce D.; Dohnalek, Zdenek

    2014-10-09

    The adsorption of 1,3-propylene glycol (1,3-PG) on partially reduced TiO2(110) and its conversion to products have been studied by a combination of molecular beam dosing and temperature programmed desorption (TPD). When the Ti surface sites are saturated by 1,3-PG, ~80% of the molecules undergo further reactions to yield products that are liberated during the TPD ramp. In contrast to ethylene glycol (EG) and 1,2- propylene glycol (1,2-PG) that yield only alkenes and water at very low coverages (< 0.05 ML), two additional products, HCHO and C2H4, along with propylene (CH3CHCH2) and water are observed for 1,3-PG. Identical TPD line shapes and desorption yields for HCHO and C2H4 suggest that these products result from C-C bond cleavage and are coupled. At higher 1,3-PG coverages (> 0.1 ML), propanal (CH3CH2CHO) and two additional products, 1-propanol (CH3CH2CH2OH) and acrolein (CH2CHCHO), are observed. The desorption of 1-propanol is found to be coupled with the desorption of acrolein, suggesting that these products are formed by the disproportionation of two 1,3-PG molecules. The coverage dependent TPD results further show that propylene formation dominates at low coverages (< 0.3 ML), while the decomposition and disproportionation channels increase rapidly at higher coverages and reach yields comparable to that of propylene at the 1,3-PG saturation coverage of 0.5 ML. The observed surface chemistry clearly shows how the molecular structure of glycols influences their reaction pathways on oxide surfaces.

  20. Avaliação de mosto de uva fermentado Evaluation of fermented grape must

    Directory of Open Access Journals (Sweden)

    Maria Eugênia de Oliveira Mamede

    2007-06-01

    Full Text Available O objetivo deste estudo foi determinar a concentração de compostos voláteis nos mostos de uva Chardonnay e Pinot Noir fermentados pela Pichia membranaefaciens, como também analisar as fases de crescimento da levedura durante a fermentação a 15 e 20 °C. Compostos voláteis majoritários da fermentação como: etanol, acetato de etila, acetato de isoamila, acetaldeido, 1-propanol, isobutanol e álcool isoamílico foram isolados e quantificados pelo sistema de "Purge and Trap". A fermentação conduzida a 15 °C mostrou ser mais adequada na produção de acetato de etila, com valores inferiores a 200 mg.L-1 (131,3 e 147,0 mg.L-1 nos mostos Pinot Noir e Chardonnay, respectivamente, enquanto que a 20 °C a produção foi de 286,0 e 270,0 mg.L-1 nos mostos Pinot Noir e Chardonnay, respectivamente.The aim of this study was to determine the concentration of volatile compounds in Chardonnay and Pinot Noir grape musts. The study also aims to analyze yeast growth phases during fermentation at 15 and 20 °C. Major volatile compounds of fermentation such as ethanol, ethyl acetate, isoamyl acetate, acetaldehyde, 1-propanol, 3-methyl butanol and 2-methyl butanol were isolated and quantified using the Purge and Trap system. Fermentation carried out at 15 °C was more appropriate in the production of ethyl acetate (131.3 and 147.0 mg.L-1 in the Pinot Noir and Chardonnay musts, respectively, whilst at 20 °C the production was of 286.0 and 270.0 mg.L-1 in the Pinot Noir and Chardonnay musts respectively.

  1. Inactivation of murine norovirus by chemical biocides on stainless steel

    Directory of Open Access Journals (Sweden)

    Steinmann Jörg

    2009-07-01

    Full Text Available Abstract Background Human norovirus (NoV causes more than 80% of nonbacterial gastroenteritis in Europe and the United States. NoV transmission via contaminated surfaces may be significant for the spread of viruses. Therefore, measures for prevention and control, such as surface disinfection, are necessary to interrupt the dissemination of human NoV. Murine norovirus (MNV as a surrogate for human NoV was used to study the efficacy of active ingredients of chemical disinfectants for virus inactivation on inanimate surfaces. Methods The inactivating properties of different chemical biocides were tested in a quantitative carrier test with stainless steel discs without mechanical action. Vacuum-dried MNV was exposed to different concentrations of alcohols, peracetic acid (PAA or glutaraldehyde (GDA for 5 minutes exposure time. Detection of residual virus was determined by endpoint-titration on RAW 264.7 cells. Results PAA [1000 ppm], GDA [2500 ppm], ethanol [50% (v/v] and 1-propanol [30% (v/v] were able to inactivate MNV under clean conditions (0.03% BSA on the carriers by ≥ 4 log10 within 5 minutes exposure time, whereas 2-propanol showed a reduced effectiveness even at 60% (v/v. Furthermore, there were no significant differences in virus reduction whatever interfering substances were used. When testing with ethanol, 1- and 2-propanol, results under clean conditions were nearly the same as in the presence of dirty conditions (0.3% BSA plus 0.3% erythrocytes. Conclusion Products based upon PAA, GDA, ethanol and 1-propanol should be used for NoV inactivation on inanimate surfaces. Our data provide valuable information for the development of strategies to control NoV transmission via surfaces.

  2. Studies of solvent effects on reaction dynamics using ultrafast transient absorption spectroscopy

    Science.gov (United States)

    Harris, Don Ahmasi

    Ultrafast transient absorption spectroscopy was used to investigate the solvent dependent reaction dynamics of two prototypical chemical systems: (1) The ring-opening reaction of 1,3-cyclohexadiene, the isolated chromophore in Provitamin D, and (2) The photolysis of various Vitamin B12 cofactors. We investigated the influence of solvent polarity on the ground state conformational relaxation of 1,3,5-cis hexatriene subsequent to the ring opening of 1,3-cyclohexadiene in methanol and 1-propanol solvents. Comparisons to the conformational relaxation in alkane solvents studied earlier demonstrated a surprising influence of solvent polarity on single bond isomerization. Temperature dependent transient absorption measurements were performed on 1,3,5-cis hexatriene in cyclohexane and 1-propanol to determine the effect of solvent polarity on the activation energy barrier for ground state single bond isomerization. These measurements conclude that the polar solvent lowers the energy barrier for single bond isomerization allowing conformational relaxation to proceed faster in alcohol solvents compared to alkane solvents. With no perceived polar transition state for single bond isomerization, this result disagrees with the conventional view of solvation and differentiates the single bond isomerization dynamics of polyenes from alkanes. Transient absorption spectroscopy was also utilized to study the solvent effects in the photolysis of various B12 cofactors in different environments. We investigated the solvent dependent photolysis of adenosylcobalamin, methylcobalamin, and cyanocobalamin in water and ethylene glycol as a function of solvent temperature. In comparing the radical cage escape of adenosylcobalamin and cyanocobalamin, we determined a larger than expected hydrodynamic radii for the diffusing radicals in water compared to ethylene glycol, thus making necessary a revised perspective of solvent interaction with the diffusing radical. In addition, we investigated the

  3. Isobutanol-methanol mixtures from synthesis gas. Quarterly technical progress report, 1 April--30 June 30 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-07-25

    A series of CuMgCeO{sub x} catalysts have been prepared by coprecipitating the corresponding metal nitrates with a mixed solution of potassium carbonate and potassium hydroxide. Kinetic studies of methanol and ethanol coupling reactions on K-Cu/MgO/CeO{sub 2} and MgO/CeO{sub 2} catalysts indicate that Cu enhances the rates of alcohol dehydrogenation. The cross-coupling reactions of acetaldehyde and {sup 13}C-labeled methanol produce singly-labeled propionaldehyde, suggesting that it forms by the condensation of acetaldehyde and a reactive intermediate derived from methanol. Isobutyraldehyde, a precursor to isobutanol, forms via the condensation of propionaldehyde and a reactive C{sub 1} intermediate resulting from methanol. CO{sub 2}, one of the reaction products, poisons both basic and metal sites on Ce-containing CuMgO{sub x} catalysts, resulting in decreases in the rates of both alcohol dehydrogenation (Cu sites) and chain-growth condensation reactions (basic sites). CO{sub 2} inhibits ethanol dehydrogenation on both low-Cu and high-Cu CuMgCeO{sub x} catalysts; however, CO{sub 2} has no effect on the activity of low-Cu Ce-free Cu-MgO{sub x} catalysts, suggesting that the Cu on CuMgCeO{sub x} catalysts is more likely to be oxidized by CO{sub 2} to Cu{sup +} species that can be subsequently stabilized by CeO{sub 2}. CO{sub 2} effects on high-pressure isobutanol synthesis from CO/H{sub 2} have been studied on low- and high-Cu CuMgCeO{sub x} catalysts at 320{degrees}C and 4.5 MPa. CO{sub 2} addition and removal on low- and high-Cu catalysts show similar directional effects on CO conversion. CO conversion is lower at all space velocities in the presence of CO{sub 2}, and removal Of CO{sub 2} from the feed partially recovers CO conversion. CO{sub 2} decreases methanol and isobutanol productivities on both catalysts. Addition of 1-propanol to CO/H{sub 2} feed increases isobutanol production, suggesting that 1-propanol is a precursor to isobutanol.

  4. Identification of intact high molecular weight glutenin subunits from the wheat proteome using combined liquid chromatography-electrospray ionization mass spectrometry.

    Directory of Open Access Journals (Sweden)

    Bert Lagrain

    Full Text Available The present paper describes a method for the identification of intact high molecular weight glutenin subunits (HMW-GS, the quality determining proteins from the wheat storage proteome. The method includes isolation of HMW-GS from wheat flour, further separation of HMW-GS by reversed-phase high-performance liquid chromatography (RP-HPLC, and their subsequent molecular identification with electrospray ionization mass spectrometry using a quadrupole-time-of-flight mass analyzer. For HMW-GS isolation, wheat proteins were reduced and extracted from flour with 50% 1-propanol containing 1% dithiothreitol. HMW-GS were then selectively precipitated from the protein mixture by adjusting the 1-propanol concentration to 60%. The composition of the precipitated proteins was first evaluated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis with Coomassie staining and RP-HPLC with ultraviolet detection. Besides HMW-GS (≥65%, the isolated proteins mainly contained ω5-gliadins. Secondly, the isolated protein fraction was analyzed by liquid chromatography-mass spectrometry. Optimal chromatographic separation of HMW-GS from the other proteins in the isolated fraction was obtained when the mobile phase contained 0.1% trifluoroacetic acid as ion-pairing agent. Individual HMW-GS were then identified by determining their molecular masses from the high-resolution mass spectra and comparing these with theoretical masses calculated from amino acid sequences. Using formic acid instead of trifluoroacetic acid in the mobile phase increased protein peak intensities in the base peak mass chromatogram. This allowed the detection of even traces of other wheat proteins than HMW-GS in the isolated fraction, but the chromatographic separation was inferior with a major overlap between the elution ranges of HMW-GS and ω-gliadins. Overall, the described method allows a rapid assessment of wheat quality through the direct determination of the HMW-GS composition and

  5. Contribution of Liver Alcohol Dehydrogenase to Metabolism of Alcohols in Rats

    Science.gov (United States)

    Plapp, Bryce V.; Leidal, Kevin G.; Murch, Bruce P.; Green, David W.

    2015-01-01

    The kinetics of oxidation of various alcohols by purified rat liver alcohol dehydrogenase (ADH) were compared with the kinetics of elimination of the alcohols in rats in order to investigate the roles of ADH and other factors that contribute to the rates of metabolism of alcohols. Primary alcohols (ethanol, 1-propanol, 1-butanol, 2-methyl-1-propanol, 3-methyl-1-butanol) and diols (1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol) were eliminated in rats with zero-order kinetics at doses of 5–20 mmole/kg. Ethanol was eliminated most rapidly, at 7.9 mmole/kg•h. Secondary alcohols (2-propanol-d7, 2-propanol, 2-butanol, 3-pentanol, cyclopentanol, cyclohexanol) were eliminated with first order kinetics at doses of 5–10 mmole/kg, and the corresponding ketones were formed and slowly eliminated with zero or first order kinetics. The rates of elimination of various alcohols were inhibited on average 73% (55% for 2-propanol to 90% for ethanol) by 1 mmole/kg of 4-methylpyrazole, a good inhibitor of ADH, indicating a major role for ADH in the metabolism of the alcohols. The Michaelis kinetic constants from in vitro studies (pH 7.3, 37 °C) with isolated rat liver enzyme were used to calculate the expected relative rates of metabolism in rats. The rates of elimination generally increased with increased activity of ADH, but a maximum rate of 6 ± 1 mmole/kg•h was observed for the best substrates, suggesting that ADH activity is not solely rate-limiting. Because secondary alcohols only require one NAD+ for the conversion to ketones whereas primary alcohols require two equivalents of NAD+ for oxidation to the carboxylic acids, it appears that the rate of oxidation of NADH to NAD+ is not a major limiting factor for metabolism of these alcohols, but the rate-limiting factors are yet to be identified. PMID:25641189

  6. Enzymatic resolution of (R,S-ibuprofen and (R,S-ketoprofen by microbial lipases from native and commercial sources Resolução enzimática do (R,S-ibuprofeno e (R,S-cetoprofeno por lipases microbianas de fontes nativas e comerciais

    Directory of Open Access Journals (Sweden)

    Patrícia de Oliveira Carvalho

    2006-09-01

    Full Text Available The enantioselectivity (E of native lipases from Aspergillus niger, Aspergillus terreus, Fusarium oxysporum, Mucor javanicus, Penicillium solitum and Rhizopus javanicus in the resolution of (R,S-ibuprofen and (R,S-ketoprofenenantiomers by esterification reaction with 1-propanol in isooctane was compared with known commercial Candida rugosa (Sigma and Candida antarctica (Novozym®435 lipases. In the resolution of (R,S-ibuprofen, C. rugosa lipase showed good selectivity (E = 12 while Novozym®435 (E = 6.7 and A. niger (E = 4.8 lipases had intermediate selectivities. Other enzymes were much less selective (E around 2.3 and 1.5, under tested conditions. After preliminary optimization of reaction conditions (water content, enzyme concentration and presence of additives the enantioselectivity of native A. niger lipase could be enhanced substantially (E = 15. All tested lipases showed low selectivity in the resolution of (R,S-ketoprofen because poor ester yields and low enantiomeric excess of the acid remaining were achieved.A enantioseletividade (E das lipases nativas de Aspergillus niger, Aspergillus terreus, Fusarium oxysporum, Mucor javanicus, Penicillium solitum e Rhizopus javanicus na resolução dos enantiômeros do (R,S-ibuprofeno e (R,S-cetoprofeno na reação de esterificação com 1-propanol em isoctano foi comparada com as lipases comerciais de Candida rugosa (Sigma e Candida antarctica (Novozym®435. A lipase de C. rugosa mostrou boa enantioseletividade (E = 12 comparada com as da Novozym®435 (E = 6.7, de A. niger (E=4.8 e com as outras lipases que foram muito menos seletivas (E por volta de 2.3 e 1.5 na resolução do (R,S-ibuprofeno, dentro das condições testadas. Após uma otimização preliminar das condições da reação (conteúdo de água, concentração da enzima e presença de aditivos a enantioseletividade da lipase de A. niger pôde ser substancialmente aumentada (E = 15. Todas as lipases testadas mostraram baixa

  7. Study of surface tension and surface properties of binary systems of DMSO with long chain alcohols at various temperatures

    International Nuclear Information System (INIS)

    Highlights: • Surface tension of binary mixtures of alcohol/DMSO determined. • Surface mole fraction and surface thermodynamic parameters were calculated. • The surface tension data of binary mixtures were correlated with FLW, LWW and MS models. -- Abstract: Surface tensions of binary mixtures of DMSO (dimethyl sulphoxide) with a series of long chain aliphatic alcohols (1-propanol, 1-butanol, and 1-hexanol) were measured as a function of composition using the ring detachment method in the temperature range between (288.15 and 328.15) K. The surface tension results are used to describe quantitatively the nature, properties, and compositions of surface layers in binary liquid mixtures. The temperature influence on the behaviour of surface tensions and surface properties of binary mixtures has often been used to obtain information about solute structural effects on DMSO. The surface tension of the above mentioned binary systems were correlated with empirical and thermodynamic based models. The average relative error obtained from the comparison of experimental and calculated surface tension values for 15 binary systems with three models is less than 1%. In addition to finding more information about the surface structure of binary mixtures, surface mole fraction was calculated using an extended Langmuir model (EL). The temperature dependence of σ at fixed composition of solutions was used to estimate surface enthalpy, Hs, and surface entropy, Ss. The results provide information on the molecular interactions between the unlike molecules that exist at the surface and the bulk

  8. Enhancement of Lignin Biopolymer Isolation from Hybrid Poplar by Organosolv Pretreatments

    Directory of Open Access Journals (Sweden)

    Miao Wu

    2014-01-01

    Full Text Available Lignocellulosic biomass is an abundant renewable resource that has the potential to displace petroleum in the production of biomaterials and biofuels. In the present study, the fractionation of different lignin biopolymers from hybrid poplar based on organosolv pretreatments using 80% aqueous methanol, ethanol, 1-propanol, and 1-butanol at 220°C for 30 min was investigated. The isolated lignin fractions were characterized by Fourier transform infrared spectroscopy (FT-IR, high-performance anion exchange chromatography (HPAEC, 2D nuclear magnetic resonance (2D NMR, and thermogravimetric analysis (TGA. The results showed that the lignin fraction obtained with aqueous ethanol (EOL possessed the highest yield and the strongest thermal stability compared with other lignin fractions. In addition, other lignin fractions were almost absent of neutral sugars (1.16–1.46% though lignin preparation extracted with 1-butanol (BOL was incongruent (7.53%. 2D HSQC spectra analysis revealed that the four lignin fractions mainly consisted of β-O-4′ linkages combined with small amounts of β-β′ and β-5′ linkages. Furthermore, substitution of Cα in β-O-4′ substructures had occurred due to the effects of dissolvent during the autocatalyzed alcohol organosolv pretreatments. Therefore, aqueous ethanol was found to be the most promising alcoholic organic solvent compared with other alcohols to be used in noncatalyzed processes for the pretreatment of lignocellulosic biomass in biorefinery.

  9. The Amino Acid Specificity for Activation of Phenylalanine Hydroxylase Matches the Specificity for Stabilization of Regulatory Domain Dimers.

    Science.gov (United States)

    Zhang, Shengnan; Hinck, Andrew P; Fitzpatrick, Paul F

    2015-08-25

    Liver phenylalanine hydroxylase is allosterically activated by phenylalanine. The structural changes that accompany activation have not been identified, but recent studies of the effects of phenylalanine on the isolated regulatory domain of the enzyme support a model in which phenylalanine binding promotes regulatory domain dimerization. Such a model predicts that compounds that stabilize the regulatory domain dimer will also activate the enzyme. Nuclear magnetic resonance spectroscopy and analytical ultracentrifugation were used to determine the ability of different amino acids and phenylalanine analogues to stabilize the regulatory domain dimer. The abilities of these compounds to activate the enzyme were analyzed by measuring their effects on the fluorescence change that accompanies activation and on the activity directly. At concentrations of 10-50 mM, d-phenylalanine, l-methionine, l-norleucine, and (S)-2-amino-3-phenyl-1-propanol were able to activate the enzyme to the same extent as 1 mM l-phenylalanine. Lower levels of activation were seen with l-4-aminophenylalanine, l-leucine, l-isoleucine, and 3-phenylpropionate. The ability of these compounds to stabilize the regulatory domain dimer agreed with their ability to activate the enzyme. These results support a model in which allosteric activation of phenylalanine hydroxylase is linked to dimerization of regulatory domains.

  10. Alternative chromatographic system for the quality control of lipophilic technetium-99m radiopharmaceuticals such as [99mTc(MIBI6]+

    Directory of Open Access Journals (Sweden)

    D.P. Faria

    2015-01-01

    Full Text Available Knowledge of the radiochemical purity of radiopharmaceuticals is mandatory and can be evaluated by several methods and techniques. Planar chromatography is the technique normally employed in nuclear medicine since it is simple, rapid and usually of low cost. There is no standard system for the chromatographic technique, but price, separation efficiency and short time for execution must be considered. We have studied an alternative system using common chromatographic stationary phase and alcohol or alcohol:chloroform mixtures as the mobile phase, using the lipophilic radiopharmaceutical [99mTc(MIBI6]+ as a model. Whatman 1 modified phase paper and absolute ethanol, Whatman 1 paper and methanol:chloroform (25:75, Whatman 3MM paper and ethanol:chloroform (25:75, and the more expensive ITLC-SG and 1-propanol:chloroform (10:90 were suitable systems for the direct determination of radiochemical purity of [99mTc(MIBI6]+ since impurities such as 99mTc-reduced-hydrolyzed (RH, 99mTcO4 - and [99mTc(cysteine2]- complex were completely separated from the radiopharmaceutical, which moved toward the front of chromatographic systems while impurities were retained at the origin. The time required for analysis was 4 to 15 min, which is appropriate for nuclear medicine routines.

  11. Effect of water miscible organic solvents on p-nitrophenol hydroxylase (CYP2E1 activity in rat liver microsomes

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    Pranali G Patil

    2015-01-01

    Full Text Available Organic solvents used for solubilization of the substrates/NCEs are known to affect the activity of cytochrome P450 enzymes. Further, this effect varies with the solvents used, the substrates and CYP450 isoforms in question. In the present study, we have investigated the effect of ten commonly used water miscible organic solvents (methanol, ethanol, 1-propanol, 2-propanol, acetonitrile, acetone, dimethyl sulphoxide, N,N-dimethyl formamide, dioxane and polyethylene glycol 400 on p-nitrophenol hydroxylase activity at 0, 0.1, 0.25, 0.5, 0.75 and 1% v/v concentration in rat liver microsomes. All the solvents studied showed concentration dependent inhibition of the p-nitrophenol hydroxylase activity except acetonitrile which showed activation of the activity at concentration range studied. Out of ten solvents studied, dioxane was found to be the most inhibitory solvent (inhibition >90% at 0.25% v/v concentration. Overall, solvents like dimethyl sulphoxide, dimethyl formamide and dioxane appeared to be unsuitable for characterizing p-nitrophenol hydroxylase (CYP2E1-mediated reactions due to a high degree of inhibition. On the other hand, methanol and acetonitrile at concentrations <0.5% v/v appeared to be appropriate solvents for substrate solubilization while evaluating CYP2E1-mediated catalysis. The results of this study imply that caution should be exercised while choosing solvents for dissolution of substrate during enzyme studies in liver microsomes.

  12. Prepared polymethacrylate-based monoliths for the separation of cations by non-suppressed capillary ion chromatography.

    Science.gov (United States)

    Li, Jing; Zhu, Yan

    2014-01-01

    This paper describes a novel analytical system for non-suppressed capillary ion chromatography. Methacrylate monolithic columns were prepared from silanized fused-silica capillaries of 320 µm i.d. by in situ polymerization of glycidyl methacrylate and ethylene dimethacrylate in the presence of 1,4-butanediol, 1-propanol and water as the porogen solvents. The introduction of cation-exchange sites was achieved by sulfonating the matrix with sodium sulfite to produce total cation-exchange capacities in the range of 45-105 μequiv/mL for a 25 cm column. The conditions (concentrations of sodium sulfite solution, reacting time and modified flow rate) of sulfonation were optimized. The hydrodynamic and chromatographic performances were estimated. Coupled with a conductivity detector, a capillary ion chromatography system was set up with the prepared column. Finally, the resultant column was used for the separations of five common univalent cations (Li(+), Na(+), NH4(+), K(+) and Cs(+)) using methanesulfonic acid as the eluent and four divalent cations (Mg(2+), Ca(2+), Sr(2+) and Ba(2+)) by non-suppressed capillary ion chromatography; the chromatographic parameters were further researched.

  13. Lipid substrate specificity of phosphatidylethanolamine N-methyltransferase of Tetrahymena

    International Nuclear Information System (INIS)

    The ciliate protozoan Tetrahymena thermophila forms about 60% of its phosphatidylcholine by methylation of phosphatidylethanolamine with S-adenosylmethionine using the enzyme phosphatidylethanolamine N-methyltransferase. Analogues of ethanolamine or of ethanolamine phosphate are incorporated into the phospholipids of Tetrahymena when cells are cultured in their presence. These compounds, 3-amino-1-propanol, 2-aminoethylphosphonate, 3-aminopropylphosphonate and N,N-dimethylaminoethylphosphonate replace from 50 to 75% of the ethanolamine phosphate in phosphatidylethanolamine. However, analysis of the phospholipids of lipid-altered Tetrahymena showed that none of the phosphatidylethanolamine analogues had been converted to the corresponding phosphatidylcholine analogue. No incorration of [14C-CH3]methionine into the phosphatidylcholine analogues could be demonstrated in vivo, nor was label from [3H-CH3]S-adenosylmethionine incorporated in virto. Thus, only phosphatidylethanolamine and its monomethyl and dimethyl derivatives have been found to be substrates for the phosphatidylethanoiamine N-methyltransferase. The enzyme therefore requires a phospholipid substrate containing an ester linkage between the alkylamine and phosphorus, with the amino group required to be β to the alcohol

  14. Synthesis and characterization of a tetranuclear copper(Ⅱ) complex with a chiral Schiff base ligand

    Institute of Scientific and Technical Information of China (English)

    Hua Xiang; Long Jiang; Huan-Yong Li; Xiao-Dan Zheng; YU Li

    2013-01-01

    The title complex l-[CuⅡ4(Hvap)2(vap)2(MeOH)2](ClO4)2 1 has been synthesized and characterized by EA,IR,TGA,solid-state CD spectra and X-ray single-crystal analyses (I-H2vap:a Schiff base ligand derived from the condensation of o-vanillin and 1-2-amino-3-phenyl-1-propanol).Complex 1 crystallizes in monoclinic system,chiral space group P21 with a=10.4257(18),b=21.695(4),c=15.721(3) (A),β =94.443(3)°,V=3545.1 (11) (A)3,Z =2,Cu4C7oH78N4O22Cl2,Mr =1652.42,Dc =1.548 g/cm3,F(0 0 0) =1704 and μ(MoKα) =1.338 mm-1.The final R =0.0682 and wR =0.1420 for 6170 observed reflections with I > 2σ(Ⅰ) and R =0.1775 and wR =0.1830 for all data.The structure of complex 1 contains a boat-shaped {Cu4O4} motif.The solid-state CD spectra confirm the chiral nature of complex 1.

  15. Production of CaCO3/hyperbranched polyglycidol hybrid films using spray-coating technique.

    Science.gov (United States)

    Malinova, Kalina; Gunesch, Manfred; Montero Pancera, Sabrina; Wengeler, Robert; Rieger, Bernhard; Volkmer, Dirk

    2012-05-15

    Biomineralizing organisms employ macromolecules and cellular processing strategies in order to produce highly complex composite materials such as nacre. Bionic approaches translating this knowledge into viable technical production schemes for a large-scale production of biomimetic hybrid materials have met with limited success so far. Investigations presented here thus focus on the production of CaCO(3)/polymer hybrid coatings that can be applied to huge surface areas via reactive spray-coating. Technical requirements for simplicity and cost efficiency include a straightforward one-pot synthesis of low molecular weight hyperbranched polyglycidols (polyethers of 2,3-epoxy-1-propanol) as a simple mimic of biological macromolecules. Polymers functionalized with phosphate monoester, sulfate or carboxylate groups provide a means of controlling CaCO(3) particle density and morphology in the final coatings. We employ reactive spray-coating techniques to generate CaCO(3)/hybrid coatings among which vaterite composites can be prepared in the presence of sulfate-containing hyperbranched polyglycidol. These coatings show high stability and remained unchanged for periods longer than 9 months. By employing carboxylate-based hyperbranched polyglycidol, it is possible to deposit vaterite-calcite composites, whereas phosphate-ester-based hyperbranched polyglycidol leads to calcite composites. Nanoindentation was used to study mechanical properties, showing that coatings thus obtained are slightly harder than pure calcite. PMID:22386308

  16. Fluorescent-protein stabilization and high-resolution imaging of cleared, intact mouse brains.

    Directory of Open Access Journals (Sweden)

    Martin K Schwarz

    Full Text Available In order to observe and quantify long-range neuronal connections in intact mouse brain by light microscopy, it is first necessary to clear the brain, thus suppressing refractive-index variations. Here we describe a method that clears the brain and preserves the signal from proteinaceous fluorophores using a pH-adjusted non-aqueous index-matching medium. Successful clearing is enabled through the use of either 1-propanol or tert-butanol during dehydration whilst maintaining a basic pH. We show that high-resolution fluorescence imaging of entire, structurally intact juvenile and adult mouse brains is possible at subcellular resolution, even following many months in clearing solution. We also show that axonal long-range projections that are EGFP-labelled by modified Rabies virus can be imaged throughout the brain using a purpose-built light-sheet fluorescence microscope. To demonstrate the viability of the technique, we determined a detailed map of the monosynaptic projections onto a target cell population in the lateral entorhinal cortex. This example demonstrates that our method permits the quantification of whole-brain connectivity patterns at the subcellular level in the uncut brain.

  17. Effect of Agave tequilana age, cultivation field location and yeast strain on tequila fermentation process.

    Science.gov (United States)

    Pinal, L; Cornejo, E; Arellano, M; Herrera, E; Nuñez, L; Arrizon, J; Gschaedler, A

    2009-05-01

    The effect of yeast strain, the agave age and the cultivation field location of agave were evaluated using kinetic parameters and volatile compound production in the tequila fermentation process. Fermentations were carried out with Agave juice obtained from two cultivation fields (CF1 and CF2), as well as two ages (4 and 8 years) and two Saccharomyces cerevisiae yeast strains (GU3 and AR5) isolated from tequila fermentation must. Sugar consumption and ethanol production varied as a function of cultivation field and agave age. The production of ethyl acetate, 1-propanol, isobutanol and amyl alcohols were influenced in varying degrees by yeast strain, agave age and cultivation field. Methanol production was only affected by the agave age and 2-phenylethanol was influenced only by yeast strain. This work showed that the use of younger Agave tequilana for tequila fermentation resulted in differences in sugar consumption, ethanol and volatile compounds production at the end of fermentation, which could affect the sensory quality of the final product.

  18. Characterization of kinetic parameters and the formation of volatile compounds during the tequila fermentation by wild yeasts isolated from agave juice.

    Science.gov (United States)

    Arellano, Melchor; Pelayo, Carlos; Ramírez, Jesús; Rodriguez, Ingrid

    2008-08-01

    The production of aroma compounds during tequila fermentation using four native yeast strains isolated from agave juice was quantified at controlled (35 degrees C) and uncontrolled temperatures (room temperature) by gas chromatography (FID). Three of the four strains were identified as Saccharomyces cerevisiae (MTLI 1, MALI 1 and MGLI 1) and one as Kloeckera apiculata (MALI 2). Among the aroma compounds produced, acetaldehyde has the highest accumulation at the controlled temperature and before 50% of sugar was consumed. The S. cerevisiae strains produced ethyl acetate in almost the same quantity at a concentration of 5 mg/L and the K. apiculata produced six-times more (30 mg/L) than the S. cerevisiae strains, independent of the fermentation temperature. The rate and amount of 1-propanol, amyl alcohols and isobutanol production were affected by the type of yeast used. The K. apiculate strain produced 50% less of the higher alcohols than the Saccharomyces strains. The results obtained showed that indigenous isolated yeasts play an important role in the tequila flavor and suggest that mixtures of these yeasts may be used to produce tequila with a unique and desirable aroma.

  19. Ternary DNA chip based on a novel thymine spacer group chemistry.

    Science.gov (United States)

    Yang, Yanli; Yildiz, Umit Hakan; Peh, Jaime; Liedberg, Bo

    2015-01-01

    A novel thymine-based surface chemistry suitable for label-free electrochemical DNA detection is described. It involves a simple two-step sequential process: immobilization of 9-mer thymine-terminated probe DNAs followed by backfilling with 9-mer thymine-based spacers (T9). As compared to commonly used organic spacer groups like 2-mercaptoethanol, 3-mercapto-1-propanol and 6-mercapto-1-hexanol, the 9-mer thymine-based spacers offer a 10-fold improvement in discriminating between complementary and non-complementary target hybridization, which is due mainly to facilitated transport of the redox probes through the probe-DNA/T9 layers. Electrochemical measurements, complemented with Surface Plasmon Resonance (SPR) and Quartz Crystal Microbalance (QCM-D) binding analyses, reveal that optimum selectivity between complementary and non-complementary hybridization is obtained for a sensing surface prepared using probe-DNA and backfiller T9 at equimolar concentration (1:1). At this particular ratio, the probe-DNAs are preferentially oriented and easily accessible to yield a sensing surface with favorable hybridization and electron transfer characteristics. Our findings suggest that oligonucleotide-based spacer groups offer an attractive alternative to short organic thiol spacers in the design of future DNA biochips. PMID:25465760

  20. ZrO2 coatings on stainless steel by aerosol thermal spraying

    International Nuclear Information System (INIS)

    Zirconia coatings, with a wide range of thickness (1 to 80 μ) have been obtained by spraying a ZrO2 sol with an oxyacetylenic flame, on stainless steel substrates. The sol was prepared by mixing Zr-n-propoxide and acetic acid in order to obtain a zirconium oxyacetate precipitate, which was filtrated, washed with 1-propanol, dryed and subjected to an hydrothermal treatment. A new sol-gel based ceramic deposition process , aerosol thermal spraying was developed based on previous thermal spray work. A compressed air spray gun was used to produce a fine aerosol flow which was injected in the flame of the thermal spray torch and deposited on polished and sand blasted substrates. This original technique allows simultaneous spraying, drying and partial sintering of the zirconia nanometric particles. The maximum working temperature necessary to yield a resistant coating is 1000 deg C. This method produced crack-free homogeneous layers of monoclinic ZrO2 with good adhesion to the substrate and low porosity, as shown by X-ray diffraction and scanning electron microscopy. Oxidation test, carried out by heat treatments in air atmosphere at 800 deg C indicated good protection, mainly for low thickness coatings deposited in polished substrates. This original deposition technique offers several advantages when compared with classical thermal spraying techniques, such as plasma spraying. Copyright (1998) AD-TECH - International Foundation for the Advancement of Technology Ltd

  1. Molar excess enthalpies at T = 298.15 K for (1-alkanol + dibutylether) systems

    Energy Technology Data Exchange (ETDEWEB)

    Mozo, Ismael; Garcia De La Fuente, Isaias [G.E.T.E.F., Departamento de Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, 47071 Valladolid (Spain); Gonzalez, Juan Antonio, E-mail: jagl@termo.uva.e [G.E.T.E.F., Departamento de Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, 47071 Valladolid (Spain); Cobos, Jose Carlos [G.E.T.E.F., Departamento de Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, 47071 Valladolid (Spain)

    2010-01-15

    Molar excess enthalpies, H{sub m}{sup E}, at T = 298.15 K and atmospheric pressure have been measured using a microcalorimeter Tian-Calvet for the (methanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-octanol, or 1-decanol + dibutylether) systems. Experimental results have been compared with those obtained from the ERAS, DISQUAC, and Dortmund UNIFAC models. DISQUAC and ERAS yield similar H{sub m}{sup E}, results. Larger differences between experimental and calculated H{sub m}{sup E}, values are obtained from UNIFAC. ERAS represents quite accurately the excess molar volumes, V{sub m}{sup E}, of these systems. The excess molar internal energy at constant volume, U{sub V,m}{sup E}, is nearly constant for the solutions with the longer 1-alkanols. This points out that the different interactional contributions to this magnitude are counterbalanced. Interactions between unlike molecules are stronger in methanol systems. The same behaviour is observed in mixtures with dipropylether.

  2. Determination of alcohol compounds using corona discharge ion mobility spectrometry

    Institute of Scientific and Technical Information of China (English)

    HAN Hai-yan; HUANG Guo-dong; JIN Shun-ping; ZHENG Pei-chao; XU Guo-hua; LI Jian-quan; WANG Hong-mei; CHU Yan-nan

    2007-01-01

    Ion mobility spectrometry (IMS) is a very fast, highly sensitive, and inexpensive technique, it permits efficient monitoring of volatile organic compounds like alcohols. In this article, positive ion mobility spectra for six alcohol organic compounds have been systematically studied for the first time using a high-resolution IMS apparatus equipped with a discharge ionization source. Utilizing protonated water cluster ions (H2O)nH+ as the reactant ions and clean air as the drift gas, alcohol organic compounds, ethanol, 1-propanol, 2-propanol, 1-butanol, 1-pentanol and 2-octanol, all exhibit product ion characteristic peaks in their respective ion mobility spectrometry, that is a result of proton transfer reactions between the alcohols and reaction ions (H2O)nH+. The mixture of these alcohols, including two isomers, has been detected, and the result shows that they can also be distinguished effectively in the ion mobility spectrum. The reduced mobility values have been determined, which are in very well agreement with the traditional 63Ni-IMS experimental values. The exponential dilution method was used to calibrate the alcohol concentrations, and a detection limit available for the alcohols is in order of magnitude of a few ng/L.

  3. Thermodynamic properties of binary mixtures of 2,2,2-trifluoroethanol with water or alkanols at T=298.15K

    Energy Technology Data Exchange (ETDEWEB)

    Minamihonoki, Takashi [Graduate School of Science and Engineering, Tokyo Denki University, Hatoyama, Hiki-gun, Saitama 350-0394 (Japan)]. E-mail: taka-mi@m4.kcn.ne.jp; Ogawa, Hideo [Graduate School of Science and Engineering, Tokyo Denki University, Hatoyama, Hiki-gun, Saitama 350-0394 (Japan); Nomura, Hiroyasu [Graduate School of Science and Engineering, Tokyo Denki University, Hatoyama, Hiki-gun, Saitama 350-0394 (Japan); Murakami, Sachio [Frontier Research and Development Center, Tokyo Denki University, Hatoyama, Hiki-Gun, Saitama 350-0394 (Japan)

    2007-07-01

    Excess molar enthalpies (H{sub m}{sup E}) and excess molar volume (V{sub m}{sup E}) at T=298.15K for binary mixtures of {l_brace}2,2,2-trifluoroethanol (TFE)+water or alcohols (methanol, ethanol, 1-propanol){r_brace} were obtained by calorimetry and densimetry. Excess molar enthalpies for the (TFE+water) system showed endothermic mixing, except for the low TFE concentration range (x{sub 1}<0.1) in which they showed exothermic one. On the other hand, excess molar volumes for this system were negative over the whole range of concentration. Excess molar enthalpies for all the (TFE+alcohol) systems were exothermic over the whole range of concentration and decrease in absolute value with increase of the carbon number of the alkyl group in the alcohol molecules (n{sub C}). Excess molar volumes were positive over the whole range of concentration and increase with n{sub C}. Moreover, we estimated excess partial molar enthalpy (H{sub m,i}{sup E,{approx}}) and volume (V{sub m,i}{sup E,{approx}}) at infinite dilution from the experimental results. These results were discussed qualitatively from the viewpoint of the intermolecular interactions in the pure component liquids and the mixtures.

  4. Comparative studies on the alcohol types presence in Gracilaria sp. and rice fermentation using Sasad

    Science.gov (United States)

    Mansa, R.; Mansuit, H.; Sipaut, C. S.; Yee, C. F.; Yasir, S. M.

    2016-06-01

    Alternative fuel sources such as biofuels are needed in order to overcome environmental problem caused by fossil fuel consumption. Currently, most biofuel are produced from land based crops and there is a possibility that marine biomass such as macroalgae can be an alternative source for biofuel production. The carbohydrate in macroalgae can be broken down into simple sugar through thermo-chemical hydrolysis and enzymatic hydrolysis. Dilute-acid hydrolysis was believed to be the most available and affordable method. However, the process may release inhibitors which would affect alcohol yield from fermentation. Thus, this work was aimed at investigating if it is possible to avoid this critical pre-treatment step in macroalgae fermentation process by using Sasad, a local Sabahan fermentation agent and to compare the yield with rice wine fermentation. This work hoped to determine and compare the alcohol content from Gracilaria sp. and rice fermentation with Sasad. Rice fermentation was found containing ethanol and 2 - methyl - 1 - propanol. Fermentation of Gracilaria sp. had shown the positive presence of 3 - methyl - 1 - butanol. It was found that Sasad can be used as a fermentation agent for bioalcohol production from Gracilaria sp. without the need for a pretreatment step. However further investigations are needed to determine if pre-treatment would increase the yield of alcohol.

  5. Thermodynamic Properties of Transfer for Tetraphenylarsonium Tetraphylborate from Water to n-Alkanols

    Institute of Scientific and Technical Information of China (English)

    ZOU,Li-Zhuang(邹立壮); WANG,Xiao-Ling(王晓玲); ZHU,Shu-Quan(朱书全); WEI,Lu-Bin(韦鲁滨); LU,Yao(路遥); WANG,Jin-Ben(王金本)

    2002-01-01

    Solubilities of tetraphenylarsonium tetraphenyl,borate (Ph4AsBPh4) in water,methanol,ethanol,1-propanol,1-butanol,1-pentanol,1-hexanol and1-octanol at T=293.2,298.2,303.2 and 308.2 K have been determined by spectrophotometry.The standard transfer Gibbs energy(△trG0w→s)and entropy (△trS0w→s)of Ph4AsBPh4 from water to the n-alkanols at temerature from293.2 K to 308.2 K have been obtained.Fur thermore,the contribution of microscopic interactiou to the standard Gibbs energy if trabsfer for Pr4AsBPh4 was calculated and discussed.The results show that the effect of hydrophobic interaction of Ph4AsBPh4 on its transfer process is the mostimportant factor.According to the thermodynamical principle,thetransfer process of Ph4AsBPh4 from water to the n-alkanols is the entropy dominanted.

  6. Experiments on bifurcation of periodic states into tori for a periodically forced chemical oscillator

    Science.gov (United States)

    Vance, William; Ross, John

    1988-05-01

    We study experimentally continuous transitions from quasiperiodic to periodic states for a time-periodically forced chemical oscillator. The chemical reaction is the hydration of 2,3-epoxy-1-propanol, and is carried out in a continuous stirred tank reactor (CSTR). Periodic oscillatory states are observed to arise in the autonomous system through supercritical Hopf bifurcations as either the total flow rate or the cooling coil temperature is changed. Under conditions of oscillation for the autonomous system, small-amplitude periodic variation of the total flow rate generates an attracting two-torus from the stable limit cycle. From the experiments we determine the structure of the toroidal flow, stroboscopic phase portraits, and circle maps as a function of the forcing amplitude and period. A continuous transition from the quasiperiodic to a periodic state, in which the two-torus contracts to a closed curve (Neimark-Sacker torus bifurcation), is observed as the forcing amplitude is increased at a constant forcing period, or as the forcing period is changed at a constant moderate forcing amplitude. Qualitative theoretical predictions compare well with the experimental observations. This paper presents the first experimental observation of a Neimark-Sacker torus bifurcation in a forced chemical oscillator system, and relates the bifurcation diagram of the unforced system to that of the forced system.

  7. Laser spectroscopy and mass spectrometry of biologically relevant systems: chiral discrimination

    Science.gov (United States)

    Piccirillo, Susanna; Satta, Mauro; Coreno, Marcello; Catone, Daniele; Rondino, Flaminia; Scuderi, Debora; Paladini, Alessandra; Speranza, Maurizio; Giardini, Anna

    2005-06-01

    Radical ions are open-shell elusive species of paramount importance in many organic reactions and in biological processes. Oxidative bond breaking and forming involving radical ions are common process taking place in asymmetric enzyme cavities. Side-chain Cα-CΒ bond fragmentation in the radical cations of aromatic alcohols is a common process in solution [1-3], whose efficiency is enhanced in polar solvents such as water. Hydrogen-bonding between the ion and the solvent in the relevant transition structure is thought as responsible of the rate acceleration [4]. Effects of achiral and chiral microsolvation on the radical cation of R-(+)-l-phenyl-l-propanol, have been investigated. The energy thresholds of the homolytic Cα-Cβ bond breaking of R-(+)-1-phenyl-1-propanol radical cation, its mono-hydrated cluster, and its clusters with (2R,3R)-(-)-2,3-butanediol and (2S,3S)-(+)-2,3-butanediol have been studied through two color Resonant Two Photon Ionization, Photodissociation and Mass Spectrometry. The barrier of the Cα-Cβ fragmentation is appreciably higher for the unsolvated molecular ion than for its adducts with solvent molecules. Moreover, marked differences in the ethyl loss fragmentation energy are observed for the clusters with water and with the two diols. In particular the homochiral cluster with (2R, 3R)-(-)-2,3-butanediol exhibits a fragmentation barrier higher than that of the corresponding heterochiral adduct with (25, 35)-(+)-2,3-butanediol.

  8. The influence of clay on K{sub 2}CO{sub 3}/Co-MoS{sub 2} catalyst in the production of higher alcohol fuel

    Energy Technology Data Exchange (ETDEWEB)

    Iranmahboob, Jamshid; Nadim, Farhad [The Environmental Research Institute, University of Connecticut, Longley Building, 270 Middle Turnpike (Route 44) U-5210, 06269-5210 Storrs, CT (United States); Toghiani, Hossein; Hill, Donald O. [The Department of Chemical Engineering, Mississippi State University, Swalm Engineering Building, Room 330, Box 9595, 39762 Mississippi State, MS (United States)

    2002-08-20

    The K{sub 2}CO{sub 3}/Co-MoS{sub 2}/clay catalyst was synthesized and its productivity and selectivity toward higher alcohol synthesis (HAS) fuel were tested at temperature and pressure ranges of 290-320 C, H{sub 2}/CO=1.1 syngas, GHSV{sub avg}=1800 h{sup -1}, and 13790 kPa, respectively. Highest oxygenates productivity (0.32 kg/kg catalyst/h) was obtained at 310 C with an oxygenates selectivity of 70%. Under the above conditions, the major oxygenates produced were ethanol, 1-propanol, methanol, and isobutanol, respectively. Increasing the reaction temperature for K{sub 2}CO{sub 3}/Co-MoS{sub 2}/clay catalyst led to a decreasing trend in the selectivity of oxygenates. However, at higher temperatures, the clay-combined catalyst produced more hydrocarbons and CO{sub 2}. The results indicated that clay had a significant impact on higher alcohol synthesis when K{sub 2}CO{sub 3} was incorporated into the Co-MoS{sub 2}, and acted as a modifier of the catalyst serving to increase the activity and selectivity to higher alcohol fuel in the temperature range of 290-310 C.

  9. Isobutanol-methanol mixtures from synthesis gas. Quarterly technical progress report, 1 January--31 March 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-20

    A series of CuMgCeO{sub x} catalysts have been prepared. Range of Cu dispersion, determined by N{sub 2}O titration, was 19-48% and are among the highest reported in the literature for Cu-based methanol and higher alcohol synthesis catalysts. Kinetics of MeOH and EtOH coupling reactions on Cu/ZnO and K-Cu/MgO/CeO{sub 2} catalysts indicate that Cu promotes alcohol dehydrogenation. Acetaldehyde is a reactive intermediate. High-pressure isobutanol synthesis studies have been carried out on K- and Cs-promoted Cu/MgO/CeO{sub 2} catalysts. The K promoter is more active than Cs for CO conversion, but the Cs promoter activates the C{sub 1} to C{sub 2} step more effectively. Catalysts with high alkali loading resulted in low conversions. Temperature programmed surface reaction studies of MeOH, EtOH, and acetaldehyde on MgO/CeO{sub 2}-based Cu catalysts show evolution of acetone, crotonaldehyde, methyl ethyl ketone, H2, carbon oxides. Neither EtOH nor acetaldehyde produces propionaldehyde or 1- propanol, suggesting that these C{sub 3} species can only form via reactions involving C{sub 1} and C{sub 2} oxygenate species.

  10. Electron spin lattice relaxation of nitroxyl radicals in temperature ranges that span glassy solutions to low-viscosity liquids

    Science.gov (United States)

    Sato, Hideo; Bottle, Steven E.; Blinco, James P.; Micallef, Aaron S.; Eaton, Gareth R.; Eaton, Sandra S.

    2008-03-01

    Electron spin-lattice relaxation rates, 1/ T1, at X-band of nitroxyl radicals (4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl, 4-oxo-2,2,6,6-tetramethylpiperidin-1-oxyl, 3-carbamoyl-2,2,5,5-tetramethylpyrrolidin-1-oxyl and 3-carbamoyl-2,2,5,5-tetramethylpyrrolin-1-oxyl) in glass-forming solvents (decalin, glycerol, 3-methylpentane, o-terphenyl, 1-propanol, sorbitol, sucrose octaacetate, and 1:1 water:glycerol) at temperatures between 100 and 300 K were measured by long-pulse saturation recovery to investigate the relaxation processes in slow-to-fast tumbling regimes. A subset of samples was also studied at lower temperatures or at Q-band. Tumbling correlation times were calculated from continuous wave lineshapes. Temperature dependence and isotope substitution ( 2H and 15N) were used to distinguish the contributions of various processes. Below about 100 K relaxation is dominated by the Raman process. At higher temperatures, but below the glass transition temperature, a local mode process makes significant contributions. Above the glass transition temperature, increased rates of molecular tumbling modulate nuclear hyperfine and g anisotropy. The contribution from spin rotation is very small. Relaxation rates at X-band and Q-band are similar. The dependence of 1/ T1 on tumbling correlation times fits better with the Cole-Davidson spectral density function than with the Bloembergen-Purcell-Pound model.

  11. Comparisons of amine solvents for post-combustion CO{sub 2} capture: A multi-objective analysis approach

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Anita S; Eslick, John C; Miller, David C; Kitchin, John R

    2013-10-01

    Amine solvents are of great interest for post-combustion CO{sub 2} capture applications. Although the development of new solvents is predominantly conducted at the laboratory scale, the ability to assess the performance of newly developed solvents at the process scale is crucial to identifying the best solvents for CO{sub 2} capture. In this work we present a methodology to evaluate and objectively compare the process performance of different solvents. We use Aspen Plus, with the electrolyte-NRTL thermodynamic model for the solvent CO{sub 2} interactions, coupled with a multi-objective genetic algorithm optimization to determine the best process design and operating conditions for each solvent. This ensures that the processes utilized for the comparison are those which are best suited for the specific solvent. We evaluate and compare the process performance of monoethanolamine (MEA), diethanolamine (DEA), and 2-amino-2-methyl-1-propanol (AMP) in a 90% CO{sub 2} capture process from a 550 MW coal fired power plant. From our analysis the best process specifications are amine specific and with those specific, optimized specifications DEA has the potential to be a better performing solvent than MEA, with a lower energy penalty and lower capital cost investment.

  12. Application of integrated comprehensive/multidimensional gas chromatography with mass spectrometry and olfactometry for aroma analysis in wine and coffee.

    Science.gov (United States)

    Chin, Sung-Tong; Eyres, Graham T; Marriott, Philip J

    2015-10-15

    Component coelution in chromatographic analysis complicates identification and attribution of individual odour-active volatile molecules in complex multi-component samples. An integrated system incorporating comprehensive two-dimensional gas chromatography (GC × GC) and multidimensional gas chromatography (MDGC), with flame ionisation, olfactometry and mass spectrometry detection was developed to circumvent data correlation across different systems. Identification of potent odorants in Shiraz wine and the headspace of ground coffee are demonstrated as selected applications. Multiple solid-phase microextraction (SPME) sampling with GC-O located odour-active regions; GC × GC established the complexity of odour-active regions; MDGC provided high-resolution separation for each region; simultaneous 'O' and MS detection completed the analysis for target resolved peaks. Seven odour regions in Shiraz were analysed with MDGC-O/MS detection, revealing 11 odour volatiles through matching of mass spectrometry and retention indices from both separating dimensions, including acetic acid; octen-3-ol; ethyl octanoate; methyl-2-oxo-nonanoate; butanoic acid, 2-methylbutanoic acid, and 3-methylbutanoic acid; 3-(methylthio)-1-propanol; hexanoic acid; β-damascenone; and ethyl-3-phenylpropanoate. A capsicum odour in ground coffee was identified as 2-methoxy-3-isobutylpyrazine with a 5-fold increase in S/N of the odorant when acquired using a 6-time cumulative SPME sampling approach.

  13. Separation of Purine and Its Derivatives by Capillary Zone Electrophoresis

    Institute of Scientific and Technical Information of China (English)

    ZengBai-zhao; ZhaoFa-qiong

    2003-01-01

    The separation of a group of 17 purine and its derivatives by capillary zone electrophoresis is presented. A systematic approach was used to study the effect of pH, buffer type, organic modifiers, applied potential, sodium dodecyl sulfate (SDS) and cyclodextrins on the separation of these purine derivatives. An ideal condition was found for their separation, which was 30 mmol/L sodium borate buffer (pH 9-9.5), 10% (V/V) methanol buffer modifier and 20 kV. Under this condition, the 17 purine derivatives were baseline separated and the linear correlation coefficient for adenine,uric acid and 2-thioxanthine was 0. 99 over two orders of magnitude. The variation of peak areas was less than 4.6%(n= 5) and that of migration times was in the range of 0%-3%, while the samples were injected hydrodynamically at a height of 15 cm and an injection time of 8-10 s. In addition,alcohol, 1-propanol, 1-butanol and acetonitrile were also effective additives in the separation. However, SDS and various β-cyclodextrin (β-CDs) were found to do no good to their separation.

  14. Separation of Purine and Its Derivatives by Capillary Zone Electrophoresis

    Institute of Scientific and Technical Information of China (English)

    Zeng Bai-zhao; Zhao Fa-qiong

    2003-01-01

    The separation of a group of 17 purine and its derivatives by capillary zone electrophoresis is presented. A systematic approach was used to study the effect of pH, buff-er type, organic modifiers, applied potential, sodium dodecyl sulfate (SDS) and cyclodextrins on the separation of these pu-rine derivatives. An ideal condition was found for their se-paration, which was 30 mmol/L sodium borate buffer (pH 9-9.5), 10% (V/V) methanol buffer modifier and 20 kV. Un-der this condition, the 17 purine derivatives were baseline separated and the linear correlation coefficient for adenine,uric acid and 2-thioxanthine was 0. 99 over two orders of magnitude. The variation of peak areas was less than 4.6 %(n=5) and that of migration times was in the range of 0%-3%, while the samples were injected hydrodynamically at a height of 15 cm and an injection time of 8-10 s. In addition,alcohol, 1-propanol, 1-butanol and acetonitrile were also ef-fective additives in the separation. However, SDS and various β-cyclodextrin (β-CDs) were found to do no good to their se-paration.

  15. Application of the ERAS model to volumetric properties of binary mixtures of banana oil with primary and secondary alcohols (C1-C4) at different temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Behroozi, Mahboobe [Faculty of Chemistry, Bu-Ali Sina University, Hamedan (Iran, Islamic Republic of); Zarei, Hosseinali, E-mail: zareih@basu.ac.i [Faculty of Chemistry, Bu-Ali Sina University, Hamedan (Iran, Islamic Republic of)

    2011-05-15

    The densities of binary mixtures of {l_brace}isoamyl acetate + alcohols (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, and 2-butanol){r_brace}, including those of pure liquids, over the entire composition range were measured at temperatures (293.15 to 333.15) K and atmospheric pressure by means of a vibrating-tube densimeter. The excess molar volume, V{sub m}{sup E}, thermal expansion coefficients, {alpha}, and their excess values, {alpha}{sup E}, were calculated from density data. The V{sub m}{sup E} values are positive over the entire range of composition and temperature and become more positive with increasing temperature for all of the mixtures except for the (isoamyl acetate + methanol) mixture. The V{sub m}{sup E} values were correlated by Redlich-Kister equation and the extended real associated solution (ERAS) model was used for describing V{sub m}{sup E} values at T = 303.15 K.

  16. Alternative chromatographic system for the quality control of lipophilic technetium-99m radiopharmaceuticals such as [{sup 99m}Tc(MIBI){sub 6}]{sup +}

    Energy Technology Data Exchange (ETDEWEB)

    Faria, D.P.; Buchpiguel, C.A.; Marques, F.L.N., E-mail: danielefaria1@gmail.com [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Faculdade de Medicina. Departamento de Radiologia. Servico de Medicina Nuclear

    2015-10-15

    Knowledge of the radiochemical purity of radiopharmaceuticals is mandatory and can be evaluated by several methods and techniques. Planar chromatography is the technique normally employed in nuclear medicine since it is simple, rapid and usually of low cost. There is no standard system for the chromatographic technique, but price, separation efficiency and short time for execution must be considered. We have studied an alternative system using common chromatographic stationary phase and alcohol or alcohol:chloroform mixtures as the mobile phase, using the lipophilic radiopharmaceutical [{sup 99m}Tc(MIBI){sub 6}]{sup +} as a model. Whatman 1 modified phase paper and absolute ethanol, Whatman 1 paper and methanol: chloroform (25:75), Whatman 3MM paper and ethanol:chloroform (25:75), and the more expensive ITLC-SG and 1-propanol: chloroform (10:90) were suitable systems for the direct determination of radiochemical purity of [{sup 99m}Tc(MIBI){sub 6}]{sup +} since impurities such as {sup 99m}Tc-reduced-hydrolyzed (RH), {sup 99m}TcO4{sup -} and [{sup 99m}Tc(cysteine){sub 2}]{sup -} complex were completely separated from the radiopharmaceutical, which moved toward the front of chromatographic systems while impurities were retained at the origin. The time required for analysis was 4 to 15 min, which is appropriate for nuclear medicine routines. (author)

  17. Volatile compounds in whole meal bread crust: The effects of yeast level and fermentation temperature.

    Science.gov (United States)

    Nor Qhairul Izzreen, M N; Hansen, Se S; Petersen, Mikael A

    2016-11-01

    The influence of fermentation temperatures (8°C, 16°C, and 32°C) and yeast levels (2%, 4%, and 6% of the flour) on the formation of volatile compounds in the crust of whole meal wheat bread was investigated. The fermentation times were regulated to optimum bread height for each treatment. The volatile compounds were extracted by dynamic headspace extraction and analyzed by gas chromatography-mass spectrometry. The results were evaluated using multivariate data analysis and ANOVA. In all crust samples 28 volatile compounds out of 58 compounds were identified and the other 30 compounds were tentatively identified. Higher fermentation temperatures promoted the formation of Maillard reaction products 3-methyl-1-butanol, pyrazine, 2-ethylpyrazine, 2-ethyl-3-methylpyrazine, 2-vinylpyrazine, 3-hydroxy-2-butanone, 3-(methylsulfanyl)-propanal, and 5-methyl-2-furancarboxaldehyde whereas at lower temperature (8°C) the formation of 2- and 3-methylbutanal was favored. Higher levels of yeast promoted the formation of 3-methyl-1-butanol, 2-methyl-1-propanol and 3-(methylsulfanyl)-propanal, whereas hexanal was promoted in the crust fermented with lower yeast level. PMID:27211683

  18. Diffusion studies of dihydroxybenzene isomers in water-alcohol systems.

    Science.gov (United States)

    Codling, Dale J; Zheng, Gang; Stait-Gardner, Tim; Yang, Shu; Nilsson, Mathias; Price, William S

    2013-03-01

    Nuclear magnetic resonance diffusion studies can be used to identify different compounds in a mixture. However, because the diffusion coefficient is primarily dependent on the effective hydrodynamic radius, it is particularly difficult to resolve compounds with similar size and structure, such as isomers, on the basis of diffusion. Differential solution interactions between species in certain solutions can afford possibilities for separation. In the present study, the self-diffusion of the three isomers of dihydroxybenzene (i.e., (1,2-) catechol, (1,3-) resorcinol, and (1,4-) hydroquinone) was studied in water, aqueous monohydric alcohols (i.e., ethanol, 1-propanol, tert-butanol), and aqueous ethylene glycol. These systems allowed the effects of isomerism and differential solvent interactions on diffusion to be examined. It was found that, while in aqueous solution these isomers had the same diffusion coefficient, in water-monohydric alcohol systems the diffusion coefficient of catechol differed from those of resorcinol and hydroquinone. The separation was found to increase at higher concentrations of monohydric alcohols. The underlying chemical reasons for these differences were investigated.

  19. Role of α-Helical Structure in Organic Solvent-Activated Homodimer of Elastase Strain K

    Directory of Open Access Journals (Sweden)

    Chee Fah Wong

    2011-09-01

    Full Text Available Recombinant elastase strain K overexpressed from E. coli KRX/pCon2(3 was purified to homogeneity by a combination of hydrophobic interaction chromatography and ion exchange chromatography, with a final yield of 48% and a 25-fold increase in specific activity. The purified protein had exhibited a first ever reported homodimer size of 65 kDa by SDS-PAGE and MALDI-TOF, a size which is totally distinct from that of typically reported 33 kDa monomer from P. aeruginosa. The organic solvent stability experiment had demonstrated a stability pattern which completely opposed the rules laid out in previous reports in which activity stability and enhancement were observed in hydrophilic organic solvents such as DMSO, methanol, ethanol and 1-propanol. The high stability and enhancement of the enzyme in hydrophilic solvents were explained from the view of alteration in secondary structures. Elastinolytic activation and stability were observed in 25 and 50% of methanol, respectively, despite slight reduction in α-helical structure caused upon the addition of the solvent. Further characterization experiments had postulated great stability and enhancement of elastase strain K in broad range of temperatures, pHs, metal ions, surfactants, denaturing agents and substrate specificity, indicating its potential application in detergent formulation.

  20. Lipase-catalysed production of biodiesel fuel from some Nigerian lauric oils.

    Science.gov (United States)

    Abigor, R D; Uadia, P O; Foglia, T A; Haas, M J; Jones, K C; Okpefa, E; Obibuzor, J U; Bafor, M E

    2000-12-01

    Fatty acids esters were produced from two Nigerian lauric oils, palm kernel oil and coconut oil, by transesterification of the oils with different alcohols using PS30 lipase as a catalyst. In the conversion of palm kernel oil to alkyl esters (biodiesel), ethanol gave the highest conversion of 72%, t-butanol 62%, 1-butanol 42%, n-propanol 42% and iso-propanol 24%, while only 15% methyl ester was observed with methanol. With coconut oil, 1-butanol and iso-butanol achieved 40% conversion, 1-propanol 16% and ethanol 35%, while only traces of methyl esters were observed using methanol. Studies on some fuel properties of palm kernel oil and its biodiesel showed that palm kernel oil had a viscosity of 32.40 mm2/s, a cloud point of 28 degrees C and a pour point of 22 degrees C, while its biodiesel fuel had a viscosity of 9.33 mm2/s, a cloud point of 12 degrees C and a pour point of 8 degrees C. Coconut oil had a viscosity of 28.58 mm(2)/s, a cloud point of 27 degrees C and a pour point of 20 degrees C, while its biodiesel fuel had a viscosity of 7.34 mm2/s, a cloud point of 5 degrees C and a pour point of -8 degrees C. Some of the fuel properties compared favourably with international biodiesel specifications.

  1. Temperature dependence studies on the electro-oxidation of aliphatic alcohols with modified platinum electrodes

    Indian Academy of Sciences (India)

    Panadda Katikawong; Tanakorn Ratana; Waret Veerasai

    2009-05-01

    Temperature dependence on the electro-oxidation of methanol, ethanol and 1-propanol in 0.5 M H2SO4 were investigated with Pt and PtRu electrodes. Tafel slope and apparent activation energy were evaluated from the cyclic voltammetric data in the low potential region (0.3-0.5 V vs SHE). The CV results provided Tafel slopes for alcohols in the range of 200-400 mV dec-1 which indicated a difference in the rate determining step. The decrease in Tafel slope was only observed in the case of methanol for the Ru-modified Pt electrode. This indicates that Ru improves the rate of determining step for methanol while hindering it for the other alcohols. The electrochemical impedance spectroscopy was also used to evaluate the electro-oxidation mechanism of alcohols on these electrodes. The simulated EIS results provided two important parameters: charge transfer resistance () and inductance (). The $R^{-1}_{ct}$ and -1 represent the rate of alcohol electro-oxidation and rate of desorption of intermediate species, respectively. These values increased with the increasing of temperature. The results from two techniques were well agreed that the electro-oxidation of methanol was improved by raising the temperature and ruthenium modification.

  2. Inhibition of ceramide glucosylation sensitizes lung cancer cells to ABC294640, a first-in-class small molecule SphK2 inhibitor.

    Science.gov (United States)

    Guan, Shuhong; Liu, Yuan Y; Yan, Tingzan; Zhou, Jun

    2016-08-01

    Sphingosine kinase 2 (SphK2) is proposed as a novel oncotarget for lung cancer. Here, we studied the anti-lung cancer cell activity by ABC294640, a first-in-class SphK2 inhibitor. We showed that ABC294640 suppressed growth of primary and A549 human lung cancer cells, but sparing SphK2-low lung epithelial cells. Inhibition of SphK2 by ABC294640 increased ceramide accumulation, but decreased pro-survival sphingosine-1-phosphate (S1P) content, leading to lung cancer cell apoptosis activation. Significantly, we show that glucosylceramide synthase (GCS) might be a major resistance factor of ABC294640. The GCS inhibitor 1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP) or GCS shRNA/siRNA knockdown facilitated ABC294640-induced ceramide production and lung cancer cell apoptosis. Reversely, forced overexpression of GCS reduced ABC294640's sensitivity, resulting in decreased ceramide accumulation and apoptosis induction in A549 cells. These findings provide further evidences to support that targeting SphK2 by ABC294640 may be a rational treatment option for lung cancer. Ceramide glucosylation inhibition may further sensitize lung cancer cells to ABC294640. PMID:27221045

  3. Oxidation, Reduction, and Condensation of Alcohols over (MO3)3 (M=Mo, W) Nanoclusters

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Zongtang; Li, Zhenjun; Kelley, Matthew S.; Kay, Bruce D.; Li, Shenggang; Hennigan, Jamie M.; Rousseau, Roger J.; Dohnalek, Zdenek; Dixon, David A.

    2014-10-02

    The reactions of deuterated methanol, ethanol, 1-propanol, 1-butanol, 2-propanol, 2-butanol and t-butanol over cyclic (MO3)3 (M = Mo, W) clusters were studied experimentally with temperature programmed desorption (TPD) and theoretically with coupled cluster CCSD(T) theory and density functional theory. The reactions of two alcohols per M3O9 cluster are required to provide agreement with experiment for D2O release, dehydrogenation and dehydration. The reaction begins with the elimination of water by proton transfers and forms an intermediate dialkoxy species which can undergo further reaction. Dehydration proceeds by a β hydrogen transfer to a terminal M=O. Dehydrogenation takes place via an α hydrogen transfer to an adjacent MoVI = O atom or a WVI metal center with redox involved for M = Mo and no redox for M = W. The two channels have comparable activation energies. H/D exchange to produce alcohols can take place after olefin is released or via the dialkoxy species depending on the alcohol and the cluster. The Lewis acidity of the metal center with WVI being larger than MoVI results in the increased reactivity of W3O9 over Mo3O9 for dehydrogenation and dehydration.

  4. Phase behavior and second osmotic virial coefficient for competitive polymer solvation in mixed solvent solutions.

    Science.gov (United States)

    Dudowicz, Jacek; Freed, Karl F; Douglas, Jack F

    2015-11-21

    We apply our recently developed generalized Flory-Huggins (FH) type theory for the competitive solvation of polymers by two mixed solvents to explain general trends in the variation of phase boundaries and solvent quality (quantified by the second osmotic virial coefficient B2) with solvent composition. The complexity of the theoretically predicted miscibility patterns for these ternary mixtures arises from the competitive association between the polymer and the solvents and from the interplay of these associative interactions with the weak van der Waals interactions between all components of the mixture. The main focus here lies in determining the influence of the free energy parameters for polymer-solvent association (solvation) and the effective FH interaction parameters {χαβ} (driving phase separation) on the phase boundaries (specifically the spinodals), the second osmotic virial coefficient B2, and the relation between the positions of the spinodal curves and the theta temperatures at which B2 vanishes. Our classification of the predicted miscibility patterns is relevant to numerous applications of ternary polymer solutions in industrial formulations and the use of mixed solvent systems for polymer characterization, such as chromatographic separation where mixed solvents are commonly employed. A favorable comparison of B2 with experimental data for poly(methyl methacrylate)/acetonitrile/methanol (or 1-propanol) solutions only partially supports the validity of our theoretical predictions due to the lack of enough experimental data and the neglect of the self and mutual association of the solvents.

  5. Enzymes extracted from apple peels have activity in reducing higher alcohols in Chinese liquors.

    Science.gov (United States)

    Han, Qi'an; Shi, Junling; Zhu, Jing; Lv, Hongliang; Du, Shuangkui

    2014-10-01

    As the unavoidable byproducts of alcoholic fermentation, higher alcohols are unhealthy compounds widespread in alcoholic drinks. To investigate the activity of apple crude enzymes toward higher alcohols in liquors, five kinds of apple peels, namely, Fuji, Gala, Golden Delicious, Red Star, and Jonagold, were chosen to prepare enzymes, and three kinds of Chinese liquors, namely, Xifeng (containing 45% ethanol), Taibai (containing 50% ethanol), and Erguotou (containing 56% ethanol), were tested. Enzymes were prepared in the forms of liquid solution, powder, and immobilized enzymes using sodium alginate (SA) and chitosan. The treatment was carried out at 37 °C for 1 h. The relative amounts of different alcohols (including ethanol, 1-propanol, isobutanol, 1-butanol, isoamylol, and 1-hexanol) were measured using gas chromatography (GC). Conditions for preparing SA-immobilized Fuji enzymes (SA-IEP) were optimized, and the obtained SA-IEP (containing 0.3 g of enzyme) was continuously used to treat Xifeng liquor eight times, 20 mL per time. Significant degradation rates (DRs) of higher alcohols were observed at different degrees, and it also showed enzyme specificity according to the apple varieties and enzyme preparations. After five repeated treatments, the DRs of the optimized Fuji SA-IEP remained 70% for 1-hexanol and >15% for other higher alcohols.

  6. Simple cerium-triethanolamine complex: Synthesis, characterization, thermal decomposition and its application to prepare ceria support for platinum catalysts used in methane steam reforming

    Science.gov (United States)

    Wattanathana, Worawat; Nootsuwan, Nollapan; Veranitisagul, Chatchai; Koonsaeng, Nattamon; Laosiripojana, Navadol; Laobuthee, Apirat

    2015-06-01

    Cerium-triethanolamine complex was synthesized by simple complexation method in 1-propanol solvent using cerium(III) chloride as a metal source and triethanolamine as a ligand. The structures of the prepared complex were proposed based on FT-IR, FT-Raman and ESI-MS results as equimolar of triethanolamine and cerium chelated complex having monomeric tricyclic structure with and without chloride anion as another coordinating group known as ceratrane. The complex was used as a precursor for ceria material done by thermal decomposition. XRD result revealed that when calcined at 600 °C for 2 h, the cerium complex was totally turned into pure ceria with cubic fluorite structure. The obtained ceria was then employed to synthesize platinum doped ceria catalysts for methane steam reforming. Various amounts of platinum i.e. 1, 3, 5 and 10 mol percents were introduced on the ceria support by microwave-assisted wetness impregnation using ammonium tetrachloroplatinate(II). The platinum-impregnated ceria powders were subjected to calcination in 10% hydrogen/helium atmosphere at 500 °C for 3 h to reduce platinum(II) to platinum(0). XRD patterns of the catalysts confirmed that the platinum particles doped on the ceria support were in the form of platinum(0). Catalytic activity test showed that the catalytic activities got higher as the amounts of platinum doped increased. Besides, the portions of coke formation on the surface of catalysts were reduced as the amounts of platinum doped increased.

  7. Extraction and purification of anthraquinones derivatives from Aloe vera L. using alcohol/salt aqueous two-phase system.

    Science.gov (United States)

    Tan, Zhi-jian; Li, Fen-fang; Xu, Xue-lei

    2013-08-01

    An alcohol/salt aqueous two-phase system (ATPS) composed of 1-propanol and (NH4)2SO4 was employed to purify anthraquinones (AQs) extracted from Aloe vera L. The main influencing system parameters such as type of alcohol, type and concentration of salt, temperature and pH were investigated in detail. Under the optimal extraction conditions, AQs can be extracted into alcohol-rich phase with high extraction efficiency, meanwhile majority polysaccharides, proteins, mineral substances and other impurities were extracted into salt-rich phase. Partitioning of AQs is dependent on hydrophobic interaction, hydrogen bond interaction, and salting-out effect in ATPS. Temperature also played a great role in the partitioning. After ATPS extraction, alcohol can be recycled by evaporation; moreover, salt can be recycled by dilution crystallization method. Compared with other liquid-liquid extractions, this alcohol/salt system is much simpler, lower in cost with easier recovery of phase-forming components, which has the potential scale-up in down-processing of active ingredients in plant.

  8. A Comparative Study of Spin Coated Transparent Conducting Thin Films of Gallium and Aluminum Doped ZnO Nanoparticles

    Directory of Open Access Journals (Sweden)

    A. Alkahlout

    2015-01-01

    Full Text Available Transparent conducting Ga:ZnO (GZO and Al:ZnO (AZO layers have been deposited by spin coating on glass substrates using crystalline nanoparticles redispersed in 1-propanol. The coatings have been sintered in air at 600°C for 15 min and then postannealed in a reducing atmosphere at 400°C for 90 min. The effect of Ga and Al doping on the structural, morphological, optical, and electrical properties of the obtained thin films was investigated. Both films were found to be crystalline with a hexagonal structure. A single step spin coated layer 52–56 nm thick is obtained. To increase the thickness and lower the obtained sheet resistance multilayers coatings have been used. The visible transmission of both layers is high (T>80%. The influence of the sintering temperature and the optimum doping concentration was investigated. Five layers synthesized with doping ratio of 1 mol.% and sintered at 600°C and then submitted to reducing treatment in forming gas exhibited a minimum resistivity value of 7.4 × 10−2 Ω·cm for GZO layer and 1.45 Ω·cm for AZO coating.

  9. Adsorption and Reaction of C1-C3 Alcohols over CeOx(111) Thin Films

    Energy Technology Data Exchange (ETDEWEB)

    D Mullins; S Senanayake; T Chen

    2011-12-31

    This study reports the interaction of methanol, ethanol, 1-propanol, and 2-propanol with well-ordered CeO{sub 2}(111) thin film surfaces. All of the alcohols adsorb at low temperature by forming alkoxy and hydroxyl species on the surface. On fully oxidized CeO{sub 2}(111), recombination occurs between some of the alkoxys and hydroxyls, resulting in alcohol desorption near 220 K. At the same temperature, some of the surface hydroxyls disproportionate to produce water and the loss of lattice O. The remaining alkoxys react above 550 K. The primary alcohols favor dehydrogenation products (aldehydes). There is a net loss of O from the system, resulting in a reduction of the ceria. The secondary alcohol, 2-propanol, undergoes primarily dehydration, producing propene with no net change in the cerium oxidation state. Reduced CeO{sub x}(111) competes with the gaseous products for available O. Little or no water is produced. The reaction selectivity for the C{sub 2} and C{sub 3} alcohols shifts toward favoring dehydration products. The loss of O from the alcohols leads to oxidation of the reduced ceria. Compared with the oxidized surface, the alkene desorption shifts to lower temperature, whereas the aldehyde desorption shifts to higher temperature. This indicates that, on the reduced surface, it is easier to break the C-O bond but more difficult to break the O-substrate bond.

  10. Review of the Synthetic Methods for Antidepressants of Duloxetine%抗抑郁药度洛西汀的合成方法综述

    Institute of Scientific and Technical Information of China (English)

    杨爱平; 陈灿

    2012-01-01

    Duloxetine,an antidepressant,which is chemically stable,and has less side effects and better efficacy,has greater market prospects than other antidepressants in the treatment of depression.Several synthetic methods of duloxetine were presented in the paper,and their advantages and disadvantages were compared.The synthetic route that use(S)-3-(dimethylamino)-1-(2-thienyl)-1-propanol as raw materials,through split,etherification,esterification and hydrolysis to synthesis of duloxetine was the most competitive route.%抗抑郁药度洛西汀因其化学稳定、副作用小、药效明显优于其它抗抑郁药而具有广阔的发展前景,文章详细叙述了近年来国内外常见的几种合成方法,评述了各自优缺点,得出了一条最具竞争力的合成路线:以(S)-3-二甲胺基一1-2-噻吩基)-1-丙醇为原料,经拆分、醚化、酯化、水解得到目标。

  11. Protonation thermodynamics of some aminophenol derivatives in NaCl{sub (aq)} (0 {<=} I {<=}3 mol . kg{sup -1}) at T = 298.15 K

    Energy Technology Data Exchange (ETDEWEB)

    Bretti, Clemente; De Stefano, Concetta; Foti, Claudia [Dipartimento di Chimica Inorganica, Chimica Analitica e Chimica Fisica, Universita di Messina, Viale F. Stagno d' Alcontres, 31, I-98166 Messina (Vill. S. Agata) (Italy); Sammartano, Silvio, E-mail: ssammartano@unime.it [Dipartimento di Chimica Inorganica, Chimica Analitica e Chimica Fisica, Universita di Messina, Viale F. Stagno d' Alcontres, 31, I-98166 Messina (Vill. S. Agata) (Italy); Vianelli, Giuseppina [Dipartimento di Chimica Inorganica, Chimica Analitica e Chimica Fisica, Universita di Messina, Viale F. Stagno d' Alcontres, 31, I-98166 Messina (Vill. S. Agata) (Italy)

    2012-01-15

    Highlights: > Protonation thermodynamics of four aminophenol derivatives were determined. > Dependence on ionic strength was analysed by using different models. > Neutral species activity coefficient was determined by distribution measurements. > Acid-base behaviour of this ligand class was modelled. - Abstract: The acid-base properties of four aminophenol derivatives, namely m-aminophenol (L1), 4-amino-2-hydroxytoluene (L2), 2-amino-5-ethylphenol (L3) and 5-amino-4-chloro-o-cresol (L4), are studied by potentiometric and titration calorimetric measurements in NaCl{sub (aq)} (0 {<=} I {<=} 3 mol . kg{sup -1}) at T = 298.15 K. The dependence of the protonation constants on ionic strength is modelled by the Debye-Hueckel, SIT (Specific ion Interaction Theory) and Pitzer equations. Therefore, the values of protonation constants at infinite dilution and the relative interaction coefficients are calculated. The dependence of protonation enthalpies on ionic strength is also determined. Distribution (2-methyl-1-propanol/aqueous solution) measurements allowed us to determine the Setschenow coefficients and the activity coefficients of neutral species. Experimental results show that these compounds behave in a very similar way, and common class parameters are reported, in particular for the dependence on ionic strength of both protonation constants and protonation enthalpies.

  12. Evaluation of glycidyl methacrylate-based monolith functionalized with weak anion exchange moiety inside 0.5 mm i.d. column for liquid chromatographic separation of DNA

    Directory of Open Access Journals (Sweden)

    Aprilia Nur Tasfiyati

    2016-03-01

    Full Text Available In this study, the organic polymer monolith was developed as a weak anion exchanger column in high performance liquid chromatography for DNA separation. Methacrylate-based monolithic column was prepared in microbore silicosteel column (100 × 0.5 mm i.d. by in-situ polymerization reaction using glycidyl methacrylate as monomer; ethylene dimethacrylate as crosslinker; 1-propanol, 1,4-butanediol, and water as porogenic solvents, with the presence of initiator α,α′-azobisisobutyronitrile (AIBN. The monolith matrix was modified with diethylamine to create weak anion exchanger via ring opening reaction of epoxy groups. The morphology of the monolithic column was studied by SEM. The properties of the monolithic column, such as permeability, mechanical stability, binding capacity and pore size distribution, were characterized in detail. From the results of the characterization, monoliths poly-(GMA-co-EDMA with total monomer percentage (%T 40 and crosslinker percentage (%C 25 was found to be the ideal composition of monomer and crosslinker. It has good mechanical stability and high permeability, adequate molecular recognition sites (represented with binding capacity value of 36 mg ml−1, and has relatively equal proportion of flow-through pore and mesopores (37.2% and 41.1% respectively. Poly-(GMA-co-EDMA with %T 40 and %C 25 can successfully separate oligo(dT12–18 and 50 bp DNA ladder with good resolution.

  13. Influence of the Hydrothermal Method Growth Parameters on the Zinc Oxide Nanowires Deposited on Several Substrates

    Directory of Open Access Journals (Sweden)

    Concepción Mejía-García

    2014-01-01

    Full Text Available We report the synthesis of ZnO nanowires grown on several substrates (PET, glass, and Si using a two-step process: (a preparation of the seed layer on the substrate by spin coating, from solutions of zinc acetate dihydrate and 1-propanol, and (b growth of the ZnO nanostructures by dipping the substrate in an equimolar solution of zinc nitrate hexahydrate and hexamethylenetetramine. Subsequently, films were thermally treated with a commercial microwave oven (350 and 700 W for 5, 20, and 35 min. The ZnO nanowires obtained were characterized structurally, morphologically, and optically using XRD, SEM, and UV-VIS transmission, respectively. XRD patterns spectra revealed the presence of Zn(OH2 on the films grown on glass and Si substrates. A preferential orientation along c-axis directions for films grown on PET substrate was observed. An analysis by SEM revealed that the growth of the ZnO nanowires on PET and glass is better than the growth on Si when the same growth parameters are used. On glass substrates, ZnO nanowires less than 50 nm in diameter and between 200 nm and 1200 nm in length were obtained. The ZnO nanowires band gap energy for the films grown on PET and glass was obtained from optical transmission spectra.

  14. Proteinase-producing halophilic lactic acid bacteria isolated from fish sauce fermentation and their ability to produce volatile compounds.

    Science.gov (United States)

    Udomsil, Natteewan; Rodtong, Sureelak; Tanasupawat, Somboon; Yongsawatdigul, Jirawat

    2010-07-15

    Halophilic lactic acid bacteria were isolated from fish sauce mashes fermented at 1 to 12 months. Seven out of sixty-four isolates were selected according to their proteolytic activity and growth at 25% NaCl for characterization and investigation of volatile compound production. All selected isolates were Gram-positive cocci with pairs/tetrads and grew at 0-25% NaCl, pH 4.5-9.0. Results of 16S rRNA gene sequence analysis showed 99% homology to Tetragenococcus halophilus ATCC 33315. The restriction fragment length polymorphism (RFLP) patterns of all isolates were also similar to those of T. halophilus ATCC 33315. These isolates were, thus, identified as T. halophilus. All isolates hydrolyzed fish protein in the medium containing 25% NaCl. Intracellular aminopeptidase of 7 isolates exhibited the highest activity of 2.85-3.67 U/ml toward Ala-p-nitroanilide (Ala-pNA). T.halophilus strains MS33 and M11 showed the highest alanyl aminopeptidase activity (Phalophilus MS33 and MRC5-5-2 were 1-propanol, 2-methylpropanal, and benzaldehyde, corresponding to major volatile compounds in fish sauce. T.halophilus appeared to play an important role in volatile compound formation during fish sauce fermentation. PMID:20541276

  15. Osmotic coefficients and apparent molar volumes of 1-hexyl-3-methylimidazolium trifluoromethanesulfonate ionic liquid in alcohols

    International Nuclear Information System (INIS)

    Highlights: • Physical and osmotic properties of [HMim][TfO] in alcohols are reported. • Apparent molar properties and osmotic coefficients were obtained. • Apparent molar volumes were fitted using a Redlich–Meyer type equation. • The osmotic coefficients were modeled with the Extended Pitzer and the MNRTL models. -- Abstract: In this work, density for the binary mixtures of 1-hexyl-3-methylimidazolium trifluoromethanesulfonate in alcohols (1-propanol, or 2-propanol, or 1-butanol, or 2-butanol, or 1-pentanol) was measured at T = 323.15 K and atmospheric pressure. From this property, the corresponding apparent molar volumes were calculated and fitted to a Redlich–Meyer type equation. For these mixtures, the osmotic and activity coefficients, and vapor pressures of these binary systems were also determined at the same temperature using the vapor pressure osmometry technique. The experimental osmotic coefficients were modeled by the Extended Pitzer model of Archer. The parameters obtained in this correlation were used to calculate the mean molal activity coefficients and the excess Gibbs free energy for the studied mixtures

  16. Osmotic and apparent molar properties of binary mixtures alcohol + 1-butyl-3-methylimidazolium trifluoromethanesulfonate ionic liquid

    International Nuclear Information System (INIS)

    Highlights: ► Osmotic and physical properties of binary mixtures {alcohol + [BMim][TfO]} were measured. ► From experimental data, apparent molar properties and osmotic coefficients were calculated. ► The apparent properties were fitted using a Redlich–Meyer type equation. ► The osmotic coefficients were correlated using the Extended Pitzer model. -- Abstract: In this work, physical properties (densities and speeds of sound) for the binary systems {1-propanol, or 2-propanol, or 1-butanol, or 2-butanol, or 1-pentanol + 1-butyl-3-methylimidazolium trifluoromethanesulfonate} were experimentally measured from T = (293.15 to 323.15) K and at atmospheric pressure. These data were used to calculate the apparent molar volume and apparent molar isentropic compression which were fitted to a Redlich–Meyer type equation. This fit was used to obtain the corresponding apparent molar properties at infinite dilution. On the other hand, the osmotic and activity coefficients and vapor pressures of these binary mixtures were also determined at T = 323.15 K using the vapor pressure osmometry technique. The Extended Pitzer model of Archer was employed to correlate the experimental osmotic coefficients. From the parameters obtained in the correlation, the mean molal activity coefficients and the excess Gibbs free energy for the studied mixtures were calculated

  17. Separation and purification of glucosinolates from crude plant homogenates by high-speed counter-current chromatography.

    Science.gov (United States)

    Fahey, Jed W; Wade, Kristina L; Stephenson, Katherine K; Chou, F Edward

    2003-05-01

    Glucosinolates are anionic, hydrophilic plant secondary metabolites which are of particular interest due to their role in the prevention of cancer and other chronic and degenerative diseases. The separation and purification of glucosinolates from a variety of plant sources (e.g. seeds of broccoli, arugula and the horseradish tree), was achieved using high-speed counter-current chromatography (HSCCC). A high-salt, highly polar system containing 1-propanol-acetonitrile-saturated aqueous ammonium sulfate-water (1:0.5:1.2:1), was run on a semi-preparative scale and then transferred directly to preparative scale. Up to 7 g of a concentrated methanolic syrup containing about 10% glucosinolates was loaded on an 850-ml HSCCC column, and good separation and recovery were demonstrated for 4-methylsulfinylbutyl, 3-methylsulfinylpropyl, 4-methylthiobutyl, 2-propenyl and 4-(rhamnopyranosyloxy)benzyl glucosinolates. Multiple injections (5 to 6 times) were performed with well-preserved liquid stationary phase under centrifugal force. Pooled sequential runs with broccoli seed extract yielded about 20 g of its predominant glucosinolate, glucoraphanin, which was produced at > 95% purity and reduced to powdered form.

  18. Volumetric, acoustic, and viscometric studies of molecular interactions in binary mixtures of dipropylene glycol dimethyl ether with 1-alkanols at 298.15 K

    Energy Technology Data Exchange (ETDEWEB)

    Pal, Amalendu [Department of Chemistry, Kurukshetra University, Kurukshetra 136 119 (India)], E-mail: palchem@sify.com; Gaba, Rekha [Department of Chemistry, Kurukshetra University, Kurukshetra 136 119 (India)], E-mail: rekhagaba@gmail.com

    2008-05-15

    In this work densities, {rho}, ultrasonic speeds, u, and viscosities, {eta}, have been measured over the whole composition range for the binary mixtures of dipropylene glycol dimethyl ether (DPGDME) with ethanol, 1-propanol, 1-pentanol, and 1-heptanol at 298.15 K along with the properties of the pure components. By using the experimental values of {rho}, u, and {eta}, excess molar volume, V{sub m}{sup E}, deviations in viscosity, {delta}{eta}, excess free energy of activation for viscous flow, {delta}G*{sup E}, excess molar isentropic compressibility, K{sub S,m}{sup E}, deviation of the speeds of sound, u{sup D}, from their ideal values u{sup id} in an ideal mixtures, apparent molar volume, and apparent molar compressibility, V-bar{sub {phi}}{sub ,i}{sup 0} and K-bar{sub {phi}}{sub ,i}{sup 0} of the components at infinite dilution have been calculated. Finally, the experimental viscosity data have been correlated by the methods of Grunberg-Nissan, Hind, Tamura-Kurata, Chaudhry, Auslaender, Heric, and with McAllister correlations.

  19. Solvent sorting in (mixed solvent + electrolyte) systems: Time-resolved fluorescence measurements and theory

    Indian Academy of Sciences (India)

    Harun Al Rasidgazi; Hemant K Kashyap; Ranjit Biswas

    2015-01-01

    In this manuscriptwe explore electrolyte-induced modification of preferential solvation of a dipolar solute dissolved in a binary mixture of polar solvents. Composition dependence of solvation characteristics at a fixed electrolyte concentration has been followed. Binary mixtures of two different polarities have been employed to understand the competition between solute-ion and solute-solvent interactions. Time-resolved fluorescence Stokes shift and anisotropy have been measured for coumarin 153 (C153) in moderately polar (ethyl acetate + 1-propanol) and strongly polar (acetonitrile + propylene carbonate) binary mixtures at various mixture compositions, and in the corresponding 1.0M solutions of LiClO4. Both the mixtures show red shifts in C153 absorption and fluorescence emission upon increase of mole fraction of the less polar solvent component in presence of the electrolyte. In addition, measured average solvation times become slower and rotation times faster for the above change in the mixture composition. A semi-molecular theory based on solution density fluctuations has been developed and found to successfully capture the essential features of the measured Stokes shift dynamics of these complex multi-component mixtures. Dynamic anisotropy results have been analyzed by using both Stokes-Einstein-Debye (SED) and Dote-Kivelson-Schwartz (DKS) theories. The importance of local solvent structure around the dissolved solute has been stressed.

  20. From greenhouse gas to feedstock: formation of ammonium carbamate from CO{sub 2} and NH{sub 3} in organic solvents and its catalytic conversion into urea under mild conditions

    Energy Technology Data Exchange (ETDEWEB)

    Barzagli, F.; Mani, F.; Peruzzini, M. [University of Florence, Florence (Italy). Dept. of Chemistry

    2011-07-01

    The capture of carbon dioxide by ammonia in both aqueous and non-aqueous solutions was investigated at atmospheric pressure and 273 K under different operating conditions. The CO{sub 2} capture is fast and efficient ranging between 78 and 99%, depending on both the NH{sub 3} concentration and the solvent nature. The precipitation of solid mixtures of ammonium bicarbonate, ammonium carbonate and ammonium carbamate occurred in ethanol-water solution. Selective precipitation of ammonium carbamate was achieved by reacting gaseous CO{sub 2} and NH{sub 3} in anhydrous ethanol, 1-propanol or N,N-dimethylformamide (DMF) in a flow reactor that operates in continuous. In the second step of the process, the pure ammonium carbamate is used to produce urea with good yield (up to 54% on carbamate basis) at 393-413 K in the presence of inexpensive Cu(II) and Zn(II) catalysts. The yield of urea depends on several factors including the catalyst, the reaction temperature and the reaction time. Identification and quantification of urea in the reaction mixtures was obtained by analysis of its {sup 13}C NMR spectrum. A preliminary mechanistic interpretation of the catalytic reaction is also briefly presented and commented.

  1. Correlation of Chemical and Physical Test Data for the Environmental Ageing of Tefzel (ETFE). Revised

    Science.gov (United States)

    Morgan, G. J.; Campion, R. P.

    1997-01-01

    In a similar approach to that used for the previously issued correlation report for Coflon (CAPP/M.10), this report aims to identify any correlations between mechanical property changes and chemical/morphological changes for Tefzel, using information supplied in other MERL and TRI project reports. Differences identified with Coflon behaviour will be of scientific interest as well as appropriate to project applications, as Tefzel and Coflon are chemical isomers. Owing to the considerable chemical resistance of Tefzel, much of its testing so far has been based on mechanical properties. Where changes have occurred, chemical analysis can now be targeted more effectively. Relevant test data collated here include: tensile modulus and related properties, permeation coefficients, % crystallinity, some crack growth resistance measurements, and other observations where significant. Fluids based on methanol and amine (Fluid G), a mixture of methane, carbon dioxide and hydrogen sulphide gases plus an aqueous amine solution (Fluid F), and an aromatic oil mix of heptane, cyclohexane, toluene and 1-propanol (Fluid I) have affected Tefzel to varying degrees, and are discussed in some detail herein.

  2. Rapid and sensitive analysis of three polyphenols in tobacco by CE using homemade C(4)D with a mini detection cell.

    Science.gov (United States)

    Xie, Fuwei; Zhang, Yanhao; Zheng, Bo; Xu, Feifei; Su, Jianpo; Lu, Yanyan; Zeng, Fanya; Zhang, Bin; Guo, Yaxiao; Zhang, Shusheng

    2012-08-01

    A rapid, sensitive, and practical CE with C(4) D detection was developed for the analysis of three polyphenols (rutin, scopoletin, and chlorogenic acid) in tobacco samples. The constructed mini detection cell (12 mm × 10 mm × 10 mm) of C(4) D featured with small inner cell volume (∼2 nL), smaller noise (<0.9 mV), repeatability, high strength and durableness. Three polyphenols were ultrasonically extracted with methanol-water (70:30, v/v) solution following SPE cleanup. The CE method was optimized with the running buffer of 150 mmol L(-1) 2-amino-2-methyl-1-propanol (pH 11.2), and the applied separation voltage of +20 kV over a capillary of 50 μm id × 375 μm od × 50 cm (38 cm to the C(4) D window, 41.5 cm to the UV detector window), which gave a baseline separation of three polyphenols within ca. 6 min. The method provided the limits of quantification (S/N = 10) at about 0.08-0.15 μg g(-1) for three polyphenols, whereas the overall recoveries ranged from 82% to 88%. The proposed method has been successfully applied to measure three polyphenols in the actual tobacco samples, and their contents were calculated and evaluated. PMID:22887165

  3. Acid lipase from Candida viswanathii: production, biochemical properties, and potential application.

    Science.gov (United States)

    de Almeida, Alex Fernando; Tauk-Tornisielo, Sâmia Maria; Carmona, Eleonora Cano

    2013-01-01

    Influences of environmental variables and emulsifiers on lipase production of a Candida viswanathii strain were investigated. The highest lipase activity (101.1 U) was observed at 210 rpm, pH 6.0, and 27.5°C. Other fermentation parameters analyzed showed considerable rates of biomass yield (Y L/S = 1.381 g/g), lipase yield (Y L/S = 6.892 U/g), and biomass productivity (P X = 0.282 g/h). Addition of soybean lecithin increased lipase production in 1.45-fold, presenting lipase yield (Y L/S ) of 10.061 U/g. Crude lipase presented optimal activity at acid pH of 3.5, suggesting a new lipolytic enzyme for this genus and yeast in general. In addition, crude lipase presented high stability in acid conditions and temperature between 40 and 45°C, after 24 h of incubation in these temperatures. Lipase remained active in the presence of organic solvents maintaining above 80% activity in DMSO, methanol, acetonitrile, ethanol, acetone, 1-propanol, isopropanol, and 2-propanol. Effectiveness for the hydrolysis of a wide range of natural triglycerides suggests that this new acid lipase has high potential application in the oleochemical and food industries for hydrolysis and/or modification of triacylglycerols to improve the nutritional properties. PMID:24350270

  4. Production of CaCO3/hyperbranched polyglycidol hybrid films using spray-coating technique.

    Science.gov (United States)

    Malinova, Kalina; Gunesch, Manfred; Montero Pancera, Sabrina; Wengeler, Robert; Rieger, Bernhard; Volkmer, Dirk

    2012-05-15

    Biomineralizing organisms employ macromolecules and cellular processing strategies in order to produce highly complex composite materials such as nacre. Bionic approaches translating this knowledge into viable technical production schemes for a large-scale production of biomimetic hybrid materials have met with limited success so far. Investigations presented here thus focus on the production of CaCO(3)/polymer hybrid coatings that can be applied to huge surface areas via reactive spray-coating. Technical requirements for simplicity and cost efficiency include a straightforward one-pot synthesis of low molecular weight hyperbranched polyglycidols (polyethers of 2,3-epoxy-1-propanol) as a simple mimic of biological macromolecules. Polymers functionalized with phosphate monoester, sulfate or carboxylate groups provide a means of controlling CaCO(3) particle density and morphology in the final coatings. We employ reactive spray-coating techniques to generate CaCO(3)/hybrid coatings among which vaterite composites can be prepared in the presence of sulfate-containing hyperbranched polyglycidol. These coatings show high stability and remained unchanged for periods longer than 9 months. By employing carboxylate-based hyperbranched polyglycidol, it is possible to deposit vaterite-calcite composites, whereas phosphate-ester-based hyperbranched polyglycidol leads to calcite composites. Nanoindentation was used to study mechanical properties, showing that coatings thus obtained are slightly harder than pure calcite.

  5. Close correlation between heat shock response and cytotoxicity in Neurospora crassa treated with aliphatic alcohols and phenols

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, U.; Schweim, P.; Fracella, F.; Rensing, L. [Univ. of Bremen (Germany)

    1995-03-01

    In Neurospora crassa the aliphatic alcohols methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutanol, ethylene glycol, glycerol, and allyl alcohol and the phenolic compounds phenol, hydroquinone, resorcinol, pyrogallol, phloroglucinol, sodium salicylate, and acetylsalicylic acid were analyzed with respect to their capacities to induce heat shock proteins (HSP) and to inhibit protein synthesis. Both the alcohols and phenols showed the greatest levels of HSP induction at concentrations which inhibited the overall protein synthesis by about 50%. The abilities of the different alcohols to induce the heat shock response are proportional to their lipophilicities: the lipophilic alcohol isobutanol is maximally inductive at about 0.6 M, whereas the least lipophilic alcohol, methanol, causes maximal induction at 5.7 M. The phenols, in general, show a higher capability to induce the heat shock response. The concentrations for maximal induction range between 25 mM (sodium salicylate) and 100 mM (resorcinol). Glycerol (4.1 M) shifted the concentration necessary for maximal HSP induction by hydroquinone from 50 to 200 mM. The results reveal that the induction of HSP occurs under conditions which considerably constrain cell metabolism. The heat shock response, therefore, does not represent a sensitive marker for toxicity tests but provides a good estimate for the extent of cell damage.

  6. In vitro study on the disinfectability of two split-septum needle-free connection devices using different disinfection procedures

    Directory of Open Access Journals (Sweden)

    Engelhart, Steffen

    2015-12-01

    Full Text Available This in vitro study investigated the external disinfection of two needle-free connection devices (NFC using Octeniderm (spraying and wiping technique vs. Descoderm pads (wiping technique. The split-septum membrane of the NFC was contaminated with >10 CFU . The efficacy of the disinfection at 30 sec. exposure time was controlled by taking a swab sample and by flushing the NFC with sterile 0.9% sodium chloride solution. Disinfection with octenidine dihydrochloride 0.1 g, 1-Propanol 30.0 g, and 2-Propanol 45.0 g in solution was highly effective (CFU reduction ≥4 log against both microorganisms, whereas the use of 63.1 g 2-Propanol in 100 ml solution led to residual contamination with . Our investigation underlines that (i in clinical practice disinfection of NFCs before use is mandatory, and that (ii details of disinfection technique are of utmost importance regarding their efficacy. Our investigation revealed no significant differences between both split-septum NFC types. Clinical studies are needed to confirm a possible superiority of disinfectants with long-lasting residual antimicrobial activity.

  7. Use of micellar liquid chromatography to analyze oxolinic acid, flumequine, marbofloxacin and enrofloxacin in honey and validation according to the 2002/657/EC decision.

    Science.gov (United States)

    Tayeb-Cherif, K; Peris-Vicente, J; Carda-Broch, S; Esteve-Romero, J

    2016-07-01

    A micellar liquid chromatographic method was developed for the analysis of oxolinic acid, flumequine, marbofloxacin and enrofloxacin in honey. These quinolines are unethically used in beekeeping, and a zero-tolerance policy to antibiotic residues in honey has been stated by the European Union. The sample pretreatment was a 1:1 dilution with a 0.05M SDS at pH 3 solution, filtration and direct injection, thus avoiding extraction steps. The quinolones were eluted without interferences using mobile phase of 0.05M SDS/12.5% 1-propanol/0.5% triethylamine at pH 3, running at 1mL/min under isocratic room through a C18 column. The analytes were detected by fluorescence. The method was successfully validated according to the requirements of the European Union Decision 2002/657/EC in terms of: specificity, linearity (r(2)>0.995), limit of detection and decision limit (0.008-0.070mg/kg), lower limit of quantification (0.02-0.2mg/kg), detection capability (0.010-0.10mg/kg), recovery (82.1-110.0%), precision (honey supplied by a local supermarket, and the studied antibiotics were not detected. Therefore, the method was rapid, simple, safe, eco friendly, reliable and useful for the routine analysis of honey samples.

  8. Antimicrobial evaluation of selected naturally occurring oxyprenylated secondary metabolites.

    Science.gov (United States)

    Di Giulio, Mara; Genovese, Salvatore; Fiorito, Serena; Epifano, Francesco; Nostro, Antonia; Cellini, Luigina

    2016-08-01

    This study tested the antimicrobial activity of eight selected naturally occurring oxyprenylated secondary metabolites against Staphylococcus aureus ATCC 29213, S. epidermidis ATCC 35984, Escherichia coli ATCC 8739, Pseudomonas aeruginosa ATCC 9027 and Candida albicans ATCC 10231. Results showed a moderate antimicrobial activity. The most active compounds were 3-(4-geranyloxyphenyl)-1-ethanol (4) and 3-(4-isopentenyloxyphenyl)-1-propanol (5) that were tested on mature and in-formation biofilms of all micro-organisms, moreover the cytotoxic activity was evaluated. Except for S. epidermidis, both compounds reduced significantly (p biofilm formation at 1/2 MIC and 1/4 MIC, in particular, compounds 4 and 5 at each concentration, inhibited E. coli biofilm formation to a greater extent, the biofilm formation was never more than 44% in respect to the control, moreover both compounds showed a low cytotoxic effect. Oxyprenylated derivatives may be of great interest for the development of novel antimicrobial therapeutic strategies and the synthesis of semi-synthetic analogues with anti-biofilm efficacy. PMID:27498831

  9. Effects of Fermentation Temperature on Key Aroma Compounds and Sensory Properties of Apple Wine.

    Science.gov (United States)

    Peng, Bangzhu; Li, Fuling; Cui, Lu; Guo, Yaodong

    2015-12-01

    Fermentation temperature strongly affects yeast metabolism during apple wine making and thus aromatic and quality profiles. In this study, the temperature effect during apple wine making on both the key aroma compounds and sensory properties of apple wine were investigated. The concentration of nine key aroma compounds (ethyl acetate, isobutyl acetate, isopentylacetate, ethyl caprylate, ethyl 4-hydroxybutanoate, isobutylalcohol, isopentylalcohol, 3-methylthio-1-propanol, and benzeneethanol) in apple wine significantly increased with the increase of fermentation temperature from 17 to 20 °C, and then eight out of the nine key aroma compounds with an exception of ethyl 4-hydroxybutanoate, decreased when the temperature goes up 20 to 26 °C. Sensory analysis showed that the apple wine fermented at 20 °C had the highest acceptance for consumers. Fermentation at the temperature of 20 °C was therefore considered to be the most suitable condition using the selected yeast strain (Saccharomyces cerevisiae AP05) for apple wine making. Changes in the fermentation temperature can considerably affect the production of key aroma compounds and sensory profiles of apple wine. These results could help apple wine producers make better quality production for consumers at the optimal fermentation temperature.

  10. Plasma-polymerized films providing selective affinity to the polarity of vaporized organic solvents

    International Nuclear Information System (INIS)

    Plasma-polymerized films (PPFs) were fabricated as recognition membranes for a vapor-sensing device, and their affinity to vaporized organic solvents was evaluated with surface plasmon resonance. The affinity we intended to create is the selective sorption of the vaporized organic solvents depending on their polarity. For this purpose, acetonitrile, ethylenediamine (EDA), styrene, hexamethyldisiloxane (HMDSO), and hexamethyldisilazane were used to fabricate PPFs. Vaporized methanol, ethanol, and 1-propanol were used as high-polar solvents to be analyzed. Hexane, toluene, and p-xylene were used as low-polar solvents. As a result, the HMDSO-PPF with 97.3o of contact angle was found to provide affinity to the low-polar solvents. In contrast, the EDA-PPF with 7.1o of contact angle provided affinity to the high-polar solvents. Observations of the surface morphology of the HMDSO- and EDA-PPFs with a scanning electron microscope revealed that they are composed of nano-scale islands.

  11. Single-experiment simultaneous-measurement of elemental mass-attenuation coefficients of hydrogen, carbon and oxygen for 0.123-1.33 MeV gamma rays

    International Nuclear Information System (INIS)

    As it is inconvenient to use elements like hydrogen, carbon and oxygen in pure forms for measurement of their gamma mass-attenuation coefficients, the measurements are to be done indirectly, by using compounds of the elements or a mixture of them. We give here a simple method of measuring the total mass-attenuation coefficients μ/ρ of the elements in a compound simultaneously and in a single experiment through the measurements of the μ/ρ values of the concerned compounds and using the mixture rule. The method is applied for the measurement of μ/ρ of hydrogen, carbon and oxygen by using acetone, ethanol and 1-propanol. Our results (for Eγ=0.123-1.33 MeV) are seen to be in better agreement with the theoretical values of Hubbell and Seltzer (1995) [Hubbell J.H. and Seltzer S.M. (1995). Tables of X-ray mass attenuation coefficients and mass energy-absorption coefficients 1 keV to 20 MeV for elements Z=1 to 92 and 48 additional substances of dosimetric interest. NISTIR 5632] as compared to the results of El-Kateb and Abdul-Hamid (1991) [El-Kateb, A.H., Abdul-Hamid, A.S., 1991. Photon attenuation coefficient study of some materials containing hydrogen, carbon, and oxygen. Appl. Rad. Isot. 42, 303-307

  12. Protease activation in glycerol-based deep eutectic solvents

    Science.gov (United States)

    Zhao, Hua; Baker, Gary A.; Holmes, Shaletha

    2011-01-01

    Deep eutectic solvents (DESs) consisting of mixtures of a choline salt (chloride or acetate form) and glycerol are prepared as easily accessible, biodegradable, and inexpensive alternatives to conventional aprotic cation-anion paired ionic liquids. These DES systems display excellent fluidity coupled with thermal stability to nearly 200 °C. In this work, the transesterification activities of cross-linked proteases (subtilisin and α-chymotrypsin), immobilized on chitosan, were individually examined in these novel DESs. In the 1:2 molar ratio mixture of choline chloride/glycerol containing 3% (v/v) water, cross-linked subtilisin exhibited an excellent activity (2.9 μmo l min−1 g−1) in conjunction with a selectivity of 98% in the transesterification reaction of N-acetyl-L-phenylalanine ethyl ester with 1-propanol. These highly encouraging results advocate more extensive exploration of DESs in protease-mediated biotransformations of additional polar substrates and use of DESs in biocatalysis more generally. PMID:21909232

  13. Safety Evaluation of the Grape Marc Spirit by GC-FID Analysis

    Directory of Open Access Journals (Sweden)

    Teodora Coldea

    2013-11-01

    Full Text Available There were investigated grape marc spirits regarding their safety on consumers. Major volatile compounds which present risk to human health (such as methanol, furfural, and acetaldehyde and ethyl alcohol content were compared to European Union Regulation and other values found in previous studies.  The aim of our study was to evaluate the safety of grape marc spirits considering their content in major volatile compounds by comparison with the requirements of European Union Regulation. We investigated the ethyl alcohol content by electronic densimetry and 10 major volatile compounds (acetaldehyde, ethyl acetate, methanol, 1-propanol, 1-butanol, 2-butanol, isobutyl alcohol, isoamyl alcohol, amyl active alcohol and furfural by Gas Chromatography coupled with Flame Ionization Detector. We used reference chemicals to identify these compounds and 3-pentanol as internal standard to quantify the volatiles. Results were compared with the requirements of European Union Regulation. All major volatile compounds registered values in accordance to EU Regulation and the grape pomace spirits samples do not present any kind of risk for consumption.

  14. Use of Organic Solvents to Extract Organochlorine Pesticides (OCPs) from Aged Contaminated Soils

    Institute of Scientific and Technical Information of China (English)

    YE Mao; JIN Xin; JIANG Xin; YANG Xing-Lun; SUN Ming-Ming; BIAN Yong-Rong; WANG Fang; GU Cheng-Gang; WEI Hai-Jiang; SONG Yang; WANG Lei

    2013-01-01

    Problems associated with organochlorine pesticide (OCP)-contaminated sites in China have received wide attention.To solve such problems,innovative ex-situ methods of site remediation are urgently needed.We investigated the feasibility of the extraction method with different organic solvents,ethanol,1-propanol,and three fractions of petroleum ether,using a soil collected from Wujiang (WJ),China,a region with long-term contamination of dichlorodiphenyltrichloroethanes (DDTs).We evaluated different influential factors,including organic solvent concentration,washing time,mixing speed,solution-to-soil ratio,and washing temperature,on the removal of DDTs from the WJ soil.A set of relatively better parameters were selected for extraction with 100 mL L-1 petroleum ether (60-90 ℃):washing time of 180 min,mixing speed of 100 r min-1,solution-to-soil ratio of 10:1,and washing temperature of 50 ℃.These selected parameters were also applied on three other seriously OCP-polluted soils.Results demonstrated their broad-spectrum effectiveness and excellent OCP extraction performance on the contaminated soils with different characteristics.

  15. Microchip free flow planar reversed phase electrochromatography with monolithic stationary phase.

    Science.gov (United States)

    Wang, Pingli; Tao, Dingyin; Zhang, Lihua; Liang, Zhen; Zhang, Yukui

    2009-08-01

    In this study, microchip free flow planar RP electrochromatography (microFF-PRPEC) was developed by in situ polymerization of monolithic materials in microchamber, and successfully applied for the separation of dyes and proteins. Poly(butyle methyacrylate-co-ethylene dimethacrylate) was prepared by UV-initiated polymerization in a glass microchamber (42 mm long, 23 mm wide, and 28 microm deep). A mixture of 1-propanol, 1,4-butanediol, and water was chosen as porogens, and 1.2% (wt%) 2-acrylamide-2-methyl-propanesulfonic acid (AMPS) was added into the polymerization solution to generate EOF. With 30% v/v ACN-15 mM Tris-HCl as the mobile phase, rhodamine B and methyl green were separated from each other with 400 V transverse voltage applied, and resolution as high as 4.6 was obtained, much higher than that obtained by microFFE under optimal conditions. Furthermore, microFF-PRPEC was also successfully applied into the separation of lysozyme and ribonuclease B, and resolution as high as 9.4 was obtained. All these results demonstrate that microFF-RPPEC might have great potential in the microscale continuous preparation of samples with improved resolution compared to microFFE.

  16. Acid Lipase from Candida viswanathii: Production, Biochemical Properties, and Potential Application

    Directory of Open Access Journals (Sweden)

    Alex Fernando de Almeida

    2013-01-01

    Full Text Available Influences of environmental variables and emulsifiers on lipase production of a Candida viswanathii strain were investigated. The highest lipase activity (101.1 U was observed at 210 rpm, pH 6.0, and 27.5°C. Other fermentation parameters analyzed showed considerable rates of biomass yield ( g/h. Addition of soybean lecithin increased lipase production in 1.45-fold, presenting lipase yield ( of 10.061 U/g. Crude lipase presented optimal activity at acid pH of 3.5, suggesting a new lipolytic enzyme for this genus and yeast in general. In addition, crude lipase presented high stability in acid conditions and temperature between 40 and 45°C, after 24 h of incubation in these temperatures. Lipase remained active in the presence of organic solvents maintaining above 80% activity in DMSO, methanol, acetonitrile, ethanol, acetone, 1-propanol, isopropanol, and 2-propanol. Effectiveness for the hydrolysis of a wide range of natural triglycerides suggests that this new acid lipase has high potential application in the oleochemical and food industries for hydrolysis and/or modification of triacylglycerols to improve the nutritional properties.

  17. Acid lipase from Candida viswanathii: production, biochemical properties, and potential application.

    Science.gov (United States)

    de Almeida, Alex Fernando; Tauk-Tornisielo, Sâmia Maria; Carmona, Eleonora Cano

    2013-01-01

    Influences of environmental variables and emulsifiers on lipase production of a Candida viswanathii strain were investigated. The highest lipase activity (101.1 U) was observed at 210 rpm, pH 6.0, and 27.5°C. Other fermentation parameters analyzed showed considerable rates of biomass yield (Y L/S = 1.381 g/g), lipase yield (Y L/S = 6.892 U/g), and biomass productivity (P X = 0.282 g/h). Addition of soybean lecithin increased lipase production in 1.45-fold, presenting lipase yield (Y L/S ) of 10.061 U/g. Crude lipase presented optimal activity at acid pH of 3.5, suggesting a new lipolytic enzyme for this genus and yeast in general. In addition, crude lipase presented high stability in acid conditions and temperature between 40 and 45°C, after 24 h of incubation in these temperatures. Lipase remained active in the presence of organic solvents maintaining above 80% activity in DMSO, methanol, acetonitrile, ethanol, acetone, 1-propanol, isopropanol, and 2-propanol. Effectiveness for the hydrolysis of a wide range of natural triglycerides suggests that this new acid lipase has high potential application in the oleochemical and food industries for hydrolysis and/or modification of triacylglycerols to improve the nutritional properties.

  18. Rapid identification of vibrio-cholerae O1 by coaglutination test using mono-specifis antibody

    Directory of Open Access Journals (Sweden)

    Bazargan SA

    1996-07-01

    Full Text Available In our investigation, rabbit hyper-immune serum to V.cholerae ogawa was absorbed with V.cholerae inaba whole-cells and vice versa. Applying ammonium sulphate precipitation method, mono-specific g globulins were purified and concentrated from the absorbed whole serum. These antibodies were fixed on staphylococcus cowan 1 NCTC-8325 whole-cells, using different chemical fixatives. It was observed that maximum fixation of g globulin to protein-A was achieved by 1-propanol 50% at 3 hours, which revealed through single radial immuno-diffusion techniqe. The rectal swab samples were cultured in an enrichment bile-peptons broth. After 5 hours 37°C while agitations, one drop of each sample was mixed with one drop of vibrio-cholerae bivalent mono-specific coagglutination reagent (VBCR. The results were read after 2 to 3 minutes. Finally though statistical analysis sensitivity and specificity of coagglutination test were calculated to be 95.1% and 99.2% respectively, when compared to positive & negative controls and conventional culture methods. Using VBCR, coagglutination test can be therefore considered as a simple, reliable and rapid method to detect V.cholerae O1 in the stool of patients in endemic area and less equipped laboratories

  19. Catalytic Hydrogenation of Methanol-Containing Eflfuent from Epoxidation of Propylene

    Institute of Scientific and Technical Information of China (English)

    Cheng Ke

    2015-01-01

    This paper describes the hydrogenation of impurities in the methanol-containing eflfuent from the propylene epoxidation process with hydrogen peroxide. The effects of reaction temperature, pressure, weight hourly space velocity (WHSV) and H2/methanol ratio on the concentration of various impurities in methanol solvent were investigated. It was found out that the aldehyde, hydrogen peroxide and nitro compounds in the methanol solvent could be completely hydroge-nated over the Ni catalyst under proper reaction conditions. 90%of acetone and up to 50%of acetals (ketals) existing in the methanol solvent could be hydrogenated. No signiifcant change was observed for the rest of the impurities that were present in the methanol solvent (i. e., 1-methoxy-2-propanol, 2-methoxy-1-propanol and 1,2-propanediol). The H2O2 decomposition reaction was enhanced using Ni catalyst, through the formation of NioOH, but no oxygen was found in the off-gas of hy-drogenation reaction since NioH could react on NioOH formed via dissociative adsorption of hydrogen peroxide, or on NioO formed via adsorption of oxygen.

  20. Influence of Fermentation Temperature on the Quality of ‘Žilavka’ Wines

    Directory of Open Access Journals (Sweden)

    Tihomir Prusina

    2008-06-01

    Full Text Available ‘Žilavka’ is the autochthonous white grape variety of Herzegovina and there is a great interest of local winemakers to produce ‘Žilavka’ wines, which are characterized with a fine balance between the fermentation bouquet and grapebased aromas. The fermentation temperatures of some wineries in Herzegovina often can exceed 30°C what results with inferior overall wine quality. In this research changes in concentration of higher alcohols and sensory properties caused by fermentation at diff erent temperatures in ‘Žilavka’ wines were investigated. Compared to fermentation at the temperature above 26°C, fermentation at 15°C and 20°C caused signifi cant decrease in the concentration of total higher alcohols and individual isoamyl alcohol and isobutanol only in one year of the research. There were no differences in concentration of 1-propanol and ethyl acetate among all tested wines in both years. The best sensory evaluated were the wines fermented at 20°C, while the wines produced at the temperature above 25°C were of the most inferior quality.

  1. Methyl orbital signatures in 2-amino-l-propanol

    Institute of Scientific and Technical Information of China (English)

    Wang Ke-Dong; Duan Kun-Jie; Liu Yu-Fang

    2012-01-01

    Electron density distributions of 2-aminoethanol (2AE) and 2-amino-1-propanol (2AP) are calculated in both the coordinate and the momentum spaces using the B3LYP/TZVP method.Using the dual space analysis,molecular orbital signatures of the methyl substituent in 2AP are identified with respect to 2AE.Relaxations of the geometry and the valence orbital in 2AP are found to be due to the insertion of the methyl group.Five orbitals,not four orbitals,are identified as the methyl signatures.They are orbital 5a in the core shell,orbitals 9a and 10a in the inner valence shell,and orbitals 15a and 16a in the outer valence.In the inner valence shell,the attachment of methyl to 2AE causes a splitting of its orbital 8a into orbitals 9a and 10a of 2AP,whereas in the outer valence shell,the methyl group results in the insertion of an additional orbital pair of 15a and 16a.The frontier molecular orbitals 21a,20a,and 19a are found to have no significant role in the methylation of 2AE.

  2. Effect of acid catalysts and accelerated aging on the reaction of methanol with hydroxy-acetaldehyde in bio-oil

    Directory of Open Access Journals (Sweden)

    Bhattacharya, P.

    2010-05-01

    Full Text Available Bio-oil is a promising alternative source of energy produced from fast pyrolysis of biomass. Increasing the viscosity of bio-oil during storage is a major problem that can be controlled by the addition of methanol or other alcohols. This paper reports the results of our investigation of the reactions of short chain alcohols with aldehydes and acids in bio-oil. The reaction of methanol with hydroxyacetaldehyde (HA to form the acetal was catalyzed by the addition of 7 x 10-4 M strong acids such as sulfuric, hydrochloric, p-toluene sulfonic acid, and methanesulfonic acid. HA formed 2,2-dimethoxyethanol (DME, and at 60 oC the equilibrium was reached in less than one hour. Smaller amounts of DME were formed in the absence of strong acid. HA, acetaldehyde, and propanal formed their corresponding acetals when reacted with methanol, ethanol, 1-propanol or 1-butanol. Esters of acetic acid and hydroxyacetic acid were observed from reactions with these same four alcohols. Other acetals and esters were observed by GC/MS analysis of the reaction products. The results from accelerated aging experiments at 90 oC suggest that the presence of methanol slows polymerization by formation of acetals and esters from low molecular weight aldehydes and organic acids.

  3. Thermodynamic Properties of Transfer for Tetraphenylarsonium Tetraphylborate from Water to n—Alkanols

    Institute of Scientific and Technical Information of China (English)

    邹立壮; 路遥; 等

    2002-01-01

    Solubilities of tetraphenylarsonium tetraphenylborate(Ph4AsB-Ph4) in water,methanol,ethanol, 1-propanol,1-butanol,1-pentanol,1-hexanol and 1-octanol at T=293.2,298.2,303.2 and 308.2 K have been determined by spectrophotometry,The standard transfer Gibbs energy (△trG0w→s) and entropy (△trS0w→s) of Ph4AsBPh4 from water to the n-alkanols at temerature from 293.2 K to 308.2 K have been obtained.Fur-thermore,the contribution of microscopic interaction to the standard Gibbs energy of transfer for Ph4AsBPh4 was calculated and discussed,The results show that the effect of hydrophobic inderaction of Ph4AsBPh4 on its transfer process is the most im-portant factor .According to the thermodynamical principle,the transfer process of Ph4AsBPh4 from water to the n-alkanols is the entropy dominanted.

  4. Synthesis and pervaporation performance of high-reproducibility silicalite-1 membranes

    Institute of Scientific and Technical Information of China (English)

    CHEN HongLiang; LI YanShuo; Zhu GuangQi; LIU Jie; YANG WeiShen

    2008-01-01

    High-reproducibility silicalite-1 membranes were synthesized on silica tubes by in-situ hydrothermal synthesis, and the relative standard deviation (R.S.D.) of average separation factor for eight membranes was only 7.5%. By using an effective method called "solution-filling (SF)", the average flux of membranes prepared with SF method was improved by about 49% compared to membranes prepared without SF method, and the highest flux of membrane prepared with SF method towards ethanol/H2O mixture at 80℃ was 1.49 kg/(m2·h). Pervaporation experiments showed that the fluxes of silicalite-1 membranes at 60℃ were 2.63, 0.87, 0.24, and 0.20 kg/(m2·h) towards methanol/H2O, ethanol/H2O,2-propanol/H2O, and 1-propanol/H2O mixtures, respectively, and the corresponding separation factors were 22, 69, 81, and159, respectively.

  5. The Search for a Volatile Human Specific Marker in the Decomposition Process.

    Directory of Open Access Journals (Sweden)

    E Rosier

    Full Text Available In this study, a validated method using a thermal desorber combined with a gas chromatograph coupled to mass spectrometry was used to identify the volatile organic compounds released during decomposition of 6 human and 26 animal remains in a laboratory environment during a period of 6 months. 452 compounds were identified. Among them a human specific marker was sought using principle component analysis. We found a combination of 8 compounds (ethyl propionate, propyl propionate, propyl butyrate, ethyl pentanoate, pyridine, diethyl disulfide, methyl(methylthioethyl disulfide and 3-methylthio-1-propanol that led to the distinction of human and pig remains from other animal remains. Furthermore, it was possible to separate the pig remains from human remains based on 5 esters (3-methylbutyl pentanoate, 3-methylbutyl 3-methylbutyrate, 3-methylbutyl 2-methylbutyrate, butyl pentanoate and propyl hexanoate. Further research in the field with full bodies has to corroborate these results and search for one or more human specific markers. These markers would allow a more efficiently training of cadaver dogs or portable detection devices could be developed.

  6. A Sphingolipid Inhibitor Induces a Cytokinesis Arrest and Blocks Stage Differentiation in Giardia lamblia▿

    Science.gov (United States)

    Sonda, Sabrina; Štefanić, Saša; Hehl, Adrian B.

    2008-01-01

    Sphingolipid biosynthesis pathways have recently emerged as a promising target for therapeutic intervention against pathogens, including parasites. A key step in the synthesis of complex sphingolipids is the glucosylation of ceramide, mediated by glucosylceramide (GlcCer) synthase, whose activity can be inhibited by PPMP (1-phenyl-2-palmitoylamino-3-morpholino-1-propanol). In this study, we investigated whether PPMP inhibits the proliferation and differentiation of the pathogenic parasite Giardia lamblia, the major cause of parasite-induced diarrhea worldwide. PPMP was found to block in vitro parasite replication in a dose-dependent manner, with a 50% inhibitory concentration of 3.5 μM. The inhibition of parasite replication was irreversible at 10 μM PPMP, a concentration that did not affect mammalian cell metabolism. Importantly, PPMP inhibited the completion of cell division at a specific stage in late cytokinesis. Microscopic analysis of cells incubated with PPMP revealed the aberrant accumulation of cellular membranes belonging to the endoplasmic reticulum network in the caudal area of the parasites. Finally, PPMP induced a 90% reduction in G. lamblia differentiation into cysts, the parasite stage responsible for the transmission of the disease. These results show that PPMP is a powerful inhibitor of G. lamblia in vitro and that as-yet-uncharacterized sphingolipid biosynthetic pathways are potential targets for the development of anti-G. lamblia agents. PMID:18086854

  7. A sphingolipid inhibitor induces a cytokinesis arrest and blocks stage differentiation in Giardia lamblia.

    Science.gov (United States)

    Sonda, Sabrina; Stefanic, Sasa; Hehl, Adrian B

    2008-02-01

    Sphingolipid biosynthesis pathways have recently emerged as a promising target for therapeutic intervention against pathogens, including parasites. A key step in the synthesis of complex sphingolipids is the glucosylation of ceramide, mediated by glucosylceramide (GlcCer) synthase, whose activity can be inhibited by PPMP (1-phenyl-2-palmitoylamino-3-morpholino-1-propanol). In this study, we investigated whether PPMP inhibits the proliferation and differentiation of the pathogenic parasite Giardia lamblia, the major cause of parasite-induced diarrhea worldwide. PPMP was found to block in vitro parasite replication in a dose-dependent manner, with a 50% inhibitory concentration of 3.5 muM. The inhibition of parasite replication was irreversible at 10 muM PPMP, a concentration that did not affect mammalian cell metabolism. Importantly, PPMP inhibited the completion of cell division at a specific stage in late cytokinesis. Microscopic analysis of cells incubated with PPMP revealed the aberrant accumulation of cellular membranes belonging to the endoplasmic reticulum network in the caudal area of the parasites. Finally, PPMP induced a 90% reduction in G. lamblia differentiation into cysts, the parasite stage responsible for the transmission of the disease. These results show that PPMP is a powerful inhibitor of G. lamblia in vitro and that as-yet-uncharacterized sphingolipid biosynthetic pathways are potential targets for the development of anti-G. lamblia agents. PMID:18086854

  8. Experimental Measurement and Thermodynamic Modeling of the Solubility of Carbon Dioxide in Aqueous Alkanolamine Solutions in the High Gas Loading Region

    Science.gov (United States)

    Suleman, Humbul; Maulud, Abdulhalim Shah; Man, Zakaria

    2016-09-01

    The solubility of carbon dioxide in aqueous alkanolamine solutions was investigated in the high gas loading region based on experimental measurements and thermodynamic modeling. An experimental phase equilibrium study was performed to evaluate the absorption of carbon dioxide in aqueous solutions of five representative alkanolamines, including monoethanolamine, diethanolamine, N-methyldiethanolamine, 2-amino-2-methyl-1-propanol and piperazine. The carbon dioxide loadings of these solutions were determined for a wide range of pressures (62.5 kPa to 4150 kPa), temperatures (303.15 K to 343.15 K) and alkanolamine concentrations (2 M to 4 M). The results were found to be largely consistent with those previously reported in the literature. Furthermore, a hybrid Kent-Eisenberg model was developed for the correlation of the experimental data points. This new model incorporated an equation of state/excess Gibbs energy model for determining the solubility of carbon dioxide in the high-pressure-high gas loading region. This approach also used a single correction parameter, which was a function of the alkanolamine concentration. The results of this model were in excellent agreement with our experimental results. Most notably, this model was consistent with other reported values from the literature.

  9. Heterometallic Cu(II)-Dy(III) Clusters of Different Nuclearities with Slow Magnetic Relaxation.

    Science.gov (United States)

    Modak, Ritwik; Sikdar, Yeasin; Cosquer, Goulven; Chatterjee, Sudipta; Yamashita, Masahiro; Goswami, Sanchita

    2016-01-19

    The synthesis, structures, and magnetic properties of two heterometallic Cu(II)-Dy(III) clusters are reported. The first structural motif displays a pentanuclear Cu(II)4Dy(III) core, while the second one reveals a nonanuclear Cu(II)6Dy(III)3 core. We employed o-vanillin-based Schiff base ligands combining o-vanillin with 3-amino-1-propanol, H2vap, (2-[(3-hydroxy-propylimino)-methyl]-6-methoxy-phenol), and 2-aminoethanol, H2vae, (2-[(3-hydroxy-ethylimino)-methyl]-6-methoxy-phenol). The differing nuclearities of the two clusters stem from the choice of imino alcohol arm in the Schiff bases, H2vap and H2vae. This work is aimed at broadening the diversity of Cu(II)-Dy(III) clusters and to perceive the consequence of changing the length of the alcohol arm on the nuclearity of the cluster, providing valuable insight into promising future synthetic directions. The underlying topological entity of the pentanuclear Cu4Dy cluster is reported for the first time. The investigation of magnetic behaviors of 1 and 2 below 2 K reveals slow magnetic relaxation with a significant influence coming from the variation of the alcohol arm affecting the nature of magnetic interactions. PMID:26702645

  10. Use of micellar liquid chromatography to analyze oxolinic acid, flumequine, marbofloxacin and enrofloxacin in honey and validation according to the 2002/657/EC decision.

    Science.gov (United States)

    Tayeb-Cherif, K; Peris-Vicente, J; Carda-Broch, S; Esteve-Romero, J

    2016-07-01

    A micellar liquid chromatographic method was developed for the analysis of oxolinic acid, flumequine, marbofloxacin and enrofloxacin in honey. These quinolines are unethically used in beekeeping, and a zero-tolerance policy to antibiotic residues in honey has been stated by the European Union. The sample pretreatment was a 1:1 dilution with a 0.05M SDS at pH 3 solution, filtration and direct injection, thus avoiding extraction steps. The quinolones were eluted without interferences using mobile phase of 0.05M SDS/12.5% 1-propanol/0.5% triethylamine at pH 3, running at 1mL/min under isocratic room through a C18 column. The analytes were detected by fluorescence. The method was successfully validated according to the requirements of the European Union Decision 2002/657/EC in terms of: specificity, linearity (r(2)>0.995), limit of detection and decision limit (0.008-0.070mg/kg), lower limit of quantification (0.02-0.2mg/kg), detection capability (0.010-0.10mg/kg), recovery (82.1-110.0%), precision (effects, robustness (honey supplied by a local supermarket, and the studied antibiotics were not detected. Therefore, the method was rapid, simple, safe, eco friendly, reliable and useful for the routine analysis of honey samples. PMID:26920300

  11. Combustion of Methanol Droplets in Air-Diluent Environments with Reduced and Normal Gravity

    Directory of Open Access Journals (Sweden)

    Benjamin Shaw

    2012-01-01

    Full Text Available Reduced and normal gravity combustion experiments were performed with fiber-supported methanol droplets with initial diameters in the 1 mm size range. Experiments were performed with air-diluent mixtures at about 0.101 MPa and 298 K, where carbon dioxide, helium, or xenon was separately used as the diluent gas. Results indicate that ambient gas transport properties play an important role in determining flammability and combustion behaviors including burning rates and radiant heat output histories of the droplets. Droplets would burn with significantly higher mole fractions of xenon than helium or carbon dioxide. In reduced gravity, droplets would burn steadily with a xenon mole fraction of 0.50 but would not burn steadily if helium or carbon dioxide mole fractions were 0.50. Comparison with previous experimental data shows that ignitability and combustion characteristics of droplets are influenced by the fuel type and also the gravitational level. Burning rates were about 40% to 70% higher in normal gravity than in reduced gravity. Methanol droplets also had burning rates that were typically larger than 1-propanol burning rates by about 20% in reduced gravity. In normal gravity, however, burning rate differences between the two fuels were significantly smaller.

  12. Identification of the degradation pathways of alkanolamines with TiO{sub 2} photocatalysis

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Chung-Shin, E-mail: cslu6@ntcnc.edu.tw [Department of General Education, National Taichung Nursing College, Taichung 403, Taiwan (China); Chen, Chiing-Chang [Department of Science Application and Dissemination, National Taichung University, Taichung 403, Taiwan (China); Mai, Fu-Der [Department of Biochemistry, School of Medicine, Taipei Medical University, Taipei 110, Taiwan (China); Li, Hua-Kuang [Department of General Education, National Taichung Nursing College, Taichung 403, Taiwan (China)

    2009-06-15

    The present study deals with the photocatalytic degradation of the alkanolamine, 2-dimethylamino-2-methyl-1-propanol (DMAMP), in the presence of TiO{sub 2} particles and UV-A ({lambda} = 365 nm) radiation. The obtained results show complete oxidation of DMAMP after 20 h, and a little over 90% of DMAMP was mineralization after 64-h of treatment. The effects of the solution pH, catalyst loading, and anions on the photocatalytic degradation of DMAMP were investigated, as well as the reaction intermediates that were formed during treatment. To the best of our knowledge, this is the first time that reports the degradation pathways of DMAMP. A number of intermediates were identified by GC/MS techniques during the treatment of DMAMP, following three tentative degradation routes. The first one is based on the oxidation of the primary alcohol group leading to the formation of corresponding aldehyde and carboxylic acid. The second route is based on the rupture of the N-C bond to form 2-methylpropanal and acetone. The last degradation route is based on the cyclization of the {beta}-amino alcohol group to form the oxazolidine derivatives.

  13. Identification of the degradation pathways of alkanolamines with TiO2 photocatalysis

    International Nuclear Information System (INIS)

    The present study deals with the photocatalytic degradation of the alkanolamine, 2-dimethylamino-2-methyl-1-propanol (DMAMP), in the presence of TiO2 particles and UV-A (λ = 365 nm) radiation. The obtained results show complete oxidation of DMAMP after 20 h, and a little over 90% of DMAMP was mineralization after 64-h of treatment. The effects of the solution pH, catalyst loading, and anions on the photocatalytic degradation of DMAMP were investigated, as well as the reaction intermediates that were formed during treatment. To the best of our knowledge, this is the first time that reports the degradation pathways of DMAMP. A number of intermediates were identified by GC/MS techniques during the treatment of DMAMP, following three tentative degradation routes. The first one is based on the oxidation of the primary alcohol group leading to the formation of corresponding aldehyde and carboxylic acid. The second route is based on the rupture of the N-C bond to form 2-methylpropanal and acetone. The last degradation route is based on the cyclization of the β-amino alcohol group to form the oxazolidine derivatives.

  14. Oleic acid based heterolipid synthesis, characterization and application in self-microemulsifying drug delivery system.

    Science.gov (United States)

    Kalhapure, Rahul S; Akamanchi, Krishnacharya G

    2012-04-01

    There is increasing demand for lipids owing to their use in formulating lipid based drug delivery systems of poorly soluble drugs. The present work discusses the synthesis, characterization of oleic acid based heterolipid and its use as oil in the development of self-microemulsifying drug delivery system (SMEDDS) for parenteral delivery. Synthesis was carried out by Michael addition of tert-butyl acrylate to 3-amino-1-propanol to obtain di-tert-butyl aminopropanol derivative. Reaction of this di-tert-butyl aminopropanol derivative with oleoyl chloride using p-dimethylaminopyridine as a coupling agent gave the desired heterolipid. It was characterized by (1)H NMR, (13)C NMR and MS to confirm the structure. It did not exhibit any measurable cytotoxicity, even up to 80μg/ml concentration. Application in parenteral drug delivery was explored using furosemide (FUR), a BCS class IV drug, as a model. FUR showed three times greater solubility in the heterolipid as compared to oleic acid. SMEDDSs were developed using heterolipid as oily phase, Solutol HS 15(®) as surfactant and ethanol as a co-surfactant. Developed SMEDDS could form spontaneous microemulsion on addition to various aqueous phases with mean globule size <70nm without any phase separation or drug precipitation even after 24h, and exhibited negligible hemolytic potential. PMID:22266534

  15. Postmortem degradation of administered ethanol-d6 and production of endogenous ethanol: experimental studies using rats and rabbits.

    Science.gov (United States)

    Takayasu, T; Ohshima, T; Tanaka, N; Maeda, H; Kondo, T; Nishigami, J; Nagano, T

    1995-12-18

    Deuterium-labeled ethanol-d6 was employed to study the metabolism and postmortem change of ethanol in putrefied organ tissues. First, 4 ml/kg body weight of 25% (w/v) solution of ethanol-d6 was administered orally to each of 15 rats. The heart blood and organs were collected 15-90 min after the administration and the ethanol-d6 was analyzed by head space gas chromatography/mass spectrometry. The ethanol-d6 concentration in the organ tissues reached its maximum at 15 min after the administration and then gradually declined, showing the same pattern as human ethanol metabolism. Ethanol-d6 (3 ml of the same solution/kg body weight) was injected into the vein of a rabbit's ear (total of 12 rabbits). The rabbit was killed with carbon monoxide 30 min after the administration and the carcass was allowed to stand for 1-4 days at 30 degrees C in a moist chamber. The concentration of ethanol-d6 decreased moderately. Postmortem ethanol and 1-propanol concentrations, in contrast, showed marked increases 2.5 days and more after sacrifice in line with the degree of putrefaction of each organ tissue including skeletal muscle. This suggests the postmortem activation of micro-organism activity. These results indicate that ethanol concentrations in cadaver tissues must be carefully assessed with due consideration of postmortem degradation and production.

  16. Cloud point measurements of 1-butyl-2,3-dimethylimidazolium tetrafluoroborate with alcohols

    Energy Technology Data Exchange (ETDEWEB)

    Li Xiaoli [Department of Chemistry and Chemical Engineering, Division of Material Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192 (Japan); Tamura, Kazuhiro, E-mail: tamura@t.kanazawa-u.ac.j [Department of Chemistry and Chemical Engineering, Division of Material Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192 (Japan)

    2010-12-15

    Mutual solubility data of imidazolium-based ionic liquid, 1-butyl-2,3-dimethylimidazolium tetrafluoroborate ([bmmim][BF{sub 4}]) with the alcohols, 1-propanol, 2-propanol, 1-butanol, 1-pentanol, and 1-hexanol were obtained by a cloud point method. The upper critical solution temperatures of the ionic liquid and alcohol mixtures were determined from the mutual solubility data. The upper critical solution temperature of the binary mixtures gradually increased as the chain length of the alcohol increased. The mutual solubility data of binary systems ([bmmim][BF{sub 4}] + alcohols) have been correlated by the original UNIQUAC model as well as the extended and modified form of the UNIQUAC model. The temperature dependence of the mutual solubility data could be represented in terms of the temperature dependence of the binary energy parameters obtained from the correlation. Additionally the influence of water contamination on the ionic liquid mixture was shown experimentally by adding pure water into the binary mixture ([bmmim][BF{sub 4}] + 1-butanol).

  17. Highly conductive side chain block copolymer anion exchange membranes.

    Science.gov (United States)

    Wang, Lizhu; Hickner, Michael A

    2016-06-28

    Block copolymers based on poly(styrene) having pendent trimethyl styrenylbutyl ammonium (with four carbon ring-ionic group alkyl linkers) or benzyltrimethyl ammonium groups with a methylene bridge between the ring and ionic group were synthesized by reversible addition-fragmentation radical (RAFT) polymerization as anion exchange membranes (AEMs). The C4 side chain polymer showed a 17% increase in Cl(-) conductivity of 33.7 mS cm(-1) compared to the benzyltrimethyl ammonium sample (28.9 mS cm(-1)) under the same conditions (IEC = 3.20 meq. g(-1), hydration number, λ = ∼7.0, cast from DMF/1-propanol (v/v = 3 : 1), relative humidity = 95%). As confirmed by small angle X-ray scattering (SAXS), the side chain block copolymers with tethered ammonium cations showed well-defined lamellar morphologies and a significant reduction in interdomain spacing compared to benzyltrimethyl ammonium containing block copolymers. The chemical stabilities of the block copolymers were evaluated under severe, accelerated conditions, and degradation was observed by (1)H NMR. The block copolymer with C4 side chain trimethyl styrenylbutyl ammonium motifs displayed slightly improved stability compared to that of a benzyltrimethyl ammonium-based AEM at 80 °C in 1 M NaOD aqueous solution for 30 days. PMID:27216558

  18. Potencial de biocatálise enantiosseletiva de lipases microbianas Potential of enantioselective biocatalysis by microbial lipases

    Directory of Open Access Journals (Sweden)

    Patrícia de O. Carvalho

    2005-08-01

    Full Text Available Microbial lipases have a great potential for commercial applications due to their stability, selectivity and broad substrate specificity because many non-natural acids, alcohols or amines can be used as the substrate. Three microbial lipases isolated from Brazilian soil samples (Aspergillus niger; Geotrichum candidum; Penicillium solitum were compared in terms of their stability and as biocatalysts in the enantioselective esterification using racemic substrates in organic medium. The lipase from Aspergillus niger showed the highest activity (18.2 U/mL and was highly thermostable, retaining 90% and 60% activity at 50 ºC and 60 ºC after 1 hour, respectively. In organic medium, this lipase provided the best results in terms of enantiomeric excess of the (S-active acid (ee = 6.1% and conversion value (c = 20% in the esterification of (R,S-ibuprofen with 1-propanol in isooctane. The esterification reaction of the racemic mixture of (R,S-2-octanol with decanoic acid proceeded with high enantioselectivity when lipase from Aspergillus niger (E = 13.2 and commercial lipase from Candida antarctica (E = 20 were employed.

  19. Avaliação cromatográfica de compostos voláteis de cachaças produzidas com leveduras de diferentes procedências Chromatographic evaluation of volatile compounds in brazilian sugar cane spirits produced with yeasts from different locations

    Directory of Open Access Journals (Sweden)

    Paulo Henrique Alves da Silva

    2009-03-01

    Full Text Available Procurou-se neste trabalho produzir cachaças em escala de laboratório a partir de leveduras isoladas de alambiques de diferentes regiões de Minas Gerais, avaliando-se e comparando-se a composição química destas em relação a cachaças de marcas comerciais. Os alambiques selecionados para isolamento das leveduras produzem tradicionalmente cachaças com características artesanais, cujos procedimentos as diferenciam sensorial e quimicamente das cachaças industriais. Avaliou-se a cinética de algumas das fermentações com relação ao teor alcoólico e à acidez produzidos durante a fermentação e alguns mostos atingiram concentrações de etanol da ordem de 9 ºGL e acidez de 55 mg.100 mL-1. Os compostos avaliados por cromatografia gasosa foram acetaldeído, acetato de etila, metanol, 1-propanol, álcool isobutílico, álcool isoamílico, furfural e ácido acético. As concentrações mais elevadas foram de alcoóis superiores totais, preponderando o álcool isoamílico, e de ácido acético. A composição mostrou-se bastante variável (40,59 a 671,86 mg de ácido acético.100 mL-1 de álcool anidro e 20,68 a 178,6 mg de acetaldeído.100 mL-1 de álcool anidro, e foi contrastada com os limites legais estabelecidos pela legislação brasileira (Instrução Normativa nº 13, de 30/06/2005, do Ministério da Agricultura, Pecuária e Abastecimento.The aim of this study was to produce Brazilian sugar cane spirits (cachaça in a laboratory scale using yeasts isolated from distilleries of different regions in Minas Gerais state evaluating and comparing their chemical composition to those of commercial brands of cachaça. The selected distilleries are from the segment of cachaça artisanal production, which includes different sensorial and chemical procedures from the ones produced in an industrial scale. Some kinetic processes were evaluated analyzing the alcoholic content and acidity produced during fermentation. Some fermenting musts showed

  20. Preparation and characterization of poly-(methacrylatoethyl trimethylammonium chloride-co-vinylbenzyl chloride-co-ethylene dimethacrylate monolith

    Directory of Open Access Journals (Sweden)

    Eko Malis

    2015-05-01

    Full Text Available A polymer monolithic column, poly-(methacrylatoethyltrimethylammonium chloride-co-vinylbenzyl chloride-co-ethylene dimethacrylate or poly-(MATE-co-VBC-co-EDMA was successfully prepared in the current study by one-step thermally initiated in situ polymerization, confined in a steel tubing of 0.5 mm i.d. and 1/16” o.d. The monoliths were prepared from methacrylatoethyltrimethylammonium chloride (MATE and vinylbenzyl chloride (VBC as monomer and ethylene dimethacrylate (EDMA as crosslinker using a binary porogen system of 1-propanol and 1,4-butanediol. The inner wall of steel tubing was pretreated with 3-methacryloxypropyl-trimethoxysilane (MAPS. In order to obtain monolith with adequate column efficiency and low flow resistance, some parameters such as total monomer concentration (%T and crosslinker concentration (%C were optimized. The morphology of this monolith was assessed by scanning electron microscopy (SEM. The properties of the monolithic column, such as permeability, binding capacity, and pore size distribution were also characterized in detail. From the results of the characterization of all monolith variation, monolith with %T 30 %C 50 and %T 35 %C 50 give the best characteristic. These monoliths have high permeability, adequate molecular recognition sites (represented with binding capacity value of over 20 mg/mL, and have over 80% flow through pores in their pore structure contribute to low flow resistance. The resulted monolithic columns have promising potential for dual mode liquid chromatography. MATE may contribute for anion-exchange while VBC may responsible for reversed-phase liquid chromatography.

  1. Alcohol metabolism by oral streptococci and interaction with human papillomavirus leads to malignant transformation of oral keratinocytes.

    Science.gov (United States)

    Tao, Lin; Pavlova, Sylvia I; Gasparovich, Stephen R; Jin, Ling; Schwartz, Joel

    2015-01-01

    Poor oral hygiene, ethanol consumption, and human papillomavirus (HPV) are associated with oral and esophageal cancers. However, the mechanism is not fully known. This study examines alcohol metabolism in Streptococcus and its interaction with HPV-16 in the malignant transformation of oral keratinocytes. The acetaldehyde-producing strain Streptococcus gordonii V2016 was analyzed for adh genes and activities of alcohol and aldehyde dehydrogenases. Streptococcus attachment to immortalized HPV-16 infected human oral keratinocytes, HOK (HPV/HOK-16B), human oral buccal keratinocytes, and foreskin keratinocytes was studied. Acetaldehyde, malondialdehyde, DNA damage, and abnormal proliferation among keratinocytes were also quantified. We found that S. gordonii V2016 expressed three primary alcohol dehydrogenases, AdhA, AdhB, and AdhE, which all oxidize ethanol to acetaldehyde, but their preferred substrates were 1-propanol, 1-butanol, and ethanol, respectively. S. gordonii V2016 did not show a detectable aldehyde dehydrogenase. AdhE is the major alcohol dehydrogenase in S. gordonii. Acetaldehyde and malondialdehyde production from permissible Streptococcus species significantly increased the bacterial attachment to keratinocytes, which was associated with an enhanced expression of furin to facilitate HPV infection and several malignant phenotypes including acetaldehyde adduct formation, abnormal proliferation, and enhanced migration through integrin-coated basement membrane by HPV-infected oral keratinocytes. Therefore, expression of multiple alcohol dehydrogenases with no functional aldehyde dehydrogenase contributes to excessive production of acetaldehyde from ethanol by oral streptococci. Oral Streptococcus species and HPV may cooperate to transform oral keratinocytes after ethanol exposure. These results suggest a significant clinical interaction, but further validation is warranted.

  2. Prediction of aged red wine aroma properties from aroma chemical composition. Partial least squares regression models.

    Science.gov (United States)

    Aznar, Margarita; López, Ricardo; Cacho, Juan; Ferreira, Vicente

    2003-04-23

    Partial least squares regression (PLSR) models able to predict some of the wine aroma nuances from its chemical composition have been developed. The aromatic sensory characteristics of 57 Spanish aged red wines were determined by 51 experts from the wine industry. The individual descriptions given by the experts were recorded, and the frequency with which a sensory term was used to define a given wine was taken as a measurement of its intensity. The aromatic chemical composition of the wines was determined by already published gas chromatography (GC)-flame ionization detector and GC-mass spectrometry methods. In the whole, 69 odorants were analyzed. Both matrixes, the sensory and chemical data, were simplified by grouping and rearranging correlated sensory terms or chemical compounds and by the exclusion of secondary aroma terms or of weak aroma chemicals. Finally, models were developed for 18 sensory terms and 27 chemicals or groups of chemicals. Satisfactory models, explaining more than 45% of the original variance, could be found for nine of the most important sensory terms (wood-vanillin-cinnamon, animal-leather-phenolic, toasted-coffee, old wood-reduction, vegetal-pepper, raisin-flowery, sweet-candy-cacao, fruity, and berry fruit). For this set of terms, the correlation coefficients between the measured and predicted Y (determined by cross-validation) ranged from 0.62 to 0.81. Models confirmed the existence of complex multivariate relationships between chemicals and odors. In general, pleasant descriptors were positively correlated to chemicals with pleasant aroma, such as vanillin, beta damascenone, or (E)-beta-methyl-gamma-octalactone, and negatively correlated to compounds showing less favorable odor properties, such as 4-ethyl and vinyl phenols, 3-(methylthio)-1-propanol, or phenylacetaldehyde.

  3. Inactivation of Staphylococcus aureus in Oat and Soya Drinks by Enterocin AS-48 in Combination with Other Antimicrobials.

    Science.gov (United States)

    Burgos, María José Grande; Aguayo, M Carmen López; Pulido, Rubén Pérez; Gálvez, Antonio; López, Rosario Lucas

    2015-09-01

    The presence of toxicogenic Staphylococcus aureus in foods and the dissemination of methicillin-resistant S. aureus (MRSA) in the food chain are matters of concern. In the present study, the circular bacteriocin enterocin AS-48, applied singly or in combination with phenolic compounds (carvacrol, eugenol, geraniol, and citral) or with 2-nitro-1-propanol (2NPOH), was investigated in the control of a cocktail made from 1 methicillin-sensitive and 1 MRSA strains inoculated on commercial oat and soya drinks. Enterocin AS-48 exhibited low bactericidal activity against staphylococci in the drinks investigated when applied singly. The combinations of sub-inhibitory concentrations of enterocin AS-48 (25 μg/mL) and phenolic compounds or 2NPOH caused complete inactivation of staphylococci in the drinks within 24 h of incubation at 22 °C. When tested in oat and soya drinks stored for 7 d at 10 °C, enterocin AS-48 (25 μg/mL) in combination with 2NPOH (5.5 mM) reduced viable counts rapidly in the case of oat drink (4.2 log cycles after 12 h) or slowly in soya drink (3.8 log cycles after 3 d). The same combined treatment applied on drinks stored at 22 °C achieved a fast inactivation of staphylococci within 12 to 24 h in both drinks, and no viable staphylococci were detected for up to 7 d of storage. Results from the study highlight the potential of enterocin AS-48 in combination with 2NPOH for inactivation of staphylococci.

  4. Time-activity relationships to VOC personal exposure factors

    Science.gov (United States)

    Edwards, Rufus D.; Schweizer, Christian; Llacqua, Vito; Lai, Hak Kan; Jantunen, Matti; Bayer-Oglesby, Lucy; Künzli, Nino

    Social and demographic factors have been found to play a significant role in differences between time-activity patterns of population subgroups. Since time-activity patterns largely influence personal exposure to compounds as individuals move across microenvironments, exposure subgroups within the population may be defined by factors that influence daily activity patterns. Socio-demographic and environmental factors that define time-activity subgroups also define quantifiable differences in VOC personal exposures to different sources and individual compounds in the Expolis study. Significant differences in exposures to traffic-related compounds ethylbenzene, m- and p-xylene and o-xylene were observed in relation to gender, number of children and living alone. Categorization of exposures further indicated time exposed to traffic at work and time in a car as important determinants. Increased exposures to decane, nonane and undecane were observed for males, housewives and self-employed. Categorization of exposures indicated exposure subgroups related to workshop use and living downtown. Higher exposures to 3-carene and α-pinene commonly found in household cleaning products and fragrances were associated with more children, while exposures to traffic compounds ethylbenzene, m- and p-xylene and o-xylene were reduced with more children. Considerable unexplained variation remained in categorization of exposures associated with home product use and fragrances, due to individual behavior and product choice. More targeted data collection methods in VOC exposure studies for these sources should be used. Living alone was associated with decreased exposures to 2-methyl-1-propanol and 1-butanol, and traffic-related compounds. Identification of these subgroups may help to reduce the large amount of unexplained variation in VOC exposure studies. Further they may help in assessing impacts of urban planning that result in changes in behavior of individuals, resulting in shifts in

  5. Phytochemical analysis and antagonistic activity of Ixora macrothyrsa on multidrug resistant bacteria

    Institute of Scientific and Technical Information of China (English)

    Femina Wahab; Kalidass Subramaniam; Sembian Suriyamoorthy; Sweetin Preethi Subburaj

    2012-01-01

    Objective: The present investigation was an attempt to identify the potent drug principles ofIxora macrothyrsa flower against Methicillin Resistant Staphylococcus aureus and Acinetobacter baumannii. Methods: Hot extraction soxhlet method was performed for the extraction of Ixora macrothyrsa flower powder with different solvents. Antagonistic activity checked for all extracts with MTCC standard pathogenic strains and multiple drug resistant strains. Followed this minimal inhibitory concentration, phenol estimation, High performance thin layer chromatography analysis and Gas chromatography- mass spectrometry analysis were performed for Ixora macrothyrsa ethanolic extract. Results: The results from the present study indicate that the flowers of the plant has rich source of phytochemicals in ethanol extracts compare to acetone and methanol extracts. The quantitative estimation of ethanolic extracts of Ixora macrothyrsa showed phenol content 83.67±.04 μg/g of ascorbic acid equivalent. The ethanol extract exhibited good antibacterial activity against all tested pathogens. In this study we point out that ethanol and methanol extracts showed supreme activity against Methicillin Resistant Staphylococcus aureus (MRSA) and Acinetobacter baumannii. The MIC of Ixora macrothyrsa ethanolic extract was identified as 22μg/ml for MRSA and 200μg/ml for Acinetobacter baumannii. The HPTLC analysis of the ethanol plant extract inferred that it contain both polyphenol and terpenoids. In GC-MS analysis the major constituent was identified as Ethene (2-chloroethoxy)-, 1-propanol 2-chloro, urethane with 16.39 area %. Conclusions: Hence it is inferred from our study that the plant flower would be a promising source of phytomedicine against multidrug resistant strains MRSA and Acinetobacter baumannii.

  6. Synthesis of Biodiesel from the Oily Content of Marine Green Alga Ulva fasciata

    International Nuclear Information System (INIS)

    The present study is focused on the chemical transformation of oils derived from the marine green alga Ulva fasciata Delile to biodiesel. The transesterification of algal oil was performed with a variety of alcohols using Na metal and NaOH as catalysts. Transesterification of algal oil by mechanical stirring yielded significant biodiesel within an hour at 60 degree C with NaOH and at room temperature with Na metal. In addition, microwave irradiated transesterification produced significant amount of biodiesel with NaOH and Na metal within 1-5 minutes. However, reaction of sodium metal in microwave oven was highly exothermic and uncontrollable that could also damage the radiation source. The reactivity order of alcohols was found to be methanol > ethanol > benzyl alcohol > 1-propanol > 1-butanol > 1-pentanol > 1-hexanol > 2-propanol. Isopropyl alcohol was found to be least reactive due to steric hindrance. Benzyl alcohol was found to be more reactive than 1-propyl alcohol due to the electron withdrawing effect of benzene ring. The highest % conversion of FAME and FAEE were found to be 97% and 98% respectively using Na metal through mechanical stirring. Biodiesel production was confirmed by thin layer chromatography (TLC). Furthermore, the fuel properties including density, kinematics viscosity, high heating value, acid value, free fatty acid (%), cloud point and pour point of U. fasciata oil and all the esters were determined and compared with the standard limits of biodiesel. Fatty acid methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 1-pentyl and 1-hexyl esters showed the fuel properties within the biodiesel standard limits therefore all of them were considered as the substitute of biodiesel. On the other hand, the fuel properties of benzyl ester were found to be above the limits of biodiesel specifications and thus it could not be considered as biodiesel. This research article will be helpful to overcome the current challenges of energy crisis, global warming and

  7. Development and validation of an analytical method for the separation and determination of major bioactive curcuminoids in Curcuma longa rhizomes and herbal products using non-aqueous capillary electrophoresis.

    Science.gov (United States)

    Anubala, S; Sekar, R; Nagaiah, K

    2014-06-01

    A simple, fast and efficient non-aqueous capillary electrophoresis method (NACE) was developed for the simultaneous determination of three major bioactive curcuminoids (CMNs) in Curcuma longa rhizomes and its herbal products. Good separation, resolution and reproducibility were achieved with the background electrolyte (BGE) consisting a mixture of 15.0 mM sodium tetraborate and 7.4 mM sodium hydroxide (NaOH) in 2:10:15 (v/v/v) of water, 1-propanol, and methanol. The influences of background electrolyte, sodium hydroxide, water, sodium dodecyl sulfate and hydroxylpropyl-β-cyclodextrin on separations were investigated. The separation was carried out in a fused-silica capillary tube with reverse polarity. Hydrodynamic injection of 25mbar for 12s was used for injecting samples and a voltage of 28 kV was applied for separation. The ultrasonication method was used for the extraction of CMNs from the turmeric herbal products and the extract was filtered and directly injected without any further treatments. The limits of detection and quantification were less than 5.0 and 14.6 µg/ml respectively for all CMNs. The percentage recoveries for CMNs were >97.2% (%RSD, <2.62). The results obtained by the method were compared with existing spectrophotometric and HPLC methods. The related compounds in the extract did not interfere in the determination of CMNs. The proposed NACE method is better than existing chromatographic and electrophoretic methods in terms of simple electrophoretic medium, fast analysis and good resolution.

  8. [Influences of uncommon isoenzymes on determination of alkaline phosphatase activity by dry-chemistry analyzers].

    Science.gov (United States)

    Tozawa, T; Hashimoto, M

    2001-04-01

    Dry-chemistry(DC) analysis may be influenced by some matrix effects for measuring uncommon isoenzyme forms. Placental and intestinal alkaline phosphatase(AP) are overestimated by the VITROS DC, compared with results obtained with the wet-chemistry(WC) method of Bretaudiere, et al. using 2-amino-2-methyl-1-propanol (AMP) buffer, however, no such discrepancy between AP results in any DC method and that with a routine WC method recommended by Japanese Society of Clinical Chemistry in that 2-ethylaminoethanol(EAE) buffer is used, has been demonstrated. The type of buffer used affects differently the rates of AP isoenzymes activities. We therefore examined whether the presence of uncommon AP isoenzyme forms in serum caused aberrant DC results for AP in comparison with a routine WC method using EAE buffer. Here, serum samples with only liver AP and bone AP(n : 32); high-molecular-mass AP(n : 11); placental AP(n : 12); intestinal AP(n : 13) and immunoglobulin (Ig) bound AP(n : 12) were analyzed for total AP activity on three different DC analyzers: VITROS 700XR, FUJIDRYCHEM 5000, SPOTCHEM 4410 and a WC analyzer: HITACHI 7350. Values obtained in all of the DCs for sera containing only liver/bone AP agreed with those with the WC method. For sera containing placental AP, the VITROS values were higher than those with the WC method, while the FUJIDRYCHEM values and the SPOTCHEM values were lower. The VITROS values and the FUJIDRYCHEM values for sera containing intestinal AP were lower than those with the WC method, while the SPOTCHEM values were higher. All of the DCs did not affect high-molecular-mass AP and Ig bound liver/bone AP types of macro AP, but underestimated Ig bound intestinal type. Ig bound intestinal AP may be sieved by DC multilayer elements. PMID:11391954

  9. Development and validation of LC methods for the separation of misoprostol related substances and diastereoisomers.

    Science.gov (United States)

    Kahsay, Getu; Song, Huiying; Eerdekens, Fran; Tie, Yaxin; Hendriks, Danny; Van Schepdael, Ann; Cabooter, Deirdre; Adams, Erwin

    2015-01-01

    Misoprostol is a synthetic prostaglandin E1 analogue which is mainly used for prevention and treatment of gastric ulcers, but also for abortion due to its labour inducing effect. Misoprostol exists as a mixture of diastereoisomers (1:1) and has several related impurities owing to its instability at higher temperatures and moisture. A simple and robust reversed phase liquid chromatographic (RPLC) method is described for the separation of the related substances and a normal phase (NP) LC method for the separation of misoprostol diastereoisomers. The RPLC method was performed using an Ascentis Express C18 (150 mm × 4.6 mm, 5 μm) column kept at 35 °C. The mobile phase was a gradient mixture of mobile phase A (ACN-H2O-MeOH, 28:69:3 v/v/v) and mobile phase B (ACN-H2O-MeOH, 47:50:3 v/v/v) eluted at a flow rate of 1.5 mL/min. UV detection was performed at 200 nm. The NPLC method was undertaken by using an XBridge bare silica (150 mm × 2.1 mm, 3.5 μm) column at 35 °C. The mobile phase contained 1-propanol-heptane-TFA (4:96:0.1%, v/v/v), pumped at a flow rate of 0.5 mL/min. UV detection was performed at 205 nm. This LC method can properly separate the two diastereoisomers (Rs > 2) within an analysis time of less than 20 min. Both methods were validated according to the ICH guidelines. Furthermore, these new LC methods have been successfully applied for purity control and diastereoisomers ratio determination of misoprostol bulk drug, tablets and dispersion.

  10. Preparation of a polymeric ionic liquid-based adsorbent for stir cake sorptive extraction of preservatives in orange juices and tea drinks.

    Science.gov (United States)

    Chen, Lei; Huang, Xiaojia

    2016-04-15

    In this study, a new polymeric ionic liquid-based adsorbent was prepared and used as the extraction medium of stir cake sorptive extraction (SCSE) of three organic acid preservatives, namely, p-hydroxybenzoic acid, sorbic acid and cinnamic acid. The adsorbent was synthesized by the copolymerization of 1-ally-3-vinylimidazolium chloride (AV) and divinylbenzene (DVB) in the presence of a porogen solvent containing 1-propanol and 1,4-butanediol. The effect of the content of monomer and the porogen solvent in the polymerization mixture on the extraction performance was investigated thoroughly. The adsorbent was characterized by infrared spectroscopy, elemental analysis, scanning electron microscopy and mercury intrusion porosimetry. To obtain the optimal extraction conditions of SCSE/AVDVB for target analytes, key parameters including desorption solvent, adsorption and desorption time, ionic strength and pH value in sample matrix were studied in detail. The results showed that under the optimized conditions, the SCSE/AVDVB could extract the preservatives effectively through multiply interactions. At the same time, a simple and sensitive method by combining SCSE/AVDVB and high-performance liquid chromatography with diode array detection was developed for the simultaneous analysis of the target preservatives in orange juices and tea drinks. Low limits of detection (S/N = 3) and quantification limits (S/N = 10) of the proposed method for the target analytes were achieved within the range of 0.012-0.23 μg/L and 0.039-0.42 μg/L, respectively. The precision of the proposed method was evaluated in terms of intra- and inter-assay variability calculated as relative standard deviation (RSD), and it was found that the values were all below 10%. Finally, the proposed method was used to detect preservatives in different orange juice and tea drink samples successfully. The recoveries were in the range of 71.9-116%, and the RSDs were below 10% in the all cases.

  11. Ruminal fermentation of Anti-methanogenic Nitrate- and Nitro-Containing Forages In Vitro

    Directory of Open Access Journals (Sweden)

    Robin C. Anderson

    2016-08-01

    Full Text Available Nitrate, 3-nitro-1-propionic acid (NPA and 3-nitro-1-propanol (NPOH can accumulate in forages and be poisonous to animals if consumed in high enough amounts. These chemicals are also recognized as potent anti-methanogenic compounds, but plants naturally containing these chemicals have been studied little in this regard. Presently, we found that nitrate-, NPA- or NPOH-containing forages effectively decreased methane production, by 35 to 87%, during in vitro fermentation by mixed cultures of ruminal microbes compared to fermentation by cultures incubated similarly with alfalfa. Methane production was further decreased during incubation of mixed cultures also inoculated with Denitrobacterium detoxificans, a ruminal bacterium known to metabolize nitrate, NPA and NPOH. Inhibition of methanogens within the mixed cultures was greatest with the NPA- and NPOH-containing forages. Hydrogen accumulated in all the mixed cultures incubated with forages containing nitrate, NPA or NPOH but was dramatically higher, exceeding 40 µmol hydrogen/mL, in mixed cultures incubated with NPA-containing forage but not inoculated with D. detoxificans. This possibly reflects the inhibition of hydrogenase-catalyzed uptake of hydrogen produced via conversion of 50 µmol added formate per mL to hydrogen. Accumulations of volatile fatty acids revealed compensatory changes in fermentation in mixed cultures incubated with the nitrate-, NPA- and NPOH-containing forages as evidenced by lower accumulations of acetate, and in some cases higher accumulations of butyrate and lower accumulations of ammonia, iso-buytrate and iso-valerate compared to cultures incubated with alfalfa. Results reveal that nitrate, NPA and NPOH that accumulate naturally in forages can be made available within ruminal incubations to inhibit methanogenesis. Further research is warranted to determine if diets can be formulated with nitrate-, NPA- and NPOH-containing forages to achieve efficacious mitigation in

  12. Ruminal Fermentation of Anti-Methanogenic Nitrate- and Nitro-Containing Forages In Vitro

    Science.gov (United States)

    Anderson, Robin C.; Ripley, Laura H.; Bowman, Jan G. P.; Callaway, Todd R.; Genovese, Kenneth J.; Beier, Ross C.; Harvey, Roger B.; Nisbet, David J.

    2016-01-01

    Nitrate, 3-nitro-1-propionic acid (NPA) and 3-nitro-1-propanol (NPOH) can accumulate in forages and be poisonous to animals if consumed in high enough amounts. These chemicals are also recognized as potent anti-methanogenic compounds, but plants naturally containing these chemicals have been studied little in this regard. Presently, we found that nitrate-, NPA-, or NPOH-containing forages effectively decreased methane production, by 35–87%, during in vitro fermentation by mixed cultures of ruminal microbes compared to fermentation by cultures incubated similarly with alfalfa. Methane production was further decreased during the incubation of mixed cultures also inoculated with Denitrobacterium detoxificans, a ruminal bacterium known to metabolize nitrate, NPA, and NPOH. Inhibition of methanogens within the mixed cultures was greatest with the NPA- and NPOH-containing forages. Hydrogen accumulated in all the mixed cultures incubated with forages containing nitrate, NPA or NPOH and was dramatically higher, exceeding 40 μmol hydrogen/mL, in mixed cultures incubated with NPA-containing forage but not inoculated with D. detoxificans. This possibly reflects the inhibition of hydrogenase-catalyzed uptake of hydrogen produced via conversion of 50 μmol added formate per milliliter to hydrogen. Accumulations of volatile fatty acids revealed compensatory changes in fermentation in mixed cultures incubated with the nitrate-, NPA-, and NPOH-containing forages as evidenced by lower accumulations of acetate, and in some cases, higher accumulations of butyrate and lower accumulations of ammonia, iso-buytrate, and iso-valerate compared to cultures incubated with alfalfa. Results reveal that nitrate, NPA, and NPOH that accumulate naturally in forages can be made available within ruminal incubations to inhibit methanogenesis. Further research is warranted to determine if diets can be formulated with nitrate-, NPA-, and NPOH-containing forages to achieve efficacious mitigation

  13. Application of the extended real associated solution (ERAS) theory to excess molar enthalpies of benzaldehyde + 1-alkanols (C{sub 1} to C{sub 5}) at T = 298.15 K

    Energy Technology Data Exchange (ETDEWEB)

    Iloukhani, H., E-mail: iloukhani@basu.ac.ir [Department of Physical Chemistry, Faculty of Chemistry, University of Bu-Ali Sina, Hamedan 65174 (Iran, Islamic Republic of); Fattahi, M. [Department of Physical Chemistry, Faculty of Chemistry, University of Bu-Ali Sina, Hamedan 65174 (Iran, Islamic Republic of)

    2011-11-15

    Highlights: > Enthalpy of binary mixtures of {l_brace}benzaldehyde + 1-alkanols{r_brace} (C{sub 1} to C{sub 5}) determined. > Excess molar enthalpy, partial molar enthalpy, and intermolecular interaction functions were calculated. > Excess molar enthalpy was correlated as a function of mole fraction by using the Redlich-Kister equation. > The experimental results have been used to test the applicability of the ERAS-model, Wilson and NRTL equations. - Abstract: This paper reports excess molar enthalpies, H{sub m}{sup E}, for the binary mixtures of {l_brace}1-alkanols (2), namely, {l_brace}methanol, ethanol, 1-propanol, 1-butanol, and 1-pentanol{r_brace} with benzaldehyde (1){r_brace} at T = 298.15 K at ambient pressure over a whole range of mole fraction. The sign of H{sub m}{sup E} for all systems are positive and the magnitude of H{sub m}{sup E} values with increasing of chain length, increase. The Redlich-Kister polynomial equation was used to correlate H{sub m}{sup E}. The excess partial molar enthalpies of benzaldehyde, H{sub m,1}{sup E}, excess partial molar enthalpies of 1-alkanols (C{sub 1} to C{sub 5}), H{sub m,2}{sup E}, and excess partial molar enthalpies at infinite dilution, H{sub m,i}{sup E,0}, are calculated according to experimental excess molar enthalpies and Redlich-Kister polynomial equation. The extracted date were used to evaluated the so-called intermolecular interaction functions {partial_derivative}H{sub m,i}{sup E}/{partial_derivative}x{sub i} and {partial_derivative}H{sub m,i}{sup E}/{partial_derivative}x{sub j} in terms of enthalpy. The ERAS, Wilson and NRTL models have been applied for describing the H{sub m}{sup E}.

  14. New Cerium-Based Metal-Organic Scintillators for Radiation Detection

    Energy Technology Data Exchange (ETDEWEB)

    Boatner, Lynn A [ORNL; Neal, John S [ORNL; Ramey, Joanne Oxendine [ORNL; Chakoumakos, Bryan C [ORNL; Custelcean, Radu [ORNL; Van Loef, Edgar [Radiation Monitoring Devices, Watertown, MA; Markosyan, G [Radiation Monitoring Devices, Watertown, MA

    2013-01-01

    We have previously shown that a new class of scintillating materials can be developed based on the synthesis and crystal growth of rare-earth metal-organic compounds. The first scintillator of this type consisted of single crystals of CeCl3(CH3OH)4 that were grown from a methanol solution. These crystals were shown to be applicable to both gamma-ray and fast neutron detection. Subsequently, metal-organic scintillators consisting of the compound LaBr3(CH3OH)4 activated with varying levels of Ce3+ and of CeBr3(CH3OH)4 were grown in single crystal form. We have now extended the development of this new class of scintillators to more complex organic components by reacting rare-earth halides such as CeCl3 or CeBr3 with different isomers of propanol and butanol including 1-propanol, isobutanol, n-butanol, and tert-butanol. The reaction of CeCl3 or CeBr3 with these organics results in the formation of new and relatively complex molecular crystals whose structures were determined using single-crystal X-ray diffraction. These new metal-organic scintillating materials were grown in single crystal form from solution, and their scintillation characteristics have been investigated using X-ray-excited luminescence plus energy spectra obtained with gamma-ray and alpha-particle sources. If the reactions between the inorganic and organic components are not carried out under very dry and highly controlled conditions, molecular structures can be formed that incorporate waters of hydration. The present observation of scintillation in these hydrated rare-earth metal-organic compounds is apparently an original finding, since we are not aware of any previous reports of scintillation being observed in a material that incorporates waters of hydration

  15. Effects of new Torulaspora delbrueckii killer yeasts on the must fermentation kinetics and aroma compounds of white table wine

    Directory of Open Access Journals (Sweden)

    Rocío eVelázquez

    2015-11-01

    Full Text Available Torulaspora delbrueckii is becoming widely recommended for improving some specific characteristics of wines. However, its impact on wine quality is still far from satisfactory at the winery level, mostly because it is easily replaced by S. cerevisiae-like yeasts during must fermentation. New T. delbrueckii killer strains were here isolated and selected for winemaking. They killed S. cerevisiae yeasts and were able to dominate and complete the fermentation of sterile grape must. Sequential yeast inoculation of non-sterile white must with T. delbrueckii followed by S. cerevisiae did not ensure T. delbrueckii dominance or wine quality improvement. Only a single initial must inoculation at high cell concentrations allowed the T. delbrueckii killer strains to dominate and complete the must fermentation to reach above 11% ethanol, but not the non-killer strains. None of the wines underwent malolactic fermentation as long as the must had low turbidity and pH. Although no statistically significant differences were found in the wine quality score, the S. cerevisiae-dominated wines were preferred over the T. delbrueckii-dominated ones because the former had high-intensity fresh fruit aromas while the latter had lower intensity, but nevertheless nice and unusual dried fruit/pastry aromas. Except for ethyl propanoate and 3-ethoxy-1-propanol, which were more abundant in the T. delbrueckii–dominated wines, most of the compounds with fresh fruit odour descriptors, including those with the greatest odour activity values (isoamyl acetate, ethyl hexanoate, and ethyl octanoate, were more abundant in the S. cerevisiae–dominated wines. The low relative concentrations of these fruity compounds made it possible to detect in the T. delbrueckii–dominated wines the low-relative-concentration compounds with dried fruit and pastry odours. An example was γ-ethoxy-butyrolactone which was significantly more abundant in these wines than in those dominated by S

  16. Effects of new Torulaspora delbrueckii killer yeasts on the must fermentation kinetics and aroma compounds of white table wine.

    Science.gov (United States)

    Velázquez, Rocío; Zamora, Emiliano; Álvarez, María L; Hernández, Luis M; Ramírez, Manuel

    2015-01-01

    Torulaspora delbrueckii is becoming widely recommended for improving some specific characteristics of wines. However, its impact on wine quality is still far from satisfactory at the winery level, mostly because it is easily replaced by Saccharomyces cerevisiae-like yeasts during must fermentation. New T. delbrueckii killer strains were here isolated and selected for winemaking. They killed S. cerevisiae yeasts and were able to dominate and complete the fermentation of sterile grape must. Sequential yeast inoculation of non-sterile white must with T. delbrueckii followed by S. cerevisiae did not ensure T. delbrueckii dominance or wine quality improvement. Only a single initial must inoculation at high cell concentrations allowed the T. delbrueckii killer strains to dominate and complete the must fermentation to reach above 11% ethanol, but not the non-killer strains. None of the wines underwent malolactic fermentation as long as the must had low turbidity and pH. Although no statistically significant differences were found in the wine quality score, the S. cerevisiae-dominated wines were preferred over the T. delbrueckii-dominated ones because the former had high-intensity fresh fruit aromas while the latter had lower intensity, but nevertheless nice and unusual dried fruit/pastry aromas. Except for ethyl propanoate and 3-ethoxy-1-propanol, which were more abundant in the T. delbrueckii-dominated wines, most of the compounds with fresh fruit odor descriptors, including those with the greatest odor activity values (isoamyl acetate, ethyl hexanoate, and ethyl octanoate), were more abundant in the S. cerevisiae-dominated wines. The low relative concentrations of these fruity compounds made it possible to detect in the T. delbrueckii-dominated wines the low-relative-concentration compounds with dried fruit and pastry odors. An example was γ-ethoxy-butyrolactone which was significantly more abundant in these wines than in those dominated by S. cerevisiae. PMID:26579114

  17. Random mutagenesis and selection of organic solvent-stable haloperoxidase from Streptomyces aureofaciens.

    Science.gov (United States)

    Yamada, Ryosuke; Higo, Tatsutoshi; Yoshikawa, Chisa; China, Hideyasu; Yasuda, Masahiro; Ogino, Hiroyasu

    2015-01-01

    Haloperoxidases are useful oxygenases involved in halogenation of a range of water-insoluble organic compounds and can be used without additional high-cost cofactors. In particular, organic solvent-stable haloperoxidases are desirable for enzymatic halogenations in the presence of organic solvents. In this study, we adopted a directed evolution approach by error-prone polymerase chain reaction to improve the organic solvent-stability of the homodimeric BPO-A1 haloperoxidase from Streptomyces aureofaciens. Among 1,000 mutant BPO-A1 haloperoxidases, an organic solvent-stable mutant OST48 with P123L and P241A mutations and a high active mutant OST959 with H53Y and G162R mutations were selected. The residual activity of mutant OST48 after incubation in 40% (v/v) 1-propanol for 1 h was 1.8-fold higher than that of wild-type BPO-A1. In addition, the OST48 mutant showed higher stability in methanol, ethanol, dimethyl sulfoxide, and N,N-dimethylformamide than wild-type BPO-A1 haloperoxidase. Moreover, after incubation at 80°C for 1 h, the residual activity of mutant OST959 was 4.6-fold higher than that of wild-type BPO-A1. Based on the evaluation of single amino acid-substituted mutant models, stabilization of the hydrophobic core derived from P123L mutation and increased numbers of hydrogen bonds derived from G162R mutation led to higher organic solvent-stability and thermostability, respectively.

  18. Crystal Structure, Cytotoxicity and Interaction with DNA of Zinc (II Complexes with o-Vanillin Schiff Base Ligands.

    Directory of Open Access Journals (Sweden)

    Mei-Ju Niu

    Full Text Available Two new zinc complexes, Zn(HL12 (1 and [Zn2(H2L2(OAc2]2 (2 [H2L1 = Schiff base derived from o-vanillin and (R-(+-2-amino-3-phenyl-1-propanol, H3L2 = Schiff base derived from o-vanillin and 2-amino-2-ethyl-1,3-propanediol], have been synthesized and characterized by single crystal X-ray diffraction, elemental analyses, TG analyses, solid fluorescence, IR, UV-Vis and circular dichroism spectra. The structural analysis shows that complex 1 has a right-handed double helical chain along the crystallographic b axis. A homochiral 3D supramolecular architecture has been further constructed by intermolecular C-H··· π, O-H···O and C-H···O interactions. Complex 2 includes two crystallographically independent binuclear zinc molecules. The two binuclear zinc molecules are isostructural. The 2-D sheet supramolecular structure was formed by intermolecular hydrogen bonding interaction. The fluorescence of ligands and complexes in DMF at room temperature are studied. The interactions of two complexes with calf thymus DNA (CT-DNA are investigated using UV-Vis, CD and fluorescence spectroscopy. The results show that complex 1 exhibits higher interaction with CT-DNA than complex 2. In addition, in vitro cytotoxicity of the complexes towards four kinds of cancerous cell lines (A549, HeLa, HL-60 and K562 were assayed by the MTT method. Investigations on the structures indicated that the chirality and nuclearity of zinc complexes play an important role on cytotoxic activity.

  19. 搅拌棒磁子萃取-热脱附-气相色谱质谱联用分析葫芦巴浸膏的挥发性成分%Analysis of volatile components in fenugreek extract( Trigonella foenum-graecum L) by stir bar sorptive extraction-thermal desorption and gas chromatography-mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    苏勇; 冒德寿; 曲荣芬; 李智宇; 毛多斌

    2012-01-01

    Volatile components from fenugreek extract were analyzed by using stir bar soptive extraction-thermal desoption and gas chromatography-mass spectrometry,and sixty-seven compounds were identified. 1,2- propylene glycol (38.83%), 2-phenylethyl2-phenylacetate (7.32%) ,2,4-dimethy1-1,3-dioxolane-2-methanol (5.33%), rinalool (3.67%) ,2-acetoxy- 1 -propanol (3.54%), isovaleric acid (2.75%) and 2-acetylfuran (2.06%) were the main components. In addition,the flavor mechanism was discussed. The research provided technological basis for quality control and exploit of fenugreek extract.%应用搅拌棒磁子萃取和热脱附系统,并结合气相色谱-质谱联用仪,测定了葫芦巴浸膏中的挥发性成分。从中鉴定出67个挥发性物质,主要成分为:l,2-丙二醇(38.83%)、苯乙酸苯乙酯(7.32%)、羟基丙酮丙二醇缩酮(5.33%)、芳樟醇(3.67%)、丙二醇单醋酸酯(3.54%)、异戊酸(2.75%)和2-乙酰基呋喃(2.06%)。此外,对葫芦巴浸膏的致香机理进行了探讨,研究为葫芦巴浸膏的品质控制和开发应用提供了技术依据。

  20. Acompanhamento do processo de fermentação para produção de cachaça através de métodos microbiológicos e físico-químicos com diferentes isolados de Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Thaís Louise Soares

    2011-03-01

    Full Text Available Com a crescente exigência do mercado consumidor por produtos de melhor qualidade, busca-se o constante aprimoramento da produção de cachaça, uma vez que todas as etapas da cadeia produtiva de bebidas fermento-destiladas são importantes. O objetivo deste trabalho foi acompanhar o processo de fermentação para produção de cachaça, utilizando diferentes isolados de Saccharomyces cerevisiae a partir da quantificação de metabólitos secundários por Cromatografia Gasosa. O acompanhamento do processo deu-se desde o preparo do inóculo até o final do processo fermentativo. O estudo foi conduzido na Universidade Federal de Lavras (UFLA. Foram utilizados 8 isolados de Saccharomyces cerevisiae inoculados em caldo de cana, dos quais foram retiradas amostras durante a fase de crescimento em sistema de batelada alimentada e fermentação. As amostras foram analisadas quanto à taxa de floculação, ºBrix e álcoois superiores. Os parâmetros avaliados apresentaram diferenças para cada isolado. O melhor isolado para a produção de cachaça foi o isolado UFLA CA116 por apresentar alto número de células viáveis, maior taxa de floculação, ausência 1-propanol, presença de 1,3 butanediol.

  1. Odorous gaseous emissions as influence by process condition for the forced aeration composting of pig slaughterhouse sludge.

    Science.gov (United States)

    Blazy, V; de Guardia, A; Benoist, J C; Daumoin, M; Lemasle, M; Wolbert, D; Barrington, S

    2014-07-01

    Compost sustainability requires a better control of its gaseous emissions responsible for several impacts including odours. Indeed, composting odours have stopped the operation of many platforms and prevented the installation of others. Accordingly, present technologies collecting and treating gases emitted from composting are not satisfactory and alternative solutions must be found. Thus, the aim of this paper was to study the influence of composting process conditions on gaseous emissions. Pig slaughterhouse sludge mixed with wood chips was composted under forced aerationin 300 L laboratory reactors. The process conditions studied were: aeration rate of 1.68, 4.03, 6.22, 9.80 and 13.44 L/h/kg of wet sludge; incorporation ratio of 0.55, 0.83 and 1.1 (kg of wet wood chips/kg of wet sludge), and; bulking agent particles size of aeration rate and bulking agent to waste ratio: hydrogen sulphide, trimethylamine, ammonia, 2-pentanone and 1-propanol-2-methyl. However, dropping the aeration rate and increasing the bulking agent to waste ratio reduced gaseous odour emissions by a factor of 5-10, when the required threshold dilution factor ranged from 10(5) to 10(6), to avoid nuisance at peak emission rates. Process influence on emissions of dimethyl sulphide, dimethyl disulphide, dimethyl trisulphide were poorly correlated with both aeration rate and bulking agent to waste ratio as a reaction with hydrogen sulphide was suspected. Acetophenone emissions originated from the wood chips. Olfactory measurements need to be correlated to gaseous emissions for a more accurate odour emission evaluation.

  2. The same microbiota and a potentially discriminant metabolome in the saliva of omnivore, ovo-lacto-vegetarian and Vegan individuals.

    Science.gov (United States)

    De Filippis, Francesca; Vannini, Lucia; La Storia, Antonietta; Laghi, Luca; Piombino, Paola; Stellato, Giuseppina; Serrazanetti, Diana I; Gozzi, Giorgia; Turroni, Silvia; Ferrocino, Ilario; Lazzi, Camilla; Di Cagno, Raffaella; Gobbetti, Marco; Ercolini, Danilo

    2014-01-01

    The salivary microbiota has been linked to both oral and non-oral diseases. Scant knowledge is available on the effect of environmental factors such as long-term dietary choices on the salivary microbiota and metabolome. This study analyzed the microbial diversity and metabolomic profiles of the saliva of 161 healthy individuals who followed an omnivore or ovo-lacto-vegetarian or vegan diet. A large core microbiota was identified, including 12 bacterial genera, found in >98% of the individuals. The subjects could be stratified into three "salivary types" that differed on the basis of the relative abundance of the core genera Prevotella, Streptococcus/Gemella and Fusobacterium/Neisseria. Statistical analysis indicated no effect of dietary habit on the salivary microbiota. Phylogenetic beta-diversity analysis consistently showed no differences between omnivore, ovo-lacto-vegetarian and vegan individuals. Metabolomic profiling of saliva using (1)H-NMR and GC-MS/SPME identified diet-related biomarkers that enabled a significant discrimination between the 3 groups of individuals on the basis of their diet. Formate, urea, uridine and 5-methyl-3-hexanone could discriminate samples from omnivores, whereas 1-propanol, hexanoic acid and proline were characteristic of non-omnivore diets. Although the salivary metabolome can be discriminating for diet, the microbiota has a remarkable inter-individual stability and did not vary with dietary habits. Microbial homeostasis might be perturbed with sub-standard oral hygiene or other environmental factors, but there is no current indication that a choice of an omnivore, ovo-lacto-vegetarian or vegan diet can lead to a specific composition of the oral microbiota with consequences on the oral homeostasis. PMID:25372853

  3. Ruminal Fermentation of Anti-Methanogenic Nitrate- and Nitro-Containing Forages In Vitro.

    Science.gov (United States)

    Anderson, Robin C; Ripley, Laura H; Bowman, Jan G P; Callaway, Todd R; Genovese, Kenneth J; Beier, Ross C; Harvey, Roger B; Nisbet, David J

    2016-01-01

    Nitrate, 3-nitro-1-propionic acid (NPA) and 3-nitro-1-propanol (NPOH) can accumulate in forages and be poisonous to animals if consumed in high enough amounts. These chemicals are also recognized as potent anti-methanogenic compounds, but plants naturally containing these chemicals have been studied little in this regard. Presently, we found that nitrate-, NPA-, or NPOH-containing forages effectively decreased methane production, by 35-87%, during in vitro fermentation by mixed cultures of ruminal microbes compared to fermentation by cultures incubated similarly with alfalfa. Methane production was further decreased during the incubation of mixed cultures also inoculated with Denitrobacterium detoxificans, a ruminal bacterium known to metabolize nitrate, NPA, and NPOH. Inhibition of methanogens within the mixed cultures was greatest with the NPA- and NPOH-containing forages. Hydrogen accumulated in all the mixed cultures incubated with forages containing nitrate, NPA or NPOH and was dramatically higher, exceeding 40 μmol hydrogen/mL, in mixed cultures incubated with NPA-containing forage but not inoculated with D. detoxificans. This possibly reflects the inhibition of hydrogenase-catalyzed uptake of hydrogen produced via conversion of 50 μmol added formate per milliliter to hydrogen. Accumulations of volatile fatty acids revealed compensatory changes in fermentation in mixed cultures incubated with the nitrate-, NPA-, and NPOH-containing forages as evidenced by lower accumulations of acetate, and in some cases, higher accumulations of butyrate and lower accumulations of ammonia, iso-buytrate, and iso-valerate compared to cultures incubated with alfalfa. Results reveal that nitrate, NPA, and NPOH that accumulate naturally in forages can be made available within ruminal incubations to inhibit methanogenesis. Further research is warranted to determine if diets can be formulated with nitrate-, NPA-, and NPOH-containing forages to achieve efficacious mitigation in

  4. Influence of Sol-Gel Conditions on the Growth of Thiol-Functionalized Silsesquioxanes Prepared by In Situ Water Production.

    Science.gov (United States)

    Borovin, Evgeny; Callone, Emanuela; Papendorf, Benjamin; Guella, Graziano; Diré, Sandra

    2016-03-01

    Thiol-functionalized oligosilsesquioxanes have been synthesized by sol-gel chemistry via the in-situ water production (ISWP) approach, exploiting the esterification reaction of chloro-acetic acid and 1-propanol. The extent of hydrolysis-condensation of 3-Mercaptopropyltrimethoxysilane (McPTMS) has been studied by FT-IR and NMR spectroscopy, gel permeation chromatography (GPC) and MALDI-TOF techniques. The esterification reaction plays a key role in ruling out the oligomer structural development. In this work, we have investigated the influence of the theoretical amount of water available for the organosilane hydrolysis, defined by the ratio of chloro-acetic acid to McPTMS in the reaction mixture, and the role of different catalysts like trifluoroacetic acid (TFA) and dibutyldilauryltin (DBTL). The behavior of the catalyst is complex since, according to its nature, it may improve the kinetics of the sol-gel reactions and the esterification reaction as well. Comparing the reactions carried out with under-stoichiometric water content, the degree of condensation of the silsesquioxanes is higher if the reaction is catalyzed by TFA than by DBTL, because TFA may improve the kinetics of both hydrolysis-condensation and esterification reactions. The use of DBTL in under-stoichiometric and stoichiometric hydrolytic conditions raises the yield in ladder-like structures. The degree of condensation generally increases increasing the hydrolysis ratio as well as the yield in cage-like structures. However, when an over-stoichiometric amount of water is provided for the sol-gel reaction, condensation degree and ratio among cages and ladder-like structures appear unaffected by the employed catalyst. PMID:27455755

  5. Thermodynamic Stability Analysis of Tolbutamide Polymorphs and Solubility in Organic Solvents.

    Science.gov (United States)

    Svärd, Michael; Valavi, Masood; Khamar, Dikshitkumar; Kuhs, Manuel; Rasmuson, Åke C

    2016-06-01

    Melting temperatures and enthalpies of fusion have been determined by differential scanning calorimetry (DSC) for 2 polymorphs of the drug tolbutamide: FI(H) and FV. Heat capacities have been determined by temperature-modulated DSC for 4 polymorphs: FI(L), FI(H), FII, FV, and for the supercooled melt. The enthalpy of fusion of FII at its melting point has been estimated from the enthalpy of transition of FII into FI(H) through a thermodynamic cycle. Calorimetric data have been used to derive a quantitative polymorphic stability relationship between these 4 polymorphs, showing that FII is the stable polymorph below approximately 333 K, above which temperature FI(H) is the stable form up to its melting point. The relative stability of FV is well below the other polymorphs. The previously reported kinetic reversibility of the transformation between FI(L) and FI(H) has been verified using in situ Raman spectroscopy. The solid-liquid solubility of FII has been gravimetrically determined in 5 pure organic solvents (methanol, 1-propanol, ethyl acetate, acetonitrile, and toluene) over the temperature range 278 to 323 K. The ideal solubility has been estimated from calorimetric data, and solution activity coefficients at saturation in the 5 solvents determined. All solutions show positive deviation from Raoult's law, and all van't Hoff plots of solubility data are nonlinear. The solubility in toluene is well below that observed in the other investigated solvents. Solubility data have been correlated and extrapolated to the melting point using a semiempirical regression model. PMID:27238487

  6. DMSA, DMPS, and DMPA--as arsenic antidotes.

    Science.gov (United States)

    Aposhian, H V; Carter, D E; Hoover, T D; Hsu, C A; Maiorino, R M; Stine, E

    1984-04-01

    meso-Dimercaptosuccinic acid (DMSA), 2,3-dimercapto-1-propanesulfonic acid, Na salt (DMPS), and N-(2,3- dimercaptopropyl )- phthalamidic acid (DMPA) are water soluble analogs of 2,3-dimercapto-1-propanol (BAL). The relative effectiveness or therapeutic index of these dimercapto compounds in protecting mice from the lethal effects of an LD99 of sodium arsenite is DMSA greater than DMPS greater than DMPA greater than BAL in the magnitude of 42:14:4:1, respectively. DMPS, DMPA, or DMSA will mobilize tissue arsenic. BAL, however, increases the arsenic content of the brain of rabbits injected with sodium arsenite. These results raise the question as to the appropriateness of BAL as the treatment for systemic arsenic poisoning. Either DMSA or DMPS, when given sc or po, will protect rabbits against the lethal systemic effects of subcutaneously administered Lewisite . DMPS and DMSA have promise as prophylactics for the prevention of the vesicant action of Lewisite . The sodium arsenite inhibition of the pyruvate dehydrogenase (PDH) complex can be prevented and reversed in vitro or in vivo by DMPS, DMSA, DMPA, or BAL. Of them all, DMPS is most potent and BAL appears to be the least potent. The usefulness of all these dimercapto compounds would be enhanced by a careful study of their metabolism and biotransformation. These dimercapto compounds are in a great many respects orphan drugs. At this stage of their development, it is very difficult for the clinician to obtain funds to study them clinically even though they appear to be useful for treatment of poisoning by any one of the heavy metals.

  7. Development and characterization of dilutable self-microemulsifying premicroemulsion systems (SMEPMS as templates for preparation of nanosized particulates

    Directory of Open Access Journals (Sweden)

    Lin SF

    2013-09-01

    Full Text Available Shen-Fu Lin,1 Ying-Chen Chen,2 Hsiu-O Ho,2 Wei-Yu Huang,2 Ming-Thau Sheu,2,3 Der-Zen Liu1,4 1Graduate Institute of Biomedical Materials and Tissue Engineering, College of Oral Medicine, 2School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei, Taiwan; 3Clinical Research Center and Traditional Herbal Medicine Research Center, Taipei Medical University Hospital, Taipei, Taiwan; 4Center for General Education, Hsuan Chuang University, Hsinchu, Taiwan Abstract: The utilization of self-microemulsifying premicroemulsion systems (SMEPMS as templates for preparing poorly water-soluble compounds in the nanosized range represents a promising strategy. Fenofibrate was formulated with n-butyl L-lactate, Tween 80, and a number of cosurfactants (ethanol, 1-propanol, and PEG 600, diluted with the water phase (either water or saccharide solution and then subjected to a freeze-drying (FD process to obtain SMEPMS nanosized particulates. Results demonstrated that the particle size after resuspension of these FD SMEPMS nanosized particulates in water was too large, so the addition of saccharide solutions (lactose, mannitol, glucose, sucrose, and trehalose as the solid carrier to prevent particles from aggregating seemed to be necessary and workable due to steric hindrance and repulsion. However, instability of these resuspended FD nanosized particulates after 30–90 minutes still occurred, and the addition of 0.5% sodium lauryl sulfate in the resuspending medium was able to retard the aggregation and maintain the particle size within the nano-range. Evaluation by scanning electron microscopy and X-ray powder diffraction also confirmed the results. It was concluded that using an SMEPMS formulation with PEG 600 as the cosurfactant, and in the presence of a suitable saccharide as an anticaking agent and FD process were able to produce fenofibrate nanoparticles. Keywords: fenofibrate, saccharides, freeze-drying, nanoparticles

  8. Picosecond spectral relaxation of curcumin excited state in toluene–alcohol mixtures

    International Nuclear Information System (INIS)

    Excited state photophysics of Curcumin in a binary solvent mixture of toluene and five different alcohols (Methanol, Ethanol, 1-Propanol, 1-Butanol and 1-Octanol) are compared with an instrument time resolution of ∼40 ps. As the alcohol mole-fraction is varied from zero to unity, the observed trends in the fluorescence quantum yield and lifetime of the pigment in toluene–alcohol mixtures changes significantly in going from Methanol to 1-Octanol. This is attributed to the different degree of modulation of the non-radiative rates associated with the excited state intermolecular H bonding between the pigment and the alcohol. Fluorescence decays taken at the red edge of the emission spectrum started to show measurable rise times (200–30 ps) the magnitude of which decreased gradually with increasing alcohol mole-fraction. As a consequence the solvation times in the binary mixture were observed to slow down considerably at certain solvent compositions compared to that in neat alcohol. However, in toluene-1-Octanol mixture, the rise times and corresponding solvation times did not show a dependence on the 1-Octanol mole-fraction. The observed results suggest that viscosity, polarity and hydrogen bonding property of the alcohol solvent plays an important role in the excited state processes of the pigment in toluene–alcohol mixture. -- Highlights: • Excited state photophysics of Curcumin in a binary solvent mixture of toluene and five different alcohols were studied. • The observed trends in the fluorescence properties are attributed to intermolecular H bonding between the pigment and the alcohol. • Except 1-Octanol, the average solvation times of the pigment were observed to depend upon alcohol mole-fraction. • Viscosity, polarity and hydrogen bonding play an important role in the excited state processes of the pigment

  9. Measurement of nitrosamine and nitramine formation from NOx reactions with amines during amine-based carbon dioxide capture for postcombustion carbon sequestration.

    Science.gov (United States)

    Dai, Ning; Shah, Amisha D; Hu, Lanhua; Plewa, Michael J; McKague, Bruce; Mitch, William A

    2012-09-01

    With years of full-scale experience for precombustion CO(2) capture, amine-based technologies are emerging as the prime contender for postcombustion CO(2) capture. However, concerns for postcombustion applications have focused on the possible contamination of air or drinking water supplies downwind by potentially carcinogenic N-nitrosamines and N-nitramines released following their formation by NO(x) reactions with amines within the capture unit. Analytical methods for N-nitrosamines in drinking waters were adapted to measure specific N-nitrosamines and N-nitramines and total N-nitrosamines in solvent and washwater samples. The high levels of amines, aldehydes, and nitrite in these samples presented a risk for the artifactual formation of N-nitrosamines during sample storage or analysis. Application of a 30-fold molar excess of sulfamic acid to nitrite at pH 2 destroyed nitrite with no significant risk of artifactual nitrosation of amines. Analysis of aqueous morpholine solutions purged with different gas-phase NO and NO(2) concentrations indicated that N-nitrosamine formation generally exceeds N-nitramine formation. The total N-nitrosamine formation rate was at least an order of magnitude higher for the secondary amine piperazine (PZ) than for the primary amines 2-amino-2-methyl-1-propanol (AMP) and monoethanolamine (MEA) and the tertiary amine methyldiethanolamine (MDEA). Analysis of pilot washwater samples indicated a 59 μM total N-nitrosamine concentration for a system operated with a 25% AMP/15% PZ solvent, but only 0.73 μM for a 35% MEA solvent. Unfortunately, a greater fraction of the total N-nitrosamine signal was uncharacterized for the MEA-associated washwater. At a 0.73 μM total N-nitrosamine concentration, a ~25000-fold reduction in concentration is needed between washwater units and downwind drinking water supplies to meet proposed permit limits. PMID:22831707

  10. Determinação das composições físico-químicas de cachaças do sul de minas gerais e de suas misturas Determination of the physical-chemical composition of homemade cachaças produced in the South of Minas Gerais and their mixtures

    Directory of Open Access Journals (Sweden)

    Fernando José Vilela

    2007-08-01

    Full Text Available Este trabalho teve por objetivo a determinação da composição físico-química de cachaças artesanais produzidas no sul do Estado de Minas Gerais e suas misturas. Foram analisados os teores de etanol, acidez volátil, aldeídos, cobre, ésteres, álcoois superiores totais e metanol, além dos álcoois propanol-1, isobutanol e 3-metil-butanol-1. Os resultados apresentam o perfil peculiar desta bebida, que apresentou teores satisfatórios de álcoois superiores, ésteres e aldeídos. O teor de cobre apresenta-se como preocupante já que algumas amostras excederam o limite de 5 mg.L-1. A produção de misturas foi estudada e esta apresenta-se como uma alternativa viável ao produtor e cooperativas.The present study sought the physical-chemical composition of homemade cachaças produced in the south of the state Minas Gerais and of mixtures of the same cachaça samples. The ethanol, aldehyde, copper, higher alcohol, volatile acid and methanol concentrations were determined, in addition to the individual propanol, 2-methyl-1-propanol and 3-methyl-1-butanol concentrations. The results demonstrated the characteristic profile of this beverage, which presented satisfactory concentrations of higher alcohols, esters, and aldehydes. The copper concentrations of some samples exceeded the limit of 5 mg. L-1. The mixtures produced from some of the cachaça samples presented a viable alternative for the producers and cooperatives because the concentrations of the components were more adequate for exportation.

  11. Glioma cell death induced by irradiation or alkylating agent chemotherapy is independent of the intrinsic ceramide pathway.

    Directory of Open Access Journals (Sweden)

    Dorothee Gramatzki

    Full Text Available BACKGROUND/AIMS: Resistance to genotoxic therapy is a characteristic feature of glioma cells. Acid sphingomyelinase (ASM hydrolyzes sphingomyelin to ceramide and glucosylceramide synthase (GCS catalyzes ceramide metabolism. Increased ceramide levels have been suggested to enhance chemotherapy-induced death of cancer cells. METHODS: Microarray and clinical data for ASM and GCS in astrocytomas WHO grade II-IV were acquired from the Rembrandt database. Moreover, the glioblastoma database of the Cancer Genome Atlas network (TCGA was used for survival data of glioblastoma patients. For in vitro studies, increases in ceramide levels were achieved either by ASM overexpression or by the GCS inhibitor DL-threo-1-phenyl-2-palmitoylamino-3-morpholino-1-propanol (PPMP in human glioma cell lines. Combinations of alkylating chemotherapy or irradiation and ASM overexpression, PPMP or exogenous ceramide were applied in parental cells. The anti-glioma effects were investigated by assessing proliferation, metabolic activity, viability and clonogenicity. Finally, viability and clonogenicity were assessed in temozolomide (TMZ-resistant cells upon treatment with PPMP, exogenous ceramide, alkylating chemotherapy, irradiation or their combinations. RESULTS: Interrogations from the Rembrandt and TCGA database showed a better survival of glioblastoma patients with low expression of ASM or GCS. ASM overexpression or PPMP treatment alone led to ceramide accumulation but did not enhance the anti-glioma activity of alkylating chemotherapy or irradiation. PPMP or exogenous ceramide induced acute cytotoxicity in glioblastoma cells. Combined treatments with chemotherapy or irradiation led to additive, but not synergistic effects. Finally, no synergy was found when TMZ-resistant cells were treated with exogenous ceramide or PPMP alone or in combination with TMZ or irradiation. CONCLUSION: Modulation of intrinsic glioma cell ceramide levels by ASM overexpression or GCS

  12. Deuterium isotopic effects connected with unimolecular and concerted mechanisms. The case of 1-deutero-2-chloro alcohols; Effets isotopiques du deuterium attaches a des mecanismes unimoleculaires et concertes. Cas des deutero-1-chloro-2 alcools

    Energy Technology Data Exchange (ETDEWEB)

    Jambon, C

    1962-07-01

    After a bibliographic analysis of the probable causes of isotopic effects and their comparison, with the simplifications provided by the athermal model, a discussion of the isotopic effect of deuterium in organic molecules in terms of structural influences is presented, showing the important role of the C-D bond length which is shorter than the C-H bond length, and of the D atom's Van der Waals radius, shorter than that of the H atom. Kinetic measurements were carried out on some reactions involving the mechanisms proposed: unimolecular ionizations and halogen concentrates. The structural models chosen are: 2-chloro-cyclo-hexanols cis and trans 1-H and 2-D; 2-chloro-cyclo-pentanols cis trans 1-H and 1-D; 1-phenyl-l-chloro-2-propanol threo 2-H and 2-D. (author) [French] Apres une analyse bibliographique des causes probables d'effets isotopiques et leur comparaison, avec les simplifications qu'apporte le modele athermique, on a entrepris l'etude de la discussion isotopique du deuterium dans des molecules organiques en termes d'influences structurelles, cherchant a degager le role important de la longueur de la liaison C-D plus courte que C-H, et du rayon de Van der Waals de l'atome de D plus petit que celui de H. On a effectue des mesures cinetiques sur quelques reactions invoquant les mecanismes envisages: ionisations unimoleculaires et concentrees d'halogenes. Les modeles structuraux choisis sont: chloro 2 - cyclohexanols cis et trans H 1 et D 1; chloro 2 - cyclopentanols cis et trans H 1 et D 1; phenyl 1 - chloro 1 - propanol 2 threo H 2 et D 2. (auteur)

  13. Picosecond spectral relaxation of curcumin excited state in toluene–alcohol mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Saini, R.K.; Das, K., E-mail: kaustuv@rrcat.gov.in

    2013-12-15

    Excited state photophysics of Curcumin in a binary solvent mixture of toluene and five different alcohols (Methanol, Ethanol, 1-Propanol, 1-Butanol and 1-Octanol) are compared with an instrument time resolution of ∼40 ps. As the alcohol mole-fraction is varied from zero to unity, the observed trends in the fluorescence quantum yield and lifetime of the pigment in toluene–alcohol mixtures changes significantly in going from Methanol to 1-Octanol. This is attributed to the different degree of modulation of the non-radiative rates associated with the excited state intermolecular H bonding between the pigment and the alcohol. Fluorescence decays taken at the red edge of the emission spectrum started to show measurable rise times (200–30 ps) the magnitude of which decreased gradually with increasing alcohol mole-fraction. As a consequence the solvation times in the binary mixture were observed to slow down considerably at certain solvent compositions compared to that in neat alcohol. However, in toluene-1-Octanol mixture, the rise times and corresponding solvation times did not show a dependence on the 1-Octanol mole-fraction. The observed results suggest that viscosity, polarity and hydrogen bonding property of the alcohol solvent plays an important role in the excited state processes of the pigment in toluene–alcohol mixture. -- Highlights: • Excited state photophysics of Curcumin in a binary solvent mixture of toluene and five different alcohols were studied. • The observed trends in the fluorescence properties are attributed to intermolecular H bonding between the pigment and the alcohol. • Except 1-Octanol, the average solvation times of the pigment were observed to depend upon alcohol mole-fraction. • Viscosity, polarity and hydrogen bonding play an important role in the excited state processes of the pigment.

  14. Wetting transition and pretransitional thin films in binary liquids: alcohol/perfluoromethylcyclohexane mixtures studied by x-ray reflectivity

    International Nuclear Information System (INIS)

    In this study the wetting transition at the liquid-vapour interface of binary organic liquid mixtures has been investigated by x-ray reflectivity. Mixtures of various isomeric alcohols with perfluoromethylcyclohexane (PFMC) served as model systems, with alcohol carbon numbers ranging from 1 to 4. Remarkably different pretransitional behaviour of the thin films below the wetting temperature was observed, which could be classified according to the carbon number. At two-phase coexistence, no pretransitional thin films could be detected for methanol and ethanol, whereas thin-to-thick-film transitions were found for propanol and butanol and their isomers. For 1-propanol and 2-propanol, the surface of the upper, alcohol-rich phase of the gravity-separated mixture displays a wetting transition at Tw = 31.5 deg. C and 38.3 deg. C, respectively, where the thickness of a PFMC-rich film jumps from less than 25 A to values exceeding the experimental resolution of about 1200 A. For 1-butanol, 2-butanol and i-butanol, we found pretransitional film thicknesses increasing up to 100 A, with wetting transitions at Tw = 45.0 deg. C, 34.2 deg. C and 40.1 deg. C, respectively. In the single-phase region, the study of adsorption isotherms above Tw revealed novel behaviour of the adsorbed PFMC-rich film. We observed both a growing film thickness and a significantly changing composition as the coexistence line was approached. Nevertheless, the variation of the excess adsorption with distance from coexistence could still be described by a power law. (author)

  15. The same microbiota and a potentially discriminant metabolome in the saliva of omnivore, ovo-lacto-vegetarian and Vegan individuals.

    Science.gov (United States)

    De Filippis, Francesca; Vannini, Lucia; La Storia, Antonietta; Laghi, Luca; Piombino, Paola; Stellato, Giuseppina; Serrazanetti, Diana I; Gozzi, Giorgia; Turroni, Silvia; Ferrocino, Ilario; Lazzi, Camilla; Di Cagno, Raffaella; Gobbetti, Marco; Ercolini, Danilo

    2014-01-01

    The salivary microbiota has been linked to both oral and non-oral diseases. Scant knowledge is available on the effect of environmental factors such as long-term dietary choices on the salivary microbiota and metabolome. This study analyzed the microbial diversity and metabolomic profiles of the saliva of 161 healthy individuals who followed an omnivore or ovo-lacto-vegetarian or vegan diet. A large core microbiota was identified, including 12 bacterial genera, found in >98% of the individuals. The subjects could be stratified into three "salivary types" that differed on the basis of the relative abundance of the core genera Prevotella, Streptococcus/Gemella and Fusobacterium/Neisseria. Statistical analysis indicated no effect of dietary habit on the salivary microbiota. Phylogenetic beta-diversity analysis consistently showed no differences between omnivore, ovo-lacto-vegetarian and vegan individuals. Metabolomic profiling of saliva using (1)H-NMR and GC-MS/SPME identified diet-related biomarkers that enabled a significant discrimination between the 3 groups of individuals on the basis of their diet. Formate, urea, uridine and 5-methyl-3-hexanone could discriminate samples from omnivores, whereas 1-propanol, hexanoic acid and proline were characteristic of non-omnivore diets. Although the salivary metabolome can be discriminating for diet, the microbiota has a remarkable inter-individual stability and did not vary with dietary habits. Microbial homeostasis might be perturbed with sub-standard oral hygiene or other environmental factors, but there is no current indication that a choice of an omnivore, ovo-lacto-vegetarian or vegan diet can lead to a specific composition of the oral microbiota with consequences on the oral homeostasis.

  16. The same microbiota and a potentially discriminant metabolome in the saliva of omnivore, ovo-lacto-vegetarian and Vegan individuals.

    Directory of Open Access Journals (Sweden)

    Francesca De Filippis

    Full Text Available The salivary microbiota has been linked to both oral and non-oral diseases. Scant knowledge is available on the effect of environmental factors such as long-term dietary choices on the salivary microbiota and metabolome. This study analyzed the microbial diversity and metabolomic profiles of the saliva of 161 healthy individuals who followed an omnivore or ovo-lacto-vegetarian or vegan diet. A large core microbiota was identified, including 12 bacterial genera, found in >98% of the individuals. The subjects could be stratified into three "salivary types" that differed on the basis of the relative abundance of the core genera Prevotella, Streptococcus/Gemella and Fusobacterium/Neisseria. Statistical analysis indicated no effect of dietary habit on the salivary microbiota. Phylogenetic beta-diversity analysis consistently showed no differences between omnivore, ovo-lacto-vegetarian and vegan individuals. Metabolomic profiling of saliva using (1H-NMR and GC-MS/SPME identified diet-related biomarkers that enabled a significant discrimination between the 3 groups of individuals on the basis of their diet. Formate, urea, uridine and 5-methyl-3-hexanone could discriminate samples from omnivores, whereas 1-propanol, hexanoic acid and proline were characteristic of non-omnivore diets. Although the salivary metabolome can be discriminating for diet, the microbiota has a remarkable inter-individual stability and did not vary with dietary habits. Microbial homeostasis might be perturbed with sub-standard oral hygiene or other environmental factors, but there is no current indication that a choice of an omnivore, ovo-lacto-vegetarian or vegan diet can lead to a specific composition of the oral microbiota with consequences on the oral homeostasis.

  17. Excited state charge transfer reaction in (mixed solvent + electrolyte) systems: Role of reactant-solvent and reactant-ion interactions

    Indian Academy of Sciences (India)

    Harun Al Rasid Gazi; Ranjit Biswas

    2011-05-01

    Fluorescence spectroscopic techniques have been used to study the excited state intramolecular charge transfer reaction of 4-(1-azetidinyl)benzonitrile (P4C) in two sets of mixed solvents, (1-propanol + ethyl acetate) and (propylene carbonate + acetonitrile), in the absence and presence of a strong electrolyte, lithium perchlorate. These two sets of mixed solvent systems represent binary solvent mixtures of low and high polarities, respectively. Density, sound velocity and viscosity measurements indicate that these two mixed solvent systems are structurally different. Stronger ion-reactant interaction is evidenced in the mole fraction independence of emission frequencies in electrolyte solutions of low polar binary solvent mixtures. For both these mixtures, the reaction driving force (- ) decreases with increase in mole fraction of the relatively less polar solvent component of the mixture. Interestingly, - increases significantly on addition of electrolyte in low polar mixtures and exhibits mixture composition dependence but, in contrast, - in high polar mixtures does not sense variation in mixture composition in presence of electrolyte. This insensitivity to mixture composition for high polar mixtures is also observed for the measured reaction time constant. In addition, the reaction time constant does not sense the presence of electrolyte in the high polar solvent mixtures. The reaction time constant in low polar mixtures, which becomes faster on addition of electrolyte, lengthens on increasing the mole fraction of the relatively less polar solvent component of the mixture. These observations have been qualitatively explained in terms of the measured solvent reorganization energy and reaction driving force by using expressions from the classical theory of electron transfer reaction.

  18. Supporting technology for the development of Controlled Ecological Life Support Systems (CELSS)

    Science.gov (United States)

    Li, Ku-Yen; Yaws, Carl L.; Simon, William E.; Mei, Harry T.

    1995-01-01

    To support the development of Controlled Ecological Life Support Systems (CELSS) in the space program, a metabolic simulator has been selected for use in a closed chamber to test functions of the CELSS. This metabolic simulator is a catalytic reactor which oxidizes the methyl acetate to produce carbon dioxide and water vapor. In this project, kinetic studies of catalytic oxidation of methyl acetate were conducted using monolithic and pellet catalysts with 0.5% (by weight) platinum (Pt) on aluminum oxide (Al2O3). The reaction was studied at a pressure of one atmosphere and at temperatures varying from 160 C to 420 C. By-products were identified at the exit of the preheater and reactor. For the kinetic study with the monolithic catalyst, a linear regression method was used to correlate the kinetic data with zero-order, first-order and Langmuir-Hinshelwood models. Results indicate that the first-order model represents the data adequately at low concentrations of methyl acetate. For higher concentrations of methyl acetate, the Langmuir-Hinshelwood model best represents the kinetic data. Both rate constant and adsorption equilibrium constants were estimated from the regression. A Taguchi orthogonal array (L(sub 9)) was used to investigate the effects of temperature, flow rate, and concentration on the catalytic oxidation of methyl acetate. For the monolithic catalyst, temperature exerts the most significant effect, followed by concentration of methyl acetate. For the pellet catalyst, reaction temperature is the most significant factor, followed by gas flow rate and methyl acetate concentration. Concentrations of either carbon dioxide or oxygen were seen to have insignificant effect on the methyl acetate conversion process. Experimental results indicate that the preheater with glass beads can accomplish thermal cracking and catalytic reaction of methyl acetate to produce acetic acid, methanol, methyl formate, and 1-propanol. The concentration of all by-products was

  19. Porcine Sapelovirus Uses α2,3-Linked Sialic Acid on GD1a Ganglioside as a Receptor

    Science.gov (United States)

    Kim, Deok-Song; Son, Kyu-Yeol; Koo, Kyung-Min; Kim, Ji-Yun; Alfajaro, Mia Madel; Park, Jun-Gyu; Hosmillo, Myra; Soliman, Mahmoud; Baek, Yeong-Bin; Cho, Eun-Hyo; Lee, Ju-Hwan; Kang, Mun-Il

    2016-01-01

    ABSTRACT The receptor(s) for porcine sapelovirus (PSV), which causes diarrhea, pneumonia, polioencephalomyelitis, and reproductive disorders in pigs, remains largely unknown. Given the precedent for other picornaviruses which use terminal sialic acids (SAs) as receptors, we examined the role of SAs in PSV binding and infection. Using a variety of approaches, including treating cells with a carbohydrate-destroying chemical (NaIO4), mono- or oligosaccharides (N-acetylneuraminic acid, galactose, and 6′-sialyllactose), linkage-specific sialidases (neuraminidase and sialidase S), lectins (Maakia amurensis lectin and Sambucus nigra lectin), proteases (trypsin and chymotrypsin), and glucosylceramide synthase inhibitors (dl-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol and phospholipase C), we demonstrated that PSV could recognize α2,3-linked SA on glycolipids as a receptor. On the other hand, PSVs had no binding affinity for synthetic histo-blood group antigens (HBGAs), suggesting that PSVs could not use HBGAs as receptors. Depletion of cell surface glycolipids followed by reconstitution studies indicated that GD1a ganglioside, but not other gangliosides, could restore PSV binding and infection, further confirming α2,3-linked SA on GD1a as a PSV receptor. Our results could provide significant information on the understanding of the life cycle of sapelovirus and other picornaviruses. For the broader community in the area of pathogens and pathogenesis, these findings and insights could contribute to the development of affordable, useful, and efficient drugs for anti-sapelovirus therapy. IMPORTANCE The porcine sapelovirus (PSV) is known to cause enteritis, pneumonia, polioencephalomyelitis, and reproductive disorders in pigs. However, the receptor(s) that the PSV utilizes to enter host cells remains largely unknown. Using a variety of approaches, we showed that α2,3-linked terminal sialic acid (SA) on the cell surface GD1a ganglioside could be used for PSV

  20. 苯酚-间甲酚-糠醛基炭气凝胶的制备及微结构控制%Preparation and microstructure control of carbon aerogels produced using m-cresol mediated sol-gel polymerization of phenol and furfural

    Institute of Scientific and Technical Information of China (English)

    龙东辉; 张洁; 杨俊和; 胡子君; 李同起; 成果; 张睿; 凌立成

    2008-01-01

    以苯酚、间甲酚和糠醛为原料,在正丙醇溶剂中以盐酸为催化剂经溶胶-凝胶过程合成了醇凝胶,直接超临界正丙醇干燥得到有机气凝胶,在氮气保护下裂解制备出富含中孔的炭气凝胶.用IR、N2吸附、SEM、TEM等表征气凝胶的结构特征,考察了问甲酚苯酚摩尔比对凝胶结构的影响.结果发现:提高间甲酚的含量能够增强聚合物的交联密度,减小聚合物与溶剂的相溶性,缩短相分离时间,有利于得到较小的纳米颗粒和孔径的炭气凝胶.所制得的炭气凝胶平均中孔孔径随间甲酚含量的增加从47 nm逐渐减小至13 nm,BET比表面积和中孔孔容在m-C/P=0.33时达到最大值.%Carbon aerogels rich in mesopores were prepared by the sol-gel polycondensation of phenol, m-cresol, and furfural by an acid catalyst in a 1-propanol solution, followed by supercritical l-propanol drying and pyrolysis. The effect of the ratios of m-cresol to phenol (m-C/P) on the properties of aerogels was investigated. The aerogels were characte- rized by infrared spectroscopy, N2 adsorption, scanning and transmission electron microscopy. It was found that the microstructure of carbon aerogels could be adjusted by the m-C/P ratio. The average mesopore size of carbon aerogels decreased from 47 to 13 nm with increasing m-C/P ratio. The surface area calculated using the Brunauer-Emmett-Teller method, external surface area, and mesopore volume of carbon aerogels, all exhibited maxima at the m-C/P ratio of 0.33.

  1. Dip-angle influence on areal DNAPL recovery by co-solvent flooding with and without pre-flooding.

    Science.gov (United States)

    Boyd, Glen R; Li, Minghua; Husserl, Johana; Ocampo-Gómez, Ana M

    2006-01-10

    A two-dimensional (2D) laboratory model was used to study effects of gravity on areal recovery of a representative dense non-aqueous phase liquid (DNAPL) contaminant by an alcohol pre-flood and co-solvent flood in dipping aquifers. Recent studies have demonstrated that injection of alcohol and co-solvent solutions can be used to reduce in-situ the density of DNAPL globules and displace the contaminant from the source zone. However, contact with aqueous alcohol reduces interfacial tension and causes DNAPL swelling, thus facilitating risk of uncontrolled downward DNAPL migration. The 2D laboratory model was operated with constant background gradient flow and a DNAPL spill was simulated using tetrachloroethene (PCE). The spill was dispersed to a trapped, immobile PCE saturation by a water flood. Areal PCE recovery was studied using a double-triangle well pattern to simulate a remediation scheme consisting of an alcohol pre-flood using aqueous isobutanol ( approximately 10% vol.) followed by a co-solvent flood using a solution of ethylene glycol (65%) and 1-propanol (35%). Experiments were conducted with the 2D model oriented in the horizontal plane and compared to experiments at the 15 degrees and 30 degrees dip-angle orientations. Injection was applied either in the downward or upward direction of flow. Experimental results were compared to theoretical predictions for flood front stability and used to evaluate effects of gravity on areal PCE recovery. Sensitivity experiments were performed to evaluate effects of the alcohol pre-flood on PCE areal recovery. For experiments conducted with the alcohol pre-flood and the 2D model oriented in the horizontal plane, results indicate that 89-93% of source zone PCE was recovered. With injection oriented downward, results indicate that areal PCE recovery was 70-77% for a 15 degrees dip angle and 57-59% for a 30 degrees dip angle. With injection oriented upward, results indicate that areal PCE recovery was 57-60% at the 30

  2. Anti-Plasmodium activity of ceramide analogs

    Directory of Open Access Journals (Sweden)

    Gatt Shimon

    2004-12-01

    Full Text Available Abstract Background Sphingolipids are key molecules regulating many essential functions in eukaryotic cells and ceramide plays a central role in sphingolipid metabolism. A sphingolipid metabolism occurs in the intraerythrocytic stages of Plasmodium falciparum and is associated with essential biological processes. It constitutes an attractive and potential target for the development of new antimalarial drugs. Methods The anti-Plasmodium activity of a series of ceramide analogs containing different linkages (amide, methylene or thiourea linkages between the fatty acid part of ceramide and the sphingoid core was investigated in culture and compared to the sphingolipid analog PPMP (d,1-threo-1-phenyl-2-palmitoylamino-3-morpholino-1-propanol. This analog is known to inhibit the parasite sphingomyelin synthase activity and block parasite development by preventing the formation of the tubovesicular network that extends from the parasitophorous vacuole to the red cell membrane and delivers essential extracellular nutrients to the parasite. Results Analogs containing methylene linkage showed a considerably higher anti-Plasmodium activity (IC50 in the low nanomolar range than PPMP and their counterparts with a natural amide linkage (IC50 in the micromolar range. The methylene analogs blocked irreversibly P. falciparum development leading to parasite eradication in contrast to PPMP whose effect is cytostatic. A high sensitivity of action towards the parasite was observed when compared to their effect on the human MRC-5 cell growth. The toxicity towards parasites did not correlate with the inhibition by methylene analogs of the parasite sphingomyelin synthase activity and the tubovesicular network formation, indicating that this enzyme is not their primary target. Conclusions It has been shown that ceramide analogs were potent inhibitors of P. falciparum growth in culture. Interestingly, the nature of the linkage between the fatty acid part and the

  3. 溴化1-癸基-3-甲基咪唑离子液体+脂肪醇二元溶剂体系的物理化学性质%Physicochemical properties of binary mixtures {[C10 mim]Br + alcohol}

    Institute of Scientific and Technical Information of China (English)

    张云霞; 李淑妮; 翟全国; 蒋育澄; 胡满成

    2015-01-01

    The density(ρ),refractive index(nD ),and dynamic viscosity(η),for the three binary solutions containing 1-decyl-3-methylimidazolium bromide([C10 mim]Br)and fatty alcohol{ethyl-ene glycol (EG),1,2-propanediol (PG),and 1-propanol (NPA)}were investigated,respectively at temperatures of 288.15~308.15 K and under ambient pressure.Additionally,the excess molar volume(V Em ),and deviation of the refractive index(ΔnD),were calculated and correlated using the Redlich-Kister polynomial equation.The variation of density,refractive index and viscosity with the composition was described by the polynomial equations.The influence of carbon-chain length and the hydroxyl number of the fatty alcohol,and the influence of the temperature on the physi-cochemical properties of the binary systems can be explained by the comparison of the experimen-tal results.%在大气压力0.1 MPa 及288.15~308.15 K 温度下测定了溴化1-癸基-3-甲基咪唑离子液体([C10 mim]Br)+脂肪醇{乙二醇(EG)/1,2-丙二醇(PG)/正丙醇(NPA)}三个二元体系的密度(ρ)、折光率(nD )和黏度(η)。计算获得了过量摩尔体积(V Em )和折光率偏差(Δn D ),并用 Redlich-Kister 方程对衍生性质数据进行拟合。密度、折光率和黏度值随组成的变化用多项式方程进行了拟合。通过对实验数据的比较,总结出脂肪醇的碳链长度和羟基个数以及温度等对物化性质的影响。

  4. New cerium-based metal–organic scintillators for radiation detection

    Energy Technology Data Exchange (ETDEWEB)

    Boatner, L.A., E-mail: boatnerla@ornl.gov [Center for Radiation Detection Materials and Systems, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Neal, J.S. [Center for Radiation Detection Materials and Systems, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Global Nuclear Security Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Ramey, J.O. [Center for Radiation Detection Materials and Systems, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Chakoumakos, B.C. [Neutron Scattering Science Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Custelcean, R. [Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Loef, E.V.D. van; Markosyan, G.; Shah, K.S. [Radiation Monitoring Devices, Inc. Watertown, MA 02472 (United States)

    2013-03-01

    We have previously shown that a new class of scintillating materials can be developed based on the synthesis and crystal growth of rare-earth metal–organic compounds. The first scintillator of this type consisted of single crystals of CeCl{sub 3}(CH{sub 3}OH){sub 4} that were grown from a methanol solution. These crystals were shown to be applicable to both gamma-ray and fast neutron detection. Subsequently, metal–organic scintillators consisting of the compound LaBr{sub 3}(CH{sub 3}OH){sub 4} activated with varying levels of Ce{sup 3+} and of CeBr{sub 3}(CH{sub 3}OH){sub 4} were grown in single crystal form. We have now extended the development of this new class of scintillators to more complex organic components by reacting rare-earth halides such as CeCl{sub 3} or CeBr{sub 3} with different isomers of propanol and butanol—including 1-propanol, isobutanol, n-butanol, and tert-butanol. The reaction of CeCl{sub 3} or CeBr{sub 3} with these organics results in the formation of new and relatively complex molecular crystals whose structures were determined using single-crystal X-ray diffraction. These new metal–organic scintillating materials were grown in single crystal form from solution, and their scintillation characteristics have been investigated using X-ray-excited luminescence plus energy spectra obtained with gamma-ray and alpha-particle sources. If the reactions between the inorganic and organic components are not carried out under very dry and highly controlled conditions, molecular structures will be formed that incorporate waters of hydration. The present observation of scintillation in these hydrated rare-earth metal–organic compounds is apparently an original finding, since we are not aware of any previous reports of scintillation being observed in a material that incorporates waters of hydration. -- Highlights: ► New metal–organic scintillating materials were grown in single crystal form from solution. ► In two cases, molecular

  5. Alkaline phosphatase activity: new assay for the Reflotron system. Results of the evaluation in eight clinical laboratories.

    Science.gov (United States)

    Schumann, G; Dominick, H C; Hellmann, D; Klauke, R; Möckesch, M; Stekel, H; von Schenck, H; Kraft, M; Nagel, R; Hänseler, E

    2001-01-01

    A new reagent carrier, Reflotron ALP, has been developed for the Reflotron system, allowing easy and rapid measurement (in less than 3 minutes) of alkaline phosphatase (ALP) activity in capillary blood, venous blood, heparinized plasma or serum. The evaluation of the analytical performance of the assay was carried out at eight clinical laboratories. The study of the imprecision using the measurements in human samples resulted in coefficients of variation ranging from 1.3% to 4.6% (within-run) and from 3.2% to 4.0% (day-to-day). The analytical specificity of the Reflotron ALP assay agrees well with ALP methods using a N-methyl-D-glucamine buffer solution. The calibration of the Reflotron ALP assay, however, is related to the reference intervals for ALP methods using a diethanolamine buffer solution. Method comparisons were performed with the ALP method on Hitachi instruments using diethanolamine buffer. Reflotron ALP measurements in blood and plasma in 157 randomly selected split samples showed excellent agreement (slope: 0.99; intercept: 0.7 U/l; median bias: 2.3%; median difference from the comparison method: -0.3%). Specimens from pregnant women and adolescents were excluded from this study. Differing values were obtained in a method comparison using 48 samples containing predominantly the ALP bone isoform (slope: 0.81; intercept: 31.5 U/l; median bias: 5.7%; median difference from the comparison method: -12.2%). Regression analysis of the results from 21 sera with prevailing placental ALP gave a slope of 1.51, and an intercept of -41.1 U/l (median bias: 8.6%; median difference from the comparison method: 35.6%). Reflotron ALP was compared with three different wet chemistry procedures using different buffer compounds: N-methyl-D-glucamine or diethanolamine or 2-amino-2-methyl-1-propanol. In samples containing predominantly ALP isoforms not of liver origin, the measurements with N-methyl-D-glucamine buffer gave the best fit with respect to Reflotron. In an

  6. Production Techniques of Oriental Strawberry Wine & Analysis of Its Volatile Flavoring Components%东方草莓酒酿造工艺及香味成分分析

    Institute of Scientific and Technical Information of China (English)

    叶文斌; 樊亮; 宫峥嵘; 王都留

    2015-01-01

    Oriental strawberry was used as raw materials to produce oriental strawberry wine through the addition of white sugar and active dry yeast. The produced wine had special aroma. HS-SPME-GC-MS was adopted to isolate and identify the volatile flavoring components of orien-tal strawberry wine. The results suggested that, 32 kinds of volatile flavoring compounds were detected (70.72%of total volatile compounds) including 10 alcohols (64.06%of total area), and 13 esters and lactones (6.06%of total area). The mass fraction of each flavoring compound was determined by area normalizing method.The main flavoring compounds included ethanol, isoamylalcohol, 2-methyl,1-Propanol, Acetalde-hyde, 3-Methyl-1-butano, 2-Furaldehyde diethyl acetal, ethyl lactate, ethyl acetate, benzoic acid, 4-(octyloxy)-,2,5-dihydroxy-1,4-phenylene es-ter, hexadecanoic acid, and 2-methylpropyl ester, etc.%以东方草莓为原料,采用添加白砂糖、东方草莓和酿酒活性干酵母酿造东方草莓酒,发酵所得的东方草莓酒香型独特。采用顶空固相微萃取结合气相色谱-质谱联用技术(HS-SPME-GC-MS)对东方草莓酒挥发性香味成分进行分离和鉴定,结果表明,共鉴定出32种成分,占挥发性成分的70.72%,其中醇类有10种,占总面积的64.06%;酯类和内酯种类有13种,占总面积的6.06%,并用面积归一化法测定了各种成分的质量分数,其主要成分为:乙醇、3-甲基-1-丁醇、异戊醇、2-甲基丙醇、正丙醇、2-呋喃甲醛缩二乙醇、乙缩醛二乙醇;乳酸乙酯、乙酸乙酯、苯甲酸-4-辛氧基-2,5二羟基-1,4亚苯基酯、十六酸2-甲基丙酯等。

  7. Slow oxidation of acetoxime and methylethyl ketoxime to the corresponding nitronates and hydroxy nitronates by liver microsomes from rats, mice, and humans.

    Science.gov (United States)

    Völkel, W; Wolf, N; Derelanko, M; Dekant, W

    1999-02-01

    Acetoxime and methylethyl ketoxime (MEKO) are tumorigenic in rodents, inducing liver tumors in male animals. The mechanisms of tumorigenicity for these compounds are not well defined. Oxidation of the oximes to nitronates of secondary-nitroalkanes, which are mutagenic and tumorigenic in rodents, has been postulated to play a role in the bioactivation of ketoximes. In these experiments, we have compared the oxidation of acetoxime and methylethyl ketoxime to corresponding nitronates in liver microsomes from different species. The oximes were incubated with liver microsomes from mice, rats, and several human liver samples. After tautomeric equilibration and extraction with n-hexane, 2-nitropropane and 2-nitrobutane were quantitated by GC/MS-NCI (limit of detection of 250 fmol/injection volume). In liver microsomes, nitronate formation from MEKO and acetoxime was dependent on time, enzymatically active proteins, and the presence of NADPH. Nitronate formation was increased in liver microsomes of rats pretreated with inducers of cytochrome P450 and reduced in the presence of inhibitors (n-octylamine and diethyldithiocarbamate). Rates of oxidation of MEKO (Vmax) were 1.1 nmol/min/mg (mice), 0.5 nmol/min/mg (humans), and 0.1 nmol/min/mg (rats). In addition to nitronates, several minor metabolites were also enzymatically formed (two diastereoisomers of 3-nitro-2-butanol, 2-hydroxy-3-butanone oxime and 2-nitro-1-butanol). Acetoxime was also metabolized to the corresponding nitronate at rates approximately 50% of those observed with MEKO oxidation in the three species examined. 2-Nitro-1-propanol was identified as a minor product formed from acetoxime. No sex differences in the capacity to oxidize acetoxime and MEKO were observed in the species examined. The observed results show that formation of sec-nitronates from ketoximes occurs slowly, but is not the only pathway involved in the oxidative biotransformation of these compounds. Due to the lack of sex-specific oxidative

  8. Photochemical ozone creation potentials for oxygenated volatile organic compounds: sensitivity to variations in kinetic and mechanistic parameters

    Science.gov (United States)

    Jenkin, Michael E.; Hayman, Garry D.

    The sensitivity of Photochemical Ozone Creation Potentials (POCP) to a series of systematic variations in the rates and products of reactions of radical intermediates and oxygenated products is investigated for the C 4 alcohols, 1-butanol ( n-butanol) and 2-methyl-1-propanol ( i-butanol), using the recently developed Master Chemical Mechanism (MCM) as the base case. The POCP values are determined from the calculated formation of ozone in the boundary layer over a period of approximately five days along an idealised straight line trajectory, using a photochemical trajectory model and methodology described in detail previously. The results allow the relative impacts on calculated ozone formation of various classes of chemical reaction within the degradation chemistry to be assessed. The calculated POCP is found to be very insensitive to many of the changes investigated. However, it is found to be sensitive to variations in the rate coefficient for the initiating reaction with OH ( kOH), although the sensitivity decreases with increasing kOH. The POCP appears to vary approximately linearly with kOH at low values (i.e. kOH less than ca. 4×10 -13 cm 3 molecule -1 s -1), whereas at high reactivities (i.e. kOH greater than ca. 4×10 -11 cm 3 molecule -1 s -1), the calculated POCP value is comparatively insensitive to the precise value of kOH. The POCP is also very sensitive to mechanistic changes which influence the yields of unreactive oxygenated products (i.e. those with OH reactivities below ca. 10 -12 cm 3 molecule -1 s -1), for example acetone. The propensity of the organic compound to produce organic nitrates (which act as comparatively unreactive reservoirs for free radicals and NO x) also appears to have a notable influence on the calculated POCP. Recently reported information relevant to the degradation of oxygenated VOCs is then used to update the chemical schemes for the 17 alcohols and glycols, 10 ethers and glycol ethers, and 8 esters included in the MCM

  9. Facile synthesis of new nano sorbent for magnetic solid-phase extraction by self assembling of bis-(2,4,4-trimethyl pentyl)-dithiophosphinic acid on Fe{sub 3}O{sub 4}-Ag core-shell nanoparticles: Characterization and application

    Energy Technology Data Exchange (ETDEWEB)

    Tahmasebi, Elham [Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran (Iran, Islamic Republic of); Yamini, Yadollah, E-mail: yyamini@modares.ac.ir [Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran (Iran, Islamic Republic of)

    2012-12-05

    Graphical abstract: Self assembling of bis-(2,4,4-trimethylpentyl)-dithiophosphinic acid on Fe{sub 3}O{sub 4}-Ag core-shell nanoparticles and application of it for solid phase extraction of PAHs. Highlights: Black-Right-Pointing-Pointer A novel sorbent for magnetic solid-phase extraction of PAHs was introduced. Black-Right-Pointing-Pointer Silver was coated on Fe{sub 3}O{sub 4} nanoparticles (MNPs) by reduction of AgNO{sub 3} with NaBH{sub 4}. Black-Right-Pointing-Pointer Bis-(2,4,4-trimethylpentyl)-dithiophosphinic acid self-assembled on silver coated MNPs. Black-Right-Pointing-Pointer Size, morphology, composition and properties of the nanoparticles were characterized. Black-Right-Pointing-Pointer Extraction efficiency of the sorbent was investigated by extraction of five PAHs. - Abstract: A novel sorbent for magnetic solid-phase extraction by self-assembling of organosulfur compound, (bis-(2,4,4-trimethylpentyl)-dithiophosphinic acid), onto the silver-coated Fe{sub 3}O{sub 4} nanoparticles was introduced. Due to the formation of covalent bond of S-Ag, the new coating on the silver surface was very stable and showed high thermal stability (up to 320 Degree-Sign C). The size, morphology, composition, and properties of the prepared nanoparticles have also been characterized and determined using scanning electron microscopy (SEM), energy-dispersive X-ray analyzer (EDX), dynamic light scattering (DLS), Fourier transform-infrared (FT-IR) spectroscopy, and thermal gravimetric analysis (TGA). Extraction efficiency of the new sorbent was investigated by extraction of five polycyclic aromatic hydrocarbons (PAHs) as model compounds. The optimum extraction conditions for PAHs were obtained as of extraction time, 20 min; 50 mg sorbent from 100 mL of the sample solution, and elution with 100 {mu}L of 1-propanol under fierce vortex for 2 min. Under the optimal conditions, the calibration curves were obtained in the range of 0.05-100 {mu}g L{sup -1} (R{sup 2} > 0.9980) and the

  10. Facile synthesis of new nano sorbent for magnetic solid-phase extraction by self assembling of bis-(2,4,4-trimethyl pentyl)-dithiophosphinic acid on Fe3O4-Ag core-shell nanoparticles: Characterization and application

    International Nuclear Information System (INIS)

    Graphical abstract: Self assembling of bis-(2,4,4-trimethylpentyl)-dithiophosphinic acid on Fe3O4-Ag core-shell nanoparticles and application of it for solid phase extraction of PAHs. Highlights: ► A novel sorbent for magnetic solid-phase extraction of PAHs was introduced. ► Silver was coated on Fe3O4 nanoparticles (MNPs) by reduction of AgNO3 with NaBH4. ► Bis-(2,4,4-trimethylpentyl)-dithiophosphinic acid self-assembled on silver coated MNPs. ► Size, morphology, composition and properties of the nanoparticles were characterized. ► Extraction efficiency of the sorbent was investigated by extraction of five PAHs. - Abstract: A novel sorbent for magnetic solid-phase extraction by self-assembling of organosulfur compound, (bis-(2,4,4-trimethylpentyl)-dithiophosphinic acid), onto the silver-coated Fe3O4 nanoparticles was introduced. Due to the formation of covalent bond of S-Ag, the new coating on the silver surface was very stable and showed high thermal stability (up to 320 °C). The size, morphology, composition, and properties of the prepared nanoparticles have also been characterized and determined using scanning electron microscopy (SEM), energy-dispersive X-ray analyzer (EDX), dynamic light scattering (DLS), Fourier transform-infrared (FT-IR) spectroscopy, and thermal gravimetric analysis (TGA). Extraction efficiency of the new sorbent was investigated by extraction of five polycyclic aromatic hydrocarbons (PAHs) as model compounds. The optimum extraction conditions for PAHs were obtained as of extraction time, 20 min; 50 mg sorbent from 100 mL of the sample solution, and elution with 100 μL of 1-propanol under fierce vortex for 2 min. Under the optimal conditions, the calibration curves were obtained in the range of 0.05–100 μg L−1 (R2 > 0.9980) and the LODs (S/N = 3) were obtained in the range of 0.02–0.10 μg L−1. Relative standard deviations (RSDs) for intra- and inter-day precision were 2.6–4.2% and 3.6–8.3%, respectively. In

  11. NaBr, NaCl和KBr在几种有机溶剂中活度系数的测定%Activity Coefficient Measurement of NaBr, NaCl and KBr in Selected Organic Solvents

    Institute of Scientific and Technical Information of China (English)

    姜波; 王利生; 李弥异

    2011-01-01

    In this paper, the conductivities of NaBr in methanol, ethanol, 1-propanol, 2-propanol, NaC1 and KBr in methanol, ethanol system (solution concentration within 0. 1 mol· L-1 ) were determined at 298.15 K, 313.15 K and 323.15 K at atmosphere pressure respectively. The mean ion activity coefficients of NaBr, NaC1 and KBr in various organic solvents were calculated according to DebyeHacker limiting law and Onsager-Falkenhangen equations. The effects of concentration and temperature on activity coefficients of electrolyte solutions were discussed. The calculated results were compared with those of NaBr in ethanol, NaC1 in methanol and KBr in methanol reported in literature. The results show that the experimental data obtained by conductivity method have good agreement with data in literature.%分别测定了NaBr在甲醉、乙醇、正丙醉和异丙醇中,NaCI和KBr在甲醉和乙醉中共8个体系(溶液物质的量的浓度在0.1 mol·L(-1)范围内)在298.15,313.15和323.15 K下的电导率,利用Debye-Hiicker和Osager-Falkenhangen公式计算了以上溶液体系的平均离子活度系数,讨论了浓度和温度对电解质溶液活度系数的影响.其中NaBr在乙醇中,NaCI在甲醉中和KBr在甲醇中的平均离子活度系数的计算结果与已发表文献中的数据进行了比较.结果表明,该方法的活度系数结果与文献数据有较好的一致性.

  12. Lactivibrio alcoholicus gen. nov., sp. nov., an anaerobic, mesophilic, lactate-, alcohol-, carbohydrate- and amino-acid-degrading bacterium in the phylum Synergistetes.

    Science.gov (United States)

    Qiu, Yan-Ling; Hanada, Satoshi; Kamagata, Yoichi; Guo, Rong-Bo; Sekiguchi, Yuji

    2014-06-01

    A mesophilic, obligately anaerobic, lactate-, alcohol-, carbohydrate- and amino-acid- degrading bacterium, designated strain 7WAY-8-7(T), was isolated from an upflow anaerobic sludge blanket reactor treating high-strength organic wastewater from isomerized sugar production processes. Cells of strain 7WAY-8-7(T) were motile, curved rods (0.7-1.0×5.0-8.0 µm). Spore formation was not observed. The strain grew optimally at 37 °C (range for growth was 25-40 °C) and pH 7.0 (pH 6.0-7.5), and could grow fermentatively on yeast extract, glucose, ribose, xylose, malate, tryptone, pyruvate, fumarate, Casamino acids, serine and cysteine. The main end-products of glucose fermentation were acetate and hydrogen. In co-culture with the hydrogenotrophic methanogen Methanospirillum hungatei DSM 864(T), strain 7WAY-8-7(T) could utilize lactate, glycerol, ethanol, 1-propanol, 1-butanol, L-glutamate, alanine, leucine, isoleucine, valine, histidine, asparagine, glutamine, arginine, lysine, threonine, 2-oxoglutarate, aspartate and methionine. A Stickland reaction was not observed with some pairs of amino acids. Yeast extract was required for growth. Nitrate, sulfate, thiosulfate, elemental sulfur, sulfite and Fe (III) were not used as terminal electron acceptors. The G+C content of the genomic DNA was 61.4 mol%. 16S rRNA gene sequence analysis revealed that the isolate belongs to the uncultured environmental clone clade (called 'PD-UASB-13' in the Greengenes database) in the bacterial phylum Synergistetes, showing less than 90% sequence similarity with closely related described species such as Aminivibrio pyruvatiphilus and Aminobacterium colombiense (89.7% and 88.7%, respectively). The major cellular fatty acids were iso-C(13 : 0), iso-C(15 : 0), anteiso-C(15 : 0), C(18 : 1), C(19 : 1), C(20 : 1) and C(21 : 1). A novel genus and species, Lactivibrio alcoholicus gen. nov., sp. nov. is proposed to accommodate strain 7WAY-8-7(T) ( = JCM 17151(T

  13. Regulation of SREBPs by Sphingomyelin in Adipocytes via a Caveolin and Ras-ERK-MAPK-CREB Signaling Pathway.

    Directory of Open Access Journals (Sweden)

    Nehman Makdissy

    Full Text Available Sterol response element binding protein (SREBP is a key transcription factor in insulin and glucose metabolism. We previously demonstrated that elevated levels of membrane sphingomyelin (SM were related to peroxisome proliferator-activated receptor-γ (PPARγ, which is a known target gene of SREBP-1 in adipocytes. However, the role of SM in SREBP expression in adipocytes remains unknown. In human abdominal adipose tissue from obese women with various concentrations of fasting plasma insulin, SREBP-1 proteins decreased in parallel with increases in membrane SM levels. An inverse correlation was found between the membrane SM content and the levels of SREBP-1c/ERK/Ras/PPARγ/CREB proteins. For the first time, we demonstrate the effects of SM and its signaling pathway in 3T3-F442A adipocytes. These cells were enriched or unenriched with SM in a range of concentrations similar to those observed in obese subjects by adding exogenous natural SMs (having different acyl chain lengths or by inhibiting neutral sphingomyelinase. SM accumulated in caveolae of the plasma membrane within 24 h and then in the intracellular space. SM enrichment decreased SREBP-1 through the inhibition of extracellular signal-regulated protein kinase (ERK but not JNK or p38 mitogen-activated protein kinase (MAPK. Ras/Raf-1/MEK1/2 and KSR proteins, which are upstream mediators of ERK, were down-regulated, whereas SREBP-2/caveolin and cholesterol were up-regulated. In SM-unmodulated adipocytes treated with DL-1-Phenyl-2-Palmitoylamino-3-morpholino-1-propanol (PPMP, where the ceramide level increased, the expression levels of SREBPs and ERK were modulated in an opposite direction relative to the SM-enriched cells. SM inhibited the insulin-induced expression of SREBP-1. Rosiglitazone, which is an anti-diabetic agent and potent activator of PPARγ, reversed the effects of SM on SREBP-1, PPARγ and CREB. Taken together, these findings provide novel insights indicating that excess

  14. Insights on alterations to the rumen ecosystem by nitrate and nitrocompounds

    Directory of Open Access Journals (Sweden)

    Elizabeth eLatham

    2016-03-01

    Full Text Available Nitrate and certain short chain nitrocompounds and nitro-oxy compounds are being investigated as dietary supplements to reduce economic and environmental costs associated with ruminal methane emissions. Thermodynamically, nitrate is a preferred electron acceptor in the rumen that consumes electrons at the expense of methanogenesis during dissimilatory reduction to an intermediate, nitrite, which is primarily reduced to ammonia although small quantities of nitrous oxide may also be produced. Short chain nitrocompounds act as direct inhibitors of methanogenic bacteria although certain of these compounds may also consume electrons at the expense of methanogenesis and are effective inhibitors of important foodborne pathogens. Microbial and nutritional consequences of incorporating nitrate into ruminant diets typically results in increased acetate production. Unlike most other methane-inhibiting supplements, nitrate decreases or has no effect on propionate production. The type of nitrate salt added influences rates of nitrate reduction, rates of nitrite accumulation and efficacy of methane reduction, with sodium and potassium salts being more potent than calcium nitrate salts. Digestive consequences of adding nitrocompounds to ruminant diets are more variable and may in some cases increase propionate production. Concerns about the toxicity of nitrate’s intermediate product, nitrite, to ruminants necessitate management, as animal poisoning may occur via methemoglobinemia. Certain of the naturally occurring nitrocompounds, such as 3-nitro-1-propionate or 3-nitro-1-propanol also cause poisoning but via inhibition of succinate dehydrogenase. Typical risk management procedures to avoid nitrite toxicity involve gradually adapting the animals to higher concentrations of nitrate and nitrite, which could possibly be used with the nitrocompounds as well. A number of organisms responsible for nitrate metabolism in the rumen have been characterized. To date a

  15. Insights on Alterations to the Rumen Ecosystem by Nitrate and Nitrocompounds.

    Science.gov (United States)

    Latham, Elizabeth A; Anderson, Robin C; Pinchak, William E; Nisbet, David J

    2016-01-01

    Nitrate and certain short chain nitrocompounds and nitro-oxy compounds are being investigated as dietary supplements to reduce economic and environmental costs associated with ruminal methane emissions. Thermodynamically, nitrate is a preferred electron acceptor in the rumen that consumes electrons at the expense of methanogenesis during dissimilatory reduction to an intermediate, nitrite, which is primarily reduced to ammonia although small quantities of nitrous oxide may also be produced. Short chain nitrocompounds act as direct inhibitors of methanogenic bacteria although certain of these compounds may also consume electrons at the expense of methanogenesis and are effective inhibitors of important foodborne pathogens. Microbial and nutritional consequences of incorporating nitrate into ruminant diets typically results in increased acetate production. Unlike most other methane-inhibiting supplements, nitrate decreases or has no effect on propionate production. The type of nitrate salt added influences rates of nitrate reduction, rates of nitrite accumulation and efficacy of methane reduction, with sodium and potassium salts being more potent than calcium nitrate salts. Digestive consequences of adding nitrocompounds to ruminant diets are more variable and may in some cases increase propionate production. Concerns about the toxicity of nitrate's intermediate product, nitrite, to ruminants necessitate management, as animal poisoning may occur via methemoglobinemia. Certain of the naturally occurring nitrocompounds, such as 3-nitro-1-propionate or 3-nitro-1-propanol also cause poisoning but via inhibition of succinate dehydrogenase. Typical risk management procedures to avoid nitrite toxicity involve gradually adapting the animals to higher concentrations of nitrate and nitrite, which could possibly be used with the nitrocompounds as well. A number of organisms responsible for nitrate metabolism in the rumen have been characterized. To date a single rumen bacterium

  16. Analysis of Aroma Components in Three Species of Jiefangzhong Dry Loquat Wine%3种解放钟干型枇杷酒香气成分分析

    Institute of Scientific and Technical Information of China (English)

    张丽萍; 黄鹭强; 杨民和

    2012-01-01

    The aromatic components in three Jiefangzhong dry Loquat wines from differ-ent winery were compared using headspacesolid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS). Results showed the three wines all had the aromatic components of Phenylethyl Alcohol, 2-methyl-1-Propanol, Butanedioic acid-diethyl ester, Benzoic acid-ethyl ester. There are little Propanoicacid-2-hydroxy-ethyl ester, Benze-neacetic acid-ethyl ester, Sorbic acid. Some variance exist in Loquat wines from different winery which main lie in both variety of aromatic components and relative contents; 1-Bu-tano1-3-methyl-formate, Ethyl Acetate, Hexanoic acid-ethyl ester were detected in the A Lo-quat wine. Heptanoic acid-butyl ester, Decanoic acid-ethyl ester, 1-Hexanol were detected in the B Loquat wine. Octanoic acid-ethyl ester, Methoxyacetic acid-pentyl ester, 2-Furan-methanol were detected in the C Loquat wine. To some extent, the differences of aromatic components created diversities of flavor and taste.%采用顶空固相微萃取技术,结合气质联用对3种不同产地的解放钟干型枇杷酒的香气成分进行检测分析.结果表明,3种不同产地的解放钟干型枇杷酒均含有苯乙醇、异丁醇、丁二酸二乙酯、苯甲酸乙酯等,同时还含有少量的乳酸乙酯、苯乙酸乙酯、山梨酸等.不同产地枇杷酒香气成分的种类及相对含量存在一定的差异:A型枇杷酒中含量相对较高的有甲酸异戊酯、乙酸乙酯、己酸乙酯等;B型枇杷酒中的特征性香气成分包括庚酸丁酯、癸酸乙酯、正己醇等;C型枇杷酒含有辛酸乙酯、甲氧乙酸戊酯、糠醇等.香气成分的差异赋予了解放钟干型枇杷酒独特的风味及口感.

  17. Molecular analysis of volatile metabolites released specifically by staphylococcus aureus and pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Filipiak Wojciech

    2012-06-01

    Full Text Available Abstract Background The routinely used microbiological diagnosis of ventilator associated pneumonia (VAP is time consuming and often requires invasive methods for collection of human specimens (e.g. bronchoscopy. Therefore, it is of utmost interest to develop a non-invasive method for the early detection of bacterial infection in ventilated patients, preferably allowing the identification of the specific pathogens. The present work is an attempt to identify pathogen-derived volatile biomarkers in breath that can be used for early and non- invasive diagnosis of ventilator associated pneumonia (VAP. For this purpose, in vitro experiments with bacteria most frequently found in VAP patients, i.e. Staphylococcus aureus and Pseudomonas aeruginosa, were performed to investigate the release or consumption of volatile organic compounds (VOCs. Results Headspace samples were collected and preconcentrated on multibed sorption tubes at different time points and subsequently analyzed with gas chromatography mass spectrometry (GC-MS. As many as 32 and 37 volatile metabolites were released by S. aureus and P. aeruginosa, respectively. Distinct differences in the bacteria-specific VOC profiles were found, especially with regard to aldehydes (e.g. acetaldehyde, 3-methylbutanal, which were taken up only by P. aeruginosa but released by S. aureus. Differences in concentration profiles were also found for acids (e.g. isovaleric acid, ketones (e.g. acetoin, 2-nonanone, hydrocarbons (e.g. 2-butene, 1,10-undecadiene, alcohols (e.g. 2-methyl-1-propanol, 2-butanol, esters (e.g. ethyl formate, methyl 2-methylbutyrate, volatile sulfur compounds (VSCs, e.g. dimethylsulfide and volatile nitrogen compounds (VNCs, e.g. 3-methylpyrrole. Importantly, a significant VOC release was found already 1.5 hours after culture start, corresponding to cell numbers of ~8*106 [CFUs/ml]. Conclusions The results obtained provide strong evidence that the detection and perhaps even

  18. Thermodynamics of Organic Compound Alteration in Hydrothermal Systems

    Science.gov (United States)

    Shock, E. L.

    2005-12-01

    Organic compounds enter hydrothermal systems through infiltrating surface waters, zones of microbial productivity in the subsurface, extracts of organic matter in surrounding host rocks, and abiotic synthesis. Owing to variations in pH, oxidation state, composition, temperature, and pressure throughout the changing pathways of fluid migration over the duration of the system, organic compounds from all of these sources are introduced to conditions where their relative stabilities and reactivities can be dramatically transformed. If those transformations were predictable, then the extent to which organic alteration reactions have occurred could be used to reveal flowpaths and histories of hydrothermal systems. Speciation and mass transfer calculations permit some insight into the underlying thermodynamic driving forces that result in organic compound alteration. As an example, the speciation of many geochemist's canonical organic matter: CH2O depends strongly on oxidation state, temperature, and total concentration of dissolved organic matter. Calculations show that at oxidation states buffered by iron-bearing mineral assemblages, organic acids dominate the speciation of CH2O throughout hydrothermal systems, with acetic acid (itself equivalent to 2 CH2O by bulk composition) and propanoic acid generally the most abundant compounds. However, at more reduced conditions, which may prevail in organic-rich iron-poor sediments, the drive is to form ketones and especially alcohols at the expense of organic acids. The distribution of organic carbon among the various members of these compound classes is strongly dependent on the total concentration of dissolved organic matter. As an example, at a bulk concentration equivalent to average dissolved organic matter in seawater (45μm), the dominant alcohols at 100°C are small compounds like ethanol and 1-propanol. In contrast, at a higher bulk concentration of 500μm, there is a drive to shift large percentages of dissolved

  19. Extraction and Analysis Volatile Constituents of Dry Yellow Soybean Sauce by Steam Distillation and GC-MS%水蒸气蒸馏结合气质联机分析干黄酱中挥发性成分

    Institute of Scientific and Technical Information of China (English)

    刘永国; 穆旻; 苗志伟; 韩帅

    2013-01-01

    The volatile constituents of two kinds of dry yellow soybean sauce from Beijing are extracted by steam distillation in order to analyze their volatile compositions.The extraction conditions are optimized in order to obtain better extraction conditions.The extractives are analyzed by gas chromatography-mass spectrometry,combined with calculation of retention index about the separated constituents.Thirty-eight compounds are identified,including 4 alcohols,2 phenols,10 aldehydes,2 ketones,10 organic acids,7 esters and 3 other compounds.Their relative contents are determined by peak area normalization method.There are 2 0 compounds which are common constituents in two kinds of dry yellow soybean sauce; they are ethanol,2-methyl-1-propanol,2-furanmethanol,5-methyl-2-furanmethanol,2-methoxy-4-vinylphenol,2-methyl-propanal,3-methyl-butanal,furfural,benzeneac-etaldehyde,5-methyl-2-phenyl-2-hexenal,methyl vinyl ketone,acetic acid,propanoic acid,2-methylpropanoic acid,4-methylpentanoic acid,octanoic acid,n-hexadecanoic acid,ethyl formate,ethyl acetate,1-(1H-pyrrol-2-yl)-ethanone.%采用水蒸气蒸馏的方法对产于北京的两种干黄酱中的挥发性成分进行了提取,为了得到较佳的提取条件,对提取条件进行了优化.所得提取物经气相色谱-质谱联用仪分析,结合计算分离出的成分的保留指数,共鉴定出38种成分,其中醇类4种、酚类2种、醛类10种、酮类2种、酸类10种、酯类7种、其他3种;采用面积归一化法确定了它们的相对含量.两种干黄酱中都鉴定出的挥发性成分有20种,分别是乙醇、2-甲基丙醇、糠醇、5-甲基糠醇、4-乙烯基愈创木酚、2-甲基丙醛、3-甲基丁醛、糠醛、苯乙醛、5-甲基-2-苯基-2-己烯醛、甲基乙烯基酮、乙酸、丙酸、2-甲基丙酸、4-甲基戊酸、辛酸、十六酸、甲酸乙酯、乙酸乙酯、2-乙酰基吡咯.

  20. A calorimetric and equilibrium investigation of the reaction {l_brace}methyl ferulate(aq) + H{sub 2}O(l) = methanol(aq) + ferulic acid(aq){r_brace}

    Energy Technology Data Exchange (ETDEWEB)

    Goldberg, Robert N., E-mail: robert.goldberg@nist.go [Biochemical Science Division, National Institute of Standards and Technology, Gaithersburg, MD 20876 (United States); Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore, MD 21250 (United States); Lang, Brian E., E-mail: brian.lang@nist.go [Biochemical Science Division, National Institute of Standards and Technology, Gaithersburg, MD 20876 (United States); Selig, Michael J., E-mail: michael.selig@nrel.go [National Renewable Energy Laboratory, Biosciences Center, 1617 Cole Boulevard, Golden, CO 80401 (United States); Decker, Stephen R., E-mail: steve.decker@nrel.go [National Renewable Energy Laboratory, Biosciences Center, 1617 Cole Boulevard, Golden, CO 80401 (United States)

    2011-03-15

    Microcalorimetry and high-performance liquid chromatography (HPLC) have been used to conduct a thermodynamic investigation of the reaction: {l_brace}methyl ferulate(aq) + H{sub 2}O(l) = methanol(aq) + ferulic acid(aq){r_brace}, as catalyzed by feruloyl esterase. Values of the apparent equilibrium constant K' = (29.6 {+-} 0.7) (T = 298.15 K, citrate buffer at pH 4.98, ionic strength I = 0.39 mol {center_dot} kg{sup -1}) and of the calorimetrically determined enthalpy of reaction {Delta}{sub r}H(cal) = (4.0 {+-} 0.9) kJ {center_dot} mol{sup -1} (T = 298.15 K and citrate buffer at pH 4.81, I = 0.36 mol {center_dot} kg{sup -1}) were measured. A chemical equilibrium model, together with pKs and standard enthalpies of reaction {Delta}{sub r}H{sup 0} for the H{sup +}(aq) binding reactions of the reactants and products, was then used to calculate the values K = (1.89 {+-} 0.06) . 10{sup -4}, {Delta}{sub r}H{sup o} = (7.3 {+-} 1.7) kJ {center_dot} mol{sup -1}, {Delta}{sub r}G{sup o} = (21.25 {+-} 0.07) kJ {center_dot} mol{sup -1}, and {Delta}{sub r}S{sup o} = - (46.8 {+-} 5.7) J {center_dot} K{sup -1} {center_dot} mol{sup -1} for the chemical reference reaction {l_brace}methyl ferulate(aq) + H{sub 2}O(l) = methanol(aq) + ferulic acid{sup -}(aq) + H{sup +}(aq){r_brace}. These values of K and {Delta}{sub r}H{sup o} are similar in magnitude to the corresponding values reported for the reaction {l_brace}propyl gallate(aq) + H{sub 2}O(l) = 3,4,5-trihydroxybenzoic acid{sup -}(aq) + 1-propanol(aq) + H{sup +}(aq){r_brace}. The results obtained in this study can be used in a chemical equilibrium model to calculate how K' and other standard transformed properties such as the standard transformed enthalpy {Delta}{sub r}H'{sup o}, standard transformed Gibbs free energy {Delta}{sub r}G'{sup o}, and the change in binding of H{sup +}(aq), {Delta}{sub r}N(H{sup +}), vary with the independent variables T, pH, and I.

  1. The promotional effects of cesium promoter on higher alcohol synthesis from syngas over cesium-promoted Cu/ZnO/Al2O3 catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jie; Cai, Qiuxia; Wan, Yan; Wan, Shaolong; Wang, Li; Lin, Jingdong; Mei, Donghai; Wang, Yong

    2016-09-02

    In this study, the promotional effects of cesium promoter on higher alcohol (C2+OH) synthesis from syngas over Cs-Cu/ZnO/Al2O3 catalysts were investigated using a combined experimental and theoretical density functional theory (DFT) calculation method. In the presence of cesium, the C2+OH productivity increases from 77.1 g•kgcat-1•h-1 to 157.3 g•kgcat-1•h-1 at 583 K due to the enhancement of the initial C–C bond formation. Detailed analysis of chain growth probabilities (CGPs) confirms that initial C–C bond formation is the rate-determining step in the temperature range of 543-583 K. Addition of cesium promoter significantly increases the productivities of 2-methyl-1-propanol, while the CGPs values (C3* to 2-methyl-C3*) is almost unaffected. With the assistance of cesium promoter, the CGPs of the initial C–C bond formation step (C1* to C2*) could be increased from 0.13 to 0.25 at 583 K. DFT calculations indicate that the initial C–C bond formation is mainly contributed by the HCO+HCO coupling reaction over the ZnCu(211) model surface. In the presence of the Cs2O, the stabilities of key reaction intermediates such as HCO and H2CO are enhanced which facilitates both HCO+HCO and HCO+H2CO coupling reaction steps with lower activation barriers over the Cs2O-ZnCu(211) surface. The promotional effects of cesium on the C2+OH productivity are also benefited from the competitive CH+HCO coupling reaction over CH hydrogenation that leads to lower alkane formation. In addition, Bader charge analysis suggests that the presence of cesium ions would facilitate the nucleophilic reaction between HCO and H2CO for initial C–C bond formation. This work was supported by the National Natural Science Foundation of China (No. 91545114 and No. 91545203). We appreciate the joint PhD scholarship support from the China Scholarship Council. The authors would also like to thank the support from Collaborative Innovation Center of Chemistry for Energy Materials (2011-iChEM). DM

  2. Green LPG

    Energy Technology Data Exchange (ETDEWEB)

    Hulteberg, Christian; Brandin, Jan; Leveau, Andreas (Biofuel-Solution AB, Limhamn (Sweden))

    2010-12-15

    readily available as the production of biofuels (from which glycerine is a side product) in the world has increased markedly over the last 10 year period. This glut in the glycerol production has also lowered worldwide prices of glycerine. Since the key step in producing energy gases from glycerol is the dehydration of glycerol to acrolein, this step has attracted much attention during the development work. The step has been improved during the performed work and the need for any regeneration of the catalyst has been significantly reduced, if not omitted completely. This improvement allows for a simple fixed bed reactor design and will save cost in reactor construction as well as in operating costs of the plant. The same conclusion can be drawn from the combination of the two functionalities (dehydration and hydrogenation) in designing a catalyst that promote the direct reaction of 1-propanol to propane in one step instead of two. The experiments with the decarbonylation of acrolein to form ethane show that the catalyst deactivation rates are quite rapid. The addition of noble metal to the catalyst seems to improve the longevity of the catalyst, but the coking is still too severe to provide for a commercially viable process. It is believed that there is a possible way forward for the decarbonylation of acrolein to ethane; it will however require additional time and resources spent in this area. In this work it has been shown that all of the catalytic steps involved in the production of propane from glycerol have sufficient longterm stability and endurance and it is motivated to recommend that the project continues to pilot plant testing stage

  3. Oxygenates vs. synthesis gas

    Energy Technology Data Exchange (ETDEWEB)

    Kamil Klier; Richard G. Herman; Alessandra Beretta; Maria A. Burcham; Qun Sun; Yeping Cai; Biswanath Roy

    1999-04-01

    Methanol synthesis from H{sub 2}/CO has been carried out at 7.6 MPa over zirconia-supported copper catalysts. Catalysts with nominal compositions of 10/90 mol% and 30/70 mol% Cu/ZrO{sub 2} were used in this study. Additionally, a 3 mol% cesium-doped 10/90 catalyst was prepared to study the effect of doping with heavy alkali, and this promoter greatly increased the methanol productivity. The effects of CO{sub 2} addition, water injection, reaction temperature, and H{sub 2}/C0 ratio have been investigated. Both CO{sub 2} addition to the synthesis gas and cesium doping of the catalyst promoted methanol synthesis, while inhibiting the synthesis of dimethyl ether. Injection of water, however, was found to slightly suppress methanol and dimethyl ether formation while being converted to CO{sub 2} via the water gas shift reaction over these catalysts. There was no clear correlation between copper surface area and catalyst activity. Surface analysis of the tested samples revealed that copper tended to migrate and enrich the catalyst surface. The concept of employing a double-bed reactor with a pronounced temperature gradient to enhance higher alcohol synthesis was explored, and it was found that utilization of a Cs-promoted Cu/ZnO/Cr{sub 2}O{sub 3} catalyst as a first lower temperature bed and a Cs-promoted ZnO/Cr{sub 2}O{sub 3} catalyst as a second high-temperature bed significantly promoted the productivity of 2-methyl-1-propanol (isobutanol) from H{sub 2}/CO synthesis gas mixtures. While the conversion of CO to C{sub 2+} oxygenates over the double-bed configuration was comparable to that observed over the single Cu-based catalyst, major changes in the product distribution occurred by the coupling to the zinc chromite catalyst; that is, the productivity of the C{sub 1}-C{sub 3} alcohols decreased dramatically, and 2-methyl branched alcohols were selectively formed. The desirable methanol/2-methyl oxygenate molar ratios close to 1 were obtained in the present double

  4. The Production of Biodiesel from Cottonseed Oil Using Rhizopus oryzae Whole Cell Biocatalysts

    Science.gov (United States)

    Athalye, Sneha Kishor

    accumulation of 15.6 g (dry cell wt)/L. A reduction in dynamic viscosity of the reaction mixture from 47.3 centipoise to 30.6 centipoise was observed. The impact of moisture addition to the reaction mixture and use of ethanol as acylating agent on R.oryzae BSP fatty acid alkyl ester production was also tested. The presence of 10 wt % moisture in the reaction system had a significant effect (p ≤ 0.05) on the transesterification reaction with ethanol unlike methanol. Fatty acid ethyl ester concentration tripled from 39.3 to 129.1 g/L when moisture was added during transesterification .When oil to acyl acceptor ratio was increased from 1:3 and 1:6 to determine effect of excess alcohol on conversion, an ester conversion of 128.1 g/L for methanol and 129.1 g/L for ethanol were observed. Use of excess amount of acylating agent had a significant adverse effect (p ≤ 0.05) on the overall FAAE production due to deactivation of lipases on contact with large amounts of insoluble alcohol in the oil phase of the reaction. The effect of short chain alcohols on the enzymatic transesterification of cottonseed oil using freeze dried Rhizopus oryzae biomass was examined with and without water addition using methanol, ethanol, 1-Propanol and 1-Butanol at various molar ratios. 1- Butanol in the absence of water resulted in a significantly higher (p . 0.1) conversion of cottonseed oil to 12.5 % fatty acid butyl esters (FABEs). Addition of 10 % water to the reaction mixture significantly reduced (p ≤ 0.1) conversion. No significant difference (p > 0.1) between the conversions was observed for time points after 24 h for a 72 h reaction. 1- Butanol in ratios higher than 3:1 to cottonseed oil had a significant impact (p ≤ 0.1) on conversion. Increasing the amount of biomass used during the reaction lead to significantly higher conversion (p ≤ 0.1). The highest conversion of 27.9 % was observed for the transesterification reaction between cottonseed oil and 1-Butanol, in a 1:6 molar ratio, in

  5. Oxy-combustion of high water content fuels

    Science.gov (United States)

    Yi, Fei

    As the issues of global warming and the energy crisis arouse extensive concern, more and more research is focused on maximizing energy efficiency and capturing CO2 in power generation. To achieve this, in this research, we propose an unconventional concept of combustion - direct combustion of high water content fuels. Due to the high water content in the fuels, they may not burn under air-fired conditions. Therefore, oxy-combustion is applied. Three applications of this concept in power generation are proposed - direct steam generation for the turbine cycle, staged oxy-combustion with zero flue gas recycle, and oxy-combustion in a low speed diesel-type engine. The proposed processes could provide alternative approaches to directly utilize fuels which intrinsically have high water content. A large amount of energy to remove the water, when the fuels are utilized in a conventional approach, is saved. The properties and difficulty in dewatering high water content fuels (e.g. bioethanol, microalgae and fine coal) are summarized. These fuels include both renewable and fossil fuels. In addition, the technique can also allow for low-cost carbon capture due to oxy-combustion. When renewable fuel is utilized, the whole process can be carbon negative. To validate and evaluate this concept, the research focused on the investigation of the flame stability and characteristics for high water content fuels. My study has demonstrated the feasibility of burning fuels that have been heavily diluted with water in a swirl-stabilized burner. Ethanol and 1-propanol were first tested as the fuels and the flame stability maps were obtained. Flame stability, as characterized by the blow-off limit -- the lowest O2 concentration when a flame could exist under a given oxidizer flow rate, was determined as a function of total oxidizer flow rate, fuel concentration and nozzle type. Furthermore, both the gas temperature contour and the overall ethanol concentration in the droplets along the