Sample records for 1-pentanol 2-pentanol 3-pentanol

  1. Binary total pressure measurements for methanol with 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, 2-methyl-2-butanol, 3-methyl-1-butanol, and 3-methyl-2-butanol at 313.15 K

    SciTech Connect

    Barton, D.P.; Bhethanabotla, V.R.; Campbell, S.W. [Univ. of South Florida, Tampa, FL (United States). Dept. of Chemical Engineering] [Univ. of South Florida, Tampa, FL (United States). Dept. of Chemical Engineering

    1996-09-01

    Total pressure measurements at 313.15 K are reported for binary systems of methanol with each of seven pentanol isomers: 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, 2-methyl-2-butanol, 3-methyl-1-butanol, and 3-methyl-2-butanol. The results were obtained using a Van Ness apparatus and were fitted to the four-suffix Margules equation using Barker`s method. The four-suffix Margules equation represents the data to within an average of approximately 0.02 kPa.

  2. Acoustic and volumetric studies of binary mixtures of 1,3-butanediol + 1-pentanol

    NASA Astrophysics Data System (ADS)

    Zor?bski, E.

    2006-11-01

    The results of acoustic and volumetric investigations of binary liquid mixtures of 1,3-butanediol with 1-pentanol at the temperatures (298.15, 308.15, and 318.15)?K are presented. Basing on the phase speed of ultrasound values (measured by the pulse-echo-overlap method at 2.18?MHz) and densities, the excess values of the molar volume and isentropic compressibility (volume-specific and molar), were calculated. Their composition dependencies were expressed by Redlich-Kister polynomials. It turned out that mixing of 1,3-butanediol with 1-pentanol, results in an enhanced rigidity of the mixtures in comparison with that of the pure components. What is more, this rigidity increases with increasing temperature. At the same time the volume effects (expansion) upon mixing increase with increasing temperature too. The results are discussed in terms of the variations of the structure and molecular interactions.

  3. Enantioselective acylation of R-2-pentanol in a solid/gas reactor catalysed by lipase B from Candida antarctica.

    E-print Network

    Paris-Sud XI, Université de

    that there is no effect of the organic solvent on the enantioselectivity E of CALB for this reaction neither in the solid in enantioselective synthetic reactions. Among the most used lipases for synthesis or resolution of racemates, lipaseReview Copy Enantioselective acylation of R-2-pentanol in a solid/gas reactor catalysed by lipase B

  4. Exploring the discrepancies between experiment, theory, and simulation for the homogeneous gas-to-liquid nucleation of 1-pentanol

    NASA Astrophysics Data System (ADS)

    Nellas, Ricky B.; Keasler, Samuel J.; Siepmann, J. Ilja; Chen, Bin

    2010-04-01

    Using an efficient Monte Carlo approach known as Aggregation-Volume-bias Monte Carlo with self-adaptive Umbrella Sampling and Histogram Reweighting (AVUS-HR), we obtained the nucleation free energy profile of 1-pentanol at various temperatures from 220 to 360 K. From these profiles, differences between the free energy barrier heights obtained from our simulations and those predicted by the classical nucleation theory (CNT) were calculated. Our results strongly support that the logarithm of the nucleation rate ratio between simulation (or experiment) and CNT increases almost linearly with the inverse temperature. Among the various factors that contribute to the discrepancy between simulation and CNT nucleation rates, the nonzero surface free energy of the monomer included in the CNT makes the largest contribution. On the molecular level, the simulations indicate that a gas-phase cluster of 1-pentanol molecules is relatively compact and can contain multiple hydrogen bonded aggregates of various sizes and that this aggregate size distribution depends strongly on temperature and also on the overall size of the cluster system.

  5. Kinetic resolution of rac -2-pentanol catalyzed by Candida antarctica lipase B in the ionic liquid, 1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]amide

    Microsoft Academic Search

    Marilyne Noël; Pedro Lozano; Michel Vaultier; José L. Iborra

    2004-01-01

    The ionic liquid, 1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]amide ([Bmim] [NTf2]), was used as a reaction medium for the kinetic resolution of rac-2-pentanol catalyzed by free Candida antarctica lipase B, using vinyl propionate at 2% (v\\/v) water content. The synthetic activity of lipase in [Bmim] [NTf2] was up 2.5-times greater than in hexane, and showed high enantioselectivity (ee > 99.99%). The optimal temperature and pH

  6. Synthesis and application of a bidentate ligand based on decafluoro-3-phenyl-3-pentanol: steric effect of pentafluoroethyl groups on the stereomutation of O-equatorial C-apical spirophosphoranes.

    PubMed

    Jiang, Xin-Dong; Kakuda, Ken-ichiro; Matsukawa, Shiro; Yamamichi, Hideaki; Kojima, Satoshi; Yamamoto, Yohsuke

    2007-02-01

    1,1,1,2,2,4,4,5,5,5-Decafluoro-3-phenyl-3-pentanol was prepared by a Cannizzaro-type disproportionation reaction, and the dimetallated compound was used as a bidentate ligand, which is bulkier than the Martin ligand (1,1,1,3,3,3-hexafluoro-2-phenyl-2-propanol). A P-H spirophosphorane was synthesized by utilizing the new bidentate ligand, and the structure of the product was essentially the same as that of the P-H phosphorane with Martin ligands. Phosphoranes that exhibit reversed apicophilicity (O-equatorial) were also synthesized and could be converted into the corresponding stable stereoisomers (O-apical). The crystal structures of O-equatorial phosphoranes and the O-apical isomers were slightly affected by the steric repulsion of pentafluoroethyl groups. Kinetic measurements revealed that the stereomutation of O-equatorial methylphosphorane to the O-apical isomer was slowed. The activation enthalpy for the stereomutation of the former to the latter was higher than that of the phosphorane with Martin ligands by 5.1 kcal mol(-1). PMID:17441167

  7. Composition and Process for Retarding the Premature Aging of PMR Monomer Solutions and PMR Prepegs

    NASA Technical Reports Server (NTRS)

    Alston, William B. (Inventor); Gahn, Gloria S. (Inventor)

    2000-01-01

    Polyimides are derived from solutions of at least one low-boiling organic solvent, e.g. isopropanol containing a mixture of polyimide-forming monomers. The monomeric solutions have an extended shelf life at ambient (room) temperatures as high as 80 C, and consist essentially of a mixture of monoalkyl ester-acids, alkyl diester-diacids and aromatic polyamines wherein the alkyl radicals of the esteracids are derived from lower molecular weight aliphatic secondary alcohols having 3 to 5 carbon atoms per molecule such as isopropanol, secondary butanol, 2-methyl-3-butanol, 2 pentanol or 3-pentanol. The solutions of the polyimide-forming monomers have a substantially improved shelf-life and are particularly useful in the aerospace and aeronautical industry for the preparation of polyimide reinforced fiber composites such as the polyimide cured carbon composites used in jet engines, missiles, and for other high temperature applications.

  8. Preyssler catalyst, [NaP 5W 30O 110] 14?: A green, efficient and reusable catalyst for esterification of salicylic acid with aliphatic and benzylic alcohols

    Microsoft Academic Search

    Fatemeh F. Bamoharram; Majid M. Heravi; Mina Roshani; Manochehr Jahangir; Ali Gharib

    2006-01-01

    A series of eco-friendly solid acid catalysts, including H14[NaP5W30O110], H14–P5, H14[NaP5W29MoO110], H14–P5Mo, and silica supported H14[NaP5W30O110], H14–P5\\/SiO2 have been used as catalysts for esterification of salicylic acid with aliphatic alcohols (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, t-butanol, 1-pentanol, and 2-pentanol) and benzylic alcohols (benzyl, 2-methylbenzyl, 2-chlorobenzyl, 4-bromobenzyl, 3-nitrobenzyl, and 4-methoxy benzyl) alcohol.The performance of different forms of Preyssler's anion in the

  9. Formation of the metabolic intermediate 2,4,4-trimethyl-2-pentanol during incubation of a shape Sphingomonas sp. strain with the xeno-estrogenic octylphenol

    Microsoft Academic Search

    Tom Tanghe; Willem Dhooge; Willy Verstraete

    2000-01-01

    Degradation of branched octylphenol was studied in abacterial culture of a Sphingomonas sp. strain.Octylphenol is considered to be the most stabledegradation intermediate formed from the correspondingnonionic octylphenol polyethoxylates surfactantsduring biological wastewater treatment. Sinceoctylphenol can exert estrogenic effects in wildlife,a detailed study of its biodegradation is warranted.The aerobic microbiological transformation ofoctylphenol was examined with and without the additionof the easily assimilable

  10. Matrix effects on the photocatalytic oxidation of alcohols by [nBu4N]4W10O32 incorporated into sol-gel silica.

    PubMed

    Molinari, Alessandra; Bratovcic, Amra; Magnacca, Giuliana; Maldotti, Andrea

    2010-09-01

    Two heterogeneous photocatalysts have been prepared by entrapment of [nBu(4)N](4)W(10)O(32) in a silica matrix, through a sol-gel procedure: SiO(2)/W30% and SiO(2)/W10% with 30% and 10% of decatungstate, respectively. They are characterized by the presence of micropores of about 7 A and 15 A and mesopores of about 25 A. Due to different preparation procedures, SiO(2)/W10% presents a more remarkable porous network than SiO(2)/W30%. The morphological features of SiO(2)/W30% and SiO(2)/W10% differ from those of their parent material SiO(2)/W0%, indicating that incorporation of the decatungstate induces a significant modification of the porous texture of the siliceous material. These photocatalysts demonstrate good stability in the oxygen-assisted photooxidation of 1-pentanol and 3-pentanol, which have been chosen as models of primary and secondary aliphatic alcohols. In particular, photoexcitation (lambda > 290 nm, 25 degrees C, 760 torr of O(2)) leads to conversion of these two substrates to pentanal or 3-pentanone, with a mass balance of about 90%. There is a strong effect of the solid support on the reactivity of the two alcoholic substrates. In particular, oxidation of 1-pentanol with SiO(2)/W10% is about four times faster than with [nBu(4)N](4)W(10)O(32) in homogeneous solution. Preferential adsorption phenomena, due to the hydrophilic character of silica explain the photocatalytic properties of the two heterogeneous systems, because adsorption favours the contact between the photoexcited decatungstate and the primary OH group of 1-pentanol. Moreover, some kind of shape selectivity, due to the microporous structure of the investigated materials, likely contributes to control the conversion yields. PMID:20657929

  11. Determination of alcohol solvent orientation and bonding at silver electrodes using surface-enhanced Raman scattering: Methanol, ethanol, 1-propanol, and 1-pentanol

    SciTech Connect

    Sobocinski, R.L.; Pemberton, J.E. [Univ. of Arizona, Tucson, AZ (United States)

    1992-08-01

    Interfacial solvent structure at Ag electrodes in various straight-chain alcohol electrolyte systems has been studied using surface-enhanced Raman scattering (SERS). SERS provides detailed information regarding the nature of interfacial bonding and alkyl chain orientation. Methanol appears to be in a unique hydrogen-bonding environment at the interface, as indicated by a 10-cm{sup -1} decrease in v(C-O) frequency from its bulk solution value; C{sub 2} and longer chain alcohols at the interface show no shift in v(C-O) frequency from bulk solution. The alkyl chains are largely parallel to the surface (i.e., greater than 45{degrees} relative to the surface normal) and exist in a largely all-trans configuration at electrode potentials positive of the PZC (potential of zero charge). These molecules are oriented with the hydroxyl group at the surface and the alkyl chain tilted slightly away from the surface. At more negative potentials near the PZC, the alkyl chain conformations become more disordered, and the alkyl chains {open_quotes}stand up{close_quotes}, with the methyl group directed into bulk solution. For methanol, two distinct orientations exist simultaneously at the interface in the vicinity of the PZC. The growth of a new methylene band for C{sub 2}, C{sub 3}, and C{sub 5} alcohols at increasingly negative potentials suggests significant interaction of the methylene hydrogens with the surface. In contrast to the C{sub 3} and C{sub 5} alcohols, the C{sub 1} and C{sub 2} alcohols exhibit little bulk spectroscopic behavior, indicating distinct orientations at potentials negative of the PZC. All observations support the idea that the {alpha}-carbon is confined near the surface at all potentials for all four alcohols. The driving force for this behavior is proposed to be the formation of C-H Ag agostic bonds.

  12. JASPERSE CHEM 360 TEST 1 VERSION 3 Reactions involving Alcohols

    E-print Network

    Jasperse, Craig P.

    1 JASPERSE CHEM 360 TEST 1 VERSION 3 Reactions involving Alcohols 1. 2-Methyl-3-pentanol is classified as: (3 points) a. a primary alcohol b. a secondary alcohol c. a tertiary alcohol d. none;6 10. Design syntheses of the following, starting from alcohols of 4 carbons. (7 points each) O #12;

  13. Preparation of 2-Bromopentane.

    ERIC Educational Resources Information Center

    Howell, B. A.; Kohrman, R. E.

    1984-01-01

    Suggests that the preparation of 2-bromopentane from 2-pentanol might represent an instructive addition to a published description of pheromone synthesis in that it is economical, extends the synthetic nature of the problem, and amplifies the mechanistic vagaries of the substitution reaction. Theory, procedures used, and safety considerations are…

  14. Direct Observation of Two-Dimensional Electron Solvation at Alcohol/Ag(111) Interfaces S. H. Liu, A. D. Miller, K. J. Gaffney, P. Szymanski, S. Garrett-Roe, I. Bezel, and

    E-print Network

    Harris, Charles B.

    -dimensional electron solvation by methanol, 1-propanol, 1-butanol, and 1-pentanol overlayers on a Ag(111) surface to the rotation of the adsorbate molecular dipoles to solvate the electron. This rotation lowers the electron reflect the reorganization of molecules adsorbed on a metal surface. We present results for methanol, 1

  15. Aggregation Pheromones and Host Kairomones of West Indian Sugarcane Weevil, Metamasius hemipterus sericeus

    Microsoft Academic Search

    A. L. Perez; Y. Campos; C. M. Chinchilla; A. C. Oehlschlager; G. Gries; R. Gries; R. M. Giblin-Davis; G. Castrillo; J. E. Peña; R. E. Duncan; L. M. Gonzalez; R. McDonald; R. Andrade

    1997-01-01

    Coupled gas chromatographic–electroantennographic detection (GC-EAD) analyses and coupled GC-mass spectrometry (MS) of volatiles produced by male and female West Indian sugarcane weevils (WISW), Metamasius hemipterus sericeus (Oliv.), revealed eight male specific, EAD-active compounds: 3-pentanol (1), 2-methyl-4-heptanol (2), 2-methyl-4-octanol (3), 4-methyl-5-nonanol (4), and the corresponding ketones. In field experiments in Florida, alcohols 1–4 in combination with sugarcane were most attractive, whereas

  16. Heat capacity of associated systems. Experimental data and application of a two-state model to pure liquids and mixtures.

    PubMed

    Cerdeiriña, Claudio A; Troncoso, Jacobo; Gonzalez-Salgado, Diego; García-Miaja, Gonzalo; Hernandez-Segura, Gerardo O; Bessières, David; Medeiros, Milton; Romaní, Luis; Costas, Miguel

    2007-02-01

    The predictions from a recently reported (J. Chem. Phys. 2004, 120, 6648) two-state association model (TSAM) have been tested against experimental data. The temperature, T, and pressure, p, dependence of the isobaric heat capacity, C(p), for three pure alcohols and the temperature dependence at atmospheric pressure of the excess heat capacity, C(p)(E), for four alcohol + ester mixtures have been measured. The branched alcohols were 3-pentanol, 3-methyl-3-pentanol, and 3-ethyl-3-pentanol, and the mixtures were 1-butanol and 3-methyl-3-pentanol mixed with propyl acetate and with butyl formate. These data, together with literature data for alcohol + n-alkane and alcohol + toluene mixtures, have been analyzed using the TSAM. The model, originally formulated for the C(p) of pure liquids, has been extended here to account for the C(p)(E) of mixtures. To evaluate its performance, quantum mechanical ab initio calculations for the H-bond energy, which is one of the model parameters, were performed. The effect of pressure on C(p) for pure liquids was elucidated, and the variety of C(p)(E)(T) behaviors was rationalized. Furthermore, from the C(p) data at various pressures, the behavior of the volume temperature derivative, (deltaV/deltaT)(p), was inferred, with the existence of a (deltaV/deltaT)(p) versus T maximum for pure associated liquids such as the branched alcohols being predicted. It is concluded that the TSAM captures the essential elements determining the behavior of the heat capacity for pure liquids and mixtures, providing insight into the macroscopic manifestation of the association phenomena occurring at the molecular level. PMID:17266265

  17. Influence of ?-lactoglobulin, pH and presence of other aroma compounds on the air\\/liquid partition coefficients of 20 aroma compounds varying in functional group and chain length

    Microsoft Academic Search

    Saskia M. van Ruth; Elise Villeneuve

    2002-01-01

    The air\\/water partition coefficients of 20 aroma compounds varying in functional group and chain length were determined as a function of ?-lactoglobulin concentration (0, 0.5, 0.7, 1.0, 2.0%), pH (3, 6, 9) and presence of other aroma compounds in the matrix. Air\\/liquid partition coefficients of dimethyl sulphide, 1-propanol, diacetyl, 2-butanone, ethyl acetate, 1-butanol, 2-pentanol, propyl acetate, 3-methyl-1-butanol, ethyl butyrate, hexanal,

  18. Spectrophotometric assay for ornithine decarboxylase.

    PubMed

    Ngo, T T; Brillhart, K L; Davis, R H; Wong, R C; Bovaird, J H; Digangi, J J; Ristow, J L; Marsh, J L; Phan, A P; Lenhoff, H M

    1987-02-01

    A rapid and sensitive spectrophotometric assay for ornithine decarboxylase is described. It is based on the observation that the product of ornithine decarboxylase, putrescine, reacts with 2,4,6-trinitrobenzenesulfonic acid to give a colored product soluble in 1-pentanol whereas ornithine does not. The amount of putrescine produced by the enzyme was determined by measuring the absorbance of the 1-pentanol extract of the reaction mixture at 420 nm, and by comparing the results to those obtained by the trapping of 14CO2 and by HPLC assays. The three assays were found to be equivalent in sensitivity, with the spectrophotometric assay having the advantages of being relatively rapid, requiring only common laboratory equipment, and not requiring the use of radioactive isotopes. PMID:3578755

  19. QUATERNARY LIQUID EQULIBRIUM : WATER—PHOSPHORIC ACID—1— PENTANONE AT 25° C

    Microsoft Academic Search

    JOSE M. MARCO; MARIA L GALAN; JOSE COSTA

    1988-01-01

    Liquid-liquid equilibrium, solubility and tie-line data, for the quaternary system Water-Phosphoric Acid-l-Pentanol-3-Pentanone, were obtained at 25°C and atmospheric pressure, using an analytical method. 1-Pentanol appears to be more effective than 3-Pentanone as extractant solvent of phosphoric acid. Advantages are not observed with the use of mixed solvents in the purification of wet process phosphoric acid by means of solvent extraction.

  20. Catalytic coupling of carboxylic acids by ketonization as a processing step in biomass conversion

    Microsoft Academic Search

    Christian A. Gaertner; Juan Carlos Serrano-Ruiz; Drew J. Braden; James A. Dumesic

    2009-01-01

    Carboxylic acids, common intermediate products in biomass conversion processes, can be converted into ketones via ketonization reactions over a ceria–zirconia catalyst. Reaction kinetics studies were carried out using hexanoic acid, as a representative carboxylic acid, in the presence of 1-pentanol and 2-butanone, as representative biomass-derived alcohol and ketone species. Studies were carried out at temperatures from 448 to 623K, and

  1. Molecular interaction of alcohols with acrylic esters in non-polar solvents

    Microsoft Academic Search

    K. Dharmalingam; K. Ramachandran; P. Sivagurunathan; G. M. Kalamse

    2006-01-01

    The molecular interaction between alcohols (1-propanol, 1-pentanol, 1-heptanol, and 1-octanol) and acrylic esters (methyl methacrylate (MMA), ethyl methacrylate (EMA) and butyl methacrylate (BMA)) have been studied in carbon tetrachloride and benzene at 298 K using dielectric and FTIR spectroscopic methods. The result shows that, 1:1 complex is predominant in these systems. The strength of hydrogen bond (O–H:C=O) formation shows a significant

  2. Molecular interactions in alcohol–ethyl methacrylate mixtures

    Microsoft Academic Search

    K. Dharmalingam; K. Ramachandran; P. Sivagurunathan; G. M. Kalamse

    2008-01-01

    Molecular interaction between alcohols (1-propanol, 1-butanol, s-butanol, t-butanol, 1-pentanol, 1-heptanol, 1-octanol and 1-decanol) with ethyl methacrylate has been studied in n-heptane, CCl4 and benzene at 298K using FTIR spectroscopic and dielectric methods. The result obtained from both the methods indicates only the existence of most likely 1:1 complex formation between the alcohol and ethyl methacrylate in these systems. The alkyl

  3. FTIR and dielectric studies of molecular interaction between alkyl methacrylates and primary alcohols

    Microsoft Academic Search

    K. Dharmalingam; K. Ramachandran; P. Sivagurunathan

    2007-01-01

    The molecular interaction between alkyl methacrylates (methyl methacrylate, ethyl methacrylate and butyl methacrylate) and primary alcohols (1-propanol, 1-butanol, 1-pentanol, 1-heptanol, 1-octanol and 1-decanol) has been studied in carbon tetrachloride by FTIR spectroscopic and dielectric methods. The results show that the most likely association between alcohol and ester is 1:1 complex through the free hydroxyl group of the alcohol and the

  4. Dielectric Relaxation Study of Amide-Alcohol Mixtures by Using Time Domain Reflectometry

    Microsoft Academic Search

    K. Ramachandran; P. Sivagurunathan; K. Dharmalingam; S. C. Mehrotra

    2007-01-01

    Using time domain reflectometry (TDR), dielectric relaxation studies were carried out on binary mixtures of amides (N-methylformamide (NMF) and N,N-dimethylformamide (DMF)) with alcohols (1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, and 1-decanol) for various concentrations over the frequency range from 10 MHz to 10 GHz at 303 K. The Kirkwood correlation factor and excess dielectric constant properties were determined and discussed to

  5. Enhancement of critical heat flux in subcooled flow boiling of water by use of a volatile additive

    SciTech Connect

    Pabisz, R.A. Jr.; Bergles, A.E. [Rensselaer Polytechnic Inst., Troy, NY (United States). Heat Transfer Lab.

    1996-12-31

    The present investigation considers the effect of a 1-pentanol additive in water on the critical heat flux (CHF) and pressure drop in forced subcooled boiling. A small quantity of 1-pentanol was added to distilled water with the objective of getting an approximate 2% by weight mixture, which had been found to give superior performance in previous studies of pool and flow boiling. Experiments were performed using stainless steel tubes with internal diameters of 4.4 and 6.1 mm. Tests were conducted with mass fluxes of 4,400 kg/m{sup 2}s, exit pressures of 9 bar, length-to-diameter ratios of 25, and exit subcoolings from 65 to 90 C. Test sections were heated directly by DC power, and critical heat flux data were inferred from test-section burnout. The alcohol concentration was periodically checked by draining off a sample and performing a Proton Nuclear Magnetic Resonance scan on the mixture. At high subcoolings, the mixture exhibited an increase in the critical heat flux over that of pure water. However at low subcoolings there is a decrease in the critical heat flux. The increases in critical heat flux noted with the 1-pentanol mixture in this experiment were not as large as would be expected from saturated pool boiling results published by Van Stralen (1959). Pressure drop data for both the mixture and the pure water also were recorded. The 1-pentanol mixture, in general, exhibited larger pressure drops for the same conditions. Subcooled flow boiling has a wide array of commercial cooling applications, including blades in gas turbines, high power laser optics, plasma-facing components in fusion reactors, supercomputers, etc.

  6. A rhodamine-deoxylactam based sensor for chromo-fluorogenic detection of nerve agent simulant.

    PubMed

    Wu, Zhisheng; Wu, Xuanjun; Yang, Yuhui; Wen, Ting-bin; Han, Shoufa

    2012-10-15

    N-(rhodamine B)-deoxylactam-5-amino-1-pentanol (dRB-APOH) was designed and prepared as the chromo-fluorogenic sensor for detection of a nerve agent simulant via analyte triggered tandem phosphorylation and opening of the intramolecular deoxylactam. The successful detection of diethyl chlorophosphate suggests the utility of rhodamine-deoxylactams as the chromo-fluorogenic signal reporting platform for design of sensors targeting reactive chemical species via various chemistries. PMID:22995618

  7. Partial molal expansibilities of organic compounds in aqueous solution. I. Alcohols and ethers

    Microsoft Academic Search

    Sergio Cabani; Giovanni Conti; Enrico Matteoli

    1976-01-01

    The temperature dependence of limiting apparent molal volumes F°? in water for some alcohols (methanol, ethanol, 1-propanol, 2-butanol, 3-pentanol, 3-hexanol, 2,5-hexanediol, cyclopentanol, cyclohexanol, cycloheptanol, and 1,4-cyclohexanediol) and ethers (trimethylene oxide, tetrahydrofuran, tetrahydropyran, 1,3-dioxolane, 1,3-dioxane, 1,4-dioxane, 1,3-dioxepane, 1,3,5-trioxane, dimethoxymethane, 1,2-dimethoxyethane, diethoxymethane, and diethyl ether) has been studied in the temperature range 10–50°C by means of an automatic digital-readout dilatometer. Values of

  8. Direct gas chromatography for the study of substrate removal kinetics in multi-component aqueous systems

    E-print Network

    Langley, William Douglas

    1966-01-01

    -Butyl Acetate. 18. Removal of 1-Butanol. 19. Removal of 1-Pentanol. Page . 58 61 62 63 64 65 20. Test Ai Organic Component Removal Syringe Filtered Aqueous Phase. ~ 79 21. Test Ai Organic Substrate Removal. 81. 22. Test B: Organic Component Removal... and chemical processes as well as for various other research and control applications (12). Zn a separate paper, he presented the results of his evaluation of activated carbon adsorption of n-butanol and amyl acetate from aqueous solutions as measured...

  9. The Effect of Cavitating Ultrasound on the Heterogeneous Aqueous Hydrogenation of 3-buten-2-ol on Pd-black

    SciTech Connect

    Disselkamp, Robert S.; Chin, Ya-Huei; Peden, Charles HF.

    2004-10-25

    The effect of ultrasound at 20 kHz on the heterogeneous aqueous hydrogenation of 3-buten-2-ol employing a Pd-black catalyst has been studied isothermally at 295 K, forming 2-butanone and 2-butanol products. Our work here shows that adding 1-pentanol as an inert dopant had the effect of inducing cavitation in the ultrasound-treated reaction where it otherwise would not occur. The selectivity showed a 700% increase toward 2-butanol formation and the activity enhanced a factor of 10.8 compared to the noncavitating high-power ultrasound experiment. This study demonstrates that ''inert dopants'' may have use as synthetic tools in sonocatalysis.

  10. Regioselective alkane hydroxylation with a mutant CYP153A6 enzyme

    DOEpatents

    Koch, Daniel J.; Arnold, Frances H.

    2013-01-29

    Cytochrome P450 CYP153A6 from Myobacterium sp. strain HXN1500 was engineered using in-vivo directed evolution to hydroxylate small-chain alkanes regioselectively. Mutant CYP153A6-BMO1 selectively hydroxylates butane and pentane at the terminal carbon to form 1-butanol and 1-pentanol, respectively, at rates greater than wild-type CYP153A6 enzymes. This biocatalyst is highly active for small-chain alkane substrates and the regioselectivity is retained in whole-cell biotransformations.

  11. Effect of release rate and enantiomeric composition on response to pheromones of Megaplatypus mutatus (Chapuis) in poplar plantations of Argentina and Italy.

    PubMed

    Funes, Hernán; Zerba, Eduardo; Gonzalez-Audino, Paola

    2013-10-01

    Megaplatypus mutatus (=Platypus sulcatus Chapuis) is an Ambrosia beetle native to South America, which was recently introduced in Italy and its presence there is causing severe damage to the local poplar plantations. The male M. mutatus pheromone is composed of (S)-(+)-6-methyl-5-hepten-2-ol [(+)-sulcatol], 6-methyl-5-hepten-2-one (sulcatone) and 3-pentanol. A series of field trials testing dose, blend and enantiomer composition performed in Argentina and Italy evaluated attraction and found that the optimal release rate of pheromone components as baits in cross vane baited traps (CIPEIN-CV) was 6, 6 and 30 mg day?1 of sulcatone, (+)-sulcatol and 3-pentanol, respectively. It was also determined that racemic sulcatol is as effective as the pure (+)-isomer for the purpose of beetle catch, due to the inert nature of the (?)-isomer allowing the usage of low cost racemic sulcatol instead of highly expensive (+)-sulcatol. The results of our work contribute to the development of pheromone-based local technologies with low environmental impact and low cost for control or monitoring of an important pest. PMID:23590828

  12. Metabolites of lesser grain borer in grains.

    PubMed

    Seitz, Larry M; Ram, M S

    2004-02-25

    Many volatile alcohol and ester metabolites of the lesser grain borer (LGB, Rhyzopertha dominica) cultured on wheat grain were identified. Volatiles from infested samples at 80 degrees C were collected on Tenax absorbent, thermally desorbed, and analyzed by gas chromatography (GC) using infrared (IR) and mass (MS) detectors for component identification. A solid-phase microextraction (SPME) technique was used to analyze selected samples with a GC-MS system set up for obtaining chemical ionization mass spectra. SPME was also used in a synthesis process required to identify ester metabolites. Predominant compounds in LGB-infested grains were 2-pentanol and its esters of 2-methyl-2-pentenoic (A) and 2,4-dimethyl-2-pentenoic (B) acids, which are known aggregation pheromones, dominicalures 1 and 2. 2-Pentanol esters of saturated A, beta-keto- and beta-hydroxy derivatives of A and B, homologues of A and B, and acid moieties lacking the 2-methyl substitution were found. Other straight- and branched-chain secondary alcohols and their esters were also observed. Reexamination of GC-MS-IR data acquired in previous investigations of LGB cultured on sorghum grain and commercial samples in a grain odor study showed the presence of many LGB metabolites in addition to the known dominicalures. PMID:14969548

  13. Determination of volatile metabolites originating from mould growth on wall paper and synthetic media.

    PubMed

    Matysik, Silke; Herbarth, Olf; Mueller, Andrea

    2008-10-01

    Microbial volatile organic compounds (MVOCs) emitted from the mould species Penicillium expansum, P. chrysogenum, Aspergillus versicolor, A. fumigatus, A. niger and Cladosporium cladosporoides were analyzed by means of solid phase microextraction (SPME) and GCMS. The mould species were cultivated on the synthetic agar dichloran chloramphenicol (DG 18) and on wet wall paper. The production of MVOCs was monitored over several weeks to detect changes in the emission rates between the initial stage and later periods of growth. The cultivation on the synthetic agar resulted in MVOC patterns with a wide variety of signals. In contrast, the growth on wet wall paper led to changed MVOC patterns with less signals. The emission rates were drastically reduced. Components emitted by all six fungi species on wall paper were 2-pentanol and 2-pentanone. 1-Octen-3-ol was emitted by five fungi species. 2-Pentanol was only detected in considerable amounts during the first days of growth whereas 1-octen-3-ol had a more constant emission rate over the whole period of growth. On the basis of our studies some MVOCs could be proposed as specific for single fungi on wall paper, e.g. 1,3-dimethoxybenzene for A. versicolor and 2,4-pentandione for A. fumigatus. PMID:18577403

  14. The Yang-Yang anomaly in liquid-liquid criticality: Experimental evidence from adiabatic scanning calorimetry

    NASA Astrophysics Data System (ADS)

    Losada-Pérez, Patricia; Tripathi, Chandra Shekhar Pati; Leys, Jan; Cerdeiriña, Claudio A.; Glorieux, Christ; Thoen, Jan

    2012-01-01

    Using adiabatic scanning calorimetry, we have found the first experimental evidence of the Yang-Yang anomaly in liquid-liquid criticality from high-resolution two-phase isobaric heat capacity measurements for the binary mixture 3-pentanol + nitromethane. The results suggest a rather strong effect. The critical amplitude of the partial molar heat capacity is higher for the component with larger molecular volume, in accordance with the predictions of complete scaling as obtained from the customary observed asymmetric behavior of the coexistence-curve diameter. This consolidates complete scaling as the true formulation of fluid-fluid criticality. The quantitative analysis indicates that molecular size is not the only microscopic factor at play in asymmetric liquid-liquid criticality.

  15. Interplay of metalloligand and organic ligand to tune micropores within isostructural mixed-metal organic frameworks (M'MOFs) for their highly selective separation of chiral and achiral small molecules.

    PubMed

    Das, Madhab C; Guo, Qunsheng; He, Yabing; Kim, Jaheon; Zhao, Cong-Gui; Hong, Kunlun; Xiang, Shengchang; Zhang, Zhangjing; Thomas, K Mark; Krishna, Rajamani; Chen, Banglin

    2012-05-23

    Four porous isostructural mixed-metal-organic frameworks (M'MOFs) have been synthesized and structurally characterized. The pores within these M'MOFs are systematically tuned by the interplay of both the metalloligands and organic ligands which have enabled us not only to direct their highly selective separation of chiral alcohols 1-phenylethanol (PEA), 2-butanol (BUT), and 2-pentanol (2-PEN) with the highest ee up to 82.4% but also to lead highly selective separation of achiral C(2)H(2)/C(2)H(4) separation. The potential application of these M'MOFs for the fixed bed pressure swing adsorption (PSA) separation of C(2)H(2)/C(2)H(4) has been further examined and compared by the transient breakthrough simulations in which the purity requirement of 40 ppm in the outlet gas can be readily fulfilled by the fixed bed M'MOF-4a adsorber at ambient conditions. PMID:22545712

  16. Liquid chromatographic analysis of coal surface properties

    SciTech Connect

    Kwon, K.C.

    1992-12-15

    Experiments on equilibrium adsorption of various alcohols on 60--200 mesh Illinois No. 6 coal (DECS-2; Randolph county) were performed during the July--September period. The alcohols include ethanol, methanol, isobutanol, t-butanol, 1-heptanol, 1-octanol, 1-hexadecanol, 4-methyl-2-pentanol, and 2-methyl-l-pentanol. Amounts of equilibrium adsorption of alcohols (ALCO) on 60--200 mesh Illinois No. 6 coal are 1 - 230 [times] 10[sup [minus]6] mg-ALCO/g-coal, whereas equilibrium concentrations of alcohols are 3--40 ppM. Relations between equilibrium loadings of alcohols on the coal and equilibrium concentrations of alcohols in aqueous solutions are shown to be linear.

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

    NASA Astrophysics Data System (ADS)

    Golub, P.; 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.

  18. Optical constants of alcohols in the infrared

    NASA Technical Reports Server (NTRS)

    Sethna, P. P.; Williams, D.

    1979-01-01

    The spectral reflectances at near-normal incidence for methanol, ethanol, 1-propanol, 1-butanol, and 1-pentanol are reported for the spectral range 6700-350 kaysers. The real and imaginary parts of the complex index of refraction of these liquids are obtained in the range 4000-400 kaysers by use of Kramers-Kronig phase-shift analysis. For all of the alcohols studied, the strength for the OH-stretch bands is directly proportional to the number of OH groups per unit volume; similar relations are established for CH- and CO-stretch bands. Absorption cross sections for stretch vibrations of the three groups are considered, and the role of characteristic group intensities in intensity spectroscopy is discussed.

  19. Molecular interaction studies of acrylic esters with 1-alcohols

    NASA Astrophysics Data System (ADS)

    Sivagurunathan, P.; Dharmalingam, K.; Ramachandran, K.

    2006-05-01

    Hydrogen bonding between 1-alcohols and acrylic esters in n-heptane has been studied by FTIR spectroscopic method. The formation constant of the 1:1 complexes has been calculated using Nash method. The values of formation constant and free energy change vary with alcohol and ester chain length, which suggests that the strengths of the intermolecular O-H⋯O dbnd C bonds are shown to be dependent on the alkyl group of acrylic esters and the 1-alcohols and the results shows that the proton donating ability of 1-alcohols is in the order: 1-propanol < 1-butanol < 1-pentanol and the accepting ability of acrylic esters is in the order: methyl methacrylate < ethyl methacrylate < butyl methacrylate.

  20. Seed-germination inhibition by volatile alcohols and other compounds associated withAmaranthus palmeri residues.

    PubMed

    Bradow, J M; Connick, W J

    1988-07-01

    Effects of 3-pentanone and eight low molecular weight aliphatic alcohols and aldehydes identifed in the mixtures of volatiles released byAmaranthus palmeri S. Wats. (AMAPA) residues were determined on germination of onion, carrot, AMAPA, and tomato seeds. Three-day exposures to these volatiles significantly inhibited germination of these assay seeds, and the inhibition was dependent upon exposure time and concentration. Based on the degree of inhibition observed in both time- and concentration-dependent assays, the following activity series was obtained: 2-heptanol > 3-methyl-1-butanol, 1-hexanol > hexanal, 1-pentanol, 3-pentanone, acetaldehyde > ethanol, 2-methyl-1-propanol. The activities of this group of compounds with that of 2-heptanone appear to be additive and related to test compound volatility and hydrophilicity. 2-Heptanol and 2-heptanone also significantly inhibited the germination of other species, including shepherdspurse, soybean, lettuce, alfalfa, common purslane, oats, and lovegrass. PMID:24276435

  1. Headspace analysis of engine oil by gas chromatography/mass spectrometry.

    PubMed

    Levermore, D M; Josowicz, M; Rees, W S; Janata, J

    2001-03-15

    This study establishes the rationale necessary for determining the time to change engine oil. This is based on identifying gaseous components in new and used automobile lubricants. Key compounds, so-called "signature", are separated and identified qualitatively by coupled gas chromatography/mass spectrometry. Volatile antioxidants at zero miles and fuel contaminants at low mileage are observed in the headspace of engine oil. Several oxidative degradation components have been positively identified in the used oil, which include the following: acetaldehyde, acetone, butanal, 2-propanol, acetic acid, 2-hexanol, benzoic acid, benzaldehyde, and 1-pentanol. This study strongly suggests that the status of lubricating oil can be determined by the analysis of the gas phase above the oil. Most importantly, it opens the possibility of performing conditional maintenance of the combustion engine based on information obtained from gas sensors. PMID:11305675

  2. Characterization of a new mobility separation tool: HRIMS as differential mobility analyzer.

    PubMed

    Bouza, Marcos; López-Vidal, Silvia; Pisonero, Jorge; Bordel, Nerea; Pereiro, Rosario; Sanz-Medel, Alfredo

    2014-12-01

    High resolution ion mobility spectrometer (HRIMS) is a new instrument that uses parallel plate Differential Mobility Analysis as principle of separation. Gas phase analysis of volatile organic compounds (VOCs) has been performed for the characterization of this new mobility system using an UV-lamp for ionization. Studies of the effect of temperature and the presence of a desiccant are detailed. Identification of the different peaks obtained with an electrometer was successfully carried out for a group of alcohols, aromatic compounds and ketones (ethanol, 1-propanol, isopropanol, 1-butanol, 1-pentanol, 1-heptanol, acetone, 2-butanone, 2-pentanone, 2-octanone, benzene, toluene, xylene and bromobenzene) following a modified Millikan equation. Moreover, the investigation of the discrimination capabilities within the different VOCs families as well as the mobility dependence with molecular mass was successfully achieved. PMID:25159427

  3. Kinetics and products of the reactions of hydroxyl radicals with selected volatile organic compounds, including oxygenated compounds

    NASA Astrophysics Data System (ADS)

    Bethel, Heidi Lynn

    Kinetics, products and reaction mechanisms of the OH radical-initiated reactions of selected volatile organic compounds (VOCs) and oxygenated compounds were examined. These compounds are important smog forming chemicals that are found in gasoline and many consumer products. Smog is created by the interaction of these VOCs with oxides of nitrogen in the presence of sunlight. The hydroxyl (OH) radical is a daytime species and a key initiator of the VOC reactions which lead to photochemical smog formation. Chapter II investigates the OH radical-initiated reactions of p-xylene, 1,2,3-, and 1,2,4-trimethylbenzene which are components of gasoline fuels, vehicle exhaust and ambient air in urban areas. Experiments were conducted at varying NO2 concentrations in indoor environmental chambers in order to determine the dependence of the product yields as a function of NO2 concentrations. From these experiments and previous literature yields, a majority of the products from these reactions under atmospheric conditions have now been elucidated. Chapter III examines the OH radical-initiated reaction of 3-hexene-2,5-dione which is formed from the reactions of p-xylene and 1,2,4-trimethylbenzene (Chapter II). Due to its polar nature, 3-hexene-2,5-dione and its reaction products are difficult to handle experimentally. Products identified from this reaction through the use of in situ atmospheric pressure ionization tandem mass spectrometry were CH3C(O)CH(OH)CHO and CH 3C(O)CH(OH)CH(ONO2)C(O)CH3. Chapters IV, V, and VI examine the OH radical-initiated reactions of 6 different alcohols, including diols. The products examined in Chapters IV and V are those from 2-methyl-2,4-pentanediol and 1,2-, 1,3-, and 2,3-butanediol, which are found in various solvents. Reaction rates were determined using a relative rate method. Hydroxyaldehyde and hydroxyketone products from these reactions were also quantified. Chapter VI examined the reaction rates and products formed from the OH radical-initiated reactions of 2-methyl-2-pentanol and 4-methyl-2-pentanol. These compounds were studied in order to investigate the formation of alkoxy radicals (RO•) and their subsequent reactions through isomerization, decomposition or reaction with O2 . Experiments of the type detailed here allow the determination of kinetics and products of the atmospheric reactions of VOCs and provide input for mechanistic models of photochemical smog formation.

  4. Dislodgement effect of natural semiochemicals released by disturbed triatomines: a possible alternative monitoring tool.

    PubMed

    Minoli, Sebastián; Palottini, Florencia; Crespo, Jose Guillermo; Manrique, Gabriel

    2013-12-01

    The quick detection of domestic and peridomestic triatomines in their environments becomes difficult without the use of dislodgement substances that flush them out from their shelters. At present, tetramethrin 0.2% is being widely used in control programs. Although it is an efficient dislodging agent, its toxicity might affect the health of captured triatomines, of other insects and, to a lesser extent, of other animals, including humans. Here, we tested if semiochemicals released by disturbed adults of Triatoma infestans and/or Rhodnius prolixus can make larvae of the same species exit from their refuges. In a walking olfactometer we found that: 1) larvae of T. infestans were repelled by the odors released by disturbed adults of their own species and of R. prolixus, 2) larvae of R. prolixus did not change their behavior in the presence of odors released by adults of both species, and 3) activity levels were not modulated by these odors in any of both species. Besides, in pseudo-natural conditions we found an increased flushing-out activity of larvae of T. infestans when their shelters were sprayed with isobutyric acid or 3-pentanol, and of larvae of R. prolixus when sprayed with 3-methyl-1-butanol. We succeeded in this work to dislodge larvae of triatomines from artificial shelters using natural volatile compounds, allowing the capture of live bugs for further investigations (e.g., xenodiagnosis or genetic studies) and favoring ecological aspects (e.g., minimizing environmental insecticide-contamination and non-targeted mortality). PMID:24581366

  5. Authentication of fattening diet of Iberian pigs according to their volatile compounds profile from raw subcutaneous fat.

    PubMed

    Narváez-Rivas, M; Pablos, F; Jurado, J M; León-Camacho, M

    2011-02-01

    The composition of volatile components of subcutaneous fat from Iberian pig has been studied. Purge and trap gas chromatography-mass spectrometry has been used. The composition of the volatile fraction of subcutaneous fat has been used for authentication purposes of different types of Iberian pig fat. Three types of this product have been considered, montanera, extensive cebo and intensive cebo. With classification purposes, several pattern recognition techniques have been applied. In order to find out possible tendencies in the sample distribution as well as the discriminant power of the variables, principal component analysis was applied as visualisation technique. Linear discriminant analysis (LDA) and soft independent modelling by class analogy (SIMCA) were used to obtain suitable classification models. LDA and SIMCA allowed the differentiation of three fattening diets by using the contents in 2,2,4,6,6-pentamethyl-heptane, m-xylene, 2,4-dimethyl-heptane, 6-methyl-tridecane, 1-methoxy-2-propanol, isopropyl alcohol, o-xylene, 3-ethyl-2,2-dimethyl-oxirane, 2,6-dimethyl-undecane, 3-methyl-3-pentanol and limonene. PMID:21072505

  6. Optimal Estimation of Residual Non-Aqueous Phase Liquid Residual Saturations Using Inter-Well Tracer Test Data at OU1 Test Cell, Hill AFB

    NASA Astrophysics Data System (ADS)

    Zhang, Y.; Graham, W. D.; Annable, M. D.; Hatfield, K.; Rao, P.

    2001-05-01

    Inter-well tracer tests (IWTT) were conducted at the OU1 test cell at Hill AFB to characterize its hydrogeochemical properties. The test cell was constructed in an aquifer historically contaminated by light nonaqueous phase liquids (LNAPL) such as aviation fuels (JP4) and smaller amounts of chlorinated solvents. Concentrations of a nonpartitioning tracer (bromide) and a number of partitioning tracers (notably, 2,2-Dimethyl-3-Pentanol) were measured at 12 multilevel samplers within the test cell. Assuming the unknown hydraulic conductivity distribution and NAPL distribution can be represented by two random fields, a distributed parameter extended Kalman Filter was developed based upon the three-dimensional advection-dispersion-retardation equations. The nonpartitioning tracer concentration data was used in the Kalman filter to optimally estimate Darcy flux distribution, while the partitioning tracer concentration data was used to optimally estimate residual NAPL distribution. Both the estimated parameter distributions and estimation accuracy were quantified. The estimated NAPL distribution from the inverse stochastic model compared favorably to those derived from soil core and temporal moment analysis.

  7. Aroma enhancement and enzymolysis regulation of grape wine using ?-glycosidase.

    PubMed

    Zhu, Feng-Mei; Du, Bin; Li, Jun

    2014-03-01

    Adding ?-glycosidase into grape wine for enhancing aroma was investigated using gas chromatography-mass spectrometry (GC-MS) and Kramer sensory evaluation. Compared with the extract from control wines, the extract from enzyme-treated wines increased more aromatic compounds using steam distillation extraction (SDE) and GC-MS analyses. Theses aromatic compounds were as follows: 3-methyl-1-butanol formate, 3-pentanol, furfural, 3-methyl-butanoic acid, 2-methyl-butanoic acid, 3-hydroxy-butanoic acid ethyl ester, hexanoic acid, hexanoic acid ethyl ester, benzyl alcohol, octanoic acid, octanoic acid ethyl ester, dodecanoic acid, and ethyl ester. The enzymolysis regulation conditions, including enzymolysis temperature, enzymolysis time, and enzyme amount, were optimized through L9(3(4)) orthogonal test. Kramer sensory evaluation was performed by an 11-man panel of judges. The optimum enzymolysis regulation conditions were found to be temperature of 45°C, enzymolysis time of 90 min, and enzyme amount of 58.32 U/mL grape wine, respectively. The Kramer sensory evaluation supported that the enzyme-treated wines produced a stronger fragrance. PMID:24804072

  8. Electrophysiological and behavioral responses of male fall webworm moths (Hyphantria cunea) to Herbivory-induced mulberry (Morus alba) leaf volatiles.

    PubMed

    Tang, Rui; Zhang, Jin Ping; Zhang, Zhong Ning

    2012-01-01

    Volatile organic compounds (VOCs) were collected from damaged and intact mulberry leaves (Morus alba L., Moraceae) and from Hyphantria cunea larvae by headspace absorption with Super Q columns. We identified their constituents using gas chromatography-mass spectrometry, and evaluated the responses of male H. cunea antennae to the compounds using gas chromatography-flame ionization detection coupled with electroantennographic detection. Eleven VOC constituents were found to stimulate antennae of male H. cunea moths: ?-ocimene, hexanal, cis-3-hexenal, limonene, trans-2-hexenal, cyclohexanone, cis-2-penten-1-ol, 6-methyl-5-hepten-2-one, 4-hydroxy-4-methyl-2-pentanone, trans-3-hexen-1-ol, and 2,4-dimethyl-3-pentanol. Nine of these chemicals were released by intact, mechanically-damaged, and herbivore-damaged leaves, while cis-2-penten-1-ol was released only by intact and mechanically-damaged leaves and ?-ocimene was released only by herbivore-damaged leaves. Results from wind tunnel experiments conducted with volatile components indicated that male moths were significantly more attracted to herbivory-induced volatiles than the solvent control. Furthermore, male moths' attraction to a sex pheromone lure was increased by herbivory-induced compounds and ?-ocimene, but reduced by cis-2-penten-1-ol. A proof long-range field trapping experiment showed that the efficiency of sex pheromone lures in trapping male moths was increased by ?-ocimene and reduced by cis-2-penten-1-ol. PMID:23166622

  9. Electrophysiological and Behavioral Responses of Male Fall Webworm Moths (Hyphantria cunea) to Herbivory-Induced Mulberry (Morus alba) Leaf Volatiles

    PubMed Central

    Tang, Rui; Zhang, Jin Ping; Zhang, Zhong Ning

    2012-01-01

    Volatile organic compounds (VOCs) were collected from damaged and intact mulberry leaves (Morus alba L., Moraceae) and from Hyphantria cunea larvae by headspace absorption with Super Q columns. We identified their constituents using gas chromatography-mass spectrometry, and evaluated the responses of male H. cunea antennae to the compounds using gas chromatography-flame ionization detection coupled with electroantennographic detection. Eleven VOC constituents were found to stimulate antennae of male H. cunea moths: ?-ocimene, hexanal, cis-3-hexenal, limonene, trans-2-hexenal, cyclohexanone, cis-2-penten-1-ol, 6-methyl-5-hepten-2-one, 4-hydroxy-4-methyl-2-pentanone, trans-3-hexen-1-ol, and 2,4-dimethyl-3-pentanol. Nine of these chemicals were released by intact, mechanically-damaged, and herbivore-damaged leaves, while cis-2-penten-1-ol was released only by intact and mechanically-damaged leaves and ?-ocimene was released only by herbivore-damaged leaves. Results from wind tunnel experiments conducted with volatile components indicated that male moths were significantly more attracted to herbivory-induced volatiles than the solvent control. Furthermore, male moths' attraction to a sex pheromone lure was increased by herbivory-induced compounds and ?-ocimene, but reduced by cis-2-penten-1-ol. A proof long-range field trapping experiment showed that the efficiency of sex pheromone lures in trapping male moths was increased by ?-ocimene and reduced by cis-2-penten-1-ol. PMID:23166622

  10. Aroma enhancement and enzymolysis regulation of grape wine using ?-glycosidase

    PubMed Central

    Zhu, Feng-Mei; Du, Bin; Li, Jun

    2014-01-01

    Adding ?-glycosidase into grape wine for enhancing aroma was investigated using gas chromatography-mass spectrometry (GC-MS) and Kramer sensory evaluation. Compared with the extract from control wines, the extract from enzyme-treated wines increased more aromatic compounds using steam distillation extraction (SDE) and GC-MS analyses. Theses aromatic compounds were as follows: 3-methyl-1-butanol formate, 3-pentanol, furfural, 3-methyl-butanoic acid, 2-methyl-butanoic acid, 3-hydroxy-butanoic acid ethyl ester, hexanoic acid, hexanoic acid ethyl ester, benzyl alcohol, octanoic acid, octanoic acid ethyl ester, dodecanoic acid, and ethyl ester. The enzymolysis regulation conditions, including enzymolysis temperature, enzymolysis time, and enzyme amount, were optimized through L9(34) orthogonal test. Kramer sensory evaluation was performed by an 11-man panel of judges. The optimum enzymolysis regulation conditions were found to be temperature of 45°C, enzymolysis time of 90 min, and enzyme amount of 58.32 U/mL grape wine, respectively. The Kramer sensory evaluation supported that the enzyme-treated wines produced a stronger fragrance. PMID:24804072

  11. Two Volatile Organic Compounds Trigger Plant Self-Defense against a Bacterial Pathogen and a Sucking Insect in Cucumber under Open Field Conditions.

    PubMed

    Song, Geun Cheol; Ryu, Choong-Min

    2013-01-01

    Systemic acquired resistance (SAR) is a plant self-defense mechanism against a broad-range of pathogens and insect pests. Among chemical SAR triggers, plant and bacterial volatiles are promising candidates for use in pest management, as these volatiles are highly effective, inexpensive, and can be employed at relatively low concentrations compared with agrochemicals. However, such volatiles have some drawbacks, including the high evaporation rate of these compounds after application in the open field, their negative effects on plant growth, and their inconsistent levels of effectiveness. Here, we demonstrate the effectiveness of volatile organic compound (VOC)-mediated induced resistance against both the bacterial angular leaf spot pathogen, Pseudononas syringae pv. lachrymans, and the sucking insect aphid, Myzus persicae, in the open field. Using the VOCs 3-pentanol and 2-butanone where fruit yields increased gave unexpectedly, a significant increase in the number of ladybird beetles, Coccinella septempunctata, a natural enemy of aphids. The defense-related gene CsLOX was induced by VOC treatment, indicating that triggering the oxylipin pathway in response to the emission of green leaf volatiles can recruit the natural enemy of aphids. These results demonstrate that VOCs may help prevent plant disease and insect damage by eliciting induced resistance, even in open fields. PMID:23698768

  12. INVITED PAPER: Surfactant effect on the bubble motions and bubbly flow structures in a vertical channel

    NASA Astrophysics Data System (ADS)

    Takagi, Shu; Ogasawara, Toshiyuki; Fukuta, Masato; Matsumoto, Yoichiro

    2009-12-01

    It is well known that a small amount of surfactant can drastically change the motion of a single bubble and this causes a dramatic change of the whole bubbly flow structure. In our previous studies using upward vertical channel flows, it was shown that surfactant influences the shear-induced lift and the lateral migration of a bubble, which causes bubble accumulation and clustering near the wall. In this paper, the dependence of surfactant concentration on the motions of a 1 mm bubble rising through the laminar shear flow is investigated using 1-, 3-Pentanol and Triton X-100. The results are compared with the numerical ones, which show quantitative agreement on the lift and drag forces. Furthermore, we analyze the experimental data for the condition of bubble clustering in upward channel flows with the consideration of contaminant level in tap water. The results indicate that lower contaminant level and higher shear rate cause the significant bubble migration toward the wall, which leads to the formation of bubble clusters.

  13. Studies on the interaction between ethanol and two industrial solvents (methyl isobutyl ketone) in mice

    SciTech Connect

    Granvil, C.P.; Sharkawi, M.; Plaa, G.L. (Univ. de Montreal, Quebec (Canada))

    1991-03-11

    Methyl n-butyl ketone (MnBK) and methyl isobutyl ketone (MiBK) prolong the duration of ethanol-induced loss of righting reflex (EILRR) in mice. MnBK was almost twice as potent in this regard. To explain this difference, the metabolism of both ketones was studied in male CD-1 mice using GC. MiBK was converted to 4-methyl-2-pentanol (4MPOL) and 4-hydroxy methyl isobutyl ketone (HMP). MnBK metabolites were 2-hexanol (2HOL) and 2,5-hexanedione (2,5HD). The effects of both ketones and metabolites on EILRR and ethanol (E) elimination were studied in mice. The ketones and their metabolites were dissolved in corn oil and injected intraperitoneally 30 min before E 4g/kg for EILRR and 2g/kg for E elimination. In the following doses: MnBK, 5; MiBK, 5; 2HOL, 2.5; 4MPOL, 2.5; and HMP 2.5, significantly prolonged EILRR. Concentrations of E in blood and brain upon return of the righting reflex were similar in solvent-treated and control animals. The mean elimination rate of E was slower in groups given MnBK or 2HOL than in control animals. No change in E elimination was observed with MiBK, HMP, 4MPOL, or 2, 5HD.

  14. Interplay of Metalloligand and Organic Ligand to Tune Micropores within Isostructural Mixed-Metal Organic Frameworks (M MOFs) for Their Highly Selective Separation of Chiral and Achiral Small Molecules

    SciTech Connect

    Madhab, Das [University of Texas at San Antonio (UTSA); He, Yabing [University of Texas at San Antonio (UTSA); Kim, Jaheon [Soongsil University, Korea; Guo, Qunsheng [University of Texas at San Antonio (UTSA); Zhao, Cong-Gui [University of Texas at San Antonio (UTSA); Hong, Kunlun [ORNL; Xiang, Sheng-Chang [University of Texas at San Antonio (UTSA); Zhang, Zhangjing [University of Texas at San Antonio (UTSA); Thomas, K Mark [University of Newcastle upon Tyne; Krishna, Rajamani [Universitate Amsterdam; Chen, Banglin [University of Texas at San Antonio (UTSA)

    2012-01-01

    Four porous isostructural mixed-metal-organic frameworks (M'MOFs) have been synthesized and structurally characterized. The pores within these M'MOFs are systematically tuned by the interplay of both the metalloligands and organic ligands which have enabled us not only to direct their highly selective separation of chiral alcohols 1-phenylethanol (PEA), 2-butanol (BUT), and 2-pentanol (2-PEN) with the highest ee up to 82.4% but also to lead highly selective separation of achiral C{sub 2}H{sub 2}/C{sub 2}H{sub 4} separation. The potential application of these M'MOFs for the fixed bed pressure swing adsorption (PSA) separation of C{sub 2}H{sub 2}/C{sub 2}H{sub 4} has been further examined and compared by the transient breakthrough simulations in which the purity requirement of 40 ppm in the outlet gas can be readily fulfilled by the fixed bed M'MOF-4a adsorber at ambient conditions.

  15. Volatile Compounds Originating from Mixed Microbial Cultures on Building Materials under Various Humidity Conditions

    PubMed Central

    Korpi, Anne; Pasanen, Anna-Liisa; Pasanen, Pertti

    1998-01-01

    We examined growth of mixed microbial cultures (13 fungal species and one actinomycete species) and production of volatile compounds (VOCs) in typical building materials in outside walls, separating walls, and bathroom floors at various relative humidities (RHs) of air. Air samples from incubation chambers were adsorbed on Tenax TA and dinitrophenylhydrazine cartridges and were analyzed by thermal desorption-gas chromatography and high-performance liquid chromatography, respectively. Metabolic activity was measured by determining CO2 production, and microbial concentrations were determined by a dilution plate method. At 80 to 82% RH, CO2 production did not indicate that microbial activity occurred, and only 10% of the spores germinated, while slight increases in the concentrations of some VOCs were detected. All of the parameters showed that microbial activity occurred at 90 to 99% RH. The microbiological analyses revealed weak microbial growth even under drying conditions (32 to 33% RH). The main VOCs produced on the building materials studied were 3-methyl-1-butanol, 1-pentanol, 1-hexanol, and 1-octen-3-ol. In some cases fungal growth decreased aldehyde emissions. We found that various VOCs accompany microbial activity but that no single VOC is a reliable indicator of biocontamination in building materials. PMID:9687450

  16. Anticancer Properties of Novel Rhenium Pentylcarbanato Compounds against MDA-MB-468(HTB-132) Triple Node Negative Human Breast Cancer Cell Lines

    PubMed Central

    Parson, Carl; Smith, Valerie; Krauss, Christopher; Banerjee, Hirendra N.; Reilly, Christopher; Krause, Jeanette A.; Wachira, James M.; Giri, Dipak; Winstead, Angela; Mandal, Santosh K.

    2014-01-01

    Aim To study the efficacy of novel rhenium compounds to treat triple node negative breast cancer. Place and Duration Six (6) novel rhenium pentycarbanato compounds (PC1-6) were synthesized and triple node negative breast cancer cell lines HTB-132 and Balb/c mouse kidney cell lines were treated with each of them for 48 hours. The results were analyzed by a common trypan blue cell death assay system and statistically analyzed. Place and Duration The compounds were synthesized, analyzed and evaluated at the Department of Chemistryof Morgan State University, Baltimore, Maryland and the Pharmaceutical Sciences Department of Elizabeth City State University campus of the University of North Carolina system. Methodology The novel rhenium compounds were synthesized from one-pot reactions of Re2(CO)10 with the corresponding ?-diimine ligands in 1-pentanol.The compounds were characterized spectroscopically. The cell lines were cultured by standard cell culture procedure and treated with each of the six compounds in DMSO for 48 hours with a negative control and a DMSO vehicular control along with a cisplatin positive control.The cytotoxicity was evaluated by standard trypan blue assay and the results were statistically analyzed. Results The trypan blueassay reveals that these compounds have significant cytotoxicity against MDA-MB-468 (HTB-132) triple node negative breast cancer cell lines and are less nephrotoxic than cisplatin. Conclusion The novel rhenium compounds PC 1-6 can potentially find applications in the treatment of highly malignant triple node negative breast cancer. PMID:25419517

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

    PubMed

    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)n H+ 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)n H+. The mixture of these alcohols, including two isomers, has been detected, and the results showed that they could 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. PMID:17969651

  18. All-catalytic, efficient, and asymmetric synthesis of alpha,omega-diheterofunctional reduced polypropionates via "one-pot" Zr-catalyzed asymmetric carboalumination-Pd-catalyzed cross-coupling tandem process.

    PubMed

    Novak, Tibor; Tan, Ze; Liang, Bo; Negishi, Ei-Ichi

    2005-03-01

    A highly efficient method for the synthesis of stereochemically pure (>/=99% ee and >50/1 dr) alpha,omega-diheterofunctional reduced polypropionates has been developed. The essential features of the method are represented by the conversion of inexpensive styrene into 2-methyl-4-phenyl-1-pentanol (1) in 50% yield over two steps from styrene via Zr-catalyzed asymmetric carboalumination (ZACA) reaction in the presence of (NMI)2ZrCl2 and Pd-catalyzed vinylation of the in situ generated isoalkylalanes in the presence of Zn(OTf)2 and a catalytic amount of Pd(DPEphos)Cl2. This ZACA-Pd-catalyzed vinylation may be repeated as needed without purification. After the final ZACA reaction, oxidation with O2 provides alpha-hydroxy-omega-phenyl reduced polypropionates, which can be fully or partially purified by chromatography. After acetylation, Ru-catalyzed oxidative cleavage of the Ph ring, and reduction with BH3.THF, the second chromatographic purification provides stereoisomerically pure alpha,omega-diheterofunctional reduced polypropionates (e.g., 9 and 11) that can be further converted to key intermediates 6 and 7 for the synthesis of ionomycin (4) and borrelidin (5), respectively, by known reactions. PMID:15740104

  19. Dielectric barrier discharge carbon atomic emission spectrometer: universal GC detector for volatile carbon-containing compounds.

    PubMed

    Han, Bingjun; Jiang, Xiaoming; Hou, Xiandeng; Zheng, Chengbin

    2014-01-01

    It was found that carbon atomic emission can be excited in low temperature dielectric barrier discharge (DBD), and an atmospheric pressure, low power consumption, and compact microplasma carbon atomic emission spectrometer (AES) was constructed and used as a universal and sensitive gas chromatographic (GC) detector for detection of volatile carbon-containing compounds. A concentric DBD device was housed in a heating box to increase the plasma operation temperature to 300 °C to intensify carbon atomic emission at 193.0 nm. Carbon-containing compounds directly injected or eluted from GC can be decomposed, atomized, and excited in this heated DBD for carbon atomic emission. The performance of this new optical detector was first evaluated by determination of a series of volatile carbon-containing compounds including formaldehyde, ethyl acetate, methanol, ethanol, 1-propanol, 1-butanol, and 1-pentanol, and absolute limits of detection (LODs) were found at a range of 0.12-0.28 ng under the optimized conditions. Preliminary experimental results showed that it provided slightly higher LODs than those obtained by GC with a flame ionization detector (FID). Furthermore, it is a new universal GC detector for volatile carbon-containing compounds that even includes those compounds which are difficult to detect by FID, such as HCHO, CO, and CO2. Meanwhile, hydrogen gas used in conventional techniques was eliminated; and molecular optical emission detection can also be performed with this GC detector for multichannel analysis to improve resolution of overlapped chromatographic peaks of complex mixtures. PMID:24328147

  20. First total synthesis of the (±)-2-methoxy-6-heptadecynoic acid and related 2-methoxylated analogs as effective inhibitors of the leishmania topoisomerase IB enzyme

    PubMed Central

    Carballeira, Néstor M.; Cartagena, Michelle; Li, Fengyu; Chen, Zhongfang; Prada, Christopher F.; Calvo-Alvarez, Estefania; Reguera, Rosa M.; Balaña-Fouce, Rafael

    2012-01-01

    The fatty acids (±)-2-methoxy-6Z-heptadecenoic acid (1), (±)-2-methoxy-6-heptadecynoic acid (2) and (±)-2-methoxyheptadecanoic acid (3) were synthesized and their inhibitory activity against the Leishmania DNA topoisomerase IB enzyme (LdTopIB) determined. Acids 1 and 2 were synthesized from 4-bromo-1-pentanol, the former in ten steps and in 7% overall yield, while the latter in seven steps and in 14% overall yield. Acid 3 was prepared in six steps and in 42% yield from 1-hexadecanol. Acids 1–3 inhibited the LdTopIB enzyme following the order 2 > 1 ? 3, with 2 displaying an EC50 = 16.6 ± 1.1 ?M and 3 not inhibiting the enzyme. Acid 1 preferentially inhibited the LdTopIB enzyme over the human TopIB enzyme. Unsaturation seems to be a prerequisite for effective inhibition, rationalized in terms of weak intermolecular interactions between the active site of LdTopIB and either the double or triple bonds of the fatty acids. Toxicity towards Leishmania donovani promastigotes was also investigated resulting in the same order 2 > 1 > 3, with 2 displaying an EC50 = 74.0 ± 17.1 ?M. Our results indicate that ?-methoxylation decreases the toxicity of C17:1 fatty acids towards L. donovani promastigotes, but improves their selectivity index. PMID:23118491

  1. Aroma profiles of vegetable oils varying in fatty acid composition vs. concentrations of primary and secondary lipid oxidation products.

    PubMed

    van Ruth, S M; Roozen, J P; Jansen, F J

    2000-10-01

    The aroma compositions of oxidised sunflower oil, linseed oil and a blend thereof (85/15) were compared with frequently used indicators for primary and secondary lipid oxidation. Primary lipid oxidation was followed by the formation of conjugated dienes, secondary lipid oxidation by proponal and hexanal formation. Highest concentrations of conjugated dienes and propanal were measured in the linseed oil, followed by the blend and sunflower oil, respectively. Highest concentrations of hexanal were determined in the blend. At similar primary oxidation levels, volatile compounds of the oils were isolated in a model mouth system and subsequently analysed by gas chromatography/sniffing port analysis. Propanal, pentanal, 1-penten-3-one, hexanal, 1-pentanol, octanal, 1-octen-3-one, 1-octen-3-ol and (E,Z)-2,4-heptadienal possessed detectable odours. Comparing the three oils, most aroma compounds and greatest intensities were determined in the blend. Conjugated diene concentrations did not predict the formation of aroma compounds adequately. Although propanal and hexanal concentrations were reasonable indicators for aroma development in linseed and sunflower oil, respectively, neither of the indicators predicted aroma development in all three oils sufficiently. PMID:11075372

  2. Male and female noctuid moths attracted to synthetic lures in Europe.

    PubMed

    Tóth, Miklós; Szarukán, István; Dorogi, Béla; Gulyás, Attila; Nagy, Pál; Rozgonyi, Zoltán

    2010-06-01

    In field tests in Europe, traps baited with a blend of isoamyl alcohol, acetic acid, and isobutanol (compounds previously found attractive to a number of noctuids in North America) caught the following noctuid moths: Agrotis segetum Schiff., Agrotis crassa Hbn., Agrotis exclamationis L., Amathes (Xestia) c-nigrum L., Apatele rumicis L., Amphipyra pyramidea L., Dipterygia scabriuscula L., Discestra trifolii Hfn., Euxoa aquilina Schiff., Euclidia glyphica L., Mamestra brassicae L., Mamestra oleracea L., Mamestra suasa Schiff., Mythimna albipuncta Den. & Schiff., Mythimna l-album L., Noctua pronuba L., and Trachea atriplicis L. A substantial percentage of the catch of each species of moths was females. The presence of isobutanol in the mixture was important for catching A. rumicis, D. trifolii, and E. glyphica. The addition of 3-methyl-1-pentanol to the ternary mixture did not increase trap captures of any of the moths. Traps baited with the floral attractant phenylacetaldehyde alone caught several species of noctuid moths. However, when phenylacetaldehyde was added to the isoamyl-alcohol ternary blend, no increases in catches of any of the species, relative to the ternary blend or phenyacetaldehyde alone, were observed, with catches of most species being depressed. Comparing the noctuid species attracted to the phenylacetaldehyde- and isoamyl alcohol-based lures showed that phenylacetaldehyde attracted predominantly Plusiinae and Melicleptriinae spp., while isoamyl alcohol-based lures attracted species mostly from the Noctuinae or Hadeninae subfamilies. PMID:20449640

  3. Fractionation and identification of minor and aroma-active constituents in Kangra orthodox black tea.

    PubMed

    Joshi, Robin; Gulati, Ashu

    2015-01-15

    The aroma constituents of Kangra orthodox black tea were isolated by simultaneous distillation extraction (SDE), supercritical fluid extraction and beverage method. The aroma-active compounds were identified using gas chromatography-olfactometry-mass spectrometry. Geraniol, linalool, (Z/E)-linalool oxides, (E)-2-hexenal, phytol, ?-ionone, hotrienol, methylpyrazine and methyl salicylate were major volatile constituents in all the extracts. Minor volatile compounds in all the extracts were 2-ethyl-5-methylpyrazine, ethylpyrazine, 2-6,10,14-trimethyl-2-pentadecanone, acetylfuran, hexanoic acid, dihydroactinidiolide and (E/Z)-2,6-nonadienal. The concentrated SDE extract was fractionated into acidic, basic, water-soluble and neutral fractions. The neutral fraction was further chromatographed on a packed silica gel column eluted with pentane and diethyl ether to separate minor compounds. The aroma-active compounds identified using gas chromatography-olfactometry-mass spectrometry were 2-amylfuran, (E/Z)-2,6-nonadienal, 1-pentanol, epoxylinalool, (Z)-jasmone, 2-acetylpyrrole, farnesyl acetone, geranyl acetone, cadinol, cubenol and dihydroactinidiolide. AEDA studies showed 2-hexenal, 3-hexenol, ethylpyrazine, (Z/E)-linalool oxides, linalool, (E/Z)-2,6-nonadienal, geraniol, phenylethanol, ?-ionone, hotrienol and dihydroactinidiolide to be odour active components. PMID:25148991

  4. Heterologous expression of the alcohol dehydrogenase (adhI) gene from Geobacillus thermoglucosidasius strain M10EXG.

    PubMed

    Jeon, Young Jae; Fong, Jiunn C N; Riyanti, Eny I; Neilan, Brett A; Rogers, Peter L; Svenson, Charles J

    2008-06-01

    A thermostable alcohol dehydrogenase (ADH-I) isolated from the potential thermophilic ethanologen Geobacillus thermoglucosidasius strain M10EXG has been characterised. Inverse PCR showed that the gene (adhI) was localised with 3-hexulose-6-phosphate synthase (HPS) and 6-phospho-3 hexuloisomerase (PHI) on its genome. The deduced peptide sequence of the 1020-bp M10EXG adhI, which corresponds to 340 amino acids, shows 96% and 89% similarity to ADH-hT and ADH-T from Geobacillus stearothermophilus strains LLD-R and NCA 1503, respectively. Over-expression of M10EXG ADH-I in Escherichia coli DH5alpha (pNF303) was confirmed using an ADH activity assay and SDS-PAGE analysis. The specific ADH activity in the extract from this recombinant strain was 9.7(+/-0.3) U mg(-1) protein, compared to 0.1(+/-0.01) U mg(-1) protein in the control strain. The recombinant E. coli showed enzymatic activity towards ethanol, 1-butanol, 1-pentanol, 1-heptanol, 1-hexanol, 1-octanol and 2-propanol, but not methanol. In silico analysis, including phylogenetic reconstruction and protein modeling, confirmed that the thermostable enzyme from G. thermoglucosidasius is likely to belong to the NAD-Zn-dependent family of alcohol dehydrogenases. PMID:18436321

  5. Analysis of volatile compounds and triglycerides of seed oils extracted from different poppy varieties (Papaver somniferum L.).

    PubMed

    Krist, Sabine; Stuebiger, Gerald; Unterweger, Heidrun; Bandion, Franz; Buchbauer, Gerhard

    2005-10-19

    Poppy seed oil (Oleum Papaveris Seminis) is used for culinary and pharmaceutical purposes, as well as for making soaps, paints, and varnishes. Astonishingly, hardly anything was yet known about the volatile compounds of this promising comestible. Likewise, there are no current published data about the triglyceride (TAG) composition of poppy seed oils available. In this investigation solid-phase microextraction (SPME) with DVB/Carboxen/PDMS Stable-Flex fiber was applied to the study of volatile compounds of several seed oil samples from Papaver somniferum L. (Papaveraceae). 1-Pentanol (3.3-4.9%), 1-hexanal (10.9-30.9%), 1-hexanol (5.3-33.7%), 2-pentylfuran (7.2-10.0%), and caproic acid (2.9-11.5%) could be identified as the main volatile compounds in all examined poppy seed oil samples. Furthermore, the TAG composition of these oils was analyzed by MALDI-ReTOF- and ESI-IT-MS/MS. The predominant TAG components were found to be composed of linoleic, oleic, and palmitic acid, comprising approximately 70% of the oils. TAG patterns of the different poppy varieties were found to be very homogeneous, showing also no significant differences in terms of the applied pressing method of the plant seeds. PMID:16218681

  6. Chlorophyll a sensitized redox processes in microemulsion systems

    SciTech Connect

    Kiwi, J.; Gratzel, M.

    1980-06-12

    A chlorophyll-containing microemulsion was prepared on 80% water w/w and sodium hexadecyl sulfate, hexadecane, 1-pentanol, and chlorophyll a. The droplet radius as determined by autocorrelated Rayleigh scattering is 130 angstroms. Using a pulsed ruby laser the chl-a triplet spectrum was measured. It peaks at approximately 465 nm and shows minima due to ground-state bleaching at 430 and 420 nm. Chl-a reduces methyl viologen (MV/sup 2 +/) with a specific rate of 4 x 10/sup 8/ M/sup -1/ sec./sup -1/. At 5 x 10/sup -3/ M MV/sup 2 +/ concentration the efficiency of this process is unity. The cation radical Chl-a/sup +/ reacts with both ascorbate and NADh. In the latter case Chl-a can sensitize irreversible electron transfer from NADh to MV/sup 2 +/. If this system is coupled with a suitable hydrogenation catalyst, hydrogen evolution from water is observed. 34 references.

  7. Can Volatile Organic Metabolites Be Used to Simultaneously Assess Microbial and Mite Contamination Level in Cereal Grains and Coffee Beans?

    PubMed Central

    Salvador, Ângelo C.; Baptista, Inês; Barros, António S.; Gomes, Newton C. M.; Cunha, Ângela; Almeida, Adelaide; Rocha, Silvia M.

    2013-01-01

    A novel approach based on headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC×GC–ToFMS) was developed for the simultaneous screening of microbial and mite contamination level in cereals and coffee beans. The proposed approach emerges as a powerful tool for the rapid assessment of the microbial contamination level (ca. 70 min versus ca. 72 to 120 h for bacteria and fungi, respectively, using conventional plate counts), and mite contamination (ca. 70 min versus ca. 24 h). A full-factorial design was performed for optimization of the SPME experimental parameters. The methodology was applied to three types of rice (rough, brown, and white rice), oat, wheat, and green and roasted coffee beans. Simultaneously, microbiological analysis of the samples (total aerobic microorganisms, moulds, and yeasts) was performed by conventional plate counts. A set of 54 volatile markers was selected among all the compounds detected by GC×GC–ToFMS. Principal Component Analysis (PCA) was applied in order to establish a relationship between potential volatile markers and the level of microbial contamination. Methylbenzene, 3-octanone, 2-nonanone, 2-methyl-3-pentanol, 1-octen-3-ol, and 2-hexanone were associated to samples with higher microbial contamination level, especially in rough rice. Moreover, oat exhibited a high GC peak area of 2-hydroxy-6-methylbenzaldehyde, a sexual and alarm pheromone for adult mites, which in the other matrices appeared as a trace component. The number of mites detected in oat grains was correlated to the GC peak area of the pheromone. The HS-SPME/GC×GC–ToFMS methodology can be regarded as the basis for the development of a rapid and versatile method that can be applied in industry to the simultaneous assessment the level of microbiological contamination and for detection of mites in cereals grains and coffee beans. PMID:23613710

  8. Bacterial Degradation of tert-Amyl Alcohol Proceeds via Hemiterpene 2-Methyl-3-Buten-2-ol by Employing the Tertiary Alcohol Desaturase Function of the Rieske Nonheme Mononuclear Iron Oxygenase MdpJ

    PubMed Central

    Schuster, Judith; Schäfer, Franziska; Hübler, Nora; Brandt, Anne; Rosell, Mònica; Härtig, Claus; Harms, Hauke; Müller, Roland H.

    2012-01-01

    Tertiary alcohols, such as tert-butyl alcohol (TBA) and tert-amyl alcohol (TAA) and higher homologues, are only slowly degraded microbially. The conversion of TBA seems to proceed via hydroxylation to 2-methylpropan-1,2-diol, which is further oxidized to 2-hydroxyisobutyric acid. By analogy, a branched pathway is expected for the degradation of TAA, as this molecule possesses several potential hydroxylation sites. In Aquincola tertiaricarbonis L108 and Methylibium petroleiphilum PM1, a likely candidate catalyst for hydroxylations is the putative tertiary alcohol monooxygenase MdpJ. However, by comparing metabolite accumulations in wild-type strains of L108 and PM1 and in two mdpJ knockout mutants of strain L108, we could clearly show that MdpJ is not hydroxylating TAA to diols but functions as a desaturase, resulting in the formation of the hemiterpene 2-methyl-3-buten-2-ol. The latter is further processed via the hemiterpenes prenol, prenal, and 3-methylcrotonic acid. Likewise, 3-methyl-3-pentanol is degraded via 3-methyl-1-penten-3-ol. Wild-type strain L108 and mdpJ knockout mutants formed isoamylene and isoprene from TAA and 2-methyl-3-buten-2-ol, respectively. It is likely that this dehydratase activity is catalyzed by a not-yet-characterized enzyme postulated for the isomerization of 2-methyl-3-buten-2-ol and prenol. The vitamin requirements of strain L108 growing on TAA and the occurrence of 3-methylcrotonic acid as a metabolite indicate that TAA and hemiterpene degradation are linked with the catabolic route of the amino acid leucine, including an involvement of the biotin-dependent 3-methylcrotonyl coenzyme A (3-methylcrotonyl-CoA) carboxylase LiuBD. Evolutionary aspects of favored desaturase versus hydroxylation pathways for TAA conversion and the possible role of MdpJ in the degradation of higher tertiary alcohols are discussed. PMID:22194447

  9. Can volatile organic metabolites be used to simultaneously assess microbial and mite contamination level in cereal grains and coffee beans?

    PubMed

    Salvador, Angelo C; Baptista, Inês; Barros, António S; Gomes, Newton C M; Cunha, Angela; Almeida, Adelaide; Rocha, Silvia M

    2013-01-01

    A novel approach based on headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-ToFMS) was developed for the simultaneous screening of microbial and mite contamination level in cereals and coffee beans. The proposed approach emerges as a powerful tool for the rapid assessment of the microbial contamination level (ca. 70 min versus ca. 72 to 120 h for bacteria and fungi, respectively, using conventional plate counts), and mite contamination (ca. 70 min versus ca. 24 h). A full-factorial design was performed for optimization of the SPME experimental parameters. The methodology was applied to three types of rice (rough, brown, and white rice), oat, wheat, and green and roasted coffee beans. Simultaneously, microbiological analysis of the samples (total aerobic microorganisms, moulds, and yeasts) was performed by conventional plate counts. A set of 54 volatile markers was selected among all the compounds detected by GC×GC-ToFMS. Principal Component Analysis (PCA) was applied in order to establish a relationship between potential volatile markers and the level of microbial contamination. Methylbenzene, 3-octanone, 2-nonanone, 2-methyl-3-pentanol, 1-octen-3-ol, and 2-hexanone were associated to samples with higher microbial contamination level, especially in rough rice. Moreover, oat exhibited a high GC peak area of 2-hydroxy-6-methylbenzaldehyde, a sexual and alarm pheromone for adult mites, which in the other matrices appeared as a trace component. The number of mites detected in oat grains was correlated to the GC peak area of the pheromone. The HS-SPME/GC×GC-ToFMS methodology can be regarded as the basis for the development of a rapid and versatile method that can be applied in industry to the simultaneous assessment the level of microbiological contamination and for detection of mites in cereals grains and coffee beans. PMID:23613710

  10. Exhalation pattern changes during fasting and low dose glucose treatment in rats.

    PubMed

    Fink, Tobias; Albrecht, Frederic W; Maurer, Felix; Kleber, Astrid; Hüppe, Tobias; Schnauber, Kristina; Wolf, Beate; Baumbach, Jörg I; Volk, Thomas; Kreuer, Sascha

    2015-05-01

    The analysis of exhaled metabolites has become a promising field of research in recent decades. Several volatile organic compounds reflecting metabolic disturbance and nutrition status have even been reported. These are particularly important for long-term measurements, as needed in medical research for detection of disease progression and therapeutic efficacy. In this context, it has become urgent to investigate the effect of fasting and glucose treatment for breath analysis. In the present study, we used a model of ventilated rats that fasted for 12 h prior to the experiment. Ten rats per group were randomly assigned for continuous intravenous infusion without glucose or an infusion including 25 mg glucose per 100 g per hour during an observation period of 12 h. Exhaled gas was analysed using multicapillary column ion-mobility spectrometry. Analytes were identified by the BS-MCC/IMS database (version 1209; B & S Analytik, Dortmund, Germany). Glucose infusion led to a significant increase in blood glucose levels (p?1-pentanol, 1-propanol, and 2-heptanol. Our results indicate that for long-term measurement, fasting and the withholding of glucose could contribute to changes of volatile metabolites in exhaled air. PMID:25808025

  11. Isoform selectivity of adenylyl cyclase inhibitors: characterization of known and novel compounds.

    PubMed

    Brand, Cameron S; Hocker, Harrison J; Gorfe, Alemayehu A; Cavasotto, Claudio N; Dessauer, Carmen W

    2013-11-01

    Nine membrane-bound adenylyl cyclase (AC) isoforms catalyze the production of the second messenger cyclic AMP (cAMP) in response to various stimuli. Reduction of AC activity has well documented benefits, including benefits for heart disease and pain. These roles have inspired development of isoform-selective AC inhibitors, a lack of which currently limits exploration of functions and/or treatment of dysfunctions involving AC/cAMP signaling. However, inhibitors described as AC5- or AC1-selective have not been screened against the full panel of AC isoforms. We have measured pharmacological inhibitor profiles for all transmembrane AC isoforms. We found that 9-(tetrahydro-2-furanyl)-9H-purin-6-amine (SQ22,536), 2-amino-7-(furanyl)-7,8-dihydro-5(6H)-quinazolinone (NKY80), and adenine 9-?-d-arabinofuranoside (Ara-A), described as supposedly AC5-selective, do not discriminate between AC5 and AC6, whereas the putative AC1-selective inhibitor 5-[[2-(6-amino-9H-purin-9-yl)ethyl]amino]-1-pentanol (NB001) does not directly target AC1 to reduce cAMP levels. A structure-based virtual screen targeting the ATP binding site of AC was used to identify novel chemical structures that show some preference for AC1 or AC2. Mutation of the AC2 forskolin binding pocket does not interfere with inhibition by SQ22,536 or the novel AC2 inhibitor, suggesting binding to the catalytic site. Thus, we show that compounds lacking the adenine chemical signature and targeting the ATP binding site can potentially be used to develop AC isoform-specific inhibitors, and discuss the need to reinterpret literature using AC5/6-selective molecules SQ22,536, NKY80, and Ara-A. PMID:24006339

  12. Kinetic limitations on tracer partitioning in ganglia dominated source zones

    NASA Astrophysics Data System (ADS)

    Ervin, Rhiannon E.; Boroumand, Ali; Abriola, Linda M.; Ramsburg, C. Andrew

    2011-11-01

    Quantification of the relationship between dense nonaqueous phase liquid (DNAPL) source strength, source longevity and spatial distribution is increasingly recognized as important for effective remedial design. Partitioning tracers are one tool that may permit interrogation of DNAPL architecture. Tracer data are commonly analyzed under the assumption of linear, equilibrium partitioning, although the appropriateness of these assumptions has not been fully explored. Here we focus on elucidating the nonlinear and nonequilibrium partitioning behavior of three selected alcohol tracers — 1-pentanol, 1-hexanol and 2-octanol in a series of batch and column experiments. Liquid-liquid equilibria for systems comprising water, TCE and the selected alcohol illustrate the nonlinear distribution of alcohol between the aqueous and organic phases. Complete quantification of these equilibria facilitates delineation of the limits of applicability of the linear partitioning assumption, and assessment of potential inaccuracies associated with measurement of partition coefficients at a single concentration. Column experiments were conducted under conditions of non-equilibrium to evaluate the kinetics of the reversible absorption of the selected tracers in a sandy medium containing a uniform entrapped saturation of TCE-DNAPL. Experimental tracer breakthrough data were used, in conjunction with mathematical models and batch measurements, to evaluate alternative hypotheses for observed deviations from linear equilibrium partitioning behavior. Analyses suggest that, although all tracers accumulate at the TCE-DNAPL/aqueous interface, surface accumulation does not influence transport at concentrations typically employed for tracer tests. Moreover, results reveal that the kinetics of the reversible absorption process are well described using existing mass transfer correlations originally developed to model aqueous boundary layer resistance for pure-component NAPL dissolution.

  13. Volatiles in raw and cooked meat from lambs fed olive cake and linseed.

    PubMed

    Gravador, R S; Serra, A; Luciano, G; Pennisi, P; Vasta, V; Mele, M; Pauselli, M; Priolo, A

    2015-04-01

    This study was conducted to determine the effects of feeding olive cake and linseed to lambs on the volatile organic compounds (VOCs) in raw and cooked meat. Four groups of eight male Appenninica lambs each were fed: conventional cereal-based concentrates (diet C), concentrates containing 20% on a dry matter (DM) basis of rolled linseed (diet L), concentrates containing 35% DM of stoned olive cake (diet OC), or concentrates containing both rolled linseed (10% DM) and stoned olive cake (17% DM; diet OCL). The longissimus dorsi muscle of each lamb was sampled at slaughter and was subjected to VOC profiling through the use of SPME-GC-MS. In the raw meat, the concentration of 3-methylpentanoic acid was higher in treatment C as compared with treatments L, OC and OCL (P<0.01). Moreover the level of nonanoic acid was greater in treatments C and OC than in treatment L (P<0.05). With respect to alcohols, in raw meat the amount of 2-phenoxyethanol in treatment OCL was lower than in treatments C (P<0.01) and OC (P<0.05), while in cooked meat the amount of 1-pentanol was higher in treatment C than in treatment OC (P<0.05). Apart from these compounds, none of the lipid oxidation-derived volatiles was significantly affected by the dietary treatment. Therefore, the results suggest that the replacement of cereal concentrates with linseed and/or olive cake did not cause appreciable changes in the production of volatile organic compounds in lamb meat. PMID:25387868

  14. Analysis of thiabendazole, 4-tert-octylphenol and chlorpyrifos in waste and sewage water by direct injection - micellar liquid chromatography.

    PubMed

    Romero-Cano, Ricard; Kassuha, Diego; Peris-Vicente, Juan; Roca-Genovés, Pasqual; Carda-Broch, Samuel; Esteve-Romero, Josep

    2015-03-01

    A micellar liquid chromatographic method has been developed for the simultaneous quantification of the pesticides thiabendazole and chlorpyrifos, as well as an alkylphenol, which is included in pesticide formulations, i.e., 4-tert-octylphenol, in water. A sample was filtered and directly injected, avoiding large extraction steps using toxic solvents, thus expediting the experimental procedure. The contaminants were eluted without interferences in <17 min, using a mobile phase of 0.15 M sodium dodecyl sulfate - 6% 1-pentanol buffered at pH 3, running through a C18 column at 1 mL min(-1) under the isocratic mode. This optimal mobile phase was selected using a statistical approach, which considers the retention factor, efficiency and peak shape of the analytes measured in only a few mobile phases. The detection was carried out by measuring absorbance at 220 nm. The method was successfully validated in terms of specificity, calibration range (0.5-10 mg L(-1)), linearity (r(2) > 0.994), limit of detection and quantification (0.2-0.3; and 0.5-0.8 mg L(-1), respectively), intra- and interday accuracy (95.2-102.9%), precision (<8.3%), and ruggedness (<9.3%). The stability in storage conditions (at least 14 days) was studied. The method was safe, inexpensive, produced little pollutant and has a short analysis time, thus it is useful for the routine analysis of samples. Finally, the method was applied to analyse wastewater from the fruit-processing industry, wastewater treatment plants, and in sewage water belonging to the Castelló area (Spain). The results were similar to those obtained by an already reliable method. PMID:25604004

  15. An examination of the H/D isotope substitution effect on selectivity and activity in the cavitating ultrasound hydrogenation of aqueous 3-buten-2-ol and 1,4-pentadien-3-ol on Pd-black

    SciTech Connect

    Boyles, Kelly R.; Chajkowski, Sarah M.; Disselkamp, Robert S.; Peden, Charles HF

    2006-05-24

    An H/D isotope effect study of the (H2 versus D2) hydrogenation of the aqueous substrates 3-buten-2-ol (3B2OL) and 1,4-pentadien-3-ol (14PD3OL) was performed using Pd-black catalyst. Either H2O or D2O solvents were employed (for alcohol H/D isotope substitution). Two experimental processing conditions of cavitating ultrasound (CUS) and stirred/silent (SS) methods were used. Products formed include 2-butanol and 2-butanone for the former, and 3-pentanol and 3-pentanone for the latter. The observed selectivity and pseudo-first order reaction rate coefficients (e.g., activity) to these products enabled a mechanistic interpretation of the various reaction conditions to be proposed. Experiments utilized a 50 mL batch reactor maintained at 298 K, employed 5.4 atm of H2 or D2 gas, while seven aliquots were collected during the course of the reaction. We have utilized 1-propanol as an inert dopant in all experiments to enable the rapid onset of cavitation in the CUS systems as described earlier [R.S. Disselkamp et al., J. Catal., 227, 552 (2004)]. The following conclusions were noted. First, the activity of the CUS compared to SS processing were ~100-fold larger. Second, variable catalyst loading experiments for stirred/silent D2 hydrogenation processing indicated that mass transfer of hydrogen gas to the Pd-surface played a role such that higher catalyst loading reduced surface D-atom concentrations and reduced saturated alcohol formation (e.g., via reduced H-addition to surface alkyl radicals). Third, for CUS processing the ketone selectivities for experiments employing water compared to D2O indicated that 3B2OL were twice as large, whereas for 14PD3OL they were comparable. This suggests, somewhat surprisingly, that for 3B2OL enol tautomerization to ketone is a slow, and possibly rate-controlling, process. Finally, again for CUS processing, the similarity in ketone selectivities (all ~17%) for H2 compared to D2 hydrogenation for both 3B2OL and 14PD3OL suggest that both H/D isotopes have rapid surface diffusion and hence give rise to nearly equal selectivies. Restated, the thermal or cavitating ultrasound activation is much greater than the surface H/D diffusion barrier.

  16. Thermoanaerobacter yonseiensis sp. nov., a novel extremely thermophilic, xylose-utilizing bacterium that grows at up to 85 degrees C.

    PubMed

    Kim, B C; Grote, R; Lee, D W; Antranikian, G; Pyun, Y R

    2001-07-01

    A novel strictly anaerobic, extremely thermophilic, spore-forming and xylose-utilizing bacterium, designated strain KB-1TP (type and patent strain), was isolated from a geothermal hot stream at Sileri on Java island, Indonesia. The cells were rod-shaped, motile and had terminal spores. The newly isolated strain stained gram-positive and the cells occurred singly or in pairs during the exponential growth phase. The temperature optimum for growth was 75 degrees C and growth occurred in the range 50-85 degrees C. The pH range for growth was 4.5-9.0, with an optimum at pH 6.5. Strain KB-1TP grew chemo-organotrophically by fermenting a wide range of substrates such as glucose, fructose, D-xylose, lactose, maltose, sucrose, mannose, galactose, cellobiose, pullulan and soluble starch. Arabinose, xylan, cellulose, olive oil and Tween 80 were not fermented. The predominant fermentation end products after growth on glucose were lactate, acetate, ethanol, CO2 and small amounts of isovaleric acid, butyric acid, propionic acid, 1-pentanol and 2-propanol. Thiosulfate was reduced to H2S. Strain KB-1TP was sensitive to tetracycline, chloramphenicol, penicillin G, neomycin, kanamycin, vancomycin and rifampicin at concentrations of 100 microg ml(-1). No effect was observed with chloramphenicol and neomycin at concentrations of 10 microg ml(-1). This indicates that strain KB-1TP belongs to the bacterial domain. The G+C content of the DNA was 37 mol%. The comparison of the 165 rDNA sequence to that of closely related strains revealed that strain KB-1TP belonged to clostridial cluster V, showing highest sequence identities (92.7%) to members of the genus Thermoanaerobacter. Taking into account the physiological and molecular properties of the new isolate, it is proposed that strain KB-1TP should be classified as a new species of the genus Thermoanaerobacter, designated Thermoanaerobacter yonseiensis. The type strain, KB-1TP, has been deposited in the Korean Federation of Culture Collections (KFCC 11116P) as a patent strain and in the Deutsche Sammlung von Mikroorganismen und Zellkulturen as a type strain (= DSM 13777T). PMID:11491356

  17. The effect of cavitating ultrasound on the aqueous phase hydrogenation of cis-2-buten-1-ol and cis-2-penten-1-ol on Pd-black

    SciTech Connect

    Disselkamp, Robert S.; Denslow, Kayte M.; Hart, Todd R.; White, James F.; Peden, Charles HF.

    2005-07-15

    We have studied the effect of cavitating ultrasound on the heterogeneous aqueous hydrogenation of cis-2-buten-1-ol (C4 olefin) and cis-2-penten-1-ol (C5 olefin) on Pd-black to form the trans-olefins (trans-2-buten-1-ol and trans-2-penten-1-ol) and saturated alcohols (1-butanol and 1-pentanol, respectively). Silent (and magnetically stirred) experiments served as control experiments. As described in an earlier publication by our group, we have added an inert dopant, 1-propanol, in the reaction mixture to ensure the rapid onset of cavitation in the ultrasound-assisted reactions that can lead to altered selectivity compared to silent reaction systems [R.S. Disselkamp, Ya-Huei Chin, C.H.F. Peden, J. Catal. 227 (2004) 552]. The motivation for this study is to examine whether cavitating ultrasound can reduce the [trans-olefin/saturated alcohol] molar ratio during the course of the reaction. This could have practical application in that it may offer an alternative processing methodology of synthesizing healthier edible seed oils by reducing trans-fat content.We have observed that cavitating ultrasound results in a [(trans-olefin/saturated alcohol)ultrasound/(trans-olefin/saturated alcohol)silent] ratio quantity less than 0.5 at the reaction mid-point for both the C4 and C5 olefin systems. This indicates that ultrasound reduces trans-olefin production compared to the silent control experiment. Furthermore, there is an added 30% reduction for the C5 versus C4 olefin compounds again at reaction mid-point. We attribute differences in the ratio quantity as a moment of inertia effect. In principle, the C4 versus C5 olefins has a {approx}52% increase in moment of inertia about C2 C3 double bond slowing isomerization. Since seed oils are C18 multiple cis-olefins and have a moment of inertia even greater than our C5 olefin here, our study suggests that even a greater reduction in trans-olefin content may occur for partial hydrogenation of C18 seed oils.

  18. The Effect of Cavitating Ultrasound on the Aqueous Phase Hydrogenation of Cis-2-buten-1-ol and Cis-2-penten-1-ol on Pd-black

    SciTech Connect

    Disselkamp, Robert S.; Denslow, Kayte M.; Hart, Todd R.; White, James F.; Peden, Charles HF.

    2005-07-15

    We have studied the effect of cavitating ultrasound on the heterogeneous aqueous hydrogenation of cis-2-buten-1-ol (C4 olefin) and cis-2-penten-1-ol (C5 olefin) on Pd-black to form the trans-olefins (trans-2-buten-1-ol and trans-2-penten-1-ol) and saturated alcohols (1-butanol and 1-pentanol, respectively). Silent (and magnetically stirred) experiments served as control experiments. As described in an earlier publication by our group, we have added an inert dopant, 1-propanol, in the reaction mixture to ensure the rapid onset of cavitation in the ultrasound-assisted reactions that can lead to altered selectivity compared to silent reaction systems [Disselkamp et al., J. Catal., 227 (2004) 552]. The motivation for this study is to examine whether cavitating ultrasound can reduce the [trans-olefin/saturated alcohol] molar ratio during the course of the reaction. This could have practical application in that it may offer an alternative processing methodology of synthesizing healthier edible seed oils by reducing trans-fat content. We have observed that cavitating ultrasound results in a [(trans-olefin/saturated alcohol)ultrasound/(trans-olefin/saturated alcohol)silent] ratio quantity less than 0.5 at the reaction mid-point for both the C4 and C5 olefin systems. This indicates that ultrasound reduces trans-olefin production compared to the silent control experiment. Furthermore, there is an added 30% reduction for the C5 versus C4 olefin compounds again at reaction mid-point. We attribute differences in the ratio quantity as a moment of inertia effect. In principle, the C4 versus C5 olefins has a {approx}52% increase in moment of inertia about C2=C3 double bond slowing isomerization. Since seed oils are C18 multiple cis olefins and have an moment of inertia even greater than our C5 olefin here, our study suggests that even a greater reduction in trans-olefin content may occur for partial hydrogenation of C18 seed oils.

  19. Experimental study of the effect of test-well arrangement for partitioning interwell tracer test on the estimation of NAPL saturation

    NASA Astrophysics Data System (ADS)

    Kim, B.; Kim, Y.; Yeo, I.; Yongcheol Kim, In Wook Yeo

    2011-12-01

    Partitioning interwell tracer test (PITT) is a method to quantify and qualify a contaminated site with NAPLs through a degree of retardation of partitioning tracers compared to a conservative one. Although PITT is known to be a more effective method to measure the saturation of spatially-distributed NAPL contaminant than the point investigation method, the saturation estimation from PITT is reported to be underestimated due to various factors including heterogeneity of the media, adsorption, source zone NAPL architecture, and long tailing in breakthrough curves of partitioning tracers. Analytical description of PITT assumes that the injection-pumping well pair is on the line of ambient groundwater flow direction, but the test-well pair could easily be off the line in the field site, which could be another erroneous factor in analyzing PITT data. The purpose of this work is to study the influence of the angle of the test-well pair to ambient groundwater flow direction based on the result from PITT. The experiments were conducted in a small-scale 3D sandbox with dimensions of 0.5 m × 0.4 m × 0.15 m (LWH) of stainless steel. The surface is covered and sealed with a plexiglass plate to make the physical model a confined aquifer. Eight full-screened wells of Teflon material were installed along the perimeter of a 50 mm circle with 45 degree intervals in the middle of the physical model. Both ends of the sand box are connected to constant head reservoirs. The physical model was wet-packed with sieved and washed sand. Trichloroethylene (TCE) and bromide were used as the contaminant and the conservative tracer, respectively. Hexanol, 2,4-dimethyl-3-pentanol and 6-methyl-2-heptanol were used as partitioning tracers. Before the injection of TCE, a PITT was conducted to measure adsorption coefficient of partitioning tracers to the sand material. TCE of 4.5 mL, dyed with Sudan IV, was injected into the inner part of the circle of the wells. PITTs using the test-well pair parallel and with angles of 45 and 90 degrees to ambient flow direction were performed. Another PITT was conducted at an increased pumping rate with the test-well pair at a 45 degree angle to examine the effect of pumping rate. From the experiments, it was found that as the angles of the test-well pair to ambient groundwater flow direction increased, the estimated NAPL saturation decreased. Although the increase in pumping rate in this experiment reduces the effect of the obliqueness of the test-well arrangement, the effect of rate-limited transfer of partitioning tracers due to the increased pumping rate on the PITT should be examined in the interpretation. The results of these experiments revealed that the arrangement of the test-well pair is another controlling factor in performing and interpreting PITT in the field, in addition to the factors such as heterogeneity, source zone architecture, and tailing. Key words: PITT, test-well arrangement, ambient groundwater flow direction, NAPL saturation Acknowledgements: This research was supported by the Basic Research Project of the Korea Institute of Geoscience and Mineral Resources (KIGAM) funded by the Ministry of Knowledge Economy of Korea. 11-3414

  20. Safety assessment of MIBK (methyl isobutyl ketone).

    PubMed

    Johnson, Wilbur

    2004-01-01

    MIBK (Methyl Isobutyl Ketone) is an aliphatic ketone that functions as both a denaturant and solvent in cosmetic products. Current use in cosmetic products is very limited, but MIBK is reported to be used in one nail correction pen (volume = 3 ml) at a concentration of 21%. The maximum percutaneous absorption rate in guinea pigs is 1.1 micromol/min/cm2 at 10 to 45 min. Metabolites include 4-hydroxy-4-methyl-2-pentanone (oxidation product) and 4-methyl-2-pentanol (4-MPOL) (reduction product). Values for the serum half-life and total clearance time of MIBK in animals were 66 min and 6 h, respectively. In clinical tests, most of the absorbed MIBK had been eliminated from the body 90 min post exposure. MIBK was not toxic via the oral or dermal route of exposure in acute, short-term, or subchronic animal studies, except that nephrotoxicity was observed in rats dosed with 1 g/kg in a short-term study. MIBK was an ocular and skin irritant in animal tests. Ocular irritation was noted in 12 volunteers exposed to 200 ppm MIBK for 15 min in a clinical test. A depression of the vestibulo-oculomotor reflex was seen with intravenous infusion of MIBK (in an emulsion) at 30 microM/kg/min in female rats. The no-observed-effect level in rats exposed orally to MIBK was 50 mg/kg. Both gross and microscopic evidence of lung damage were reported in acute inhalation toxicity studies in animals. Short-term and subchronic inhalation exposures (as low as 100 ppm) produced effects in the kidney and liver that were species and sex dependent. Dermal doses of 300 or 600 mg/kg for 4 months in rats produced reduced mitotic activity in hair follicles, increased thickness of horny and granular cell layers of the epidermis, a decrease in the number of reactive centers in follicles (spleen), an increase in the number of iron-containing pigments in the area of the red pulp (spleen), and a reduction in the lipid content of the cortical layer of the adrenal glands. Neuropathological changes in the most distal portions of the tibial and ulnar nerves were observed in young adult rats which inhaled 1500 ppm MIBK for up to 5 months. No adverse effects were seen in any other neurological end point by any route of exposure in other studies using rats or other animal species. Clinical tests demonstrated a threshold for MIBK-induced irritation of the lungs at 0.03 to 0.1 mg/L after 1 min of respiration. MIBK was not mutagenic in the Ames test or in a mitotic gene-conversion assay in bacteria. Mammalian mutagenicity test results were also negative in the following assays: mouse lymphoma, unscheduled DNA synthesis, micronucleus, cell transformation, and chromosome damage. MIBK did not induce any treatment-related increases in embryotoxicity or fetal malformations in pregnant Fischer 344 rats or CD-1 mice that inhaled MIBK at concentrations of 300, 1000, or 3000 ppm. There was evidence of treatment-related maternal toxicity only at the highest concentration tested. MIBK applied to the tail of rats daily at doses of 300 or 600 mg/kg for 4 months produced changes in the testes, including a reduction in the number of spermatocytes, spermatids, and spermatozoa. An ongoing carcinogenicity study of MIBK being conducted by the National Toxicology Program will be considered when the results are available. On the basis of the information that is currently available, MIBK is considered safe as used in nail polish removers and as an alcohol denaturant in cosmetic products. PMID:15162837

  1. A Unique Equation to Estimate Flash Points of Selected Pure Liquids Application to the Correction of Probably Erroneous Flash Point Values

    NASA Astrophysics Data System (ADS)

    Catoire, Laurent; Naudet, Valérie

    2004-12-01

    A simple empirical equation is presented for the estimation of closed-cup flash points for pure organic liquids. Data needed for the estimation of a flash point (FP) are the normal boiling point (Teb), the standard enthalpy of vaporization at 298.15 K [?vapH°(298.15 K)] of the compound, and the number of carbon atoms (n) in the molecule. The bounds for this equation are: -100?FP(°C)?+200; 250?Teb(K)?650; 20??vap H°(298.15 K)/(kJ mol-1)?110; 1?n?21. Compared to other methods (empirical equations, structural group contribution methods, and neural network quantitative structure-property relationships), this simple equation is shown to predict accurately the flash points for a variety of compounds, whatever their chemical groups (monofunctional compounds and polyfunctional compounds) and whatever their structure (linear, branched, cyclic). The same equation is shown to be valid for hydrocarbons, organic nitrogen compounds, organic oxygen compounds, organic sulfur compounds, organic halogen compounds, and organic silicone compounds. It seems that the flash points of organic deuterium compounds, organic tin compounds, organic nickel compounds, organic phosphorus compounds, organic boron compounds, and organic germanium compounds can also be predicted accurately by this equation. A mean absolute deviation of about 3 °C, a standard deviation of about 2 °C, and a maximum absolute deviation of 10 °C are obtained when predictions are compared to experimental data for more than 600 compounds. For all these compounds, the absolute deviation is equal or lower than the reproductibility expected at a 95% confidence level for closed-cup flash point measurement. This estimation technique has its limitations concerning the polyhalogenated compounds for which the equation should be used with caution. The mean absolute deviation and maximum absolute deviation observed and the fact that the equation provides unbiaised predictions lead to the conclusion that several flash points have been reported erroneously, whatever the reason, in one or several reference compilations. In the following lists, the currently accepted flash points for bold compounds err, or probably err, on the hazardous side by at least 10 °C and for the nonbolded compounds, the currently accepted flash points err, or probably err, on the nonhazardous side by at least 10 °C: bicyclohexyl, sec-butylamine, tert-butylamine, 2-cyclohexen-1-one, ethanethiol, 1,3-cyclohexadiene, 1,4-pentadiene, methyl formate, acetonitrile, cinnamaldehyde, 1-pentanol, diethylene glycol, diethyl fumarate, diethyl phthalate, trimethylamine, dimethylamine, 1,6-hexanediol, propylamine, methanethiol, ethylamine, bromoethane, 1-bromopropane, tert-butylbenzene, 1-chloro-2-methylpropane, diacetone alcohol, diethanolamine, 2-ethylbutanal, and formic acid. For some other compounds, no other data than the currently accepted flash points are available. Therefore, it cannot be assessed that these flash point data are erroneous but it can be stated that they are probably erroneous. At least, they need experimental re-examination. They are probably erroneous by at least 15 °C: 1,3-cyclopentadiene, di-tert-butyl sulfide, dimethyl ether, dipropyl ether, 4-heptanone, bis(2-chloroethyl)ether, 1-decanol, 1-phenyl-1-butanone, furan, ethylcyclopentane, 1-heptanethiol, 2,5-hexanediol, 3-hexanone, hexanoic acid methyl ester, 4-methyl-1,3-pentadiene, propanoyl chloride, tetramethylsilane, thiacyclopentane, 1-chloro-2-methyl-1-propene, trans-1,3-pentadiene, 2,3-dimethylheptane, triethylenetetramine, methylal, N-ethylisopropylamine, 3-methyl-2-pentene, and 2,3-dimethyl-1-butene.