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Sample records for acetone chloroform ethyl

  1. Solute-solvent complex switching dynamics of chloroform between acetone and dimethylsulfoxide-two-dimensional IR chemical exchange spectroscopy.

    PubMed

    Kwak, Kyungwon; Rosenfeld, Daniel E; Chung, Jean K; Fayer, Michael D

    2008-11-01

    Hydrogen bonds formed between C-H and various hydrogen bond acceptors play important roles in the structure of proteins and organic crystals, and the mechanisms of C-H bond cleavage reactions. Chloroform, a C-H hydrogen bond donor, can form weak hydrogen-bonded complexes with acetone and with dimethylsulfoxide (DMSO). When chloroform is dissolved in a mixed solvent consisting of acetone and DMSO, both types of hydrogen-bonded complexes exist. The two complexes, chloroform-acetone and chloroform-DMSO, are in equilibrium, and they rapidly interconvert by chloroform exchanging hydrogen bond acceptors. This fast hydrogen bond acceptor substitution reaction is probed using ultrafast two-dimensional infrared (2D-IR) vibrational echo chemical exchange spectroscopy. Deuterated chloroform is used in the experiments, and the 2D-IR spectrum of the C-D stretching mode is measured. The chemical exchange of the chloroform hydrogen bonding partners is tracked by observing the time-dependent growth of off-diagonal peaks in the 2D-IR spectra. The measured substitution rate is 1/30 ps for an acetone molecule to replace a DMSO molecule in a chloroform-DMSO complex and 1/45 ps for a DMSO molecule to replace an acetone molecule in a chloroform-acetone complex. Free chloroform exists in the mixed solvent, and it acts as a reactive intermediate in the substitution reaction, analogous to a SN1 type reaction. From the measured rates and the equilibrium concentrations of acetone and DMSO, the dissociation rates for the chloroform-DMSO and chloroform-acetone complexes are found to be 1/24 ps and 1/5.5 ps, respectively. The difference between the measured rate for the complete substitution reaction and the rate for complex dissociation corresponds to the diffusion limited rate. The estimated diffusion limited rate agrees well with the result from a Smoluchowski treatment of diffusive reactions. PMID:18855462

  2. Chloroform

    Integrated Risk Information System (IRIS)

    Chloroform ; CASRN 67 - 66 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effects

  3. Acetone

    Integrated Risk Information System (IRIS)

    Acetone ; CASRN 67 - 64 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effects )

  4. Improved Gas Chromatographic Determination of Guanidino Compounds Using Isovaleroylacetone and Ethyl Chloroformate as Derivatizing Reagents.

    PubMed

    Zounr, Rizwan Ali; Khuhawar, Mumammad Yar; Jahangir, Taj Muhammad; Alamgir, Malik

    2016-01-01

    An improved GC method in terms of sensitivity and decrease in the analysis time has been developed for the analysis of eight guanidino compounds: guanidine (G), methylguanidine (MG), creatinine (CTN), guanidinoacetic acid (GAA), guanidinobutyric acid (GBA), guanidinopropionic acid (GPA), argenine (Arg), and guanidinosuccinic acid (GSA), using isovaleroylacetone (IVA) and ethyl chloroformate (ECF) as derivatizing reagents. The separation was obtained from column HP-5 (30 m × 0.32 mm i.d.) with film thickness of 0.25 μm within 11 min. The linear calibrations were obtained with 0.5 to 50 μg/mL with coefficient of determination (R(2)) within 0.9969 - 0.9998. Limits of detections (LODs) were within 5 - 140 ng/mL. The derivatization, separation and determination was repeatable (n = 6) with relative standard deviation (RSD) within 1.2 - 3.1%. The guanidino compounds were determined in deproteinized serum of healthy volunteers and uremic patients within below LOD to 8.8 μg/mL and below LOD to 43.99 μg/mL with RSD within 1.4 - 3.6%. The recovery of guanidino compounds calculated by standard addition from serum was within 96.1 - 98.9%, with RSD 1.4 - 3.6%. PMID:26860556

  5. The enthalpies and entropies of pefloxacin dissolution in methanol, ethanol, 1-Propanol, 2-Propanol, acetone, and chloroform at 293.15-323.15 K

    NASA Astrophysics Data System (ADS)

    Zhang, C.-L.; Cui, S.-J.; Wang, Y.

    2012-12-01

    The solubilities of pefloxacin in methanol, ethanol, 1-propanol, 2-propanol, acetone, and chloroform have been determined from 293.15 to 323.15 K by a static equilibrium method. The experimental data were correlated with the modified Apelblat equation. The positive Δsol H and Δsol S for each system revealed that pefloxacin dissolution in each solvent is an entropy-driven process.

  6. Liquid acetone and chloroform: a comparison between Monte Carlo simulation, molecular Ornstein-Zernike theory, and site-site Ornstein-Zernike theory

    NASA Astrophysics Data System (ADS)

    Richardi, J.; Fries, P. H.; Fischer, R.; Rast, S.; Krienke, H.

    Site-site distribution functions, internal energies, compressibilities, and dielectric constants of liquid acetone and chloroform are computed and compared. The hypernetted chain approximation is used for the molecular Ornstein-Zernike (MOZ) and site-site Ornstein-Zernike (SSOZ) theories. Both solvent molecules are described as sets of interaction sites, which are the centres of Lennard-Jones potentials and which carry partial electric charges. How the approximations inherent in both OZ theories affect the calculated liquid properties is discussed. In contrast to SSOZ theory, MOZ theory yields a correct description of the liquid structure as defined by the site-site distribution functions of simulations. The MOZ results for the dielectric constants are in good agreement with simulation, but both OZ theories slightly underestimate the internal excess energies. In contrast to the SSOZ formalism and to the simulations, the molecular pair distribution of MOZ theory can be computed readily for all two-molecule configurations, allowing a detailed study of the complex relief of this distribution. A search was performed for configurations that are highly probable in the liquid. They can be assigned to a small number of peaks of the molecular distribution function. These peaks have major contributions to the Kirkwood factors, which measure the orientational order in the liquid, and to the electrostatic part of the excess energies. The partitioning of the whole two-molecule configuration space makes it possible to study the details of the site-site distribution functions. For instance, a sharp peak in the oxygen-oxygen distribution in acetone results from many superimposed contributions of acetone-acetone arrangements of low and medium statistical weights, and not from the highly probable arrangements.

  7. The effects of chloroform, ethyl acetate and methanolic extracts of Brassica rapa L. on cell-mediated immune response in mice

    PubMed Central

    Jafarian-Dehkordi, A.; Zolfaghari, B.; Mirdamadi, M.

    2013-01-01

    Turnips with a long history of usage, are helpful in preventing breast and prostate cancer, inflammation and body`s immune system dysfunction. In this study, we investigated the effects of chloroform, ethyl acetate and methanolic extracts of Brassica rapa L. on cell-mediated immune response in mice. Chloroform, ethyl acetate and methanolic extracts of B. rapa glands were prepared by maceration method. To study the effects of B. rapa on acquired immunity, groups of Balb/c mice (n=8) were used. Sheep red blood cell (SRBC) was injected (s.c., 1×108cells/ml, 0.02 ml) and 5 days later, different extracts (10, 100 and 500 mg/kg), betamethasone (4 mg/kg) and Levamisol (4 mg/kg) as a positive control and normal saline as a negative control were given i.p. After 1 h SRBC was injected to footpad (s.c., 1×108cells/ml, 0.02 ml) and footpad swelling was measured up to 72 h. To investigate the effects of B. rapa on innate immunity the same procedure was used, but animals only received one injection of SRBC 1 h after i.p. injection of test compounds. Our findings showed that SRBC induced an increase in paw swelling with maximum response at 6-8 and 2-4 h for innate and acquired immunity, respectively. Betamethasone inhibited and levamisol increased paw thickness in both models. In both innate and acquired immunity models, chloroform, ethyl acetate and methanolic extracts of B. rapa glands significantly and dose-dependently reduced paw thickness. Ethyl acetate extract showed better effect. As glucosinolates are better extracted by ethyl acetate, it may be concluded that they are contributed in the more pronounced effects of ethyl acetate extract. PMID:24019825

  8. In vitro ovicidal assessment of methanol, ethyl acetate and chloroform extracts of Annona squamosa and Chenopodium album against caprine gastrointestinal nematodiosis.

    PubMed

    Sachan, Arti; Shanker, Daya; Jaiswal, Amit Kumar; Sudan, Vikrant

    2015-03-01

    The objective of this study was in vitro evaluation of the ovicidal efficacy of methanol, ethyl acetate and chloroform extracts of Annona squamosa (seeds) and Chenopodium album (whole plant) in comparison to albendazole against the GI nematodes of goats using egg hatch test. Eggs of GI nematodes were incubated at 27 °C in different extracts at concentration of 100-6.25 mg/ml for 2 days. Distilled water and albendazole were used as negative and positive controls, respectively. Percentage efficacy and ED50 and ED90 values were separately evaluated with upper and lower confidence limit by log probit analysis using SAS 9.2. The ED50 and ED90 values of methanolic, ethyl acetate and chloroform extracts of A. squamosa was calculated as 1.52 and 4.56; 2.48 and 10.73; 3.02 and 12.44 mg/ml, respectively against GI nematodes if goats. Similarly, the ED50 and ED90 values of methanolic, ethyl acetate and chloroform extracts of C. album was calculated as 3.86 and 7.14; 2.73 and 8.31; 4.41 and 20.11 mg/ml, respectively This study shows that C. album and A. squamosa possess in vitro anthelmintic activities. The study also suggests further large scale pharmacological and toxicological studies for their safer use in veterinary medicine. PMID:25698862

  9. β-Keto esters from ketones and ethyl chloroformate: a rapid, general, efficient synthesis of pyrazolones and their antimicrobial, in silico and in vitro cytotoxicity studies

    PubMed Central

    2013-01-01

    Background Pyrazolones are traditionally synthesized by the reaction of β-keto esters with hydrazine and its derivatives. There are methods to synthesize β-keto esters from esters and aldehydes, but these methods have main limitation in varying the substituents. Often, there are a number of methods such as acylation of enolates in which a chelating effect has been employed to lock the enolate anion using lithium and magnesium salts; however, these methods suffer from inconsistent yields in the case of aliphatic acylation. There are methods to synthesize β-keto esters from ketones like caboxylation of ketone enolates using carbon dioxide and carbon monoxide sources in the presence of palladium or transition metal catalysts. Currently, the most general and simple method to synthesize β-keto ester is the reaction of dimethyl or ethyl carbonate with ketone in the presence of strong bases which also requires long reaction time, use of excessive amount of reagent and inconsistent yield. These factors lead us to develop a simple method to synthesize β-keto esters by changing the base and reagent. Results A series of β-keto esters were synthesized from ketones and ethyl chloroformate in the presence of base which in turn are converted to pyrazolones and then subjected to cytotoxicity studies towards various cancer cell lines and antimicrobial activity studies towards various bacterial and fungal strains. Conclusion The β-keto esters from ethyl chloroformate was successfully attempted, and the developed method is simple, fast and applicable to the ketones having the alkyl halogens, protecting groups like Boc and Cbz that were tolerated and proved to be useful in the synthesis of fused bicyclic and tricyclic pyrazolones efficiently using cyclic ketones. Since this method is successful for different ketones, it can be useful for the synthesis of pharmaceutically important pyrazolones also. The synthesized pyrazolones were subjected to antimicrobial, docking and

  10. Gas chromatographic analysis of guanidino compounds in sera and urine of uremic patients using glyoxal and ethyl chloroformate as derivatizing reagents.

    PubMed

    Majidano, Subhan Ali; Khuhawar, Muhammad Yar

    2013-01-01

    Gas chromatographic (GC) method has been developed for the determination of the guanidino compounds: guanidine (G), methylguanidine (MG), guanidinoacetic acid (GAA), guanidinopropionic acid (GPA), guanidinobutyric acid (GBA) and guanidinosuccinic acid (GSA) was carried out after precolumn derivatization with glyoxal and ethyl chloroformate from the column HP-5 (30 m × 0.32 mm i.d.) at 90°C for 3 min, followed by a heating rate 25°C/min up to 260°C with a nitrogen flow rate of 2 ml/min. Detection was by FID. The linear calibrations were obtained within 0.1-20.0 μmol/L, with limits of detection (LODs) within 0.014-0.024 μmol/L. The separation and derivatization was repeatable (n = 6) with relative standard deviations (RSD) within 0.8-1.9% in retention time and 0.5-1.8% in peak height/peak area. A number of additives and amino acids did not affect the determination. The method was applied for the determination of guanidino compounds from the serum and urine of 9 healthy volunteers and 8 uremic patients and the amounts found were in the range 0.08-0.48 and below the limit of detection (LOD) - 345 μmol/L and 1.82 - 13.88 and 0.77 - 432.0 μmol/L with RSDs within 4.2%, respectively. PMID:23400288

  11. Spectrophotometric determination of boron in iron and steel with curcumin after separation by 2-ethyl-1,3-hexanediol-chloroform extraction.

    PubMed

    Donaldson, E M

    1981-11-01

    A simple and reliable method for determining approximately 0.0001% or more of total boron in iron and low- and high-alloy steels is described. After the sample is decomposed at <70 degrees in the presence of hydrogen peroxide and potassium hydrogen fluoride, the insoluble material is filtered off and ultimately fused with sodium carbonate. The cooled melt is dissolved in dilute hydrochloric acid and the solution is combined with the main solution. Fluoride is subsequently complexed with zirconium and boron is separated from iron and other elements by extraction as borate from 1M sulphuric acid medium into chloroform containing 2-ethyl-1,3-hexanediol. Boron, in a 1-ml portion of the extract, is ultimately determined spectrophotometrically at 550 nm in an ethanol medium, after formation of the curcumin rosocyanin complex in a glacial acetic acid-concentrated sulphuric acid medium. Acid-soluble and acid-insoluble boron can also be determined. Common ions, including large amounts of manganese, chromium, vanadium, titanium, molybdenum, tungsten, niobium and tantalum do not interfere. PMID:18963014

  12. Methyl chloroform

    SciTech Connect

    Wray, T.K.

    1994-04-01

    Methyl chloroform is identified as a Class 1 ozone-depleting substance under Title VI of the CAA Amendments. On Nov. 30, 1993, EPA ordered the phaseout of Class 1 ozone-depleting substances -- chlorofluorocarbons (CFCs), halons, carbon tetrachloride and methyl chloroform -- by Jan. 1, 1996. Methyl chloroform and other Class 1 substances may be used after the dead-line if sources can be found through recycling or existing inventories. Methyl chloroform is listed as a hazardous air pollutant under CAA. It also is a SARA Title III, Sec. 313 compound with a reportable quantity of 1,000 pounds. OSHA and the American Conference of Government Industrial Hygienists have set 350 ppm as the time-weighted average airborne exposure level for methyl chloroform. NIOSH lists its immediately dangerous to life or health'' concentration as 1,000 parts per million. DOT identifies the substance as a hazardous material, Class 6.1 (poison).

  13. Acetone poisoning

    MedlinePlus

    ... JavaScript. Acetone is a chemical used in many household products. This article discusses poisoning from swallowing acetone-based ... A.M. Editorial team. Related MedlinePlus Health Topics Household Products Browse the Encyclopedia A.D.A.M., Inc. ...

  14. Noteworthy Chemistry of Chloroform.

    PubMed

    Alston, Theodore A

    2016-07-01

    Inhaled chloroform anesthesia was introduced in 1847. Soon thereafter, the chemical reactivity of aerobically heated chloroform permitted John Snow and Claude Bernard to do seminal experiments in the assay of drug levels and drug metabolism. However, it was not widely appreciated until a clinical mishap in 1899 that thermal decomposition generated significant levels of toxic phosgene from air-polluting quantities of chloroform in poorly ventilated operating rooms that were illuminated by flames. Phosgene is also generated metabolically from chloroform. A clue appeared in the 1950s when subanesthetic traces of inhaled chloroform proved accidentally lethal to strains of male mice spontaneously expressing high levels of chloroform-metabolizing enzymes. Furthermore, in microbial experiments of 1967, the reactive chloroform molecule was inadvertently discovered to selectively inactivate vitamin B12-dependent enzymes. Chloroform can also activate enzymes. As a solvent, it was serendipitously found in 1903 to activate what is now known as plasminogen to plasmin. PMID:27480474

  15. Chloroform in the endodontic operatory

    SciTech Connect

    McDonald, M.N.; Vire, D.E. )

    1992-06-01

    This article reviews the role chloroform has played in dentistry and describes an occupational health clinical investigation into the possible hazards of chloroform use in the operatory. Due to a Food and Drug Administration ban on drugs and cosmetics containing chloroform, there has been some confusion as to whether the use of chloroform in the practice of dentistry is considered unsafe or has been prohibited. Utilizing common endodontic treatment methods employing chloroform, this study reports no negative health effects to the dentist or assistant and air vapor levels well below Occupational Health and Safety Administration mandated maximum levels. The report concludes that, with careful and controlled use, chloroform can be a useful adjunct in the practice of dentistry. The Food and Drug Administration has no jurisdiction over a dentist's use of chloroform in clinical practice and has not proven that chloroform is a human carcinogen.

  16. CANCER RISK ASSESSMENT FOR CHLOROFORM

    EPA Science Inventory

    Chloroform is a common chlorination by-product in drinking water. EPA has regulated chloroform as a probable human carcinogen under the Safe Drinking Water Act. The cancer risk estimate via ingestion was based on the 1985 Jorgenson study identifying kidney tumors in male Osborne ...

  17. Methyl chloroform and the atmosphere

    SciTech Connect

    Ravishankara, A.R.; Albritton, D.L.

    1995-07-14

    The atmospheric abundance of methyl chloroform, CH{sub 3}CCl{sub 3}, a compound of only anthropogenic origin, is actually decreasing because of emission reductions in compliance with the United Nations Montreal Protocol and its subsequent amendments. This observation, reported by Prinn and co-workers elsewhere in this issue, is based on data from surface-level monitoring stations. The observed trends in methyl chloroform abundance have a few straightforward scientific consequences and substantial policy relevance as discussed in this article. 6 refs., 1 fig.

  18. Optical sensors for the detection of trace chloroform.

    PubMed

    Fong, Jonathan K; Pena, Justin K; Xue, Zi-Ling; Alam, Maksudul M; Sampathkumaran, Uma; Goswami, Kisholoy

    2015-02-01

    Optical thin film sensors have been developed to detect chloroform in aqueous and nonaqueous solutions. These sensors utilize a modified Fujiwara reaction, one of the only known methods for detecting halogenated hydrocarbons in the visible spectrum. The modified Fujiwara reagents, 2,2'-dipyridyl and tetra-n-butyl ammonium hydroxide (n-Bu4NOH or TBAH), are encapsulated in an ethyl cellulose (EC) or sol-gel film. Upon exposure of the EC sensor film to HCCl3 in petroleum ether, a colored product is produced within the film, which is analyzed spectroscopically, yielding a detection limit of 0.830 ppm (parts per million v/v or μL/L hereinafter) and a quantification limit of 2.77 ppm. When the chloroform concentration in pentane is ≥5 ppm, the color change of the EC sensor is visible to the naked eye. In aqueous chloroform solution, reaction in the sol-gel sensor film turns the sensor from colorless to dark yellow/brown, also visible to the naked eye, with a detection limit of 500 ppm. This is well below the solubility of chloroform in water (ca. 5,800 ppm). To our knowledge, these are the first optical quality thin film sensors using Fujiwara reactions for halogenated hydrocarbon detection. PMID:25549694

  19. Icosapent Ethyl

    MedlinePlus

    ... weight loss, exercise) to reduce the amount of triglycerides (a fat-like substance) in your blood. Icosapent ... ethyl may work by decreasing the amount of triglycerides and other fats made in the liver.

  20. Ethyl carbamate

    Integrated Risk Information System (IRIS)

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

  1. Ethyl chloride

    Integrated Risk Information System (IRIS)

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

  2. Ethyl ether

    Integrated Risk Information System (IRIS)

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

  3. Ethyl acetate

    Integrated Risk Information System (IRIS)

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

  4. 27 CFR 21.103 - Chloroform.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Chloroform. 21.103 Section 21.103 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF... Chloroform. (a) Odor. Characteristic odor. (b) Specific gravity at 25 °/25 °C. Not less than 1.400....

  5. 27 CFR 21.103 - Chloroform.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Chloroform. 21.103 Section 21.103 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.103 Chloroform. (a) Odor. Characteristic odor....

  6. 27 CFR 21.103 - Chloroform.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Chloroform. 21.103 Section 21.103 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.103 Chloroform. (a) Odor. Characteristic odor....

  7. 27 CFR 21.103 - Chloroform.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Chloroform. 21.103 Section 21.103 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.103 Chloroform. (a) Odor. Characteristic odor....

  8. 27 CFR 21.103 - Chloroform.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Chloroform. 21.103 Section 21.103 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.103 Chloroform. (a) Odor. Characteristic odor....

  9. Activity Coefficients of Acetone-Chloroform Solutions: An Undergraduate Experiment. Undergraduate Experiment.

    ERIC Educational Resources Information Center

    Ozog, J. Z.; Morrison, J. A.

    1983-01-01

    Presents information, laboratory procedures, and results of an undergraduate experiment in which activity coefficients for a two-component liquid-vapor system are determined. Working in pairs, students can perform the experiment with 10 solutions in a given three-hour laboratory period. (Author/JN)

  10. Bacterial Cellular Materials as Precursors of Chloroform

    NASA Astrophysics Data System (ADS)

    Wang, J.; Ng, T.; Zhang, Q.; Chow, A. T.; Wong, P.

    2011-12-01

    The environmental sources of chloroform and other halocarbons have been intensively investigated because their effects of stratospheric ozone destruction and environmental toxicity. It has been demonstrated that microorganisms could facilitate the biotic generation of chloroform from natural organic matters in soil, but whether the cellular materials itself also serves as an important precursor due to photo-disinfection is poorly known. Herein, seven common pure bacterial cultures (Acinetobacter junii, Aeromonas hydrophila, Bacillus cereus, Bacillus substilis, Escherichia coli, Shigella sonnei, Staphylococcus sciuri) were chlorinated to evaluate the yields of chloroform, dibromochloromethane, dichlorobromomethane, and bromoform. The effects of bromide on these chemical productions and speciations were also investigated. Results showed that, on average, 5.64-36.42 μg-chloroform /mg-C were generated during the bacterial chlorination, in similar order of magnitude to that generated by humic acid (previously reported as 78 μg-chloroform/mg-C). However, unlike humic acid in water chlorination, chloroform concentration did not simply increase with the total organic carbon in water mixture. In the presence of bromide, the yield of brominated species responded linearly to the bromide concentration. This study provides useful information to understand the contributions of chloroform from photodisinfection processes in coastal environments.

  11. Homicide facilitated by inhalation of chloroform.

    PubMed

    Nashelsky, M B; Dix, J D; Adelstein, E H

    1995-01-01

    Three related homicides in which each decedent had significant concentrations of chloroform in blood, fat, brain and/or liver are described. The tissue concentrations of chloroform in one of three decedents were within reported lethal ranges. The concentrations in the remaining two decedents were less than lethal but were well above blood levels in nonoccupationally exposed, healthy subjects. The cause of death in one decedent with sublethal chloroform concentrations was suffocation; the cause of death in the other decedent could not be determined with certainty. The manner of death in each case was homicide. Through a review of the literature the authors discuss the history of chloroform as an inhalation anesthetic and the history of chloroform as an agent of abuse, suicide, assault, and homicide. Blood and/or tissue concentrations of chloroform in nonoccupationally exposed, healthy subjects and victims of suicide or homicide from previous reports are compared and contrasted with the amounts in blood and/or tissue in the three subjects described in this study. The authors conclude that, in addition to a direct lethal effect, chloroform may be used to incapacitate a victim of assault who then dies by another cause. PMID:7876797

  12. Analysis of phenolic acids as chloroformate derivatives using solid phase microextraction-gas chromatography.

    PubMed

    Citová, Ivana; Sladkovský, Radek; Solich, Petr

    2006-07-28

    In the presented study, a simple and original procedure of phenolic acids derivatization treated by ethyl and methyl chloroformate performed in an aqueous media consisting of acetonitrile, water, methanol/ethanol and pyridine has been modified and optimized. Seven phenolic acid standards-caffeic, ferulic, gallic, p-coumaric, protocatechuic, syringic and vanillic were derivatized into corresponding methyl/ethyl esters and subsequently determined by the means of gas chromatography connected to the flame-ionisation detector (FID). Some selected validation parameters as linearity, detection and quantitation limits and peak area repeatability were valued. The total time of gas chromatography (GC) analysis was 24 min for methyl chloroformate and 30 min for ethyl chloroformate derivatization. The more suitable methyl chloroformate derivatization was used for further experiments on the possibility of multiple pre-concentration by the direct solid phase microextraction technique (SPME). For this purpose, polyacrylate (PA), polydimethylsiloxane (PDMS), carboxen/polydimethylsiloxane (CAR/PDMS) and polydimethylsiloxane/divinylbenzene (PDMS/DVB) fibres were tested and the extraction conditions concerning time of extraction, temperature and time of desorption were optimized. The most polar PA fibre gave the best results under optimal extraction conditions (50 min extraction time, 25 degrees C extraction temperature and 10 min desorption time). As a result, the total time of SPME-GC analysis was 74 min and an increase in method sensitivity was reached. The limits of quantitation (LOQ) of p-coumaric, ferulic, syringic and vanillic acid esters after SPME pre-concentration were 0.02, 0.17, 0.2 and 0.2 microg mL(-1), respectively, showing approximately 10 times higher sensitivity in comparison with the original GC method. PMID:17723529

  13. 21 CFR 173.210 - Acetone.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Acetone. 173.210 Section 173.210 Food and Drugs..., Lubricants, Release Agents and Related Substances § 173.210 Acetone. A tolerance of 30 parts per million is established for acetone in spice oleoresins when present therein as a residue from the extraction of spice....

  14. 21 CFR 173.210 - Acetone.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Acetone. 173.210 Section 173.210 Food and Drugs..., Lubricants, Release Agents and Related Substances § 173.210 Acetone. A tolerance of 30 parts per million is established for acetone in spice oleoresins when present therein as a residue from the extraction of spice....

  15. Vibrational Excitation of Both Products of the Reaction of CN Radicals with Acetone in Solution

    PubMed Central

    2015-01-01

    Transient electronic and vibrational absorption spectroscopy unravel the mechanisms and dynamics of bimolecular reactions of CN radicals with acetone in deuterated chloroform solutions. The CN radicals are produced by ultrafast ultraviolet photolysis of dissolved ICN. Two reactive forms of CN radicals are distinguished by their electronic absorption bands: “free” (uncomplexed) CN radicals, and “solvated” CN radicals that are complexed with solvent molecules. The lifetimes of the free CN radicals are limited to a few picoseconds following their photolytic production because of geminate recombination to ICN and INC, complexation with CDCl3 molecules, and reaction with acetone. The acetone reaction occurs with a rate coefficient of (8.0 ± 0.5) × 1010 M–1 s–1 and transient vibrational spectra in the C=N and C=O stretching regions reveal that both the nascent HCN and 2-oxopropyl (CH3C(O)CH2) radical products are vibrationally excited. The rate coefficient for the reaction of solvated CN with acetone is 40 times slower than for free CN, with a rate coefficient of (2.0 ± 0.9) × 109 M–1 s–1 obtained from the rise in the HCN product v1(C=N stretch) IR absorption band. Evidence is also presented for CN complexes with acetone that are more strongly bound than the CN–CDCl3 complexes because of CN interactions with the carbonyl group. The rates of reactions of these more strongly associated radicals are slower still. PMID:26192334

  16. Vibrational Excitation of Both Products of the Reaction of CN Radicals with Acetone in Solution.

    PubMed

    Dunning, Greg T; Preston, Thomas J; Greaves, Stuart J; Greetham, Gregory M; Clark, Ian P; Orr-Ewing, Andrew J

    2015-12-17

    Transient electronic and vibrational absorption spectroscopy unravel the mechanisms and dynamics of bimolecular reactions of CN radicals with acetone in deuterated chloroform solutions. The CN radicals are produced by ultrafast ultraviolet photolysis of dissolved ICN. Two reactive forms of CN radicals are distinguished by their electronic absorption bands: "free" (uncomplexed) CN radicals, and "solvated" CN radicals that are complexed with solvent molecules. The lifetimes of the free CN radicals are limited to a few picoseconds following their photolytic production because of geminate recombination to ICN and INC, complexation with CDCl3 molecules, and reaction with acetone. The acetone reaction occurs with a rate coefficient of (8.0 ± 0.5) × 10(10) M(-1) s(-1) and transient vibrational spectra in the C═N and C═O stretching regions reveal that both the nascent HCN and 2-oxopropyl (CH3C(O)CH2) radical products are vibrationally excited. The rate coefficient for the reaction of solvated CN with acetone is 40 times slower than for free CN, with a rate coefficient of (2.0 ± 0.9) × 10(9) M(-1) s(-1) obtained from the rise in the HCN product v1(C═N stretch) IR absorption band. Evidence is also presented for CN complexes with acetone that are more strongly bound than the CN-CDCl3 complexes because of CN interactions with the carbonyl group. The rates of reactions of these more strongly associated radicals are slower still. PMID:26192334

  17. REVIEW OF THE MUTAGENICITY OF CHLOROFORM

    EPA Science Inventory

    Although chloroform (CHCl3) is metabolized in vivo and in vitro to a substance that covalently interacts with protein and lipid, its potential for binding to DNA is low. In addition, most of the assays for genotoxicity are negative. However, many of the genotoxicity results are i...

  18. [Admiral Isoroku Yamamoto and Chloroform Anesthesia].

    PubMed

    Matsuki, Akitomo

    2016-01-01

    Isoroku Yamamoto (1884-1943) who was on the Nisshin, an armored cruiser, received injuries to the left hand and right calf on May 27, 1905, at the Battle of Tsushima during the Russo-Japanese War. Three days later, he was admitted to the Sasebo Naval Hospital to undergo emergency amputations of the index and middle fingers of the left hand under chloroform anesthesia. He was, then, evacuated to the Yokosuka Naval Hospital, one of the naval background hospitals, and approximately, a month later, he received a muscle grafting taken from the left gluteal region. The procedure was most likely performed under chloroform anesthesia because chloroform was the only general anesthetic that the hospitals prepared. This grafting was not described in most of his biographies. In December 1916, he suffered from acute appendicitis and he was brought to the University of Tokyo Hospital, where an appendectomy was undertaken by Professor Tsugushige Kondo using chloroform ansthesia because Kondo had a great dislike for spinal anesthesia. PMID:27004395

  19. 21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Ethyl alcohol containing ethyl acetate. The feed additive ethyl alcohol containing ethyl acetate meets the requirement of 27 CFR 21.62, being not less than 92.5 percent ethyl alcohol, each 100 gallons... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Ethyl alcohol containing ethyl acetate....

  20. 21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Ethyl alcohol containing ethyl acetate. The feed additive ethyl alcohol containing ethyl acetate meets the requirement of 27 CFR 21.62, being not less than 92.5 percent ethyl alcohol, each 100 gallons... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Ethyl alcohol containing ethyl acetate....

  1. 21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Ethyl alcohol containing ethyl acetate. The feed additive ethyl alcohol containing ethyl acetate meets the requirement of 27 CFR 21.62, being not less than 92.5 percent ethyl alcohol, each 100 gallons... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Ethyl alcohol containing ethyl acetate....

  2. 21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Ethyl alcohol containing ethyl acetate. The feed additive ethyl alcohol containing ethyl acetate meets the requirement of 27 CFR 21.62, being not less than 92.5 percent ethyl alcohol, each 100 gallons... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ethyl alcohol containing ethyl acetate....

  3. 21 CFR 584.200 - Ethyl alcohol containing ethyl acetate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Ethyl alcohol containing ethyl acetate. The feed additive ethyl alcohol containing ethyl acetate meets the requirement of 27 CFR 21.62, being not less than 92.5 percent ethyl alcohol, each 100 gallons... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ethyl alcohol containing ethyl acetate....

  4. [Degradation of thiometon in ethyl acetate].

    PubMed

    Satoh, M; Shimokawa, S; Kobata, M; Tanaka, T; Nakanishi, Y

    2001-04-01

    When performing multiresidue analysis of pesticides, the recovery of thiometon was less than 20% from carrots and eggplants, but about 100% from garlic chives and welsh onions. The recovery of thiometon was found to depend on the lot of ethyl acetate. A 2-year-old lot of ethyl acetate caused degradation of thiometon, but a fresh lot of ethyl acetate did not. Analysis showed that ethyl acetate stored for 2 years contained about 5 microL/mL of acetaldehyde. Thiometon was also degraded by acetone or acetonitrile, when acetaldehyde was added to them, in the same manner as by aged ethyl acetate. The fact that the recovery of thiometon from welsh onions was about 100% indicated that some of the mercaptans in allium vegetables may prevent thiometon degradation. Mercaptans such as L-cysteine and 3-mercaptoproionic acid were confirmed to prevent the degradation of thiometon and disulfoton. These findings show that mercaptans may be useful additives for analyzing thiometon and disulfoton. PMID:11486375

  5. Ethyl Radical Ejection During Photodecomposition of Butanone on TiO2(110)

    SciTech Connect

    Henderson, Michael A.

    2008-10-15

    The photodecomposition of acetone and butanone were examined on the (110) surface of rutile TiO2 using temperature programmed desorption (TPD) and photon stimulated desorption (PSD). In both cases, photodecomposition was proceeded by a required thermal reaction between the adsorbed ketone and coadsorbed oxygen resulting in a diolate species. The diolate photodecomposed by ejection of an organic radical from the surface leaving behind a carboxylate species. In the acetone case, only methyl radical PSD was detected and acetate was left on the surface. In the butanone case there was a possibility of either methyl or ethyl radical ejection, with propionate or acetate left behind, respectively. However, only ethyl radical PSD was detected and the species left on the surface (acetate) was the same as in the acetone case. The preference for ethyl radical ejection is linked to the greater thermal stability of the ethyl radical over that of the methyl radical. Unlike in the acetone case, where the ejected methyl radicals did not participate in thermal chemistry on the TiO2(110) surface after photoactivation of the acetone diolate, ethyl radicals photodesorbing at 100 K from butanone diolate showed a preference for dehydrogenation to ethene through the influence of coadsorbed oxygen. These results reemphasize the mechanistic importance of organic radical production during photooxidation reactions on TiO2 surface. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

  6. Ethyl Radical Ejection During Photodecomposition of Butanone on TiO2(110)

    SciTech Connect

    Henderson, Michael A.

    2008-10-15

    The photodecomposition of acetone and butanone were examined on the (110) surface of rutile TiO2 using temperature programmed desorption (TPD) and photon stimulated desorption (PSD). In both cases, photodecomposition was proceeded by a required thermal reaction between the adsorbed ketone and coadsorbed oxygen resulting in a diolate species. The diolate photodecomposed by ejection of an organic radical from the surface leaving behind a carboxylate species. In the acetone case, only methyl radical PSD was detected and acetate was left on the surface. In the butanone case there was a possibility of either methyl or ethyl radical ejection, with propionate or acetate left behind, respectively. However, only ethyl radical PSD was detected and the species left on the surface (acetate) was the same as in the acetone case. The preference for ethyl radical ejection is linked to the greater thermal stability of the ethyl radical over that of the methyl radical. Unlike in the acetone case, where the ejected methyl radicals did not participate in thermal chemistry on the TiO2(110) surface after photoactivation of the acetone diolate, ethyl radicals photodesorbing at 100 K from butanone diolate showed a preference for dehydrogenation to ethene through the influence of coadsorbed oxygen. These results reemphasize the mechanistic importance of organic radical production during photooxidation reactions on TiO2 surface.

  7. Composition measurement of bicomponent droplets using laser-induced fluorescence of acetone

    NASA Astrophysics Data System (ADS)

    Maqua, C.; Depredurand, V.; Castanet, G.; Wolff, M.; Lemoine, F.

    2007-12-01

    Commercial fuels are complex mixtures, the evaporation of which remains particularly difficult to model. Experimental characterization of the differential vaporization of the components is a problem that is seldom addressed. In this paper, the evaporation of binary droplets made of ethyl-alcohol and acetone is investigated using a technique of measurement of the droplet composition developed in purpose. This technique exploits the laser induced fluorescence of acetone which acts as a fluorescent tracer as well as the more volatile component of the fuel associated with an accurate measurement of the droplet diameter by forward scattering interferometry. A model of the fluorescence intensity of the binary mixture, taking into account the absorption of the acetone molecules, is proposed and validated. The sensitivity of the technique is discussed. Finally, the reliability of the technique is demonstrated on binary combusting droplets in linear stream.

  8. Agglomeration and Sedimentation of MWCNTS in Chloroform

    NASA Astrophysics Data System (ADS)

    Eremin, Yu. S.; Kolesnikova, A. A.; Grekhov, A. M.

    The kinetics of agglomeration of multiwalled carbon nanotubes dispersed in chloroform has been studied by the methods of optical spectroscopy and dynamic light scattering. With the use of the models of the diffusion of cylindrical particles, the sizes of particles obtained by this method can be recalculated to the DLS data and the concentration at which the dispersion of individual МWCNTs occurs can be determined.

  9. Subchronic chloroform priming protects mice from a subsequently administered lethal dose of chloroform

    SciTech Connect

    Philip, Binu K.; Anand, Sathanandam S.; Palkar, Prajakta S.; Mumtaz, Moiz M.; Latendresse, John R.; Mehendale, Harihara M. . E-mail: mehendale@ulm.edu

    2006-10-01

    Protection offered by pre-exposure priming with a small dose of a toxicant against the toxic and lethal effects of a subsequently administered high dose of the same toxicant is autoprotection. Although autoprotection has been extensively studied with diverse toxicants in acute exposure regimen, not much is known about autoprotection after priming with repeated exposure. The objective of this study was to investigate this concept following repeated exposure to a common water contaminant, chloroform. Swiss Webster (SW) mice, exposed continuously to either vehicle (5% Emulphor, unprimed) or chloroform (150 mg/kg/day po, primed) for 30 days, were challenged with a normally lethal dose of chloroform (750 mg chloroform/kg po) 24 h after the last exposure. As expected, 90% of the unprimed mice died between 48 and 96 h after administration of the lethal dose in contrast to 100% survival of mice primed with chloroform. Time course studies indicated lower hepato- and nephrotoxicity in primed mice as compared to unprimed mice. Hepatic CYP2E1, glutathione levels (GSH), and covalent binding of {sup 14}C-chloroform-derived radiolabel did not differ between livers of unprimed and primed mice after lethal dose exposure, indicating that protection in liver is neither due to decreased bioactivation nor increased detoxification. Kidney GSH and glutathione reductase activity were upregulated, with a concomitant reduction in oxidized glutathione in the primed mice following lethal dose challenge, leading to decreased renal covalent binding of {sup 14}C-chloroform-derived radiolabel, in the absence of any change in CYP2E1 levels. Buthionine sulfoximine (BSO) intervention led to 70% mortality in primed mice challenged with lethal dose. These data suggest that higher detoxification may play a role in the lower initiation of kidney injury observed in primed mice. Exposure of primed mice to a lethal dose of chloroform led to 40% lower chloroform levels (AUC{sub 15-360min}) in the systemic

  10. Student Preparation of Acetone from 2-Propanol.

    ERIC Educational Resources Information Center

    Kauffman, J. M.; McKee, J. R.

    1982-01-01

    Background information, procedures, and materials needed are provided for an experiment in which acetone is produced from 2-propanol. The experiment does not use magnetic stirring, avoids the necessity for exhaustive extractions with ether, and produces a 60-percent yield of redistilled acetone within a two-and-one-half-hour laboratory period.…

  11. Chloroform induction of ornithine decarboxylase activity in rats.

    PubMed Central

    Savage, R E; Westrich, C; Guion, C; Pereira, M A

    1982-01-01

    Chloroform is a drinking water contaminant that has been demonstrated to be carcinogenic to mice and rats resulting in an increased incidence of liver and kidney tumors, respectively. The mechanism of chloroform carcinogenicity might be by tumor initiation and/or promotion. Since induction of ornithine decarboxylase (ODC) activity has been proposed as a molecular marker for tumor promoters, we have investigated the effect of chloroform on ODC activity in rats. Chloroform induced a dose-dependent increase of hepatic ODC with an apparent threshold at 100 mg/kg body weight. Female rats were two to four times more susceptible to to chloroform. Upon daily dosing of chloroform for 7 days the liver became less susceptible, with the last dose of chloroform resulting in only 10% of the activity observed after a single dose. Nuclear RNA polymerase I activity was also induced by chloroform. Chloroform, rather than increasing the activity of renal ODC, resulted in a 35% reduction. The induction by chloroform of hepatic ODC activity might be associated with regenerative hyperplasia while the renal carcinogenicity of chloroform could not be demonstrated to be associated with ODC induction. PMID:7151757

  12. Ethyl radical ejection during photodecomposition of butanone on TiO 2(1 1 0)

    NASA Astrophysics Data System (ADS)

    Henderson, Michael A.

    2008-10-01

    The photodecomposition of acetone and butanone were examined on the (1 1 0) surface of rutile TiO 2 using temperature programmed desorption (TPD) and photon stimulated desorption (PSD). In both cases, photodecomposition was preceded by a required thermal reaction between the adsorbed ketone and coadsorbed oxygen resulting in an adsorbed diolate species. The diolate photodecomposed by ejection of an organic radical from the surface leaving behind a carboxylate species. In the acetone case, only methyl radical PSD was detected and acetate was left on the surface. In the butanone case there was a possibility of either methyl or ethyl radical ejection, with propionate or acetate left behind, respectively. However, only ethyl radical PSD was detected and the species left on the surface (acetate) was the same as in the acetone case. The preference for ethyl radical ejection is linked to the greater stability of the C-CH 3 bond in butanone over that of the C-C 2H 5 bond. Unlike in the acetone case, where the ejected methyl radicals did not participate in thermal chemistry on the TiO 2(1 1 0) surface after photoactivation of the acetone diolate, ethyl radicals photodesorbing at 100 K from butanone diolate showed preference for dehydrogenation to ethene on the surface through the influence of coadsorbed oxygen. These results reemphasize the mechanistic importance of organic radical production during photooxidation reactions on TiO 2 surface.

  13. Review of the mutagenicity of chloroform

    SciTech Connect

    Rosenthal, S.L.

    1987-01-01

    Although chloroform (CHCl/sub 3/) is metabolized in vivo and in vitro to a substance that covalently interacts with protein and lipid, its potential for binding to DNA is low. In addition, most of the assays for genotoxicity are negative. However, many of the genotoxicity results are inconclusive because of inadequacies in the experimental protocols. The types of genotoxicity tests this report is based on include bacterial, yeast, host-mediated, Drosophila sex-linked recessive lethal, mammalian cell mutagenicity, sperm head abnormality, cytogenetic, and DNA damage. On the basis of presently available information, no definitive conclusion on the mutagenic potential of CHCl/sub 3/ can be reached.

  14. Chloroform and dichloromethane biodegradation kinetics with methanol as primary substrate

    SciTech Connect

    Sharma, D.; Suidan, M.T.; Gupta, M.; Sayles, G.D.

    1996-12-31

    Chloroform and dichloromethane biodegradation was studied in a methanogenic environment with methanol as the primary substrate. The rate of chloroform degradation was studied in an anaerobic chemostat containing a mixed microbial culture. A constant concentration of 1.93 g/l of methanol was fed to the chemostat and the chloroform concentration was varied up to 16.74 {mu}M. Biochemical Methane Potential (BMP) tests were conducted in serum bottles to study the kinetics of chloroform and dichloromethane degradation. The maximum rate of chloroform degradation of 0.45 {mu}M/hr was seen at an initial chloroform concentration of 3.85 {mu}M. Chloroform was degraded even without methanol, but the presence of methanol greatly increased the rate of chloroform degradation. However, an increase in methanol concentration beyond 50 mg/l did not increase the rate of degradation of chloroform. Chloroform concentration higher than 6.7{mu}M inhibited the degradation of methanol. The maximum rate of dichloromethane degradation of 0.25 {mu}M/hr was observed corresponding to an initial dichloromethane concentration of 3.34 {mu}M. Methanol was not inhibited even at high concentrations of dichloromethane.

  15. Chloroform-induced insanity defence confounds lawyer Lincoln.

    PubMed

    Spiegel, A D; Suskind, P B

    1997-12-01

    During an 1857 trial, the defence claimed that the accused should be absolved of wilful murder because an overdose of chloroform during surgery induced insanity. In a rare appearance as a prosecutor, Abraham Lincoln tried the case for the State of Illinois. Expert medical witnesses testified about the side effects of chloroform and chloroform-induced insanity. Significantly, Lincoln was not knowledgeable about medical jurisprudence and overlooked potential sources of evidence and expert witnesses. Defence lawyers presented an impressive array of physicians to testify about insanity, about chloroform and about the results of an overdosage during anaesthesia. Considering the state of scientific knowledge at the time, the trial was notable. PMID:11619819

  16. Determination of conformational and spectroscopic features of ethyl trans-alfa-cyano-3-indole-acrylate compound: An experimental and quantum chemical study

    NASA Astrophysics Data System (ADS)

    Cinar, Mehmet; Karabacak, Mehmet

    2013-03-01

    The optimized geometrical structure, vibrational and electronic transitions, chemical shifts and non-linear optical properties of ethyl trans-alfa-cyano-3-indole-acrylate (C14H12N2O2) compound were presented in this study. The ground state geometrical structure and vibrational wavenumbers were carried out by using density functional (DFT/B3LYP) method with 6-311++G(d,p) as basis set. The vibrational spectra of title compound were recorded in solid state with FT-IR and FT-Raman in the range of 4000-400 cm-1 and 4000-10 cm-1, respectively. The fundamental assignments were done on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. The 1H, 13C and DEPT NMR spectra were recorded in DMSO solution, and gauge-invariant atomic orbitals (GIAO) method was used to predict the isotropic chemical shifts. The UV-Vis absorption spectra of the compound were recorded in the range of 200-800 nm in various solvents of different polarity (acetone, benzene, chlorobenzene, chloroform, DMSO, ethanol, methanol and toluene). Solvent effects were calculated using TD-DFT and CIS method. To investigate the non-linear optical properties, the polarizability, anisotropy of polarizability and molecular first hyperpolarizability were computed. A detailed description of spectroscopic behaviors of compound was given based on the comparison of experimental measurements and theoretical computations.

  17. Determination of conformational and spectroscopic features of ethyl trans-alfa-cyano-3-indole-acrylate compound: an experimental and quantum chemical study.

    PubMed

    Cinar, Mehmet; Karabacak, Mehmet

    2013-03-01

    The optimized geometrical structure, vibrational and electronic transitions, chemical shifts and non-linear optical properties of ethyl trans-alfa-cyano-3-indole-acrylate (C(14)H(12)N(2)O(2)) compound were presented in this study. The ground state geometrical structure and vibrational wavenumbers were carried out by using density functional (DFT/B3LYP) method with 6-311++G(d,p) as basis set. The vibrational spectra of title compound were recorded in solid state with FT-IR and FT-Raman in the range of 4000-400 cm(-1) and 4000-10 cm(-1), respectively. The fundamental assignments were done on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. The (1)H, (13)C and DEPT NMR spectra were recorded in DMSO solution, and gauge-invariant atomic orbitals (GIAO) method was used to predict the isotropic chemical shifts. The UV-Vis absorption spectra of the compound were recorded in the range of 200-800 nm in various solvents of different polarity (acetone, benzene, chlorobenzene, chloroform, DMSO, ethanol, methanol and toluene). Solvent effects were calculated using TD-DFT and CIS method. To investigate the non-linear optical properties, the polarizability, anisotropy of polarizability and molecular first hyperpolarizability were computed. A detailed description of spectroscopic behaviors of compound was given based on the comparison of experimental measurements and theoretical computations. PMID:23274474

  18. Removal of chloroform from biodegradable therapeutic microspheres by radiolysis.

    PubMed

    Zielhuis, S W; Nijsen, J F W; Dorland, L; Krijger, G C; van Het Schip, A D; Hennink, W E

    2006-06-01

    Radioactive holmium-166 loaded poly(l-lactic acid) microspheres are promising systems for the treatment of liver malignancies. These microspheres are loaded with holmium acetylacetonate (HoAcAc) and prepared by a solvent evaporation method using chloroform. After preparation the microspheres (Ho-PLLA-MS) are activated by neutron irradiation in a nuclear reactor. It was observed that relatively large amounts of residual chloroform (1000-6000 ppm) remained in the microspheres before neutron irradiation. Since it is known that chloroform is susceptible for high-energy radiation, we investigated whether neutron and gamma irradiation could result in the removal of residual chloroform in HoAcAc-loaded and placebo PLLA-MS by radiolysis. To investigate this, microspheres with relatively high and low amounts of residual chloroform were subjected to irradiation. The effect of irradiation on the residual chloroform levels as well as other microsphere characteristics (morphology, size, crystallinity, molecular weight of PLLA and degradation products) were evaluated. No chloroform in the microspheres could be detected after neutron irradiation. This was also seen for gamma irradiation at a dose of 200 kGy phosgene, which can be formed as the result of radiolysis of chloroform, was not detected with gas chromatography-mass spectrometry (GC-MS). A precipitation titration showed that radiolysis of chloroform resulted in the formation of chloride. Gel permeation chromatography and differential scanning calorimetry showed a decrease in molecular weight of PLLA and crystallinity, respectively. However, no differences were observed between irradiated microsphere samples with high and low initial amounts of chloroform. In conclusion, this study demonstrates that neutron and gamma irradiation results in the removal of residual chloroform in PLLA-microspheres. PMID:16549282

  19. CONTROLLED, SHORT-TERM DERMAL AND INHALATION EXPOSURE TO CHLOROFORM

    EPA Science Inventory

    Studies were conducted to determine the uptake by humans of chloroform as a result of controlled short-term dermal and inhalation exposures. The approach used continuous real-time breath analysis to determine exhaled-breath profiles and evaluate chloroform kinetics in the huma...

  20. CAUSES OF DEATH OF ANESTHESIOLOGISTS FROM THE CHLOROFORM ERA

    EPA Science Inventory

    The investigation was undertaken to determine if there were an excess of cancer deaths occurring in anesthesiologists who practiced in an era when chloroform was in use and to estimate the degree of chloroform usage during that era. Causes of death of anesthesiologists dying betw...

  1. IRIS Toxicological Review and Summary Documents for Chloroform (Final Report)

    EPA Science Inventory

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

  2. Vibrational-translational relaxation in liquid chloroform

    NASA Astrophysics Data System (ADS)

    Takagi, K.; Choi, P.-K.; Negishi, K.

    1981-01-01

    Ultrasonic measurements were made in liquid chloroform over the frequency range from 3 MHz to 5 GHz by means of three experimental techniques, pulse-echo overlap, high-resolution Bragg reflection, and Brillouin scattering. The observed velocity dispersion revealed two relaxation processes, one at 650 MHz and the other at 5.1 GHz at 20 °C. They are interpreted in terms of vibrational-translational relaxation. Quantitative analysis of specific heat shows the lowest (261 cm-1) and the second lowest (366 cm-1) fundamental vibrational modes should have a common relaxation time at 50 ps and the group of all above the third mode (667 cm-1) at 290 ps. The present results are combined with recent data obtained by Laubereau et al. with the picosecond spectroscopy technique; a diagram illustrating V-T and V-V energy transfer is presented. A brief comment is given also on V-T and V-V processes in dichloromethane.

  3. Bacterial degradation of acetone in an outdoor model stream

    USGS Publications Warehouse

    Rathbun, R.E.; Stephens, D.W.; Tai, D.Y.

    1993-01-01

    Diurnal variations of the acetone concentration in an outdoor model stream were measured with and without a nitrate supplement to determine if the nitrate supplement would stimulate bacterial degradation of the acetone. Acetone loss coefficients were computed from the diurnal data using a fitting procedure based on a Lagrangian particle model. The coefficients indicated that bacterial degradation of the acetone was occurring in the downstream part of the stream during the nitrate addition. However, the acetone concentrations stabilized at values considerably above the limit of detection for acetone determination, in contrast to laboratory respirometer studies where the acetone concentration decreased rapidly to less than the detection limit, once bacterial acclimation to the acetone had occurred. One possible explanation for the difference in behavior was the limited 6-hour residence time of the acetone in the model stream.

  4. Occupational allergic contact dermatitis from ethyl cyanoacrylate.

    PubMed

    Bruze, M; Björkner, B; Lepoittevin, J P

    1995-03-01

    Glues based on cyanoacrylates are widely used as contact adhesives for metal, glass, rubber, plastics and textiles, as well for biological materials, including binding tissues and sealing wounds in surgery. In this paper, an apprentice cobbler with an occupational allergic contact dermatitis from an ethyl cyanoacrylate glue, in which the major monomer was shown to be the sensitizer, is reported. Initial patch testing with the cyanoacrylate glue dissolved in acetone with the Finn Chamber (aluminium) technique yielded false-negative reactions. Positive test reactions were obtained with the same preparations using Van der Bend chambers. With petrolatum as vehicle for the glue, there was no difference between Finn Chamber technique and Van der Bend chamber technique. The role of aluminium in the false-negative reactions is discussed. PMID:7774187

  5. High-yield synthesis of bioactive ethyl cinnamate by enzymatic esterification of cinnamic acid.

    PubMed

    Wang, Yun; Zhang, Dong-Hao; Zhang, Jiang-Yan; Chen, Na; Zhi, Gao-Ying

    2016-01-01

    In this paper, Lipozyme TLIM-catalyzed synthesis of ethyl cinnamate through esterification of cinnamic acid with ethanol was studied. In order to increase the yield of ethyl cinnamate, several media, including acetone, isooctane, DMSO and solvent-free medium, were investigated in this reaction. The reaction showed a high yield by using isooctane as reaction medium, which was found to be much higher than the yields reported previously. Furthermore, several parameters such as shaking rate, water activity, reaction temperature, substrate molar ratio and enzyme loading had important influences on this reaction. For instance, when temperature increased from 10 to 50 °C, the initial reaction rate increased by 18 times and the yield of ethyl cinnamate increased by 6.2 times. Under the optimum conditions, lipase-catalyzed synthesis of ethyl cinnamate gave a maximum yield of 99%, which was of general interest for developing industrial processes for the preparation of ethyl cinnamate. PMID:26213020

  6. 21 CFR 173.210 - Acetone.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Acetone. 173.210 Section 173.210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) SECONDARY DIRECT FOOD ADDITIVES PERMITTED IN FOOD FOR HUMAN CONSUMPTION Solvents, Lubricants, Release Agents and...

  7. 21 CFR 172.802 - Acetone peroxides.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... proportions of higher polymers, manufactured by reaction of hydrogen peroxide and acetone. (b) The additive may be mixed with an edible carrier to give a concentration of: (1) 3 grams to 10 grams of hydrogen...; or (2) approximately 0.75 gram of hydrogen peroxide equivalent per 100 grams of the additive,...

  8. 21 CFR 172.802 - Acetone peroxides.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... acetone peroxide, with minor proportions of higher polymers, manufactured by reaction of hydrogen peroxide... grams to 10 grams of hydrogen peroxide equivalent per 100 grams of the additive, plus carrier, for use in flour maturing and bleaching; or (2) approximately 0.75 gram of hydrogen peroxide equivalent...

  9. 21 CFR 172.802 - Acetone peroxides.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... acetone peroxide, with minor proportions of higher polymers, manufactured by reaction of hydrogen peroxide... grams to 10 grams of hydrogen peroxide equivalent per 100 grams of the additive, plus carrier, for use in flour maturing and bleaching; or (2) approximately 0.75 gram of hydrogen peroxide equivalent...

  10. 21 CFR 172.802 - Acetone peroxides.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... acetone peroxide, with minor proportions of higher polymers, manufactured by reaction of hydrogen peroxide... grams to 10 grams of hydrogen peroxide equivalent per 100 grams of the additive, plus carrier, for use in flour maturing and bleaching; or (2) approximately 0.75 gram of hydrogen peroxide equivalent...

  11. 21 CFR 172.802 - Acetone peroxides.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... acetone peroxide, with minor proportions of higher polymers, manufactured by reaction of hydrogen peroxide... grams to 10 grams of hydrogen peroxide equivalent per 100 grams of the additive, plus carrier, for use in flour maturing and bleaching; or (2) approximately 0.75 gram of hydrogen peroxide equivalent...

  12. [Hygienic evaluation of the combined effect of portable water chloroform].

    PubMed

    Iksanova, T I; Malysheva, A G; Rastiannikov, E G; Egorova, I A; Krasovskiĭ, G N; Nikolaev, M G

    2006-01-01

    The paper considers the significance of complex entrance of chloroform from portable water into the human body (enterally, inhalationally, and through the intact skin). It shows it necessary to toughen the maximum permissible concentration (MPC) of chloroform in the portable drinking, by taking into account of the multiplicity of routes of its action on the population. The authors present the results of their own investigations of the levels of chloroform in the air of bath and shower rooms before and after taking a shower and filling the bath with water, as well as in the airspace layer above the water of an indoor swimming pool, by using chromatographic mass-spectrometry. PMID:16758810

  13. Human respiratory uptake of chloroform and haloketones during showering.

    PubMed

    Xu, Xu; Weisel, Clifford P

    2005-01-01

    Inhalation is an important exposure route for volatile water contaminants, including disinfection by-products (DBPs). A controlled human study was conducted on six subjects to determine the respiratory uptake of haloketones (HKs) and chloroform, a reference compound, during showering. Breath and air concentrations of the DBPs were measured using gas chromatography and electron capture detector during and following the inhalation exposures. A lower percentage of the HKs (10%) is released from shower water to air than that of chloroform (56%) under the experiment conditions due to the lower volatility of the HKs. Breath concentrations of the DBPs were elevated during the inhalation exposure, while breath concentrations decreased rapidly after the exposure. Approximately 85-90% of the inhaled HKs were absorbed, whereas only 70% of the inhaled chloroform was absorbed for the experiment conditions used. The respiratory uptake of the DBPs was estimated using a linear one-compartment model coupled with a plug flow stream model for the shower system. The internal dose of chloroform normalized to its water concentration was approximately four times that of the HKs after a 30-min inhalation exposure. Approximately 0.3-0.4% of the absorbed HKs and 2-9% of the absorbed chloroform were expired through lung excretion after the 30-min exposure. The inhalation exposure from a typical 10-15 min shower contributes significantly to the total dose for chloroform in chlorinated drinking water but only to a moderate extent for HKs. PMID:15138448

  14. Durability of organobentonite-amended liner for decelerating chloroform transport.

    PubMed

    He, Shichong; Zhu, Lizhong

    2016-04-01

    Chloroform is added to landfill for suppressing methane generation, which however may transport through landfill liners and lead to contamination of groundwater. To decelerate chloroform transport, the enhanced sorption ability of clay liners following organobentonite addition was tested. In this study, we used batch sorption to evaluate sorption capacity of chloroform to organobentonite, followed by column tests and model simulations for assessing durability of different liners. Results show that adding 10% CTMAB-bentonite (organobentonite synthesized using cetyltrimethylammonium bromide) increased the duration of a bentonite liner by 88.5%. CTMAB-bentonite consistently showed the highest sorption capacity (Qm) among six typical organobentonites under various environmental conditions. The removal rate of chloroform by CTMAB-bentonite was 3.6-23 times higher than that by natural soils. According to the results derived by model simulation, a 70-cm 10% CTMAB-bentonite liner exhibited much better durability than a 100-cm compact clay liner (CCL) and natural bentonite liner evidenced by the delayed and lower peak of eluent concentration. A minimum thickness of 65.8 cm of the 10% CTMAB-bentonite liner could completely sorb the chloroform in a 100-m-high landfill. The 10% CTMAB-bentonite liner exhibiting much better durability has the promise for reducing environmental risk of chloroform in landfill. PMID:26874063

  15. 46 CFR 153.1035 - Acetone cyanohydrin or lactonitrile solutions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Acetone cyanohydrin or lactonitrile solutions. 153.1035... Special Cargo Procedures § 153.1035 Acetone cyanohydrin or lactonitrile solutions. No person may operate a tankship carrying a cargo of acetone cyanohydrin or lactonitrile solutions, unless that cargo is...

  16. 46 CFR 153.1035 - Acetone cyanohydrin or lactonitrile solutions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Acetone cyanohydrin or lactonitrile solutions. 153.1035... Special Cargo Procedures § 153.1035 Acetone cyanohydrin or lactonitrile solutions. No person may operate a tankship carrying a cargo of acetone cyanohydrin or lactonitrile solutions, unless that cargo is...

  17. 46 CFR 153.1035 - Acetone cyanohydrin or lactonitrile solutions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Acetone cyanohydrin or lactonitrile solutions. 153.1035... Special Cargo Procedures § 153.1035 Acetone cyanohydrin or lactonitrile solutions. No person may operate a tankship carrying a cargo of acetone cyanohydrin or lactonitrile solutions, unless that cargo is...

  18. 46 CFR 153.1035 - Acetone cyanohydrin or lactonitrile solutions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Acetone cyanohydrin or lactonitrile solutions. 153.1035... Special Cargo Procedures § 153.1035 Acetone cyanohydrin or lactonitrile solutions. No person may operate a tankship carrying a cargo of acetone cyanohydrin or lactonitrile solutions, unless that cargo is...

  19. 46 CFR 153.1035 - Acetone cyanohydrin or lactonitrile solutions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Acetone cyanohydrin or lactonitrile solutions. 153.1035... Special Cargo Procedures § 153.1035 Acetone cyanohydrin or lactonitrile solutions. No person may operate a tankship carrying a cargo of acetone cyanohydrin or lactonitrile solutions, unless that cargo is...

  20. The BUME method: a novel automated chloroform-free 96-well total lipid extraction method for blood plasma[S

    PubMed Central

    Löfgren, Lars; Ståhlman, Marcus; Forsberg, Gun-Britt; Saarinen, Sinikka; Nilsson, Ralf; Hansson, Göran I.

    2012-01-01

    Lipid extraction from biological samples is a critical and often tedious preanalytical step in lipid research. Primarily on the basis of automation criteria, we have developed the BUME method, a novel chloroform-free total lipid extraction method for blood plasma compatible with standard 96-well robots. In only 60 min, 96 samples can be automatically extracted with lipid profiles of commonly analyzed lipid classes almost identically and with absolute recoveries similar or better to what is obtained using the chloroform-based reference method. Lipid recoveries were linear from 10–100 µl plasma for all investigated lipids using the developed extraction protocol. The BUME protocol includes an initial one-phase extraction of plasma into 300 µl butanol:methanol (BUME) mixture (3:1) followed by two-phase extraction into 300 µl heptane:ethyl acetate (3:1) using 300 µl 1% acetic acid as buffer. The lipids investigated included the most abundant plasma lipid classes (e.g., cholesterol ester, free cholesterol, triacylglycerol, phosphatidylcholine, and sphingomyelin) as well as less abundant but biologically important lipid classes, including ceramide, diacylglycerol, and lyso-phospholipids. This novel method has been successfully implemented in our laboratory and is now used daily. We conclude that the fully automated, high-throughput BUME method can replace chloroform-based methods, saving both human and environmental resources. PMID:22645248

  1. Promotion of dropwise condensation of ethyl alcohol, methyl alcohol, and acetone by polytetrafluoroethylene

    NASA Technical Reports Server (NTRS)

    Kirby, C. E.

    1972-01-01

    Coating condensing surfaces with thin layer of nonpolar Teflon results in dropwise condensation of polar organic vapor. Greater heat transfer coefficients are produced increasing effectiveness of condensing system. Investigation shows that vapors with strong dipole moment tend to condense dropwise.

  2. Chlorimuron-ethyl

    Integrated Risk Information System (IRIS)

    Chlorimuron - ethyl ; CASRN 90982 - 32 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinog

  3. Methyl ethyl ketone (MEK)

    Integrated Risk Information System (IRIS)

    Methyl ethyl ketone ( MEK ) ( CASRN 78 - 93 - 3 ) Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Nonc

  4. Ethyl alcohol production

    SciTech Connect

    Hofman, V.; Hauck, D.

    1980-11-01

    Recent price increases and temporary shortages of petroleum products have caused farmers to search for alternate sources of fuel. The production of ethyl alcohol from grain is described and the processes involved include saccharification, fermentation and distillation. The resulting stillage has potential as a livestock feed.

  5. Marine Vibrio Species Produce the Volatile Organic Compound Acetone

    PubMed Central

    Nemecek-Marshall, M.; Wojciechowski, C.; Kuzma, J.; Silver, G. M.; Fall, R.

    1995-01-01

    While screening aerobic, heterotrophic marine bacteria for production of volatile organic compounds, we found that a group of isolates produced substantial amounts of acetone. Acetone production was confirmed by gas chromatography, gas chromatography-mass spectrometry, and high-performance liquid chromatography. The major acetone producers were identified as nonclinical Vibrio species. Acetone production was maximal in the stationary phase of growth and was stimulated by addition of l-leucine but not the other common amino acids, suggesting that leucine degradation leads to acetone formation. Acetone production by marine vibrios may contribute to the dissolved organic carbon associated with phytoplankton, and some of the acetone produced may be volatilized to the atmosphere. PMID:16534920

  6. Chloroform: exposure estimation, hazard characterization, and exposure-response analysis.

    PubMed

    Meek, M E; Beauchamp, R; Long, G; Moir, D; Turner, L; Walker, M

    2002-01-01

    Chloroform has been assessed as a Priority Substance under the Canadian Environmental Protection Act. The general population in Canada is exposed to chloroform principally through inhalation of indoor air, particularly during showering, and through ingestion of tap water. Data on concentrations of chloroform in various media were sufficient to serve as the basis for development of deterministic and probabilistic estimates of exposure for the general population in Canada. On the basis of data acquired principally in studies in experimental animals, chloroform causes hepatic and renal tumors in mice and renal tumors in rats. The weight of evidence indicates that chloroform is likely carcinogenic only at concentrations that induce the obligatory precursor lesions of cytotoxicity and proliferative regenerative response. Since this cytotoxicity is primarily related to rates of formation of reactive, oxidative metabolites, dose response has been characterized in the context of rates of formation of reactive metabolites in the target tissue. Results presented here are from a "hybrid" physiologically based pharmacokinetic (PBPK) animal model that was revised to permit its extension to humans. The relevant measure of exposure response, namely, the mean rate of metabolism in humans associated with a 5% increase in tumor risk (TC05), was estimated on the basis of this PBPK model and compared with tissue dose measures resulting from 24-h multimedia exposure scenarios for Canadians based on midpoint and 95th percentiles for concentrations in outdoor air, indoor air, air in the shower compartment, air in the bathroom after showering, tap water, and food. Nonneoplastic effects observed most consistently at lowest concentrations or doses following repeated exposures of rats and mice to chloroform are cytotoxicity and regenerative proliferation. As for cancer, target organs are the liver and kidney. In addition, chloroform has induced nasal lesions in rats and mice exposed by both

  7. Chloroform alters interleaflet coupling in lipid bilayers: an entropic mechanism

    PubMed Central

    Reigada, Ramon; Sagués, Francesc

    2015-01-01

    The interaction of the two leaflets of the plasmatic cell membrane is conjectured to play an important role in many cell processes. Experimental and computational studies have investigated the mechanisms that modulate the interaction between the two membrane leaflets. Here, by means of coarse-grained molecular dynamics simulations, we show that the addition of a small and polar compound such as chloroform alters interleaflet coupling by promoting domain registration. This is interpreted in terms of an entropic gain that would favour frequent chloroform commuting between the two leaflets. The implication of this effect is discussed in relation to the general anaesthetic action. PMID:25833246

  8. Acetone-butanol Fermentation of Marine Macroalgae

    SciTech Connect

    Huesemann, Michael H.; Kuo, Li-Jung; Urquhart, Lindsay A.; Gill, Gary A.; Roesijadi, Guritno

    2012-03-01

    Mannitol and laminarin, which are present at high concentrations in the brown macroalga Saccharina spp., a type of kelp, are potential biochemical feedstocks for butanol production. To test their bioconversion potential, aqueous extracts of the kelp Saccharina spp., mannitol, and glucose (a product of laminarin hydrolysis) were subjected to acetone-butanol fermentation by Clostridium acetobutylicum (ATCC 824). Both mannitol and glucose were readily fermented. Mixed substrate fermentations with glucose and mannitol resulted in diauxic growth of C. acetobutylicum with glucose depletion preceding mannitol utilization. Fermentation of kelp extract exhibited triauxic growth, with an order of utilization of free glucose, mannitol, and bound glucose, presumably laminarin. The lag in laminarin utilization reflected the need for enzymatic hydrolysis of this polysaccharide into fermentable sugars. The butanol and total solvent yields were 0.12 g/g and 0.16 g/g, respectively, indicating that significant improvements are still needed to make industrial-scale acetone-butanol fermentations of seaweed economically feasible.

  9. Economic evaluation of the acetone - butanol fermentation

    SciTech Connect

    Lenz, T.G.; Morevra, A.R.

    1980-12-01

    The economics of producing acetone and 1-butanol via fermentation have been examined for a 45 X 10 to the power of 6 kg of solvents/year plant. For a molasses substrate, the total annual production costs were about $24.4 million vs. a total annual income of $36 million, with about $20 million total required capital. Molasses cost of about $24.4 million/year was critical to these economics. Liquid whey was next evaluated as an alternative feed. Whey feed saved about $11 million annually in feed costs and yielded about $7 million net additional annual revenues from protein sale. These primary differences gave an annual gross profit of about $15 million for the whey case and resulted in a discounted cash flow rate of return of 29%. It is concluded that waste based acetone-butanol production via fermentation deserves further attention in view of the attractive whey-based economics and the excellent potential of butanol as a fuel extender, especially for diesohol blending.

  10. Enzymology of acetone-butanol-isopropanol formation

    SciTech Connect

    Chen, Jiann-Shin.

    1992-01-01

    The long-term goal of the project is to understand the fundamental properties of biological solvent production. Our approach is to elucidate first the molecular properties of solvent-producing enzymes and then to apply to information gained from the enzymological study to investigate control mechanisms for the solvent-producing pathways and the expression of solvent-production genes. Our research primarily involves two strains of Clostridium beijerinckii: C. Beijerinckii NRRL B593 which produces isopropanol in addition to acetone, butanol, and ethanol, and C. beijerinckii NRRL B592 which produces acetone, butanol and ethanol, but not isopropanol. In more recent studies, we also included another solvent-producing organism, Bacillus macerans. Objectives for the reporting period were: to characterize the distinct types of alcohol dehydrogenase; to purify and characterize acetoacetyl-CoA-reacting enzymes; and to clone and sequence the gene encoding the primary/secondary alcohol dehydrogenase of C beijerinckii NRRL B593 and to search for the promoter region for solvent-production genes.

  11. Excellent acetone sensing properties of porous ZnO

    NASA Astrophysics Data System (ADS)

    Liu, Chang-Bai; Liu, Xing-Yi; Wang, Sheng-Lei

    2015-01-01

    Porous ZnO was obtained by hydrothermal method. The results of scanning electron microscope revealed the porous structure in the as-prepared materials. The acetone sensing test results of porous ZnO show that porous ZnO possesses excellent acetone gas sensing properties. The response is 35.5 at the optimum operating temperature of 320 °C to 100 ppm acetone. The response and recovery times to 50 ppm acetone are 2 s and 8 s, respectively. The lowest detecting limit to acetone is 0.25 ppm, and the response value is 3.8. Moreover, the sensors also exhibit excellent selectivity and long-time stability to acetone. Projected supported by the Project of Challenge Cup for College Students, China (Grant No. 450060497053).

  12. Apparatus and method for monitoring breath acetone and diabetic diagnostics

    DOEpatents

    Duan, Yixiang; Cao, Wenqing

    2008-08-26

    An apparatus and method for monitoring diabetes through breath acetone detection and quantitation employs a microplasma source in combination with a spectrometer. The microplasma source provides sufficient energy to produce excited acetone fragments from the breath gas that emit light. The emitted light is sent to the spectrometer, which generates an emission spectrum that is used to detect and quantify acetone in the breath gas.

  13. An unusual autoerotic fatality associated with chloroform inhalation.

    PubMed

    Singer, Peter P; Jones, Graham R

    2006-04-01

    We report the death of a young male attributed to chloroform poisoning during autoerotic asphyxia. He was found lying on the floor of his apartment, prone on a piece of foam and a towel. His eyes were bound with a towel, his lower face and nose were almost entirely covered with duct tape surrounding a rubber hose in his mouth. The other end of the hose was loosely sitting inside an open bottle which was in a box beside him. He was bound-up by an intricate system of ropes, handles, and rods, ending with a noose around his neck. Toxicology testing indicated chloroform concentrations of 18.1 mg/L in femoral blood and 1.5 mg/L in urine. Chloroform was measured by headspace gas chromatography with flame-ionization detection using 1,1,1-trichloroethane as the internal standard. The cause of death was recorded as "chloroform toxicity" with "autoerotic asphyxia" as a contributing factor, and the manner of death was "accidental". PMID:16803657

  14. BINDING OF CHLOROFORM TO THE CYSTEINE OF HEMOGLOBIN

    EPA Science Inventory

    The products of the covalent binding of chloroform to rat hemoglobin during microsomal metabolism were isolated and identified by gas chromatography (GC) and mass spectroscopy (MS). After isolation by Proteinase K hydrolysis, amino acid analysis and cellulose thin-layer chromatog...

  15. Stereoselective titanium-mediated aldol reactions of a chiral lactate-derived ethyl ketone with ketones.

    PubMed

    Alcoberro, Sandra; Gómez-Palomino, Alejandro; Solà, Ricard; Romea, Pedro; Urpí, Fèlix; Font-Bardia, Mercè

    2014-01-17

    Aldol reactions of titanium enolates of lactate-derived ethyl ketone 1 with other ketones proceed in a very efficient and stereocontrolled manner provided that a further equivalent of TiCl4 is added to the reacting mixture. The scope of these reactions encompasses simple ketones such as acetone or cyclohexanone as well as other ketones that contain potential chelating groups such as pyruvate esters or α- and β-hydroxy ketones. PMID:24372372

  16. Effect of water temperature on dermal exposure to chloroform.

    PubMed Central

    Gordon, S M; Wallace, L A; Callahan, P J; Kenny, D V; Brinkman, M C

    1998-01-01

    We have developed and applied a new measurement methodology to investigate dermal absorption of chloroform while bathing. Ten subjects bathed in chlorinated water while breathing pure air through a face mask. Their exhaled breath was delivered to a glow discharge source/ion trap mass spectrometer for continuous real-time measurement of chloroform in the breath. This new method provides abundant data compared to previous discrete time-integrated breath sampling methods. The method is particularly well suited to studying dermal exposure because the full face mask eliminates exposure to contaminated air. Seven of the 10 subjects bathed in water at two or three different temperatures between 30 degrees C and 40 degrees C. Subjects at the highest temperatures exhaled about 30 times more chloroform than the same subjects at the lowest temperatures. This probably results from a decline in blood flow to the skin at the lower temperatures as the body seeks to conserve heat forcing the chloroform to diffuse over a much greater path length before encountering the blood. These results suggest that pharmacokinetic models need to employ temperature-dependent parameters. Two existing models predict quite different times of about 12 min and 29 min for chloroform flux through the stratum corneum to reach equilibrium. At 40 degrees C, the time for the flux to reach a near steady-state value is 6-9 min. Although uptake and decay processes involve several body compartments, the complicating effect of the stratum corneum lag time made it difficult to fit multiexponential curves to the data; however, a single-compartment model gave a satisfactory fit. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:9618350

  17. Dissociative electron attachment studies on acetone

    SciTech Connect

    Prabhudesai, Vaibhav S. Tadsare, Vishvesh; Ghosh, Sanat; Gope, Krishnendu; Davis, Daly; Krishnakumar, E.

    2014-10-28

    Dissociative electron attachment (DEA) to acetone is studied in terms of the absolute cross section for various fragment channels in the electron energy range of 0–20 eV. H{sup −} is found to be the most dominant fragment followed by O{sup −} and OH{sup −} with only one resonance peak between 8 and 9 eV. The DEA dynamics is studied by measuring the angular distribution and kinetic energy distribution of fragment anions using Velocity Slice Imaging technique. The kinetic energy and angular distribution of H{sup −} and O{sup −} fragments suggest a many body break-up for the lone resonance observed. The ab initio calculations show that electron is captured in the multi-centered anti-bonding molecular orbital which would lead to a many body break-up of the resonance.

  18. Reduction of acetone to isopropanol using producer gas fermenting microbes.

    PubMed

    Ramachandriya, Karthikeyan D; Wilkins, Mark R; Delorme, Marthah J M; Zhu, Xiaoguang; Kundiyana, Dimple K; Atiyeh, Hasan K; Huhnke, Raymond L

    2011-10-01

    Gasification-fermentation is an emerging technology for the conversion of lignocellulosic materials into biofuels and specialty chemicals. For effective utilization of producer gas by fermenting bacteria, tar compounds produced in the gasification process are often removed by wet scrubbing techniques using acetone. In a preliminary study using biomass generated producer gas scrubbed with acetone, an accumulation of acetone and subsequent isopropanol production was observed. The effect of 2 g/L acetone concentrations in the fermentation media on growth and product distributions was studied with "Clostridium ragsdalei," also known as Clostridium strain P11 or P11, and Clostridium carboxidivorans P7 or P7. The reduction of acetone to isopropanol was possible with "C. ragsdalei," but not with P7. In P11 this reaction occurred rapidly when acetone was added in the acidogenic phase, but was 2.5 times slower when added in the solventogenic phase. Acetone at concentrations of 2 g/L did not affect the growth of P7, but ethanol increased by 41% and acetic acid concentrations decreased by 79%. In the fermentations using P11, growth was unaffected and ethanol concentrations increased by 55% when acetone was added in the acidogenic phase. Acetic acid concentrations increased by 19% in both the treatments where acetone was added. Our observations indicate that P11 has a secondary alcohol dehydrogenase that enables it to reduce acetone to isopropanol, while P7 lacks this enzyme. P11 offers an opportunity for biological production of isopropanol from acetone reduction in the presence of gaseous substrates (CO, CO₂, and H₂). PMID:21557204

  19. Biological hydrogen production using chloroform-treated methanogenic granules.

    PubMed

    Hu, Bo; Chen, Shulin

    2008-03-01

    In fermentative hydrogen production, the low-hydrogen-producing bacteria retention rate limits the suspended growth reactor productivity because of the long hydraulic retention time (HRT) required to maintain adequate bacteria population. Traditional bacteria immobilization methods such as calcium alginate entrapment have many application limitations in hydrogen fermentation, including limited duration time, bacteria leakage, cost, and so on. The use of chloroform-treated anaerobic granular sludge as immobilized hydrogen-producing bacteria in an immobilized hydrogen culture may be able to overcome the limitations of traditional immobilization methods. This paper reports the findings on the performance of fed-batch cultures and continuous cultures inoculated with chloroform-treated granules. The chloroform-treated granules were able to be reused over four fed-batch cultures, with pH adjustment. The upflow reactor packed with chloroform-treated granules was studied, and the HRT of the upflow reactor was found to be as low as 4 h without any decrease in hydrogen production yield. Initial pH and glucose concentration of the culture medium significantly influenced the performance of the reactor. The optimum initial pH of the culture medium was neutral, and the optimum glucose concentration of the culture medium was below 20 g chemical oxygen demand/L at HRT 4 h. This study also investigated the possibility of integrating immobilized hydrogen fermentation using chloroform-treated granules with immobilized methane production using untreated granular sludge. The results showed that the integrated batch cultures produced 1.01 mol hydrogen and 2 mol methane per mol glucose. Treating the methanogenic granules with chloroform and then using the treated granules as immobilized hydrogen-producing sludge demonstrated advantages over other immobilization methods because the treated granules provide hydrogen-producing bacteria with a protective niche, a long duration of an active

  20. Biological Hydrogen Production Using Chloroform-treated Methanogenic Granules

    NASA Astrophysics Data System (ADS)

    Hu, Bo; Chen, Shulin

    In fermentative hydrogen production, the low-hydrogen-producing bacteria retention rate limits the suspended growth reactor productivity because of the long hydraulic retention time (HRT) required to maintain adequate bacteria population. Traditional bacteria immobilization methods such as calcium alginate entrapment have many application limitations in hydrogen fermentation, including limited duration time, bacteria leakage, cost, and so on. The use of chloroform-treated anaerobic granular sludge as immobilized hydrogen-producing bacteria in an immobilized hydrogen culture may be able to overcome the limitations of traditional immobilization methods. This paper reports the findings on the performance of fed-batch cultures and continuous cultures inoculated with chloroform-treated granules. The chloroform-treated granules were able to be reused over four fed-batch cultures, with pH adjustment. The upflow reactor packed with chloroform-treated granules was studied, and the HRT of the upflow reactor was found to be as low as 4 h without any decrease in hydrogen production yield. Initial pH and glucose concentration of the culture medium significantly influenced the performance of the reactor. The optimum initial pH of the culture medium was neutral, and the optimum glucose concentration of the culture medium was below 20 g chemical oxygen demand/L at HRT 4 h. This study also investigated the possibility of integrating immobilized hydrogen fermentation using chloroform-treated granules with immobilized methane production using untreated granular sludge. The results showed that the integrated batch cultures produced 1.01 mol hydrogen and 2 mol methane per mol glucose. Treating the methanogenic granules with chloroform and then using the treated granules as immobilized hydrogen-producing sludge demonstrated advantages over other immobilization methods because the treated granules provide hydrogen-producing bacteria with a protective niche, a long duration of an active

  1. In situ hydrogen, acetone, butanol, ethanol and microdiesel production by Clostridium acetobutylicum ATCC 824 from oleaginous fungal biomass.

    PubMed

    Hassan, Elhagag Ahmed; Abd-Alla, Mohamed Hemida; Bagy, Magdy Mohamed Khalil; Morsy, Fatthy Mohamed

    2015-08-01

    An in situ batch fermentation technique was employed for biohydrogen, acetone, butanol, ethanol and microdiesel production from oleaginous fungal biomass using the anaerobic fermentative bacterium Clostridium acetobutylicum ATCC 824. Oleaginous fungal Cunninghamella echinulata biomass which has ability to accumulate up to 71% cellular lipid was used as the substrate carbon source. The maximum cumulative hydrogen by C. acetobutylicum ATCC 824 from crude C. echinulata biomass was 260 ml H2 l(-1), hydrogen production efficiency was 0.32 mol H2 mole(-1) glucose and the hydrogen production rate was 5.2 ml H2 h(-1). Subsequently, the produced acids (acetic and butyric acids) during acidogenesis phase are re-utilized by ABE-producing clostridia and converted into acetone, butanol, and ethanol. The total ABE produced by C. acetobutylicum ATCC 824 during batch fermentation was 3.6 g l(-1) from crude fungal biomass including acetone (1.05 g l(-1)), butanol (2.19 g l(-1)) and ethanol (0.36 g l(-1)). C. acetobutylicum ATCC 824 has ability to produce lipolytic enzymes with a specific activity 5.59 U/mg protein to hydrolyze ester containing substrates. The lipolytic potential of C. acetobutylicum ATCC 824 was used as a biocatalyst for a lipase transesterification process using the produced ethanol from ABE fermentation for microdiesel production. The fatty acid ethyl esters (microdiesel) generated from the lipase transesterification of crude C. echinulata dry mass was analyzed by GC/MS as 15.4% of total FAEEs. The gross energy content of biohydrogen, acetone, butanol, ethanol and biodiesel generated through C. acetobutylicum fermentation from crude C. echinulata dry mass was 3113.14 kJ mol(-1). These results suggest a possibility of integrating biohydrogen, acetone, butanol and ethanol production technology by C. acetobutylicum with microdiesel production from crude C. echinulata dry mass and therefore improve the feasibility and commercialization of bioenergy production. PMID

  2. Effect of Cobalt Particle Size on Acetone Steam Reforming

    SciTech Connect

    Sun, Junming; Zhang, He; Yu, Ning; Davidson, Stephen D.; Wang, Yong

    2015-06-11

    Carbon-supported cobalt nanoparticles with different particle sizes were synthesized and characterized by complementary characterization techniques such as X-ray diffraction, N-2 sorption, acetone temperature-programmed desorption, transmission electron microscopy, and CO chemisorption. Using acetone steam reforming reaction as a probe reaction, we revealed a volcano-shape curve of the intrinsic activity (turnover frequency of acetone) and the CO2 selectivity as a function of the cobalt particle size with the highest activity and selectivity observed at a particle size of approximately 12.8nm. Our results indicate that the overall performance of acetone steam reforming is related to a combination of particle-size-dependent acetone decomposition, water dissociation, and the oxidation state of the cobalt nanoparticles.

  3. Evaluation of Direct Aqueous Injection Method for Analysis of Chloroform in Drinking Water

    ERIC Educational Resources Information Center

    Pfaender, Frederic K.; And Others

    1978-01-01

    A direct aqueous injection (DAI) technique was compared with the purge method for chloroform measurement in drinking water. The DAI method gave consistently higher values for chloroform than the purge method. The results indicated the need for caution in the interpretation of chloroform and other trihalomethane values generated by DAI. (Author/MA)

  4. Studies on the toxicity and maximum allowable concentration of chloroform.

    PubMed

    Li, L H; Jiang, X Z; Liang, Y X; Chen, Z Q; Zhou, Y F; Wang, Y L

    1993-06-01

    Chloroform has obvious hepato-, nephro-toxicity and carcinogenicity. In order to get necessary data for recommendation of maximum allowable concentration of chloroform in workplace, a series of studies were carried out. The results showed that exposed workers mainly distributed in the industries of perspex processing, production of refrigerants, drugs and pesticides. The exposure level ranged 4.27-147.91 mg/m3 in 119 air samples collected from 3 representative worksites, with 45.4% air samples below 20 mg/m3. The workers exposed to chloroform at 29.51 mg/m3 had slight liver damage indicated by the higher rates of abnormal serum prealbumin and transferrin levels than those of control workers. The neurobehavioral functions of these workers were also obviously affected, manifested as increases in scores of passive mood states and dose-related negative changes in neurobehavioral testing. The observed effect threshold concentration of subacute inhalation in rats was 592 mg/m3 according to the observation on the biochemical changes in liver tissue and abnormal activities of serum enzymes. Mainly based on the above results, we recommended 20 mg/m3 as the Maximum Allowable Concentration in workplace in China at present. PMID:8397901

  5. Graphene oxide and adsorption of chloroform: A density functional study

    NASA Astrophysics Data System (ADS)

    Kuisma, Elena; Hansson, C. Fredrik; Lindberg, Th. Benjamin; Gillberg, Christoffer A.; Idh, Sebastian; Schröder, Elsebeth

    2016-05-01

    Chlorinated hydrocarbon compounds are of environmental concerns, since they are toxic to humans and other mammals, and are widespread, and exposure is hard to avoid. Understanding and improving methods to reduce the amount of the substances are important. We present an atomic-scale calculational study of the adsorption of chlorine-based substance chloroform (CHCl3) on graphene oxide, as a step in estimating the capacity of graphene oxide for filtering out such substances, e.g., from drinking water. The calculations are based on density functional theory, and the recently developed consistent-exchange functional for the van der Waals density-functional method is employed. We obtain values of the chloroform adsorption energy varying from roughly 0.2 to 0.4 eV per molecule. This is comparable to previously found results for chloroform adsorbed directly on clean graphene, using similar calculations. In a wet environment, like filters for drinking water, the graphene will not stay clean and will likely oxidize, and thus adsorption onto graphene oxide, rather than clean graphene, is a more relevant process to study.

  6. Graphene oxide and adsorption of chloroform: A density functional study.

    PubMed

    Kuisma, Elena; Hansson, C Fredrik; Lindberg, Th Benjamin; Gillberg, Christoffer A; Idh, Sebastian; Schröder, Elsebeth

    2016-05-14

    Chlorinated hydrocarbon compounds are of environmental concerns, since they are toxic to humans and other mammals, and are widespread, and exposure is hard to avoid. Understanding and improving methods to reduce the amount of the substances are important. We present an atomic-scale calculational study of the adsorption of chlorine-based substance chloroform (CHCl3) on graphene oxide, as a step in estimating the capacity of graphene oxide for filtering out such substances, e.g., from drinking water. The calculations are based on density functional theory, and the recently developed consistent-exchange functional for the van der Waals density-functional method is employed. We obtain values of the chloroform adsorption energy varying from roughly 0.2 to 0.4 eV per molecule. This is comparable to previously found results for chloroform adsorbed directly on clean graphene, using similar calculations. In a wet environment, like filters for drinking water, the graphene will not stay clean and will likely oxidize, and thus adsorption onto graphene oxide, rather than clean graphene, is a more relevant process to study. PMID:27179497

  7. Measuring breath acetone for monitoring fat loss: Review

    PubMed Central

    2015-01-01

    Objective Endogenous acetone production is a by‐product of the fat metabolism process. Because of its small size, acetone appears in exhaled breath. Historically, endogenous acetone has been measured in exhaled breath to monitor ketosis in healthy and diabetic subjects. Recently, breath acetone concentration (BrAce) has been shown to correlate with the rate of fat loss in healthy individuals. In this review, the measurement of breath acetone in healthy subjects is evaluated for its utility in predicting fat loss and its sensitivity to changes in physiologic parameters. Results BrAce can range from 1 ppm in healthy non‐dieting subjects to 1,250 ppm in diabetic ketoacidosis. A strong correlation exists between increased BrAce and the rate of fat loss. Multiple metabolic and respiratory factors affect the measurement of BrAce. BrAce is most affected by changes in the following factors (in descending order): dietary macronutrient composition, caloric restriction, exercise, pulmonary factors, and other assorted factors that increase fat metabolism or inhibit acetone metabolism. Pulmonary factors affecting acetone exchange in the lung should be controlled to optimize the breath sample for measurement. Conclusions When biologic factors are controlled, BrAce measurement provides a non‐invasive tool for monitoring the rate of fat loss in healthy subjects. PMID:26524104

  8. An Acetone Nanosensor For Non-invasive Diabetes Detection

    NASA Astrophysics Data System (ADS)

    Wang, L.; Yun, X.; Stanacevic, M.; Gouma, P. I.

    2009-05-01

    Diabetes is a most common disease worldwide. Acetone in exhaled breath is a known biomarker of Type- 1 diabetes. An exhaled breath analyzer has been developed with the potential to diagnose diabetes as a non-invasive alternative of the currently used blood-based diagnostics. This device utilizes a chemiresistor based on ferroelectric tungsten oxide nanoparticles and detects acetone selectively in breath-simulated media. Real-time monitoring of the acetone concentration is feasible, potentially making this detector a revolutionary, non- invasive, diabetes diagnostic tool.

  9. HEALTH AND ENVIRONMENTAL EFFECTS PROFILE FOR ACETONE CYANOHYDRIN

    EPA Science Inventory

    The Health and Environmental Effects Profile for acetone cyanohydrin was prepared by the Office of Health and Environmental Assessment, Environmental Criteria and Assessment Office, Cincinnati, OH for the Office of Solid Waste and Emergency Response to support listings of hazardo...

  10. Toward Portable Breath Acetone Analysis for Diabetes Detection

    PubMed Central

    Righettoni, Marco; Tricoli, Antonio

    2013-01-01

    Diabetes is a lifelong condition that may cause death and seriously affects the quality of life of a rapidly growing number of individuals. Acetone is a selective breath marker for diabetes that may contribute to the monitoring of related metabolic disorder and thus simplify the management of this illness. Here, the overall performance of Si-doped WO3 nanoparticles made by flame spray pyrolysis as portable acetone detectors is critically reviewed focusing on the requirements for medical diagnostic. The effect of flow rate, chamber volume and acetone dissociation within the measuring chamber are discussed with respect to the calibration of the sensor response. The challenges for the fabrication of portable breath acetone sensors based on chemo-resistive detectors are underlined indicating possible solutions and novel research directions. PMID:21828897

  11. Acetone sensor based on zinc oxide hexagonal tubes

    SciTech Connect

    Hastir, Anita Singh, Onkar Anand, Kanika Singh, Ravi Chand

    2014-04-24

    In this work hexagonal tubes of zinc oxide have been synthesized by co-precipitation method. For structural, morphological, elemental and optical analysis synthesized powders were characterized by using x-ray diffraction, field emission scanning microscope, EDX, UV-visible and FTIR techniques. For acetone sensing thick films of zinc oxide have been deposited on alumina substrate. The fabricated sensors exhibited maximum sensing response towards acetone vapour at an optimum operating temperature of 400°C.

  12. Extraction of defatted rice bran with subcritical aqueous acetone.

    PubMed

    Chiou, Tai-Ying; Neoh, Tze Loon; Kobayashi, Takashi; Adachi, Shuji

    2012-01-01

    Defatted rice bran extracts were obtained by subcritical treatment using aqueous acetone as extractant. Treatment with 40% (v/v) acetone at 230 °C for 5 min yielded an extract with the highest 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (0.274 mmol of ascorbic acid/g of bran), total carbohydrate (0.188 g/g of bran), protein (0.512 g/g of bran), and total phenolic contents (88.2 mg of gallic acid/g of bran). The effect of treatment temperature (70-230 °C) was investigated using 40% (v/v) acetone, and the extract under 230 °C treatment showed the highest levels of all the determinations described above. The extracts obtained with various concentrations of aqueous acetone were subjected to UV absorption spectra and HPLC analysis, and the results showed changes in composition and polarity. Antioxidative activity evaluated against oxidation of bulk linoleic acid of the extract obtained with 80% (v/v) acetone was higher than that not only of the extract from subcritical water treatment but also of that obtained 40% (v/v) acetone treatment. PMID:22878207

  13. Activation of Acetone and Other Simple Ketones in Anaerobic Bacteria.

    PubMed

    Heider, Johann; Schühle, Karola; Frey, Jasmin; Schink, Bernhard

    2016-01-01

    Acetone and other ketones are activated for subsequent degradation through carboxylation by many nitrate-reducing, phototrophic, and obligately aerobic bacteria. Acetone carboxylation leads to acetoacetate, which is subsequently activated to a thioester and degraded via thiolysis. Two different types of acetone carboxylases have been described, which require either 2 or 4 ATP equivalents as an energy supply for the carboxylation reaction. Both enzymes appear to combine acetone enolphosphate with carbonic phosphate to form acetoacetate. A similar but more complex enzyme is known to carboxylate the aromatic ketone acetophenone, a metabolic intermediate in anaerobic ethylbenzene metabolism in denitrifying bacteria, with simultaneous hydrolysis of 2 ATP to 2 ADP. Obligately anaerobic sulfate-reducing bacteria activate acetone to a four-carbon compound as well, but via a different process than bicarbonate- or CO2-dependent carboxylation. The present evidence indicates that either carbon monoxide or a formyl residue is used as a cosubstrate, and that the overall ATP expenditure of this pathway is substantially lower than in the known acetone carboxylase reactions. PMID:26958851

  14. Mosquito larvicidal properties of Orthisiphon thymiflorus (Roth) Sleesen. (Family: Labiatae) against mosquito vectors, Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti (Diptera: Culicidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Objective: To determine the larvicidal activity of hexane, chloroform, ethyl acetate, acetone, and methanol extracts of Orthosiphon thymiflorus leaves against Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti. Methods: Larvicidal activity was determined in laboratory bioassays using var...

  15. A Bayesian population PBPK model for multiroute chloroform exposure

    PubMed Central

    Yang, Yuching; Xu, Xu; Georgopoulos, Panos G.

    2011-01-01

    A Bayesian hierarchical model was developed to estimate the parameters in a physiologically based pharmacokinetic (PBPK) model for chloroform using prior information and biomarker data from different exposure pathways. In particular, the model provides a quantitative description of the changes in physiological parameters associated with hot-water bath and showering scenarios. Through Bayesian inference, uncertainties in the PBPK parameters were reduced from the prior distributions. Prediction of biomarker data with the calibrated PBPK model was improved by the calibration. The posterior results indicate that blood flow rates varied under two different exposure scenarios, with a two-fold increase of the skin's blood flow rate predicted in the hot-bath scenario. This result highlights the importance of considering scenario-specific parameters in PBPK modeling. To demonstrate the application of a probability approach in toxicological assessment, results from the posterior distributions from this calibrated model were used to predict target tissue dose based on the rate of chloroform metabolized in liver. This study demonstrates the use of the Bayesian approach to optimize PBPK model parameters for typical household exposure scenarios. PMID:19471319

  16. Quantitative Clinical Diagnostic Analysis of Acetone in Human Blood by HPLC: A Metabolomic Search for Acetone as Indicator

    PubMed Central

    Akgul Kalkan, Esin; Sahiner, Mehtap; Ulker Cakir, Dilek; Alpaslan, Duygu; Yilmaz, Selehattin

    2016-01-01

    Using high-performance liquid chromatography (HPLC) and 2,4-dinitrophenylhydrazine (2,4-DNPH) as a derivatizing reagent, an analytical method was developed for the quantitative determination of acetone in human blood. The determination was carried out at 365 nm using an ultraviolet-visible (UV-Vis) diode array detector (DAD). For acetone as its 2,4-dinitrophenylhydrazone derivative, a good separation was achieved with a ThermoAcclaim C18 column (15 cm × 4.6 mm × 3 μm) at retention time (tR) 12.10 min and flowrate of 1 mL min−1 using a (methanol/acetonitrile) water elution gradient. The methodology is simple, rapid, sensitive, and of low cost, exhibits good reproducibility, and allows the analysis of acetone in biological fluids. A calibration curve was obtained for acetone using its standard solutions in acetonitrile. Quantitative analysis of acetone in human blood was successfully carried out using this calibration graph. The applied method was validated in parameters of linearity, limit of detection and quantification, accuracy, and precision. We also present acetone as a useful tool for the HPLC-based metabolomic investigation of endogenous metabolism and quantitative clinical diagnostic analysis. PMID:27298750

  17. Acetone production with metabolically engineered strains of Acetobacterium woodii.

    PubMed

    Hoffmeister, Sabrina; Gerdom, Marzena; Bengelsdorf, Frank R; Linder, Sonja; Flüchter, Sebastian; Öztürk, Hatice; Blümke, Wilfried; May, Antje; Fischer, Ralf-Jörg; Bahl, Hubert; Dürre, Peter

    2016-07-01

    Expected depletion of oil and fossil resources urges the development of new alternative routes for the production of bulk chemicals and fuels beyond petroleum resources. In this study, the clostridial acetone pathway was used for the formation of acetone in the acetogenic bacterium Acetobacterium woodii. The acetone production operon (APO) containing the genes thlA (encoding thiolase A), ctfA/ctfB (encoding CoA transferase), and adc (encoding acetoacetate decarboxylase) from Clostridium acetobutylicum were cloned under the control of the thlA promoter into four vectors having different replicons for Gram-positives (pIP404, pBP1, pCB102, and pCD6). Stable replication was observed for all constructs. A. woodii [pJIR_actthlA] achieved the maximal acetone concentration under autotrophic conditions (15.2±3.4mM). Promoter sequences of the genes ackA from A. woodii and pta-ack from C. ljungdahlii were determined by primer extension (PEX) and cloned upstream of the APO. The highest acetone production in recombinant A. woodii cells was achieved using the promoters PthlA and Ppta-ack. Batch fermentations using A. woodii [pMTL84151_actthlA] in a bioreactor revealed that acetate concentration had an effect on the acetone production, due to the high Km value of the CoA transferase. In order to establish consistent acetate concentration within the bioreactor and to increase biomass, a continuous fermentation process for A. woodii was developed. Thus, acetone productivity of the strain A. woodii [pMTL84151_actthlA] was increased from 1.2mgL(-1)h(-1) in bottle fermentation to 26.4mgL(-1)h(-1) in continuous gas fermentation. PMID:26971669

  18. Acetone in the atmosphere: Distribution, sources, and sinks

    NASA Technical Reports Server (NTRS)

    Singh, H. B.; O'Hara, D.; Herlth, D.; Sachse, W.; Blake, D. R.; Bradshaw, J. D.; Kanakidou, M.; Crutzen, P. J.

    1994-01-01

    Acetone (CH3COCH3) was found to be the dominant nonmethane organic species present in the atmosphere sampled primarily over eastern Canada (0-6 km, 35 deg-65 deg N) during ABLE3B (July to August 1990). A concentration range of 357 to 2310 ppt (= 10(exp -12) v/v) with a mean value of 1140 +/- 413 ppt was measured. Under extremely clean conditions, generally involving Arctic flows, lowest (background) mixing ratios of 550 +/- 100 ppt were present in much of the troposphere studied. Correlations between atmospheric mixing ratios of acetone and select species such as C2H2, CO, C3H8, C2Cl4 and isoprene provided important clues to its possible sources and to the causes of its atmospheric variability. Biomass burning as a source of acetone has been identified for the first time. By using atmospheric data and three-dimensional photochemical models, a global acetone source of 40-60 Tg (= 10(exp 12) g)/yr is estimated to be present. Secondary formation from the atmospheric oxidation of precursor hydrocarbons (principally propane, isobutane, and isobutene) provides the single largest source (51%). The remainder is attributable to biomass burning (26%), direct biogenic emissions (21%), and primary anthropogenic emissions (3%). Atmospheric removal of acetone is estimated to be due to photolysis (64%), reaction with OH radicals (24%), and deposition (12%). Model calculations also suggest that acetone photolysis contributed significantly to PAN formation (100-200 ppt) in the middle and upper troposphere of the sampled region and may be important globally. While the source-sink equation appears to be roughly balanced, much more atmospheric and source data, especially from the southern hemisphere, are needed to reliably quantify the atmospheric budget of acetone.

  19. Chloroform degradation in methanogenic methanol enrichment cultures and by Methanosarcina barkeri 227.

    PubMed Central

    Bagley, D M; Gossett, J M

    1995-01-01

    The effects of methanol addition and consumption on chloroform degradation rate and product distribution in methanogenic methanol enrichment cultures and in cultures of Methanosarcina barkeri 227 were investigated. Degradation of chloroform with initial concentrations up to 27.3 microM in enrichment cultures and 4.8 microM in pure cultures was stimulated by the addition of methanol. However, methanol consumption was inhibited by as little as 2.5 microM chloroform in enrichment cultures and 0.8 microM chloroform in pure cultures, suggesting that the presence of methanol, not its exact concentration or consumption rate, was the most significant variable affecting chloroform degradation rate. Methanol addition also significantly increased the number of moles of dichloromethane produced per mole of chloroform consumed. In enrichment cultures, the number of moles of dichloromethane produced per mole of chloroform consumed ranged from 0.7 (methanol consumption essentially uninhibited) to 0.35 (methanol consumption significantly inhibited) to less than 0.2 (methanol not added to the culture). In pure cultures, the number of moles of dichloromethane produced per mole of chloroform consumed was 0.47 when methanol was added and 0.24 when no methanol was added. Studies with [14C]chloroform in both enrichment and pure cultures confirmed that methanol metabolism stimulated dichloromethane production compared with CO2 production. The results indicate that while the addition of methanol significantly stimulated chloroform degradation in both methanogenic methanol enrichment cultures and cultures of M. barkeri 227, the prospects for use of methanol as a growth substrate for anaerobic chloroform-degrading systems may be limited unless the increased production of undesirable chloroform degradation products and the inhibition of methanol consumption can be mitigated. PMID:7574627

  20. 21 CFR 700.18 - Use of chloroform as an ingredient in cosmetic products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... animals. Studies conducted by the National Cancer Institute have demonstrated that the oral administration of chloroform to mice and rats induced hepatocellular carcinomas (liver cancer) in mice and...

  1. 21 CFR 700.18 - Use of chloroform as an ingredient in cosmetic products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... animals. Studies conducted by the National Cancer Institute have demonstrated that the oral administration of chloroform to mice and rats induced hepatocellular carcinomas (liver cancer) in mice and...

  2. 21 CFR 700.18 - Use of chloroform as an ingredient in cosmetic products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... animals. Studies conducted by the National Cancer Institute have demonstrated that the oral administration of chloroform to mice and rats induced hepatocellular carcinomas (liver cancer) in mice and...

  3. 21 CFR 700.18 - Use of chloroform as an ingredient in cosmetic products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... animals. Studies conducted by the National Cancer Institute have demonstrated that the oral administration of chloroform to mice and rats induced hepatocellular carcinomas (liver cancer) in mice and...

  4. 21 CFR 700.18 - Use of chloroform as an ingredient in cosmetic products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... animals. Studies conducted by the National Cancer Institute have demonstrated that the oral administration of chloroform to mice and rats induced hepatocellular carcinomas (liver cancer) in mice and...

  5. Calculated Third Order Rate Constants for Interpreting the Mechanisms of Hydrolyses of Chloroformates, Carboxylic Acid Halides, Sulfonyl Chlorides and Phosphorochloridates

    PubMed Central

    Bentley, T. William

    2015-01-01

    Hydrolyses of acid derivatives (e.g., carboxylic acid chlorides and fluorides, fluoro- and chloroformates, sulfonyl chlorides, phosphorochloridates, anhydrides) exhibit pseudo-first order kinetics. Reaction mechanisms vary from those involving a cationic intermediate (SN1) to concerted SN2 processes, and further to third order reactions, in which one solvent molecule acts as the attacking nucleophile and a second molecule acts as a general base catalyst. A unified framework is discussed, in which there are two reaction channels—an SN1-SN2 spectrum and an SN2-SN3 spectrum. Third order rate constants (k3) are calculated for solvolytic reactions in a wide range of compositions of acetone-water mixtures, and are shown to be either approximately constant or correlated with the Grunwald-Winstein Y parameter. These data and kinetic solvent isotope effects, provide the experimental evidence for the SN2-SN3 spectrum (e.g., for chloro- and fluoroformates, chloroacetyl chloride, p-nitrobenzoyl p-toluenesulfonate, sulfonyl chlorides). Deviations from linearity lead to U- or V-shaped plots, which assist in the identification of the point at which the reaction channel changes from SN2-SN3 to SN1-SN2 (e.g., for benzoyl chloride). PMID:26006228

  6. Sensor gas analyzer for acetone determination in expired air

    NASA Astrophysics Data System (ADS)

    Baranov, Vitaly V.

    2001-05-01

    Diseases and changes in the way of life change the concentration and composition of the expired air. Our adaptable gas analyzer is intended for the selective analysis of expired air and can be adapted for the solution of current diagnostic and analytical tasks by the user (a physician or a patient). Having analyzed the existing trends in the development of noninvasive diagnostics we have chosen the method of noninvasive acetone detection in expired air, where the acetone concentration correlates with blood and urine glucose concentrations. The appearance of acetone in expired air is indicative of disorders that may be caused not only by diabetes but also be wrong diet, incorrect sportsmen training etc. To control the disorders one should know the acetone concentration in the human body. This knowledge allows one to judge upon the state of the patient, choose a correct diet that will not cause damage to the patient's health, determine sportsmen training efficiency and results and solve the artificial pancreas problem. Our device provide highly accurate analysis, rapid diagnostics and authentic acetone quantification in the patient's body at any time aimed at prediction of the patient's state and assessing the efficiency of the therapy used. Clinical implementation of the device will improve the health and save lives of many thousands of diabetes sufferers.

  7. Nitrate-Dependent Degradation of Acetone by Alicycliphilus and Paracoccus Strains and Comparison of Acetone Carboxylase Enzymes ▿

    PubMed Central

    Dullius, Carlos Henrique; Chen, Ching-Yuan; Schink, Bernhard

    2011-01-01

    A novel acetone-degrading, nitrate-reducing bacterium, strain KN Bun08, was isolated from an enrichment culture with butanone and nitrate as the sole sources of carbon and energy. The cells were motile short rods, 0.5 to 1 by 1 to 2 μm in size, which gave Gram-positive staining results in the exponential growth phase and Gram-negative staining results in the stationary-growth phase. Based on 16S rRNA gene sequence analysis, the isolate was assigned to the genus Alicycliphilus. Besides butanone and acetone, the strain used numerous fatty acids as substrates. An ATP-dependent acetone-carboxylating enzyme was enriched from cell extracts of this bacterium and of Alicycliphilus denitrificans K601T by two subsequent DEAE Sepharose column procedures. For comparison, acetone carboxylases were enriched from two additional nitrate-reducing bacterial species, Paracoccus denitrificans and P. pantotrophus. The products of the carboxylase reaction were acetoacetate and AMP rather than ADP. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis of cell extracts and of the various enzyme preparations revealed bands corresponding to molecular masses of 85, 78, and 20 kDa, suggesting similarities to the acetone carboxylase enzymes described in detail for the aerobic bacterium Xanthobacter autotrophicus strain Py2 (85.3, 78.3, and 19.6 kDa) and the phototrophic bacterium Rhodobacter capsulatus. Protein bands were excised and compared by mass spectrometry with those of acetone carboxylases of aerobic bacteria. The results document the finding that the nitrate-reducing bacteria studied here use acetone-carboxylating enzymes similar to those of aerobic and phototrophic bacteria. PMID:21841031

  8. Phase transition in conjugated oligomers suspended in chloroform

    NASA Astrophysics Data System (ADS)

    Dwivedi, Shikha; Kumar, Anupam; Yadav, S. N. S.; Mishra, Pankaj

    2015-08-01

    Density functional theory (DFT) has been used to investigate the isotropic-nematic (I-N) phase transition in a system of high aspect ratio conjugated oligomers suspended in chloroform. The interaction between the oligomers is modeled using Gay-Berne potential in which effect of solvent is implicit. Percus-Yevick integral equation theory has been used to evaluate the pair correlation functions of the fluid phase at several temperatures and densities. These pair correlation function has been used in the DFT to evaluate the I-N freezing parameters. Highly oriented nematic is found to stabilize at low density. The results obtained are in qualitative agreement with the simulation and are verifiable.

  9. Atmospheric halocarbons - A discussion with emphasis on chloroform

    NASA Technical Reports Server (NTRS)

    Yung, Y. L.; Mcelroy, M. B.; Wofsy, S. C.

    1975-01-01

    Bleaching of paper pulp represents a major industrial use of chlorine and could provide an environmentally significant source of atmospheric halocarbons. The related global production of chloroform is estimated at 300,000 ton per year and there could be additional production associated with atmospheric decomposition of perchloroethylene. Estimates are given for the production of methyl chloride, methyl bromide and methyl iodide, 5.2 million, 77 thousand, and 740 thousand ton per year respectively. The relative yields of CH3Cl, CH3Br and CH3I are consistent with the hypothesis of a marine biological source for these compounds. Concentrations of other halocarbons observed in the atmosphere appear to indicate industrial sources.

  10. Antibacterial mechanism and activities of black pepper chloroform extract.

    PubMed

    Zou, Lan; Hu, Yue-Ying; Chen, Wen-Xue

    2015-12-01

    Black pepper extracts reportedly inhibit food spoilage and food pathogenic bacteria. This study explored the antimicrobial activity of black pepper chloroform extract (BPCE) against Escherichia coli and Staphylococcus aureus. The antibacterial mechanism of BPCE was elucidated by analyzing the cell morphology, respiratory metabolism, pyruvic acid content, and ATP levels of the target bacteria. Scanning electron micrographs showed that the bacterial cells were destroyed and that plasmolysis was induced. BPCE inhibited the tricarboxylic acid pathway of the bacteria. The extract significantly increased pyruvic acid concentration in bacterial solutions and reduced ATP level in bacterial cells. BPCE destroyed the permeability of the cell membrane, which consequently caused metabolic dysfunction, inhibited energy synthesis, and triggered cell death. PMID:26604394

  11. Isopropanol and acetone induces vinyl chloride degradation in Rhodococcus rhodochrous.

    PubMed

    Kuntz, Robin L; Brown, Lewis R; Zappi, Mark E; French, W Todd

    2003-11-01

    In situ bioremediation of vinyl chloride (VC)-contaminated waste sites requires a microorganism capable of degrading VC. While propane will induce an oxygenase to accomplish this goal, its use as a primary substrate in bioremediation is complicated by its flammability and low water solubility. This study demonstrates that two degradation products of propane, isoproponal and acetone, can induce the enzymes in Rhodococcus rhodochrous that degrade VC. Additionally, a reasonable number of cells for bioremediation can be grown on conventional solid bacteriological media (nutrient agar, tryptic soy agar, plate count agar) in an average microbiological laboratory and then induced to produce the necessary enzymes by incubation of a resting cell suspension with isopropanol or acetone. Since acetone is more volatile than isopropanol and has other undesirable characteristics, isopropanol is the inducer of choice. It offers a non-toxic, water-soluble, relatively inexpensive alternative to propane for in situ bioremediation of waste sites contaminated with VC. PMID:14605909

  12. Is interstellar acetone produced by ion-molecule chemistry?

    NASA Astrophysics Data System (ADS)

    Herbst, Eric; Giles, Kevin; Smith, David

    1990-08-01

    The rate coefficient for the ion-molecule radiative association reaction CH3(+) + CH3CHO - (CH3)2CHO(+) has bee calculated in the range 10-300 K with the phase-space techique and the aid of a laboratory measurement of the analogous three-body association at room temperature. It has been suggested by Combes et al. (1987) that this reaction followed by dissociative recombination is responsible for the observed abundance of acetone (CH3COCH3) in Sgr B2. However, it is shown here that the radiative association reaction is probably too slow even at 10 K to lead to the observed abundance of acetone in this source. The question of how acetone is produced in Sgr B2 is thus still unanswered.

  13. Acetone Powder From Dormant Seeds of Ricinus communis L

    NASA Astrophysics Data System (ADS)

    Cavalcanti, Elisa D. C.; Maciel, Fábio M.; Villeneuve, Pierre; Lago, Regina C. A.; Machado, Olga L. T.; Freire, Denise M. G.

    The influence of several factors on the hydrolytic activity of lipase, present in the acetone powder from dormant castor seeds (Ricinus communis) was evaluated. The enzyme showed a marked specificity for short-chain substrates. The best reaction conditions were an acid medium, Triton X-100 as the emulsifying agent and a temperature of 30°C. The lipase activity of the acetone powder of different castor oil genotypes showed great variability and storage stability of up to 90%. The toxicology analysis of the acetone powder from genotype Nordestina BRS 149 showed a higher ricin (toxic component) content, a lower 2S albumin (allergenic compound) content, and similar allergenic potential compared with untreated seeds.

  14. Specific Anion Effects on the Kinetics of Iodination of Acetone.

    PubMed

    Lo Nostro, Pierandrea; Mazzini, Virginia; Ninham, Barry W; Ambrosi, Moira; Dei, Luigi; Baglioni, Piero

    2016-08-18

    Specific ion effects on the kinetics of iodination of acetone in an acidic medium are investigated by UV/Vis spectrophotometry as a function of nature of the acid and temperature. The results indicate that the order of the reaction with respect to acetone is practically unaffected by the composition of the acid while the value of the mixed constant k1 K increases according to the sequence HBr

  15. Detection of interstellar ethyl cyanide

    NASA Technical Reports Server (NTRS)

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

    1977-01-01

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

  16. S-Ethyl dipropylthiocarbamate (EPTC)

    Integrated Risk Information System (IRIS)

    S - Ethyl dipropylthiocarbamate ( EPTC ) ; CASRN 759 - 94 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessme

  17. The relationship between water concentrations and individual uptake of chloroform: a simulation study.

    PubMed Central

    Whitaker, Heather J; Nieuwenhuijsen, Mark J; Best, Nicola G

    2003-01-01

    We simulated the relationship between water chloroform concentrations and chloroform uptake in pregnant women to assess the potential extent of exposure measurement error in epidemiologic studies of the health effects of exposure to water disinfection by-products. Data from the literature were used to assign statistical distributions to swimming pool chloroform concentrations, frequency and duration of swimming, showering and bathing, and average tap water consumption. Measured increases in blood chloroform concentrations after these activities were used to estimate average uptake per microgram per liter chloroform in the water, per minute spent in the activity or per liter consumed. Given average tap water chloroform concentrations from a U.K. epidemiologic study, an average daily uptake over 90 days was simulated for 300,000 mothers. The correlation between simulated uptakes and home tap chloroform concentration was 0.6. Mothers who swam regularly received far greater doses than did nonswimmers. Results suggest there will be considerable attenuation in risk estimates and/or power loss in epidemiologic studies if the putative agent is chloroform. PMID:12727595

  18. Transformation of chloroform in model treatment wetlands: from mass balance to microbial analysis.

    PubMed

    Chen, Yi; Wen, Yue; Zhou, Junwei; Zhou, Qi; Vymazal, Jan; Kuschk, Peter

    2015-05-19

    Chloroform is one of the common disinfection byproducts, which is not susceptible to degradation and poses great health concern. In this study, the chloroform removal efficiencies and contributions of sorption, microbial degradation, plant uptake, and volatilization were evaluated in six model constructed wetlands (CWs). The highest chloroform removal efficiency was achieved in litter-added CWs (99%), followed by planted (46-54%) and unplanted CWs (39%). Mass balance study revealed that sorption (73.5-81.2%) and microbial degradation (17.6-26.2%) were the main chloroform removal processes in litter-added CWs, and that sorption (53.6-66.1%) and plant uptake (25.3-36.2%) were the primary contributors to chloroform removal in planted CWs. Around 60% of chloroform got accumulated in the roots after plant uptake, and both transpiration and gas-phase transport were expected to be the drivers for the plant uptake. Sulfate-reducing bacteria and methanogens were found to be the key microorganisms for chloroform biodegradation through cometabolic dechlorination, and positive correlations were observed between functional genes (dsrA, mcrA) and biodegradation rates. Overall, this study suggests that wetland is an efficient ecosystem for sustainable chloroform removal, and that plant and litter can enhance the removal performance through root uptake and microbial degradation stimulation, respectively. PMID:25901522

  19. Apparent pollution of groundwater caused by natural formation of chloroform in forest soils

    NASA Astrophysics Data System (ADS)

    Jacobsen, O.; Laier, T.; Albers, C. N.; Hunkeler, D.

    2011-12-01

    Halogenated compounds are known to be formed in natural environments. Many of these compounds are similar to industrially produced compounds and are toxic or carcinogenic. High concentration of chloroform in groundwater is usually attributed to anthropogenic input, but we have found that the groundwater beneath some pristine areas contained chloroform exceeding 1 μg/L. We investigated four coniferous forests over a period of several years in order to measure the net-formation of chloroform. Field measurements of atmospheric and soil air concentrations of chloroform were monitored. Analyses of soil air at 40 cm depth in different parts of the forests and adjacent areas revealed an extremely large variation in chloroform concentration exceeding two orders of magnitude. Up to 100 ppbv was found in soil air under the spruce forest, to be compared to an ambient atmospheric concentration of 0.02 ppbv. The concentration of chloroform in soil air showed seasonal variation similar to that of CO2. Chloroform formation during incubation of undisturbed top-soil samples was found to be largest in soils from dense conifers stands with well-developed humus layers, while low chloroform formation occurred in soils from beech forest and agricultural grassland. We suggest that the mechanism behind the formation of chloroform is an unspecific chlorination of organic matter, caused by microbial activity in the soil. The aquifers are in fluvio-glacial sands with few layers of silt and a groundwater table from 4 to 7 m below the surface. In the shallowest parts of the aquifer, the groundwater has chloroform concentrations of 0.1 to 5 μg/L, and the groundwater is oxic with an age from 5 to 45 years using CFC-dating. Analyses of oxic groundwater > 40 years showed that it still contained chloroform at concentrations of 1 μg/L. Stable carbon isotopic analyses of chloroform from the uppermost groundwater in different parts of the forests and from soil water showed values from δ13C = -13

  20. NASOPHARYNGEAL CONCENTRATIONS IN THE HUMAN VOLUNTEER BREATHING ACETONE

    EPA Science Inventory

    In an effort to examine the absorption of a common chemical into the nasopharyngeal region in humans, a 57 year old male volunteer inhaled uniformly labeled 13C-acetone at 1.4 ppm for 30 min while performing different breathing maneuvers; nose inhale, nose exhale (NINE); mouth ...

  1. [Death after explosion of an "empty" acetone barrel].

    PubMed

    Preuss-Wössner, Johanna; Gerling, Ivana

    2013-01-01

    Inappropriate disposal of (hazardous) waste material led to an explosion of an acetone-air mixture in a metal barrel. The lid was blown off and caused blunt traumatization with fatal exsanguination. The case furnishes information relevant for the practical teaching of forensic knowledge and the indicated consultation of medico-legal experts already at scene. PMID:24358622

  2. [Detection and determination of acetone using semiconductor sensors].

    PubMed

    Reichel, J; Seyffarth, T; Guth, U; Möbius, H H; Göckeritz, D

    1989-10-01

    Investigations to examine not only the factors of influence on evaluation of acetone by self-prepared semiconductor gas sensors, but also to prove analytical properties, were carried out using different tools. A sensor temperature of 600 degrees C and a carrier gas flow-rate of 5 l/h were found to be suitable conditions for the measurement of flow-injection apparatus. The determination of 1 microliter-samples of aqueous solutions containing 1-700 g of acetone/l yielded deviations of 4 to 33%. Using a head space method, the working temperature of 370 degrees C led to a maximum sensor response, the detection limit ranged from 37.5 to 50 mg of acetone/l. After quantifying 5 microliters-sample solutions of 40-600 mg/l, results with an accuracy of 1 to 36% were obtained. The method showed the possibility of distinguishing concentrations of acetone below and above 40 mg/l according to physiological and pathological urinary values. The tests carried out on 100 human urine samples provide a good agreement with the Legal reference method for samples containing physiological or strong pathological amounts of ketone bodies, but not for those including traces and small amounts. False-positive results might be caused by a possible presence of ethanol in urine. PMID:2616614

  3. A fully integrated standalone portable cavity ringdown breath acetone analyzer

    NASA Astrophysics Data System (ADS)

    Sun, Meixiu; Jiang, Chenyu; Gong, Zhiyong; Zhao, Xiaomeng; Chen, Zhuying; Wang, Zhennan; Kang, Meiling; Li, Yingxin; Wang, Chuji

    2015-09-01

    Breath analysis is a promising new technique for nonintrusive disease diagnosis and metabolic status monitoring. One challenging issue in using a breath biomarker for potential particular disease screening is to find a quantitative relationship between the concentration of the breath biomarker and clinical diagnostic parameters of the specific disease. In order to address this issue, we need a new instrument that is capable of conducting real-time, online breath analysis with high data throughput, so that a large scale of clinical test (more subjects) can be achieved in a short period of time. In this work, we report a fully integrated, standalone, portable analyzer based on the cavity ringdown spectroscopy technique for near-real time, online breath acetone measurements. The performance of the portable analyzer in measurements of breath acetone was interrogated and validated by using the certificated gas chromatography-mass spectrometry. The results show that this new analyzer is useful for reliable online (online introduction of a breath sample without pre-treatment) breath acetone analysis with high sensitivity (57 ppb) and high data throughput (one data per second). Subsequently, the validated breath analyzer was employed for acetone measurements in 119 human subjects under various situations. The instrument design, packaging, specifications, and future improvements were also described. From an optical ringdown cavity operated by the lab-set electronics reported previously to this fully integrated standalone new instrument, we have enabled a new scientific tool suited for large scales of breath acetone analysis and created an instrument platform that can even be adopted for study of other breath biomarkers by using different lasers and ringdown mirrors covering corresponding spectral fingerprints.

  4. Effects of combined UV and chlorine treatment on chloroform formation from triclosan.

    PubMed

    Ben, Weiwei; Sun, Peizhe; Huang, Ching-Hua

    2016-05-01

    The co-exposure to UV irradiation and free chlorine may occur in certain drinking water and wastewater treatment systems. This study investigated the effects of simultaneous low pressure ultraviolet (LPUV) irradiation and free chlorination on the formation of chloroform from triclosan which is a commonly used antibacterial agent. Different treatment systems (i.e., combined UV/chlorine, UV alone, and chlorine alone) were applied to examine the degradation of triclosan and formation of chloroform. The fate of representative intermediates, including chlorinated triclosan, dechlorinated triclosan intermediates and 2,4-dichlorophenol, were tracked to deduce the effect of combined UV/chlorine on the transformation of chloroform formation precursors. The relation between intermediates degradation and chloroform formation was investigated in depth by conducting stepwise experiments with UV and chlorine in different sequences. Results indicate that the combined UV/chlorine notably enhanced the chloroform formation from triclosan. From the reaction mechanism perspective the combined UV/chlorine, where the direct photolysis may play an important role, could accelerate the decay of intermediates and facilitate the generation of productive chloroform precursors. The radicals had modest influence on the degradation of triclosan and intermediates and partly hindered the formation of chloroform. These results emphasize the necessity of considering disinfection by-products formation in the application of combined UV/chlorine technology during water treatment. PMID:26746417

  5. Adaptive tolerance in mice upon subchronic exposure to chloroform: Increased exhalation and target tissue regeneration

    SciTech Connect

    Anand, Sathanandam S. . E-mail: sanand@rx.uga.edu; Philip, Binu K.; Palkar, Prajakta S.; Mumtaz, Moiz M.; Latendresse, John R.; Mehendale, Harihara M. . E-mail: mehendale@ulm.edu

    2006-06-15

    The aims of the present study were to characterize the subchronic toxicity of chloroform by measuring tissue injury, repair, and distribution of chloroform and to assess the reasons for the development of tolerance to subchronic chloroform toxicity. Male Swiss Webster (SW) mice were given three dose levels of chloroform (150, 225, and 300 mg/kg/day) by gavage in aqueous vehicle for 30 days. Liver and kidney injury were measured by plasma ALT and BUN, respectively, and by histopathology. Tissue regeneration was assessed by {sup 3}H-thymidine incorporation into hepato- and nephro-nuclear DNA and by proliferating cell nuclear antigen staining. In addition, GSH and CYP2E1 in liver and kidney were assessed at selected time points. The levels of chloroform were measured in blood, liver, and kidney during the dosing regimen (1, 7, 14, and 30 days). Kidney injury was evident after 1 day with all three doses and sustained until 7 days followed by complete recovery. Mild to moderate liver injury was observed from 1 to 14 days with all three dose levels followed by gradual decrease. Significantly higher regenerative response was evident in liver and kidney at 7 days, but the response was robust in kidney, preventing progression of injury beyond first week of exposure. While the kidney regeneration reached basal levels by 21 days, moderate liver regeneration with two higher doses sustained through the end of the dosing regimen and 3 days after that. Following repeated exposure for 7, 14, and 30 days, the blood and tissue levels of chloroform were substantially lower with all three dose levels compared to the levels observed with single exposure. Increased exhalation of {sup 14}C-chloroform after repeated exposures explains the decreased chloroform levels in circulation and tissues. These results suggest that toxicokinetics and toxicodynamics (tissue regeneration) contribute to the tolerance observed in SW mice to subchronic chloroform toxicity. Neither bioactivation nor

  6. Systemic inflammatory response due to chloroform intoxication--an uncommon complication.

    PubMed

    Dettling, A; Stadler, K; Eisenbach, C; Skopp, G; Haffner, H T

    2016-03-01

    Well-known adverse effects of chloroform are drowsiness, nausea, and liver damage. Two cases with an uncommon complication due to chloroform intoxication are presented. In the first case, a general physician, because of nausea and dyspnea, admitted a 34-year-old woman to hospital. She developed a toxic pulmonary edema requiring mechanical ventilation for a few days, and a systemic inflammatory response syndrome (SIRS) with elevated white blood cell counts, a moderate increase of C-reactive protein, and slightly elevated procalcitonin levels. There were inflammatory altered skin areas progressing to necrosis later on. However, bacteria could be detected neither in blood culture nor in urine. Traces of chloroform were determined from a blood sample, which was taken 8 h after admission. Later, the husband confessed to the police having injected her chloroform and put a kerchief soaked with chloroform over her nose and mouth. In the second case, a 50-year-old man ingested chloroform in a suicidal attempt. He was found unconscious in his house and referred to a hospital. In the following days, he developed SIRS without growth of bacteria in multiple blood cultures. He died several days after admission due to multi-organ failure. SIRS in response to chloroform is a rare but severe complication clinically mimicking bacterial-induced sepsis. The mechanisms leading to systemic inflammation after chloroform intoxication are currently unclear. Possibly, chloroform and/or its derivates may interact with pattern recognition receptors and activate the same pro-inflammatory mediators (cytokines, interleukins, prostaglandins, leukotrienes) that cause SIRS in bacterial sepsis. PMID:25676899

  7. Chloroform formation in Arctic and Subarctic soils - mechanism and emissions to the atmosphere

    NASA Astrophysics Data System (ADS)

    Albers, Christian N.; Johnsen, Anders R.; Jacobsen, Ole S.

    2015-04-01

    It is well established that halogenated organic compounds are formed naturally in the terrestrial environment. These compounds include volatiles such as trihalomethanes that may escape to the atmosphere. In deed most of the atmospheric chloroform (and other trihalomethane species) is regarded to have a natural origin. This origin may be both marine and terrestrial. Chloroform formation in soil has been reported in a number of studies, mostly conducted in temperate and (sub-) tropical environments. We hereby report that also colder soils emit chloroform naturally. We measured in situ the fluxes of chloroform from soil to atmosphere in 6 Subarctic and 5 Arctic areas covering different dwarf heath, wetland and forest biotopes in Greenland and Northern Sweden. Emissions were largest from the forested areas, but all areas emitted measurable amounts of chloroform. Also the brominated analog bromodichloromethane was formed in Arctic and Subarctic soils but the fluxes to the atmosphere were much lower than the corresponding chloroform emissions. No other volatile poly-halogenated organic compounds were found to be emitted from the study areas. It has previously been proposed that chloroform is formed in temperate forest soils through trichloroacetyl intermediates formed by unspecific enzymatic chlorination of soil organic matter. We found positive relationships between chloroform emissions and the concentration of trichloroacetyl groups in soil within the various biotopes. The hydrolysis of trichloroacetyl compounds is, however, very pH dependent, excluding a simple relationship between trichloroacetyl concentration and chloroform emission in any given soil. However, our results show that at low pH, turnover time of soil trichloroacetyl compounds may be counted in decades while at pH above 6, turnover time may be just a few months. We found no relationship between trichloroacetyl concentration and total organic chlorine concentration in the soils indicating that more than

  8. Simultaneous derivatisation and preconcentration of parabens in food and other matrices by isobutyl chloroformate and dispersive liquid-liquid microextraction followed by gas chromatographic analysis.

    PubMed

    Jain, Rajeev; Mudiam, Mohana Krishna Reddy; Chauhan, Abhishek; Ch, Ratnasekhar; Murthy, R C; Khan, Haider A

    2013-11-01

    A simple, rapid and economical method has been proposed for the quantitative determination of parabens (methyl, ethyl, propyl and butyl paraben) in different samples (food, cosmetics and water) based on isobutyl chloroformate (IBCF) derivatisation and preconcentration using dispersive liquid-liquid microextraction in single step. Under optimum conditions, solid samples were extracted with ethanol (disperser solvent) and 200 μL of this extract along with 50 μL of chloroform (extraction solvent) and 10 μL of IBCF was rapidly injected into 2 mL of ultra-pure water containing 150 μL of pyridine to induce formation of a cloudy state. After centrifugation, 1 μL of the sedimented phase was analysed using gas chromatograph-flame ionisation detector (GC-FID) and the peaks were confirmed using gas chromatograph-positive chemical ionisation-mass spectrometer (GC-PCI-MS). Method was found to be linear over the range of 0.1-10 μg mL(-1) with square of correlation coefficient (R(2)) in the range of 0.9913-0.9992. Limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.029-0.102 μg mL(-1) and 0.095-0.336 μg mL(-1) with a signal to noise ratio of 3:1 and 10:1, respectively. PMID:23768377

  9. Measurement of the diffusion coefficient of acetone in succinonitrile at its melting point

    NASA Technical Reports Server (NTRS)

    Chopra, M. A.; Glicksman, M. E.; Singh, N. B.

    1988-01-01

    The diffusion coefficient of acetone in liquid succinonitrile at 331.1 K was determined using the method of McBain and Dawson (1935). Only dilute mixtures of SCN-acetone were studied. The interdiffusion constant was determined to be 0.0000127 sq cm/s and was essentially independent of the acetone concentration over the range investigated (0.5 to 18 mol pct acetone).

  10. Rydberg states of chloroform studied by VUV photoabsorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Singh, Param Jeet; Shastri, Aparna; D'Souza, R.; Jagatap, B. N.

    2013-11-01

    The VUV photoabsorption spectra of CHCl3 and CDCl3 in the energy region 6.2-11.8 eV (50,000-95,000 cm-1) have been investigated using synchrotron radiation from the Indus-1 source. Rydberg series converging to the first four ionization limits at 11.48, 11.91, 12.01 and 12.85 eV corresponding to excitation from the 1a2, 4a1, 4e, 3e, orbitals of CHCl3 respectively are identified and analyzed. Quantum defect values are observed to be consistent with excitation from the chlorine lone pair orbitals. Vibrational progressions observed in the region of 72,500-76,500 cm-1 have been reassigned to ν3 and combination modes of ν3+ν6 belonging to the 1a2→4p transition in contrast to earlier studies where they were assigned to a ν3 progression superimposed on the 3e→4p Rydberg transition. The assignments are further confirmed based on isotopic substitution studies on CDCl3 whose VUV photoabsorption spectrum is reported here for the first time. The frequencies of the ν3 and ν6 modes in the 4p Rydberg state of CHCl3 (CDCl3) are proposed to be ~454 (409) cm-1 and~130 (129) cm-1 respectively based on the vibronic analysis. DFT calculations of neutral and ionic ground state vibrational frequencies support the vibronic analysis. Experimental spectrum is found to be in good agreement with that predicted by TDDFT calculations. This work presents a consolidated analysis of the VUV photoabsorption spectrum of chloroform.

  11. Contribution of natural terrestrial sources to the atmospheric chloroform budget

    NASA Astrophysics Data System (ADS)

    Rhew, R. C.; Abel, T.; Pan, D.; Whelan, M.

    2008-12-01

    Chloroform (trichloromethane, CHCl3) is the second largest carrier of natural chlorine in the troposphere after methyl chloride, contributing to the reactive chlorine burden in the troposphere and to ozone destruction in the stratosphere. Our understanding of the biogeochemical cycling of atmospheric CHCl3 has undergone major adjustments recently, including the quantification of the total atmospheric burden of this compound, the estimated global source and sink strengths, and the relative contributions of anthropogenic versus natural contributions. Numerous natural terrestrial sources have been identified, including temperate peatlands, Arctic tundra, termite mounds, salt marshes, grasslands, forests and woodlands. However, the wide variability of fluxes within each ecosystem has complicated efforts to quantify the overall terrestrial source. In addition, the environmental and biogeochemical controls remain largely unknown. We shall present a comparison of recent CHCl3 flux measurements that cover a range of biome types and climatic conditions. To address within-biome variability, flux measurements from the Arctic tundra and temperate grasslands will be compared to common environmental parameters (e.g., temperature, soil moisture, solar insolation) and other trace gas fluxes (CH3Cl, CH4, CCl4). The generally poor correlations demonstrate that the variability of CHCl3 emissions may be affected by site-specific parameters that are not currently measured or by drastic changes in hydrologic conditions. Similar patterns are observed in laboratory incubations of tundra peat and grassland soils. We explore the possibility that the humification of plant material, which has been shown to produce organochlorine compounds through the chlorination of organic matter, may contribute to CHCl3 emissions. If this link exists, then CHCl3 production could potentially act as a proxy for organic matter degradation and carbon sequestration, essential biogeochemical and ecosystem

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

    PubMed Central

    D’Souza, Malcolm J.; Givens, Aaron F.; Lorchak, Peter A.; Greenwood, Abigail E.; Gottschall, Stacey L.; Carter, Shannon E.; Kevill, Dennis N.

    2013-01-01

    At 25.0 °C the specific rates of solvolysis for allyl and vinyl chloroformates have been determined in a wide mix of pure and aqueous organic mixtures. In all the solvents studied, vinyl chloroformate was found to react significantly faster than allyl chloroformate. Multiple correlation analyses of these rates are completed using the extended (two-term) Grunwald-Winstein equation with incorporation of literature values for solvent nucleophilicity (NT) and solvent ionizing power (YCl). Both substrates were found to solvolyze by similar dual bimolecular carbonyl-addition and unimolecular ionization channels, each heavily dependent upon the solvents nucleophilicity and ionizing ability. PMID:23549265

  13. Enhancement of the Hepatotoxicity of chloroform in B6C3F1 mice by corn oil: implications for chloroform carcinogenesis

    SciTech Connect

    Bull, R.J.; Brown, J.M.; Meierhenry, E.A.; Jorgenson, T.A.; Robinson, M.; Stober, J.A.

    1986-11-01

    A recent study of the ability of chloroform in drinking water to produce cancer reported that male Osborne-Mendel rats developed renal tumors, but that female B6C3F1 mice failed to develop hepatocellular carcinomas. The results obtained in the male Osborne-Mendel rats were comparable to those observed in an earlier study sponsored by the National Cancer Institute (NCI). On the other hand, the lack of an increased incidence of hepatocellular carcinomas in female B6C3F1 mice was in sharp contrast to previously reported results. The doses of chloroform used were comparable to that which produced an 85% incidence in the NCI study. The authors have investigated the extent to which the vehicle might be responsible for the different results in these two studies by examining the differential effects of chloroform when it was administered by gavage using corn oil versus a 2% Emulphor suspension as the vehicle. Male and female B6C3F1 mice were administered chloroform at 60, 130, and 270 mg/kg per day for 90 days. At sacrifice, body and organ weights were measured, and blood was recovered to perform the following serum chemistry measurements (in order of priority): glutamate oxalacetate transaminase (SGOT), lactate dehydrogenase (LDH), blood urea nitrogen (BUN), and triglyceride (TG) levels. The liver was sectioned for histopathological examination. These data indicate that administration of chloroform by corn oil gavage results in more marked hepatotoxic effects than observed when it is provided in an aqueous suspension. A major difference between two recent carcinogenesis bioassays of chloroform in this same mouse strain was the vehicle used.

  14. Crystallization of paracetamol in acetone?water mixtures

    NASA Astrophysics Data System (ADS)

    Granberg, Roger A.; Bloch, Dan G.; Rasmuson, Åke C.

    1999-03-01

    The influence of solvent composition on the crystallization of paracetamol (4-hydroxyacetanilide) in acetone-water mixtures is investigated. Particle generation and crystal growth kinetics have been studied by batch isothermal desupersaturation experiments at constant solvent composition. The solubility exhibits a very pronounced maximum at approximately 20 wt% water. Nucleation and agglomeration increase with increasing initial supersaturation, but at a given initial supersaturation, the solvent composition has no clear influence on the product particle characteristics. The crystal growth rate is higher in pure acetone than in pure water, but the rate passes through a maximum in a mixture containing 20-25 wt% water. There is a good correlation between crystal growth rate and solubility, even though the growth rate is comparatively high at high water concentrations.

  15. Economic evaluation of the acetone-butane fermentation

    SciTech Connect

    Lenz, T.G.; Moreira, A.R.

    1980-01-01

    The economics of producing acetone as 1-butanol via fermentation have been examined for a 45 x 1 kg of solvents/year plant. For a molasses substrate the total annual production costs were approximately $39 million vs. a total annual income of $36 million, with approximatley $20 million total required capital. Molasses cost of approximately $24.4 million/year was critical to these economics. Liquid whey was next evaluated as an alternative feed. Whey feed saved approximately 11 million dollars annually in feed costs and yielded approximately 8 million net additional annual revenues from protein sale. The primary differences gave an annual gross profit of approximately $15 million for the whey case and resulted in a discounted cash flow rate return of 29%. Waste-based acetone-butanol production via fermentation deserves further attention in view of the attractive whey-based economics and the excellent potential of butanol as a fuel extender, especially for diesohol blending.

  16. Self-Associating Behavior of Acetone in Liquid Krypton.

    PubMed

    De Beuckeleer, Liene I; Herrebout, Wouter A

    2016-02-18

    Acetone molecules are inclined to self-associate through dipole-dipole interactions because of their large dipole moment. Infrared spectroscopy of compounds dissolved in liquid noble gases supported by high level ab initio calculations allows investigating the self-associating behavior and determining the thermodynamical properties. In this study, infrared spectra of various concentrations of acetone dissolved in liquid krypton are recorded at constant temperature. Overlapping monomer and dimer spectra are separated by analyzing the obtained data sets with numerical methods based on least-squares fitting. Although acetone is known to self-associate, only a few spectral features have been presented in literature before. In this study, the application of new numerical approaches succeeds in resolving overlapping spectra and allows observing isolated acetone dimer absorption bands for the complete mid infrared spectrum. By use of data sets of spectra recorded at temperatures between 134 and 142 K, the experimental standard dimerization enthalpy was determined to be -10.8 kJ mol(-1). MP2/aug-cc-pVDZ calculations predicted a stacked and planar dimer geometry of which the stacked geometry is more stable. Combining MP2 energies and single point corrections involving CCSD(T) calculations and complete basis set extrapolations based on the MP2/aug-cc-pVDZ equilibrium geometry lead to complexation energy of -28.4 kJ mol(-1) for the stacked geometry and -15.1 kJ mol(-1) for the planar geometry. The corresponding values for the complexation enthalpies in solution, obtained by combining these values with corrections for thermal and solvent influences are -13.7 and -5.8 kJ mol(-1). PMID:26805773

  17. PHYSIOLOGICALLY BASED PHARMACOKINEITC (PBPK) MODELING OF METABOLIC INHIBITION FOR INTERACTION BETWEEN TRICHLOROETHYLENE AND CHLOROFORM

    EPA Science Inventory

    Trichloroethylene (TCE) and chloroform (CHCl3) are two of the most common environmental contaminants found in water. PBPK models have been increasingly used to predict target dose in internal tissues from available environmental exposure concentrations. A closed inhalation (or g...

  18. Abiotic degradation rates for carbon tetrachloride and chloroform: Final report.

    SciTech Connect

    Amonette, James E.; Jeffers, Peter M.; Qafoku, Odeta; Russell, Colleen K.; Humphrys, Daniel R.; Wietsma, Thomas W.; Truex, Michael J.

    2012-12-01

    This report documents the objectives, technical approach, and progress made through FY 2012 on a project initiated in FY 2006 to help address uncertainties related to the rates of hydrolysis in groundwater for carbon tetrachloride (CT) and chloroform (CF). The project also sought to explore the possible effects of contact with minerals and sediment (i.e., heterogeneous hydrolysis) on these rates. We conducted 114 hydrolysis rate experiments in sealed vessels across a temperature range of 20-93 °C for periods as long as 6 years, and used the Arrhenius equation to estimate activation energies and calculate half-lives for typical Hanford groundwater conditions (temperature of 16 °C and pH of 7.75). We calculated a half-life of 630 years for hydrolysis for CT under these conditions and found that CT hydrolysis was unaffected by contact with sterilized, oxidized minerals or Hanford sediment within the sensitivity of our experiments. In contrast to CT, hydrolysis of CF was generally slower and very sensitive to pH due to the presence of both neutral and base-catalyzed hydrolysis pathways. We calculated a half-life of 3400 years for hydrolysis of CF in homogeneous solution at 16 °C and pH 7.75. Experiments in suspensions of Hanford sediment or smectite, the dominant clay mineral in Hanford sediment, equilibrated to an initial pH of 7.2, yielded calculated half-lives of 1700 years and 190 years, respectively, at 16 °C. Experiments with three other mineral phases at the same pH (muscovite mica, albite feldspar, and kaolinite) showed no change from the homogeneous solution results (i.e., a half-life of 3400 years). The strong influence of Hanford sediment on CF hydrolysis was attributed to the presence of smectite and its ability to adsorb protons, thereby buffering the solution pH at a higher level than would otherwise occur. The project also determined liquid-vapor partition coefficients for CT under the temperatures and pressures encountered in the sealed vessels that

  19. Acute Toxicity and Bioaccumulation of Chloroform to Four Species of Freshwater Fish

    SciTech Connect

    ,

    1980-08-01

    Acute toxicity of chloroform to four species of freshwater fish was studied in flow-through 96-hr toxicity tests. Chloroform is toxic to fish in the tens of parts per million, a concentration well above that which would be expected to be produced under normal power plant chlorination conditions. Investigations of acute toxicity of chloroform and the bioaccumulation of chlorinated compounds in tissues of fish revealed differences in tolerance levels and tissue accumulations. Mean 96-hr LC{sub 50}s for chloroform were 18 ppm for rainbow trout and bluegill, 51 ppm for largemouth bass and 75 ppm for channel catfish. Mortalities of bluegill and largemouth bass occurred during the first 4 hr of exposure while rainbow trout and channel catfish showed initial tolerance and mortalities occurred during the latter half of the 96-hr exposure. Rainbow trout had the highest level of chloroform tissue accumulation, 7 {micro}g/g tissue, catfish the second highest, 4 {micro}g/g tissue, followed by bluegill and largemouth bass which each accumulated about 3 {micro}g/g tissue. Accumulation of chloroform was less than one order of magnitude above water concentrations for all species.

  20. Influence of sexual dimorphism on pulmonary inflammatory response in adult mice exposed to chloroform.

    PubMed

    de Oliveira, Túlio Henrique Versiani; Campos, Keila Karine Duarte; Soares, Nícia Pedreira; Pena, Karina Braga; Lima, Wanderson Geraldo; Bezerra, Frank Silva

    2015-01-01

    Chloroform is an organic solvent used as an intermediate in the synthesis of various fluorocarbons. Despite its widespread use in industry and agriculture, exposure to chloroform can cause illnesses such as cancer, especially in the liver and kidneys. The aim of the study was to analyze the effects of chloroform on redox imbalance and pulmonary inflammatory response in adult C57BL/6 mice. Forty animals were divided into 4 groups (N = 10): female (FCG) and male (MCG) controls, and females (FEG) and males (MEG) exposed to chloroform (7.0 ppm) 3 times/d for 20 minutes for 5 days. Total and differential cell counts, oxidative damage analysis, and protein carbonyl and antioxidant enzyme catalase (CAT) activity measurements were performed. Morphometric analyses included alveolar area (Aa) and volume density of alveolar septa (Vv) measurements. Compared to FCG and MCG, inflammatory cell influx, oxidative damage to lipids and proteins, and CAT activity were higher in FEG and MEG, respectively. Oxidative damage and enzyme CAT activity were higher in FEG than in FCG. The Aa was higher in FEG and MEG than in FCG and MCG, respectively. The Vv was lower in FEG and MEG than in FCG and MCG, respectively. This study highlights the risks of occupational chloroform exposure at low concentrations and the intensity of oxidative damage related to gender. The results validate a model of acute exposure that provides cellular and biochemical data through short-term exposure to chloroform. PMID:25870144

  1. Improving the Adhesion of Au Thin Films Onto PMMA Substrates Using Chloroform

    NASA Astrophysics Data System (ADS)

    Wardwell, Courtney; Mo, Alan; Augustine, Brian; Hughes, Chris; DeVore, Thomas; James Madison University Team

    2013-03-01

    Conventional techniques such as O2 plasma treatment to improve Au thin film adhesion have resulted in limited success. In this study, the adhesion of 6 nm and 100 nm Au thin films onto 0.8 mm poly(methyl methacrylate) (PMMA) sheets was significantly improved when Au thin film samples were exposed to a saturated chloroform environment after metallization. The shear force required to remove the Au films was calculated by placing samples onto a polisher spinning at 150 rpm and using a spring loaded device to apply the force. Au thin samples were characterized through optical microscopy, atomic force microscopy (AFM) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). AFM and optical images show a roughening of the Au thin films after chloroform exposure. ATR-FTIR spectra indicate that residual chloroform solvent remains on the PMMA. Our research indicates chloroform may improve adhesion by relieving the stresses at the PMMA-Au interface. X-ray photoelectron spectroscopy (XPS) studies on chloroform pre-treated PMMA samples show residual solvent at the surface one-week after exposure. We have attributed this to a Lewis acid-base interaction between chloroform and the PMMA surface. We will report on the XPS data of post treated samples.

  2. Acetone and Acetaldehyde Exchange Above a Managed Temperate Mountain Grassland

    NASA Astrophysics Data System (ADS)

    Hörtnagl, L. J.; Bamberger, I.; Graus, M.; Ruuskanen, T.; Schnitzhofer, R.; Hansel, A.; Wohlfahrt, G.

    2011-12-01

    The exchange of acetone and acetaldehyde was measured above an intensively managed hay meadow in the Stubai Valley (Tyrol, Austria) during the growing seasons in 2008 and 2009. Half-hourly fluxes of both compounds were calculated by means of the virtual disjunct eddy covariance (vDEC) method by combining the 3-dimensional wind data from a sonic anemometer with the compound specific volume mixing ratios quantified with a proton-transfer-reaction mass spectrometer (PTR-MS). The cutting of the meadow resulted in the largest perturbation of the VOC exchange rates. Peak emissions for both VOC species were observed during and right after the cutting of the meadow, with rates of up to 12.1 and 10.1 nmol m-2 s-1 for acetaldehyde and acetone, respectively, reflecting the drying of the wounded plant material. During certain time periods, undisturbed by management events, both compounds exhibited a clear diurnal cycle. Emission rates of up to 3.7 nmol m-2 s-1 for acetaldehyde and 3.2 nmol m-2 s-1 for acetone were measured in October 2008, while a uptake of both compounds with rates of up to 1.8 and 2.1 nmol m-2 s-1, respectively, could be observed in May 2009, when also clear compensation points of 0.3 ppb for acetaldehyde and 1.0 ppb for acetone were observed. In an effort to explore the controls on observed exchange patterns, a simple and multiple linear regression analysis was conducted. A clear interconnection between VOC concentrations and VOC exchange could be seen only in May 2009, when concentration values alone explained 30.6% and 11.7% of the acetaldehyde and acetone flux variance, respectively. However, when trying to predict the observed exchange patterns of both VOC species in a multiple linear regression based on supporting environmental measurements - including air and soil temperature, soil water content and PAR among others - the analysis yielded unsatisfactory results, accounting for 10% and 4% of the observed acetaldehyde and acetone flux variance over both

  3. 21 CFR 184.1293 - Ethyl alcohol.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies are available from the National Academy Press, Box... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ethyl alcohol. 184.1293 Section 184.1293 Food and....1293 Ethyl alcohol. (a) Ethyl alcohol (ethanol) is the chemical C2H5OH. (b) The ingredient meets...

  4. 21 CFR 184.1293 - Ethyl alcohol.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... is incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies are... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ethyl alcohol. 184.1293 Section 184.1293 Food and... Substances Affirmed as GRAS § 184.1293 Ethyl alcohol. (a) Ethyl alcohol (ethanol) is the chemical C2H5OH....

  5. 21 CFR 184.1293 - Ethyl alcohol.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... is incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies are... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ethyl alcohol. 184.1293 Section 184.1293 Food and... Substances Affirmed as GRAS § 184.1293 Ethyl alcohol. (a) Ethyl alcohol (ethanol) is the chemical C2H5OH....

  6. 21 CFR 184.1293 - Ethyl alcohol.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... is incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies are... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ethyl alcohol. 184.1293 Section 184.1293 Food and... Substances Affirmed as GRAS § 184.1293 Ethyl alcohol. (a) Ethyl alcohol (ethanol) is the chemical C2H5OH....

  7. 21 CFR 184.1293 - Ethyl alcohol.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... is incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies are... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethyl alcohol. 184.1293 Section 184.1293 Food and... Substances Affirmed as GRAS § 184.1293 Ethyl alcohol. (a) Ethyl alcohol (ethanol) is the chemical C2H5OH....

  8. Acetone formation in the Vibrio family: a new pathway for bacterial leucine catabolism.

    PubMed

    Nemecek-Marshall, M; Wojciechowski, C; Wagner, W P; Fall, R

    1999-12-01

    There is current interest in biological sources of acetone, a volatile organic compound that impacts atmospheric chemistry. Here, we determined that leucine-dependent acetone formation is widespread in the Vibrionaceae. Sixteen Vibrio isolates, two Listonella species, and two Photobacterium angustum isolates produced acetone in the presence of L-leucine. Shewanella isolates produced much less acetone. Growth of Vibrio splendidus and P. angustum in a fermentor with controlled aeration revealed that acetone was produced after a lag in late logarithmic or stationary phase of growth, depending on the medium, and was not derived from acetoacetate by nonenzymatic decarboxylation in the medium. L-Leucine, but not D-leucine, was converted to acetone with a stoichiometry of approximately 0.61 mol of acetone per mol of L-leucine. Testing various potential leucine catabolites as precursors of acetone showed that only alpha-ketoisocaproate was efficiently converted by whole cells to acetone. Acetone production was blocked by a nitrogen atmosphere but not by electron transport inhibitors, suggesting that an oxygen-dependent reaction is required for leucine catabolism. Metabolic labeling with deuterated (isopropyl-d(7))-L-leucine revealed that the isopropyl carbons give rise to acetone with full retention of deuterium in each methyl group. These results suggest the operation of a new catabolic pathway for leucine in vibrios that is distinct from the 3-hydroxy-3-methylglutaryl-coenzyme A pathway seen in pseudomonads. PMID:10601206

  9. Hot spot formation of chloroform in forest soils caused pollution of groundwater

    NASA Astrophysics Data System (ADS)

    Jacobsen, Ole S.; Albers, Christian N.; Laier, Troels; Hunkeler, Daniel

    2015-04-01

    High concentration of chloroform in groundwater is usually attributed to anthropogenic input, but we have found that the groundwater beneath some pristine areas contained chloroform from 1 - 10 µg/L. Groundwater containing chloroform that exceeds 1 µg/L could not be used for drinking water according to Danish regulations. The strict demands on groundwater quality may have to be taken into account when decisions are made regarding the change of land use in order to protect major recharge areas from pollution with nitrate and pesticides resulting from high-yield agriculture production. The terrestrial environment and especially hot spots in forest soils seem to be important contributors to apparent pollution of groundwater with chloroform. We performed a field study to investigate concentration and fluxes of chloroform to the groundwater from in four coniferous forests in order to increase knowledge on the hot spot formation and fate of natural chloroform. We investigated four stations over a period of several years in order to measure the net-formation of chloroform. Field measurements soil air concentrations of chloroform were monitored in five soil profiles down to the groundwater table. Meteorological data were recorded at all stations In the hotspots up to 120 ppbv was found in soil air under the spruce forest, to be compared to an ambient atmospheric concentration of 0.02 ppbv. The concentration of chloroform in soil air showed seasonal variation with a maximum in August-September. The chloroform concentration decreased with depth in all profiles during the summer half-year to about 20 % of concentration in the production layer. However, the concentration is still high enough to give an equilibrium concentration in the upper groundwater of 1-10 µg/L. Stable carbon isotopic analyses of chloroform from the uppermost groundwater in different parts of the forests and from soil water showed values from δ13C = -13 ‰ to -27 ‰, corresponding to the ratio in

  10. Hydrogenation of ethyl 5-cyano-2-oximinovalerate

    SciTech Connect

    Klabunovskii, E.I.; Levitina, E.S.; Kaigorodova, L.N.; Godunova, L.F.; Gogoladze, D.D.; Karpeiskaya, E.I.; Novikova, S.A.

    1987-03-10

    Hydrogenation of ethyl 5-cyano-2-oximinovalerate in acetic anhydride at atmospheric pressure in the presence of strong base leads to a quantitative yield of the ethyl ester of ..cap alpha..,eta-diacetyllysine. Selective reduction of the cyano and oximino groups in ethyl 5-cyano-2-oximinovalerate has been shown in the presence of powdered Ni, Cu-Ni, and LaNi/sub 5/H/sub 6.6/ catalysts. Hydrogenation of ethyl 5-cyano-2-oximinovalerate on Raney Ni at atmospheric pressure in dioxan with addition of acetic anhydride leads to a 50% yield of diacetyllysine.

  11. Insights into Acetone Photochemistry on Rutile TiO2(110). 1. Off-Normal CH3 Ejection from Acetone Diolate.

    SciTech Connect

    Petrik, Nikolay G.; Henderson, Michael A.; Kimmel, Gregory A.

    2015-06-04

    Thermal- and photon-stimulated reactions of acetone co-adsorbed with oxygen on rutile TiO2(110) surface are studied with infrared reflection-adsorption spectroscopy (IRAS) combined with temperature programmed desorption and angle-resolved photon stimulated desorption. IRAS results show that n2-acetone diolate ((CH3)2COO) is produced via thermally-activated reactions between the chemisorbed oxygen with co-adsorbed acetone. Formation of acetone diolate is also consistent with 18O / 16O isotopic exchange experiments. During UV irradiation at 30 K, CH3 radicals are ejected from the acetone diolate with a distribution that is peaked at .-. +- 66 degrees from the surface normal along the azimuth (i.e. perpendicular to the rows of bridging oxygen and Ti5c ions). This distribution is also consistent with the orientation of the C–CH3 bonds in the n2-acetone diolate on TiO2(110). The acetone diolate peaks disappear from the IRAS spectra after UV irradiation and new peaks are observed and associated with n2-acetate. The data presented here demonstrate direct signatures of the proposed earlier 2-step mechanism for acetone photooxidation on TiO2(110)

  12. Enhancing acetone biosynthesis and acetone-butanol-ethanol fermentation performance by co-culturing Clostridium acetobutylicum/Saccharomyces cerevisiae integrated with exogenous acetate addition.

    PubMed

    Luo, Hongzhen; Ge, Laibing; Zhang, Jingshu; Ding, Jian; Chen, Rui; Shi, Zhongping

    2016-01-01

    Acetone is the major by-product in ABE fermentations, most researches focused on increasing butanol/acetone ratio by decreasing acetone biosynthesis. However, economics of ABE fermentation industry strongly relies on evaluating acetone as a valuable platform chemical. Therefore, a novel ABE fermentation strategy focusing on bio-acetone production by co-culturing Clostridium acetobutylicum/Saccharomyces cerevisiae with exogenous acetate addition was proposed. Experimental and theoretical analysis revealed the strategy could, enhance C. acetobutylicum survival oriented amino acids assimilation in the cells; control NADH regeneration rate at moderately lower level to enhance acetone synthesis but without sacrificing butanol production; enhance the utilization ability of C. acetobutylicum on glucose and direct most of extra consumed glucose into acetone/butanol synthesis routes. By implementing the strategy using synthetic or acetate fermentative supernatant, acetone concentrations increased to 8.27-8.55g/L from 5.86g/L of the control, while butanol concentrations also elevated to the higher levels of 13.91-14.23g/L from 11.63g/L simultaneously. PMID:26476171

  13. Methyl Chloroform Elimination from the Production of Space Shuttle Sold Rocket Motors

    NASA Technical Reports Server (NTRS)

    Golde, Rick P.; Burt, Rick; Key, Leigh

    1997-01-01

    Thiokol Space Operations manufactures the Reusable Solid Rocket Motors used to launch America's fleet of Space Shuttles. In 1989, Thiokol used more than 1.4 Mlb of methyl chloroform to produce rocket motors. The ban placed by the Environmental Protection Agency on the sale of methyl chloroform had a significant effect on future Reusable Solid Rocket Motor production. As a result, changes in the materials and processes became necessary. A multiphased plan was established by Thiokol in partnership with NASA's Marshall Space Flight Center to eliminate the use of methyl chloroform in the Reusable Solid Rocket Motor production process. Because of the extensive scope of this effort, the plan was phased to target the elimination of the majority of methyl chloroform use (90 percent) by January 1, 1996, the 3 Environmental Protection Agency deadline. Referred to as Phase I, this effort includes the elimination of two large vapor degreasers, grease diluent processes, and propellant tooling handcleaning using methyl chloroform. Meanwhile, a request was made for an essential use exemption to allow the continued use of the remaining 10 percent of methyl chloroform after the 1996 deadline, while total elimination was pursued for this final, critical phase (Phase II). This paper provides an update to three previous presentations prepared for the 1993, 1994, and 1995 CFC/Halon Alternative Conferences, and will outline the overall Ozone Depleting Compounds Elimination Program from the initial phases through the final testing and implementation phases, including facility and equipment development. Processes and materials to be discussed include low-pressure aqueous wash systems, high-pressure water blast systems- environmental shipping containers, aqueous and semi-aqueous cleaning solutions, and bond integrity and inspection criteria. Progress toward completion of facility implementation and lessons learned during the scope of the program, as well as the current development efforts

  14. Preserving ground water samples with hydrochloric acid does not result in the formation of chloroform

    USGS Publications Warehouse

    Squillace, Paul J.; Pankow, James F.; Barbash, Jack E.; Price, Curtis V.; Zogorski, John S.

    1999-01-01

    Water samples collected for the determination of volatile organic compounds (VOCs) are often preserved with hydrochloric acid (HCl) to inhibit the biotransformation of the analytes of interest until the chemical analyses can he performed. However, it is theoretically possible that residual free chlorine in the HCl can react with dissolved organic carbon (DOC) to form chloroform via the haloform reaction. Analyses of 1501 ground water samples preserved with HCl from the U.S. Geological Survey's National Water-Quality Assessment Program indicate that chloroform was the most commonly detected VOC among 60 VOCs monitored. The DOC concentrations were not significantly larger in samples with detectable chloroform than in those with no delectable chloroform, nor was there any correlation between the concentrations of chloroform and DOC. Furthermore, chloroform was detected more frequently in shallow ground water in urban areas (28.5% of the wells sampled) than in agricultural areas (1.6% of the wells sampled), which indicates that its detection was more related to urban land-use activities than to sample acidification. These data provide strong evidence that acidification with HCl does not lead to the production of significant amounts of chloroform in ground water samples. To verify these results, an acidification study was designed to measure the concentrations of all trihalomethanes (THMs) that can form as a result of HCl preservation in ground water samples and to determine if ascorbic acid (C6H8O6) could inhibit this reaction if it did occur. This study showed that no THMs were formed as a result of HCl acidification, and that ascorbic acid had no discernible effect on the concentrations of THMs measured.

  15. Uncertainties in Biogenic Sources and Sinks and Their Relevance for the Global Acetone Budget

    NASA Astrophysics Data System (ADS)

    Brewer, J.; Fischer, E. V.; Ravishankara, A. R.; Bishop, M.

    2015-12-01

    Acetone is one of the most abundant carbonyl compounds in the atmosphere, and a major source of HOx radicals in the upper troposphere. Thus, understanding the global budget of acetone is essential to understanding global oxidation capacity. Significant uncertainties remain regarding the flux of acetone out of and into the biosphere. Crucially unconstrained processes include dry deposition, fluxes of acetone into and out of the ocean, direct emissions of acetone from the terrestrial biosphere, and direct emissions of secondary sources of acetone such as the oxidation of monoterpenes from the terrestrial biosphere. We have performed an elementary effects sensitivity analysis of the GEOS-Chem global 3-D CTM (version 10-01, www.geos-chem.org) for the global atmospheric distribution of acetone using the Morris method. This method provides a ranking of both the comparative direct importance, as well as non-linear effects and interactions of the tested input factor uncertainties, at a relatively low computational cost. The sensitivity analysis was bounded using literature minima and maxima for five sources of uncertainty related to specific biogenic sources and sinks. Preliminary results suggest that the uncertainties with the largest impact on acetone concentration are the uncertainties in direct acetone emissions from the terrestrial biosphere and uncertainties in the concentration of acetone in the ocean mixed layer.

  16. 27 CFR 21.108 - Ethyl ether.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Ethyl ether. 21.108 Section 21.108 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.108 Ethyl ether. (a) Odor. Characteristic odor....

  17. 21 CFR 573.420 - Ethyl cellulose.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

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

  18. 21 CFR 573.420 - Ethyl cellulose.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

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

  19. 21 CFR 573.420 - Ethyl cellulose.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

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

  20. 27 CFR 21.108 - Ethyl ether.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Ethyl ether. 21.108 Section 21.108 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT....108 Ethyl ether. (a) Odor. Characteristic odor. (b) Specific gravity at 15.56 °/15.56 °C. Not...

  1. 21 CFR 172.868 - Ethyl cellulose.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ethyl cellulose. 172.868 Section 172.868 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.868 Ethyl...

  2. 21 CFR 172.868 - Ethyl cellulose.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ethyl cellulose. 172.868 Section 172.868 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.868 Ethyl...

  3. 27 CFR 21.108 - Ethyl ether.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Ethyl ether. 21.108 Section 21.108 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.108 Ethyl ether. (a) Odor. Characteristic odor....

  4. 21 CFR 173.228 - Ethyl acetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... the specifications of the Food Chemicals Codex, 1 (Ethyl Acetate; p. 372, 3d Ed., 1981), which are... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethyl acetate. 173.228 Section 173.228 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR...

  5. 27 CFR 21.108 - Ethyl ether.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Ethyl ether. 21.108 Section 21.108 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.108 Ethyl ether. (a) Odor. Characteristic odor....

  6. 27 CFR 21.108 - Ethyl ether.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Ethyl ether. 21.108 Section 21.108 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.108 Ethyl ether. (a) Odor. Characteristic odor....

  7. COMPARISON OF HIGHLY-FLUORINATED CHLOROFORMATES AS DIRECT AQUEOUS SAMPLE DERIVATIZING AGENTS FOR HYDROPHILIC ANALYTES AND DRINKING WATER DISINFECTION BY-PRODUCTS

    EPA Science Inventory

    Four highly-fluorinated alkyl and aryl chloroformates, including 2,2,3,3,4,4,5,5-octafluoro-1-pentyl chloroformate (OFPCF), 2,3,4,5,6-pentafluorobenzyl chloroformate (PFBCF), 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-1-octyl chloroformate (TDFOCF) and 2-(2,3,4,5,6-pentafluorophenox...

  8. Characterization of hot spots for natural chloroform formation: Relevance for groundwater quality

    NASA Astrophysics Data System (ADS)

    Jacobsen, Ole S.; Albers, Christian N.; Laier, Troels

    2015-04-01

    Chloroform soil hot spot may deteriorate groundwater quality and may even result in chloroform concentration exceeding the Danish maximum limit of 1 µg/L in groundwater for potable use. In order to characterize the soil properties important for the chloroform production, various ecosystems were examined with respect to soil air chloroform and soil organic matter type and content. Coniferous forest areas, responsible for highest chloroform concentrations, were examined on widely different scales from km to cm scale. Furthermore, regular soil gas measurements including chloroform were performed during 4 seasons at various depths, together with various meteorological measurements and soil temperature recordings. Laboratory incubation experiments were also performed on undisturbed soil samples in order to examine the role of various microbiota, fungi and bacteria. To identify hot spots responsible for the natural contamination we have measured the production of chloroform in the upper soil from different terrestrial systems. Field measurements of chloroform in top soil air were used as production indicators. The production was however not evenly distributed at any scale. The ecosystems seem to have quite different net-productions of chloroform from very low in grassland to very high in some coniferous forests. Within the forest ecosystem we found large variation in chloroform concentrations depending on vegetation. In beech forest we found the lowest values, somewhat higher in an open pine forest, but the highest concentrations were detected in spruce forest without any vegetation beneath. Within this ecotype, it appeared that the variation was also large; hot spots with 2-4 decades higher production than the surrounding area. These hot spots were not in any way visually different from the surroundings and were of variable size from 3 to 20 meters in diameter. Besides this, measurements within a seemingly homogenous hot spot showed that there was still high

  9. Catalytic oxidation of dichloromethane, chloroform, and their binary mixtures over a platinum alumina catalyst

    SciTech Connect

    Papenmeier, D.M.; Rossin, J.A. . Gunpowder Branch)

    1994-12-01

    The complete catalytic oxidation of dichloromethane, chloroform, and their binary mixtures was examined over a 3% Pt/[kappa]-[delta] Al[sub 2]O[sub 3] catalyst at temperature between 300 and 400 C using a fixed bed catalytic reactor. The oxidation of chloroform and dichloromethane as pure compounds was nonlinear in the concentration of chloromethane and zeroth order in the concentration of oxygen. HCl, formed during the oxidation of each chloromethane, decreased the reaction rate. Kinetic rate expressions were developed to described the oxidation of dichloromethane and chloroform as pure compounds. These expressions were derived by assuming that the reaction occurred via adsorption and decomposition of the chloromethane into an oxygen covered platinum surface, with the reaction being inhibited by the presence of HCl. From the results of the pure compound studies, reaction rate expressions were developed to describe the oxidation of dichloromethane/chloroform mixtures. The resulting reaction rate expressions accurately predicted the catalyst's performance during the oxidation of dichloromethane/chloroform mixtures over a wide range of conditions.

  10. Studies on tropane alkaloid extraction by volatile organic solvents: dichloromethane vs. chloroform.

    PubMed

    El Jaber-Vazdekis, Nabil; Gutierrez-Nicolas, Fátima; Ravelo, Angel G; Zárate, Rafael

    2006-01-01

    In order to investigate the production of tropane alkaloids by hairy roots of Atropa baetica, transgenic for the gene h6h encoding the enzyme hyoscyamine 6beta-hydroxylase, solvent extraction with chloroform and with dichloromethane of the metabolites present in the liquid medium and in the root tissue was compared. The extraction of scopolamine from the liquid medium was equally effective with either solvent, giving maximum values of around 850 microg/flask. For the roots, three different extraction methods were employed: A, employing chloroform:methanol: (25%) ammonia (15:5:1) for initial extraction, followed by treatment with sulfuric acid and ammonia, and using chloroform for the final extraction and washes; B, as A but using dichloromethane for extraction and washes; and C, as B but substituting chloroform for dichloromethane in the extraction cocktail. Scopolamine was the most abundant metabolite (present in amounts of 3250-3525 microg/g dry weight) and presented similar extraction efficiencies with all of the extraction methods employed. The highest amounts of hyoscyamine and the intermediate 6beta-hydxoxyhyoscyamine were present on day 31 (800 and 975 microg/g dry weight, respectively) and no statistical differences between the three extraction methods employed were detected. This study confirms that, for the extraction of tropane alkaloids, dichloromethane can replace the commonly employed chloroform, the use of which incurs major health, security and regulation problems. PMID:16634287

  11. Formation and inhibition of ethyl glucuronide and ethyl sulfate.

    PubMed

    Stachel, Nicole; Skopp, Gisela

    2016-08-01

    Ethyl glucuronide (EtG) und ethyl sulfate (EtS) are widely accepted biomarkers in forensic and clinical settings. Even though, levels of EtG and EtS in blood and urine increase with increasing doses of alcohol, a high inter-individual variability in their production has been noticed. Therefore, we investigated the influence of dietary plant phenols on the formation of EtG and EtS and tentatively estimated the magnitude of in vivo inhibitory interactions from our in vitro results. To address these issues, formation of EtS and EtG was investigated using recombinant glucuronosyl- and sulfotransferases as well as human liver microsomes and liver cytosol. After respective kinetics had been established, inhibition experiments using quercetin, kaempferol and resveratrol were performed. These polyphenols are subject to extensive glucuronidation and/or sulfonation. EtG and EtS were determined by LC-MS/MS following solid phase extraction for EtG due to severe matrix effects and by direct injection for EtS. All enzymes investigated were involved in the conjugation of ethanol. Maximal EtG and EtS formation rates were observed with HLM and SULT1A1, respectively. All kinetics could best be described by Michaelis-Menten kinetics. Resveratrol was a competitive inhibitor of UGT1A1, UGT1A9 and HLM; quercetin and kaempferol were inhibitors of all transferases under investigation except UGT2B15. Findings for quercetin with regard to UGT2B7 and SULT2A1 and for kaempferol with regard to SULT1E1 and SULT2A1 suggested a mechanism based inhibition. Competitive inhibition of the glucuronidation and sulfonation of ethanol was estimated as weak to negligible and as moderate to weak, respectively. Beside the known polymorphisms of the transferases involved in EtG and EtS formation, prediction of the inhibitory potential indicates that polyphenols may contribute to the variable formation rate of EtG and EtS. PMID:26829336

  12. Osteocompatibility evaluation of poly(glycine ethyl ester-co-alanine ethyl ester)phosphazene with honeycomb-patterned surface topography.

    PubMed

    Duan, Shun; Yang, Xiaoping; Mao, Jifu; Qi, Bing; Cai, Qing; Shen, Hong; Yang, Fei; Deng, Xuliang; Wang, Shenguo

    2013-02-01

    Biodegradable amino acid ester-substituted polyphosphazenes are unique biomaterials for tissue engineering. Considering the surface properties as topography and chemical composition having vital roles in regulating cellular response, in this study, a kind of micropatterned polyphosphazene films were prepared and subjected to osteoblasts culture. Briefly, poly(glycine ethyl ester-co-alanine ethyl ester)phosphazene (PGAP) was synthesized, and its solution in chloroform was cast under high (80%) or low (20%) environmental humidity. Honeycomb-patterned or flat PGAP films were resulted. By analyzing with scanning electron microscope, atomic force microscope, X-ray photoelectron spectroscope, and water contact angle measurement, the honeycomb-patterned PGAP films demonstrated higher surface roughness, phosphorous and nitrogen content, and hydrophilicity than the flat one. Although the initial cell attachment and proliferation on PGAP films were inferior to those on conventional poly(lactic-co-glycolic acid) films, P-containing PGAP was a sort of bone-binding bioactive polymer. With these alternations, honeycomb-patterned PGAP films had accordingly enhanced protein adsorption and apatite deposition in simulated body fluid and showed great advantages in promoting osteogenous differentiation. The results suggested a potential way to make polyphosphazenes as good choices for bone tissue regeneration by increasing their surface roughness and phosphorous content. PMID:22733644

  13. Photoinduced charge transfer and acetone sensitivity of single-walled carbon nanotube-titanium dioxide hybrids.

    PubMed

    Ding, Mengning; Sorescu, Dan C; Star, Alexander

    2013-06-19

    The unique physical and chemical properties of single-walled carbon nanotubes (SWNTs) make them ideal building blocks for the construction of hybrid nanostructures. In addition to increasing the material complexity and functionality, SWNTs can probe the interfacial processes in the hybrid system. In this work, SWNT-TiO2 core/shell hybrid nanostructures were found to exhibit unique electrical behavior in response to UV illumination and acetone vapors. By experimental and theoretical studies of UV and acetone sensitivities of different SWNT-TiO2 hybrid systems, we established a fundamental understanding on the interfacial charge transfer between photoexcited TiO2 and SWNTs as well as the mechanism of acetone sensing. We further demonstrated a practical application of photoinduced acetone sensitivity by fabricating a microsized room temperature acetone sensor that showed fast, linear, and reversible detection of acetone vapors with concentrations in few parts per million range. PMID:23734594

  14. Fate of acetone in an outdoor model stream in southern Mississippi, U.S.A.

    USGS Publications Warehouse

    Rathbun, R.E.; Stephens, D.W.; Shultz, D.J.; Tai, D.Y.

    1988-01-01

    The fate of acetone in water was investigated in an outdoor model stream located in southern Mississippi, U.S.A. Acetone was injected continuously for 32 days resulting in small milligram-perliter concentrations in the stream. Rhodamine-WT dye was injected at the beginning and at the end of the study to determine the time-of-travel and dispersion characteristics of the stream. A 12-h injection of t-butyl alcohol (TBA) was used to determine the volatilization characteristics of the stream. Volatilization controlled the acetone concentration in the stream. Significant bacterial degradation of acetone did not occur, contrary to expectations based on previous laboratory studies. Attempts to induce degradation of the acetone by injecting glucose and a nutrient solution containing bacteria acclimated to acetone were unsuccessful. Possible explanations for the lack of bacterial degradation included a nitrate limitation and a limited residence time in the stream system. ?? 1988.

  15. Mechanism of chloroform-induced renal toxicity: Non-involvement of hepatic cytochrome P450-dependent metabolism

    SciTech Connect

    Fang Cheng; Behr, Melissa; Xie Fang; Lu Shijun; Doret, Meghan; Luo Hongxiu; Yang Weizhu; Aldous, Kenneth; Ding Xinxin; Gu Jun

    2008-02-15

    Chloroform causes hepatic and renal toxicity in a number of species. In vitro studies have indicated that chloroform can be metabolized by P450 enzymes in the kidney to nephrotoxic intermediate, although direct in vivo evidence for the role of renal P450 in the nephrotoxicity has not been reported. This study was to determine whether chloroform renal toxicity persists in a mouse model with a liver-specific deletion of the P450 reductase (Cpr) gene (liver-Cpr-null). Chloroform-induced renal toxicity and chloroform tissue levels were compared between the liver-Cpr-null and wild-type mice at 24 h following differing doses of chloroform. At a chloroform dose of 150 mg/kg, the levels of blood urea nitrogen (BUN) were five times higher in the exposed group than in the vehicle-treated one for the liver-Cpr-null mice, but they were only slightly higher in the exposed group than in the vehicle-treated group for the wild-type mice. Severe lesions were found in the kidney of the liver-Cpr-null mice, while only mild lesions were found in the wild-type mice. At a chloroform dose of 300 mg/kg, severe kidney lesions were observed in both strains, yet the BUN levels were still higher in the liver-Cpr-null than in the wild-type mice. Higher chloroform levels were found in the tissues of the liver-Cpr-null mice. These findings indicated that loss of hepatic P450-dependent chloroform metabolism does not protect against chloroform-induced renal toxicity, suggesting that renal P450 enzymes play an essential role in chloroform renal toxicity.

  16. Purification and Characterization of the Acetone Carboxylase of Cupriavidus metallidurans Strain CH34

    PubMed Central

    Rosier, Caroline; Leys, Natalie; Henoumont, Céline; Mergeay, Max

    2012-01-01

    Acetone carboxylase (Acx) is a key enzyme involved in the biodegradation of acetone by bacteria. Except for the Helicobacteraceae family, genome analyses revealed that bacteria that possess an Acx, such as Cupriavidus metallidurans strain CH34, are associated with soil. The Acx of CH34 forms the heterohexameric complex α2β2γ2 and can carboxylate only acetone and 2-butanone in an ATP-dependent reaction to acetoacetate and 3-keto-2-methylbutyrate, respectively. PMID:22492439

  17. Purification and characterization of the acetone carboxylase of Cupriavidus metallidurans strain CH34.

    PubMed

    Rosier, Caroline; Leys, Natalie; Henoumont, Céline; Mergeay, Max; Wattiez, Ruddy

    2012-06-01

    Acetone carboxylase (Acx) is a key enzyme involved in the biodegradation of acetone by bacteria. Except for the Helicobacteraceae family, genome analyses revealed that bacteria that possess an Acx, such as Cupriavidus metallidurans strain CH34, are associated with soil. The Acx of CH34 forms the heterohexameric complex α(2)β(2)γ(2) and can carboxylate only acetone and 2-butanone in an ATP-dependent reaction to acetoacetate and 3-keto-2-methylbutyrate, respectively. PMID:22492439

  18. Reduction of chloroform formation potential of humic acid by sonolysis and ultraviolet irradiation.

    PubMed

    Naffrechoux, E; Combet, E; Fanget, B; Petrier, C

    2003-04-01

    This study is concerned with the changes of chloroform formation potential during the reaction of humic acid (HA) and sodium hypochlorite caused by different oxidative pretreatments: ultraviolet (UV) irradiation, ultrasonic (US) irradiation or combined UV-US irradiations. The UV and US decomposition of a reagent HA in water was investigated. The characterization of the oxidized HA sample by UV absorptiometry, synchronous fluorescence spectroscopy and size exclusion chromatography points a synergetic effect of the combined process. The values of the chlorine demand and chloroform formation potential were conventionally determined after a 96 h reaction at neutral pH. It was found that all applied processes decreased the concentration of chloroform but the highest decrease was observed for the UV-US treatment. PMID:12697238

  19. Predictors of personal air concentrations of chloroform among US adults in NHANES 1999-2000.

    PubMed

    Riederer, Anne M; Bartell, Scott M; Ryan, P Barry

    2009-03-01

    Volunteer studies suggest that showering/bathing with chlorinated tap water contributes to daily chloroform inhalation exposure for the majority of US adults. We used data from the 1999-2000 US National Health and Nutrition Examination Survey (NHANES) and weighted multiple linear regression to test the hypothesis that personal exposure microevents such as showering or spending time at a swimming pool would be significantly associated with chloroform levels in 2-3 day personal air samples. The NHANES data show that eight of 10 US adults are exposed to detectable levels of chloroform. Median (1.13 microg/m(3)), upper percentile (95th, 12.05 microg/m(3)), and cancer risk estimates were similar to those from recent US regional studies. Significant predictors of log personal air chloroform in our model (R(2)=0.34) included age, chloroform concentrations in home tap water, having no windows open at home during the sampling period, visiting a swimming pool during the sampling period, living in a mobile home/trailer or apartment versus living in a single family (detached) home, and being Non-Hispanic Black versus Non-Hispanic White, although the race/ethnicity estimates appear influenced by several outlying observations. Reported showering activity was not a significant predictor of personal air chloroform, possibly due to the wording of the NHANES shower question. The NHANES measurements likely underestimate true inhalation exposures since subjects did not wear sampling badges while showering or swimming, and because of potential undersampling by the passive monitors. Research is needed to quantify the potential difference. PMID:18335002

  20. Evaluation of the inhibitory effects of chloroform on ortho-chlorophenol- and chloroethene-dechlorinating Desulfitobacterium strains

    PubMed Central

    2013-01-01

    Organohalide-respiring Desulfitobacterium strains are believed to play an important role in the bioremediation and natural attenuation of chlorinated aliphatic and aromatic hydrocarbons. However, several studies have reported that chloroform significantly inhibits microbial reductive dechlorination of chloroethene. In this study, we examined the effect of chloroform on several Desulfitobacterium strains, including ortho-chlorophenol-dechlorinating Desulfitobacterium dehalogenans JW/IU-1 and Desulfitobacterium hafniense DCB-2, and also the chloroethene-dechlorinating strain D. hafniense TCE1. In medium containing 3-chloro-4-hydroxyphenylacetate as an electron acceptor, chloroform inhibited the growth of strains JW/IU-1 and DCB-2. Although chloroform did not directly inhibit dechlorination of 3-chloro-4-hydroxyphenylacetate by resting cells, cells cultivated with chloroform showed decreased dechlorination activity. Moreover, transcription of the gene encoding the reductive dehalogenase CprA decreased significantly in cells cultivated with chloroform. These results indicate that chloroform inhibits the growth and dechlorination activity of strains JW/IU-1 and DCB-2 via inhibition of cprA transcription. In contrast, cultivation of strain TCE1 in the presence of chloroform gave rise to a PceA reductive dehalogenase gene-deletion variant of strain TCE1; a similar phenomenon was observed in our previous study of chloroethene-dechlorinating D. hafniense strain Y51. Our results suggest that chloroform extensively inhibits the dechlorination activity of Desulfitobacterium strains, and that the inhibitory mechanism appears to differ between ortho-chlorophenol dechlorinators and chloroethene dechlorinators. PMID:23705686

  1. Fabrication of a SnO2-Based Acetone Gas Sensor Enhanced by Molecular Imprinting

    PubMed Central

    Tan, Wenhu; Ruan, Xiaofan; Yu, Qiuxiang; Yu, Zetai; Huang, Xintang

    2015-01-01

    This work presents a new route to design a highly sensitive SnO2–based sensor for acetone gas enhanced by the molecular imprinting technique. Unassisted and acetone-assisted thermal synthesis methods are used to synthesis SnO2 nanomaterials. The prepared SnO2 nanomaterials have been characterized by X-ray powder diffraction, scanning electron microscopy and N2 adsorption−desorption. Four types of SnO2 films were obtained by mixing pure deionized water and liquid acetone with the two types of as-prepared powders, respectively. The acetone gas sensing properties of sensors coated by these films were evaluated. Testing results reveal that the sensor coated by the film fabricated by mixing liquid acetone with the SnO2 nanomaterial synthesized by the acetone-assisted thermal method exhibits the best acetone gas sensing performance. The sensor is optimized for the smooth adsorption and desorption of acetone gas thanks to the participation of acetone both in the procedure of synthesis of the SnO2 nanomaterial and the device fabrication, which results in a distinct response–recovery behavior. PMID:25549174

  2. Modeling the interaction of ozone with chloroform and bromoform under conditions close to stratospheric

    NASA Astrophysics Data System (ADS)

    Strokova, N. E.; Yagodovskaya, T. V.; Savilov, S. V.; Lukhovitskaya, E. E.; Vasil'ev, E. S.; Morozov, I. I.; Lunin, V. V.

    2013-02-01

    The reactions of ozone with chloroform and bromoform are studied using a flow gas discharge vacuum unit under conditions close to stratospheric (temperature range, 77-250 K; pressure, 10-3-0.1 Torr in the presence of nitrate ice). It is shown that the reaction with bromoform begins at 160 K; the reaction with chloroform, at 190 K. The reaction products are chlorine and bromine oxides of different composition, identified by low-temperature FTIR spectroscopy. The presence of nitrate ice raises the temperature of reaction onset to 210 K.

  3. Mechanistic insights into the formation of chloroform from natural organic matter using stable carbon isotope analysis

    NASA Astrophysics Data System (ADS)

    Breider, Florian; Hunkeler, Daniel

    2014-01-01

    Chloroform can be naturally formed in terrestrial environments (e.g. forest soils, peatland) by chlorination of natural organic matter (NOM). Recently, it was demonstrated that natural and anthropogenic chloroform have a distinctly different carbon isotope signature that makes it possible to identify its origin in soil and groundwater. In order to evaluate the contribution of different functional groups to chloroform production and factors controlling the isotopic composition of chloroform, carbon isotope trends during chlorination of model compounds, soil organic matter (SOM) and humic acids were evaluated, and apparent kinetic isotope effects (AKIEs) quantified. Phenol and propanone were selected as model compounds representing common functional groups in NOM. Chlorination was induced by hypochlorous acid to mimic natural chlorination. The pH ranged between 4 and 8 to cover typical soil conditions. For each model compound and pH, different AKIEs were observed. For phenol, the AKIE was normal at pH 4 (1.0156 ± 0.0012) and inverse at pH 8 (0.9900 ± 0.0007). For 2-propoanol, an opposite pH dependence was observed with an inverse AKIE at pH 4 (0.9935 ± 0.0007) and a normal AKIE at pH 8 (1.0189 ± 0.0016). The variations of the AKIE values suggest that the rate-limiting step of the reaction is either the re-hybridization of the carbon atom involved in chloroform formation or the hydrolysis of trichloroacetyl intermediates depending on the nature of functional group and pH. The chloroform formation from humic acid and SOM gives rise to small isotope variations. A comparison of the isotopic trends of chloroform formed from humic acid and SOM with those found for the model compounds suggest that opposed AKIE associated with the chlorination of phenolic and ketone moieties of NOM partly compensate each other during chlorination of NOM indicating that different types of functional groups contribute to chloroform formation.

  4. Acaricidal activity of four fractions and octadecanoic acid-tetrahydrofuran-3,4-diyl ester isolated from chloroform extracts of neem (Azadirachta indica) oil against Sarcoptes scabiei var. cuniculi larvae in vitro.

    PubMed

    Du, Yong-Hua; Li, Jin-Liang; Jia, Ren-Yong; Yin, Zhong-Qiong; Li, Xu-Ting; Lv, Cheng; Ye, Gang; Zhang, Li; Zhang, Yu-Qun

    2009-07-01

    Four fractions obtained from chloroform extracts of neem (Azadirachta indica) oil by column chromatography were investigated for acaricidal activity against Sarcoptes scabiei var. cuniculi larvae in vitro. Octadecanoic acid-tetrahydrofuran-3,4-diyl ester was isolated from an active fraction of the chloroform extract and its toxicity against S. scabiei larvae was tested in vitro. A complementary log-log model was used to analyse the toxicity data. Activity was found in the third fraction, with 100% corrected mortality after 4.5 h of exposure at a concentration of 200 mg ml(-1). This fraction was repeatedly re-crystallised in acetone to yield a white amorphous powder, identified as octadecanoic acid-tetrahydrofuran-3,4-diyl ester, with a median lethal concentration (LC(50)) of 0.1 mg ml(-1) at 24 h post-treatment. The median lethal time (LT(50)) for this compound was 15.3 h at a concentration of 7.5 mg ml(-1). PMID:19443124

  5. System-level modeling of acetone-butanol-ethanol fermentation.

    PubMed

    Liao, Chen; Seo, Seung-Oh; Lu, Ting

    2016-05-01

    Acetone-butanol-ethanol (ABE) fermentation is a metabolic process of clostridia that produces bio-based solvents including butanol. It is enabled by an underlying metabolic reaction network and modulated by cellular gene regulation and environmental cues. Mathematical modeling has served as a valuable strategy to facilitate the understanding, characterization and optimization of this process. In this review, we highlight recent advances in system-level, quantitative modeling of ABE fermentation. We begin with an overview of integrative processes underlying the fermentation. Next we survey modeling efforts including early simple models, models with a systematic metabolic description, and those incorporating metabolism through simple gene regulation. Particular focus is given to a recent system-level model that integrates the metabolic reactions, gene regulation and environmental cues. We conclude by discussing the remaining challenges and future directions towards predictive understanding of ABE fermentation. PMID:27020410

  6. Ethyl cellulose microcapsules for protecting and controlled release of folic acid.

    PubMed

    Prasertmanakit, Satit; Praphairaksit, Nalena; Chiangthong, Worawadee; Muangsin, Nongnuj

    2009-01-01

    Ethyl cellulose microcapsules were developed for use as a drug-delivery device for protecting folic acid from release and degradation in the undesirable environmental conditions of the stomach, whilst allowing its release in the intestinal tract to make it available for absorption. The controlled release folic acid-loaded ethyl cellulose microcapsules were prepared by oil-in-oil emulsion solvent evaporation using a mixed solvent system, consisting of a 9:1 (v/v) ratio of acetone:methanol and light liquid paraffin as the dispersed and continuous phase. Span 80 was used as the surfactant to stabilize the emulsion. Scanning electron microscopy revealed that the microcapsules had a spherical shape. However, the particulate properties and in vitro release profile depended on the concentrations of the ethyl cellulose, Span 80 emulsifier, sucrose (pore inducer), and folic acid. The average diameter of the microcapsules increased from 300 to 448 microm, whilst the folic acid release rate decreased from 52% to 40%, as the ethyl cellulose concentration was increased from 2.5% to 7.5% (w/v). Increasing the Span 80 concentration from 1% to 4% (v/v) decreased the average diameter of microcapsules from 300 to 141 microm and increased the folic acid release rate from 52% to 79%. The addition of 2.5-7.5% (w/v) of sucrose improved the folic acid release from the microcapsules. The entrapment efficiency was improved from 64% to 88% when the initial folic acid concentration was increased from 1 to 3 mg/ml. PMID:19763838

  7. Evaluating the Potential Importance of Monoterpene Degradation for Global Acetone Production

    NASA Astrophysics Data System (ADS)

    Kelp, M. M.; Brewer, J.; Keller, C. A.; Fischer, E. V.

    2015-12-01

    Acetone is one of the most abundant volatile organic compounds (VOCs) in the atmosphere, but estimates of the global source of acetone vary widely. A better understanding of acetone sources is essential because acetone serves as a source of HOx in the upper troposphere and as a precursor to the NOx reservoir species peroxyacetyl nitrate (PAN). Although there are primary anthropogenic and pyrogenic sources of acetone, the dominant acetone sources are thought to be from direct biogenic emissions and photochemical production, particularly from the oxidation of iso-alkanes. Recent work suggests that the photochemical degradation of monoterpenes may also represent a significant contribution to global acetone production. We investigate that hypothesis using the GEOS-Chem chemical transport model. In this work, we calculate the emissions of eight terpene species (α-pinene, β-pinene, limonene, Δ3-carene, myrcene, sabinene, trans-β-ocimene, and an 'other monoterpenes' category which contains 34 other trace species) and couple these with upper and lower bound literature yields from species-specific chamber studies. We compare the simulated acetone distributions against in situ acetone measurements from a global suite of NASA aircraft campaigns. When simulating an upper bound on yields, the model-to-measurement comparison improves for North America at both the surface and in the upper troposphere. The inclusion of acetone production from monoterpene degradation also improves the ability of the model to reproduce observations of acetone in East Asian outflow. However, in general the addition of monoterpenes degrades the model comparison for the Southern Hemisphere.

  8. Expression of Clostridium acetobutylicum ATCC 824 Genes in Escherichia coli for Acetone Production and Acetate Detoxification

    PubMed Central

    Bermejo, Lourdes L.; Welker, Neil E.; Papoutsakis, Eleftherios T.

    1998-01-01

    A synthetic acetone operon (ace4) composed of four Clostridium acetobutylicum ATCC 824 genes (adc, ctfAB, and thl, coding for the acetoacetate decarboxylase, coenzyme A transferase, and thiolase, respectively) under the control of the thl promoter was constructed and was introduced into Escherichia coli on vector pACT. Acetone production demonstrated that ace4 is expressed in E. coli and resulted in the reduction of acetic acid levels in the fermentation broth. Since different E. coli strains vary significantly in their growth characteristics and acetate metabolism, ace4 was expressed in three E. coli strains: ER2275, ATCC 11303, and MC1060. Shake flask cultures of MC1060(pACT) produced ca. 2 mM acetone, while both strains ER2275(pACT) and ATCC 11303(pACT) produced ca. 40 mM acetone. Glucose-fed cultures of strain ATCC 11303(pACT) resulted in a 150% increase in acetone titers compared to those of batch shake flask cultures. External addition of sodium acetate to glucose-fed cultures of ATCC 11303(pACT) resulted in further increased acetone titers. In bioreactor studies, acidic conditions (pH 5.5 versus 6.5) improved acetone production. Despite the substantial acetone evaporation due to aeration and agitation in the bioreactor, 125 to 154 mM acetone accumulated in ATCC 11303(pACT) fermentations. These acetone titers are equal to or higher than those produced by wild-type C. acetobutylicum. This is the first study to demonstrate the ability to use clostridial genes in nonclostridial hosts for solvent production. In addition, acetone-producing E. coli strains may be useful hosts for recombinant protein production in that detrimental acetate accumulation can be avoided. PMID:9501448

  9. North American acetone sources determined from tall tower measurements and inverse modeling

    NASA Astrophysics Data System (ADS)

    Hu, L.; Millet, D. B.; Kim, S. Y.; Wells, K. C.; Griffis, T. J.; Fischer, E. V.; Helmig, D.; Hueber, J.; Curtis, A. J.

    2013-03-01

    We apply a full year of continuous atmospheric acetone measurements from the University of Minnesota tall tower Trace Gas Observatory (KCMP tall tower; 244 m a.g.l.), with a 0.5° × 0.667° GEOS-Chem nested grid simulation to develop quantitative new constraints on seasonal acetone sources over North America. Biogenic acetone emissions in the model are computed based on the MEGANv2.1 inventory. An inverse analysis of the tall tower observations implies a 37% underestimate of emissions from broadleaf trees, shrubs, and herbaceous plants, and an offsetting 40% overestimate of emissions from needleleaf trees plus secondary production from biogenic precursors. The overall result is a small (16%) model underestimate of the total primary + secondary biogenic acetone source in North America. Our analysis shows that North American primary + secondary anthropogenic acetone sources in the model (based on the EPA NEI 2005 inventory) are accurate to within approximately 20%. An optimized GEOS-Chem simulation incorporating the above findings captures 70% of the variance (R = 0.83) in the hourly measurements at the KCMP tall tower, with minimal bias. The resulting North American acetone source is 11 Tg a-1, including both primary emissions (5.5 Tg a-1) and secondary production (5.5 Tg a-1), and with roughly equal contributions from anthropogenic and biogenic sources. The North American acetone source alone is nearly as large as the total continental volatile organic compound (VOC) source from fossil fuel combustion. Using our optimized source estimates as a baseline, we evaluate the sensitivity of atmospheric acetone and peroxyacetyl nitrate (PAN) to shifts in natural and anthropogenic acetone sources over North America. Increased biogenic acetone emissions due to surface warming are likely to provide a significant offset to any future decrease in anthropogenic acetone emissions, particularly during summer.

  10. Process for the preparation of ethyl benzene

    DOEpatents

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

    1995-12-19

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

  11. Process for the preparation of ethyl benzene

    DOEpatents

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

    1995-01-01

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

  12. 21 CFR 184.1295 - Ethyl formate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... of concentrated sulfuric acid. Ethyl formate occurs naturally in some plant oils, fruits, and juices but does not occur naturally in the animal kingdom. (b) The ingredient meets the specifications of...

  13. 21 CFR 184.1295 - Ethyl formate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    .... Ethyl formate occurs naturally in some plant oils, fruits, and juices but does not occur naturally in the animal kingdom. (b) The ingredient meets the specifications of the “Food Chemicals Codex,” 3d...

  14. 21 CFR 184.1295 - Ethyl formate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... of concentrated sulfuric acid. Ethyl formate occurs naturally in some plant oils, fruits, and juices but does not occur naturally in the animal kingdom. (b) The ingredient meets the specifications of...

  15. Synthesis of New Functionalized Indoles Based on Ethyl Indol-2-carboxylate.

    PubMed

    Boraei, Ahmed T A; El Ashry, El Sayed H; Barakat, Assem; Ghabbour, Hazem A

    2016-01-01

    Successful alkylations of the nitrogen of ethyl indol-2-carboxylate were carried out using aq. KOH in acetone. The respective N-alkylated acids could be obtained without separating the N-alkylated esters by increasing the amount of KOH and water. The use of NaOMe in methanol led to transesterification instead of the alkylation, while the use of NaOEt led to low yields of the N-alkylated acids. Hydrazinolysis of the ester gave indol-2-carbohydrazide which then was allowed to react with different aromatic aldehydes and ketones in ethanol catalyzed by acetic acid. Indol-2-thiosemicarbazide was used in a heterocyclization reaction to form thiazoles. The new structures were confirmed using NMR, mass spectrometry and X-ray single crystal analysis. PMID:26978331

  16. Antitrypanosomal effects of petroleum ether, chloroform and methanol extracts of Artemisia maciverae Linn.

    PubMed

    Ene, A C; Atawodi, S E; Ameh, D A; Nnamani, C N; Apeh, Y E O

    2009-12-01

    Petroleum ether, chloroform and methanol extracts of A. maciverae were studied in vitro and in vivo for activity against Trypanosoma brucei brucei in Swiss albino mice. Thereafter, the chloroform extract which showed the highest activity in both in vitro and in vivo assessments was subjected to bioassay-guided fractionation. The crude extracts and the fractions of the chloroform extract of A. maciverae were screened for phytochemicals and secondary metabolites. Combined fractions 54-57 of this extract showed the highest in vitro antitrypanosomal activity, and at 10 mg/kg body weight, this fraction cleared the parasitemia completely from T. brucei brucei infected Swiss albino mice after 7 days of treatment. There was no statistically significant difference in the level of parasitemia when the infected mice treated with this fraction was compared with the standard trypanocidal drug, diminal. The results of the phytochemical analysis showed that the crude extracts contained secondary metabolites like flavonoids, triterpenes, terpenoids, tannins, phlobatannins and alkaloids, while the active fraction contains only triterpenes and alkaloids. It can be inferred that fraction 54-57 contains the active component responsible for the high antitrypanosomal activity of the chloroform extract of A. maciverae. PMID:20329702

  17. THE INFLUENCE OF ADVANCED AGE ON THE HEPATIC AND RENAL TOXICITY OF CHLOROFORM

    EPA Science Inventory

    THE INFLUENCE OF ADVANCED AGE ON THE HEPATIC AND RENAL TOXICITY OF CHLOROFORM (CHC13). A McDonald, Y M Sey and J E Simmons. NHEERL, ORD, U.S. EPA, RTP, NC.
    Disinfection, by chlorination or by ozonation followed by treatment with either chlorine or chloramine, of water containi...

  18. Evaluation of antiepileptic activity of chloroform extract of Acalypha fruticosa in mice

    PubMed Central

    Govindu, Sumalatha; Adikay, Sreedevi

    2014-01-01

    Aim: The aim of the present study is to evaluate the antiepileptic activity of chloroform extract of aerial parts of Acalypha fruticosa in mice. Materials and Methods: The antiepileptic activity of chloroform extract of A. fruticosa at the doses of 30, 100 and 300 mg/kg, p.o. was evaluated by maximum electroshock (MES), pentylenetetrazole (PTZ) and isoniazid (INH)-induced convulsions in mice. Statistical analysis was carried out by one-way analysis of variance followed by Dunnett's test. Results: In MES method, the chloroform extract significantly protected the mice from convulsions induced by electroshock method in a dose-dependent manner and exhibited more activity at the dose of 300 mg/kg when compared with diazepam treated animals. In PTZ method, the extract inhibited convulsions in mice potent than phenobarbitone sodium. In INH method, it delayed the latency of convulsions in mice in a dose-dependent manner but failed to protect the mice against mortality. Conclusion: The chloroform extract exhibited significant and dose-dependent antiepileptic activity, which may be due to the presence of antioxidant principles like flavanoids. PMID:24761113

  19. ESTIMATING CHLOROFORM BIOTRANSFORMATION IN F-344 RAT LIVER USING IN VITRO TECHNIQUES AND PHARMACOKINETIC MODELING

    EPA Science Inventory

    ESTIMATING CHLOROFORM BIOTRANSFORMATION IN F-344 RAT LIVER USING IN VITRO TECHNIQUES AND PHARMACOKINETIC MODELING

    Linskey, C.F.1, Harrison, R.A.2., Zhao, G.3., Barton, H.A., Lipscomb, J.C4., and Evans, M.V2., 1UNC, ESE, Chapel Hill, NC ; 2USEPA, ORD, NHEERL, RTP, NC; 3 UN...

  20. Three-dimensional simulations of atmospheric methyl chloroform - Effect of an ocean sink

    NASA Technical Reports Server (NTRS)

    Tie, X.; Kao, C.-Y.; Mroz, E. J.; Cicerone, R. J.; Alyea, F. N.; Cunnold, D. M.

    1992-01-01

    A global three-dimensional chemical tracer model of the distribution and seasonal cycles of the surface concentration of CH3CCl3 is compared with surface observations from the Atmospheric Lifetime Experiment (ALE) for the years 1980-1985. Two-dimensional OH distributions calculated by a photochemical model are empirically adjusted from observed trends in the global average and the interhemispheric ratio of methyl chloroform. The effects of the recently discovered ocean sink for methyl chloroform were investigated. The model simulates the 5-year record of observations made at the five ALE sampling sites to generally within +/- 5 percent of the observed mean. The calculated average global lifetime of methyl chloroform is 5.7 +/- 0.3 years. The estimated global mean OH concentration is 6.5 +/- 0.4 x 10 exp 5/cu cm. However, the inclusion of the ocean sink does not significantly improve the simulation of the observed interhemispheric gradient of methyl chloroform. Atmospheric transport dominates the simulated CH3CCl3 seasonal cycle throughout the Northern Hemisphere but is less important in the Southern Hemisphere.

  1. DOSE-RESPONSE STUDY OF CHLOROFORM CARCINOGENESIS IN THE MOUSE AND RAT: STATUS REPORT

    EPA Science Inventory

    Chloroform is being administered to male Osborne-Mendel rats and to female B6C3Fl mice at concentrations of 0 (negative control), 200, 400, 900 or 1800 ppm in the drinking water. Matched control groups of both species receive a volume of water identical to that consumed by the co...

  2. HEPATOTOXIC EVALUATION OF THE BINARY INTERACTIONS OF BROMODICHLOROMETHANE WITH CHLOROFORM, CHLORODIBROMOMETHANE AND BROMOFORM

    EPA Science Inventory

    HEPATOTOXIC EVALUATION OF THE BINARY INTERACTIONS OF BROMODICHLOROMETHANE (BDCM) WITH CHLOROFORM (CHC13), CHLORODIBROMOMETHANE (CDBM) AND BROMOFORM (CHBr3). Y M Se'', C Gennings2, A McDonald', L K Teuschler3, A Hamm2and J E Simmons .'NHEERL, ORD, U.S. EPA, RTP, NC; 2MCV, VCU, Ric...

  3. Compositional characteristics of a chloroform/methanol soluble protein fraction from spinach chloroplast membranes.

    PubMed

    Henriques, F; Park, R B

    1976-05-14

    Extraction of an aqueous suspension of spinach chloroplast lamellae with a chloroform/methanol mixture leads to solubilization of about 1/3 of the total membrane protein. Amino acid analysis of the chloroform/methanol-soluble protein shows that this fraction is largely enriched in the hydrophobic residues proline, leucine, alanine and phenylalanine and considerably depleted in polar amino acids, namely lysine and arginine. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the solubilized material reveals the presence of a variety of low molecular weight polypeptides (molecular weight less than or equal to 25 000), with more than 50% of the total fraction being contributed by a 25 000 dalton band. This band, which accounts for about 25% of the total chloroplast lamellar protein, has recently been identified as the main component of the light-harvesting chlorophyll-protein complex. The physiological role of most of the chloroform/methanol-soluble protein fraction is not known at present. From its chemical properties and apparent biological inertness, we propose that it plays mainly a structural role in situ, interacting with the lipid moiety of the chloroplast membrane. The material insoluble in the aqueous chloroform/methanol mixture is largely enriched in manganese, iron, cytochrome and water-soluble proteins, such as chloroplast coupling factor and ribulose diphosphate carboxylase. PMID:179588

  4. Predictive model for chloroform during disinfection of water for consumption, city of Montevideo.

    PubMed

    Gomez Camponovo, Mariana; Seoane Muniz, Gustavo; Rothenberg, Stephen J; Umpiérrez Vazquez, Eleuterio; Achkar Borras, Marcel

    2014-10-01

    The objective of this study was to predict chloroform formation resulting from the process of disinfecting water, particularly trihalomethane which is most frequently produced. A statistical model was used which included repeated measurements of water parameters used for monitoring water quality at 51 sites covering the municipal water system of Montevideo. Samples were taken considering different seasons from June 2009 to July 2011 in Montevideo. Total samples (n = 330) were analytically studied using the headspace-gas chromatography method coupled with mass spectrometry. Chloroform was the dependent variable and the covariables were pH, temperature, free chlorine, and total chlorine. A Tobit analysis with an unstructured correlation matrix was performed, and a significant interaction was found between pH and free chlorine for the prediction of chloroform formation. We concluded that parameters for the continuous control of water quality for consumption can be used to predict the levels of chloroform that may be present. Given the large measurement to variability found in the repeated measurements, the use of averages that include more than one season is not recommended to determine the degree of compliance with acceptable levels established by norms. PMID:24981876

  5. Persulfate Oxidation of MTBE- and Chloroform-Spent Granular Activated Carbon

    EPA Science Inventory

    Activated persulfate (Na2S2O8) regeneration of methyl tert-butyl ether (MTBE) and chloroform-spent GAC was evaluated in this study. Thermal-activation of persulfate was effective and resulted in greater MTBE removal than either alkaline-activation or H2O2–persulfate binary mixtur...

  6. IRIS TOXICOLOGICAL REVIEW AND SUMMARY DOCUMENTS FOR ACETONE (EXTERNAL REVIEW DRAFT)

    EPA Science Inventory

    Acetone is produced endogenously in the human body, although usually under conditions of stress such as starvation or high levels of exertion. Acetone is also produced synthetically for a range of commercial processes, mostly as a solvent and intermediate in the synthesis of high...

  7. Immunotoxicological Profile of Chloroform in Female B6c3f1 Mice When Administered In Drinking Water

    EPA Science Inventory

    Chloroform can be formed as a disinfection by-product during water chlorination, one of the primary modalities for purifying municipal water supplies for human consumption. The goal of this study was to characterize the immunotoxic effects of chloroform in female B6C3F1 mice when...

  8. Multiresidue pesticide analysis of ginseng powders using acetonitrile- or acetone-based extraction, solid-phase extraction cleanup, and gas chromatography-mass spectrometry/selective ion monitoring (GC-MS/SIM) or -tandem mass spectrometry (GC-MS/MS).

    PubMed

    Wong, Jon W; Zhang, Kai; Tech, Katherine; Hayward, Douglas G; Krynitsky, Alexander J; Cassias, Irene; Schenck, Frank J; Banerjee, Kaushik; Dasgupta, Soma; Brown, Don

    2010-05-26

    A multiresidue method for the analysis of 168 pesticides in dried powdered ginseng has been developed using acetonitrile or acetone mixture (acetone/cyclohexane/ethyl acetate, 2:1:1 v/v/v) extraction, solid-phase extraction (SPE) cleanup with octyl-bonded silica (C(8)), graphitized carbon black/primary-secondary amine (GCB/PSA) sorbents and toluene, and capillary gas chromatography-mass spectrometry/selective ion monitoring (GC-MS/SIM) or -tandem mass spectrometry (GC-MS/MS). The geometric mean limits of quantitation (LOQs) were 53 and 6 microg/kg for the acetonitrile extraction and 48 and 7 microg/kg for the acetone-based extraction for GC-MS/SIM and GC-MS/MS, respectively. Mean percent recoveries and standard deviations from the ginseng fortified at 25, 100, and 500 microg/kg using GC-MS/SIM were 87 +/- 10, 88 +/- 8, and 86 +/- 10% from acetonitrile extracts and 88 +/- 13, 88 +/- 12, and 88 +/- 14% from acetone mixture extracts, respectively. The mean percent recoveries from the ginseng at the 25, 100, and 500 microg/kg levels using GC-MS/MS were 83 +/- 19, 90 +/- 13, and 89 +/- 11% from acetonitrile extracts and 98 +/- 20, 91 +/- 13, and 88 +/- 14% from acetone extracts, respectively. Twelve dried ginseng products were found to contain one or more of the following pesticides and their metabolites: BHCs (benzene hexachlorides, alpha-, beta-, gamma-, and delta-), chlorothalonil, chlorpyrifos, DDT (dichlorodiphenyl trichloroethane), dacthal, diazinon, iprodione, quintozene, and procymidone ranging from <1 to >4000 microg/kg. No significant differences were found between the two extraction solvents, and GC-MS/MS was found to be more specific and sensitive than GC-MS/SIM. The procedures described were shown to be effective in screening, identifying, confirming, and quantitating pesticides in commercial ginseng products. PMID:20225896

  9. Photocatalytic oxidation of chloroform using immobilized-biogenic TiO2 nanoparticles

    NASA Astrophysics Data System (ADS)

    Kim, Y.; Cho, Y.; Yoo, H.

    2011-12-01

    Although commercial titanium dioxide (TiO2) nanoparticles as a suspension in water are one of the most popular photocatalysts for treatment of chlorinated organic compounds, the reuse and recovery of the nanoscale phtocatalyst is a practical challenge for application in water and groundwater treatment system. As part of efforts to overcome this practical limitation, development of immobilized TiO2 is needed. Diatom Pinnularia sp. were found to be capable of producing nanoscale TiO2 in their microscale silica shells. In order to obtain biogenic TiO2 nanoparticles from Pinnularia sp., soluble Ti was fed to the silicon-starved cells, resulting in deposition of titanium on the microscale features of the silica shells. After thermal treatment at 720 oC for 2 hr, the titanium was eventually converted to nanoscale TiO2. In order to determine the physical and chemical properties of the immobilized TiO2, material characterization such as TEM, STEM-EDS, BET and XRD analysis was carried out. In this study, a novel type of immobilized photocatalytic nanoparticles, biogenic TiO2 on silica shells was used for the mineralization of chloroform in water. Batch tests were conducted to evaluate the chloroform removal efficiency of biogenic and commercial TiO2 nanoparticles. Also, the amount of Cl- ions in water during the mineralization was measured to check mineralization of chloroform by biogenic TiO2 nanoparticles. Kinetic models were used to determine the rate of chloroform mineralization. In addition, the effect of UVA (ultraviolet-A) intensity on chloroform mineralization was investigated. The results obtained from this study could provide useful information for practical application of biogenic TiO2 in the groundwater treatment contaminated with some chlorinated organic compounds.

  10. Risk assessment of inhaled chloroform based on its mode of action.

    PubMed

    Wolf, D C; Butterworth, B E

    1997-01-01

    The development of scientifically sound risk assessments based on mechanistic data will enable society to better allocate scarce resources. Inadequate risk assessments may result in potentially dangerous levels of hazardous chemicals, whereas overly conservative estimates can result in unnecessary loss of products or industries and waste limited resources. Risk models are used to extrapolate from high-dose rodent studies to estimate potential effects in humans at low environmental exposures and determine a virtually safe dose (VSD). When information to the contrary is not available, the linearized multistage (LMS) model, a conservative model that assumes some risk of cancer at any dose, is traditionally employed. In the case of airborne chloroform, the dose at which an increased lifetime cancer risk of 10(-6) could be calculated was chosen as the target VSD. Applying the LMS model to the mouse liver tumor data from a corn-oil gavage bioassay yields a VSD of 0.000008 ppm chloroform in the air. The weight of evidence indicates that chloroform is not directly mutagenic but, rather, acts through a nongenotoxic-cytotoxic mode of action. In this case, tumor formation results from events secondary to induced cytolethality and regenerative cell proliferation. Toxicity is not observed in rodents when chloroform is not converted to toxic metabolites at a rate sufficient to kill cells. Thus, tumors would not be anticipated at doses that do not induce cytolethality, contrary to the predictions of the LMS model. Inhalation studies in rodents show no cytolethality or regenerative cell proliferation in mouse liver at a chloroform concentration of 10 ppm as the no observed effect level (NOEL) or below. Using that NOEL and a safety factor approach, one can develop a VSD of 0.01 ppm. Integrating these data into the risk assessment process will yield risk estimates that are appropriate to the route of administration and consistent with the mode of action. PMID:9061851

  11. Detection of acetone processing of castor bean mash for forensic investigation of ricin preparation methods.

    PubMed

    Kreuzer, Helen W; Wahl, Jon H; Metoyer, Candace N; Colburn, Heather A; Wahl, Karen L

    2010-07-01

    Samples containing the toxic castor bean protein ricin have been recently seized in connection with biocriminal activity. Analytical methods that enable investigators to determine how the samples were prepared and to match seized samples to potential source materials are needed. One commonly described crude ricin preparation method is acetone extraction of crushed castor beans. Here, we describe the use of solid-phase microextraction and headspace analysis to determine whether castor beans were processed by acetone extraction. We prepared acetone-extracted castor bean mash, along with controls of unextracted mash and mash extracted with nonacetone organic solvents. Samples of acetone-extracted mash and unextracted mash were stored in closed containers for up to 109 days at both room temperature and -20 degrees C, and in open containers at room temperature for up to 94 days. Acetone-extracted bean mash could consistently be statistically distinguished from controls, even after storage in open containers for 94 days. PMID:20345778

  12. Boron nitride nanotube based nanosensor for acetone adsorption: a DFT simulation.

    PubMed

    Ganji, Masoud Darvish; Rezvani, Mahyar

    2013-03-01

    We have investigated the adsorption properties of acetone on zigzag single-walled BNNTs using density functional theory (DFT) calculations. The results obtained show that acetone is strongly bound to the outer surface of a (5,0) BNNT on the top site directly above the boron atom, with a binding energy of -96.16 kJ mol(-1) and a B-O binding distance of 1.654 Å. Our first-principles calculations also predict that the ability of zigzag BNNTs to adsorb acetone is significantly stronger than the corresponding ability of zigzag CNTs. A comparative investigation of BNNTs with different diameters indicated that the ability of the side walls of the tubes to adsorb acetone decreases significantly for nanotubes with larger diameters. Furthermore, the stability of the most stable acetone/BNNT complex was tested using ab initio molecular dynamics simulation at room temperature. PMID:23179768

  13. Integration of stable isotope and trace contaminant concentration for enhanced forensic acetone discrimination

    SciTech Connect

    Moran, James J.; Ehrhardt, Christopher J.; Wahl, Jon H.; Kreuzer, Helen W.; Wahl, Karen L.

    2013-07-18

    We analyzed 21 neat acetone samples from 15 different suppliers to demonstrate the utility of a coupled stable isotope and trace contaminant strategy for distinguishing forensically-relevant samples. By combining these two pieces of orthogonal data we could discriminate all of the acetones that were produced by the 15 different suppliers. Using stable isotope ratios alone, we were able to distinguish 9 acetone samples, while the remaining 12 fell into four clusters with highly similar signatures. Adding trace chemical contaminant information enhanced discrimination to 13 individual acetones with three residual clusters. The acetones within each cluster shared a common manufacturer and might, therefore, not be expected to be resolved. The data presented here demonstrates the power of combining orthogonal data sets to enhance sample fingerprinting and highlights the role disparate data could play in future forensic investigations.

  14. 40 CFR 721.10595 - Octadecen-1-aminium, N-ethyl-N,N-dimethy-, ethyl sulfate (1:1).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Octadecen-1-aminium, N-ethyl-N,N... Significant New Uses for Specific Chemical Substances § 721.10595 Octadecen-1-aminium, N-ethyl-N,N-dimethy... chemical substance identified as octadecen-1-aminium, N-ethyl-N,N-dimethy-, ethyl sulfate (1:1) (PMN...

  15. An acetone bio-sniffer (gas phase biosensor) enabling assessment of lipid metabolism from exhaled breath.

    PubMed

    Ye, Ming; Chien, Po-Jen; Toma, Koji; Arakawa, Takahiro; Mitsubayashi, Kohji

    2015-11-15

    Several volatile organic compounds (VOCs) are released from human breath or skin. Like chemical substances in blood or urine, some of these vapors can provide valuable information regarding the state of the human body. A highly sensitive acetone biochemical gas sensor (bio-sniffer) was developed and used to measure exhaled breath acetone concentration, and assess lipid metabolism based on breath acetone analysis. A fiber-optic biochemical gas sensing system was constructed by attaching a flow-cell with nicotinamide adenine dinucleotide (NADH)-dependent secondary alcohol dehydrogenase (S-ADH) immobilized membrane onto a fiber-optic NADH measurement system. The NADH measurement system utilizes an ultraviolet-light emitting diode with peak emission of 335 nm as an excitation light source. NADH is consumed by the enzymatic reaction of S-ADH, and the consumption is proportional to the concentration of acetone vapor. Phosphate buffer which contained NADH was circulated into the flow-cell to rinse products and the excessive substrates from the optode. The change of fluorescent emitted from NADH is analyzed by the PMT. Hence, fluorescence intensity decreased as the acetone concentration increased. The relationship between fluorescence intensity and acetone concentration was identified from 20 ppb to 5300 ppb. This interval included the concentration of acetone vapor in the breath of healthy people and those suffering from disorders of carbohydrate metabolism. Finally, the acetone bio-sniffer was used to measure breath acetone during an exercise stress test on an ergometer after a period of fasting. The concentration of acetone in breath was shown to significantly increase after exercise. This biosensor allows rapid, highly sensitive and selective measurement of lipid metabolism. PMID:26079672

  16. North American acetone sources determined from tall tower measurements and inverse modelling

    NASA Astrophysics Data System (ADS)

    Hu, L.; Millet, D. B.; Kim, S. Y.; Wells, K. C.; Griffis, T. J.; Fischer, E. V.; Helmig, D.; Hueber, J.; Curtis, A. J.

    2012-11-01

    We apply a full year of continuous atmospheric acetone measurements from the University of Minnesota tall tower Trace Gas Observatory (KCMP tall tower; 244 m a.g.l.), with a 0.5° × 0.667° GEOS-Chem nested grid simulation to develop quantitative new constraints on seasonal acetone sources over North America, and assess the corresponding impacts on atmospheric chemistry. Biogenic acetone emissions in the model are computed based on the MEGANv2.1 inventory. An inverse analysis of the tall tower observations implies a 37% underestimate of emissions from broadleaf trees, shrubs, and herbaceous plants, and an offsetting 40% overestimate of emissions from needleleaf trees plus secondary production from biogenic precursors. The overall result is a small (16%) model underestimate of the total primary + secondary biogenic acetone source in North America. Our analysis shows that North American primary + secondary anthropogenic acetone sources in the model (based on the EPA NEI 2005 inventory) are accurate to within approximately 20%. An optimized GEOS-Chem simulation incorporating the above findings captures 70% of the variance (R=0.83) in the hourly measurements at the KCMP tall tower, with minimal bias. The resulting North American acetone source is 10.9 Tg a-1, including both primary emissions (5.5 Tg a-1) and secondary production (5.5 Tg a-1), and with roughly equal contributions from anthropogenic and biogenic sources. The North American acetone source alone is nearly as large as the total continental volatile organic compound (VOC) source from fossil fuel combustion. Using our optimized source estimates as a baseline, we evaluate the atmospheric impact of some potential future shifts in acetone sources over North America. Increased biogenic acetone emissions due to surface warming are likely to provide a significant offset to any future decrease in anthropogenic acetone emissions, particularly during summer.

  17. Formation of halogenated acetones in the lower troposphere

    NASA Astrophysics Data System (ADS)

    Sattler, Tobias; Wittmer, Julian; Krause, Torsten; Schöler, Heinz Friedrich; Kamilli, Katharina; Held, Andreas; Zetzsch, Cornelius; Ofner, Johannes; Atlas, Elliot

    2015-04-01

    Western Australia is a semi-/arid region that is heavily influenced by climate change and agricultural land use. The area is known for its saline lakes with a wide range of hydrogeochemical parameters and consists of ephemeral saline and saline groundwater fed lakes with a pH range from 2.5 to 7.1. In 2012 a novel PTFE-chamber was setup directly on the lakes. The 1.5 m³ cubic chamber was made of UV transparent PTFE foil to permit photochemistry while preventing dilution of the air due to lateral wind transport. This experimental setup allows linking measured data directly to the chemistry of and above the salt lakes. Air samples were taken using stainless steel canisters and measured by GC-MS/ECD. Sediment, crust and water samples were taken for investigation of potential VOC and VOX emissions in the laboratory using GC-MS. Several lakes were investigated and canister samples were taken over the day to see diurnal variations. The first samples were collected at 6 a.m. and from this time every 2 hours a canister was filled with chamber air. Concentrations of chloroacetone up to 15 ppb and of bromoacetone up to 40 ppb in the air samples were detected. The concentrations vary over the day and display their highest values around noon. Soil and water samples showed a variety of highly volatile and semi-volatile VOC/VOX but no halogenated acetones. An abiotic formation of these VOC/VOX seems conclusive due to iron-catalysed reactions below the salt crust [1]. The salt crust is the interface through which VOC/VOX pass from soil/groundwater to the atmosphere where they were photochemically altered. This explains the finding of halo acetones only in the air samples and not in water and soil samples measured in the laboratory. The main forming pathway for these haloacetones is the direct halogenation due to atomic chlorine and bromine above the salt lakes [2]. A minor pathway is the atmospheric degradation of chloropropane and bromopropane [3]. These halopropanes were found

  18. Conditioned Place Preference to Acetone Inhalation and the Effects on Locomotor Behavior and 18FDG Uptake

    SciTech Connect

    Pai, J.C.; Dewey, S.L.; Schiffer, W.; Lee, D.

    2006-01-01

    Acetone is a component in many inhalants that have been widely abused. While other solvents have addictive potential, such as toluene, it is unclear whether acetone alone contains addictive properties. The locomotor, relative glucose metabolism and abusive effects of acetone inhalation were studied in animals using the conditioned place preference (CPP) paradigm and [18F]2-fluorodeoxy-D-glucose (18FDG) imaging. The CPP apparatus contains two distinct conditioning chambers and a middle adaptation chamber, each lined with photocells to monitor locomotor activity. Adolescent Sprague-Dawley rats (n=16; 90-110 g) were paired with acetone in least preferred conditioning chamber, determined on the pretest day. The animals were exposed to a 10,000 ppm dose for an hour, alternating days with air. A CPP test was conducted after the 3rd, 6th and 12th pairing. In these same animals, the relative glucose metabolism effects were determined using positron emission tomography (PET) imaging with 18FDG. Following the 3rd pairing, there was a significant aversion to the acetone paired chamber (190.9 ± 13.7 sec and 241.7 ± 16.9 sec, acetone and air, respectively). After the 6th pairing, there was no significant preference observed with equal time spent in each chamber (222 ± 21 sec and 207 ± 20 sec, acetone and air-paired, respectively). A similar trend was observed after the 12th pairing (213 ± 21 sec and 221 ± 22 sec, acetone and air-paired, respectively). Locomotor analysis indicated a significant decrease (p<0.05) from air pairings to acetone pairings on the first and sixth pairings. The observed locomotor activity was characteristic of central nervous system (CNS) depressants, without showing clear abusive effects in this CPP model. In these studies, acetone vapors were not as reinforcing as other solvents, shown by overall lack of preference for the acetone paired side of the chamber. PET imaging indicated a regionally specific distribution of 18FDG uptake following

  19. A Portable Real-Time Ringdown Breath Acetone Analyzer: Toward Potential Diabetic Screening and Management.

    PubMed

    Jiang, Chenyu; Sun, Meixiu; Wang, Zhennan; Chen, Zhuying; Zhao, Xiaomeng; Yuan, Yuan; Li, Yingxin; Wang, Chuji

    2016-01-01

    Breath analysis has been considered a suitable tool to evaluate diseases of the respiratory system and those that involve metabolic changes, such as diabetes. Breath acetone has long been known as a biomarker for diabetes. However, the results from published data by far have been inconclusive regarding whether breath acetone is a reliable index of diabetic screening. Large variations exist among the results of different studies because there has been no "best-practice method" for breath-acetone measurements as a result of technical problems of sampling and analysis. In this mini-review, we update the current status of our development of a laser-based breath acetone analyzer toward real-time, one-line diabetic screening and a point-of-care instrument for diabetic management. An integrated standalone breath acetone analyzer based on the cavity ringdown spectroscopy technique has been developed. The instrument was validated by using the certificated gas chromatography-mass spectrometry. The linear fittings suggest that the obtained acetone concentrations via both methods are consistent. Breath samples from each individual subject under various conditions in total, 1257 breath samples were taken from 22 Type 1 diabetic (T1D) patients, 312 Type 2 diabetic (T2D) patients, which is one of the largest numbers of T2D subjects ever used in a single study, and 52 non-diabetic healthy subjects. Simultaneous blood glucose (BG) levels were also tested using a standard diabetic management BG meter. The mean breath acetone concentrations were determined to be 4.9 ± 16 ppm (22 T1D), and 1.5 ± 1.3 ppm (312 T2D), which are about 4.5 and 1.4 times of the one in the 42 non-diabetic healthy subjects, 1.1 ± 0.5 ppm, respectively. A preliminary quantitative correlation (R = 0.56, p < 0.05) between the mean individual breath acetone concentration and the mean individual BG levels does exist in 20 T1D subjects with no ketoacidosis. No direct correlation is observed in T1D subjects, T2D

  20. Catalytic purification of wastewaters containing formaldehyde, methyl alcohol, and acetone

    SciTech Connect

    Rachkovskaya, L.N.; Anisiforov, G.I.; Levitskii, E.A.; Kundo, N.N.

    1982-01-10

    A catalytic method for purification of wastewaters containing alcohols, aldehydes, and ketones is described in the literature. A current of steam containing gaseous organic compounds is passed over a complete-oxidation catalyst at temperatures of 250-700/sup 0/C. The organic compounds are oxidized to carbon dioxide. The main drawback of this method is that the wastewater must be evaporated and the vapor heated to high temperatures, involving a high consumption of fuel. Methods of liquid-phase catalytic oxidation under pressure are free from this drawback. A patent describes liquid-phase oxidation of phenol, analine, nitrobenzene, glycol, and dimethylformamide at temperatures of 275-300/sup 0/C under air pressures up to 100 atm in presence of oxides of copper, chromium, and zinc; a metallic catalyst consisting of copper, chromium, and manganese; copper oxide deposited on magnesium silicate. In a contact time of 8-10 min the degree of oxidation is 90-99%. It is known that liquid-phase oxidation of formaldehyde without a catalyst at 200/sup 0/C and 120 atm with a contact time of 4 h results in 80% oxidation of formaldehyde to methyl formate undergoes 10% conversion into acetic acid, while methyl alcohol is not oxidized at all. In this communication we describe liquid-phase catalytic oxidation of model wastewater containing formaldehyde, methyl alcohol, and acetone at temperatures up to 250/sup 0/C and oxygen pressures up to 20 atm.

  1. Theoretical and experimental investigation of electron collisions with acetone

    NASA Astrophysics Data System (ADS)

    Homem, M. G. P.; Iga, I.; da Silva, L. A.; Ferraz, J. R.; Machado, L. E.; de Souza, G. L. C.; da Mata, V. A. S.; Brescansin, L. M.; Lucchese, R. R.; Lee, M.-T.

    2015-09-01

    We report a joint theoretical-experimental investigation on elastic electron scattering by acetone in the low- and intermediate-energy regions. More specifically, experimental differential, integral, and momentum-transfer cross sections are given in the 30-800 eV and 10∘-120∘ ranges. Theoretical cross sections are reported in the 1-500 eV interval. The experimental differential cross sections were determined using a crossed electron-beam-molecular-beam geometry, whereas the absolute values of the cross sections were obtained using the relative-flow technique. Theoretically, a complex optical potential derived from a Hartree-Fock molecular wave function was used to represent the collision dynamics, and a single-center expansion method combined with the Padé approximant technique was used to solve the scattering equations. Our experimental cross-section data are in generally good agreement with the present calculated data. Also, our calculated grand-total and total absorption cross sections are in good agreement with the experimental results reported in the literature. Nevertheless, our calculations have revealed a strong shape resonance in the 2B2 scattering channel not clearly seen in the experimental results. Possible reasons for this fact are also discussed.

  2. Derivatization reaction-based surface-enhanced Raman scattering (SERS) for detection of trace acetone.

    PubMed

    Zheng, Ying; Chen, Zhuo; Zheng, Chengbin; Lee, Yong-Ill; Hou, Xiandeng; Wu, Li; Tian, Yunfei

    2016-08-01

    A facile method was developed for determination of trace volatile acetone by coupling a derivatization reaction to surface-enhanced Raman scattering (SERS). With iodide modified Ag nanoparticles (Ag IMNPs) as the SERS substrate, acetone without obvious Raman signal could be converted to SERS-sensitive species via a chemical derivatization reaction with 2,4-dinitrophenylhydrazine (2,4-DNPH). In addition, acetone can be effectively separated from liquid phase with a purge-sampling device and then any serious interference from sample matrices can be significantly reduced. The optimal conditions for the derivatization reaction and the SERS analysis were investigated in detail, and the selectivity and reproducibility of this method were also evaluated. Under the optimal conditions, the limit of detection (LOD) for acetone was 5mgL(-1) or 0.09mM (3σ). The relative standard deviation (RSD) for 80mgL(-1) acetone (n=9) was 1.7%. This method was successfully used for the determination of acetone in artificial urine and human urine samples with spiked recoveries ranging from 92% to 110%. The present method is convenient, sensitive, selective, reliable and suitable for analysis of trace acetone, and it could have a promising clinical application in early diabetes diagnosis. PMID:27216660

  3. PPy/PMMA/PEG-based sensor for low-concentration acetone detection

    NASA Astrophysics Data System (ADS)

    Daneshkhah, A.; Shrestha, S.; Agarwal, M.; Varahramyan, K.

    2014-05-01

    A polymer pellet-based sensor device comprised of polypyrrole (PPy), polymethyl methacrylate (PMMA) and polyethylene glycol (PEG), its fabrication methods, and the experimental results for low-concentration acetone detection are presented. The design consists of a double layer pellet, where the top layer consists of PPy/PMMA and the bottom layer is composed of PPy/PMMA/PEG. Both sets of material compositions are synthesized by readily realizable chemical polymerization techniques. The mechanism of the sensor operation is based on the change in resistance of PPy and the swelling of PMMA when exposed to acetone, thereby changing the resistance of the layers. The resistances measured on the two layers, and across the pellet, are taken as the three output signals of the sensor. Because the PPy/PMMA and PPy/PMMA/PEG layers respond differently to acetone, as well as to other volatile organic compounds, it is demonstrated that the three output signals can allow the presented sensor to have a better sensitivity and selectivity than previously reported devices. Materials characterizations show formation of new composite with PPy/PMMA/PEG. Material response at various concentrations of acetone was conducted using quartz crystal microbalance (QCM). It was observed that the frequency decreased by 98 Hz for 290 ppm of acetone and by 411 Hz for 1160 ppm. Experimental results with a double layer pellet of PPy/PMMA and PPy/PMMA/PEG show an improved selectivity of acetone over ethanol. The reported acetone sensor is applicable for biomedical and other applications.

  4. Protein precipitation of diluted samples in SDS-containing buffer with acetone leads to higher protein recovery and reproducibility in comparison with TCA/acetone approach.

    PubMed

    Santa, Cátia; Anjo, Sandra I; Manadas, Bruno

    2016-07-01

    Proteomic approaches are extremely valuable in many fields of research, where mass spectrometry methods have gained an increasing interest, especially because of the ability to perform quantitative analysis. Nonetheless, sample preparation prior to mass spectrometry analysis is of the utmost importance. In this work, two protein precipitation approaches, widely used for cleaning and concentrating protein samples, were tested and compared in very diluted samples solubilized in a strong buffer (containing SDS). The amount of protein recovered after acetone and TCA/acetone precipitation was assessed, as well as the protein identification and relative quantification by SWATH-MS yields were compared with the results from the same sample without precipitation. From this study, it was possible to conclude that in the case of diluted samples in denaturing buffers, the use of cold acetone as precipitation protocol is more favourable than the use of TCA/acetone in terms of reproducibility in protein recovery and number of identified and quantified proteins. Furthermore, the reproducibility in relative quantification of the proteins is even higher in samples precipitated with acetone compared with the original sample. PMID:27094026

  5. Comment on "Can existing models quantitatively describe the mixing behavior of acetone with water" [J. Chem. Phys. 130, 124516 (2009)].

    PubMed

    Kang, Myungshim; Perera, Aurelien; Smith, Paul E

    2009-10-21

    A recent publication indicated that simulations of acetone-water mixtures using the KBFF model for acetone indicate demixing at mole fractions less than 0.28 of acetone, in disagreement with experiment and two previously published studies. Here, we indicate some inconsistancies in the current study which could help to explain these differences. PMID:20568888

  6. Evaluation of Tribulus terrestris Linn (Zygophyllaceae) acetone extract for larvicidal and repellence activity against mosquito vectors.

    PubMed

    Singh, S P; Raghavendra, K; Singh, R K; Mohanty, S S; Dash, A P

    2008-12-01

    Acetone extracts of leaves and seeds from the Tribulus terrestris (Zygophyllaceae) were tested against mature and immature different mosquito vectors under laboratory condition. The extract showed strong larvicidal, properties 100 per cent mortality in the 3rd-instar larvae was observed in the bioassays with An. culicifacies Giles species A, An. stephensi Liston, Culex quinquefasciatus Say and Aedes aegypti Linn, against 200 ppm of the leaf acetone extract and 100 ppm seed acetone extract. The LC50 values of leaf acetone extract estimated for 3rd-instars An. culicifacies species A, An. stephensi, Cx. quinquefasciatus and Ae. aegypti after 24 hour of exposure were 117, 124, 168 and 185 ppm respectively. The LC50 values of seed acetone extract estimated for 3rd-instars An. culicifacies species A, An. stephensi, Cx. quinquefasciatus and Ae. aegypti after 24 hour of exposure were 100, 72, 91 and 91 ppm respectively. It is confirmed from the LC50 values that the seed acetone extract of T. terrestris is more effective compared to leaf extracts. A significant (P<0.004) higher concentration of acetone extract leaf was required to kill equal number of larvae i.e. against acetone extract of seed. The seed acetone extract showed strong repellent activity against adults mosquitoes. Per cent protection obtained against Anopheles culicifacies species A 100% repellency in 1 h, 6 h; Anopheles stephensi 100% repellency in 0 h, 4 h, 6 h; and Culex quinquefasciatus 100% repellency in 0 h, 2 h, 4 h, at 10% concentration respectively. Against Deet- 2.5% An. culicifacies Giles species A has shown 100% repellency in 1 h, 2 h, 6 h, An. stephensi Liston 99% repellency in 4 h, and Culex quinquefasciatus Say has shown 100% repellency in 1 h, 2 h. PMID:19579717

  7. North American acetone sources determined from tall tower measurements and inverse modelling

    NASA Astrophysics Data System (ADS)

    Hu, L.; Millet, D. B.; Kim, S.; Wells, K. C.; Griffis, T. J.; Helmig, D.; Fischer, E. V.

    2012-12-01

    Acetone ((CH3)2CO) plays an important role in the atmosphere as a source of peroxyacetylnitrate (PAN) and hydrogen oxide radicals (HOx). We apply a full year of continuous atmospheric acetone measurements from the University of Minnesota tall tower Trace Gas Observatory (KCMP tall tower; 244m a.g.l.), with a 0.5° × 0.667° GEOS-Chem nested grid simulation to develop quantitative new constraints on seasonal acetone sources over North America, and assess the corresponding impacts on atmospheric chemistry. Biogenic acetone emissions in the model are computed based on the MEGANv2.1 inventory, and an inverse analysis of the tall tower observations implies a 37% underestimate of emissions from broadleaf trees, shrubs, and herbaceous plants, and an offsetting 40% overestimate of emissions from needleleaf trees plus secondary production from biogenic precursors. The overall result is a small (15%) model underestimate of the total primary + secondary biogenic acetone source in North America. Our analysis shows that North American primary + secondary anthropogenic acetone sources in the model (based on EPA's NEI 2005 inventory) are accurate to within approximately 20%. An optimized GEOS-Chem simulation incorporating the above findings captures 70% of the variance (R = 0.83) in the hourly measurements at KCMP tall tower, with minimal bias. The resulting North American acetone source is 10.9 Tg/y, including both primary emissions and secondary production, with roughly equal contributions from anthropogenic and biogenic sources. The North American acetone source is nearly as large (75%) as the total continental VOC source from fossil fuel combustion. We find during winter that acetone in the US Upper Midwest arises mainly from sources outside North America (50%), with primary (15%) and secondary (29%) anthropogenic sources within North America also important. During summer, North American biogenic sources predominate (47% primary; 14% secondary), with anthropogenic sources

  8. 40 CFR 721.10244 - Phosphonic acid, P-[2-[bis(2-hydroxyethyl)amino]ethyl]-, 2-[bis(2- chloroethoxy)phosphinyl]ethyl...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Phosphonic acid, P- ethyl]-, 2- ethyl... New Uses for Specific Chemical Substances § 721.10244 Phosphonic acid, P- ethyl]-, 2- ethyl 2... substance identified as phosphonic acid, P- ethyl]-, 2- ethyl 2-chloroethyl ester (PMN P-09-195; CAS...

  9. 40 CFR 721.10244 - Phosphonic acid, P-[2-[bis(2-hydroxyethyl)amino]ethyl]-, 2-[bis(2- chloroethoxy)phosphinyl]ethyl...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Phosphonic acid, P- ethyl]-, 2- ethyl... New Uses for Specific Chemical Substances § 721.10244 Phosphonic acid, P- ethyl]-, 2- ethyl 2... substance identified as phosphonic acid, P- ethyl]-, 2- ethyl 2-chloroethyl ester (PMN P-09-195; CAS...

  10. 40 CFR 721.10244 - Phosphonic acid, P-[2-[bis(2-hydroxyethyl)amino]ethyl]-, 2-[bis(2- chloroethoxy)phosphinyl]ethyl...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Phosphonic acid, P- ethyl]-, 2- ethyl... New Uses for Specific Chemical Substances § 721.10244 Phosphonic acid, P- ethyl]-, 2- ethyl 2... substance identified as phosphonic acid, P- ethyl]-, 2- ethyl 2-chloroethyl ester (PMN P-09-195; CAS...

  11. Characteristics of acetone cluster ion beam for surface processing and modification

    NASA Astrophysics Data System (ADS)

    Ryuto, H.; Kakumoto, Y.; Takeuchi, M.; Takaoka, G. H.

    2014-02-01

    An acetone cluster ion beam was produced by the adiabatic expansion method without using helium as a support gas. The cluster source for the production of ethanol clusters was replaced with that sealed with metal gaskets. The Laval nozzle for the production of ethanol clusters was also replaced with a stainless steel conical nozzle. The cluster size distributions of the acetone cluster ion beams had mean values approximately at 2 × 103 molecules and increased with source pressure. The typical beam current density of the acetone cluster ion beam was approximately 0.5 μA/cm2.

  12. Extraction of selected organic bases by bis 1,2-dicarbollylcobaltate anion from water into chloroform

    NASA Astrophysics Data System (ADS)

    Navrátil, O.; Skaličan, Z.; Kobliha, Z.; Halámek, E.

    1999-01-01

    Bis-1,2-dicarbollylcobaltate anion, labelled by 60Co, forms ionic associates with cations of some organic bases and quaternary salts, especially those causing psychic effect on human organism. Their stability and partition between aqueous 0,1 mol. L-1 HCl and chloroform were investigated radiometrically. A method of competitive extraction was proposed for some anions of dyes which were so far used for extraction-spectrophotometric determination of some bases.

  13. The effect of chloroform, orange oil and eucalyptol on root canal transportation in endodontic retreatment.

    PubMed

    Karataş, Ertuğrul; Kol, Elif; Bayrakdar, İbrahim Şevki; Arslan, Hakan

    2016-04-01

    The purpose of the present study was to assess the effect of solvents on root canal transportation in endodontic retreatment. Sixty extracted human permanent mandibular first molars with curved root canals were selected. All of the root canals were prepared using Twisted File Adaptive instruments (SybronEndo, Orange, CA, USA) and filled with gutta-percha and AH Plus sealer (Dentsply DeTrey, Konstanz, Germany) using the cold lateral compaction technique. The teeth were assigned to four retreatment groups as follows (n = 15): eucalyptol, chloroform, orange oil and control. The canals were scanned using cone-beam computed tomography scanning before and after instrumentation. The chloroform group showed a significantly higher mean transportation value than the orange oil and control groups at the 3 and 5 mm levels (P = 0.011 and P = 0.003, respectively). There was no significant difference among the orange oil, eucalyptol and control groups in terms of canal transportation (P > 0.61). The chloroform led to more canal transportation than the eucalyptol and orange oil during endodontic retreatment. PMID:26420757

  14. Effect of Chloroform, Eucalyptol and Orange Oil Solvents on the Microhardness of Human Root Dentin

    PubMed Central

    Khedmat, Sedigheh; Hashemi, Alaleh; Dibaji, Fatemeh; Kharrazifard, Mohammad Javad

    2015-01-01

    Objectives: This study aimed to assess the effect of chloroform, eucalyptol and orange oil solvents on the microhardness of human root dentin. Materials and Methods: Sixty-eight single-rooted single-canal extracted human premolar teeth were used. Tooth crowns were separated from the roots at the cementoenamel junction (CEJ). Roots were buccolingually sectioned into mesial and distal halves. Specimens were randomly divided into 5 groups, with 20 teeth in each solvent group and 4 teeth in each control group. Primary microhardness of specimens was measured using Vickers microhardness tester. Specimens were exposed to solvents for 15 minutes and were subjected to microhardness testing again. Data were recorded and analyzed using repeated measure ANOVA. Results: No significant difference was found in dentin microhardness before and after exposure to solvents in any of the orange oil, eucalyptol, chloroform or saline groups (P=0.727). None of the experimental groups showed any significant difference in terms of dentin microhardness reduction (P=0.99) and had no significant difference with the negative control group. Conclusion: This study showed that chloroform, eucalyptol and orange oil as gutta percha solvents did not decrease the microhardness of root dentin. Thus, none of the mentioned solvents has any superiority over the others in terms of affecting dentin properties. PMID:26005451

  15. The interaction of fluorescent Pyronin Y molecules with monodisperse silver nanoparticles in chloroform

    NASA Astrophysics Data System (ADS)

    Şenol, Ayşe Merve; Metin, Önder; Acar, Murat; Onganer, Yavuz; Meral, Kadem

    2016-01-01

    The interaction of fluorescent Pyronin Y (PyY) molecules with monodisperse silver nanoparticles (Ag NPs) in chloroform was studied by using UV-Vis, steady-state and time-resolved fluorescence spectroscopies. Monodisperse Ag NPs were synthesized by using a surfactant assisted organic solution phase protocol comprising the tandem thermal decomposition and reduction of silver (I) acetate in oleic acid and oleylamine at 180 °C. The average particle size of Ag NPs was determined to be ˜3 nm by transmission electron microcopy (TEM) and their X-ray diffraction (XRD) pattern revealed the face centered cubic crystal phase. Afterward, PyY and monodisperse Ag NPs were interacted in chloroform via sonication at various time periods. The obtained spectroscopic results revealed that the photophysical properties of PyY molecules were dramatically changed after their interaction with Ag NPs in chloroform. It was determined that the amount of Ag NPs and PyY has the major effects on the photophysical properties of the dye.

  16. Ozonolysis at vegetation surfaces. a source of acetone, 4-oxopentanal, 6-methyl-5-hepten-2-one, and geranyl acetone in the troposphere

    NASA Astrophysics Data System (ADS)

    Fruekilde, P.; Hjorth, J.; Jensen, N. R.; Kotzias, D.; Larsen, B.

    The present study gives a possible explanation for the ubiquitous occurrence of 6-methyl-5-hepten-2-one and acetone in ambient air and reports for the first time on a widespread occurrence of geranyl acetone and 4-oxopentanal. We have conducted a series of laboratory experiments in which it is demonstrated that significant amounts of geranyl acetone, 6-methyl-5-hepten-2-one (6-MHO), 4-oxopentanal (4-OPA), and acetone are formed by the reaction of ozone with foliage of common vegetation in the Mediterranean area ( Quercus ilex>Citrus sinensis>Quercus suber>Quercus freinetto>Pinus pinea). In order to rule out biological formation, epicuticular waxes were extracted from the leaves, dispersed on glass wool and allowed to react with a flow of artificial air. Significant amounts of 6-MHO and 4-OPA were formed at ozone concentrations of 50-100 ppbv, but not at zero ozone. A number of terpenoids common in vegetation contain the structural element necessary for ozonolytic formation of 6-MHO. Two sesquiterpenes (nerolidol; farnesol), and a triterpene (squalene) selected as representative test compounds were demonstrated to be strong precursors for acetone, 4-OPA, and 6-MHO. Squalene was also a strong precursor for geranyl acetone. The atmospheric lifetime of geranyl acetone and 6-MHO is less than 1 h under typical conditions. For the present study, we have synthesized 4-OPA and investigated the kinetics of its gas-phase reaction with OH, NO 3, and O 3. A tropospheric lifetime longer than 17 h under typical conditions was calculated from the measured reaction rate constants, which explains the tropospheric occurrence of 4-OPA. It is concluded that future atmospheric chemistry investigations should included geranyl acetone, 6-MHO, and 4-OPA. In a separate experiment it was demonstrated that human skin lipid which contains squalene as a major component is a strong precursor for the four above-mentioned compounds plus nonanal and decanal. The accidental touching of material

  17. Effect of some parameters on the formation of chloroform during chloramination of aqueous solutions of resorcinol.

    PubMed

    Cimetiere, Nicolas; Dossier-Berne, Florence; De Laat, Joseph

    2010-08-01

    The effects of various factors (N/Cl ratio used to prepare monochloramine, monochloramine doses, pH and contact time) on the monochloramine demand and on the chloroform yield during chloramination of resorcinol have been investigated. Chloramination experiments were carried out at 24+/-1 degrees C, at pH values ranging from 6.5 to 12 using a bicarbonate/carbonate buffer and preformed monochloramine solutions prepared at pH 8.5 with N/Cl ratios ([NH(4)Cl](0)/[Total free Cl(2)](0) ranging from 1.0 to 150 mol/mol). Kinetic experiments ([Resorcinol](0)=5 or 100 microM, [NH(2)Cl](0)/[Resorcinol](0)=20 mol/mol, pH=8.5+/-0.1) showed a slow increase of the monochloramine consumption with reaction time. The monochloramine demands after reaction times of 7 days ([Resorcinol](0)=100 microM) and 14 days ([Resorcinol](0)=5 microM) were equal to 8.5 mol of NH(2)Cl/mole of resorcinol and were higher than the chlorine demands (approximately 7.3 mol/mol). Chloroform yields from monochloramination of resorcinol were lower than 8% (<80 mmol of CHCl(3)/mole of resorcinol) and were less than the yields obtained by chlorination (0.9-0.95 mol/mol). Chloroform productions increased with increasing monochloramine dose and reaction time and decreased with increasing pH values within the pH range 6.5-10. Chloroform formation markedly decreased when the N/Cl ratio increased from 1 to 1.5 mol/mol and was suppressed at N/Cl>100 mol/mol. The data obtained in the present work suggest that free chlorine released from monochloramine hydrolysis plays a significant role on the formation of chloroform during chloramination of resorcinol at N/Cl ratios close to unity (1.0

  18. Reaction of benzophenone UV filters in the presence of aqueous chlorine: kinetics and chloroform formation.

    PubMed

    Duirk, Stephen E; Bridenstine, David R; Leslie, Daniel C

    2013-02-01

    The transformation of two benzophenone UV filters (Oxybenzone and Dioxybenzone) was examined over the pH range 6-11 in the presence of excess aqueous chlorine. Under these conditions, both UV filters were rapidly transformed by aqueous chlorine just above circumneutral pH while transformation rates were significantly lower near the extremes of the pH range investigated. Observed first-order rate coefficients (k(obs)) were obtained at each pH for aqueous chlorine concentrations ranging from 10 to 75 μM. The k(obs) were used to determine the apparent second-order rate coefficient (k(app)) at each pH investigated as well as determine the reaction order of aqueous chlorine with each UV filter. The reaction of aqueous chlorine with either UV filter was found to be an overall second-order reaction, first-order with respect to each reactant. Assuming elemental stoichiometry described the reaction between aqueous chlorine and each UV filter, models were developed to determine intrinsic rate coefficients (k(int)) from the k(app) as a function of pH for both UV filters. The rate coefficients for the reaction of HOCl with 3-methoxyphenol moieties of oxybenzone (OXY) and dioxybenzone (DiOXY) were k(1,OxY) = 306 ± 81 M⁻¹s⁻¹ and k(1,DiOxY) = 154 ± 76 M⁻¹s⁻¹, respectively. The k(int) for the reaction of aqueous chlorine with the 3-methoxyphenolate forms were orders of magnitude greater than the un-ionized species, k(2,OxY) = 1.03(±0.52) × 10⁶ M⁻¹s⁻¹ and k(2_1,DiOxY) = 4.14(±0.68) × 10⁵ M⁻¹s⁻¹. Also, k(int) for the reaction of aqueous chlorine with the DiOXY ortho-substituted phenolate moiety was k(2_2,DiOxY) = 2.17(±0.30) × 10³ M⁻¹s⁻¹. Finally, chloroform formation potential for OXY and DiOXY was assessed over the pH range 6-10. While chloroform formation decreased as pH increased for OXY, chloroform formation increased as pH increased from 6 to 10 for DiOXY. Ultimate molar yields of chloroform per mole of UV filter were pH dependent

  19. Polypyrrole nanoparticles fabricated via Triton X-100 micelles template approach and their acetone gas sensing property

    NASA Astrophysics Data System (ADS)

    Li, Fake; Li, Hang; Jiang, Hongmin; Zhang, Kejun; Chang, Kai; Jia, Shuangrong; Jiang, Wenbin; Shang, Ya; Lu, Weiping; Deng, Shaoli; Chen, Ming

    2013-09-01

    Nano-scaled polypyrrole (PPy) particles have been successfully synthesized with the help of Triton X-100 micelles via soft template approach. The polypyrrole nanoparticles have been spin-coated on surface acoustic wave (SAW) transducers to demonstrate their sensing capability toward acetone gas exposure. Field Emission Scanning Electron Microscopes (FE-SEM) and Fourier transform infrared (FT-IR) spectroscopy have been utilized to characterize these PPy nanoparticles. The PPy nanoparticles have an average diameter of 95 nm. The responses of the sensors are linearly associated with the acetone concentrations in the range from 5.5 ppm to 80 ppm. In response to 5.5 ppm acetone exposure, the response and recovery time are 9 s and 8.3 s, respectively. SAW sensors coated with PPy nanoparticles were potentially useful to detect acetone.

  20. Elastic electron scattering by ethyl vinyl ether

    SciTech Connect

    Khakoo, M. A.; Hong, L.; Kim, B.; Winstead, C.; McKoy, V.

    2010-02-15

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

  1. Ethyl p-nitrophenyl phenylphosphorothioate (EPN)

    Integrated Risk Information System (IRIS)

    Ethyl p - nitrophenyl phenylphosphorothioate ( EPN ) ; CASRN 2104 - 64 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Ha

  2. 21 CFR 184.1295 - Ethyl formate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethyl formate. 184.1295 Section 184.1295 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) DIRECT FOOD SUBSTANCES AFFIRMED AS GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS §...

  3. 21 CFR 184.1295 - Ethyl formate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ethyl formate. 184.1295 Section 184.1295 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) DIRECT FOOD SUBSTANCES AFFIRMED AS GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS §...

  4. 49 CFR 173.322 - Ethyl chloride.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Ethyl chloride. 173.322 Section 173.322 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SHIPPERS-GENERAL REQUIREMENTS FOR SHIPMENTS AND PACKAGINGS Gases; Preparation...

  5. Manufacturing Ethyl Acetate From Fermentation Ethanol

    NASA Technical Reports Server (NTRS)

    Rohatgi, Naresh K.; Ingham, John D.

    1991-01-01

    Conceptual process uses dilute product of fermentation instead of concentrated ethanol. Low-concentration ethanol, extracted by vacuum from fermentation tank, and acetic acid constitutes feedstock for catalytic reaction. Product of reaction goes through steps that increases ethyl acetate content to 93 percent by weight. To conserve energy, heat exchangers recycle waste heat to preheat process streams at various points.

  6. Striations in an ethyl alcohol glow discharge

    NASA Astrophysics Data System (ADS)

    Reyes, P. G.; Gómez, A.; Torres, C.; Martínez, H.; Castillo, F.; Vergara, J.

    2015-03-01

    This research shows the behavior of striations in glow discharge generated with high purity ethyl alcohol at a pressure of 0.6 Torr. This paper present the number of striations as a function of the of current and voltage discharge.

  7. Preparation and properties of low boiling point of alcohol and acetone-based magnetic fluid

    NASA Astrophysics Data System (ADS)

    Fujita, T.; Miyazaki, T.; Nishiyama, H.; Jeyadevan, B.

    1999-07-01

    Ultra-fine magnetic particles are difficult to be dispersed in low boiling point solvents such as alcohol (C 1-C 4) and acetone. In this paper, we report the preparation methods of several alcohol and acetone-based magnetic fluids. The stability of magnetic fluid depended on the HLB (hydrophile-lipophile balance) of the solvent and alkyl chain lengths of organic layers. The fluid was most stable only when the HLB value of surfactant and the solvents are similar.

  8. The Marangoni convection induced by acetone desorption from the falling soap film

    NASA Astrophysics Data System (ADS)

    Sha, Yong; Li, Zhangyun; Wang, Yongyi; Huang, Jiali

    2012-05-01

    By means of the falling soap film tunnel and the Schlieren optical method, the Marangoni convection were observed directly in the immediate interfacial neighborhood during the desorption process of acetone from the falling soap film. Moreover, the hydraulic characteristics of the falling soap film tunnel, the acetone concentration, the surface tension of the soap liquid and the mass transfer has been investigated in details through the experimental or theoretical method.

  9. KI-catalyzed α-acyloxylation of acetone with carboxylic acids.

    PubMed

    Wu, Ya-Dong; Huang, Bei; Zhang, Yue-Xin; Wang, Xiao-Xu; Dai, Jian-Jun; Xu, Jun; Xu, Hua-Jian

    2016-07-01

    The KI-catalyzed reaction of acetone with aromatic carboxylic acids is achieved, leading to α-acyloxycarbonyl compounds in good to excellent yields under mild reaction conditions. The present method exhibits good functional-group compatibility. Notably, this reaction system is even suitable for cinnamic acid, 3-phenylpropiolic acid and 4-phenylbutanoic acid. A kinetic isotope effect (KIE) study indicates that C-H cleavage of the acetone is the rate-limiting step in the catalytic cycle. PMID:27251323

  10. Adsorption and plasma-catalytic oxidation of acetone over zeolite-supported silver catalyst

    NASA Astrophysics Data System (ADS)

    Trinh, Quang Hung; Sanjeeva Gandhi, M.; Mok, Young Sun

    2015-01-01

    The abatement of acetone using a combination of non-thermal plasma, catalysis and adsorption was investigated in a dielectric barrier discharge plasma reactor packed with silver-coated zeolite pellets serving as both adsorbent and catalyst. The removal of acetone in this reactor system was carried out by cyclic operation comprising two repetitive steps, namely, adsorption followed by plasma-catalytic oxidation. The effects of the zeolite-supported silver catalyst on the reduction of unwanted ozone emission and the behavior for the formation of gaseous byproducts were examined. The experimental results showed that the zeolite-supported catalyst had a high acetone adsorption capacity of 1.07 mmol g-1 at 25 °C. Acetone with a concentration of 300 ppm was removed from the gas stream and enriched on the zeolite surface during the adsorption step of the cyclic process (100 min). In the succeeding step, the adsorbed acetone was plasma-catalytically treated under oxygen-flowing atmosphere to recover the adsorption capability of the surface. The plasma-catalytic oxidation of the acetone adsorbed in the previous 100 min adsorption step was completed in 15 min. The abatement of acetone by the cyclic adsorption and plasma-catalytic oxidation process was able to increase the performance of the reactor with respect to the energy efficiency, compared to the case of continuous plasma-catalytic treatment. The use of the zeolite-supported silver catalyst largely decreased the emission of unreacted ozone and increased the amount of gaseous byproducts such as carbon oxides and aldehydes due to the enhanced oxidation of the adsorbed acetone and intermediates.

  11. Electrocatalytic reduction of acetone in a proton-exchange-membrane reactor: a model reaction for the electrocatalytic reduction of biomass.

    PubMed

    Green, Sara K; Tompsett, Geoffrey A; Kim, Hyung Ju; Bae Kim, Won; Huber, George W

    2012-12-01

    Acetone was electrocatalytically reduced to isopropanol in a proton-exchange-membrane (PEM) reactor on an unsupported platinum cathode. Protons needed for the reduction were produced on the unsupported Pt-Ru anode from either hydrogen gas or electrolysis of water. The current efficiency (the ratio of current contributing to the desired chemical reaction to the overall current) and reaction rate for acetone conversion increased with increasing temperature or applied voltage for the electrocatalytic acetone/water system. The reaction rate and current efficiency went through a maximum with respect to acetone concentration. The reaction rate for acetone conversion increased with increasing temperature for the electrocatalytic acetone/hydrogen system. Increasing the applied voltage for the electrocatalytic acetone/hydrogen system decreased the current efficiency due to production of hydrogen gas. Results from this study demonstrate the commercial feasibility of using PEM reactors to electrocatalytically reduce biomass-derived oxygenates into renewable fuels and chemicals. PMID:22961747

  12. Acetone and monoterpene emissions from the boreal forest in northern Europe

    NASA Astrophysics Data System (ADS)

    Janson, Robert; de Serves, Claes

    Acetone is a ubiquitous component of the atmosphere which, by its photolysis, can play an important role in photochemical reactions in the free troposphere. This paper investigates the biogenic source of acetone from Scots pine ( Pinus sylvestris) and Norway spruce ( Picea abies) in the Scandinavian boreal zone. Branch emission measurements of acetone, monoterpenes, and isoprene were made with an all-Teflon flow-through branch chamber from five specimens of Scots pine at three sites in Sweden and Finland, and from one specimen of Norway spruce at one site in Sweden. Acetone samples were taken with SepPak™ DNPH cartridges, monoterpenes with Tenax TA, and isoprene with 3 l electropolished canisters. Acetone was found to dominate the carbonyl emission of both Scots pine and Norway spruce, as large as the monoterpene emissions and for Norway spruce, as the isoprene emission. The average standard emission rate (30°C) and average β-coefficient for the temperature correlation for 5 specimens of Scots pine were 870 ng C gdw -1 h -1 (gdw=gram dry weight) and 0.12, respectively. For the monoterpenes the values were 900 ng C gdw -1 h -1 and 0.12, respectively. The standard emission rate (30°C) for acetone from Norway spruce was 265 ng C gdw -1 h -1, but the sparsity of data, along with the unusual weather conditions at the time of the measurements, precludes the establishment of a summertime best estimate emission factor.

  13. Home-made Detection Device for a Mixture of Ethanol and Acetone

    PubMed Central

    Reungchaiwat, Amnat; Wongchanapiboon, Teerapol; Liawruangrath, Saisunee; Phanichphant, Sukon

    2007-01-01

    A device for the detection and determination of ethanol and acetone was constructed, consisting of a packed column, a chamber with a sensor head, 2 dc power supplies, a multimeter and a computer. A commercially available TGS 822 detector head (Figaro Company Limited) was used as the sensor head. The TGS 822 detector consists of a SnO2 thick film deposited on the surface of an alumina ceramic tube which contains a heating element inside. An analytical column was coupled with the setup to enhance the separation of ethanol and acetone before they reached the sensor head. Optimum system conditions for detection of ethanol and acetone were achieved by varying the flow rate of the carrier gas, voltage of the heating coil (VH), voltage of the circuit sensor (VC), load resistance of the circuit sensor (RL) and the injector port temperature. The flow of the carrier gas was 15 mL/min; the circuit conditions were VH = 5.5 V, VC = 20 V, RL = 68 kΩ; and the injection port temperature was 150°C. Under these conditions the retention times (tR) for ethanol and acetone were 1.95 and 0.57 minutes, respectively. Calibration graphs were obtained for ethanol and acetone over the concentration range of 10 to 160 mg/L. The limits of detection (LOD) for ethanol and acetone were 9.25 mg/L and 4.41 mg/L respectively.

  14. Efficient encapsulation of chloroform with cryptophane-M and the formation of exciplex studied by fluorescence spectroscopy.

    PubMed

    Shi, Yanqi; Li, Xueming; Yang, Jianchun; Gao, Fang; Tao, Chuanyi

    2011-03-01

    Efficient encapsulation of small molecules with supermolecules is one of significantly important subjects due to strong application potentials. This article presents the interaction between cryptophane-M and chloroform by fluorescence spectroscopy. The sonicated cryptophane-M solution exhibits light green color in chloroform, and the solid obtained from the evaporation of chloroform also has different color from that of cryptophane-M. In contrast, the sonicated cryptophane-M solutions in other solvents are colorless, and the solid obtained from the evaporation of these solvents has the same color as that of cryptophane-M. Furthermore, the freshly prepared cryptophane-M solution in different solvents is almost colorless, and the solid obtained from the evaporation of these solvents displays the same color as that of cryptophane-M. Although the sonicated cryptophane-M solutions in different solvents have very similar absorption spectra, they exhibit quite different emission spectra in chloroform. In contrast, the freshly-prepared cryptophane-M solutions show similar absorption and emission spectroscopy in various solvents. The variation of the fluorescence spectroscopy in binary solvents with the increasing chloroform ratio suggests that cryptophane-M and chloroform form a 1:1 exciplex, and the binding constant is estimated to be 292.95 M(-1). Although all solvents are able to enter into the cavity of cryptophane-M, only chloroform can stay in the cavity of cryptophane-M for a while, which is mostly due to the strong intermolecular interaction between cryptophane-M and chloroform, and this results in the formation of the exciplex between them. PMID:20953823

  15. A study of global atmospheric budget and distribution of acetone using global atmospheric model STOCHEM-CRI

    NASA Astrophysics Data System (ADS)

    Khan, M. A. H.; Cooke, M. C.; Utembe, S. R.; Archibald, A. T.; Maxwell, P.; Morris, W. C.; Xiao, P.; Derwent, R. G.; Jenkin, M. E.; Percival, C. J.; Walsh, R. C.; Young, T. D. S.; Simmonds, P. G.; Nickless, G.; O'Doherty, S.; Shallcross, D. E.

    2015-07-01

    The impact of including a more detailed VOC oxidation scheme (CRI v2-R5) with a multi-generational approach for simulating tropospheric acetone is investigated using a 3-D global model, STOCHEM-CRI. The CRI v2-R5 mechanism contains photochemical production of acetone from monoterpenes which account for 64% (46.8 Tg/yr) of the global acetone sources in STOCHEM-CRI. Both photolysis and oxidation by OH in the troposphere contributes equally (42%, each) and dry deposition contributes 16% of the atmospheric sinks of acetone. The tropospheric life-time and the global burden of acetone are found to be 18 days and 3.5 Tg, respectively, these values being close to those reported in the study of Jacob et al. (2002). A dataset of aircraft campaign measurements are used to evaluate the inclusion of acetone formation from monoterpenes in the CRI v2-R5 mechanism used in STOCHEM-CRI. The overall comparison between measurements and models show that the parameterised approach in STOCHEM-NAM (no acetone formation from monoterpenes) underpredicts the mixing ratios of acetone in the atmosphere. However, using a detailed monoterpene oxidation mechanism forming acetone has brought the STOCHEM-CRI into closer agreement with measurements with an improvement in the vertical simulation of acetone. The annual mean surface distribution of acetone simulated by the STOCHEM-CRI shows a peak over forested regions where there are large biogenic emissions and high levels of photochemical activity. Year-long observations of acetone and methanol at the Mace Head research station in Ireland are compared with the simulated acetone and methanol produced by the STOCHEM-CRI and found to produce good overall agreement between model and measurements. The seasonal variation of model and measured acetone levels at Mace Head, California, New Hampshire and Minnesota show peaks in summer and dips in winter, suggesting that photochemical production may have the strongest effect on its seasonal trend.

  16. Nuclear magnetic resonance study of an ethyl cellulose sustained-release delivery system. I: Effect of casting solvent on hydration properties.

    PubMed

    Azoury, R; Elkayam, R; Friedman, M

    1988-05-01

    This study was conducted in order to explore the proton relaxation time and the structural features of films that are cast from different solvents and to be used as sustained-release delivery systems. Protons magnetic resonance measurements were performed on ethyl cellulose (EC) films cast from ethanol or chloroform solutions in the presence of polyethyleneglycol (PEG). Spin-lattice relaxation time (T1) was measured with a Bruker PC-20 Multispec, at 20 MHz and at 37 degrees C, on the dry films and thereafter during gradual, controlled hydration. The prolongation of the rate of relaxation time for the films cast from ethanol and chloroform solutions was found to be drastically different. Water compartmentalization was then calculated according to the Free Induction Decay model. After the addition of similar amounts of water, markedly different hydration fraction (HF) values were derived for the films cast from the different solutions as a function of the amount of embedded PEG. Scanning electron micrographs confirmed that the two types of systems have different film structures that are dictated by the casting solvent and the amount of embedded PEG. From these results it can be concluded that in the presence of PEG, EC films cast from ethanol have more water binding sites and a thicker water multilayer around them than films cast from chloroform. These properties might influence the release rate of an active agent from the sustained-release device. PMID:3411466

  17. 21 CFR 177.1320 - Ethylene-ethyl acrylate copolymers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... prescribed for polyethylene in § 177.1520. (1) Specifications—(i) Infrared identification. Ethylene-ethyl acrylate copolymers can be identified by their characteristic infrared spectra. (ii) Quantitative determination of ethyl acrylate content. The ethyl acrylate can be determined by the infrared spectra. Prepare...

  18. 21 CFR 177.1320 - Ethylene-ethyl acrylate copolymers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... § 177.1520. (1) Specifications—(i) Infrared identification. Ethylene-ethyl acrylate copolymers can be identified by their characteristic infrared spectra. (ii) Quantitative determination of ethyl acrylate content. The ethyl acrylate can be determined by the infrared spectra. Prepare a scan from 10.5 microns...

  19. 21 CFR 177.1320 - Ethylene-ethyl acrylate copolymers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... prescribed for polyethylene in § 177.1520. (1) Specifications—(i) Infrared identification. Ethylene-ethyl acrylate copolymers can be identified by their characteristic infrared spectra. (ii) Quantitative determination of ethyl acrylate content. The ethyl acrylate can be determined by the infrared spectra. Prepare...

  20. 21 CFR 177.1320 - Ethylene-ethyl acrylate copolymers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... prescribed for polyethylene in § 177.1520. (1) Specifications—(i) Infrared identification. Ethylene-ethyl acrylate copolymers can be identified by their characteristic infrared spectra. (ii) Quantitative determination of ethyl acrylate content. The ethyl acrylate can be determined by the infrared spectra. Prepare...

  1. 21 CFR 177.1320 - Ethylene-ethyl acrylate copolymers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... prescribed for polyethylene in § 177.1520. (1) Specifications—(i) Infrared identification. Ethylene-ethyl acrylate copolymers can be identified by their characteristic infrared spectra. (ii) Quantitative determination of ethyl acrylate content. The ethyl acrylate can be determined by the infrared spectra. Prepare...

  2. 40 CFR 180.441 - Quizalofop ethyl; tolerances for residues.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

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

  3. 40 CFR 180.441 - Quizalofop ethyl; tolerances for residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

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

  4. 40 CFR 180.441 - Quizalofop ethyl; tolerances for residues.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... combined residues of the herbicide quizalofop (2- propanoic acid) and quizalofop ethyl (ethyl-2- propanoate...) Tolerances are established for the combined residues of the herbicide quizalofop (2- propanoic acid... herbicide quizalofop-p ethyl ester , and its acid metabolite quizalofop-p , and the S enantiomers of...

  5. 40 CFR 180.441 - Quizalofop ethyl; tolerances for residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

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

  6. 40 CFR 180.595 - Flufenpyr-ethyl; tolerances for residues.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... residues of the herbicide, flufenpyr-ethyl; acetic acid, -phenoxy]-ethyl ester], in or on the following...) Tolerances are established for residues of the herbicide flufenpyr-ethyl; acetic acid, -phenoxy]-ethyl...

  7. 40 CFR 180.595 - Flufenpyr-ethyl; tolerances for residues.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... residues of the herbicide, flufenpyr-ethyl; acetic acid, -phenoxy]-ethyl ester], in or on the following...) Tolerances are established for residues of the herbicide flufenpyr-ethyl; acetic acid, -phenoxy]-ethyl...

  8. 40 CFR 180.595 - Flufenpyr-ethyl; tolerances for residues.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... residues of the herbicide, flufenpyr-ethyl; acetic acid, -phenoxy]-ethyl ester], in or on the following...) Tolerances are established for residues of the herbicide flufenpyr-ethyl; acetic acid, -phenoxy]-ethyl...

  9. 40 CFR 180.595 - Flufenpyr-ethyl; tolerances for residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... residues of the herbicide, flufenpyr-ethyl; acetic acid, -phenoxy]-ethyl ester], in or on the following...) Tolerances are established for residues of the herbicide flufenpyr-ethyl; acetic acid, -phenoxy]-ethyl...

  10. 40 CFR 180.595 - Flufenpyr-ethyl; tolerances for residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... residues of the herbicide, flufenpyr-ethyl; acetic acid, -phenoxy]-ethyl ester], in or on the following...) Tolerances are established for residues of the herbicide flufenpyr-ethyl; acetic acid, -phenoxy]-ethyl...

  11. Chloroform and trichloroethylene uptake from water into human skin in vitro: Kinetics and risk implications

    SciTech Connect

    Bogen, K.T.; Keating, G.A.; Vogel, J.S.

    1995-03-01

    A model recently proposed by the US Environmental Protection Agency (EPA) predicts that short-term dermal uptakes of organic environmental water contaminants are proportional to the square root of exposure time. The model appears to underestimate dermal uptake, based on very limited in vivo uptake data obtained primarily using human subjects. To further assess this model, we examined in vitro dermal uptake kinetics for aqueous organic chemicals using accelerator mass spectrometry (AMS). Specifically, we examined the kinetics of in vitro dermal uptake of {sup 14}C-labeled chloroform and trichloroethylene from dilute (5-ppb) aqueous solutions using full-thickness human cadaver skin exposed for ({le}1 hr).

  12. A novel method for measuring the concentration of chloroform based on kinetic parameters at atmosphere

    NASA Astrophysics Data System (ADS)

    Wang, Yuguo; Han, Haiyan; Chang, Tao; Liu, Xiuhong; Zhu, Qiaofen; Liu, Feng; Yan, Yongliang; Shen, Chengyin; Chu, Yannan

    2016-06-01

    A novel method is proposed to detect chloroform concentrations based on the kinetic parameters using ion mobility spectrometer with a negative corona discharge ion source operating at atmospheric pressure. Unlike conventional sample introduction mode, in this technique, CHCl3 enters into the drift tube from the end of drift region carried by the drift gas. There are two tails before Cl- and (CHCl3)·Cl- ion peaks, which fit to the ions formed in the drift region. Utilizing the kinetic parameters, concentration for CHCl3 can be calculated. This method not only offers a new way to get concentrations of CHCl3 under atmospheric pressure.

  13. [William Osler and the 'chloroforming' of men over 60: a media outcry in 1905].

    PubMed

    van Gijn, J; Nieuwkamp, D J

    2002-12-21

    Sir William Osler (1849-1919) was one of the most charismatic physicians of his generation in the English-speaking world. In 1905, in a light-hearted farewell speech at the Johns Hopkins University before leaving for Oxford, U.K., he discussed the relative uselessness of men over 60. He facetiously referred to a novel in which men above this age retired for a year of contemplation, after which they were peacefully 'chloroformed'. Osler's words were reported out of context by American newspapers and he had to put up with much indignant protest. PMID:12534103

  14. Anti-Inflammatory Effects of Hyptis albida Chloroform Extract on Lipopolysaccharide-Stimulated Peritoneal Macrophages.

    PubMed

    Sánchez Miranda, Elizabeth; Pérez Ramos, Julia; Fresán Orozco, Cristina; Zavala Sánchez, Miguel Angel; Pérez Gutiérrez, Salud

    2013-01-01

    We examined the effects of a chloroform extract of Hyptis albida (CHA) on inflammatory responses in mouse lipopolysaccharide (LPS) induced peritoneal macrophages. Our findings indicate that CHA inhibits LPS-induced production of tumor necrosis factor (TNF- α ) and interleukin-6 (IL-6). During the process, levels of cyclooxygenase-2 (COX-2), nitric oxide synthase (iNOS), and nitric oxide (NO) increased in the mouse peritoneal macrophages; however, the extract suppressed them significantly. These results provide novel insights into the anti-inflammatory actions of CHA and support its potential use in the treatment of inflammatory diseases. PMID:23970974

  15. Anti-Inflammatory Effects of Hyptis albida Chloroform Extract on Lipopolysaccharide-Stimulated Peritoneal Macrophages

    PubMed Central

    Sánchez Miranda, Elizabeth; Pérez Ramos, Julia; Fresán Orozco, Cristina; Zavala Sánchez, Miguel Angel; Pérez Gutiérrez, Salud

    2013-01-01

    We examined the effects of a chloroform extract of Hyptis albida (CHA) on inflammatory responses in mouse lipopolysaccharide (LPS) induced peritoneal macrophages. Our findings indicate that CHA inhibits LPS-induced production of tumor necrosis factor (TNF-α) and interleukin-6 (IL-6). During the process, levels of cyclooxygenase-2 (COX-2), nitric oxide synthase (iNOS), and nitric oxide (NO) increased in the mouse peritoneal macrophages; however, the extract suppressed them significantly. These results provide novel insights into the anti-inflammatory actions of CHA and support its potential use in the treatment of inflammatory diseases. PMID:23970974

  16. Production of ethyl alcohol from bananas

    SciTech Connect

    Jones, R.L.; Towns, T.

    1983-12-01

    The production of ethyl alcohol from waste bananas presents many special problems. During cooking, matting of the latex fibers from the banana peel recongeal when cooled and left untreated. This problem has been addressed by Alfaro by the use of CaC1/sub 2/. Separation of solids prior to distillation of the mashes in an economical fashion and use of the by product are also of concern to banana processors.

  17. Synthesis of Ethyl Salicylate Using Household Chemicals

    NASA Astrophysics Data System (ADS)

    Solomon, Sally; Hur, Chinhyu; Lee, Alan; Smith, Kurt

    1996-02-01

    Ethyl salicylate is synthesized, isolated, and characterized in a three-step process using simple equipment and household chemicals. First, acetylsalicylic acid is extracted from aspirin tablets with isopropyl alcohol, then hydrolyzed to salicylic acid with muriatic acid, and finally, the salicylic acid is esterified using ethanol and a boric acid catalyst. The experiment can be directed towards high school or university level students who have sufficient background in organic chemistry to recognize the structures and reactions that are involved.

  18. Computer assisted modeling of ethyl sulfate pharmacokinetics.

    PubMed

    Schmitt, Georg; Halter, Claudia C; Aderjan, Rolf; Auwaerter, Volker; Weinmann, Wolfgang

    2010-01-30

    For 12 volunteers of a drinking experiment the concentration-time-courses of ethyl sulfate (EtS) and ethanol were simulated and fitted to the experimental data. The concentration-time-courses were described with the same mathematical model as previously used for ethyl glucuronide (EtG). The kinetic model based on the following assumptions and simplifications: a velocity constant k(form) for the first order formation of ethyl sulfate from ethanol and an exponential elimination constant k(el). The mean values (and standard deviations) obtained for k(form) and k(el) were 0.00052 h(-1) (0.00014) and 0.561 h(-1) (0.131), respectively. Using the ranges of these parameters it is possible to calculate minimum and maximum serum concentrations of EtS based on stated ethanol doses and drinking times. The comparison of calculated and measured concentrations can prove the plausibility of alleged ethanol consumption and add evidence to the retrospective calculation of ethanol concentrations based on EtG concentrations. PMID:19913378

  19. The binding of ethyl isocyanide to ferroperoxidase

    PubMed Central

    Phelps, Charles; Antonini, Eraldo; Brunori, Maurizio

    1972-01-01

    The equilibrium and kinetics of ethyl isocyanide binding to ferroperoxidase were studied. At pH9.1 the results of both studies are consistent with a single-process model with an affinity constant of 95m−1 and combination and dissociation constants of 2.2×103m−1·s−1 and 23s−1 respectively. Ethyl isocyanide is not bound significantly at pH values lower than 6.0, and in this behaviour and the pH-dependence of the affinity constant, similarities exist between isocyanide and cyanide binding. The enthalpy of the process measured by equilibrium methods is −59kJ/mol (−14kcal/mol). At pH values below 9, the ethyl isocyanide adduct changes in a slow time-dependent manner, giving rise to a new species. These changes are reversible on increasing the pH. The results are discussed in relation to other known information about ligand binding to ferroperoxidase and to myoglobin. PMID:5084796

  20. Physiologically Based Pharmacokinetic modeling of the temperature-dependent dermal absorption of chloroform by humans following bath water exposures

    SciTech Connect

    Corley, Rick A. ); Gordon, Syd M.; Wallace, Lance A.

    2000-01-14

    The kinetics of chloroform in the exhaled breath of human volunteers exposed skin-only via bath water (concentrations < 100 ppb) were analyzed using a physiologically based pharmacokinetic (PBPK) model. Significant increases in exhaled chloroform (and thus bioavailability) were observed as exposure temperatures were increased from 30 to 40?C. The blood flows to the skin and effective skin permeability coefficients (Kp) were both varied to reflect the temperature-dependent changes in physiology and exhalation kinetics. At 40?C, no differences were observed between males and females. Therefore, Kp?s were determined ({approx}0.06 cm/hr) at a skin blood flow rate of 18% of the cardiac output. At 30 and 35?C, males exhaled more chloroform than females resulting in lower effective Kp?s calculated for females. At these lower temperatures, the blood flow to the skin was also reduced. Total amounts of chloroform absorbed averaged 41.9 and 43.6 mg for males and 11.5 and 39.9 mg for females exposed at 35 and 40?C, respectively. At 30?C, only 2/5 males and 1/5 females had detectable concentrations of chloroform in their exhaled breath. For perspective, the total intake of chloroform would have ranged from 79 - 194 mg if the volunteers had consumed 2 L of water orally at the concentrations used in this study. Thus, the relative contribution of dermal uptake of chloroform to the total body burdens associated with bathing for 30 min and drinking 2 L of water (ignoring contributions from inhalation exposures) was predicted to range from 1-28% depending on the temperature of the bath.

  1. 40 CFR 721.3152 - Ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

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

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

    Code of Federal Regulations, 2010 CFR

    2010-07-01

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

  3. Chemical and thermochemical aspects of the ozonolysis of ethyl oleate: decomposition enthalpy of ethyl oleate ozonide.

    PubMed

    Cataldo, Franco

    2013-01-01

    Neat ethyl oleate was ozonized in a bubble reactor and the progress of the ozonolysis was followed by infrared (FT-IR) spectroscopy and by the differential scanning calorimetry (DSC). The ozonolysis was conducted till a molar ratio O3/C=C≈1 when the exothermal reaction spontaneously went to completion. A specific thermochemical calculation on ethyl oleate ozonation has been made to determine the theoretical heat of the ozonization reaction using the group increment approach. A linear relationship was found both in the integrated absorptivity of the ozonide infrared band at 1110 cm(-1) and the ozonolysis time as well as the thermal decomposition enthalpy of the ozonides and peroxides formed as a result of the ozonation. The DSC decomposition temperature of ozonated ethyl oleate occurs with an exothermal peak at about 150-155 °C with a decomposition enthalpy of 243.0 kJ/mol at molar ratio O3/C=C≈1. It is shown that the decomposition enthalpy of ozonized ethyl oleate is a constant value (≈243 kJ/mol) at any stage of the O3/C=C once an adequate normalization of the decomposition enthalpy for the amount of the adsorbed ozone is taken into consideration. The decomposition enthalpy of ozonized ethyl oleate was also calculated using a simplified thermochemical model, obtaining a result in reasonable agreement with the experimental value. PMID:23969233

  4. Breath acetone monitoring by portable Si:WO3 gas sensors

    PubMed Central

    Righettoni, Marco; Tricoli, Antonio; Gass, Samuel; Schmid, Alex; Amann, Anton; Pratsinis, Sotiris E.

    2013-01-01

    Breath analysis has the potential for early stage detection and monitoring of illnesses to drastically reduce the corresponding medical diagnostic costs and improve the quality of life of patients suffering from chronic illnesses. In particular, the detection of acetone in the human breath is promising for non-invasive diagnosis and painless monitoring of diabetes (no finger pricking). Here, a portable acetone sensor consisting of flame-deposited and in situ annealed, Si-doped epsilon-WO3 nanostructured films was developed. The chamber volume was miniaturized while reaction-limited and transport-limited gas flow rates were identified and sensing temperatures were optimized resulting in a low detection limit of acetone (~20 ppb) with short response (10–15 s) and recovery times (35–70 s). Furthermore, the sensor signal (response) was robust against variations of the exhaled breath flow rate facilitating application of these sensors at realistic relative humidities (80–90%) as in the human breath. The acetone content in the breath of test persons was monitored continuously and compared to that of state-of-the-art proton transfer reaction mass spectrometry (PTR-MS). Such portable devices can accurately track breath acetone concentration to become an alternative to more elaborate breath analysis techniques. PMID:22790702

  5. Exploration of detection sensitivity of biomarker acetone in aqueous samples using cavity ringdown spectroscopy

    NASA Astrophysics Data System (ADS)

    Mbi, Armstrong; Wang, Chuji

    2007-03-01

    Breath acetone is a biomarker for diabetes (Type 1). Currently, high sensitivity breath gas analysis is mainly performed by gas chromatography-mass spectrometry (GC-MC). We are developing a potable ringdown spectrometer for diabetes diagnostics using non-invasive breath gas analysis. The ringdown spectrometer consists of a compact Nd: YAG laser source operating at 266 nm, a atmospheric gas cell of 43 cm in length, a miniature detector, and a data processing section. In this work, the exploration of detection sensitivity of acetone in aqueous samples using cavity ringdown spectroscopy is presented. Pure acetone is diluted in distilled water in different concentrations ranging from 0.5 drop/liter to 8 drops/liter, or 730 ppbv - 12 ppmv in gas phase. The instrument performance using two sampling methods is evaluated. With the mirror reflectivity of 99.98%, the spectrometer demonstrates a detection limit of acetone of 450 ppbv (based on 1-σ), which is slightly lower than the threshold number of acetone concentration in normal human breath. Preliminary results from actual breath gases are also presented.

  6. Detection of Acetone Processing of Castor Bean Mash for Forensic Investigation of Ricin Preparation Methods

    SciTech Connect

    Kreuzer-Martin, Helen W.; Wahl, Jon H.; Metoyer, Candace N.; Colburn, Heather A.; Wahl, Karen L.

    2010-07-01

    The toxic protein ricin is of concern as a potential biological threat agent (BTA) Recently, several samples of ricin have been seized in connection with biocriminal activity. Analytical methods are needed that enable federal investigators to determine how the samples were prepared, to match seized samples to potential source materials, and to identify samples that may have been prepared by the same method using the same source materials. One commonly described crude ricin preparation method is acetone extraction of crushed castor beans. Here we describe the use of solid-phase microextraction and headspace analysis of crude ricin preparation samples to determine whether they were processed by acetone extraction. In all cases, acetone-extracted bean mash could be distinguished from un-extracted mash or mash extracted with other organic solvents. Statistical analysis showed that storage in closed containers for up to 109 days had no effect on acetone signal intensity. Signal intensity in acetone-extracted mash decreased during storage in open containers, but extracted mash could still be distinguished from un-extracted mash after 94 days.

  7. Destruction of acetone using a small-scale arcjet plasma torch

    SciTech Connect

    Snyder, H.R.; Fleddermann, C.B.; Gahl, J.M.

    1996-12-31

    A small-scale thermal plasma torch has been constructed to determine the feasibility of its use to dispose of hazardous solvent wastes. The system has been studied using acetone as a test compound. The plasma jet is generated using argon and a commercial AC/DC welding supply. The system is operated using torch currents ranging from 50 to 200 A and solvent flow rates in the range 0--200 ml/h. Oxygen is added to alter the chemistry occurring in the reaction chamber. The destruction of acetone and the relative amounts of the reaction by-products are monitored using a residual gas analyzer. The pyrolysis products consist primarily of CO, CH{sub 4}, C{sub 2}H{sub 2}, C{sub 2}H{sub 4}, and other C{sub x}H{sub y} radicals when no oxygen is added to the system. By adding oxygen to the system, thermal oxidation processes occur that increase the production of CO{sub 2} and significantly decrease the amount of acetone in the exhaust gases. This paper includes data on the destruction efficiency of acetone as a function of solvent flow rate, torch power, argon flow rate and oxygen injection rate. The results indicate that greater than 99% destruction efficiency of acetone can be achieved with addition of oxygen to the reaction mixture using an arcjet current of 75 A.

  8. Field Demonstration of Acetone Pretreatment and Composting of Particulate-TNT-Contaminated Soil

    SciTech Connect

    Radtke, Corey William; Smith, D.; Owen, S.; Roberto, Francisco Figueroa

    2002-02-01

    Solid fragments of explosives in soil are common in explosives testing and training areas. In this study we initially sieved the upper 6 in of contaminated soil through a 3-mm mesh, and found 2, 4, 6-trinitrotoluene (TNT) fragments. These contributed to an estimated concentration of 1.7 kg per cubic yard soil, or for 2000 ppm TNT in the soil. Most of the fragments ranged 4 mm to 10 mm diameter in size, but explosives particles weighing up to 56 g (about 4 cm diameter) were frequently observed. An acetone pretreatment/composting system was then demonstrated at field scale. The amount of acetone required for a TNT-dissolving slurry process was controlled by the viscosity of the soil/acetone mix rather than the TNT dissolution rate. The amount needed was estimated at about 55 gallons acetone per cubic yard soil. Smaller, 5- to 10-mm-diameter fragments went into solution in less than 15 min at a mixer speed of 36 rpm, with a minimum of 2 g TNT going into solution per 30 min for the larger chunks. The slurries were than mixed with compost starting materials and composted in a vented 1 yd3 container. After 34 days incubation time TNT was below the site-specific regulatory threshold of 44 ppm. TNT metabolites and acetone were also below their regulatory thresholds established for the site.

  9. The Reactions of Acetone with the Surfaces of Uranium Dioxide Single Crystal and Thin Film

    SciTech Connect

    King,R.; Senanayake, S.; Chong, S.; Idriss, H.

    2007-01-01

    The reaction of acetone, as an example of a carbonyl compound, is studied over UO2 (1 1 1) single crystal and thin film surfaces. Over the stoichiometric single crystal surface, acetone is molecularly and weakly adsorbed with a computed activation energy for desorption in the range of 95-65 kJ/mol with pre-exponential factors between 1011 and 1013 s-1. On the contrary, acetone reacts very strongly on the O-defected single crystal and thin film surfaces. In addition to total decomposition evidence of aldolization and cyclization reactions were seen. The thin film of UO2 was studied by synchrotron light, providing high resolution photoelectron spectroscopy in the core level, and high sensitivity in the both the core and valence band regions. The U5f line was considerably enhanced at grazing angle when compared to that obtained at normal angle for the O-defected surface, showing that the surface is more reduced than the next layers. The U 4f lines indicated the presence of U cations in lower oxidation states than +4 for the O-defected surface. These lines were considerably attenuated upon adsorption of acetone, due to surface oxidation by C{double_bond}O bond dissociation. The reaction pathway for acetone on the O-defected surface is presented, and compared to that of the previously studied acetaldehyde molecule.

  10. Efficient acetone-butanol-ethanol production by Clostridium beijerinckii from sugar beet pulp.

    PubMed

    Bellido, Carolina; Infante, Celia; Coca, Mónica; González-Benito, Gerardo; Lucas, Susana; García-Cubero, María Teresa

    2015-08-01

    Sugar beet pulp (SBP) has been investigated as a promising feedstock for ABE fermentation by Clostridium beijerinckii. Although lignin content in SBP is low, a pretreatment is needed to enhance enzymatic hydrolysis and fermentation yields. Autohydrolysis at pH 4 has been selected as the best pretreatment for SBP in terms of sugars release and acetone and butanol production. The best overall sugars release yields from raw SBP ranged from 66.2% to 70.6% for this pretreatment. The highest ABE yield achieved was 0.4g/g (5.1g/L of acetone and 6.6g/L butanol) and 143.2g ABE/kg SBP (62.3g acetone and 80.9g butanol) were obtained when pretreated SBP was enzymatically hydrolyzed at 7.5% (w/w) solid loading. Higher solid loadings (10%) offered higher acetone and butanol titers (5.8g/L of acetone and 7.8g/L butanol). All the experiments were carried out under not-controlling pH conditions reaching about 5.3 in the final samples. PMID:25965949

  11. Design, synthesis, molecular docking studies and in vitro screening of ethyl 4-(3-benzoylthioureido) benzoates as urease inhibitors.

    PubMed

    Saeed, Aamer; Khan, Muhammad Siraj; Rafique, Hummera; Shahid, Mohammad; Iqbal, Jamshed

    2014-02-01

    Thioureas are exceptionally versatile building blocks towards the synthesis of wide variety of heterocyclic systems, which also possess extensive range of pharmacological activities. The substituted benzoic acids were converted into corresponding acid chlorides, these acid chlorides were then treated with potassium thiocyanate in acetone and then the reaction mixture was refluxed for 1-2h afford ethyl 4-(3-benzoylthioureido)benzoates thioureas in good yields. All the newly synthesized compounds were evaluated for their urease inhibitory activities and were found to be potent inhibitors of urease enzyme. Compounds 1f and 1g were identified as the most potent urease inhibitors (IC50 0.21 and 0.13 μM, respectively), and was 100-fold more potent than the standard inhibitors. Further molecular docking studies were carried out using the crystal structure of urease to find out the binding mode of the inhibitors with the enzyme. PMID:24269986

  12. Influence of Sulfur for Oxygen Substitution in the Solvolytic Reactions of Chloroformate Esters and Related Compounds

    PubMed Central

    D’Souza, Malcolm J.; Kevill, Dennis N.

    2014-01-01

    The replacement of oxygen within a chloroformate ester (ROCOCl) by sulfur can lead to a chlorothioformate (RSCOCl), a chlorothionoformate (ROCSCl), or a chlorodithioformate (RSCSCl). Phenyl chloroformate (PhOCOCl) reacts over the full range of solvents usually included in Grunwald-Winstein equation studies of solvolysis by an addition-elimination (A-E) pathway. At the other extreme, phenyl chlorodithioformate (PhSCSCl) reacts across the range by an ionization pathway. The phenyl chlorothioformate (PhSCOCl) and phenyl chlorothionoformate (PhOCSCl) react at remarkably similar rates in a given solvent and there is a dichotomy of behavior with the A-E pathway favored in solvents such as ethanol-water and the ionization mechanism favored in aqueous solvents rich in fluoroalcohol. Alkyl esters behave similarly but with increased tendency to ionization as the alkyl group goes from 1° to 2° to 3°. N,N-Disubstituted carbamoyl halides favor the ionization pathway as do also the considerably faster reacting thiocarbamoyl chlorides. The tendency towards ionization increases as, within the three contributing structures of the resonance hybrid for the formed cation, the atoms carrying positive charge (other than the central carbon) change from oxygen to sulfur to nitrogen, consistent with the relative stabilities of species with positive charge on these atoms. PMID:25310653

  13. Chloroformic and Methanolic Extracts of Olea europaea L. Leaves Present Anti-Inflammatory and Analgesic Activities

    PubMed Central

    Chebbi Mahjoub, R; Khemiss, M.; Dhidah, M.; Dellaï, A.; Bouraoui, A.; Khemiss, F.

    2011-01-01

    Olea europaea L. is used in traditional medicine in the Mediterranean areas. Its natural products are used in the treatment of different disorders, like fighting fever and some infectious diseases such as malaria, the treatment of arrhythmia, and relief of intestinal spasms. The aim of the current study is to investigate the possible anti-inflammatory and anatinociceptive effects of methanol and chloroformic extracts prepared from leaves of Olea europaea L. The anti-inflammatory and antinociceptive effects of the different extracts of Olea europaea leaves were assessed after intraperitoneal administration into rats and mice, using the carrageenan-induced paw edema model in rats to test the anti-inflammatory effect and the acetic acid-induced writhing in mice to test the analgesic effect. The chloroformic and methanolic leaves extracts, studied at the doses of 50, 100, and 200 mg/kg (Body Weight: BW), exhibited significant dose-dependent anti-inflammatory and analgesic activities. Based on the results obtained, it can be concluded that Olea europaea leaves extracts have anti-inflammatory and antinociceptive effects. PMID:22084717

  14. Project Work Plan Carbon Tetrachloride and Chloroform Attenuation Parameter Studies: Heterogeneous Hydrolytic Reactions

    SciTech Connect

    Amonette, James E.; Truex, Michael J.; Fruchter, Jonathan S.

    2006-06-01

    Between 1955 and 1973, an estimated 750,000 kg of carbon tetrachloride were discharged to the soil in the 200 West Area of the Hanford Site as part of the plutonium production process. Of this amount, some carbon tetrachloride reached the groundwater more than 70 m below the ground surface and formed a plume of 10 km2. Recent information has shown that the carbon tetrachloride plume extends to a depth of at least 60 m below the water table. Some carbon tetrachloride has been degraded either by the original process or subsequent transformations in the subsurface to form a co-existing chloroform plume. Although current characterization efforts are improving the conceptual model of the source area, more information is needed to effectively assess the fate and transport of carbon tetrachloride and chloroform to support upcoming remediation decisions for the plume. As noted in a simulation study by Truex et al. (2001), parameters describing porosity, sorption, and abiotic degradation have the largest influence on predicted plume behavior. The work proposed herein will improve the ability to predict future plume movement by better quantifying abiotic degradation mechanisms and rates. This effort will help define how much active remediation may be needed and estimate where the plume will eventually stabilize – key factors in determining the most appropriate remedy for the plume.

  15. Abiotic Degradation Rates for Carbon Tetrachloride and Chloroform: Progress in FY 2010

    SciTech Connect

    Amonette, James E.; Jeffers, Peter M.; Qafoku, Odeta; Russell, Colleen K.; Humphrys, Daniel R.; Wietsma, Thomas W.; Truex, Michael J.

    2010-12-08

    This report documents the progress made through FY 2010 on a project initiated in FY 2006 to help address uncertainties related to the rates of hydrolysis in groundwater at the Hanford Site for carbon tetrachloride (CT) and chloroform (CF). The study also explores the possible effects of contact with minerals and sediment (i.e., heterogeneous hydrolysis) on these rates. The research was initiated to decrease the uncertainties in abiotic degradation rates of CT and chloroform CF associated with temperature and possible heterogeneous effects. After 2 years of data collection, the first evidence for heterogeneous effects was identified for hydrolysis of CT, and preliminary evidence for the effects of different mineral types on CF hydrolysis rates also was reported. The CT data showed no difference among mineral types, whereas significant differences were seen in the CF results, perhaps due to the fact that CF hydrolyzes by both neutral and base-catalyzed mechanisms whereas CT follows only the neutral hydrolysis path. In this report, we review the project objectives, organization, and technical approaches taken, update the status and results of the hydrolysis-rate experiments after 4 years of experimentation (i.e., through FY 2010), and provide a brief discussion of how these results add to scientific understanding of the behavior of the CT/CF plume at the Hanford Site.

  16. Role of chloroform and dichloromethane solvent molecules in crystal packing: an interaction propensity study.

    PubMed

    Allen, Frank H; Wood, Peter A; Galek, Peter T A

    2013-08-01

    Using the Cambridge Structural Database (CSD), it is shown that the acidic C-H donors of chloroform and dichloromethane, respectively, form hydrogen bonds with N, O, S, halides or carbon-bound halogens in 82% and 77% of structures in which such interactions can occur. This hydrogen-bond potency is retained to a significant degree even in the presence of the more conventional O-H and N-H donors. The hydrogen-bond propensities exhibited by the C-H protons in CHCl3 and CH2Cl2 are similar to those of the acetylenic C-C≡C-H proton. However, involvement of the Cl atoms of CHCl3 and CH2Cl2 in non-bonded interactions is rather limited: the propensities for formation of (O or N)-H...Cl bonds are only 6% in both cases, while the propensities for the formation of halogen-halogen bonds is generally < 15%, with only Cl...Br interactions having slightly higher values. While C(phenyl)-H...Cl interactions are commonly observed, they are of low propensity and have distances at the upper end of the van der Waals limit. We conclude that the acidic C-H protons in chloroform and dichloromethane solvent molecules play a clear role in the involvement of these molecules in molecular aggregation in crystal structures, and this is exemplified by hydrogen-bond predictions made using the statistical propensity tool which is now part of the CSD system. PMID:23873063

  17. Influence of Ultrasonic Irrigation and Chloroform on Cleanliness of Dentinal Tubules During Endodontic Retreatment-An Invitro SEM Study

    PubMed Central

    Singhal, Anurag; Gurtu, Anuraag; Vinayak, Vineet

    2015-01-01

    Background Ultrasonic irrigation has been proved for its remarkable cleaning efficiency in the field of endodontics. But its role in endodontic re-treatment has been understated. There is not much data available to understand the effect of ultrasonic irrigation for the evaluation of cleanliness of dentinal tubules when it is used with or without chloroform, a gutta percha solvent during endodontic retreatment. Aim To compare the influence of ultrasonic irrigation with syringe irrigation on cleanliness of dentinal tubules after gutta perch removal for endodontic retreatment with or without the use of chloroform a gutta percha solvent using scanning electron microscope (SEM). Materials and Methods Freshly extracted 45 human mandibular premolar teeth for periodontal and orthodontic reasons were taken and were occlusally adjusted to a working length of 19 mm. The root canals of all teeth were prepared chemo mechanically to a master apical file size 40 and were divided in various groups. In Group 1 (n = 5; control group), the canals remained unfilled. In Groups 2 and 3 (n = 20 each), the canals were filled using lateral compaction with gutta-percha and AH plus sealer, removal of root fillings was undertaken after 2 weeks using Gates Glidden drills and H files without chloroform in Group 2 and with chloroform in group 3. The specimen of Group 2 and 3 were further divided into two subgroups I and II (n=10). In subgroup I, irrigation was done using side vented needles and sodium hypochlorite. In subgroup II irrigation was done using passive ultrasonic irrigation with sodium hypochlorite. Thereafter, the roots were split and the sections were observed under SEM. The number of occluded dentinal tubules /total number of dentinal tubules were calculated for the coronal, middle and apical third of each root half. Statistical analysis was performed using one-way ANOVA followed by Tukey’s test using standardized technique. Result Results indicated that the cleanest dentinal

  18. [Kenzo Yoshida of the Hiroshima Domain and Chloroform Anesthesia at the End of the Edo Era in Japan].

    PubMed

    Matsuiki, Akitomo

    2016-02-01

    Japanese physicians encountered difficulties in obtaining information from The Netherlands on general anesthetics since 1848. It was a turning point when Chinese medical textbooks were imported in the latter half of the 1850 s. They were written by Benjamin Hobson (1816-1873), a British missionary and physician who lived in China for many years. Among them, Siyi Luelun (Sei-i Ryakuron) published in 1857, was widely welcome by Japanese surgeons and medical students. Kenzo Yoshida (1848-1924), a physician from the Hiroshima Domain, was impressed by a two-page description of chloroform anesthesia in it He observed William Willis administrating chloroform anesthesia on several injured Satsuma domain soldiers in January 1868 at the Shokokuji Temple in Kyoto. A few days later, Yoshida had a chance to administer chloroform to a man who committed suicide by cutting the abdomen. The intestine, which was 90 cm long, protruded from the wound, was put back into the abdominal cavity under chloroform anesthesia given by Yoshida. This is the second case of chloroform anesthesia administered by a Japanese physician. PMID:27017783

  19. Characterization and acetone gas sensing properties of electrospun TiO2 nanorods

    NASA Astrophysics Data System (ADS)

    Bian, Haiqin; Ma, Shuyi; Sun, Aimin; Xu, Xiaoli; Yang, Guijin; Gao, Jiming; Zhang, Zhengmei; Zhu, Haibin

    2015-05-01

    In this work, random network structure of titanium dioxides (TiO2) nanorods was synthesized by calcining electrospun TiO2/PVP hybrid rods. Structural, optical and acetone gas sensing properties of the nanorods were investigated. The TiO2 nanorods are polycrystalline with a mixture of anatase and rutile structures. The diameter of TiO2 nanorods is about 500 nm. The photoluminescence (PL) spectra measurement at room temperature revealed that a broad emission band including the two emission peaks are about at 401 and 467 nm. The sensor shows the high response, good reproducibility and selectivity for acetone (CH3COCH) with a fast response and recovery time at 500 °C. In addition, the acetone sensing mechanism of the TiO2 nanorods sensors is discussed.

  20. Structural study of a zinc(II) complex with acetone 3-hexamethyleneiminylthiosemicarbazone

    NASA Astrophysics Data System (ADS)

    Castiñeiras, Alfonso; West, Douglas X.

    2002-02-01

    The crystal structure of a zinc complex with acetone 3-hexamethyleneiminylthiosemicarbazone has been determined and contains two anionic thiosemicarbazone ligands prepared from acetone. Bis(acetone 3-hexamethyleneiminylthiosemicarbazone)zinc(II), [Zn(Acehexim) 2], crystallizes monoclinic, P2 1/ c, a=8.406(3), b=13.518(5), c=22.136(3) Å, β=100.61(3), V=2472.3(12) Å3, Z=4. The distortion from tetrahedral symmetry, while substantial, is less than found for other 4-coordinate zinc complexes with bulkier thiosemicarbazone ligands. The largest angle, S-Zn-S, is 126.44(14)° and the smallest angle, 87.1(3)°, is the average of the chelating N-Zn-S angles. The angle between the mean planes of the two chelate rings is 79.41(21)°. Disorder within the hexamethyleneiminyl rings, which is common for this function, causes a larger than desired R-value.

  1. Acetone Sensing Properties of a Gas Sensor Composed of Carbon Nanotubes Doped With Iron Oxide Nanopowder

    PubMed Central

    Tan, Qiulin; Fang, Jiahua; Liu, Wenyi; Xiong, Jijun; Zhang, Wendong

    2015-01-01

    Iron oxide (Fe2O3) nanopowder was prepared by a precipitation method and then mixed with different proportions of carbon nanotubes. The composite materials were characterized by X-ray powder diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. A fabricated heater-type gas sensor was compared with a pure Fe2O3 gas sensor under the influence of acetone. The effects of the amount of doping, the sintering temperature, and the operating temperature on the response of the sensor and the response recovery time were analyzed. Experiments show that doping of carbon nanotubes with iron oxide effectively improves the response of the resulting gas sensors to acetone gas. It also reduces the operating temperature and shortens the response recovery time of the sensor. The response of the sensor in an acetone gas concentration of 80 ppm was enhanced, with good repeatability. PMID:26569253

  2. Development of UV-ionization based trace differential mobility sensor for acetone and hexane.

    PubMed

    Suresh, M; Vasa, Nilesh J; Agarwal, Vivek; Chandapillai, Jacob

    2014-01-01

    Clinical studies in recent times confirm feasibility of using trace concentrations of volatile organic compounds (VOC) in human exhale air as potential bio-markers for a variety of disease states. A Differential Mobility Sensor (DMS) with dual ultra-violet (UV) photo-ionization source is proposed and demonstrated for measurement of trace amounts of VOC gases in human exhale air. Experimental work performed with the DMS using high frequency asymmetrical waveform field for detection of trace concentrations of acetone and hexane with a few carrier gases including air, CO2 and O2 is discussed. The detection limit as estimated for Signal to Noise Ratio (SNR) of 3 is of the order of sub ppm levels for acetone and hexane. Experimental studies clearly demonstrate selective sensing of a gas in a mixture of gases by applying appropriate compensation field. Preliminary study on sensing of acetone in human breath shows good a correlation with blood glucose measurements. PMID:25570739

  3. High-sensitivity detection of triacetone triperoxide (TATP) and its precursor acetone

    NASA Astrophysics Data System (ADS)

    Dunayevskiy, Ilya; Tsekoun, Alexei; Prasanna, Manu; Go, Rowel; Patel, C. Kumar N.

    2007-09-01

    Triacetone triperoxide (C9H18O6, molecular mass of 222.24 g/mol) (TATP) is a powerful explosive that is easy to synthesize using commonly available household chemicals, acetone, and hydrogen peroxide 1 2. Because of the simplicity of its synthesis, TATP is often the explosive of choice for terrorists, including suicide bombers. For providing safety to the population, early detection of TATP and isolation of such individuals are essential. We report unambiguous, high-sensitivity detection of TATP and its precursor, acetone, using room-temperature quantum cascade laser photoacoustic spectroscopy (QCL-PAS). The available sensitivity is such that TATP, carried on a person (at a nominal body temperature of 37 °C), should be detectable at some distance. The combination of demonstrated detection of TATP and acetone should be ideal for screening at airports and other public places for providing increased public safety.

  4. The chemistry of acetone at extreme conditions by density functional molecular dynamics simulations.

    PubMed

    Ferrante, Francesco; Lo Celso, Fabrizio; Triolo, Roberto; Taleyarkhan, Rusi P

    2011-02-14

    Density functional molecular dynamics simulations have been performed in the NVT ensemble (moles (N), volume (V) and temperature (T)) on a system formed by ten acetone molecules at a temperature of 2000 K and density ρ = 1.322 g cm(-3). These conditions resemble closely those realized at the interface of an acetone vapor bubble in the early stages of supercompression experiments and result in an average pressure of 5 GPa. Two relevant reactive events occur during the simulation: the condensation of two acetone molecules to give hexane-2,5-dione and dihydrogen and the isomerization to the enolic propen-2-ol form. The mechanisms of these events are discussed in detail. PMID:21322700

  5. Thermal Z,E-isomerization of imines. IV. Anils of acetone

    SciTech Connect

    Prosyanik, A.V.; Kol'tsov, N.Yu.; Romanchenko, V.A.

    1986-12-20

    It has been established by the correlation between the values of log k/sub 298/ and the sigma constants that the degenerate thermal Z,E-isomerization of anils of acetone takes place according to an inversion mechanism, with the exception of acetone p-dimethylaminophenylimine, which isomerizes predominantly according to a rotation mechanism. The increase in the steric stresses upon the introduction of ortho substituents into the aryl ring of anils of acetone results in significant lowering of the barriers to the inversion of the nitrogen atom. The raising of the barriers to inversion in phenylimines as the electron-acceptor properties of the substituents on the imino carbon atom are enhanced is due to the weakening of the n/sub ..pi../N-..pi../sub Ph/* interaction as a consequence of the increase in the energy gap between the interacting orbitals as a result of the lowering of the energy of the n/sub ..pi../N orbital.

  6. Designing and creating a modularized synthetic pathway in cyanobacterium Synechocystis enables production of acetone from carbon dioxide.

    PubMed

    Zhou, Jie; Zhang, Haifeng; Zhang, Yanping; Li, Yin; Ma, Yanhe

    2012-07-01

    Ketones are a class of important organic compounds. As the simplest ketone, acetone is widely used as solvents or precursors for industrial chemicals. Presently, million tonnes of acetone is produced worldwide annually, from petrochemical processes. Here we report a biotechnological process that can produce acetone from CO(2), by designing and creating a modularized synthetic pathway in engineered cyanobacterium Synechocystis sp. PCC 6803. The engineered Synechocystis cells are able to produce acetone (36.0 mgl(-1) culture medium) using CO(2) as the sole carbon source, thus opens the gateway for biosynthesis of ketones from CO(2). PMID:22475865

  7. Acetone reactions over the surfaces of polycrystalline UO2: a kinetic and spectroscopic study.

    PubMed

    King, Richard; Idriss, Hicham

    2009-04-21

    The reaction of acetone is studied on the surfaces of polycrystalline UO2, prepared by hydrogen reduction of U3O8 at 770 K. The study is conducted by in situ Fourier transform infrared (FTIR) and temperature-programmed desorption (TPD). Acetone adsorption does not fit the simple Langmuir model, and adsorbate-adsorbate interactions are found to be significant. Acetone adsorbs molecularly on UO2 as evidenced by the nuCO of the eta1(O) mode at 1686 cm(-1). Part of acetone is reduced to the isopropoxide species ((CH3)2HC-O-U4+) upon heating (nu(CC), rho(CH3) at 1167 cm(-1) and nu(CO), rho(CH3) at 980 cm(-1)), and upon further heating, acetates (CH3COO(a), (a) for adsorbed) are observed. Detailed TPD studies indicated that the main reaction of acetone on UO2 is the deoxygenation to propene, driven by the oxophilic nature of UO2. Other reactions were also observed to a lesser extent, and these included reductive coupling to 2,3-dimethylbutene and condensation to mesityl oxide. An attempt to extract kinetic parameters from TPD data was conducted. Three models were studied: variation of heating rate, leading edge analysis (Habenschaden-Kuppers method), and complete analysis. The complete analysis provided the most plausible results, in particular, at low coverage. With this method, at nearly zero coverage the activation energy, Ed, for desorption was found to be close to 140 kJ/mol with a prefactor of 10(13) s(-1). Ed dropped sharply with increasing coverage, theta, to ca. 35 kJ/mol at theta=0.15 with a prefactor of 10(11) s(-1). The activation energy for the desorption of acetone on UO2(111) single crystals, at saturation coverage, was previously found to be equal to 65 kJ/mol using the leading edge analysis. PMID:19366223

  8. Measurement of natural carbon isotopic composition of acetone in human urine.

    PubMed

    Yamada, Keita; Ohishi, Kazuki; Gilbert, Alexis; Akasaka, Mai; Yoshida, Naohiro; Yoshimura, Ryoko

    2016-02-01

    The natural carbon isotopic composition of acetone in urine was measured in healthy subjects using gas chromatography-combustion-isotope ratio mass spectrometry combined with headspace solid-phase microextraction (HS-SPME-GC-C-IRMS). Before applying the technique to a urine sample, we optimized the measurement conditions of HS-SPME-GC-C-IRMS using aqueous solutions of commercial acetone reagents. The optimization enabled us to determine the carbon isotopic compositions within ±0.2 ‰ of precision and ±0.3‰ of error using 0.05 or 0.2 mL of aqueous solutions with acetone concentrations of 0.3-121 mg/L. For several days, we monitored the carbon isotopic compositions and concentrations of acetone in urine from three subjects who lived a daily life with no restrictions. We also monitored one subject for 3 days including a fasting period of 24 h. These results suggest that changes in the availability of glucose in the liver are reflected in changes in the carbon isotopic compositions of urine acetone. Results demonstrate that carbon isotopic measurement of metabolites in human biological samples at natural abundance levels has great potential as a tool for detecting metabolic changes caused by changes in physiological states and disease. Graphical abstract The natural carbon isotopic composition of acetone in urine can be determined using HS-SPME-GCC-IRMS and can provide information on changes in the availability of glucose in the liver. PMID:26718914

  9. Relationship of O2 Photodesorption in Photooxidation of Acetone on TiO2

    SciTech Connect

    Henderson, Michael A.

    2008-07-31

    Organic photooxidation on TiO2 invariably involves the coexistence of organic species with oxygen on the surface at the same time. In the case of acetone and oxygen, both species exhibit their own interesting photochemistry on TiO2, but interdependences between the two are not understood. In this study, a rutile TiO2(110) surface possessing 7% surface oxygen vacancy sites is used as a model surface to probe the relationship between O2 photodesorption and acetone photodecomposition. Temperature programmed desorption (TPD) and photon stimulated desorption (PSD) measurements indicate that coadsorbed oxygen is essential to acetone photodecomposition on this surface, however the form of oxygen (molecular and dissociative) is not known. The first steps in acetone photodecomposition on TiO2(110) involve thermal activation with oxygen to form an acetone diolate ((CH3)2COO) species followed by photochemical decomposition to adsorbed acetate (CH3COO) and an ejected CH3 radical that is detected in PSD. Depending on the surface conditions, O2 PSD is also observed during the latter process. However, the time scales for the two PSD events (CH3 and O2) are quite different, withthe former occurring at ~10 times faster than the latter. By varying the preheating conditions or performing pre-irradiation on an O2 exposed surface, it becomes clear that the two PSD events are uncorrelated. That is, the O2 species responsible for O2 PSD is not a significant participant in the photochemistry of acetone on TiO2(110) and likely originates from a minority form of O2 on the surface. The CH3 and O2 PSD events do not appear to be in competition with each other suggesting either that ample charge carriers exist under the experimental conditions employed or that different charge carriers or excitation mechanisms are involved.

  10. Direct solid-support sample loading for fast cataluminescence determination of acetone in human plasma.

    PubMed

    Yang, Ping; Lau, Choiwan; Liu, Xia; Lu, Jianzhong

    2007-11-15

    In the current manuscript we describe the development of a novel cataluminescence (CTL) sensor coupled with ionic liquids (ILs)-based headspace solid-phase microextraction (HS-SPME) technologies for the quantification of human plasma acetone levels associated with diabetic disease ex vivo. The unique properties of ILs, such as their nonvolatile and nonflammable nature, coupled with their high thermal stability allow ILs to be conveniently adopted as pseudosolid carriers for direct loading of acetone into a CTL sensor without matrix interference. Acetone from diabetic patient plasma and plasma samples spiked with acetone along with methanol, ethanol, and formaldehyde was conveniently and rapidly extracted and enriched in 3 microL of IL and then rapidly quantified by our CTL sensor. The presence of plasma alone or spiked plasma containing methanol, ethanol, or formaldehyde did not interfere with acetone measurements. HS-SPME-CTL provides higher enrichment efficiency than headspace single-drop microextraction-based CTL (HS-SDME-CTL) methods, possibly due to that the thin film formed in HS-SPME instead of the single IL drop in HS-SDME increases the exchange area for extracted acetone. The enrichment efficiency by HS-SPME-CTL was almost 80-fold higher than that with direct injection using the same volume of aqueous samples and more than 6-fold higher than that using HS-SDME-CTL. Considering that ILs can be easily prepared from inexpensive materials and tuned by the combination of different anions and cations for the extraction of specific analytes from various solvent media, this proposed technology raises an exciting possibility by employing HS-SPME-CTL for the fast determination of specific targets in many fields. PMID:17939643

  11. Binderless briquetting of coal powders by an acetone treatment process. [MS Thesis

    SciTech Connect

    Fields, G.L.

    1982-07-01

    The results of an experimental investigation of a binderless briquetting process are presented. The process involves the use of a solvent treatment step instead of using a conventional binder, and can produce water-resistant briquettes of high durability from high volatile C bituminous coals. The effectiveness of several types of solvents was determined as well as varying conditions of treatment and pressing. Treatment conditions of solvent to coal ratios, contact time, solvent temperature, and coal moisture were studied, as well as pressing conditions of temperature, pressure and coal moisture. The ketones were the most effective of the solvents studied and acetone was given the most attention due to its low cost, recoverability and fast solvent action. The optimum treatment conditions are to treat dry coal powders with acetone on a 1 to 1 weight basis for 60 sec. The acetone can be evaporated off the coal at room temperature or in an oven at 110/sup 0/C. The acetone may also be removed by leaching with water and recovered through distillation. Wet coal powders can also be treated if the moisture level is kept below 15 to 20%. The optimum pressing conditions were determined for acetone treated powders that were briquetted with a Buehler Specimen Mount laboratory press. The conditions are a pressure of 10,000 to 12,000 psi, a temperature of 150/sup 0/C, a pressing time of 5 min, and a coal moisture level of less than 5%. Briquettes made from acetone treated coal powders demonstrated superior resistance to water penetration and degradation. The process has potential for scale-up to an industrial size by using a roll-press briquetter.

  12. The Reaction Mechanism of Decomposing Chloroform by Bi-Metal Nano-Metallic Particles of Fe/Ni

    SciTech Connect

    Hsieh, Su-Hwei; Horng, Jao-Jia

    2004-03-31

    By adding Ni into the production of Fe/Ni nano-metallic particles, the acceleration of reduction ability of particles to decompose Chloroform is observed. The addition also could inhibit the shielding effect of pure iron compounds. This research studied the production and properties of the nano-particle metallic compounds of Fe and Ni, the decomposition of Chloroform by the particles and the mechanism of the decomposition processes. The experimental results indicated effective and rapid decomposition of chloroform by the Fe/Ni nano-particles on aluminum oxides, comparing to nano particles of iron in other researches. The reaction mechanism of Fe/Ni particles was pseudo first order with the half life about 0.7 hour, which was much shorter than the nano-Fe particles.

  13. Acute Toxicity Investigation and Anti-diarrhoeal Effect of the Chloroform-Methanol Extract of the Leaves of Persea americana

    PubMed Central

    Christian E, Odo; Okwesili FC, Nwodo; Parker E, Joshua; Okechukwu PC, Ugwu

    2014-01-01

    Persea americana is a plant used by traditional medicine practitioners to treat ailments including diarrhoea and diabetes mellitus in Nigeria. Hence, the chloroform and the methanol fractions of the chloroform-methanol extract of the leaves of P. americana were evaluated for their acute toxicity as well as anti-diarrhoeal effects in Wistar rats to substantiate this claim. The chloroform and methanol fractions [at graded doses of 100 and 200 mg/Kg body weight (b.w) of each] were studied for their anti-diarrhoeal effects in terms of the reductions in the wetness of faeces and the frequency of defaecation of castor oil-induced diarrhoea. To understand the mechanism of their anti-diarrhoeal effects, their actions were further evaluated on castor oil-induced enteropooling (intestinal fluid accumulation). The median lethal dose (LD50) of the methanol fraction was found to be less than 5000 mg/Kg b.w. At the two doses, the chloroform and the methanol fractions showed dose-dependent significant (p < 0.05) reductions in the wetness of faeces and the frequency of defaecation with the 200 mg/Kg b.w of the chloroform fraction being the most effective. Results of the fractions were comparable with those of the standard anti-diarrhoeal drug, hyoscine butylbromide (3 mg/Kg b.w). Both fractions produced remarkable (p < 0.05) dose-related inhibition of castor oil-induced enteropooling as shown by the significant (p < 0.05) decreases in the weight and volume of the intestinal contents. Experimental findings show that the chloroform-methanol extract of the leaves of P. americana possesses significant anti-diarrhoeal effect and may be a potent source of anti-diarrhoeal drug(s) in future. PMID:25237361

  14. Acute Toxicity Investigation and Anti-diarrhoeal Effect of the Chloroform-Methanol Extract of the Leaves of Persea americana.

    PubMed

    Christian E, Odo; Okwesili Fc, Nwodo; Parker E, Joshua; Okechukwu Pc, Ugwu

    2014-01-01

    Persea americana is a plant used by traditional medicine practitioners to treat ailments including diarrhoea and diabetes mellitus in Nigeria. Hence, the chloroform and the methanol fractions of the chloroform-methanol extract of the leaves of P. americana were evaluated for their acute toxicity as well as anti-diarrhoeal effects in Wistar rats to substantiate this claim. The chloroform and methanol fractions [at graded doses of 100 and 200 mg/Kg body weight (b.w) of each] were studied for their anti-diarrhoeal effects in terms of the reductions in the wetness of faeces and the frequency of defaecation of castor oil-induced diarrhoea. To understand the mechanism of their anti-diarrhoeal effects, their actions were further evaluated on castor oil-induced enteropooling (intestinal fluid accumulation). The median lethal dose (LD50) of the methanol fraction was found to be less than 5000 mg/Kg b.w. At the two doses, the chloroform and the methanol fractions showed dose-dependent significant (p < 0.05) reductions in the wetness of faeces and the frequency of defaecation with the 200 mg/Kg b.w of the chloroform fraction being the most effective. Results of the fractions were comparable with those of the standard anti-diarrhoeal drug, hyoscine butylbromide (3 mg/Kg b.w). Both fractions produced remarkable (p < 0.05) dose-related inhibition of castor oil-induced enteropooling as shown by the significant (p < 0.05) decreases in the weight and volume of the intestinal contents. Experimental findings show that the chloroform-methanol extract of the leaves of P. americana possesses significant anti-diarrhoeal effect and may be a potent source of anti-diarrhoeal drug(s) in future. PMID:25237361

  15. Optimization of ethyl ester production assisted by ultrasonic irradiation.

    PubMed

    Noipin, K; Kumar, S

    2015-01-01

    This study presents the optimization of the continuous flow potassium hydroxide-catalyzed synthesis of ethyl ester from palm oil with ultrasonic assistance. The process was optimized by application of factorial design and response surface methodology. The independent variables considered were ethanol to oil molar ratio, catalyst concentration, reaction temperature and ultrasonic amplitude; and the response was ethyl ester yield. The results show that ethanol to oil molar ratio, catalyst concentration, and ultrasonic amplitude have positive effect on ethyl ester yield, whereas reaction temperature has negative influence on ethyl ester yield. Second-order models were developed to predict the responses analyzed as a function of these three variables, and the developed models predicts the results in the experimental ranges studied adequately. This study shows that ultrasonic irradiation improved the ethyl ester production process to achieve ethyl ester yields above 92%. PMID:25116594

  16. Rates of the reactions of 1, 1, 1-trichloroethane /methyl chloroform/ and 1, 1, 2-trichloroethane with OH. [in atmosphere

    NASA Technical Reports Server (NTRS)

    Jeong, K.-M.; Kaufman, F.

    1979-01-01

    Highly purified samples of the two chlorocarbons, trichloroethane and methyl chloroform, were reacted with OH over the temperature range of 278 to 460 K in a discharge-flow system with resonance flourescence detection of OH. Attention is given to the data obtained at various temperature levels and to the graph of Arrhenius' diagram. It is determined that the methyl chloroform reaction was slower and its temperature dependence somewhat steeper than the earlier measurements had indicated, probably due to the presence of faster reacting olefinic impurities in prior studies. Implications for stratospheric ozone reductions by C10-sub-x catalysis and for tropospheric OH-budget are briefly discussed.

  17. Spectral and electroluminescent properties of coordination compounds of terbium (III) with ibuprofen (in solid form, chloroform solutions, and polyvinylcarbazole films)

    NASA Astrophysics Data System (ADS)

    Samsonova, L. G.; Kopylova, T. N.; Degtyarenko, K. M.; Ponarin, N. V.; Meshkova, S. B.; Zheltvai, I. I.

    2015-08-01

    Spectral properties of terbium (III) complexes with composition of TbL3DL, where L is an anion of d,l-2-(4-isobutylphenyl)propanoic acid (ibuprofen) and DL is 2,2'-dipyridyl (Dipy), 1,10-phenanthroline (Phen), or triphenylphosphine oxide (TPPO), have been studied in a solid form, chloroform solutions, and polyvinylcarbazole (PVC) films. It has been demonstrated that, in PVC films, occupation of the emitting level of terbium (III) involves the participation of polymer. The emission decay lifetimes of terbium in the chloroform solutions and PVC films have been measured. The possibility of the appearance of electroluminescence of complexes in PVC films has been studied.

  18. Relative rate constants for the reactions of OH with methane and methyl chloroform

    NASA Technical Reports Server (NTRS)

    Demore, W. B.

    1992-01-01

    Atmospheric lifetimes of methane and methyl chloroform are largely determined by the rates of their reactions with hydroxyl radical. The relative lifetimes for this loss path are inversely proportional to the ratio of the corresponding rate coefficients. The relative rate constants were measured in a slow-flow, temperature-controlled photochemical reactor, and were based on rates of disappearance of the parent compounds as measured by FTIR spectroscopy. The temperature range was 277-356 K. Hydroxyl radicals were generated by 254 nm photolysis of O3 in the presence of water vapor. The preferred Arrhenius expression for the results is k(CH3CCl3)/k(CH4) = 0.62 exp (291/T), corresponding to a value of 1.65 at 298 K and 1.77 at 277 K. The respective uncertainties are 5 and 7 percent.

  19. Carbon Tetrachloride and Chloroform Attenuation Parameter Studies: Heterogeneous Hydrolytic Reactions -- Status Report

    SciTech Connect

    Amonette, James E.; Qafoku, Odeta; Wietsma, Thomas W.; Jeffers, Peter M.; Russell, Colleen K.; Truex, Michael J.

    2009-09-18

    This report documents a project initiated in FY 2006 to help address uncertainties related to the rates of hydrolysis in groundwater for carbon tetrachloride (CT) and chloroform (CF). The study sought also to explore the possible effects of contact with minerals and sediment (i.e., heterogeneous hydrolysis) on these rates. It was funded by the U.S. Department of Energy (DOE) through the Office of Environmental Management Columbia River Protection Supplemental Technologies (CRPST) project and complements work initiated by the Hanford Groundwater Project in FY 2006 that focused primarily on CT in homogenous solution. Work was performed by staff at the Pacific Northwest National Laboratory (PNNL) and the State University of New York at Cortland (SUNY-Cortland).

  20. Abiotic Degradation Rates for Carbon Tetrachloride and Chloroform: Progress in FY2009

    SciTech Connect

    Amonette, James E.; Jeffers, Peter M.; Qafoku, Odeta; Russell, Colleen K.; Wietsma, Thomas W.; Truex, Michael J.

    2010-03-31

    This report documents the progress made through FY 2009 on a project initiated in FY 2006 to help address uncertainties related to the rates of hydrolysis in groundwater for carbon tetrachloride (CT) and chloroform (CF). The study seeks also to explore the possible effects of contact with minerals and sediment (i.e., heterogeneous hydrolysis) on these rates. In previous years the work was funded as two separate projects by various sponsors, all of whom received their funding from the U.S. Department of Energy (DOE). In FY2009, the projects were combined and funded by CH2MHill Plateau Remediation Corporation (CHPRC). Work in FY2009 was performed by staff at the Pacific Northwest National Laboratory (PNNL). Staff from the State University of New York at Cortland (SUNY–Cortland) contributed in previous years.

  1. Nanoaggregation of p3ht in chloroform-anisole solution: relationship between morphology and electrical properties

    NASA Astrophysics Data System (ADS)

    Bielecka, U.; Janus, K.; Bartkowiak, W.

    2014-10-01

    Recent studies of poly(3-hexylthiophene) solutions demonstrate that "sample history" (solution preparation, storage conditions) affects the aggregation process(es) and, consequently, electrical properties. In this paper, we demonstrate the evolution of UV-Vis spectra and the formation of additional red-shifted peaks which visualize the aggregation of p3ht chains. We report comparative study of p3ht based organic field effect transistors fabricated by spin coating using fresh and aged (for 6 months) chloroform solutions with anisole addition. Three order of magnitude improvement in the oFET charge carrier mobility is exhibited. These results provide new insight into p3ht crystallization process(es) and nanofiber-based oFETs.

  2. Antinociceptive Activity of the Chloroform Fraction of Dioclea virgata (Rich.) Amshoff (Fabaceae) in Mice

    PubMed Central

    Mota, Vanine Gomes; de Carvalho, Fabíola Lélis; de Morais, Liana Clébia Soares Lima; Bhattacharyya, Jnanabrata; de Almeida, Reinaldo Nóbrega; de Alencar, Jacicarlos Lima

    2011-01-01

    Acute treatment with the chloroform fraction of Dioclea virgata (Rich.) Amshoff (CFDv) in mice produced decreased ambulation and sedation in the behavioral pharmacological screening. Doses of 125 and 250 mg/kg CFDv decreased latency of sleep onset in the test of sleeping time potentiation. In the open field, animals treated with CFDv reduced ambulation and rearing (250 mg/kg), as well as defecation (125; 250 mg/kg). Regarding the antinociceptive activity, CFDv (125, 250, 500 mg/kg) increased latency to first writhing and decreased the number of writhings induced by acetic acid. In the formalin test, CFDv (250 mg/kg) decreased paw licking time in the first and second phases indicating antinociceptive activity that can be mediated both peripherally and at the central level. CFDv did not affect motor coordination until 120 minutes after treatment. CFDv shows psychopharmacological effects suggestive of CNS-depressant drugs with promising antinociceptive activity. PMID:21776190

  3. [Ether and chloroform narcosis in the pages of Zagreb newspapers from 1847 to 1849].

    PubMed

    Belicza, B

    2000-01-01

    Overviews of the development of anesthesiology in Croatia always emphasize that the first report on the employment of ether anesthesia was published on March 13, 1847, in the Zadar newspaper Gazzeta di Zara. In the world as well, daily newspapers played an important part in spreading the news about the discovery and first use of ether anesthesia. This fact stimulated us to do a systematic search through Zagreb press of that time. Agramer Zeitung (Zagrebacke novine), with its supplement Luna--Beiblatt zur Agramer politischen Zeitung, then Narodne novine and Sudslavische Zeitung (Slavenski jug), were examined for the period from 1846 to the beginning of 1849. Research was directed to give the following answers: when the first writings about discovery and surgery in ether and chloroform anesthesia appeared, which primary and secondary sources of information were used; who wrote them; what kind of attitudes and opinions were promoted, and whose; and finally, did Zagreb newspapers communicate or record the news about first employment of ether and chloroform anesthesia in surgery in Croatia. Research results reveal that Zagreb press had an important role in informing Croatian public about breakthroughs and first experiences in the use of ether and chloroform anesthesia in Europe, and that it contributed to their popularization and employment in our settings. From January 26, 1847, Zagreb papers began publishing first articles about surgeries in ether anesthesia, referring to successes achieved in England and Scotland, and later in Vienna, Berlin, Prague and other big European towns. However, there were no reviews on first successes in America. Sources of information were mainly foreign daily papers, mostly Austrian, and much less often European professional medical journals. Zagreb papers did not report on first surgeries performed in Zadar, Dubrovnik and Split during 1847. The only news from the country referred to the procedure performed in August 1847 in Sisak. This

  4. Phytochemical analysis and antibacterial evaluation of the ethyl acetate extract of the stem bark of Bridelia micrantha

    PubMed Central

    Adefuye, Anthonio O.; Ndip, Roland N.

    2013-01-01

    Background Plant cells fundamentally are chemical factories containing a rich supply of therapeutically useful phytocompounds that have the potential of being developed into potent antimicrobial agents. Aim of the Study: To investigate the antibacterial activity of fractionated extracts of the ethyl acetate extract of the stem bark of Bridelia micrantha (Hochst., Baill., Euphorbiaceae). Materials and Methods: Thin-layer chromatography and column chromatography were used to purify the extracts and antimicrobial activity performed on reference and clinical strains of Staphylococcus aureus, Shigella sonnei, Salmonella Typhimurium, and Helicobacter pylori using direct and indirect bioautographic methods respectively. Furthermore, the eluted compound fractions were then assayed for minimum inhibitory concentration (MIC50) using the 96-well micro dilution technique. Results: Better separation of phytocompounds was obtained from the non-polar Benzene/Ethanol/Ammonia (BEA) and intermediate-polar Chloroform/Ethyl acetate/Formic acid (CEF) eluents compared to the polar Ethanol/Methanol/Water (EMW). Bioautography revealed the presence of three bioactive compounds (Rf values; 0.12, 0.20, and 0.42) on the BEA plates, designated fractions 3, 7, and 8 with MIC50 values; 0.0048mg/mL to 1.25mg/mL (fraction 3), 0.0024mg/mL to 5 mg/mL (fraction 7), and 0.0024mg/mL to 2.5mg/mL (fraction 8). Conclusion: Our findings demonstrate that ethyl acetate extract of the stem-bark of B. micrantha possess potent bioactive phytocompounds that may be developed into new antimicrobials. PMID:23661993

  5. CTAB/water/chloroform reverse micelles: a closed or open association model?

    PubMed

    Klíčová, L'ubica; Sebej, Peter; Štacko, Peter; Filippov, Sergey K; Bogomolova, Anna; Padilla, Marc; Klán, Petr

    2012-10-30

    The micellization of cetyltrimethylammonium bromide (CTAB) in chloroform in the presence of water was examined. Three scenarios of the reverse micelle formation, the closed, open and Eicke's association models, were considered in the interpretation of the experimental data. The growth of the aggregates was observed through the changes of NMR signals of associated water, probing the microenvironment of the premicellar aggregates and the interior of reverse micelles. This technique if combined with isothermal titration calorimetry (ITC) revealed that hydrated surfactant premicellar aggregates are already present at ∼6 mM CTAB. NMR, ITC and conductometry were used to determine the critical micelle concentration (cmc) to be ∼40 mM CTAB. It is suggested that the variation of the cmc values reflects the fact that the NMR analysis indicated the beginning of the reverse micelle formation, whereas conductometry and ITC measurements provided the upper limit and an average value of a so-called apparent cmc, respectively. The cmc values were found to be unaffected by the water content. The presence of reverse micelles, the existence of multiple equilibria, and high polydispersity of the samples were evidenced by DOSY NMR spectroscopy. As a result, we validated Eicke's association model, according to which cyclic inverse micelles are formed by a structural reorganization of linear associates within a narrow concentration range, called the apparent cmc. New experimental results have also been gained for micellization of cetyltrimethylammonium chloride (CTAC) in chloroform in the presence of water; a similar mechanism of reverse micelle formation has been suggested. PMID:23072317

  6. Characterization of Methylocystis strain JTA1 isolated from aged refuse and its tolerance to chloroform.

    PubMed

    Zhao, Tiantao; Zhang, Lijie; Zhang, Yunru; Xing, Zhilin; Peng, Xuya

    2013-04-01

    To accelerate the efficiency of methane biodegradation in landfills, a Gram-negative, rod-shaped, non-motile, non-spore-forming bacterium, JTA1, which can utilize methane as well as acetate, was isolated from the Laogang MSW landfills, Shanghai, China. Strain JTA1 was a member of genus Methylocystis on the basis of 16S rRNA and pmoA gene sequence similarity. The maximum specific cell growth rates (micro(max) = 0.042 hr(-1), R2 = 0.995) was derived through Boltzmann simulation, and the apparent half-saturation constants (K(m(app)) = 7.08 mmol/L, R2 = 0.982) was calculated according to Michaelis-Menton hyperbolic model, indicating that Methylocystis strain JTA1 had higher-affinity potential for methane oxidation than other reported methanotrophs. By way of adding the strain JTA1 culture, the methane consumption of aged refuse reached 115 mL, almost two times of control experiment. In addition, high tolerance of Methylocystis strain JTA1 to chloroform could facilitate the methane oxidation of aged refuse bio-covers. At the chloroform concentration of 50 mg/L, the methane-oxidation rate of bio-cover reached 0.114 mL/(day x g), much higher than the highest rate, 0.0135 mL/(day x g), of reported bio-covers. In conclusion, strain JTA1 opens up a new possibility for environmental biotechnology, such as soil or landfills bioremediation and wastewater decontamination. PMID:23923786

  7. Testing for ethanol markers in hair: discrepancies after simultaneous quantification of ethyl glucuronide and fatty acid ethyl esters.

    PubMed

    Kintz, P; Nicholson, D

    2014-10-01

    The hair of 97 cases were analysed for ethyl glucuronide (EtG) and fatty acid ethyl esters (FAEE, including ethyl myristate, ethyl palmitate, ethyl oleate and ethyl stearate) according to the Society of Hair Testing guidelines to examine the role of both tests in documenting chronic excessive alcohol drinking, particularly when the results are in contradiction. 27 (27.8%) results were EtG negative and FAEE positive, when applying the SoHT cut-offs, probably due to the use of alcohol-containing hair products. Four cases (4.1%) were EtG positive and FAEE negative that were attributed to the use of herbal lotions containing EtG. PMID:24794020

  8. Olanzapine-induced hyperglycemic ketoacidosis and corresponding acetone concentrations post-mortem: a forensic interpretation.

    PubMed

    House, Chris J

    2007-08-24

    Olanzapine has been shown to cause or have a contributory role in the development of hyperglycemia and diabetes mellitus. Without careful monitoring for the development of these conditions and control of the resulting adverse effects, patients receiving olanzapine may be at risk of developing fatal ketoacidosis. A review of post-mortem toxicological reports has revealed an increase in the incidence of post-mortem findings of acetone in decedents who were taking olanzapine over the past decade. A review of the current literature and a comprehensive review of case histories and toxicological findings were conducted at the Centre of Forensic Sciences (Toronto, Ontario). Olanzapine concentrations ranging from <62.5 to 858 ng/mL and acetone concentrations as high as 95 mg/dL were detected concurrently. Due to the unstable nature of olanzapine, in several instances quantitation was not possible despite elevated responses during qualitative screening procedures. Five cases suggesting olanzapine-induced ketoacidosis were identified based on the case history and toxicological findings. These data have been compiled and examined with respect to acetone concentrations following olanzapine use and the forensic relevance of post-mortem olanzapine and acetone concentrations are discussed. PMID:17084052

  9. Chemical-specific adjustment factors for intraspecies variability of acetone toxicokinetics using a probabilistic approach.

    PubMed

    Mörk, Anna-Karin; Johanson, Gunnar

    2010-07-01

    Human health risk assessment has begun to depart from the traditional methods by replacement of the default assessment factors by more reasonable, data-driven, so-called chemical-specific adjustment factors (CSAFs). This study illustrates a scheme for deriving CSAFs in the general and occupationally exposed populations by quantifying the intraspecies toxicokinetic variability in surrogate dose using probabilistic methods. Acetone was used as a model substance. The CSAFs were derived by Monte Carlo simulation, combining a physiologically based pharmacokinetic model for acetone, probability distributions of the model parameters from a Bayesian analysis of male volunteer experimental data, and published distributions of physiological and anatomical parameters for females and children. The simulations covered how factors such as age, gender, endogenous acetone production, and fluctuations in workplace air concentration and workload influence peak and average acetone levels in blood, used as surrogate doses. According to the simulations, CSAFs of 2.1, 2.9, and 3.8 are sufficient to cover the differences in surrogate dose at the upper 90th, 95th, and 97.5th percentile, respectively, of the general population. However, higher factors were needed to cover the same percentiles of children. The corresponding CSAFs for the occupationally exposed population were 1.6, 1.8, and 1.9. The methodology presented herein allows for derivation of CSAFs not only for populations as a whole but also for subpopulations of interest. Moreover, various types of experimental data can readily be incorporated in the model. PMID:20400482

  10. Extraction of certain elements from aqueous methanol, ethanol and acetone by tridodecylamine and tributyl phosphate.

    PubMed

    Alian, A; Sanad, W; Khalifa, H

    1968-02-01

    The extraction of silver, mercury, selenium, zinc, cobalt and iron with tridodecylamine (TDA) and tributyl phosphate (TBP) from hydrochloric acid solutions in aqueous methanol, ethanol and acetone is reported. The presence of these additives increases extraction for some elements and decreases it for others. The effect is generally greater with TDA than with TBP. PMID:18960287

  11. A simple procedure for preparing chitin oligomers through acetone precipitation after hydrolysis in concentrated hydrochloric acid.

    PubMed

    Kazami, Nao; Sakaguchi, Masayoshi; Mizutani, Daisuke; Masuda, Tatsuhiko; Wakita, Satoshi; Oyama, Fumitaka; Kawakita, Masao; Sugahara, Yasusato

    2015-11-01

    Chitin oligomers are of interest because of their numerous biologically relevant properties. To prepare chitin oligomers containing 4-6 GlcNAc units [(GlcNAc)4-6], α- and β-chitin were hydrolyzed with concentrated hydrochloric acid at 40 °C. The reactant was mixed with acetone to recover the acetone-insoluble material, and (GlcNAc)4-6 was efficiently recovered after subsequent water extraction. Composition analysis using gel permeation chromatography and MALDI-TOF mass spectrometry indicated that (GlcNAc)4-6 could be isolated from the acetone-insoluble material with recoveries of approximately 17% and 21% from the starting α-chitin and β-chitin, respectively. The acetone precipitation method is highly useful for recovering chitin oligomers from the acid hydrolysate of chitin. The changes in the molecular size and higher-order structure of chitin during the course of hydrolysis were also analyzed, and a model that explains the process of oligomer accumulation is proposed. PMID:26256353

  12. Carbon and proton Overhauser DNP from MD simulations and ab initio calculations: TEMPOL in acetone.

    PubMed

    Küçük, Sami Emre; Biktagirov, Timur; Sezer, Deniz

    2015-10-14

    A computational analysis of the Overhauser effect is reported for the proton, methyl carbon, and carbonyl carbon nuclei of liquid acetone doped with the nitroxide radical TEMPOL. A practical methodology for calculating the dynamic nuclear polarization (DNP) coupling factors by accounting for both dipole-dipole and Fermi-contact interactions is presented. The contribution to the dipolar spectral density function of nuclear spins that are not too far from TEMPOL is computed through classical molecular dynamics (MD) simulations, whereas the contribution of distant spins is included analytically. Fermi contacts are obtained by subjecting a few molecules from every MD snapshot to ab initio quantum mechanical calculations. Scalar interaction is found to be an essential part of the (13)C Overhauser DNP. While mostly detrimental to the carbonyl carbon of acetone it is predicted to result in large enhancements of the methyl carbon signal at magnetic fields of 9 T and beyond. In contrast, scalar coupling is shown to be negligible for the protons of acetone. The additional influence of proton polarization on the carbon DNP (three-spin effect) is also analyzed computationally. Its effect, however, is concluded to be practically insignificant for liquid acetone. PMID:26343351

  13. Photooxidation of Isopropanol and Acetone Using TiO(sub 2) Suspension and UV Light

    SciTech Connect

    El-Morsi, Taha; Nanny, Mark A.

    2004-03-31

    Small polar organic compounds such as alcohols, ketones and aldehydes are highly soluble and do not adsorb strongly to the TiO2 surface and, therefore, may be fairly resistant to photocatalytic degradation. Photodegradation of an aqueous solution of isopropanol and its resulting photodegradation product acetone was investigated as a function of TiO2 substrate concentrations and solution ionic strength and pH. In the presence of 2g/L TiO2, isopropanol completely disappeared within 3 hrs, resulting in the nearly complete transformation into acetone. Subsequent photodegradation of acetone occurred at a much slower rate and resulted in complete mineralization. Increasing the pH slightly decreased the photodegradation rate. Conversely, the degradation rate was enhanced slightly by increasing the ionic strength. The presence of tetranitromethane decreased the isopropanol degradation significantly. This result, combined with the minimal degree of adsorption of isopropanol and acetone onto the surface of the photocatalyst, suggests that the photodegradation pathway occurs via free OH radicals in bulk solution rather than on the catalyst surface.

  14. Assessment of in situ butanol recovery by vacuum during acetone butanol ethanol (ABE) fermentation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Butanol fermentation is product limiting due to butanol toxicity to microbial cells. Butanol (boiling point: 118 deg C) boils at a greater temperature than water (boiling point: 100 deg C) and application of vacuum technology to integrated acetone-butanol-ethanol (ABE) fermentation and recovery may ...

  15. Comparative study of free and immobilized lipase from Bacillus aerius and its application in synthesis of ethyl ferulate.

    PubMed

    Saun, Nitin Kumar; Narwal, Sunil Kumar; Dogra, Priyanka; Chauhan, Ghanshyam Singh; Gupta, Reena

    2014-01-01

    In the present study, a purified lipase from Bacillus aerius immobilized on celite matrix was used for synthesis of ethyl ferulate. The celite-bound lipase exposed to glutaraldehyde showed 90.02% binding efficiency. It took two hours to bind maximally onto the support. The pH and temperature optima of the immobilized lipase were same as those of free enzyme i.e 9.5 and 55°C. Among different substrates both free and immobilized lipase showed maximum affinity towards p-nitrophenyl palmitate (p-NPP). The lipase activity was found to be stimulated in the presence of Mg(2+) in case of free enzyme while Zn(2+) and Fe(3+) showed stimulatory effect on immobilized lipase whereas salt ions as well as chelating agents inhibited activity of both free and immobilized lipase. Maximum enzyme activity was observed in n-hexane as organic solvent followed by n-heptane for both free and immobilized lipase, however CCl4, acetone and benzene inhibited the enzyme activity. Moreover, all the selected detergents (SDS, Triton X-100, Tween 80 and Tween 20) had an inhibitory effect on both free and immobilized enzyme activity. The celite bound lipase (1.5%) efficiently performed maximum esterification (2.51 moles/l) of ethanol and ferulic acid (100 mM each, at a molar ratio of 1:3) when incubated at 55°C for 48 h resulting in the formation of ester ethyl ferulate. PMID:25099909

  16. Ethyl-p-aminobenzoate (Benzocaine): efficacy as an anesthetic for five species of freshwater fish

    USGS Publications Warehouse

    Dawson, V.K.; Gilderhus, P.A.

    1979-01-01

    Ethyl-p-aminobenzoate (benzocaine) was tested for its efficacy as an anesthetic for rainbow trout (Salmo gairdnerii, brown trout (Salmo truttas, northern pike (Esox lucius). carp (Cyprinus carpio), and largemouth bass (Mieropterus salmoidesi. Since benzocaine is not water soluble, it was applied with acetone as a carrier. Concentrations of 100 to 200 mg!l were required for large adult northern pike, compared with 50 to 100 mg/l for small fish. Rates of sedation and recovery were slower in cold water than in warm water. Water hardness had little influence on the activity of benzocaine. Fish were anesthetized faster and recovered more slowly in acid than in alkaline water. Benzocaine produced deep anesthesia, but concentrations that rendered the fish handleable within 5 min were generally not safe for exposures longer than 15 min. Concentrations of benzocaine efficacious for fish were not acutely toxic to eggs of coho salmon (Oncorhynchus kisutch), chinook salmon (Oncorhynchus tshauiytschas, rainbow trout, brown trout, or lake trout (Salvelinus namaycush). Benzocaine is not registered for fishery use and is neither more effective nor safer than the registered anesthetic, tricaine methanesulfonate (MS-222l.

  17. An Acetone Microsensor with a Ring Oscillator Circuit Fabricated Using the Commercial 0.18 μm CMOS Process

    PubMed Central

    Yang, Ming-Zhi; Dai, Ching-Liang; Shih, Po-Jen

    2014-01-01

    This study investigates the fabrication and characterization of an acetone microsensor with a ring oscillator circuit using the commercial 0.18 μm complementary metal oxide semiconductor (CMOS) process. The acetone microsensor contains a sensitive material, interdigitated electrodes and a polysilicon heater. The sensitive material is α-Fe2O3 synthesized by the hydrothermal method. The sensor requires a post-process to remove the sacrificial oxide layer between the interdigitated electrodes and to coat the α-Fe2O3 on the electrodes. When the sensitive material adsorbs acetone vapor, the sensor produces a change in capacitance. The ring oscillator circuit converts the capacitance of the sensor into the oscillation frequency output. The experimental results show that the output frequency of the acetone sensor changes from 128 to 100 MHz as the acetone concentration increases 1 to 70 ppm. PMID:25036331

  18. BaFe12O19 powder with high magnetization prepared by acetone-aided coprecipitation

    NASA Astrophysics Data System (ADS)

    Yu, Hsuan-Fu

    2013-09-01

    BaFe12O19 particles with high magnetization were produced using an acetone-aided coprecipitation process. An aqueous solution of iron and barium nitrates, in an Fe3+/Ba2+ molar ratio of 12, was added in a stirred precipitation liquid medium composed of H2O, CH3(CO)CH3 and NH4OH. After reacting metallic ions with ammonia, the precipitates were formed, centrifugally filtered, freeze dried and calcined. Effects of amount of the acetone in the precipitation liquid medium on the formation of crystalline BaFe12O19 were investigated. The presence of acetone in the precipitation liquid medium can greatly promote formation of the crystalline BaFe12O19 at temperature as low as 650 °C and can enhance magnetization of the derived particles. On the other hand, raising the calcination temperature can effectively accelerate development of crystallite morphology and magnetic characters of the barium hexaferrites. While the barium hexaferrite powder obtained without acetone additions and calcined at 1000 °C had magnetization (measured at 50 kOe; M(50 kOe)) of 63.5 emu/g, remanence magnetization (Mr) of 31.3 emu/g and coercivity (Hc) of 4.7 kOe, the single magnetic domain size BaFe12O19 powder with M(50 kOe) of 70.6 emu/g, Mr of 34.4 emu/g and Hc of 3.7 kOe was produced at 1000 °C, using a precipitation liquid medium of 64 vol% acetone.

  19. Kinetics of hydroperoxy radical reactions with acetone/HO2 adduct and with acetonylperoxy radical

    NASA Astrophysics Data System (ADS)

    Grieman, F. J.; VanDerGeest, K.; Newenhouse, E.; Watkins, K.; Noell, A. C.; Hui, A.; Sander, S. P.; Okumura, M.

    2013-12-01

    Reactions of hydroperoxy radical, HO2, with acetone and with acetonylperoxy radical, CH3C(O)CH2OO, may play an important role in the oxidation chemistry of the troposphere. Using a temperature-controlled slow-flow tube cell and laser flash photolysis of Cl2 to produce HO2 and CH3C(O)CH2OO from methanol and acetone, respectively, we studied the chemical kinetics involved over the temperature range of 215 to 298 K at 100 Torr. Rates of chemical reactions were determined by monitoring the HO2 concentration as a function of time by near-IR diode laser wavelength modulation spectroscopy. (See Fig.1.) The primary reactions are rapid (<100 μsec) reactions to form the adducts HO2-CH3OH and HO2-CH3C(O)CH3 followed by HO2 reactions with itself, the adducts (chaperone mechanisms), and acetonylperoxy radical. The equilibrium constants for adduct formation were determined in previous work.1,2 In this work, rate coefficients were determined for the acetone chaperone mechanism over the entire temperature range. (E.g., see Fig. 2.) The rate coefficients and energies obtained are very similar to those found for the methanol case.1 Rate coefficients for the CH3C(O)CH2OO/HO2 reaction were also determined over a smaller temperature range, extending the measured value beyond room temperature, and yielding an activation energy. 1. Christensen et al. J. Phys. Chem. A 2006, 110, 6948-6959. 2. Grieman et al. J. Phys. Chem. A 2011, 115, 10527-10538. Fig.1. HO2 decay for HO2/Acetone chemistry at T = 298 K. Fig.2. Determining rate coefficient (k") for HO2/acetone chaperone effect at T = 222.5 K.

  20. Profiling and relative quantification of phosphatidylethanolamine based on acetone stable isotope derivatization.

    PubMed

    Wang, Xiang; Wei, Fang; Xu, Ji-qu; Lv, Xin; Dong, Xu-yan; Han, Xianlin; Quek, Siew-young; Huang, Feng-hong; Chen, Hong

    2016-01-01

    Phosphatidylethanolamine (PE) is considered to be one of the pivotal lipids for normal cellular function as well as disease initiation and progression. In this study, a simple, efficient, reliable, and inexpensive method for the qualitative analysis and relative quantification of PE, based on acetone stable isotope derivatization combined with double neutral loss scan-shotgun electrospray ionization tandem-quadrupole mass spectrometry analysis (ASID-DNLS-Shotgun ESI-MS/MS), was developed. The ASID method led to alkylation of the primary amino groups of PE with an isopropyl moiety. The use of acetone (d0-acetone) and deuterium-labeled acetone (d6-acetone) introduced a 6 Da mass shift that was ideally suited for relative quantitative analysis, and enhanced sensitivity for mass analysis. The DNLS model was introduced to simultaneously analyze the differential derivatized PEs by shotgun ESI-MS/MS with high selectivity and accuracy. The reaction specificity, labeling efficiency, and linearity of the ASID method were thoroughly evaluated in this study. Its excellent applicability was validated by qualitative and relative quantitative analysis of PE species presented in liver samples from rats fed different diets. Using the ASID-DNLS-Shotgun ESI-MS/MS method, 45 PE species from rat livers have been identified and quantified in an efficient manner. The level of total PEs tended to decrease in the livers of rats on high fat diets compared with controls. The levels of PE 32:1, 34:3, 34:2, 36:3, 36:2, 42:10, plasmalogen PE 36:1 and lyso PE 22:6 were significantly reduced, while levels of PE 36:1 and lyso PE 16:0 increased. PMID:26703264

  1. EFFECTS OF CHLOROFORM IN THE DRINKING WATER OF RATS AND MICE: NINETY-DAY SUBACUTE TOXICITY STUDY

    EPA Science Inventory

    This research was initiated to provide toxicologic and range finding data sufficient for setting dose levels for the chronic phase testing of chloroform in drinking water of male Osborne-Mendel rats and female B6C3F1 mice. A 90-day subchronic study was designed to investigate the...

  2. Factors associated with sources, transport, and fate of chloroform and three other trihalomethanes in untreated groundwater used for drinking water

    USGS Publications Warehouse

    Carter, Janet M.; Moran, Michael J.; Zogorski, John S.; Price, Curtis V.

    2012-01-01

    Multiple lines of evidence for indicating factors associated with the sources, transport, and fate of chloroform and three other trihalomethanes (THMs) in untreated groundwater were revealed by evaluating low-level analytical results and logistic regression results for THMs. Samples of untreated groundwater from wells used for drinking water were collected from 1996-2007 from 2492 wells across the United States and analyzed for chloroform, bromodichloromethane, dibromochloromethane, and bromoform by a low-level analytical method implemented in April 1996. Using an assessment level of 0.02 μg/L, chloroform was detected in 36.5% of public-well samples and 17.6% of domestic-well samples, with most concentrations less than 1 μg/L. Brominated THMs occurred less frequently than chloroform but more frequently in public-well samples than domestic-well samples. For both public and domestic wells, THMs occurred most frequently in urban areas. Logistic regression analyses showed that the occurrence of THMs was related to nonpoint sources such as urban land use and to point sources like septic systems. The frequent occurrence and concentration distribution pattern of THMs, as well as their frequent co-occurrence with other organic compounds and nitrate, all known to have anthropogenic sources, and the positive associations between THM occurrence and dissolved oxygen and recharge indicate the recycling of water that contains THMs and other anthropogenic contaminants.

  3. Attenuation of nonenzymatic glycation, hyperglycemia, and hyperlipidemia in streptozotocin-induced diabetic rats by chloroform leaf extract of Azadirachta indica

    PubMed Central

    Gutierrez, Rosa Martha Pérez; Gómez, Yolanda Gómez Y.; Guzman, Mónica Damián

    2011-01-01

    Background: The hypoglycemic effects of hexane, chloroform and methanol extracts of leaves of Azadirachta indica (AI) were evaluated by oral administration in streptozotocin-induced severe diabetic rats (SD). Materials and Methods: The effect of chronic oral administration of the extract for 28 days was evaluated in streptozotozin diabetic rats. Lipid peroxidation, glycogen content of liver and skeletal muscles, insulin, superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), oxidized glutathione (GSSG) levels were determined. In addition, advanced glycation end product formation (AGEs) was evaluated. Results: The most active extracts were obtained with chloroform. Chloroform extract from AI shows increased levels of SOD, GSH, GSSG and CAT, hepatic glycogen content, glucose-6-phosphatase and insulin plasma levels, which also decreased the glucokinase (GK), lipid peroxidation and insulin resistance. The chloroform extract exhibited significant inhibitory activity against advanced glycation end product formation with an IC50 average range of 79.1 mg/ml. Conclusion: Azadirachta indica can improve hyperlipidemia and hyperinsulinema in streptozocin-induced diabetic rats and, therefore, AI can be potentially considered to be an antidiabetic-safe agent. PMID:21969798

  4. Chloroform in the hydrologic system--sources, transport, fate, occurrence, and effects on human health and aquatic organisms

    USGS Publications Warehouse

    Ivahnenko, Tamara; Barbash, Jack E.

    2004-01-01

    Chloroform is one of the volatile organic compounds (VOCs) detected most frequently in both ground and surface water. Because it is also one of the four trihalomethanes (THMs) produced in the highest concentrations during the chlorination of drinking water and wastewater, the frequent detection of this compound in ground and surface water of the United States is presumed to be caused primarily by the input of chlorinated water to the hydrologic system. Although anthropogenic sources of the compound are substantial, they are currently estimated to constitute only 10 percent of the total global input to the hydrologic system. Natural sources of the compound include volcanic gases, biomass burning, marine algae, and soil microorganisms. Under most conditions (except in the presence of unusually high bromide concentrations), chloroform is the THM produced in the highest concentrations during chlorination. Furthermore, in most cases where more than one THM is produced from chlorination, the relative concentrations among the different compounds usually decrease with increasing bromination (chloroform > dichlorobromomethane > chlorodibromomethane > bromoform). This phenomenon is presumed to be responsible for the common observation that when more than one THM is detected during investigations of the occurrence of these compounds in the hydrologic system, this same trend is typically observed among their relative concentrations or, for a uniform reporting limit, their relative frequencies of detection. This pattern could provide a valuable means for distinguishing between chlorinated water and other potential sources of chloroform in the environment. Chloroform has been widely detected in national, regional, and local studies of VOCs in ground, surface, source, and drinking waters. Total THM (TTHM) concentrations of the compound, however, were typically less than the Maximum Contaminant Level (MCL) of 80 ?g/L (micrograms per liter) established by the U.S. Environmental

  5. IRIS TOXICOLOGICAL REVIEW OF METHYL ETHYL KETONE (2003 Final)

    EPA Science Inventory

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

  6. 46 CFR 151.50-42 - Ethyl ether.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Ethyl ether. 151.50-42 Section 151.50-42 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES BARGES CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-42 Ethyl ether. (a)(1) Gravity...

  7. EFFECT OF SUBSEQUENT TREATMENT OF CHLOROFORM OF PHENOBARBITAL ON THE INCIDENCE OF LIVER AND LUNG TUMORS INITIATED BY ETHYLNITROSOUREA IN 15 DAY OLD MICE

    EPA Science Inventory

    The effect of subsequent administration of chloroform or phenobarbital on the incidence of ethylnitrosourea (ENU) initiated liver and lung tumors was investigated. Fifteen day old Swiss mice were administered ENU, and at weaning they started to receive either 1800 ppm chloroform ...

  8. USE OF SENSITIVITY ANALYSIS ON A PHYSIOLOGICALLY-BASED PHARMACOKINETIC (PBPK) MODEL FOR CHLOROFORM IN RATS TO DETERMINE AGE-RELATED TOXICITY

    EPA Science Inventory

    USE OF SENSITIVITY ANALYSIS ON A PHYSIOLOGICALLY BASED PHARMACOKINETIC (PBPK) MODEL FOR CHLOROFORM IN RATS TO DETERMINE AGE-RELATED TOXICITY.
    CR Eklund, MV Evans, and JE Simmons. US EPA, ORD, NHEERL, ETD,PKB, Research Triangle Park, NC.

    Chloroform (CHCl3) is a disinfec...

  9. THE FAILURE OF CHLOROFORM ADMINISTERED IN THE DRINKING WATER TO INDUCE RENAL TUBULAR CELL NEOPLASIA IN MALE F344/N RATS

    EPA Science Inventory

    The failure of chloroform administered in drinking water to induce renal tubular cell neoplasia in male F344/N rats

    Chloroform (TCM) has been demonstrated to be a renal carcinogen in the male Osborne-
    Mendel rat when administered either by corn oil gavage or in drin...

  10. The natural chlorine cycle - Formation of the carcinogenic and greenhouse gas compound chloroform in drinking water reservoirs.

    PubMed

    Forczek, Sándor T; Pavlík, Milan; Holík, Josef; Rederer, Luděk; Ferenčík, Martin

    2016-08-01

    Chlorine cycle in natural ecosystems involves formation of low and high molecular weight organic compounds of living organisms, soil organic matter and atmospherically deposited chloride. Chloroform (CHCl3) and adsorbable organohalogens (AOX) are part of the chlorine cycle. We attempted to characterize the dynamical changes in the levels of total organic carbon (TOC), AOX, chlorine and CHCl3 in a drinking water reservoir and in its tributaries, mainly at its spring, and attempt to relate the presence of AOX and CHCl3 with meteorological, chemical or biological factors. Water temperature and pH influence the formation and accumulation of CHCl3 and affect the conditions for biological processes, which are demonstrated by the correlation between CHCl3 and ΣAOX/Cl(-) ratio, and also by CHCl3/ΣAOX, CHCl3/AOXLMW, CHCl3/ΣTOC, CHCl3/TOCLMW and CHCl3/Cl(-) ratios in different microecosystems (e.g. old spruce forest, stagnant acidic water, humid and warm conditions with high biological activity). These processes start with the biotransformation of AOX from TOC, continue via degradation of AOX to smaller molecules and further chlorination, and finish with the formation of small chlorinated molecules, and their subsequent volatilization and mineralization. The determined concentrations of chloroform result from a dynamic equilibrium between its formation and degradation in the water; in the Hamry water reservoir, this results in a total amount of 0.1-0.7 kg chloroform and 5.2-15.4 t chloride. The formation of chloroform is affected by Cl(-) concentration, by concentrations and ratios of biogenic substrates (TOC and AOX), and by the ratios of the substrates and the product (feedback control by chloroform itself). PMID:27231877

  11. A morphogenetic regulatory role for ethyl alcohol in Candida albicans.

    PubMed

    Chauhan, Nitin M; Raut, Jayant S; Karuppayil, S Mohan

    2011-11-01

    Regulation of morphogenesis through the production of chemical signalling molecules such as isoamyl alcohol, 2-phenylethyl alcohol, 1-dodecanol, E-nerolidol and farnesol is reported in Candida albicans. The present study focuses on the effect of ethyl alcohol on C. albicans dimorphism and biofilm development. Ethyl alcohol inhibited germ tube formation induced by the four standard inducers in a concentration-dependent manner. The germ tube inhibitory concentration (4%) did not have any effect on the growth and viability of C. albicans cells. Ethyl alcohol also inhibited the elongation of germ tubes. Four percentage of ethyl alcohol significantly inhibited biofilm development on polystyrene and silicone surfaces. We suggest a potential morphogenetic regulatory role for ethyl alcohol, which may influence dissemination, virulence and establishment of infection. PMID:21605190

  12. Fragmentation dynamics of the ethyl bromide and ethyl iodide cations: a velocity-map imaging study.

    PubMed

    Gardiner, Sara H; Karsili, Tolga N V; Lipciuc, M Laura; Wilman, Edward; Ashfold, Michael N R; Vallance, Claire

    2014-02-01

    The photodissociation dynamics of ethyl bromide and ethyl iodide cations (C2H5Br(+) and C2H5I(+)) have been studied. Ethyl halide cations were formed through vacuum ultraviolet (VUV) photoionization of the respective neutral parent molecules at 118.2 nm, and were photolysed at a number of ultraviolet (UV) photolysis wavelengths, including 355 nm and wavelengths in the range from 236 to 266 nm. Time-of-flight mass spectra and velocity-map images have been acquired for all fragment ions and for ground (Br) and spin-orbit excited (Br*) bromine atom products, allowing multiple fragmentation pathways to be investigated. The experimental studies are complemented by spin-orbit resolved ab initio calculations of cuts through the potential energy surfaces (along the RC-Br/I stretch coordinate) for the ground and first few excited states of the respective cations. Analysis of the velocity-map images indicates that photoexcited C2H5Br(+) cations undergo prompt C-Br bond fission to form predominantly C2H5(+) + Br* products with a near-limiting 'parallel' recoil velocity distribution. The observed C2H3(+) + H2 + Br product channel is thought to arise via unimolecular decay of highly internally excited C2H5(+) products formed following radiationless transfer from the initial excited state populated by photon absorption. Broadly similar behaviour is observed in the case of C2H5I(+), along with an additional energetically accessible C-I bond fission channel to form C2H5 + I(+) products. HX (X = Br, I) elimination from the highly internally excited C2H5X(+) cation is deemed the most probable route to forming the C2H4(+) fragment ions observed from both cations. Finally, both ethyl halide cations also show evidence of a minor C-C bond fission process to form CH2X(+) + CH3 products. PMID:24317740

  13. Mechanistic insight into alkylation of the ethyl acetoacetate anion with different ethyl halides

    NASA Astrophysics Data System (ADS)

    Marković, S.; Đurđević, J.; Vukosavljević, M.; Petrović, Z.

    2013-12-01

    The alkylation reactions of the ambident ethyl acetoacetate anion with C2H5X (X = F, Cl, Br, and I) in the O2, C3, and O4 positions of the anion were investigated at the B3LYP/6-311+G( d,p) level of theory. It was found that the ethylation reaction does not occur in the position O4, as well as with ethyl fluoride in any position of the anion, due to very high activation energies and thermodynamic instability of the hypothetic products. The activation energies for the reactions in the position O2 are lower in comparison to the position C3, but the products of the reactions in the C3 position are more stable than those in the position O4, implying that the C/O products ratio is controlled by both thermodynamic and kinetic factors, leading to the O2-product with the chloride, and C3-product with the iodide as leaving group.

  14. Determination of equilibrium constants for the reaction between acetone and HO2 using infrared kinetic spectroscopy.

    PubMed

    Grieman, Fred J; Noell, Aaron C; Davis-Van Atta, Casey; Okumura, Mitchio; Sander, Stanley P

    2011-09-29

    The reaction between the hydroperoxy radical, HO(2), and acetone may play an important role in acetone removal and the budget of HO(x) radicals in the upper troposphere. We measured the equilibrium constants of this reaction over the temperature range of 215-272 K at an overall pressure of 100 Torr using a flow tube apparatus and laser flash photolysis to produce HO(2). The HO(2) concentration was monitored as a function of time by near-IR diode laser wavelength modulation spectroscopy. The resulting [HO(2)] decay curves in the presence of acetone are characterized by an immediate decrease in initial [HO(2)] followed by subsequent decay. These curves are interpreted as a rapid (<100 μs) equilibrium reaction between acetone and the HO(2) radical that occurs on time scales faster than the time resolution of the apparatus, followed by subsequent reactions. This separation of time scales between the initial equilibrium and ensuing reactions enabled the determination of the equilibrium constant with values ranging from 4.0 × 10(-16) to 7.7 × 10(-18) cm(3) molecule(-1) for T = 215-272 K. Thermodynamic parameters for the reaction determined from a second-law fit of our van't Hoff plot were Δ(r)H°(245) = -35.4 ± 2.0 kJ mol(-1) and Δ(r)S°(245) = -88.2 ± 8.5 J mol(-1) K(-1). Recent ab initio calculations predict that the reaction proceeds through a prereactive hydrogen-bonded molecular complex (HO(2)-acetone) with subsequent isomerization to a hydroxy-peroxy radical, 2-hydroxyisopropylperoxy (2-HIPP). The calculations differ greatly in the energetics of the complex and the peroxy radical, as well as the transition state for isomerization, leading to significant differences in their predictions of the extent of this reaction at tropospheric temperatures. The current results are consistent with equilibrium formation of the hydrogen-bonded molecular complex on a short time scale (100 μs). Formation of the hydrogen-bonded complex will have a negligible impact on the

  15. Effects of acetone on electrooxidation of 2-propanol in alkaline medium on the Pd/Ni-foam electrode

    NASA Astrophysics Data System (ADS)

    Cheng, Yuanhui; Liu, Yao; Cao, Dianxue; Wang, Guiling; Gao, Yinyi

    2011-03-01

    Acetone is the main product of 2-propanol electrooxidation in both acid and alkaline electrolytes; it always co-exists with 2-propanol in the reaction solution due to its liquid nature. Whether acetone will affect the electrooxidation of 2-propanol has not been well documented, which is a key issue that needs to be addressed for the direct 2-propanol fuel cell. In this study, the influence of acetone on the electrooxidation of 2-propanol in alkaline medium is investigated, using state-of-the-art Pd electrode, by cyclic voltammetry and chronoamperometry. The electrode is prepared using a chemical replacement method, by dipping nickel foam into acidified PdCl2 solution, and characterized by scanning electron microscopy. We found that the presence of acetone adversely affects electrooxidation performance of 2-propanol and substantially reduces the oxidation current of 2-propanol on Pd in alkaline medium. The acetone poisoning effect is interpreted by a competitive adsorption mechanism, in which acetone adsorbs onto Pd surface and occupies the active sites for 2-propanol electrooxidation, leading to a significant decrease in the number of these sites for 2-propanol electrooxidation. The results of this study point out that efficient electrocatalysts for 2-propanol electrooxidation in alkaline electrolytes must be non-adsorptive to acetone besides being highly active to 2-propanol oxidation.

  16. 40 CFR 721.6660 - Polymer of alkanepolyol and poly-alkyl-poly-iso-cyan-ato-car-bo-mo-no-cycle, acetone oxime...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-poly-iso-cyan-ato-car-bo-mo-no-cycle, acetone oxime-blocked (generic name). 721.6660 Section 721.6660... Polymer of alkanepolyol and poly-alkyl-poly-iso-cyan-ato-car-bo-mo-no-cycle, acetone oxime-blocked..., acetone oxime-blocked (PMN P-88-1658) is subject to reporting under this section for the significant...

  17. Photooxidation of Acetone on TiO2(110): Conversion to Acetate via Methyl Radical Ejection

    SciTech Connect

    Henderson, Michael A.

    2005-06-23

    It is generally held that radicals form and participate in heterogeneous photocatalytic processes on oxide surfaces, although understanding the mechanistic origins and fates of such species is difficult. In this study, photodesorption and thermal desorption techniques show that acetone is converted into acetate on the surface of TiO(110) in a two step process that involves, first, a thermal reaction between acetone and coadsorbed oxygen to make a surface acetone-oxygen complex, followed second by a photochemical reaction that ejects a methyl radical from the surface and converts the acetone-oxygen complex into acetate. Designation of the photodesorption species to methyl radicals was confirmed using isotopically labeled acetone. The yield of photodesorbed methyl radicals correlates well with the amount depleted of acetone and with the yield of acetate left on the surface, both gauged using post-irradiation temperature programmed desorption (TPD). The thermal reaction between adsorbed acetone and oxygen to form the acetone-oxygen complex exhibits an approximate activation barrier of about 10 kJ/mol. A prerequisite to this reaction is the presence of surface Ti?? sites that enable O? adsorption. Creation of these sites by vacuum reduction of the surface prior to acetone and oxygen co-adsorption results in an initial spike in the photodecomposition rate, but replenishment of these sites by photolytic means (i.e., by trapping excited electrons at the surface) appears to be a slow step a sustained reaction. Evidence in this study for the ejection of organic radicals from the surface during photo-oxidation catalysis on TiO provides support for mechanistic pathways that involve both adsorbed and non-adsorbed species.

  18. The synthesis, structure and properties of N-acetylated derivatives of ethyl 3-amino-1H-pyrazole-4-carboxylate.

    PubMed

    Kusakiewicz-Dawid, Anna; Masiukiewicz, Elzbieta; Rzeszotarska, Barbara; Dybała, Izabela; Kozioł, Anna Eugenia; Broda, Małgorzata Anna

    2007-05-01

    Ethyl 3-amino-1H-pyrazole-4-carboxylate (1) was yielded through total synthesis and reacted with acetic anhydride to give the acetylated products 2-6. Compounds 1-6 were studied with HPLC, X-ray, FT-IR, (1)H-NMR, (13)C-NMR and MS. Acetylation was carried out in solvents of various polarity, namely; chloroform; dioxane; DMF; acetic anhydride, at room temperature and at boiling points; and in the presence and absence of DMAP. The acetylated products are mainly nitrogen atoms in the ring. The position of the ring proton in the solution was based on NOESY; multinuclear HMBC, HSQC spectra and calculations. For equivalent amounts (1-1.5 mol) of acetic anhydride at room temperature two products of monoacetylation are produced in the ring: 2 and 3, ca. 2 : 1 and at the same time only small amount of the third product of monoacetylated, 5 in DMF, as well the product diacetylated, 4. The greatest amount of the product 4 is produced during the reaction with chloroform. However, in this solvent and in dioxane no product 5 is produced. Compound 2 is, largely, formed in dimethylformamide, in the presence DMAP, 0.2 eq. In the presence of this catalytic base, for the first hour, there is a mixture 2 and 3 to the ratio ca. 95 : 5. With 8 eq of Ac(2)O at reflux, after another hour, the compounds 3, 4 and 6 appear about equal amounts. After a longer time, the compound, which appears most in this mixture is triacetylated derivative 6. The structural and spectroscopic characteristics of compounds 1-6 have been given and the methods for their preparation have been provided. PMID:17473461

  19. Replacing methyl chloroform for cleaning turbine generator components and NDE applications

    SciTech Connect

    Bailey, K.P.; O'Shanka, J.J.; Corley, T.J. . Power Generation Business Unit); Sadhir, R.K. )

    1993-08-01

    Industrial applications of methyl chloroform (1,1,1-trichloroethane) have proven to be a significant concern to the environment. As a chlorofluorocarbon (CFC), the chemical is classified by the Environmental Protection Agency as an ozone-layer-depleting substance (OLDS). CFCs are effective cleaners of organic-based materials (oils, greases, cutting fluids, etc.). The Westinghouse Power Generation Business Unit (PGBU) has taken a proactive approach to this problem and instituted two programs in 1991 and 1992 to eliminate their consumption of CFCs. The scope of the first program was to establish an alternate cleaner for the removal of oil on generator stator windings. The second program built on the work of the first program, extending the scope to include general purpose cleaning of various contaminants prior to and at the completion of nondestructive examinations (NDE). The article that follows details the methodology, results, discussions, and conclusions of the second program and the data extrapolated from the first program. The specific NDE qualification requirements are highlighted in the methodology section.

  20. Wirelike charge transport dynamics for DNA-lipid complexes in chloroform.

    PubMed

    Mishra, Ashutosh Kumar; Young, Ryan M; Wasielewski, Michael R; Lewis, Frederick D

    2014-11-01

    The dynamics of charge separation and charge recombination have been determined for lipid complexes of DNA capped hairpins possessing stilbene electron-acceptor and -donor chromophores separated by base-pair domains that vary in length and base sequence in chloroform solution by means of femtosecond time-resolved transient absorption spectroscopy. The results obtained for the DNA-lipid complexes are compared with those previously obtained in our laboratories for the same hairpins in aqueous buffer. The charge separation and charge recombination times for the lipid complexes are consistently much shorter than those determined in aqueous solution and are only weakly dependent on the number of base pairs separating the acceptor and donor. The enhanced rate constants for forward and return charge transport in DNA-lipid complexes support proposals that solvent gating is responsible, to a significant extent, for the relatively low rates of charge transport for DNA in water. Moreover, they suggest that DNA-lipid complexes may prove useful in the development of DNA-based molecular electronic devices. PMID:25299823

  1. Unexpected Temperature Behavior of Polyethylene Glycol Spacers in Copolymer Dendrimers in Chloroform

    NASA Astrophysics Data System (ADS)

    Markelov, Denis A.; Matveev, Vladimir V.; Ingman, Petri; Nikolaeva, Marianna N.; Penkova, Anastasia V.; Lahderanta, Erkki; Boiko, Natalia I.; Chizhik, Vladimir I.

    2016-04-01

    We have studied copolymer dendrimer structure: carbosilane dendrimers with terminal phenylbenzoate mesogenic groups attached by poly(ethylene) glycol (PEG) spacers. In this system PEG spacers are additional tuning to usual copolymer structure: dendrimer with terminal mesogenic groups. The dendrimer macromolecules were investigated in a dilute chloroform solution by 1H NMR methods (spectra and relaxations). It was found that the PEG layer in G = 5 generations dendrimer is “frozen” at high temperatures (above 260 K), but it unexpectedly becomes “unfrozen” at temperatures below 250 K (i.e., melting when cooling). The transition between these two states occurs within a small temperature range (~10 K). Such a behavior is not observed for smaller dendrimer generations (G = 1 and 3). This effect is likely related to the low critical solution temperature (LCST) of PEG and is caused by dendrimer conformations, in which the PEG group concentration in the layer increases with growing G. We suppose that the unusual behavior of PEG fragments in dendrimers will be interesting for practical applications such as nanocontainers or nanoreactors.

  2. Chemical compositions and antiproliferation activities of the chloroform fraction from Pyropolyporus fomentarius in K562 cells.

    PubMed

    Zhang, Y; Wang, P; Xiao, Y; Wang, X; Yang, S; Liu, Q

    2015-07-01

    Pyropolyporus fomentarius, a fungus of the polyporaceae family, has been used in the treatment of various diseases, such as gastroenteric disorder, hepatocirrhosis, oral ulcer, inflammation, and several cancers. This study was conducted to investigate the compositions and cell growth inhibition effects of P. fomentarius chloroform (CHCl3) fraction and to clarify the possible mechanisms. Gas chromatography-mass spectrometry analysis was performed to investigate the composition of the P. fomentarius CHCl3 fraction. Cell viability was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Cell membrane damage was evaluated with a scanning electron microscope and flow cytometry following propidium iodide and bis-(1,3-dibarbituric acid)-trimethine oxanol staining. Apoptosis was analyzed using annexin V-PE/7-amino-actinomycin D (7-AAD) staining. Generation of intracellular calcium ion (Ca(2+)), reactive oxygen species (ROS), and changes of mitochondrial membrane potential (Δψ m) were detected by flow cytometry using fluo 3-acetoxymethyl ester, 2',7'-dichlorofluorescin-diacetate, and rhodamine 123. Our obtained data indicate that P. fomentarius CHCl3 fraction could inhibit proliferation of K562 cells depending on both the dosage and the incubation time, cause cell membrane damage, influence intracellular [Ca(2+)]i variation, promote the yield of ROS, decrease the level of Δψ m, and initiate the apoptotic response in K562 cells. PMID:25403175

  3. Microscale analysis of amino acids using gas chromatography-mass spectrometry after methyl chloroformate derivatization.

    PubMed

    Chen, Wen-Ping; Yang, Xiao-Yuan; Hegeman, Adrian D; Gray, William M; Cohen, Jerry D

    2010-08-15

    To conduct studies of stable isotope incorporation and dilution in growing plants, a rapid microscale method for determination of amino acid profiles from minute amounts of plant samples was developed. The method involves solid-phase ion exchange followed by derivatization and analysis by gas chromatography-mass spectrometry (GC-MS). The procedure allowed the eluent to be derivatized directly with methyl chloroformate without sample lyophilization or other evaporation procedures. Sample extraction and derivatization required only ca. 30min and quantification of the 19 amino acids eluted from the cation exchange solid-phase extraction step from a single cotyledon (0.4mg fresh weight) or three etiolated 7-day-old Arabidopsis seedlings (0.1mg fresh weight) was easily accomplished in the selected ion monitoring mode. This method was especially useful for monitoring mass isotopic distribution of amino acids as illustrated by Arabidopsis seedlings that had been labeled with deuterium oxide and (15)N salts. Sample preparation was facile, rapid, economical, and the method is easily modified for integration into robotic systems for analysis with large numbers of samples. PMID:20663719

  4. Dechlorination and decomposition of chloroform induced by glow discharge plasma in an aqueous solution.

    PubMed

    Liu, Yongjun; Crittenden, John C; Wang, Lei; Liu, Panliang

    2016-05-01

    In this study, efficient dechlorination and decomposition of chloroform (CF) induced by glow discharge plasma (GDP) in contact with a sodium sulfate solution was investigated. Intermediate byproducts were determined by ionic chromatography and headspace gas chromatography, respectively. Results showed that CF can be effectively dechlorinated and decomposed under the action of GDP. Both removal and dechlorination of CF increased with increasing pH and with addition of hydroxyl radical scavengers to the solution. Addition of H2O2 to the solution slightly decreased the CF removal. Formic acid, oxalic acid and dichloromethane were determined as the major intermediate byproducts. Final products were carbon dioxide and hydrochloric acid. Hydrated electrons were the most likely active species responsible for initiation of the dechlorination, and hydroxyl radicals may be the ones for the oxidation of the organic intermediate byproducts. Hydrolyses of the chloromethyl radicals contributed much in the mineralization of the organic chlorine. Reaction mechanism was proposed based on the dechlorination kinetics and the distribution of intermediate byproducts. PMID:26808246

  5. Isolation and identification of bioactive compounds from chloroform fraction of methanolic extract of Carissa opaca roots.

    PubMed

    Ahmed, Dildar; Fatima, Khaizran; Saeed, Ramsha; Masih, Rashid

    2016-09-01

    Carissa opaca is a shrub known for its variety of medicinal applications. This study reports isolation and identification of four chemical compounds from its roots for the first time. The methanolic extract of the roots was fractionated into various solvents with increasing polarity. Chloroform fraction was subjected to column and thin layer chromatography to ultimately yield 2H-cyclopropanaphthalene-2-one, 7-hydroxy-6-methoxy-2H-1-benzopyran-2-one, 3-(4-methoxyphenyl)-2,6-dimethylbenzofuran and 5(1H)-azulenone, 2,4,6,7,8,8a-hexahydro-3,8-dimethyl-4-(1-methylethylidene)-,(8S-cis). They were identified by GC-MS analysis. The compounds exhibited considerable antimicrobial activities against Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Candida albicans and Aspergillus niger with zones of inhibition ranging from 10 to 13 mm as compared to the standard drug amoxicillin with zones of inhibition 13-17 mm under the similar conditions. In conclusion, the roots of C. opaca can provide new leads for future antimicrobial drugs. PMID:26539756

  6. RNASwift: A rapid, versatile RNA extraction method free from phenol and chloroform.

    PubMed

    Nwokeoji, Alison O; Kilby, Peter M; Portwood, David E; Dickman, Mark J

    2016-11-01

    RNASwift is an inexpensive, versatile method for the rapid extraction of RNA. Existing RNA extraction methods typically use hazardous chemicals including phenol, chloroform and formamide which are often difficult to completely remove from the extracted RNA. RNASwift uses sodium chloride and sodium dodecyl sulphate to lyse the cells and isolate the RNA from the abundant cellular components in conjunction with solid phase extraction or isopropanol precipitation to rapidly purify the RNA. Moreover, the purified RNA is directly compatible with downstream analysis. Using spectrophotometry in conjunction with ion pair reverse phase chromatography to analyse the extracted RNA, we show that RNASwift extracts and purifies RNA of higher quality and purity in comparison to alternative RNA extraction methods. The RNASwift method yields approximately 25 μg of RNA from only 10(8)Escherichia coli cells. Furthermore, RNASwift is versatile; the same simple reagents can be used to rapidly extract RNA from a variety of different cells including bacterial, yeast and mammalian cells. In addition to the extraction of total RNA, the RNASwift method can also be used to extract double stranded RNA from genetically modified E. coli in higher yields compared to alternative methods. PMID:27495141

  7. Vibrational Spectra of Chloroform, FREON-11 and Selected Isotopomers in the Terahertz Region

    NASA Astrophysics Data System (ADS)

    Haase, Christa; Liu, Jinjun; Merkt, Frédéric

    2010-06-01

    The fundamental bands of the CCl_3 asymmetric deformation modes of selected isotopomers of chloroform (CHCl_3) and freon-11 (CFCl_3) have been measured between 7 and 8 THz in a static cell at ambient temperature using a laser-based source of tunable radiation in the terahertz region (0.1-10 THz) of the electromagnetic spectrum. Simulation of the rotational contour of the ν_6 fundamental transition of 12CH35Cl_3 confirmed previously suggested values for C_6 and C_6ζ_6. The fundamental frequencies were derived with a precision of 2 GHz for all compounds except CF35Cl_3, where the precision amounted to 3 GHz. The frequencies are in agreement with values calculated ab initio. Extension of the experimental setup to enable measurement of THz spectra of molecules in supersonic jet expansions and partially resolve their rotational structure is in progress. J. H. Carpenter, P. J. Seo and D. H. Whiffen J. Mol. Spectrosc., 170, 215, (1995).

  8. Sensitive chemi-sensor for environmental applications as marker of chloroform in aqueous solution

    NASA Astrophysics Data System (ADS)

    Khan, Sher Bahadar; Faisal, M.; Rahman, Mohammed M.; Akhtar, Kalsoom; Asiri, Abdullah M.; Alamry, Khalid A.

    2013-04-01

    Sensor technology is a talented progression in the fundamental science and has vital role in the environmental and health monitoring. A lot of sensor materials with different sensitivities have been exposed but the prospective for industrial development as sensors and environmental supplement are still limited. Chloroform chemi-sensor has been fabricated by proficient exploitation of CuO microsphere as redox mediator. CuO microsphere showed good sensitivity (1.497 μM cm-2 mM-1) and lower limit of detection (LOD = 0.08 mM) with linear dynamic range (LDR) of 0.13 mM to 0.66 M in short response time (10.0 s). The hydrothermally synthesized CuO microsphere were characterized by using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and UV-vis spectra. XRD and FTIR approved that synthesized product is well crystalline, single phase monoclinic CuO. Morphological investigations revealed that CuO composed of nano-block which arranged and structured themselves in a proper manner to give sphere like micro-structures.

  9. Mode-specific intermolecular vibrational energy transfer. I. Phenyl selenocyanate and deuterated chloroform mixture

    NASA Astrophysics Data System (ADS)

    Bian, Hongtao; Li, Jiebo; Wen, Xiewen; Zheng, Junrong

    2010-05-01

    Vibrational energy transfer from the first excited state (2252 cm-1) of the C-D stretch of deuterated chloroform (DCCl3) to the 0-1 transition (2155 cm-1) of the CN stretch of phenyl selenocyanate (C6H5SeCN) in their 1:1 liquid mixture was observed with a pump/probe two-color two dimensional infrared spectroscopic technique. The mode-specific energy transfer can occur mainly because of the long vibrational lifetime of the CN stretch first excited state (˜300 ps) and the relatively strong hydrogen-bond between the C-D and CN (calculated H-bond formation energy in gas phase ˜-5.4 kcal/mol). The mode-specific energy transfer is relatively low efficient (only ˜2%), which is mainly because of the relatively short vibrational lifetime (˜9 ps) of the C-D stretch first excited state and the big donor/acceptor energy mismatch (97 cm-1) and the slow transfer kinetics (1/kCD→CN=330 ps).

  10. Antimicrobial activity of essential oils and chloroform alone and combinated with cetrimide against Enterococcus faecalis biofilm

    PubMed Central

    Ferrer Luque, Carmen Maria; González-Rodríguez, Maria Paloma; Arias-Moliz, Maria Teresa; Baca, Pilar

    2013-01-01

    Abstract The Enterococcus faecalis bacteria have been identified as the most commonly recovered species from teeth with persistent endodontic infections. The antimicrobial activity of essential oils and chloroform (CHL), alone and in association with various concentrations of cetrimide (CTR), against biofilm of Enterococcus faecalis was investigated. Solutions of CHL, eucalyptus oil (EO) and orange oil (OO) associated with CTR at 0.3%, 0.2%, 0.1%, and 0.05% were used to determine antimicrobial activity by exposing treated bovine dentine blocks to E. faecalis. Biofilms grown in the dentine blocks for 7 days were exposed to solutions for 2 and 5 min. Biofilm reduction between OO and EO at 2 min did not show any significant differences; however, OO had a higher kill percentage of biofilms than did the eucalyptus oil at 5 min (p < 0.01). Combinations with CTR at all concentrations achieved a 100% kill rate at 2 and 5 min. The association of CTR with solvent agents achieved the maximum antimicrobial activity against E. faecalis biofilms in dentine. PMID:24265917

  11. Comparative analysis of antioxidant and phenolic content of chloroform extract/fraction of Terminalia chebula

    PubMed Central

    Walia, Harpreet; Kumar, Subodh; Arora, Saroj

    2011-01-01

    In the present study, two chloroform extracts of fruits of Terminalia chebula viz. “CHL1” and “CHL 2” prepared by maceration and sequential method respectively was compared for their antioxidant efficacy and phenolic content. The extraction procedure of plant material plays an important role in the activity of phytochemicals. Also, the assessment of antioxidant capacity of phytochemicals cannot be executed precisely by any single method due to complex nature of phytochemicals as multiple reaction characteristics and mechanisms can be involved. So, no single assay could accurately reflect comparison in a mixed or complex system. Therefore in the present study the comparison of extracts was done by using most widely used assays viz. DPPH, deoxyribose, reducing power, chelating power and lipid peroxidation assay. Furthermore, the UV-Vis spectrum of both extracts and the correlation between total phenolic content was examined in order to give an orientation to the search of phytochemicals responsible for their activity. From the results, it was concluded that antioxidant activity and phenolic compounds were predominant in the ‘CHL 2’ prepared by sequential method. The present study enlightening the useful extraction procedure of plant material PMID:24826010

  12. A Large, Voltage-Dependent Channel, Isolated from Mitochondria by Water-Free Chloroform Extraction

    PubMed Central

    Pavlov, Evgeny; Zakharian, Eleonora; Bladen, Christopher; Diao, Catherine T. M.; Grimbly, Chelsey; Reusch, Rosetta N.; French, Robert J.

    2005-01-01

    We examined ion channels derived from a chloroform extract of isolated, dehydrated rat liver mitochondria. The extraction method was previously used to isolate a channel-forming complex containing poly-3-hydroxybutyrate and calcium polyphosphate from Escherichia coli. This complex is also present in eukaryotic membranes, and is located primarily in mitochondria. Reconstituted channels showed multiple subconductance levels and were voltage-dependent, showing an increased probability of higher conductance states at voltages near zero. In symmetric 150 mM KCl, the maximal conductance of the channel ranged from 350 pS to 750 pS. For voltages >±60 mV, conductance fluctuated in the range of ∼50–∼200 pS. In the presence of a 1:3 gradient of KCl, at pH = 7.4, selectivity periodically switched between different states ranging from weakly anion-selective (Vrev ∼ −15 mV) to ideally cation-selective (Vrev ∼ +29 mV), without a significant change in its conductance. Overall, the diverse, but highly reproducible, channel activity most closely resembled the behavior of the permeability transition pore channel seen in patch-clamp experiments on native mitoplasts. We suggest that the isolated complex may represent the ion-conducting module from the permeability transition pore. PMID:15695627

  13. Antiproliferative activity of chloroformic extract of Persian Shallot, Allium hirtifolium, on tumor cell lines.

    PubMed

    Ghodrati Azadi, Hamideh; Ghaffari, Seyed Mahmood; Riazi, Gholam Hossein; Ahmadian, Shahin; Vahedi, Fatemeh

    2008-03-01

    Allium hirtifolim (Persian Shallot) belongs to Allium genus (Alliaceae family). We investigated the in vitro effects of chloroformic extract of A. hirtifolium and its Allicin on the proliferation of HeLa (cervical cancer), MCF7 (human, caucasion, breast, adenocarcinoma) and L929 (mouse, C3H/An, connective) cell lines. Our results showed that components of A. hirtifolium might inhibit proliferation of tumor cell lines. This inhibition in HeLa and MCF-7 cells was dose-dependent. The presence of Allicin was evaluated by TLC method in bulbs and the extract of A. hirtifolium was analyzed by HPLC. MTT test was performed 24, 48 and 72 h after cell culture. A significant decrease in cell lines was observed in HeLa and MCF-7 as compared to L929 cell lines. DNA fragmentation analysis revealed a large number of apoptotic cells in treated HeLa and MCF-7 cell groups, but no effects in L929 cells. Therefore A. hirtifolium might be a candidate for tumor suppression. PMID:19002856

  14. Unexpected Temperature Behavior of Polyethylene Glycol Spacers in Copolymer Dendrimers in Chloroform.

    PubMed

    Markelov, Denis A; Matveev, Vladimir V; Ingman, Petri; Nikolaeva, Marianna N; Penkova, Anastasia V; Lahderanta, Erkki; Boiko, Natalia I; Chizhik, Vladimir I

    2016-01-01

    We have studied copolymer dendrimer structure: carbosilane dendrimers with terminal phenylbenzoate mesogenic groups attached by poly(ethylene) glycol (PEG) spacers. In this system PEG spacers are additional tuning to usual copolymer structure: dendrimer with terminal mesogenic groups. The dendrimer macromolecules were investigated in a dilute chloroform solution by (1)H NMR methods (spectra and relaxations). It was found that the PEG layer in G = 5 generations dendrimer is "frozen" at high temperatures (above 260 K), but it unexpectedly becomes "unfrozen" at temperatures below 250 K (i.e., melting when cooling). The transition between these two states occurs within a small temperature range (~10 K). Such a behavior is not observed for smaller dendrimer generations (G = 1 and 3). This effect is likely related to the low critical solution temperature (LCST) of PEG and is caused by dendrimer conformations, in which the PEG group concentration in the layer increases with growing G. We suppose that the unusual behavior of PEG fragments in dendrimers will be interesting for practical applications such as nanocontainers or nanoreactors. PMID:27052599

  15. Unexpected Temperature Behavior of Polyethylene Glycol Spacers in Copolymer Dendrimers in Chloroform

    PubMed Central

    Markelov, Denis A.; Matveev, Vladimir V.; Ingman, Petri; Nikolaeva, Marianna N.; Penkova, Anastasia V.; Lahderanta, Erkki; Boiko, Natalia I.; Chizhik, Vladimir I.

    2016-01-01

    We have studied copolymer dendrimer structure: carbosilane dendrimers with terminal phenylbenzoate mesogenic groups attached by poly(ethylene) glycol (PEG) spacers. In this system PEG spacers are additional tuning to usual copolymer structure: dendrimer with terminal mesogenic groups. The dendrimer macromolecules were investigated in a dilute chloroform solution by 1H NMR methods (spectra and relaxations). It was found that the PEG layer in G = 5 generations dendrimer is “frozen” at high temperatures (above 260 K), but it unexpectedly becomes “unfrozen” at temperatures below 250 K (i.e., melting when cooling). The transition between these two states occurs within a small temperature range (~10 K). Such a behavior is not observed for smaller dendrimer generations (G = 1 and 3). This effect is likely related to the low critical solution temperature (LCST) of PEG and is caused by dendrimer conformations, in which the PEG group concentration in the layer increases with growing G. We suppose that the unusual behavior of PEG fragments in dendrimers will be interesting for practical applications such as nanocontainers or nanoreactors. PMID:27052599

  16. Chloroform fraction of Euphorbia maculata has antiplatelet activity via suppressing thromboxane B2 formation.

    PubMed

    Kwon, Se-Uk; Cha, Ji-Yoon; Lee, Hoon-Yeon; Xin, Mingjie; Ji, Su-Jeong; Kim, Dae-Ki; Park, Do-Sim; Pyo, Mi-Kyung; Lee, Young-Mi

    2015-06-01

    Euphorbia maculata (EM) is a traditionally used antidiarrheal, antibacterial, antifungal and antioxidant agent. However, the effects of EM on platelet activity remain to be elucidated. Therefore, the present study investigated the antiplatelet effect of various EM extract fractions on platelet aggregation in rats. The antiplatelet activity of the EM fractions on collagen or adenosine diphosphate (ADP)‑induced platelet aggregation was evaluated in vitro and ex vivo. Thromboxane B2 (TXB2) formation, rat‑tail bleeding time and coagulation time were also measured. Among the fractions, the chloroform fraction of EM (CFEM) significantly inhibited ADP‑induced platelet aggregation in vitro. Furthermore, oral administration of 50 mg/kg CFEM to rats significantly reduced ADP‑induced platelet aggregation without increasing the tail bleeding time or coagulation time. In addition, EM significantly inhibited the level of TXB2 formation in a dose‑dependent manner. These results suggest that CFEM exhibits antiplatelet activity, without causing bleeding, via the suppression of TXB2 formation. CFEM may be a type of food which has the potential for preventing cardiovascular disease. PMID:25672843

  17. Synthesis of renewable diesel with the 2-methylfuran, butanal and acetone derived from lignocellulose.

    PubMed

    Li, Guangyi; Li, Ning; Yang, Jinfan; Wang, Aiqin; Wang, Xiaodong; Cong, Yu; Zhang, Tao

    2013-04-01

    In this work, the hydroxyalkylation/alkylation of 2-methylfuran (2-MF) with acetone and butanal was investigated over a series of solid acid catalysts. Among the investigated candidates, Nafion-212 resin demonstrated the highest activity and stability for both reactions. Butanal is more reactive than acetone in hydroxyalkylation/alkylation, which can be rationalized by the steric and electronic effects of alkyl group. Finally, the hydroxyalkylation/alkylation products as prepared were directly hydrodeoxygenated over Pd/C, Pt/C and Ni-WxC/C catalysts. Evidently higher carbon yields to diesel were obtained when hydroxyalkylation/alkylation product of 2-MF with butanal was used as the feedstock. This can be considered as another advantage of 2-MF-butanal route. It is interesting that Ni-WxC/C catalyst exhibited excellent catalytic performance and good stability in the hydrodeoxygenation of hydroxyalkylation/alkylation products, which made it a promising substitute for the noble metal catalysts. PMID:23500561

  18. Roles of Acetone and Diacetone Alcohol in Coordination and Dissociation Reactions of Uranyl Complexes

    SciTech Connect

    Rios, Daniel; Schoendorff, George E.; Van Stipdonk, Michael J.; Gordon, Mark S.; Windus, Theresa L.; Gibson, John K.; De Jong, Wibe A.

    2012-12-03

    Combined collision-induced dissociation mass-spectrometry experiments and DFT calculations were employed to elucidate the molecular structure of "hypercoordinated" species and the energetics of water-elimination reactions of uranyl acetone complexes observed in earlier work (Rios, D.; Rutkowski, P. X.; Van Stipdonk, M. J.; Gibson, J. K. Inorg. Chem. 2011, 50, 4781). It is shown that the "hypercoordinated" species contain diacetone alcohol ligands bonded in either bidentate or monodentate fashion, which are indistinguishable from (acetone)2 in mass spectrometry. Calculations confirm that four diacetone ligands can form stable complexes, but that the effective number of atoms coordinating with uranium in the equatorial plane does not exceed five. Diacetone alcohol ligands are shown to form mesityl oxide ligands and alkoxide species through the elimination of water, providing an explanation for the observed water-elimination reactions.

  19. Graphene oxide foams and their excellent adsorption ability for acetone gas

    SciTech Connect

    He, Yongqiang; Zhang, Nana; Wu, Fei; Xu, Fangqiang; Liu, Yu; Gao, Jianping

    2013-09-01

    Graphical abstract: - Highlights: • GO and RGO foams were prepared using a simple and green method, unidirectional freeze-drying. • The porous structure of the foams can be adjusted by changing GO concentrations. • GO and RGO foams show good adsorption efficiency for acetone gas. - Abstract: Graphene oxide (GO) and reduced graphene oxide (RGO) foams were prepared using a unidirectional freeze-drying method. These porous carbon materials were characterized by thermal gravimetric analysis, differential scanning calorimetry, X-ray photoelectron spectroscopy and scanning electron microscopy. The adsorption behavior of the two kinds of foams for acetone was studied. The result showed that the saturated adsorption efficiency of the GO foams was over 100%, and was higher than that of RGO foams and other carbon materials.

  20. Production of acetone, butanol, and ethanol from biomass of the green seaweed Ulva lactuca.

    PubMed

    van der Wal, Hetty; Sperber, Bram L H M; Houweling-Tan, Bwee; Bakker, Robert R C; Brandenburg, Willem; López-Contreras, Ana M

    2013-01-01

    Green seaweed Ulva lactuca harvested from the North Sea near Zeeland (The Netherlands) was characterized as feedstock for acetone, ethanol and ethanol fermentation. Solubilization of over 90% of sugars was achieved by hot-water treatment followed by hydrolysis using commercial cellulases. A hydrolysate was used for the production of acetone, butanol and ethanol (ABE) by Clostridium acetobutylicum and Clostridium beijerinckii. Hydrolysate-based media were fermentable without nutrient supplementation. C. beijerinckii utilized all sugars in the hydrolysate and produced ABE at high yields (0.35 g ABE/g sugar consumed), while C. acetobutylicum produced mostly organic acids (acetic and butyric acids). These results demonstrate the great potential of U. lactuca as feedstock for fermentation. Interestingly, in control cultures of C. beijerinckii on rhamnose and glucose, 1,2 propanediol was the main fermentation product (9.7 g/L). PMID:23201525

  1. Technical and economic assessment of processes for the production of butanol and acetone

    NASA Technical Reports Server (NTRS)

    1982-01-01

    This report represents a preliminary technical and economic evaluation of a process which produces mixed solvents (butaol/acetone/ethanol) via fermentation of sugars derived from renewable biomass resources. The objective is to assess the technology of producing butanol/acetone from biomass, and select a viable process capable of serving as a base case model for technical and economic analysis. It is anticipated that the base case process developed herein can then be used as the basis for subsequent studies concerning biomass conversion processes capable of producing a wide range of chemicals. The general criteria utilized in determining the design basis for the process are profit potential and non-renewable energy displacement potential. The feedstock chosen, aspen wood, was selected from a number of potential renewable biomass resources as the most readily available in the United States and for its relatively large potential for producing reducing sugars.

  2. Investigations on the structure of DMSO and acetone in aqueous solution

    SciTech Connect

    McLain, Sylvia E; Soper, Alan K

    2007-01-01

    Aqueous solutions of dimethyl sulfoxide (DMSO) and acetone have been investigated using neutron diffraction augmented with isotopic substitution and empirical potential structure refinement computer simulations. Each solute has been measured at two concentrations-1:20 and 1:2 solute:water mole ratios. At both concentrations for each solute, the tetrahedral hydrogen bonding network of water is largely unperturbed, though the total water molecule coordination number is reduced in the higher 1:2 concentrations. With higher concentrations of acetone, water tends to segregate into clusters, while in higher concentrations of DMSO the present study reconfirms that the structure of the liquid is dominated by DMSO-water interactions. This result may have implications for the highly nonideal behavior observed in the thermodynamic functions for 1:2 DMSO-water solutions.

  3. Proton transfer reactions between nitric acid and acetone, hydroxyacetone, acetaldehyde and benzaldehyde in the solid phase.

    PubMed

    Lasne, Jérôme; Laffon, Carine; Parent, Philippe

    2012-12-01

    The heterogeneous and homogeneous reactions of acetone, hydroxyacetone, acetaldehyde and benzaldehyde with solid nitric acid (HNO(3)) films have been studied with Reflection-Absorption Infrared Spectroscopy (RAIRS) under Ultra-High Vacuum (UHV) conditions in the 90-170 K temperature range. In the bulk or at the surface of the films, nitric acid transfers its proton to the carbonyl function of the organic molecules, producing protonated acetone-H(+), hydroxyacetone-H(+), acetaldehyde-H(+) and benzaldehyde-H(+), and nitrate anions NO(3)(-), a reaction not observed when nitric acid is previously hydrated [J. Lasne, C. Laffon and Ph. Parent, Phys. Chem. Chem. Phys., 2012, 14, 697]. This provides a molecular-scale description of the carbonyl protonation reaction in an acid medium, the first step of the acid-catalyzed condensation of carbonyl compounds, fuelling the growth of secondary organic aerosols (SOA) in the atmosphere. PMID:23090634

  4. DSC and curing kinetics study of epoxy grouting diluted with furfural -acetone slurry

    NASA Astrophysics Data System (ADS)

    Yin, H.; Sun, D. W.; Li, B.; Liu, Y. T.; Ran, Q. P.; Liu, J. P.

    2016-07-01

    The use of furfural-acetone slurry as active diluents of Bisphenol-A epoxy resin (DGEBA) groutings has been studied by dynamic and non-isothermal DSC for the first time. Curing kinetics study was investigated by non-isothermal differential scanning calorimetries at different heating rates. Activation enery (Ea) was calculated based on Kissinger and Ozawa Methods, and the results showed that Ea increased from 58.87 to 71.13KJ/mol after the diluents were added. The furfural-acetone epoxy matrix could cure completely at the theoretical curing temperature of 365.8K and the curing time of 139mins, which were determined by the kinetic model parameters.

  5. Hydrothermal Synthesis of ZnO Structures Formed by High-Aspect-Ratio Nanowires for Acetone Detection

    NASA Astrophysics Data System (ADS)

    Cao, Zhen; Wang, Yong; Li, Zhanguo; Yu, Naisen

    2016-07-01

    Snowflake-like ZnO structures originating from self-assembled nanowires were prepared by a low-temperature aqueous solution method. The as-grown hierarchical ZnO structures were investigated by X-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM). The results showed that the snowflake-like ZnO structures were composed of high-aspect-ratio nanowires. Furthermore, gas-sensing properties to various testing gases of 10 and 50 ppm were measured, which confirms that the ZnO structures were of good selectivity and response to acetone and could serve for acetone sensor to detect low-concentration acetone.

  6. Quantification of different water species in acetone using a NIR-triple-wavelength fiber laser.

    PubMed

    Andrews, Nicholas L P; MacLean, Amy G; Saunders, John E; Barnes, Jack A; Loock, Hans-Peter; Saad, Mohammed; Jia, Chenglai; Ramaswamy, Kishor; Chen, Lawrence R

    2014-08-11

    A fiber laser using a thulium-doped ZBLAN gain medium was used to generate laser radiation simultaneously at 1461, 1505 and 1874 nm, with > 5 mW output power at each of the wavelengths. The laser was used to quantify the near-infrared absorption of liquid water in acetone. Additionally, near-infrared spectra were recorded using a broad band source and were interpreted using parallel factor (PARAFAC) analysis to rationalize the concentration-dependent peak shifts. PMID:25321018

  7. The economics of acetone-butanol fermentation: theoretical and market considerations.

    PubMed

    Gapes, J R

    2000-01-01

    Acetone-butanol (AB) fermentation was once run commercially in many countries until these chemicals could be made more cheaply from fossil oil sources. Research into the revitalisation of the process has shown that the process could once again be run economically in niche markets if run in a relatively small industrial scale processing low-grade agricultural products. The following analysis is intended to help identify suitable niche markets. PMID:10937484

  8. Excess protons in water-acetone mixtures. II. A conductivity study.

    PubMed

    Semino, Rocío; Longinotti, M Paula

    2013-10-28

    In the present work we complement a previous simulation study [R. Semino and D. Laria, J. Chem. Phys. 136, 194503 (2012)] on the disruption of the proton transfer mechanism in water by the addition of an aprotic solvent, such as acetone. We provide experimental measurements of the mobility of protons in aqueous-acetone mixtures in a wide composition range, for water molar fractions, xw, between 0.05 and 1.00. Furthermore, new molecular dynamics simulation results are presented for rich acetone mixtures, which provide further insight into the proton transport mechanism in water-non-protic solvent mixtures. The proton mobility was analyzed between xw 0.05 and 1.00 and compared to molecular dynamics simulation data. Results show two qualitative changes in the proton transport composition dependence at xw ∼ 0.25 and 0.8. At xw < 0.25 the ratio of the infinite dilution molar conductivities of HCl and LiCl, Λ(0)(HCl).Λ(0)(LiCl)(-1), is approximately constant and equal to one, since the proton diffusion is vehicular and equal to that of Li(+). At xw ∼ 0.25, proton mobility starts to differ from that of Li(+) indicating that above this concentration the Grotthuss transport mechanism starts to be possible. Molecular dynamics simulation results showed that at this threshold concentration the probability of interconversion between two Eigen structures starts to be non-negligible. At xw ∼ 0.8, the infinite molar conductivity of HCl concentration dependence qualitatively changes. This result is in excellent agreement with the analysis presented in the previous simulation work and it has been ascribed to the interchange of water and acetone molecules in the second solvation shell of the hydronium ion. PMID:24182052

  9. Life tests of aluminium axial groove heat pipes with acetone as a working fluid

    NASA Astrophysics Data System (ADS)

    Lobanov, A. D.; Yatsenko, A. A.; Parfentiev, M. D.; Barkova, L. V.

    1991-12-01

    Functional acceleration and storage life test results of 70 low temperature aluminum Heat Pipes (HP) with acetone are presented. To provide long term tests at elevated temperature, thermostats on gas controlled HPs were developed ensuring that the required temperature was kept during the tests. Based on studies and test data and using the Arrhenius equation, the time was determined for which the HP can operate at specified temperature levels.

  10. Theoretical studies of mechanisms of cycloaddition reaction between difluoromethylene carbene and acetone

    NASA Astrophysics Data System (ADS)

    Lu, Xiu Hui; Yu, Hai Bin; Wu, Wei Rong; Xu, Yue Hua

    Mechanisms of the cycloaddition reaction between singlet difluoromethylene carbene and acetone have been investigated with the second-order Møller-Plesset (MP2)/6-31G* method, including geometry optimization and vibrational analysis. Energies for the involved stationary points on the potential energy surface (PES) are corrected by zero-point energy (ZPE) and CCSD(T)/6-31G* single-point calculations. From the PES obtained with the CCSD(T)//MP2/6-31G* method for the cycloaddition reaction between singlet difluoromethylene carbene and acetone, it can be predicted that path B of reactions 2 and 3 should be two competitive leading channels of the cycloaddition reaction between difluoromethylene carbene and acetone. The former consists of two steps: (i) the two reactants first form a four-membered ring intermediate, INT2, which is a barrier-free exothermic reaction of 97.8 kJ/mol; (ii) the intermediate INT2 isomerizes to a four-membered product P2b via a transition state TS2b with an energy barrier of 24.9 kJ/mol, which results from the methyl group transfer. The latter proceeds in three steps: (i) the two reactants first form an intermediate, INT1c, through a barrier-free exothermic reaction of 199.4 kJ/mol; (ii) the intermediate INT1c further reacts with acetone to form a polycyclic intermediate, INT3, which is also a barrier-free exothermic reaction of 27.4 kJ/mol; and (iii) INT3 isomerizes to a polycyclic product P3 via a transition state TS3 with an energy barrier of 25.8 kJ/mol.

  11. Perspectives for the biotechnological production of ethyl acetate by yeasts.

    PubMed

    Löser, Christian; Urit, Thanet; Bley, Thomas

    2014-06-01

    Ethyl acetate is an environmentally friendly solvent with many industrial applications. The production of ethyl acetate currently proceeds by energy-intensive petrochemical processes which are based on natural gas and crude oil without exception. Microbial synthesis of ethyl acetate could become an interesting alternative. The formation of esters as aroma compounds in food has been repeatedly reviewed, but a survey which deals with microbial synthesis of ethyl acetate as a bulk product is missing. The ability of yeasts for producing larger amounts of this ester is known for a long time. In the past, this potential was mainly of scientific interest, but in the future, it could be applied to large-scale ester production from renewable raw materials. Pichia anomala, Candida utilis, and Kluyveromyces marxianus are yeasts which convert sugar into ethyl acetate with a high yield where the latter is the most promising one. Special attention was paid to the mechanism of ester synthesis including regulatory aspects and to the maximum and expectable yield. Synthesis of much ethyl acetate requires oxygen which is usually supplied by aeration. Ethyl acetate is highly volatile so that aeration results in its phase transfer and stripping. This stripping process cannot be avoided but requires adequate handling during experimentation and offers a chance for a cost-efficient process-integrated recovery of the synthesized ester. PMID:24788328

  12. Ionizing radiation induced degradation of poly (2-methoxy-5-(2'-ethyl-hexyloxy) -1,4-phenylene vinylene) in solution

    SciTech Connect

    Bronze-Uhle, E. S.; Batagin-Neto, A.; Lavarda, F. C.; Graeff, C. F. O.

    2011-10-01

    In this paper we investigate the causes of the chromatic alteration observed in chloroform solutions of poly (2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene) (MEH-PPV) after gamma ray irradiation. Structural and chemical changes were analyzed by gel permeation chromatography, fourier transform infrared spectroscopy, and proton nuclear magnetic resonance techniques and complemented by electronic structure calculations. The results indicate chlorine incorporation in the polymer structure and main chain scission after irradiation. Based on our findings we propose that the main mechanism for the blue-shifts, observed in the UV-Vis absorption spectra of MEH-PPV after irradiation, is the result of a radical attack on the polymer main chain. Gamma rays generate radicals, Cl and CHCl{sub 2} from chloroform radiolysis that attack preferentially the vinyl double bonds of the polymer backbone, breaking the electronic conjugation and eventually the chain. Our results indicate that oxygen does not play a major role in the effect. Electronic spectra simulations were performed based on these assumptions reproducing the UV-Vis experimental results.

  13. Ionizing radiation induced degradation of poly (2-methoxy-5-(2'-ethyl-hexyloxy) -1,4-phenylene vinylene) in solution

    NASA Astrophysics Data System (ADS)

    Bronze-Uhle, E. S.; Batagin-Neto, A.; Lavarda, F. C.; Graeff, C. F. O.

    2011-10-01

    In this paper we investigate the causes of the chromatic alteration observed in chloroform solutions of poly (2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene) (MEH-PPV) after gamma ray irradiation. Structural and chemical changes were analyzed by gel permeation chromatography, fourier transform infrared spectroscopy, and proton nuclear magnetic resonance techniques and complemented by electronic structure calculations. The results indicate chlorine incorporation in the polymer structure and main chain scission after irradiation. Based on our findings we propose that the main mechanism for the blue-shifts, observed in the UV-Vis absorption spectra of MEH-PPV after irradiation, is the result of a radical attack on the polymer main chain. Gamma rays generate radicals, •Cl and •CHCl2 from chloroform radiolysis that attack preferentially the vinyl double bonds of the polymer backbone, breaking the electronic conjugation and eventually the chain. Our results indicate that oxygen does not play a major role in the effect. Electronic spectra simulations were performed based on these assumptions reproducing the UV-Vis experimental results.

  14. Inhalation developmental toxicology studies: Teratology study of acetone in mice and rats: Final report

    SciTech Connect

    Mast, T.J.; Evanoff, J.J.; Rommereim, R.L.; Stoney, K.H.; Weigel, R.J.; Westerberg, R.B.

    1988-11-01

    Acetone, an aliphatic ketone, is a ubiquitous industrial solvent and chemical intermediate; consequently, the opportunity for human exposure is high. The potential for acetone to cause developmental toxicity was assessed in Sprague-Dawley rats exposed to 0, 440, 2200, or 11000 ppm, and in Swiss (CD-1) mice exposed to 0, 440, 2200, and 6600 ppm acetone vapors, 6 h/day, 7 days/week. Each of the four treatment groups consisted of 10 virgin females (for comparison), and approx.32 positively mated rats or mice. Positively mated mice were exposed on days 6-17 of gestation (dg), and rats on 6-19 dg. The day of plug or sperm detection was designated as 0 dg. Body weights were obtained throughout the study period, and uterine and fetal body weights were obtained at sacrifice (rats, 20 dg; mice, 18 dg). Implants were enumerated and their status recorded. Live fetuses were sexed and examined for gross, visceral, skeletal, and soft-tissue craniofacial defects. 46 refs., 6 figs., 27 tabs.

  15. Multinuclear NMR spectroscopy for differentiation of molecular configurations and solvent properties between acetone and dimethyl sulfoxide

    NASA Astrophysics Data System (ADS)

    Wen, Yuan-Chun; Kuo, Hsiao-Ching; Jia, Hsi-Wei

    2016-04-01

    The differences in molecular configuration and solvent properties between acetone and dimethyl sulfoxide (DMSO) were investigated using the developed technique of 1H, 13C, 17O, and 1H self-diffusion liquid state nuclear magnetic resonance (NMR) spectroscopy. Acetone and DMSO samples in the forms of pure solution, ionic salt-added solution were used to deduce their active sites, relative dipole moments, dielectric constants, and charge separations. The NMR results suggest that acetone is a trigonal planar molecule with a polarized carbonyl double bond, whereas DMSO is a trigonal pyramidal-like molecule with a highly polarized S-O single bond. Both molecules use their oxygen atoms as the active sites to interact other molecules. These different molecular models explain the differences their physical and chemical properties between the two molecules and explain why DMSO is classified as an aprotic but highly dipolar solvent. The results are also in agreement with data obtained using X-ray diffraction, neutron diffraction, and theoretical calculations.

  16. Research into acetone removal from air by biofiltration using a biofilter with straight structure plates

    PubMed Central

    Baltrėnas, Pranas; Zagorskis, Alvydas; Misevičius, Antonas

    2015-01-01

    The biological air treatment method is based on the biological destruction of organic compounds using certain cultures of microorganisms. This method is simple and may be applied in many branches of industry. The main element of biological air treatment devices is a filter charge. Tests were carried out using a new-generation laboratory air purifier with a plate structure. This purifier is called biofilter. The biofilter has a special system for packing material humidification which does not require additional energy inputs. In order to extend the packing material's durability, it was composed of thermally treated birch fibre. Pollutant (acetone) biodegradation occurred on thermally treated wood fibre in this research. According to the performed tests and the received results, the process of biodestruction was highly efficient. When acetone was passed through biofilter's packing material at 0.08 m s−1 rate, the efficiency of the biofiltration process was from 70% up to 90%. The species of bacteria capable of removing acetone vapour from the air, i.e. Bacillus (B. cereus, B. subtilis), Pseudomonas (P. aeruginosa, P. putida), Stapylococcus (S. aureus) and Rhodococcus sp., was identified in this study during the process of biofiltration. Their amount in the biological packing material changed from 1.6 × 107 to 3.7 × 1011 CFU g−1. PMID:26019659

  17. Acetone as a greener alternative to acetonitrile in liquid chromatographic fingerprinting.

    PubMed

    Funari, Cristiano Soleo; Carneiro, Renato Lajarim; Khandagale, Manish M; Cavalheiro, Alberto José; Hilder, Emily F

    2015-05-01

    A considerable amount of chemical waste from liquid chromatography analysis is generated worldwide. Acetonitrile is the most employed solvent in liquid chromatography analyses since it exhibits favorable physicochemical properties for separation and detection, but it is an unwelcome solvent from an environmental point of view. Acetone might be a much greener alternative to replace acetonitrile in reversed-phase liquid chromatography, since both share similar physicochemical properties, but its applicability with ultraviolet absorbance-based detectors is limited. In this work, a reference method using acetonitrile and high-performance liquid chromatography coupled to an ultraviolet photodiode array detector coupled to a corona charged aerosol detector system was developed to fingerprint a complex sample. The possibility of effectively substituting acetonitrile with acetone was investigated. Design of experiments was adopted to maximize the number of peaks acquired in both fingerprint developments. The methods with acetonitrile or acetone were successfully optimized and proved to be statistically similar when only the number of peaks or peak capacity was taken into consideration. However, the superiority of the latter was evidenced when parameters of separation and those related to greenness were heuristically combined. A green, comprehensive, time- and resource-saving approach is presented here, which is generic and applicable to other complex matrices. Furthermore, it is in line with environmental legislation and analytical trends. PMID:25708832

  18. Nesterenkonia sp. strain F, a halophilic bacterium producing acetone, butanol, and ethanol under aerobic conditions

    PubMed Central

    Amiri, Hamid; Azarbaijani, Reza; Parsa Yeganeh, Laleh; Shahzadeh Fazeli, Abolhassan; Tabatabaei, Meisam; Hosseini Salekdeh, Ghasem; Karimi, Keikhosro

    2016-01-01

    The moderately halophilic bacterium Nesterenkonia sp. strain F, which was isolated from Aran-Bidgol Lake (Iran), has the ability to produce acetone, butanol, and ethanol (ABE) as well as acetic and butyric acids under aerobic and anaerobic conditions. This result is the first report of ABE production with a wild microorganism from a family other than Clostridia and also the first halophilic species shown to produce butanol under aerobic cultivation. The cultivation of Nesterenkonia sp. strain F under anaerobic conditions with 50 g/l of glucose for 72 h resulted in the production of 105 mg/l of butanol, 122 mg/l of acetone, 0.2 g/l of acetic acid, and 2.5 g/l of butyric acid. Furthermore, the strain was cultivated on media with different glucose concentrations (20, 50, and 80 g/l) under aerobic and anaerobic conditions. Through fermentation with a 50 g/l initial glucose concentration under aerobic conditions, 66 mg/l of butanol, 125 mg/l of acetone, 291 mg/l of ethanol, 5.9 g/l of acetic acid, and 1.2 g/l of butyric acid were produced. The enzymes pertaining to the fermentation pathway in the strain were compared with the enzymes of Clostridium spp., and the metabolic pathway of fermentation used by Nesterenkonia sp. strain F was investigated. PMID:26725518

  19. Acetone in theGlobal Troposphere: Its Possible Role as a Global Source of PAN

    NASA Technical Reports Server (NTRS)

    Singh, H. B.; Kanakidou, M.

    1994-01-01

    Oxygenated hydrocarbons are thought to be important components of the atmosphere but, with the exception of formaldehyde, very little about their distribution and fate is known. Aircraft measurements of acetone (CH3COCH3), PAN (CH3CO3NO2) and other organic species (e. g. acetaldehyde, methanol and ethanol) have been performed over the Pacific, the southern Atlantic, and the subarctic atmospheres. Sampled areas extended from 0 to 12 km altitude over latitudes of 70 deg N to 40 deg S. All measurements are based on real time in-situ analysis of cryogenically preconcentrated air samples. Substantial concentrations of these oxygenated species (10-2000 ppt) have been observed at all altitudes and geographical locations in the troposphere. Important sources include, emissions from biomass burning, plant and vegetation, secondary oxidation of primary non-methane hydrocarbons, and man-made emissions. Direct measurements within smoke plumes have been used to estimate the biomass burning source. Photochemistry studies are used to suggest that acetone could provide a major source of peroxyacetyl radicals in the atmosphere and play an important role in sequestering reactive nitrogen. Model calculations show that acetone photolysis contributes significantly to PAN formation in the middle and upper troposphere.

  20. Nesterenkonia sp. strain F, a halophilic bacterium producing acetone, butanol, and ethanol under aerobic conditions.

    PubMed

    Amiri, Hamid; Azarbaijani, Reza; Parsa Yeganeh, Laleh; Shahzadeh Fazeli, Abolhassan; Tabatabaei, Meisam; Salekdeh, Ghasem Hosseini; Karimi, Keikhosro

    2016-01-01

    The moderately halophilic bacterium Nesterenkonia sp. strain F, which was isolated from Aran-Bidgol Lake (Iran), has the ability to produce acetone, butanol, and ethanol (ABE) as well as acetic and butyric acids under aerobic and anaerobic conditions. This result is the first report of ABE production with a wild microorganism from a family other than Clostridia and also the first halophilic species shown to produce butanol under aerobic cultivation. The cultivation of Nesterenkonia sp. strain F under anaerobic conditions with 50 g/l of glucose for 72 h resulted in the production of 105 mg/l of butanol, 122 mg/l of acetone, 0.2 g/l of acetic acid, and 2.5 g/l of butyric acid. Furthermore, the strain was cultivated on media with different glucose concentrations (20, 50, and 80 g/l) under aerobic and anaerobic conditions. Through fermentation with a 50 g/l initial glucose concentration under aerobic conditions, 66 mg/l of butanol, 125 mg/l of acetone, 291 mg/l of ethanol, 5.9 g/l of acetic acid, and 1.2 g/l of butyric acid were produced. The enzymes pertaining to the fermentation pathway in the strain were compared with the enzymes of Clostridium spp., and the metabolic pathway of fermentation used by Nesterenkonia sp. strain F was investigated. PMID:26725518

  1. Acetone Sensing by Modified SnO2 Nanocrystalline Sensor Materials

    NASA Astrophysics Data System (ADS)

    Krivetsky, V. V.; Petukhov, D. V.; Eliseev, A. A.; Smirnov, A. V.; Rumyantseva, M. N.; Gaskov, Aleksandre M.

    A complementary gas sensor and gas chromatography/mass spectrometry study was performed to investigate the chemical basis of acetone vapor sensing via semiconductor metal oxide gas sensors. The effect of additives to nanocrystalline SnO2-based sensor materials was analyzed. The main process that contributes to the electrical yield of this interaction and thus to the sensor response is a complete acetone oxidation to CO2and H2O. At the same time it is clearly shown that this sensor response is severely limited by the rate of desorption of the reaction products. The main contributors to this negative influence on the sensor response are heavy organic compounds with molar masses larger than that of acetone. It is also shown that their negative effect could be mitigated by the incorporation of catalytic clusters of gold on the surface of SnO2based sensor materials. This kind of catalyst acts either as a preventor of the formation of heavy and complex organic molecules on the sensor surface or as a combustion catalyst, which facilitates their decomposition.

  2. A Ringdown Breath Analyzer for Diabetes Monitoring: Breath Acetone in Diabetic Patients.

    NASA Astrophysics Data System (ADS)

    Wang, Chuji; Mbi, Armstrong; Shepherd, Mark

    2008-03-01

    It is highly desirable for millions of diabetic patients to have a non-blood, non-invasive, point-of-care device for monitoring daily blood glucose (BG) levels and the adequacy of diabetic treatment and control. Cavity ringdown spectroscopy, due to its unique capability of high sensitivity, fast-response, and relatively low cost for instrumentation, has the potential for medical application through non-invasive analysis of breath biomarkers. We report the first ringdown acetone breath analyzer for clinic testing with diabetic outpatients. The instrument was set in a clinic center and 34 outpatients (24 T1D and 10 T2D) were tested during a four-day period. 10 T1D subjects and 15 nondiabetic persons were tested in our laboratory. Three juvenile-onset T1D subjects were selected for a 24-hr monitoring on the variations of breath acetone and simultaneous BG level. In this talk, we present our research findings including the correlations of breath acetone with BG level and A1C.

  3. Purification of xylitol from fermented hemicellulosic hydrolyzate using liquid-liquid extraction and precipitation techniques.

    PubMed

    Mussatto, Solange I; Santos, Júlio C; Filho, Walter C Ricardo; Silva, Silvio S

    2005-08-01

    Xylitol was produced by Candida guilliermondii by fermentation of sugarcane bagasse hemicellulosic hydrolysate. Undesirable impurities were extracted from the broth using either ethyl acetate, chloroform or dichloromethane. The best results on clarification of the broth without xylitol loss were obtained with ethyl acetate. When ethanol, acetone or tetrahydrofuran were used for precipitation of impurities, only tetrahydrofuran clarified the fermented broth, but a high xylitol loss (approximately 30%) was observed. PMID:16132861

  4. Ethyl pyruvate protects colonic anastomosis from ischemia-reperfusion injury.

    PubMed

    Unal, B; Karabeyoglu, M; Huner, T; Canbay, E; Eroglu, A; Yildirim, O; Dolapci, M; Bilgihan, A; Cengiz, O

    2009-03-01

    Ethyl pyruvate is a simple derivative in Ca(+2)- and K(+)-containing balanced salt solution of pyruvate to avoid the problems associated with the instability of pyruvate in solution. It has been shown to ameliorate the effects of ischemia-reperfusion (I/R) injury in many organs. It has also been shown that I/R injury delays the healing of colonic anastomosis. In this study, the effect of ethyl pyruvate on the healing of colon anastomosis and anastomotic strength after I/R injury was investigated. Anastomosis of the colon was performed in 32 adult male Wistar albino rats divided into 4 groups of 8 individuals: (1) sham-operated control group (group 1); (2) 30 minutes of intestinal I/R by superior mesenteric artery occlusion (group 2); (3) I/R+ ethyl pyruvate (group 3), ethyl pyruvate was administered as a 50-mg/kg/d single dose; and (4) I/R+ ethyl pyruvate (group 4), ethyl pyruvate administration was repeatedly (every 6 hours) at the same dose (50 mg/kg). On the fifth postoperative day, animals were killed. Perianastomotic tissue hydroxyproline contents and anastomotic bursting pressures were measured in all groups. When the anastomotic bursting pressures and tissue hydroxyproline contents were compared, it was found that they were decreased in group 2 when compared with groups 1, 3, and 4 (P < .05). Both anastomotic bursting pressure (P = .005) and hydroxyproline content (P < .001) levels were found to be significantly increased with ethyl pyruvate administration when compared with group 2. When ethyl pyruvate administration doses were compared, a significant difference was not observed (P > .05). Ethyl pyruvate significantly prevents the delaying effect of I/R injury on anastomotic strength and healing independent from doses of administration. PMID:19064591

  5. On the cause of low thermal stability of ethyl halodiazoacetates

    PubMed Central

    Mortén, Magnus; Hennum, Martin

    2016-01-01

    Summary Rates for the thermal decomposition of ethyl halodiazoacetates (halo = Cl, Br, I) have been obtained, and reported herein are their half-lives. The experimental results are supported by DFT calculations, and we provide a possible explanation for the reduced thermal stability of ethyl halodiazoacetates compared to ethyl diazoacetate and for the relative decomposition rates between the chloro, bromo and iodo analogs. We have also briefly studied the thermal, non-catalytic cyclopropanation of styrenes and compared the results to the analogous Rh(II)-catalyzed reactions. PMID:27559411

  6. On the cause of low thermal stability of ethyl halodiazoacetates.

    PubMed

    Mortén, Magnus; Hennum, Martin; Bonge-Hansen, Tore

    2016-01-01

    Rates for the thermal decomposition of ethyl halodiazoacetates (halo = Cl, Br, I) have been obtained, and reported herein are their half-lives. The experimental results are supported by DFT calculations, and we provide a possible explanation for the reduced thermal stability of ethyl halodiazoacetates compared to ethyl diazoacetate and for the relative decomposition rates between the chloro, bromo and iodo analogs. We have also briefly studied the thermal, non-catalytic cyclopropanation of styrenes and compared the results to the analogous Rh(II)-catalyzed reactions. PMID:27559411

  7. Dynamic real-time monitoring of chloroform in an indoor swimming pool air using open-path Fourier transform infrared spectroscopy.

    PubMed

    Chen, M-J; Duh, J-M; Shie, R-H; Weng, J-H; Hsu, H-T

    2016-06-01

    This study used open-path Fourier transform infrared (OP-FTIR) spectroscopy to continuously assess the variation in chloroform concentrations in the air of an indoor swimming pool. Variables affecting the concentrations of chloroform in air were also monitored. The results showed that chloroform concentrations in air varied significantly during the time of operation of the swimming pool and that there were two peaks in chloroform concentration during the time of operation of the pool. The highest concentration was at 17:30, which is coincident with the time with the highest number of swimmers in the pool in a day. The swimmer load was one of the most important factors influencing the chloroform concentration in the air. When the number of swimmers surpassed 40, the concentrations of chloroform were on average 4.4 times higher than the concentration measured without swimmers in the pool. According to the results of this study, we suggest that those who swim regularly should avoid times with highest number of swimmers, in order to decrease the risk of exposure to high concentrations of chloroform. It is also recommended that an automatic mechanical ventilation system is installed to increase the ventilation rate during times of high swimmer load. PMID:25916255

  8. Bioassay-guided fractionation and in vivo antiplasmodial effect of fractions of chloroform extract of Artemisia maciverae Linn.

    PubMed

    Ene, A C; Atawodi, S E; Ameh, D A; Ndukwe, G I; Kwanashie, H O

    2009-12-01

    In the search for new plant-derived anti-malarial compounds, chromatographic fractions of chloroform extract of whole plants of Artemisia maciverae were tested in vivo using chloroquine resistant and chloroquine sensitive Plasmodium berghei NK 65 infected Swiss albino mice. One fraction and a sub-fraction of this were most active at 10/mg and cleared parasitemia in mice within 3 days. The different fractions and sub-fractions were tested with different reagents to determine the broad classes of compounds present. The active fraction tested positive for triterpenes and alkaloids, and the sub-fraction for only triterpenes. These tests suggest that the anti-malarial activities observed with these fractions may be due to these classes of compounds in the chloroform extract of the A. maciverae. Further chemical work is however required to characterize the active constituents. PMID:19695214

  9. Oxidation of trichloroethylene, 1,1-dichloroethylene, and chloroform by toluene/o-xylene monooxygenase from Pseudomonas stutzeri OX1

    SciTech Connect

    Chauhan, S.; Wood, T.K.; Barbieri, P.

    1998-08-01

    Toluene/o-xylene monooxygenase (ToMO) from Pseudomonas stutzeri OX1, which oxidizes toluene and o-xylene, was examined for its ability to degrade the environmental pollutants trichloroethylene (TCE), 1,1-dichloroethylene (1,1-DCE), cis-1,2-DCE, trans-1,2-DCE, chloroform, dichloromethane, phenol, 2,4-dichlorophenol, 2,4,5-trichlorophenol, 2,4,6-trichlorophenol, 2,3,5,6-tetrachlorophenol, and 2,3,4,5,6-pentachlorophenol. Escherichia coli JM109 that expressed ToMO from genes on plasmid pBZ1260 under control of the lac promoter degraded TCE, 1,1-DCE, and chloroform at initial rates of 3.1, 3.6, and 1.6 nmol, respectively. Stoichiometric amounts of chloride release were seen, indicating mineralization. Thus, the substrate range of ToMO is extended to include aliphatic chlorinated compounds.

  10. Acetone poisoning

    MedlinePlus

    ... unconscious, unresponsive) Drowsiness Stupor (confusion, decreased level of consciousness) Lack of coordination BREATHING (RESPIRATORY) SYSTEM Difficulty breathing Slowed breathing rate Shortness of breath ...

  11. First Discovery of Acetone Extract from Cottonseed Oil Sludge as a Novel Antiviral Agent against Plant Viruses

    PubMed Central

    Zhao, Lei; Feng, Chaohong; Hou, Caiting; Hu, Lingyun; Wang, Qiaochun; Wu, Yunfeng

    2015-01-01

    A novel acetone extract from cottonseed oil sludge was firstly discovered against plant viruses including Tobacco mosaic virus (TMV), Rice stripe virus (RSV) and Southern rice black streaked dwarf virus (SRBSDV). Gossypol and β-sitosterol separated from the acetone extract were tested for their effects on anti-TMV and analysed by nuclear magnetic resonance (NMR) assay. In vivo and field trials in different geographic distributions and different host varieties declared that this extract mixture was more efficient than the commercial agent Ningnanmycin with a broad spectrum of anti-plant-viruses activity. No phytotoxic activity was observed in the treated plants and environmental toxicology showed that this new acetone extract was environmentally friendly, indicating that this acetone extract has potential application in the control of plant virus in the future. PMID:25705894

  12. Triacetonamine formation in a bio-oil from fast pyrolysis of sewage sludge using acetone as the absorption solvent.

    PubMed

    Cao, Jing-Pei; Zhao, Xiao-Yan; Morishita, Kayoko; Li, Liu-Yun; Xiao, Xian-Bin; Obara, Ryoji; Wei, Xian-Yong; Takarada, Takayuki

    2010-06-01

    A sewage sludge sample was pyrolyzed in a drop tube furnace at 500 degrees C and sweeping gas flow rate of 300cm(3)/min. Triacetonamine (TAA) was detected with GC/MS as major component in the resulting bio-oil using acetone as the absorption solvent and proven to be a product from the reaction of NH(3) in the bio-oil with the absorption solvent acetone. TAA yield increased with storage time and reached a level about 28.4% (% sludge fed, daf) after 175h. Since the reaction of pure NH(3) with acetone does not proceed, some species in the bio-oil must catalyze the reaction of NH(3) with acetone. TAA was isolated in a high yield (27.9%, daf) and high purity (80.4%) by column chromatography with different solvents, including mixed solvents, as eluants. The study revealed the possibility of sewage sludge as potential resource of TAA. PMID:20137920

  13. Kinetic study of the reaction of the hydroxyl radical (OH) with methyl ethyl ketone (2-butanone) and its deuterated isotopomers at low pressure

    NASA Astrophysics Data System (ADS)

    Liljegren, J. A.; Stevens, P. S.

    2012-12-01

    Methyl ethyl ketone (2-butanone) in the atmosphere comes from a variety of sources. It is produced commercially as an industrial ketone. It can be formed as a result of the OH or Cl-initiated oxidation of C4-C6 alkanes, primarily n-butane, or from the reaction of some alkenes with OH or O3. Biogenic sources include direct emissions from certain plants as well as emissions from decaying plant matter. Methyl ethyl ketone is removed from the atmosphere primarily by its reaction with OH. A product of this reaction includes acetaldehyde, which is a hazardous air pollutant, can further react to produce peroxy acetyl nitrate (PAN), and can be a significant source of free radicals to the atmosphere. The absolute rate constant for the reaction of OH with methyl ethyl ketone has been measured as a function of temperature at low pressure using discharge-flow techniques coupled with laser induced fluorescence (LIF) detection of OH. In addition, measurements of the rate constants for the reactions of OH with two deuterated isotopomers of methyl ethyl ketone, including CD3C(O)CH2CH3 and CH3C(O)CD2CD3, will be presented to gain a better understanding of the mechanism for this reaction. Theoretical studies of the potential energy surface for this reaction suggest that the reaction proceeds through the formation of a hydrogen-bonded pre-reactive complex, similar to that of several other atmospherically relevant oxygenated VOCs such as acetone, acetic acid, and hydroxyacetone.

  14. Co-production of acetone and ethanol with molar ratio control enables production of improved gasoline or jet fuel blends.

    PubMed

    Baer, Zachary C; Bormann, Sebastian; Sreekumar, Sanil; Grippo, Adam; Toste, F Dean; Blanch, Harvey W; Clark, Douglas S

    2016-10-01

    The fermentation of simple sugars to ethanol has been the most successful biofuel process to displace fossil fuel consumption worldwide thus far. However, the physical properties of ethanol and automotive components limit its application in most cases to 10-15 vol% blends with conventional gasoline. Fermentative co-production of ethanol and acetone coupled with a catalytic alkylation reaction could enable the production of gasoline blendstocks enriched in higher-chain oxygenates. Here we demonstrate a synthetic pathway for the production of acetone through the mevalonate precursor hydroxymethylglutaryl-CoA. Expression of this pathway in various strains of Escherichia coli resulted in the co-production of acetone and ethanol. Metabolic engineering and control of the environmental conditions for microbial growth resulted in controllable acetone and ethanol production with ethanol:acetone molar ratios ranging from 0.7:1 to 10.0:1. Specifically, use of gluconic acid as a substrate increased production of acetone and balanced the redox state of the system, predictively reducing the molar ethanol:acetone ratio. Increases in ethanol production and the molar ethanol:acetone ratio were achieved by co-expression of the aldehyde/alcohol dehydrogenase (AdhE) from E. coli MG1655 and by co-expression of pyruvate decarboxylase (Pdc) and alcohol dehydrogenase (AdhB) from Z. mobilis. Controlling the fermentation aeration rate and pH in a bioreactor raised the acetone titer to 5.1 g L(-1) , similar to that obtained with wild-type Clostridium acetobutylicum. Optimizing the metabolic pathway, the selection of host strain, and the physiological conditions employed for host growth together improved acetone titers over 35-fold (0.14-5.1 g/L). Finally, chemical catalysis was used to upgrade the co-produced ethanol and acetone at both low and high molar ratios to higher-chain oxygenates for gasoline and jet fuel applications. Biotechnol. Bioeng. 2016;113: 2079-2087. © 2016 Wiley

  15. Estimates of European emissions of methyl chloroform using a Bayesian inversion method

    NASA Astrophysics Data System (ADS)

    Maione, M.; Graziosi, F.; Arduini, J.; Furlani, F.; Giostra, U.; Blake, D. R.; Bonasoni, P.; Fang, X.; Montzka, S. A.; O'Doherty, S. J.; Reimann, S.; Stohl, A.; Vollmer, M. K.

    2014-09-01

    Methyl chloroform (MCF) is a man-made chlorinated solvent contributing to the destruction of stratospheric ozone and is controlled under the "Montreal Protocol on Substances that Deplete the Ozone Layer" and its amendments, which called for its phase-out in 1996 in developed countries and 2015 in developing countries. Long-term, high-frequency observations of MCF carried out at three European sites show a constant decline in the background mixing ratios of MCF. However, we observe persistent non-negligible mixing ratio enhancements of MCF in pollution episodes, suggesting unexpectedly high ongoing emissions in Europe. In order to identify the source regions and to give an estimate of the magnitude of such emissions, we have used a Bayesian inversion method and a point source analysis, based on high-frequency long-term observations at the three European sites. The inversion identified southeastern France (SEF) as a region with enhanced MCF emissions. This estimate was confirmed by the point source analysis. We performed this analysis using an 11-year data set, from January 2002 to December 2012. Overall, emissions estimated for the European study domain decreased nearly exponentially from 1.1 Gg yr-1 in 2002 to 0.32 Gg yr-1 in 2012, of which the estimated emissions from the SEF region accounted for 0.49 Gg yr-1 in 2002 and 0.20 Gg yr-1 in 2012. The European estimates are a significant fraction of the total semi-hemisphere (30-90° N) emissions, contributing a minimum of 9.8% in 2004 and a maximum of 33.7% in 2011, of which on average 50% are from the SEF region. On the global scale, the SEF region is thus responsible for a minimum of 2.6% (in 2003) and a maximum of 10.3% (in 2009) of the global MCF emissions.

  16. Estimates of European emissions of methyl chloroform using a Bayesian inversion method

    NASA Astrophysics Data System (ADS)

    Maione, M.; Graziosi, F.; Arduini, J.; Furlani, F.; Giostra, U.; Blake, D. R.; Bonasoni, P.; Fang, X.; Montzka, S. A.; O'Doherty, S. J.; Reimann, S.; Stohl, A.; Vollmer, M. K.

    2014-03-01

    Methyl chloroform (MCF) is a man-made chlorinated solvent contributing to the destruction of stratospheric ozone and is controlled under the Montreal Protocol on Substances that Deplete the Ozone Layer. Long-term, high-frequency observations of MCF carried out at three European sites show a constant decline of the background mixing ratios of MCF. However, we observe persistent non-negligible mixing ratio enhancements of MCF in pollution episodes suggesting unexpectedly high ongoing emissions in Europe. In order to identify the source regions and to give an estimate of the magnitude of such emissions, we have used a Bayesian inversion method and a point source analysis, based on high-frequency long-term observations at the three European sites. The inversion identified south-eastern France (SEF) as a region with enhanced MCF emissions. This estimate was confirmed by the point source analysis. We performed this analysis using an eleven-year data set, from January 2002 to December 2012. Overall emissions estimated for the European study domain decreased nearly exponentially from 1.1 Gg yr-1 in 2002 to 0.32 Gg yr-1 in 2012, of which the estimated emissions from the SEF region accounted for 0.49 Gg yr-1 in 2002 and 0.20 Gg yr-1 in 2012. The European estimates are a significant fraction of the total semi-hemisphere (30-90° N) emissions, contributing a minimum of 9.8% in 2004 and a maximum of 33.7% in 2011, of which on average 50% are from the SEF region. On the global scale, the SEF region is thus responsible from a minimum of 2.6% (in 2003) to a maximum of 10.3% (in 2009) of the global MCF emissions.

  17. Simulation of maturity and decay of methyl chloroform (CH3CCl3) in the atmosphere

    NASA Astrophysics Data System (ADS)

    Patra, P. K.; Krol, M.; Cunnold, D.; Fraser, P. J.; O'Doherty, S. J.; Prinn, R. G.; Simmonds, P. G.; Steele, P.; Weiss, R. F.; Krummel, P. B.; Lal, S.; Toyoda, S.; Takigawa, M.; Ishijima, K.; Nakazawa, T.

    2009-12-01

    We have used an AGCM (atmospheric general circulation model)-based Chemistry Transport Model (ACTM) for the simulation of methyl chloroform (MCF) in the height range from the earth’s surface to about 90 km. The model MCF loss rate due to reaction with hydroxyl (OH) radical is calculated based on an optimized OH field for MCF simulations using another transport model (TM5), and loss due to photolysis is parameterized in ACTM based on JPL published absorption cross-sections. The model simulations reconstruct the measurements at hourly, daily, monthly and interannual time scales near the surface at 5 AGAGE network sites (Mace Head, Ireland; Trinidad Head, USA; Ragged Point, Barbados; Cape Matatula, American Samoa; Cape Grim, Tasmania), and the balloon-borne measurements of vertical profiles in the stratosphere from Hyderabad (India), Sanriku (Japan) and GAP (France) on event basis. By modifying the MCF emission rates to match the tropospheric growth rates at the surface, the wide range (up to 120%; McCulloch and Midgley, 2001) in the uncertainty in 'bottom-up' estimates can be narrowed significantly (to 20% or less) using ACTM and TM5 models for the period of 1990-2006. The stratospheric balloon profiles are used to validate the MCF loss rate derived in the ACTM in the stratosphere. ACTM simulations are used to show the development of a MCF layer in the tropical upper troposphere during the northern hemisphere summer, where it has relatively long lifetime, when the modeled MCF concentrations are in approximate equilibrium between the two hemispheres due to near perfect balance in surface emissions and chemical loss in each of the hemispheres. This mechanism helps to explain the temporal evolution in MCF concentration differences between the AGAGE measurement sites; e.g., from about 50 ppt difference in 1991 to none in 2006 between Mace Head and Cape Grim sites.

  18. Emissions of methyl chloroform inferred from a global atmospheric transport model

    NASA Astrophysics Data System (ADS)

    Taguchi, S.

    2003-04-01

    A global atmospheric transport model (NIRE-CTM-96) was used to investigate the relationship among the emission of methyl chloroform(MCF: McCulloch and Midgley, 2001), OH and the observed atmospheric concentration (ALE/ GAGE/ AGAGE, Prinn et al., 2000). The model has a 2.5x2.5 lat-long horizontal resolution, 15 vertical levels up to about 30 km, and a 6-hour integration time step. Inter-annual variation of atmospheric transport was taken into account by using meteorological data analyzed at European Centre for Medium Range Weather Forecasts(ECMWF) for the period 1979 to 1999. Time-dependent change in the geographical distribution of the MCF emission ( Midgley and McCulloch, 1995) was incorporated into model simulations by using the emission data at six geographical regions. Loss rate in the troposphere was estimated using temperature fields of the ECMWF dataset, monthly and zonal mean OH ( Spivakovsky et al., 2000) and the rate constant ( Talkudar et al.,1992). Simulated concentrations at the end of 1978 were consistent with the observations but those after 1979 were overestimated significantly. Simulated concentrations were consistent with the observations for the period 1979 to 1996 if OH was increased by 10% for the whole period. Global lifetime of the simulated MCF changed from 4.7 to 5.3 years during this simulation, indicating that the distribution of MCF itself in the atmosphere might contribute to the inter-annual variability of its global loss since OH does not distribute homogeneously. We estimated industrial MCF emission scenarios with the natural emissions from biomass burning (Lobert et al., 1999) for zero trend OH.

  19. Extracellular lipids of Camelina sativa: characterization of chloroform-extractable waxes from aerial and subterranean surfaces.

    PubMed

    Razeq, Fakhria M; Kosma, Dylan K; Rowland, Owen; Molina, Isabel

    2014-10-01

    Camelina sativa (L.) Crantz is an emerging low input, stress tolerant crop with seed oil composition suitable for biofuel and bioproduct production. The chemical compositions and ultrastructural features of surface waxes from C. sativa aerial cuticles, seeds, and roots were analyzed using gas chromatography and microscopy. Alkanes, primary fatty alcohols, and free fatty acids were common components of all analyzed organs. A particular feature of leaf waxes was the presence of alkyl esters of long-chain fatty acids and very long-chain fatty alcohols, ranging from C38 to C50 and dominated by C42, C44 and C46 homologues. Stem waxes were mainly composed of non-sterol pentacyclic triterpenes. Flowers accumulated significant amounts of methyl-branched iso-alkanes (C29 and C31 total carbon number) in addition to straight-chain alkanes. Seed waxes were mostly primary fatty alcohols of up to 32 carbons in length and unbranched C29 and C31 alkanes. The total amount of identified wax components extracted by rapid chloroform dipping of roots was 280μgg(-1) (fresh weight), and included alkyl hydroxycinnamates, predominantly alkyl coumarates and alkyl caffeates. This study provides qualitative and quantitative information on the waxes of C. sativa root, shoot, and seed boundary tissues, allowing the relative activities of wax biosynthetic pathways in each respective plant organ to be assessed. This detailed description of the protective surface waxes of C. sativa may provide insights into its drought-tolerant and pathogen-resistant properties, and also identifies C. sativa as a potential source of renewable high-value natural products. PMID:25081105

  20. Dose-response study of chloroform carcinogenesis in the mouse and rat: status report.

    PubMed Central

    Jorgenson, T A; Rushbrook, C J; Jones, D C

    1982-01-01

    Chloroform is being administered to male Osborne-Mendel rats and to female B6C3F1 mice at concentrations of 0 (negative control), 200, 400, 900 or 1800 ppm in the drinking water. Matched control groups of both species receive a volume of water identical to that consumed by the corresponding 1800 ppm groups. At this writing, the animals have completed 23 months on test. Negative control and CHCl3-treated rat groups have shown typical growth curves, with dose-related relative decrements in body weight evident throughout the study. Following decreases in CHCl3 groups during the first 8 weeks, rat water consumption values have continued to increase slowly, but persistent relative dose-related decrements are evident. No initial treatment-related decrements are evident. No initial treatment-related mortality was seen in the rats. Survival is 21, 41, 45, 76, 70 and 64% for the negative control, 200, 400, 900, 1800 ppm and matched control groups, respectively. Survival values for mice at three weeks were 99, 94, 74 and 76% for the 200, 400, 900 and 1800 ppm groups, respectively. Mortality was apparently related to markedly decreased fluid consumption among some of the treated mice. Subsequent mortality has been less than 15% for all mouse groups. Except for acclimation effects during the first 2-3 weeks, body weights for the treated mouse groups have been generally within 10% of negative control values. Tissue changes in decedents have been similar in treated and control groups, both in rats and mice. Terminal sacrifice and histologic evaluations will be initiated after completion of 24 months on test. PMID:7151755

  1. Product toxicity and cometabolic competitive inhibition modeling of chloroform and trichloroethylene transformation by methanotrophic resting cells.

    PubMed Central

    Alvarez-Cohen, L; McCarty, P L

    1991-01-01

    The rate and capacity for chloroform (CF) and trichloroethylene (TCE) transformation by a mixed methanotrophic culture of resting cells (no exogenous energy source) and formate-fed cells were measured. As reported previously for TCE, formate addition resulted in an increased CF transformation rate (0.35 day-1 for resting cells and 1.5 day-1 for formate-fed cells) and transformation capacity (0.0065 mg of CF per mg of cells for resting cells and 0.015 mg of CF per mg of cells for formate-fed cells), suggesting that depletion of energy stores affects transformation behavior. The observed finite transformation capacity, even with an exogenous energy source, suggests that toxicity was also a factor. CF transformation capacity was significantly lower than that for TCE, suggesting a greater toxicity from CF transformation. The toxicity of CF, TCE, and their transformation products to whole cells was evaluated by comparing the formate oxidation activity of acetylene-treated cells to that of non-acetylene-treated cells with and without prior exposure to CF or TCE. Acetylene arrests the activity of methane monooxygenase in CF and TCE oxidation without halting cell activity toward formate. Significantly diminished formate oxidation by cells exposed to either CR or TCE without acetylene compared with that with acetylene suggests that the solvents themselves were not toxic under the experimental conditions but their transformation products were. The concurrent transformation of CF and TCE by resting cells was measured, and results were compared with predictions from a competitive-inhibition cometabolic transformation model. The reasonable fit between model predictions and experimental observations was supportive of model assumptions. PMID:1905516

  2. Non-linear optics and local-field factors in liquid chloroform: A time-dependent density-functional theory study

    NASA Astrophysics Data System (ADS)

    Strubbe, David A.; Andrade, Xavier; Rubio, Angel; Louie, Steve G.

    2009-03-01

    Chloroform is often used as a solvent and reference when measuring non-linear optical properties of organic molecules. We calculate directly the non-linear susceptibilities of liquid chloroform at optical frequencies, using molecular dynamics and the Sternheimer equation in time-dependent density-functional theory [X. Andrade et al., J. Chem. Phys. 126, 184106 (2007)]. We compare the results to those of chloroform in the gas and solid phases, and experimental values, and make an ab initio calculation of the local-field factors which are needed to extract molecular properties from liquid calculations and experimental measurements.

  3. The Utilization of Chloroform Post-Treatment to Improve the Adhesion of Au Thin Films onto PMMA

    NASA Astrophysics Data System (ADS)

    Krist, Kathleen; Hughes, Chris; Hu, Xiaofeng; Augustine, Brian

    2015-03-01

    The metallization of Au onto plastics is an important processing step in the fabrication of microfluidic devices. While its corrosion resistance and excellent electrical and thermal conductivity make Au a good choice, its inertness results in poor adhesion to polymer surfaces. Previous studies have indicated that exposing commercially available Poly(methyl methacrylate) (PMMA) sheets to chloroform vapor following Au deposition significantly improves adhesion. In this study, we deposited 6 nm of Au onto 1.50 mm thick PMMA and exposed the samples to vapor released from chloroform heated on a hot plate set at 70 °C. The force required to remove the Au thin films was determined by placing samples on a polisher spinning at 150 rpm and utilizing UV-VIS spectroscopy to measure the transmittance of 700 nm light through the films to quantify their removal as a function of applied polishing force. The Au thin films were also characterized using AFM. AFM images demonstrated a progressive roughening of the surface corresponding to an increase in applied force. Additionally, these images support a model in which the chloroform treatment softens the PMMA surface, producing a softened layer that the polisher removes simultaneously with the Au thin film. Undergraduate.

  4. Survey on efficacy of chloroformic extract of Artemisia annua against Giardia lamblia trophozoite and cyst in vitro.

    PubMed

    Golami, Shirzad; Rahimi-Esboei, Bahman; Mousavi, Parisa; Marhaba, Zahra; Youssefi, Mohammad Reza; Rahimi, Mohammad Taghi

    2016-03-01

    Giardiasis is a parasitic cosmopolitan disease that the rate of infection in developing countries is considerable. This infection directly is associated with poor hygienic conditions, poor water quality control, and overcrowding. Reinfection and drug resistance are two major problems in endemic areas. Recently, researchers are concentrating on herbal drugs as a proper solution. Therefore, the objective of the present study was to survey on efficacy of chloroformic extract of Artemisia annua against Giardia lamblia trophozoite and cyst in vitro. G. lamblia cysts were prepared from faces of giardiasis patients from different hospitals of Mazandaran Medical University. Four concentrations (1, 10, 50 and 100 mg/ml) of chloroformic extract of A. annua were utilized for 1, 5, 30, 60 and 180 min. Viability of G. lamblia cysts was confirmed by 0.1 % Eosin staining. Cyst and trophozoite contact (intermix) of G. lamblia with extract of A. annua with variant concentrations (1, 10, 50 and 100 mg/ml) after 1 and 180 min caused following cyst and trophozoite elimination rates: (67, 69, 71 and 73 %), (65, 67, 67 and 72 %), (94, 96, 97 and 99 %) and (100, 100, 100 and 100 %), respectively. Authors from the current investigation draw a conclusion that chloroformic extract of A. annua has the ability to eliminate G. lamblia cysts and trophozoites in vitro. PMID:27065604

  5. A novel photoproduct of 2'-deoxyguanosine induced by acetone photosensitization: 8-(2,3,4-trihydroxybutyl)guanine.

    PubMed Central

    Sharma, N D; Davies, R J; Phillips, D R; McCloskey, J A

    1989-01-01

    Acetone photosensitisation of 2'-deoxyguanosine in deaerated aqueous solution gives 8-(2,3,4-trihydroxybutyl)guanine as a major photoproduct. Its structure and that of its tetraacetate have been determined primarily by high resolution 1H NMR and mass spectrometry; a di-isopropylidene derivative has also been prepared. Mechanistic aspects of this novel photochemical transformation are discussed, particularly in relation to the alkaline cleavage of acetone photosensitised DNA at the sites of guanine bases. PMID:2922279

  6. Simultaneous quantitative Acetone-PLIF measurements for determination of temperature and gas composition fields in an IC-engine

    NASA Astrophysics Data System (ADS)

    Trost, Johannes; Löffler, Micha; Zigan, Lars; Leipertz, Alfred

    Acetone-PLIF is a preferable technique to measure temperature and exhaust gas distribution simultaneously in an optical accessible internal combustion engines with exhaust gas recirculation. In this work calibration data of the fluorescence signal intensity of acetone for excitation wavelengths of 248 nm and 308 nm is given for gasoline engine relevant conditions. An examplary application on a fired transparent Direct Injection Spark Ignition (DISI) engine is presented to clarify the accuracy of the calibration data.

  7. Ethyl Lithiodiazoacetate: Extremely Unstable Intermediate Handled Efficiently in Flow.

    PubMed

    Müller, Simon T R; Hokamp, Tobias; Ehrmann, Svenja; Hellier, Paul; Wirth, Thomas

    2016-08-16

    Ethyl diazoacetate (EDA) is one of the most prominent diazo reagents. It is frequently used in metal-carbene-type reactions. However, EDA can also be used as a nucleophile under base catalysis. Whilst the addition of EDA to aldehydes can be performed using organic bases, the addition of EDA to other carbonyl electrophiles requires the use of organometallics such as lithium diisopropylamide (LDA). The generated ethyl lithiodiazoacetate is highly reactive and decomposes rapidly, even at low temperatures. Herein, we report a continuous flow protocol that overcomes the problems associated with the instantaneous decomposition of ethyl lithiodiazoacetate. The addition of ethyl lithiodiazoacetate to ketones provides direct access to tertiary diazoalcohols in good yields. PMID:27339757

  8. [Reaction of 1,8-naphthyridine azides with ethyl acrylate].

    PubMed

    Livi, O; Ferrarini, P L; Bertini, D; Tonetti, I

    1975-12-01

    The reaction of 1,8-naphthyridine azides with ethyl acrylate leads to the formation of 2-pyrazolines instead of 1,2,3-triazolines. Some of the compounds obtained have undergone pharmacological and microbiological (antibacterial) testing. PMID:1204828

  9. Suppression of Pulmonary Host Defenses and Enhanced Susceptibility to Respiratory bacterial Infection in mice Following Inhalation Exposure to Trichloroethylene and Chloroform

    EPA Science Inventory

    Numerous epidemiologic studies have associated episodes of increased air pollution with increased incidence of respiratory disease, including pneumonia, croup, and bronchitis. Trichloroethylene (TCE) and chloroform are among 33 hazardous air pollutants identified by the U.S. Env...

  10. SYNTHESIS OF HIGHLY FLUORINATED CHLOROFORMATES AND THEIR USE AS DERIVATIZING AGENTS FOR HYDROPHILIC COMPOUNDS AND DRINKING WATER DISINFECTION BY-PRODUCTS

    EPA Science Inventory

    A rapid, safe and efficient procedure was developed to synthesize perfluorinated chloroformates in the small scale generally required to perform analytical derivatizations. This new family of derivatizing agents allows straightforward derivatization of highly polar compounds, co...

  11. Interaction of Trace gas Species of Atmospheric Interest With ice: Measurement of the Adsorption Enthalpy of Acetone on ice

    NASA Astrophysics Data System (ADS)

    Bartels-Rausch, T.; Guimbaud, C.; Gaggeler, H.; Ammann, M.

    2002-12-01

    Ice provides an important substrate for heterogeneous chemistry in the stratosphere, the upper troposphere, but also in the cold regions of the planetary boundary layer. Thus, we started to investigate the interaction of trace gases of atmospheric interest (acetone) with ice. In the upper troposphere, the photolysis of acetone is the main source of HOX, dominating the one from the reaction of O(1D) + H2O (Jaegle et al., 2001). Source and sinks of acetone need to be quantified to simulate the concentration of the main atmospheric oxidant (HOX). Ice cirrus clouds are suggested to be one of the acetone sinks. Thus, the adsorption enthalpy of acetone on ice needs to be investigated because it determines the mixing ratio of acetone between the gas and the particulate phase and the chemistry of the upper troposphere. In this paper, the chromatographic method applied for the measurement of the adsorption enthalpy of acetone on ice is described. This method uses a chromatographic ice-packed column similar to the one described by Bartels et al. (2002) and is combined with Proton Transfer Reaction Mass Spectrometry (PTR-MS) for the monitoring of the acetone concentration in the gas phase. Preliminary results show that the measured standard adsorption enthalpy obtained with a column packed with ice spheres, i.e. (-54+/-8) kJ mol-1, and with a column packed with a snow sample, i.e. (-56+/-3) kJ mol-1, are similar and in agreement with the ones derived by Winkler et al. (2002) and from Domine and Hanot (2002), using a low pressure ice coated wall flow tube reactor and a volumetric method, respectively. More investigations are scheduled in the near future using different ice surfaces (ice crystals, fresh snow). We briefly address the atmospheric implication of this study as well as the perspective of the chromatographic & APCI-MS system to investigate other processes of atmospheric interest. References Bartels, T., B. Eichler, P. Zimmermann, H. W. Gäggeler, and M. Ammann, The

  12. Interpretation of PAN, acetone and acetylene measurements from the MIPAS-E

    NASA Astrophysics Data System (ADS)

    Moore, D. P.; Remedios, J. J.; Parker, R. J.

    2009-04-01

    Emissions of anthropogenic pollution, from biomass burning events in particular, result in the injection of a wide range of carbon compounds into the atmosphere. Carbon monoxide (CO), methane (CH4) and volatile organic compounds (VOCs) are released in significant amounts, affecting both the oxidation capacity of the troposphere and ozone production. Upper troposphere (UT) measurements of PAN, acetone and acetylene have, in the past, been generally limited to sporadic in situ sampling during specialised campaign periods. The recent rapid progress in both the detection and retrieval of many VOC species from spaceborne instrumentation has been large. It has recently been established that the observation of the global distribution of VOCs in the UT can be made by measurements provided by instruments such as the Michelson Interferometer for Passive Atmospheric Sounding onboard ENVISAT (MIPAS-E) or the Atmospheric Chemistry Experiment (ACE) onboard SCISAT-1. In this work, we discuss the ability of MIPAS-E to provide new global measurements of acetone in the UT. We also describe both the distribution and seasonality observed in UT PAN volume mixing ratios (vmrs). From the MIPAS-E acetylene measurements, we analyse the extent and magnitude of the chemical isolation observed over the Middle East during August 2003. We show that this enhancement is due to fast westward transport from Asia via the Easterly Jet associated with the Asian monsoon anticyclone. A full error analysis is carried out for each of the three gases we analyse. Previous work has shown that characteristic infrared signatures of PAN, acetone and acetylene can be detected in MIPAS-E thermal emission spectra, with the 787-790 cm-1, 1216-1218 cm-1 and 776.0-776.15 cm-1 spectral ranges respectively being particularly sensitive to changes in each of the gases. We invert the measured MIPAS-E spectra into vmrs using an independent offline-retrieval scheme based on the optimal estimation approach which was

  13. Diagnosis of chronic alcohol consumption. Hair analysis for ethyl-glucuronide.

    PubMed

    Jurado, C; Soriano, T; Giménez, M P; Menéndez, M

    2004-10-29

    This paper describes a procedure for the detection and quantification of ethyl-glucuronide (EtG) in hair samples. During method development the efficacy of extraction of EtG from hair was compared in four extraction methods: (a) methanol; (b) methanol:water (1:1); (c) water; and (d) water:trifluoroacetic acid (9:1). In addition, three derivatizing agents were compared as well: N,O-bistrimethylsilyl-trifluoroacetamide (BSTFA): trimethylchlorosilane (TMCS) (99:1), pentafluoropropionic anhydride (PFPA) and heptafluorobutyric anhydride (HFBA). Water was found to be the best extracting solvent and PFPA the best derivatizing agent. Both provided the highest recoveries, with cleaner extracts and more stable derivatives. The final method is as follows: about 100mg of hair are sequentially washed with water and acetone. The decontaminated sample is finely cut with scissors, then the deuterated internal standard (EtG-d5) and 2 mL of water are added. After sonication for 2 h, the sample is maintained at room temperature overnight. Derivatization is performed with PFPA. Derivatives are injected into a GC-MS system in the electronic impact mode. The method shows linearity over the range of concentrations from 0.050 to 5 ng/mg. Detection and quantification limits are 0.025 and 0.050 ng/mg, respectively. Mean recoveries for the three studied concentrations (low, medium and high) are higher than 87%. The coefficients of variation in intra- and inter-assay precision are always lower than 7%. The method is being routinely applied in our lab for the diagnosis of chronic alcohol consumption. PMID:15451088

  14. Study of intermolecular interaction of allyl chloride with acetone through dielectric and volumetric properties

    NASA Astrophysics Data System (ADS)

    Sudake, Y. S.; Kamble, S. P.; Maharolkar, A. P.; Patil, S. S.; Khirade, P. W.

    2012-06-01

    The static dielectric constant (ɛs)and relaxation time (τ) are determined from complex permittivity spectra of Allyl Chloride (ALC) with Acetone (ACE), which are obtained using the Time Domain Reflectometry (TDR) technique in microwave frequency range 10 MHz to 10 GHz. Density (ρ) and refractive index (nD) were also measured. These parameters are used to determine excess dielectric constant, excess molar volume, and excess molar refraction. The excess parameter is fitted to Redlich-Kister(RK) equation. The values of excess parameters are positive in ALC rich region whereas in ACE rich region are negative.

  15. Density Functional Studies on the Complexation and Spectroscopy of Uranyl Ligated with Acetonitrile and Acetone Derivatives

    SciTech Connect

    Schoendorff, George E.; Windus, Theresa L.; De Jong, Wibe A.

    2009-12-12

    The coordination of nitrile (acetonitrile, propionitrile, and benzonitrile) and carbonyl (formaldehyde, ethanal, and acetone) ligands to the uranyl dication (UO22+) has been examined using density functional theory (DFT) utilizing relativistic effective core potentials (RECPs). Complexes containing up to six ligands have been modeled for all ligands except formaldehyde, for which no minimum could be found. A comparison of relative binding energies indicates that five coordinate complexes are predominant while a six coordinate complex involving propionitrile ligands might be possible. Additionally, the relative binding energy and the weakening of the uranyl bond is related to the size of the ligand and, in general, nitriles bind more strongly to uranyl than carbonyls.

  16. Bioreactors and in situ product recovery techniques for acetone-butanol-ethanol fermentation.

    PubMed

    Li, Si-Yu; Chiang, Chung-Jen; Tseng, I-Ting; He, Chi-Ruei; Chao, Yun-Peng

    2016-07-01

    The microbial fermentation process is one of the sustainable and environment-friendly ways to produce 1-butanol and other bio-based chemicals. The success of the fermentation process greatly relies on the choice of bioreactors and the separation methods. In this review, the history and the performance of bioreactors for the acetone-butanol-ethanol (ABE) fermentation is discussed. The subject is then focused on in situ product recovery (ISPR) techniques, particularly for the integrated extraction-gas stripping. The usefulness of this promising hybrid ISPR device is acknowledged by its incorporation with batch, fed-batch and continuous processes to improve the performance of ABE fermentation. PMID:27190167

  17. Sensitive gas chromatographic detection of acetaldehyde and acetone using a reduction gas detector

    NASA Technical Reports Server (NTRS)

    O'Hara, Dean; Singh, Hanwant B.

    1988-01-01

    The response of a newly available mercuric oxide Reduction Gas Detector (RGD-2) to subpicomole and larger quantities of acetaldehyde and acetone is tested. The RGD-2 is found to be capable of subpicomole detection for these carbonyls and is more sensitive than an FID (Flame Ionization Detector) by an order of magnitude. Operating parameters can be further optimized to make the RGD-2 some 20-40 times more sensitive than an FID. The detector is linear over a wide range and is easily adapted to a conventional gas chromatograph (GC). Such a GC-RGD-2 system should be suitable for atmospheric carbonyl measurements in clean as well as polluted environments.

  18. Pervaporation of model acetone-butanol-ethanol fermentation product solutions using polytetrafluoroethylene membranes

    SciTech Connect

    Vrana, D.L.; Meagher, M.M.; Hutkins, R.W.; Duffield, B. )

    1993-10-01

    A pervaporation apparatus was designed and tested in an effort to develop an integrated fermentation and product recovery process for acetone-butanol-ethanol(ABE) fermentation. A crossflow membrane module able to accommodate flat sheet hydrophobic membranes was used for the experiments. Permeate vapors were collected under vacuum and condensed in a dry ice/ethanol cold trap. The apparatus containing polytetrafluoroethylene membranes was tested using butanol-water and model solutions of ABE products. Parameters such as product concentration, component effect, temperature, and permeate side pressure were examined. 25 refs., 3 figs., 5 tabs.

  19. Marking planes of surgical excision on breast biopsy specimens: use of artists' pigments suspended in acetone.

    PubMed Central

    Paterson, D A; Davies, J D

    1988-01-01

    The performance of carbon and metallic inks, silver nitrate solution, and artists' pigments mounted in acetone was compared for marking the surface of surgical biopsy specimens. Using India ink is an unsatisfactory procedure because of slow drying, messiness, and spreading of the ink. It is concluded that use of artists' pigments has many advantages over other reagents, because of their rapid drying, resistance to tissue processing, and the ability to mark simultaneously many different planes of excision. Furthermore, the pigments are readily visible, are distinguishable from each other on microscopical examination, and the method entails little extra cost. Images Fig 1 Fig 2 PMID:3056982

  20. Regulation of acetone butanol production in batch and continuous cultures of Clostridium acetobutylicum

    SciTech Connect

    Monot, F.; Engasser, J.M.; Petitdemange, H.

    1983-01-01

    The influence of pH and glucose concentration in batch and continuous cultures of Clostridium acetobutylicum is examined. At high pH and low glucose concentration only acids are produced. At low pH and high initial or feed glucose concentration, butanol and acetone are the main metabolites produced. According to a detailed kinetic analysis of the different fermentations, solvents are only produced if the concentration of undissociated butyric acid in the medium reaches a critical level. 10 references, 9 figures, 1 table.

  1. The targets of acetone cyanohydrin neurotoxicity in the rat are not the ones expected in an animal model of konzo.

    PubMed

    Soler-Martín, Carla; Riera, Judith; Seoane, Ana; Cutillas, Blanca; Ambrosio, Santiago; Boadas-Vaello, Pere; Llorens, Jordi

    2010-01-01

    Konzo is a neurotoxic motor disease caused by excess consumption of insufficiently processed cassava. Cassava contains the cyanogenic glucoside linamarin, but konzo does not present the known pathological effects of cyanide. We hypothesized that the aglycone of linamarin, acetone cyanohydrin, may be the cause of konzo. This nitrile rapidly decomposes into cyanide and acetone, but the particular exposure and nutrition conditions involved in the emergence of konzo may favor its stabilization and subsequent acute neurotoxicity. A number of preliminary observations were used to design an experiment to test this hypothesis. In the experiment, young female Long-Evans rats were given 10mM acetone cyanohydrin in drinking water for 2 weeks, and then 20mM for 6 weeks. Nutrition deficits associated with konzo were modeled by providing tapioca (cassava starch) as food for the last 3 of these weeks. After this period, rats were fasted for 24h in order to increase endogenous acetone synthesis, and then exposed to 0 (control group) or 50 micromol/kg-h of acetone cyanohydrin for 24h (treated group) through subcutaneous osmotic minipump infusion (n=6/group). Motor activity and gait were evaluated before exposure (pre-test), and 1 and 6 days after exposure. Brains (n=4) were stained for neuronal degeneration by fluoro-jade B. Rats exposed to 50 micromol/kg-h of acetone cyanohydrin showed acute signs of toxicity, but no persistent motor deficits. Two animals showed fluoro-jade staining in discrete thalamic nuclei, including the paraventricular and the ventral reuniens nuclei; one also exhibited labeling of the dorsal endopiriform nucleus. Similar effects were not elicited by equimolar KCN exposure. Therefore, acetone cyanohydrin may cause selective neuronal degeneration in the rat, but the affected areas are not those expected in an animal model of konzo. PMID:19932169

  2. Industrial production of acetone and butanol by fermentation-100 years later.

    PubMed

    Sauer, Michael

    2016-07-01

    Microbial production of acetone and butanol was one of the first large-scale industrial fermentation processes of global importance. During the first part of the 20th century, it was indeed the second largest fermentation process, superseded in importance only by the ethanol fermentation. After a rapid decline after the 1950s, acetone-butanol-ethanol (ABE) fermentation has recently gained renewed interest in the context of biorefinery approaches for the production of fuels and chemicals from renewable resources. The availability of new methods and knowledge opens many new doors for industrial microbiology, and a comprehensive view on this process is worthwhile due to the new interest. This thematic issue of FEMS Microbiology Letters, dedicated to the 100th anniversary of the first industrial exploitation of Chaim Weizmann's ABE fermentation process, covers the main aspects of old and new developments, thereby outlining a model development in biotechnology. All major aspects of industrial microbiology are exemplified by this single process. This includes new technologies, such as the latest developments in metabolic engineering, the exploitation of biodiversity and discoveries of new regulatory systems such as for microbial stress tolerance, as well as technological aspects, such as bio- and down-stream processing. PMID:27199350

  3. Revisiting aqueous-acetone mixtures through the concept of molecular emulsions

    NASA Astrophysics Data System (ADS)

    Kežić, Bernarda; Perera, Aurélien

    2012-10-01

    Aqueous acetone mixtures represent a good example of perfectly miscible liquids in reality, and that hard to mix in silico. This is related to a key problem in molecular simulations, which is to distinguish between strongly micro-segregated mixtures from phase-separated ones. The Kirkwood-Buff integrals of in silico aqueous mixtures are often found to be dramatically higher than the experimental ones, hinting at a possible underlying phase separation. This is the case for many combinations of the force field models chosen for water or for acetone. Herein, we demonstrate, through a proper handling of the tail of the correlation functions, that these high values of the Kirkwood-Buff integrals represent in fact a transient regime within the segregated spatial domains, and that they asymptotically settle down to values in much better agreement with the experimental ones. The concept central to this new approach is that of molecular emulsions, where the long range part of the correlations is modulated by the micro-segregated domains, and that it is necessary to take into this modulation in order to recover the correct thermodynamical properties.

  4. Industrial production of acetone and butanol by fermentation—100 years later

    PubMed Central

    Sauer, Michael

    2016-01-01

    Microbial production of acetone and butanol was one of the first large-scale industrial fermentation processes of global importance. During the first part of the 20th century, it was indeed the second largest fermentation process, superseded in importance only by the ethanol fermentation. After a rapid decline after the 1950s, acetone-butanol-ethanol (ABE) fermentation has recently gained renewed interest in the context of biorefinery approaches for the production of fuels and chemicals from renewable resources. The availability of new methods and knowledge opens many new doors for industrial microbiology, and a comprehensive view on this process is worthwhile due to the new interest. This thematic issue of FEMS Microbiology Letters, dedicated to the 100th anniversary of the first industrial exploitation of Chaim Weizmann's ABE fermentation process, covers the main aspects of old and new developments, thereby outlining a model development in biotechnology. All major aspects of industrial microbiology are exemplified by this single process. This includes new technologies, such as the latest developments in metabolic engineering, the exploitation of biodiversity and discoveries of new regulatory systems such as for microbial stress tolerance, as well as technological aspects, such as bio- and down-stream processing. PMID:27199350

  5. Enzymology of acetone-butanol-isopropanol formation. Progress report, January 1, 1991--December 31, 1991

    SciTech Connect

    Chen, Jiann-Shin

    1992-01-01

    The long-term goal of the project is to understand the fundamental properties of biological solvent production. Our approach is to elucidate first the molecular properties of solvent-producing enzymes and then to apply to information gained from the enzymological study to investigate control mechanisms for the solvent-producing pathways and the expression of solvent-production genes. Our research primarily involves two strains of Clostridium beijerinckii: C. Beijerinckii NRRL B593 which produces isopropanol in addition to acetone, butanol, and ethanol, and C. beijerinckii NRRL B592 which produces acetone, butanol and ethanol, but not isopropanol. In more recent studies, we also included another solvent-producing organism, Bacillus macerans. Objectives for the reporting period were: to characterize the distinct types of alcohol dehydrogenase; to purify and characterize acetoacetyl-CoA-reacting enzymes; and to clone and sequence the gene encoding the primary/secondary alcohol dehydrogenase of C beijerinckii NRRL B593 and to search for the promoter region for solvent-production genes.

  6. Microwave Spectra and AB Initio Studies of the Ne-Acetone Complex

    NASA Astrophysics Data System (ADS)

    Gao, Jiao; Thomas, Javix; Xu, Yunjie; Jäger, Wolfgang

    2015-06-01

    Microwave spectra of the neon-acetone van der Waals complex were measured using a cavity-based molecular beam Fourier-transform microwave spectrometer in the region from 5 to 18 GHz. Both 20Ne and 22Ne containing isotopologues were studied and both c- and weaker a-type rotational transitions were observed. The transitions are split into multiplets due to the internal rotation of two methyl groups in acetone. Electronic structure calculations were done at the MP2 level of theory with the 6-311++g (2d, p) basis set for all atoms and the internal rotation barrier height of the methyl groups was determined to be about 2.8 kJ/mol. The ab initio rotational constants were the basis for our spectroscopic searches, but the multiplet structures and floppiness of the complex made the quantum number assignment very difficult. The assignment was finally achieved with the aid of constructing closed frequency loops and predicting internal rotation splittings using the XIAM code. Analyses of the spectra yielded rotational and centrifugal distortion constants, as well as internal rotation parameters, which were interpreted in terms of structure and internal dynamics of the complex. H. Hartwig and H. Dreizler, Z. Naturforsch. A 51, 923 (1996).

  7. Acetone Extract of Almond Hulls Provides Protection against Oxidative Damage and Membrane Protein Degradation.

    PubMed

    Meshkini, Azadeh

    2016-06-01

    Several studies have revealed that among foods, the consumption of edible nuts has beneficial effects on health which are attributed to their high content of potent antioxidants. Among nuts, the whole seed of the almond (Prunus dulcis) has been demonstrated to possess potent free radical scavenging activity, which is related to the presence of phenolic compounds. The aim of the current study is to evaluate the polyphenol content and the antioxidant ability of almond hull, which is an agriculture solid waste. The present results revealed that among different extraction methods, the acetone extract of almond hulls has a high content of phenolic and flavonoid compounds and a high antioxidant ability, which were determined by using the phosphomolybdenum method and by measuring the potency of the antioxidant, respectively. Moreover, the experimental data disclosed that the acetone extract of almond hulls provides protection against the oxidative damage and the membrane protein degradation that are caused in human erythrocytes by hydrogen peroxide. These phenomena may likely be due to the recruitment of antioxidants by cell membranes and/or translocation to cytosol. Overall, almond hull extract could be considered as a natural source of antioxidants, and its consumption could have a positive effect on human health. PMID:27342887

  8. High temperature catalytic hydrogenation of acetone over Raney Ni for chemical heat pump

    NASA Astrophysics Data System (ADS)

    Duan, Yanjun; Xu, Min; Huai, Xiulan

    2014-02-01

    Exothermic hydrogenation reaction of acetone is an important part of an IAH-CHP, and the performance of IAH-CHP is affected directly by this reaction. This paper studies the influence of space velocity, temperature, hydrogen flow rate and pressure on conversion and selectivity experimentally. The byproducts are analyzed and classified into three types: hydrogenation product, cracking products and condensation products. Both the conversion and selectivity of this reaction have the same trend with the change of space velocity, temperature and hydrogen flow rate, and has the opposite trend with the change of pressure. As the space velocity increases, the conversion curve is a gradual decline parabola but the selectivity curve is close to a straight line. Hydrogen flow rate has a more obvious influence on conversion than temperature, whereas on selectivity the situation is opposite. High pressure increases the conversion of acetone to all products, but the increment of byproducts is more than that of isopropanol, so the selectivity decreases as pressure increases.

  9. Secondary alcohol dehydrogenase catalyzes the reduction of exogenous acetone to 2-propanol in Trichomonas vaginalis.

    PubMed

    Sutak, Robert; Hrdy, Ivan; Dolezal, Pavel; Cabala, Radomir; Sedinová, Miroslava; Lewin, Joern; Harant, Karel; Müller, Miklos; Tachezy, Jan

    2012-08-01

    Secondary alcohols such as 2-propanol are readily produced by various anaerobic bacteria that possess secondary alcohol dehydrogenase (S-ADH), although production of 2-propanol is rare in eukaryotes. Specific bacterial-type S-ADH has been identified in a few unicellular eukaryotes, but its function is not known and the production of secondary alcohols has not been studied. We purified and characterized S-ADH from the human pathogen Trichomonas vaginalis. The kinetic properties and thermostability of T. vaginalis S-ADH were comparable with bacterial orthologues. The substantial activity of S-ADH in the parasite's cytosol was surprising, because only low amounts of ethanol and trace amounts of secondary alcohols were detected as metabolic end products. However, S-ADH provided the parasite with a high capacity to scavenge and reduce external acetone to 2-propanol. To maintain redox balance, the demand for reducing power to metabolize external acetone was compensated for by decreased cytosolic reduction of pyruvate to lactate and by hydrogenosomal metabolism of pyruvate. We speculate that hydrogen might be utilized to maintain cytosolic reducing power. The high activity of Tv-S-ADH together with the ability of T. vaginalis to modulate the metabolic fluxes indicate efficacious metabolic responsiveness that could be advantageous for rapid adaptation of the parasite to changes in the host environment. PMID:22686835

  10. [Toluene, Benzene and Acetone Adsorption by Activated Carbon Coated with PDMS].

    PubMed

    Liu, Han-bing; Jiang, Xin; Wang, Xin; Yang, Bing; Xue, Nan-dong; Zhang, Shi-lei

    2016-04-15

    To improve the adsorption selectivity of volatile organic compounds ( VOCs) , activated carbon ( AC) was modified by polydimethylsiloxane (PDMS) and characterized by BET analysis and Boehm titration. Dynamic adsorption column experiments were conducted and Yoon-Neslon(Y-N) model was used to identify adsorption effect for toluene, beuzene and acetone on AC when relative humidity was 0%, 50% and 90%, respectively. The results showed that the BET area, micropore volume and surface functional groups decreased with the PDMS modification, and surface hydrophobicity of the modified AC was enhanced leading to a lower water adsorption capacity. The results of dynamic adsorption showed that the adsorption kinetics and capacity of Bare-AC decreased with the increase of relative humidity, and the adsorption capacities of PDMS coated AC were 1.86 times (toluene) and 1.92 times (benzene) higher than those of Bare-AC, while a significant improvement of adsorption capacity for acetone was not observed. These findings suggest that polarity of molecule can be an important influencing factor for adsorption on hydrophobic surface developed by PDMS. PMID:27548948

  11. Acetone cataluminescence as an indicator for evaluation of heterogeneous base catalysts in biodiesel production.

    PubMed

    Zhang, Lijuan; Chen, Yingchun; He, Nan; Lu, Chao

    2014-01-01

    Rapid and effective evaluation techniques for heterogeneous base catalysts in biodiesel production are highly desirable with increased global demand for biofuels. In this work, we have discovered direct connections between the number of medium-strength basic sites of heterogeneous base catalysts in biodiesel production and cataluminescence intensity in acetone aldol condensation reactions. Accordingly, acetone cataluminescence has been employed as an indicator for rapid evaluation of heterogeneous base catalysts in biodiesel production. Its practical feasibility has been first established using commercially available heterogeneous base catalysts in biodiesel production (including MgO, Al2O3, TiO2, and ZnO), indicating a good matching between the proposed cataluminescence screening method and routine temperature-programmed desorption measurements. Subsequently, the proposed cataluminescence method can be used to effectively distinguish a set of layered double hydroxides and layered double oxide with fewer differences of basic sites, and the relative standard deviation (RSD) of the proposed method is 2.90%. The developed cataluminescence platform is able to take advantage of low cost, simple configuration, fast response, long-term stability, and easy operation. This work has a great potential in distinguishing weak/strong basic sites and even acidic sites of each catalyst system by tuning molecular probes. PMID:24325398

  12. Biofiltration of a mixture of ethylene, ammonia, n-butanol, and acetone gases.

    PubMed

    Lee, Sang-Hun; Li, Congna; Heber, Albert J; Ni, Jiqin; Huang, Hong

    2013-01-01

    This study describes cleaning of a waste gas stream using bench scale biofilters (BFs) or biotrickling filters (BTFs). The gas stream contained a mixture of acetone, n-butanol, methane, ethylene, and ammonia, and was diverted uniformly to six biofilters and four biotrickling filters. The biofilters were packed with either perlite (BF-P), polyurethane foam (BF-F), or a mixture of compost, wood chips, and straw (BF-C), whereas the biotrickling filters contained either perlite (BTF-P) or polyurethane foam (BTF-F). Experimental results showed that both BFs and BTFs packed with various media were able to achieve complete removal of highly soluble compounds such as acetone, n-butanol, and ammonia of which the dimensionless Henry's constants (H) are less than 0.01. Methane was not removed due to its extreme insolubility (H>30). However, the ethylene (H ≈ 9) removal efficiencies depended on trickle water flow rates, media surface areas, and ammonia gas levels. PMID:23138059

  13. Interfacial Surgery Determination of Succinonitrile and Succinonitrile-Acetone Alloy Using Surface Light Scattering Spectrometer

    NASA Technical Reports Server (NTRS)

    Tin, Padetha; Frate, David T.; deGroh, Henry C., III

    2001-01-01

    The objectives of this ground based research is to measure the liquid/vapor interfacial surface energies of succinonitrile (SCN) and alloys of succinonitrile and acetone using Surface Light Scattering Spectrometer. Liquid/vapor interfacial energy measurements will be made near and above the melting point and are the primary goal of this proposal. A measurement of viscosity also results from the Surface Light Scattering technique employed. Interfacial free energies between the phases enters into many analysis of phase transformation and flow, including nucleation, dendritic growth, interface stability, Ostwald ripening, and Marangoni flow. Succirionitrile (SCN) is useful as a model for the study of metal solidification, although it is an organic material, it has a BCC crystal structure and solidifies dendriticly like a metal. It is also transparent and has a low melting point (58.08 C). Succinonitrile has been and is being used extensively in NASAs Microgravity Materials Science and Fluid Physics programs and as well as in several ground-based and microgravity studies including the Isothermal Dendritic Growth Experiment (IDGE) due to Glicksman and coworkers and subsequently in several theoretical and numerical studies of dendritic growth. Previous measurements of succinonitrile (SCN) and alloys of succinonitrile and acetone surface tensions are extremely limited. We believe the data sought through this proposal have significant basic physical property data value and thus the work proposed will provide needed data in support of NASAs Microgravity program research.

  14. Roles of acetone and diacetone alcohol in coordination and dissociation reactions of uranyl complexes.

    PubMed

    Rios, Daniel; Schoendorff, George; Van Stipdonk, Michael J; Gordon, Mark S; Windus, Theresa L; Gibson, John K; de Jong, Wibe A

    2012-12-01

    Combined collision-induced dissociation mass spectrometry experiments with DFT and MP2 calculations were employed to elucidate the molecular structures and energetics of dissociation reactions of uranyl species containing acetone and diacetone alcohol ligands. It is shown that solutions containing diacetone alcohol ligands can produce species with more than five oxygen atoms available for coordination. Calculations confirm that complexes with up to four diacetone alcohol ligands can be energetically stable but that the effective number of atoms coordinating with uranium in the equatorial plane does not exceed five. Water elimination reactions of diacetone alcohol ligands are shown to have two coordination-dependent reaction channels, through formation of mesityl oxide ligands or formation of alkoxide and protonated mesityl oxide species. The present results provide an explanation for the implausible observation of "[UO(2)(ACO)(6,7,8)](2+)" in and observed water-elimination reactions from purportedly uranyl-acetone complexes (Rios, D.; Rutkowski, P. X.; Van Stipdonk, M. J.; Gibson, J. K. Inorg. Chem. 2011, 50, 4781). PMID:23146003

  15. [Formation of ethyl carbamate in umeshu (plum liqueur)].

    PubMed

    Suzuki, K; Kamimura, H; Ibe, A; Tabata, S; Yasuda, K; Nishijima, M

    2001-12-01

    Samples of umeshu, a Japanese plum liqueur made from unripe plums, shochu and crystal sugar, were stored under fluorescent light, in the dark and in the refrigerator. The amount of ethyl carbamate formed in umeshu exposed to light or room temperature was larger than that in the dark or at low temperature. The amount of ethyl carbamate formed in umeshu to which cyanide had been added was larger than that in the absence of added cyanide. Thus, the amount of ethyl carbamate formed in the umeshu was increased by not only light and higher temperature, but also cyanide. Samples of model alcoholic beverages were stored under various conditions using red, yellow and blue cellophanes. The amount of ethyl carbamate formed in the model alcoholic beverage with blue cellophane was larger than in the cases of red and yellow cellophanes. It was found that the amount of ethyl carbamate formed in the model alcoholic beverage was increased by light in the wavelength range of 375-475 nm. PMID:11875819

  16. An acetone breath analyzer using cavity ringdown spectroscopy: an initial test with human subjects under various situations

    NASA Astrophysics Data System (ADS)

    Wang, Chuji; Surampudi, Anand B.

    2008-10-01

    We have developed a portable breath acetone analyzer using cavity ringdown spectroscopy (CRDS). The instrument was initially tested by measuring the absorbance of breath gases at a single wavelength (266 nm) from 32 human subjects under various conditions. A background subtraction method, implemented to obtain absorbance differences, from which an upper limit of breath acetone concentration was obtained, is described. The upper limits of breath acetone concentration in the four Type 1 diabetes (T1D) subjects, tested after a 14 h overnight fast, range from 0.80 to 3.97 parts per million by volume (ppmv), higher than the mean acetone concentration (0.49 ppmv) in non-diabetic healthy breath reported in the literature. The preliminary results show that the instrument can tell distinctive differences between the breath from individuals who are healthy and those with T1D. On-line monitoring of breath gases in healthy people post-exercise, post-meals and post-alcohol-consumption was also conducted. This exploratory study demonstrates the first CRDS-based acetone breath analyzer and its potential application for point-of-care, non-invasive, diabetic monitoring.

  17. Evaluation of the Acetone and Aqueous Extracts of Mature Stem Bark of Sclerocarya birrea for Antioxidant and Antimicrobial Properties

    PubMed Central

    Tanih, Nicoline F.; Ndip, Roland N.

    2012-01-01

    We assayed the antimicrobial activity of acetone and aqueous extracts of the stem bark of Sclerocarya birrea on some selected bacteria and fungi species including; Streptococcus pyogenes, Plesiomonas shigelloides, Aeromonas hydrophila, Salmonella typhimurium, Cryptococcus neoformans, Candida glabrata, Trichosporon mucoides, and Candida krusei using both agar well diffusion and minimum inhibitory concentration (MIC) assays. Based on the levels of activity, the acetone extract was examined for total polyphenolic content, radical scavenging and antioxidant activities. Total phenols of the extract were determined spectrophotometrically. The antioxidant activity was determined by the DPPH, ABTS and reducing power. All the bacteria and fungi species were susceptible to the plant extracts. The acetone extract was the most active for the bacterial species with MIC (0.156–0.625 mg/mL) while the aqueous extract was the most active for the fungi species with MIC (0.3125–1.25 mg/mL). The polyphenolic compounds were found as 27.2 mg/g tannic acid equivalent, 25.2 mg/g quercetin equivalent, 9.1 mg/g quercetin equivalent for phenols, flavonoid and flavonols respectively. The acetone extract exhibited a remarkable ability to scavenge radicals, strong reducing ability and a potential source of natural antioxidants. Both the acetone and aqueous extracts of S. birrea may provide a target for drug discovery. PMID:22675390

  18. Fate of acetone in an outdoor model stream with a nitrate supplement, southern Mississippi, U.S.A.

    USGS Publications Warehouse

    Rathbun, R.E.; Stephens, D.W.; Tai, D.Y.

    1991-01-01

    The fate of acetone in an outdoor model stream to which nitrate was added as a nutrient supplement was determined. The stream, in southern Mississippi, U.S.A. was 234 m long. Water was supplied to the stream by an artesian well at about 1.21 s-1, resulting in a mean water velocity of about 0.5 m min-1. Acetone was injected continuously for 26 days resulting in concentrations of 20-40 mg l-1. A nitrate solution was injected for 21 days resulting in an instream concentration of about 1.7 mg l-1 at the upstream end of the stream. Rhodamine-WT dye was used to determine the travel time and dispersion characteristics of the stream, and t-butyl alcohol was used to determine the volatilization characteristics. Volatilization controlled the fate of acetone in the model stream. The lack of substantial bacterial degradation of acetone was contrary to expectations based on the results of laboratory degradation studies using model stream water enriched with nitrate. A possible explanation for the lack of significant degradation in the model stream may be the limited 6-h residence time of the acetone in the stream. ?? 1991.

  19. Stereoselective reduction of ethyl 4-chloro-3-oxobutanoate by fungi.

    PubMed

    Saratani, Y; Uheda, E; Yamamoto, H; Nishimura, A; Yoshizako, F

    2001-07-01

    The enantioselectivity of ECAA to ECHB by eight fungi of four genus was evaluated. All strains showed (S)-selectivity, and Cylindrocarpon sclerotigenum IFO 31855 gave the highest yield and good optical purity (e.e.; >99%). Cell-free extract and acetone-dried cells of C. sclerotigenum IFO 31855 reduced ECAA to (S)-ECHB in the presence of NADPH (e.e.; >99%) and the e.e. was not decreased by heat treatment of the cell-free extract or the acetone-dried cells. The active fractions shown by two peaks on a DEAE-Toyopearl 650 M column gave preferentially (S)-ECHB (e.e.; >99%). PMID:11515558

  20. Fragrance material review on 2-(p-tolyloxy)ethyl acetate.

    PubMed

    McGinty, D; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 2-(p-tolyloxy)ethyl acetate when used as a fragrance ingredient is presented. 2-(p-tolyloxy)ethyl acetate is a member of the fragrance structural group aryl alkyl alcohol simple acid esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 2-(p-tolyloxy)ethyl acetate were evaluated, then summarized, and includes physical properties data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances. PMID:22414652

  1. NEW GROUND-STATE MEASUREMENTS OF ETHYL CYANIDE

    SciTech Connect

    Brauer, Carolyn S.; Pearson, John C.; Drouin, Brian J.; Yu, Shanshan

    2009-09-01

    The spectrum of ethyl cyanide, or propionitrile (CH{sub 3}CH{sub 2}CN), has been repeatedly observed in the interstellar medium with large column densities and surprisingly high temperatures in hot core sources. The construction of new, more sensitive, observatories accessing higher frequencies such as Herschel, ALMA, and SOFIA have made it important to extend the laboratory data for ethyl cyanide to coincide with the capabilities of the new instruments. We report extensions of the laboratory measurements of the rotational spectrum of ethyl cyanide in its ground vibrational state to 1.6 THz. A global analysis of the ground state, which includes all of the previous data and 3356 newly assigned transitions, has been fitted to within experimental error to J = 132, K = 36, using both Watson A-reduced and Watson S-reduced Hamiltonians.

  2. The role of renal proximal tubule P450 enzymes in chloroform-induced nephrotoxicity: Utility of renal specific P450 reductase knockout mouse models

    SciTech Connect

    Liu, Senyan; Yao, Yunyi; Lu, Shijun; Aldous, Kenneth; Ding, Xinxin; Mei, Changlin; Gu, Jun

    2013-10-01

    The kidney is a primary target for numerous toxic compounds. Cytochrome P450 enzymes (P450) are responsible for the metabolic activation of various chemical compounds, and in the kidney are predominantly expressed in proximal tubules. The aim of this study was to test the hypothesis that renal proximal tubular P450s are critical for nephrotoxicity caused by chemicals such as chloroform. We developed two new mouse models, one having proximal tubule-specific deletion of the cytochrome P450 reductase (Cpr) gene (the enzyme required for all microsomal P450 activities), designated proximal tubule-Cpr-null (PTCN), and the other having proximal tubule-specific rescue of CPR activity with the global suppression of CPR activity in all extra-proximal tubular tissues, designated extra-proximal tubule-Cpr-low (XPT-CL). The PTCN, XPT-CL, Cpr-low (CL), and wild-type (WT) mice were treated with a single oral dose of chloroform at 200 mg/kg. Blood, liver and kidney samples were obtained at 24 h after the treatment. Renal toxicity was assessed by measuring BUN and creatinine levels, and by pathological examination. The blood and tissue levels of chloroform were determined. The severity of toxicity was less in PTCN and CL mice, compared with that of WT and XPT-CL mice. There were no significant differences in chloroform levels in the blood, liver, or kidney, between PTCN and WT mice, or between XPT-CL and CL mice. These findings indicate that local P450-dependent activities play an important role in the nephrotoxicity induced by chloroform. Our results also demonstrate the usefulness of these novel mouse models for studies of chemical-induced kidney toxicity. - Highlights: • New mouse models were developed with varying P450 activities in the proximal tubule. • These mouse models were treated with chloroform, a nephrotoxicant. • Studies showed the importance of local P450s in chloroform-induced nephrotoxicity.

  3. The use of alkaline hydrolysis as a novel strategy for chloroform remediation: the feasibility of using construction wastes and evaluation of carbon isotopic fractionation.

    PubMed

    Torrentó, Clara; Audí-Miró, Carme; Bordeleau, Geneviève; Marchesi, Massimo; Rosell, Mònica; Otero, Neus; Soler, Albert

    2014-01-01

    Laboratory and field-scale pilot experiments were performed to evaluate the feasibility of chloroform degradation by alkaline hydrolysis and the potential of δ(13)C values to assess this induced reaction process at contaminated sites. In batch experiments, alkaline conditions were induced by adding crushed concrete (pH 12.33 ± 0.07), a filtered concrete solution (pH 12.27 ± 0.04), a filtered cement solution (pH 12.66 ± 0.02) and a pH 12 buffer solution (pH 11.92 ± 0.11). The resulting chloroform degradation after 28 days was 94, 96, 99, and 72%, respectively. The experimental data were described using a pseudo-first-order kinetic model, resulting in pseudo-first-order rate constant values of 0.10, 0.12, 0.20, and 0.05 d(-1), respectively. Furthermore, the significant chloroform carbon isotopic fractionation associated with alkaline hydrolysis of chloroform (-53 ± 3‰) and its independence from pH in the admittedly limited tested pH range imply a great potential for the use of δ(13)C values for in situ monitoring of the efficacy of remediation approaches based on alkaline hydrolysis. The carbon isotopic fractionation obtained at the lab scale allowed the calculation of the percentage of chloroform degradation in field-scale pilot experiments where alkaline conditions were induced in two recharge water interception trenches filled with concrete-based construction wastes. A maximum of approximately 30-40% of chloroform degradation was achieved during the two studied recharge periods. Although further research is required, the treatment of chloroform in groundwater through the use of concrete-based construction wastes is proposed. This strategy would also imply the recycling of construction and demolition wastes for use in value-added applications to increase economic and environmental benefits. PMID:24410407

  4. Anti-inflammatory effects of the chloroform extract of Pulicaria guestii ameliorated the neutrophil infiltration and nitric oxide generation in rats.

    PubMed

    Alghaithy, A A; El-Beshbishy, H A; Abdel-Naim, A B; Nagy, A A; Abdel-Sattar, E M

    2011-11-01

    Pulicaria guestii Rech.f. & Rawi is a fragrant, perennial herb, which grows wild, west of Al-Madinah, Saudi Arabia. Several reports were published on the anti-inflammatory activity of the sesquiterpene lactones, phenolics and flavonoids, which constitute the main active constituents of the members of the genus Pulicaria. The present study was designed to explore the potential anti-inflammatory effect of P. guestii in several experimental models. The methanol extract of the dried aerial parts of P. guestii was extracted with petroleum ether, chloroform and n-butanol. The chloroform extract was analysed on TLC and examined under UV and visible light in presence of AlCl(3) spray. The free radical scavenging activity and the total phenolic content in the CHCl(3) extract were estimated. The crude methanol extract and the CHCl(3) fraction were examined against carrageenin-induced paw edema and ear edema induced by croton oil application. The crude methanolic extract significantly reduced carrageenin-induced rat paw edema. After fractionation, the chloroform fraction caused significant reduction in carrageenin-induced rat paw edema in addition to diminishing prostaglandin E(2) (PGE(2)) in the inflammatory exudates. Topical application of chloroform fraction significantly reduced rat ear edema induced by croton oil application. In the same model, chloroform fraction reduced neutrophil infiltration, as indicated by the significant decrease in myeloperoxidase activity, and ameliorated histopathological changes induced by croton oil application. In lipopolysaccharide-induced inflammation in rat air pouch, chloroform fraction significantly reduced the nitric oxide level and tumor necrosis factor-α release. In conclusion, the chloroform fraction of P. guestii extract possesses anti-inflammatory activity in several experimental models. Further investigations are needed to identify the active constituents responsible for this anti-inflammatory activity. PMID:21505007

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

    PubMed Central

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

    1971-01-01

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

  6. Determination of induction period and crystal growth mechanism of dexamethasone sodium phosphate in methanol-acetone system

    NASA Astrophysics Data System (ADS)

    Hao, Hongxun; Wang, Jingkang; Wang, Yongli

    2005-02-01

    The induction period of dexamethasone sodium phosphate at different supersaturation was experimentally determined in a methanol-acetone system. The laser monitoring observation technique was used to determine the appearance of the first nucleus in solution. The effect of solution composition on induction period was discussed. Based on classical homogeneous nucleation theory, the solid-liquid interfacial tension and surface entropy factor were calculated from the induction period data. The experimentally determined values of interfacial tension are in agreement with the theoretical values predicted by the Mersmann equation. It was found that the nucleus of dexamethasone sodium phosphate grows continuously in pure methanol and turns from continuous growth to birth and spread growth with increasing acetone content in a methanol-acetone mixture.

  7. Hydrothermal Synthesis of ZnO Structures Formed by High-Aspect-Ratio Nanowires for Acetone Detection.

    PubMed

    Cao, Zhen; Wang, Yong; Li, Zhanguo; Yu, Naisen

    2016-12-01

    Snowflake-like ZnO structures originating from self-assembled nanowires were prepared by a low-temperature aqueous solution method. The as-grown hierarchical ZnO structures were investigated by X-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM). The results showed that the snowflake-like ZnO structures were composed of high-aspect-ratio nanowires. Furthermore, gas-sensing properties to various testing gases of 10 and 50 ppm were measured, which confirms that the ZnO structures were of good selectivity and response to acetone and could serve for acetone sensor to detect low-concentration acetone. PMID:27460595

  8. A QSPR study on the solvent-induced frequency shifts of acetone and dimethyl sulfoxide in organic solvents

    NASA Astrophysics Data System (ADS)

    Ou, Yu Heng; Chang, Chia Ming; Chen, Ying Shao

    2016-06-01

    In this study, solvent-induced frequency shifts (SIFS) in the infrared spectrum of acetone and dimethyl sulfoxide in organic solvents were investigated by using four types of quantum-chemical reactivity descriptors. The results showed that the SIFS of acetone is mainly affected by the electron-acceptance chemical potential and the maximum nucleophilic condensed local softness of organic solvents, which represent the electron flow and the polarization between acetone and solvent molecules. On the other hand, the SIFS of dimethyl sulfoxide changes with the maximum positive charge of hydrogen atom and the inverse of apolar surface area of solvent molecules, showing that the electrostatic and hydrophilic interactions are main mechanisms between dimethyl sulfoxide and solvent molecules. The introduction of the four-element theory model-based quantitative structure-property relationship approach improved the assessing quality and provided a basis for interpreting the solute-solvent interactions.

  9. A QSPR study on the solvent-induced frequency shifts of acetone and dimethyl sulfoxide in organic solvents.

    PubMed

    Ou, Yu Heng; Chang, Chia Ming; Chen, Ying Shao

    2016-06-01

    In this study, solvent-induced frequency shifts (SIFS) in the infrared spectrum of acetone and dimethyl sulfoxide in organic solvents were investigated by using four types of quantum-chemical reactivity descriptors. The results showed that the SIFS of acetone is mainly affected by the electron-acceptance chemical potential and the maximum nucleophilic condensed local softness of organic solvents, which represent the electron flow and the polarization between acetone and solvent molecules. On the other hand, the SIFS of dimethyl sulfoxide changes with the maximum positive charge of hydrogen atom and the inverse of apolar surface area of solvent molecules, showing that the electrostatic and hydrophilic interactions are main mechanisms between dimethyl sulfoxide and solvent molecules. The introduction of the four-element theory model-based quantitative structure-property relationship approach improved the assessing quality and provided a basis for interpreting the solute-solvent interactions. PMID:26994584

  10. Change in tensile properties of neoprene and nitrile gloves after repeated exposures to acetone and thermal decontamination.

    PubMed

    Gao, Pengfei; Tomasovic, Beth

    2005-11-01

    This study investigated the change in tensile properties of neoprene and nitrile gloves after repeated cycles of exposure to acetone, followed by thermal decontamination. The glove was exposed to acetone (outer surface in contact with chemical), subjected to thermal decontamination, and tested for the tensile strength and the ultimate elongation. Thermal decontamination was carried out inside an oven for 16 hours at 100 degrees C. The exposure/decontamination procedure was repeated for a maximum of 10 cycles. For neoprene versus acetone, the mean tensile strength consistently decreased after each exposure/decontamination cycle. Multiple comparisons indicated that the mean tensile strengths between the new swatches and each exposure/decontamination group were significantly different (p < 0.05). The loss of either tensile strength or ultimate elongation was less than 23% compared with new swatches after four exposure/decontamination cycles. Swatches with out acetone exposure were then cycled through the oven in the same manner. It was found that both the heat used for thermal decontamination and acetone exposure significantly affected the tensile strength and ultimate elongation. For nitrile gloves exposed to acetone, the mean tensile strength remained virtually unchanged (p > 0.05). The mean tensile strength for the new swatches was 37.1 MPa and the mean tensile strength after nine exposure/decontamination cycles was 36.0 MPa, with a loss less than 3%. The largest single cycle loss for ultimate elongation occurred during the first exposure/decontamination cycle for both glove materials. In our previous study, decisions regarding the effectiveness of the decontamination process were based on having no discernible change in the breakthrough time and steady-state permeation rate. The results of this study indicate that the effectiveness of the decontamination process cannot be based on permeation parameters alone but must also take into account the change in physical

  11. Hepatotoxic effects of chloroform extract of Artemisia macivera Linn in rats following intraperitoneal administration of different subchronic doses.

    PubMed

    Atawodi, S E; Ene, A C; Ameh, D A

    2011-01-01

    The possible hepatotoxic effects of chloroform extract of Artemisia maciverae was evaluated biochemically and histologically using male Swiss albino rats, randomly assigned into four groups of 24 animals each. The groups (control, 50, 100 and 200 mg/kg body weight) were treated for 60 days and then monitored for another 30 days before sacrifice. Alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, bilirubin (total and direct), total protein and albumin were assessed colorimetrically, while tissue specimens were subjected to histological examination following standard hematoxyline-eosin staining techniques. After 1 week of treatment, the extract caused statistically significant elevation in levels of serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and bilirubin (total and direct), while there was significant (p < 0.05) decrease in the levels of serum total protein and albumin at the onset of treatment when compared with the control. These abnormalities in the levels of serum biochemical parameters were spontaneously corrected within 2 weeks of treatment. Similarly, histological assessment showed severe hepatic tissue injuries after 1 week, but these organs recovered spontaneously by the second week of treatment. The results indicate that long-term exposure to therapeutic doses of chloroform extract of A maciverae is relatively safe, but high dose exposure may result in hepatocellular injury. PMID:20385704

  12. Crystal structure of Boc-(S)-ABOC-(S)-Ala-(S)-ABOC-(S)-Phe-OBn chloro-form monosolvate.

    PubMed

    Wenger, Emmanuel; Moulat, Laure; Legrand, Baptiste; Amblard, Muriel; Calmès, Monique; Didierjean, Claude

    2015-10-01

    In the title compound, phenyl (S)-2-[(S)-(1-{2-[(S)-(1-{[(tert-but-oxy)carbon-yl]amino}-bicyclo-[2.2.2]octan-2-yl)formamido]-propanamido}-bicyclo-[2.2.2]octan-2-yl)formamido]-3-phenyl-propano-ate chloro-form monosolvate, C42H56N4O7·CHCl3, the α,β-hybrid peptide contains two non-proteinogenic amino acid residues of (S)-1-amino-bicyclo-[2.2.2]octane-2-carb-oxy-lic acid [(S)-ABOC], two amino acid residues of (S)-2-amino-propanoic acid [(S)-Ala] and (S)-2-amino-3-phenyl-propanoic acid [(S)-Phe], and protecting groups of tert-but-oxy-carbonyl (Boc) and benzyl ester (OBn). The tetra-mer folds into a right-handed mixed 11/9 helix stabilized by intra-molecular i,i + 3 and i,i - 1 C=O⋯H-N hydrogen bonds. In the crystal, the oligomers are linked by N-H⋯O=C hydrogen bonds into chains along the a-axis direction. The chloro-form solvent mol-ecules are inter-calated between the folded chains via C-H⋯O=C inter-actions. PMID:26594404

  13. Synthesis, growth, structural, thermal, optical properties of new metal-organic crystals: Methyltriphenylphosphonium iodide thiourea and methyltriphenylphosphonium iodide chloroform hemisolvate

    NASA Astrophysics Data System (ADS)

    Shivachev, Boris L.; Kossev, Krassimir; Dimowa, Louiza T.; Yankov, Georgi; Petrov, Todor; Nikolova, Rositsa P.; Petrova, Nadia

    2013-08-01

    Crystals of methyltriphenylphosphonium iodide thiourea (1) and methyltriphenylphosphonium iodide chloroform hemisolvate (2) were obtained for the first time. Fourier transform infrared (FTIR) spectral studies have been performed to identify the functional groups. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) were used to study their thermal properties. The optical transmittance window and the lower cutoff wavelength have been identified by UV-vis studies. Crystals of the title compounds suitable for single crystal X-ray analyses were successfully grown by slow evaporation and diffraction data were collected to elucidate the molecular structure and interactions. The proton donors (phosphonium) and proton acceptor (iodine) in the structure of 1 provide infrastructure to introduce charge asymmetry while in 2 chloroform molecule is not involved in the charge transfer. An optical quality crystal of 1 (5×4×2 mm3) was obtained by macroseeding. The crystal has developed facets with major ones (001) and (00¯1). A crystal of 1 was tested with 1060 nm laser radiation and showed second harmonic generation (SHG).

  14. Spectroscopic analysis of porphyrin compounds irradiated with visible light in chloroform with addition of β-myrcene

    NASA Astrophysics Data System (ADS)

    Makarska-Bialokoz, Magdalena; Gladysz-Plaska, Agnieszka

    2016-12-01

    The behaviour of two porphyrins, 5,10,15,20-tetraphenyl-21H,23H-porphine (H2TPP) and 5,10,15,20-tetra(4-pyridyl)-21H, 23H-porphine (H2TPyP), as well as their Zn(II) complexes (ZnTPP and ZnTPyP), have been studied analysing their absorption and steady-state fluorescence spectra in chloroform with addition of β-myrcene. After irradiation with visible light the free-base porphyrins have been converted to the form of dication on account of hydrochloric acid generated as a result of chloroform decomposition induced by β-myrcene. Whereas in case of their Zn(II) complexes the mechanism of action is more complicated, leading presumably to the formation of the aggregated metalloporphyrin species with chloride ions playing the bridging role. The pseudo-first-order rate constants of the absorption quenching process were calculated for all the systems examined, with respect to the porphyrin concentration. The most effective irradiation was observed in case of H2TPP porphyrin.

  15. Morphological Evolution of Noble Metal Nanoparticles in Chloroform: Mechanism of Switching on/off by Protic Species

    PubMed Central

    Douglas-Gallardo, O. A.; Gomez, C. G.; Macchione, M. A.; Cometto, F. P.; Coronado, E. A.; Macagno, V. A.; Pérez, M. A.

    2015-01-01

    The morphological stability/morphological reshaping of noble metal nanoparticles are studied experimentally in order to unravel the chemical mechanisms lying beneath. Gold and silver nanoparticles (AuNPs and AgNPs, respectively) formed in chloroformic environment are used, as model synthetic systems, to study phenomena of morphological change. The morphological evolution of NPs that follows their formation, is characterized by spectroscopy (UV-Visible, Raman and FTIR) and TEM (Transmission Electron Microscopy). The change of NP morphology involves the increase of the average NP size and the broadening of size distribution, in a close resemblance with the effect characteristically obtained from the Ostwald ripening. The effect of the poor solvating properties of chloroform in stabilizing small charged species (H+, Ag+, Au+) as well as the principle of electroneutrality of matter are analyzed in order to formulate a feasible reaction scheme consisting of a three-step processes: the generation of soluble intermediary species by corrosion of nanoparticles, the diffusion of intermediary species from one nanoparticle to another, and the re-deposition process involving the reduction of intermediary species. This basic reaction scheme is used as hypothesis to plan and perform experiments, which reveal that molecular oxygen dissolved in the dispersive medium can drive NP corrosion, however, protic species are also required as co-reactant. The polarity of the hydrogen bond and the ligand properties of the anions produced by deprotonation are feature of the protic species that enable/disable the corrosion and, in turn, the NP morphological evolution. PMID:26889378

  16. Assistance of ethyl glucuronide and ethyl sulfate in the interpretation of postmortem ethanol findings.

    PubMed

    Krabseth, Hege; Mørland, Jørg; Høiseth, Gudrun

    2014-09-01

    Postmortem ethanol formation is a well-known problem in forensic toxicology. The aim of this study was to interpret findings of ethanol in blood, in a large collection of forensic autopsy cases, by use of the nonoxidative ethanol metabolites, ethyl glucuronide (EtG), and ethyl sulfate (EtS). In this study, according to previously published literature, antemortem ethanol ingestion was excluded in EtS-negative cases. Among 493 ethanol-positive forensic autopsy cases, collected during the study period, EtS was not detected in 60 (12 %) of the cases. Among cases with a blood alcohol concentration (BAC) of ≤ 0.54 g/kg, antemortem ethanol ingestion was excluded in 38 % of the cases, while among cases with a BAC of ≥ 0.55 g/kg, antemortem ethanol ingestion was excluded in 2.2 % of the cases. For all cases where ethanol was measured at a concentration >1.0 g/kg, EtS was detected. The highest blood ethanol concentration in which EtS was not detected was 1.0 g/kg. The median concentrations of EtG and EtS in blood were 9.5 μmol/L (range: not detected (n.d.) 618.1) and 9.2 μmol/L (range: n.d. 182.5), respectively. There was a statistically significant positive correlation between concentration levels of ethanol and of EtG (Spearman's rho=0.671, p<0.001) and EtS (Spearman's rho=0.670, p<0.001), respectively. In conclusion, this study showed that in a large number of ethanol-positive forensic autopsy cases, ethanol was not ingested before the time of death, particularly among cases where ethanol was present in lower blood concentrations. Routine measurement of EtG and EtS should therefore be recommended, especially in cases with BAC below 1 g/kg. PMID:24935750

  17. Blood kinetics of ethyl glucuronide and ethyl sulphate in heavy drinkers during alcohol detoxification.

    PubMed

    Høiseth, Gudrun; Morini, Luca; Polettini, Aldo; Christophersen, Asbjørg; Mørland, Jørg

    2009-07-01

    Studies of ethyl glucuronide (EtG) blood kinetics have so far been performed on healthy volunteers with ingestion of low to moderate doses of ethanol. These data are not necessarily transferable to heavy drinkers where the consumed doses of ethanol are much higher. The aim of this study was to investigate the pharmacokinetics of EtG and ethyl sulphate (EtS) in blood in heavy drinkers after termination of alcohol ingestion. Sixteen patients from an alcohol withdrawal clinic were included directly after admission. Time of end of drinking, estimated daily intake of ethanol (EDI) and medical history were recorded. Three to five blood samples over 20-43 h were collected from each patient subsequent to admission. The median EDI was 172 g (range 60-564). The first sample was collected median 2.5 h after end of drinking (range 0.5-23.5). Two patients had levels of EtG and EtS below LOQ in all samples, the first collected 19.25 and 23.5 h after cessation of drinking, respectively. Of the remaining 14 patients, one subject, suffering from both renal and hepatic disease, showed concentrations of EtG and EtS substantially higher than the rest of the material. This patient's initial value of EtG was 17.9 mg/L and of EtS 5.9 mg/L, with terminal elimination half lives of 11.9 h for EtG and 12.5 h for EtS. Among the remaining 13 patients, the initial median values were 0.7 g/L (range 0-3.7) for ethanol, 1.7 mg/L (range 0.1-5.9) for EtG and 0.9 mg/L (range 0.1-1.9) for EtS. Elimination occurred with a median half-life of 3.3 h for EtG (range 2.6-4.3) and 3.6 h for EtS (range 2.7-5.4). In conclusion, elimination of EtG in heavy drinkers did not significantly differ from healthy volunteers, and EtS appeared to have similar elimination rate. In the present work, there was one exception to this, and we propose that this could be explained by the patient's renal disease, which would delay excretion of these conjugated metabolites. PMID:19395207

  18. Ethyl glucuronide and ethyl sulfate in meconium and hair-potential biomarkers of intrauterine exposure to ethanol.

    PubMed

    Morini, L; Marchei, E; Vagnarelli, F; Garcia Algar, O; Groppi, A; Mastrobattista, L; Pichini, S

    2010-03-20

    This study investigated ethyl glucuronide (EtG) and ethyl sulfate (EtS) concentration in meconium and in maternal and neonatal hair (HEtG and HFAEEs, respectively) as potential markers of intrauterine exposure to ethanol together with meconium fatty acid ethyl esters (FAEEs) in a cohort of 99 mother-infant dyads, 49 coming from the Arcispedale of Reggio Emilia (Italy) and 50 from the Hospital del Mar of Barcelona (Spain). FAEEs, EtG and EtS were measured in meconium samples using liquid chromatography-tandem mass spectrometry. A head space-solid phase microextraction-gas chromatography-mass spectrometry was used to test HEtG and HFAEEs in hair samples from mothers and their newborns. Eighty-two meconium samples (82.8%) tested positive for EtG, 19 (19.2%) for EtS while 22 (22.2%) showed FAEEs levels higher than 2 nmol/g, the cut-off used to differentiate daily maternal ethanol consumption during pregnancy from occasional or no use. Although EtG and EtS in meconium did not correlate with total FAEEs concentration, a good correlation between EtG, EtS and ethyl stearate was observed. Moreover, EtG correlated well with ethyl palmitoleate, while EtS with ethyl laurate, myristate and linolenate. Neither maternal nor neonatal hair appears as good predictors of gestational ethanol consumption and subsequent fetal exposure in these mother-infant dyads. In conclusion, these data show that meconium is so far the best matrix in evaluating intrauterine exposure to ethanol, with EtG and EtS being potentially good alternative biomarkers to FAEEs. PMID:20060246

  19. Novel spectrophotometric method for detection and estimation of butanol in acetone-butanol-ethanol fermenter.

    PubMed

    Maiti, Sampa; Sarma, Saurabh Jyoti; Brar, Satinder Kaur; Bihan, Yann Le; Drogui, Patrick; Buelna, Gerardo; Verma, Mausam; Soccol, Carlos Ricardo

    2015-08-15

    A new, simple, rapid and selective spectrophotometric method has been developed for detection and estimation of butanol in fermentation broth. The red colored compound, produced during reduction of diquat-dibromide-monohydrate with 2-mercaptoethanol in aqueous solution at high pH (>13), becomes purple on phase transfer to butanol and gives distinct absorption at λ520nm. Estimation of butanol in the fermentation broth has been performed by salting out extraction (SOE) using saturated K3PO4 solution at high pH (>13) followed by absorbance measurement using diquat reagent. Compatibility and optimization of diquat reagent concentration for detection and estimation of butanol concentration in the fermentation broth range was verified by central composite design. A standard curve was constructed to estimate butanol in acetone-ethanol-butanol (ABE) mixture under optimized conditions. The spectrophotometric results for butanol estimation, was found to have 87.5% concordance with the data from gas chromatographic analysis. PMID:25966390

  20. Investigating Solvent Purity Utilizing Comprehensive Gas Chromatography: A Study of Acetones

    SciTech Connect

    Wahl, Jon H.; Bolz, Cinnamon DH; Wahl, Karen L.

    2010-04-01

    Broad spectrum chemical analysis of trace level components is a continuing challenge for any analytical chemist. This challenge is further confounded when chemical impurities may be present in common organic solvents or when chemical artifacts may be formed, produced and introduced during an analytical procedure. Minimizing and understanding these chemical artifacts, is critical for trace level detection and is crucial for unambiguous analytical results. Comprehensive gas chromatography is an excellent analytical tool to help address these complex mixture challenges. This work examines the impurities present in various acetone sources utilizing comprehensive gas chromatography. This work highlights the extreme variability possible in solvent sources and hence the importance of understanding the impurities that may confound an analytical method or result.