Insights into Mechanistic Models for Evaporation of Organic Liquids in the Environment Obtained by Position-Specific Carbon Isotope Analysis.

Science.gov (United States)

Julien, Maxime; Nun, Pierrick; Robins, Richard J; Remaud, Gérald S; Parinet, Julien; Höhener, Patrick

2015-11-03

Position-specific isotope effects (PSIEs) have been measured by isotope ratio monitoring (13)C nuclear magnetic resonance spectrometry during the evaporation of 10 liquids of different polarities under 4 evaporation modes (passive evaporation, air-vented evaporation, low pressure evaporation, distillation). The observed effects are used to assess the validity of the Craig-Gordon isotope model for organic liquids. For seven liquids the overall isotope effect (IE) includes a vapor-liquid contribution that is strongly position-specific in polar compounds but less so in apolar compounds and a diffusive IE that is not position-specific, except in the alcohols, ethanol and propan-1-ol. The diffusive IE is diminished under forced evaporation. The position-specific isotope pattern created by liquid-vapor IEs is manifest in five liquids, which have an air-side limitation for volatilization. For the alcohols, undefined processes in the liquid phase create additional PSIEs. Three other liquids with limitations on the liquid side have a lower, highly position-specific, bulk diffusive IE. It is concluded that evaporation of organic pollutants creates unique position-specific isotope patterns that may be used to assess the progress of remediation or natural attenuation of pollution and that the Craig-Gordon isotope model is valid for the volatilization of nonpolar organic liquids with air-side limitation of the volatilization rate.

Characteristics of a non-volatile liquid propellant in liquid-fed ablative pulsed plasma thrusters

Science.gov (United States)

Ling, William Yeong Liang; Schönherr, Tony; Koizumi, Hiroyuki

2017-02-01

In the past several decades, the use of electric propulsion in spacecraft has experienced tremendous growth. With the increasing adoption of small satellites in the kilogram range, suitable propulsion systems will be necessary in the near future. Pulsed plasma thrusters (PPTs) were the first form of electric propulsion to be deployed in orbit, and are highly suitable for small satellites due to their inherent simplicity. However, their lifetime is limited by disadvantages such as carbon deposition leading to thruster failure, and complicated feeding systems required due to the conventional use of solid propellants (usually polytetrafluoroethylene (PTFE)). A promising alternative to solid propellants has recently emerged in the form of non-volatile liquids that are stable in vacuum. This study presents a broad comparison of the non-volatile liquid perfluoropolyether (PFPE) and solid PTFE as propellants on a PPT with a common design base. We show that liquid PFPE can be successfully used as a propellant, and exhibits similar plasma discharge properties to conventional solid PTFE, but with a mass bit that is an order of magnitude higher for an identical ablation area. We also demonstrate that the liquid PFPE propellant has exceptional resistance to carbon deposition, completely negating one of the major causes of thruster failure, while solid PTFE exhibited considerable carbon build-up. Energy dispersive X-ray spectroscopy was used to examine the elemental compositions of the surface deposition on the electrodes and the ablation area of the propellant (or PFPE encapsulator). The results show that based on its physical characteristics and behavior, non-volatile liquid PFPE is an extremely promising propellant for use in PPTs, with an extensive scope available for future research and development.

Volatilization behavior of semivolatile elements in vitrification of high-level liquid waste

International Nuclear Information System (INIS)

Igarashi, Hiroshi; Kato, Koh; Takahashi, Takeshi

1991-11-01

The effect of temperature on the volatilization of ruthenium, technetium, and selenium was observed in calcination experiments with simulated high-level liquid waste. Technetium and selenium were more volatile as calcining temperature increased. Ruthenium was less volatile when temperature exceeded 300degC. More than 80% of ruthenium that volatilized from room temperature to 500degC occurred between 200 and 300degC. A small amount of ruthenium volatilized above 300degC as well as below 135degC. (author)

Nonvolatile, semivolatile, or volatile: redefining volatile for volatile organic compounds.

Science.gov (United States)

Võ, Uyên-Uyén T; Morris, Michael P

2014-06-01

Although widely used in air quality regulatory frameworks, the term "volatile organic compound" (VOC) is poorly defined. Numerous standardized tests are currently used in regulations to determine VOC content (and thus volatility), but in many cases the tests do not agree with each other, nor do they always accurately represent actual evaporation rates under ambient conditions. The parameters (time, temperature, reference material, column polarity, etc.) used in the definitions and the associated test methods were created without a significant evaluation of volatilization characteristics in real world settings. Not only do these differences lead to varying VOC content results, but occasionally they conflict with one another. An ambient evaporation study of selected compounds and a few formulated products was conducted and the results were compared to several current VOC test methodologies: SCAQMD Method 313 (M313), ASTM Standard Test Method E 1868-10 (E1868), and US. EPA Reference Method 24 (M24). The ambient evaporation study showed a definite distinction between nonvolatile, semivolatile, and volatile compounds. Some low vapor pressure (LVP) solvents, currently considered exempt as VOCs by some methods, volatilize at ambient conditions nearly as rapidly as the traditional high-volatility solvents they are meant to replace. Conversely, bio-based and heavy hydrocarbons did not readily volatilize, though they often are calculated as VOCs in some traditional test methods. The study suggests that regulatory standards should be reevaluated to more accurately reflect real-world emission from the use of VOC containing products. The definition of VOC in current test methods may lead to regulations that exclude otherwise viable alternatives or allow substitutions of chemicals that may limit the environmental benefits sought in the regulation. A study was conducted to examine volatility of several compounds and a few formulated products under several current VOC test

Turbulence effects on volatilization rates of liquids and solutes

Science.gov (United States)

Lee, J.-F.; Chao, H.-P.; Chiou, C.T.; Manes, M.

2004-01-01

Volatilization rates of neat liquids (benzene, toluene, fluorobenzene, bromobenzene, ethylbenzene, m-xylene, o-xylene, o-dichlorobenzene, and 1-methylnaphthalene) and of solutes (phenol, m-cresol, benzene, toluene, ethylbenzene, o-xylene, and ethylene dibromide) from dilute water solutions have been measured in the laboratory over a wide range of air speeds and water-stirring rates. The overall transfer coefficients (KL) for individual solutes are independent of whether they are in single- or multi-solute solutions. The gas-film transfer coefficients (kG) for solutes in the two-film model, which have hitherto been estimated by extrapolation from reference coefficients, can now be determined directly from the volatilization rates of neatliquids through anew algorithm. The associated liquid-film transfer coefficients (KL) can then be obtained from measured KL and kG values and solute Henry law constants (H). This approach provides a novel means for checking the precision of any kL and kG estimation methods for ultimate prediction of KL. The improved kG estimation enables accurate K L predictions for low-volatility (i.e., low-H) solutes where K L and kGH are essentially equal. In addition, the prediction of KL values for high-volatility (i.e., high-H) solutes, where KL ??? kL, is also improved by using appropriate reference kL values.

Contaminants in Liquid Organic Fertilizers Used for Agriculture in Japan.

Science.gov (United States)

Hai, Dao M; Qiu, Xuchun; Xu, Hai; Honda, Masato; Yabe, Mitsuyasu; Kadokami, Kiwao; Shimasaki, Yohei; Oshima, Yuji

2017-07-01

To provide an overview of anthropogenic contaminants in liquid organic fertilizers (LOFs), products from four biogas plants in Kyushu, Japan, were analyzed for a wide range of contaminants, including copper, cadmium, tributyltin (TBT), dibutyltin (DBT), perfluorooctane sulfonate, 952 semi-volatile organic compounds, and 89 antibiotics. The highest concentrations of copper (31.1 mg/L) and cadmium (0.08 mg/L) were found in LOFs from the Hita biogas plant. Only ofloxacin and sulfapyridine were detected in total 89 antibiotics screened. TBT, DBT, and perfluorooctane sulfonate were present at low concentrations in the LOFs from all four locations. Among the 952 semi-volatile organic compounds, 78 compounds were detected in at least one sample and were present at concentrations between 1.2 and 139.6 mg/L. On the basis of comparisons with previous studies and quality standards for the use of organic fertilizers, the concentrations of contaminants in the studied LOFs indicate that they might be safe for agricultural purposes.

Dispersive liquid-liquid microextraction and gas chromatography accurate mass spectrometry for extraction and non-targeted profiling of volatile and semi-volatile compounds in grape marc distillates.

Science.gov (United States)

Fontana, Ariel; Rodríguez, Isaac; Cela, Rafael

2018-04-20

The suitability of dispersive liquid-liquid microextraction (DLLME) and gas chromatography accurate mass spectrometry (GC-MS), based on a time-of-flight (TOF) MS analyzer and using electron ionization (EI), for the characterization of volatile and semi-volatile profiles of grape marc distillates (grappa) are evaluated. DLLME conditions are optimized with a selection of compounds, from different chemical families, present in the distillate spirit. Under final working conditions, 2.5 mL of sample and 0.5 mL of organic solvents are consumed in the sample preparation process. The absolute extraction efficiencies ranged from 30 to 100%, depending on the compound. For the same sample volume, DLLME provided higher responses than solid-phase microextraction (SPME) for most of the model compounds. The GC-EI-TOF-MS records of grappa samples were processed using a data mining non-targeted search algorithm. In this way, chromatographic peaks and accurate EI-MS spectra of sample components were linked. The identities of more than 140 of these components are proposed from comparison of their accurate spectra with those in a low resolution EI-MS database, accurate masses of most intense fragment ions of known structure, and available chromatographic retention index. The use of chromatographic and spectral data, associated to the set of components mined from different grappa samples, for multivariate analysis purposes is also illustrated in the study. Copyright © 2018 Elsevier B.V. All rights reserved.

IN SITU MEASUREMENTS OF C2-C10 VOLATILE ORGANIC COMPOUNDS ABOVE A SIERRA NEVADA PONDEROSA PINE PLANTATION

Science.gov (United States)

A fully automated GC-FID system was designed and built to measure ambient concentrations of C2-C10 volatile organic compounds, including many oxygenated compounds, without using liquid cryogen. It was deployed at Blodgett Forest Research Station in Georgetown, CA USA, 38 deg 53' ...

Analysis of volatile organic compounds in pleural effusions by headspace solid-phase microextraction coupled with cryotrap gas chromatography and mass spectrometry.

Science.gov (United States)

Huang, Zhongping; Zhang, Jie; Zhang, Peipei; Wang, Hong; Pan, Zaifa; Wang, Lili

2016-07-01

Headspace solid-phase microextraction coupled with cryotrap gas chromatography and mass spectrometry was applied to the analysis of volatile organic compounds in pleural effusions. The highly volatile organic compounds were separated successfully with high sensitivity by the employment of a cryotrap device, with the construction of a cold column head by freezing a segment of metal capillary with liquid nitrogen. A total of 76 volatile organic compounds were identified in 50 pleural effusion samples (20 malignant effusions and 30 benign effusions). Among them, 34 more volatile organic compounds were detected with the retention time less than 8 min, by comparing with the normal headspace solid-phase microextraction coupled with gas chromatography and mass spectrometry method. Furthermore, 24 volatile organic compounds with high occurrence frequency in pleural effusion samples, 18 of which with the retention time less than 8 min, were selected for the comparative analysis. The results of average peak area comparison and box-plot analysis showed that except for cyclohexanone, 2-ethyl-1-hexanol, and tetramethylbenzene, which have been reported as potential cancer biomarkers, cyclohexanol, dichloromethane, ethyl acetate, n-heptane, ethylbenzene, and xylene also had differential expression between malignant and benign effusions. Therefore, the proposed approach was valuable for the comprehensive characterization of volatile organic compounds in pleural effusions. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Potential for ion-induced nucleation of volatile organic compounds by radon decay in indoor environments

International Nuclear Information System (INIS)

Daisey, J.M.

1991-11-01

There is considerable interest in the ''unattached'' fraction of radon progeny in indoor air because of its significance to the estimation of the risks of radon exposure. Because of its high mobility in air, the unattached fraction is more efficiently deposited in the respiratory tract. Variation in the diameter of the ''unattached'' fraction and in its diffusion coefficient can be due to clustering of other atmospheric species around the 218 PoO 2 + ion. The purpose of this study was to investigate the potential for the formation of clusters of vapor phase organic compounds, found in indoor air, around the 218 PoO 2 + ion and to determine which were most likely to form clusters. A secondary purpose was to provide a compilation of measurements of indoor organic compounds for future experiments and theoretical calculations by the radon research community. The classical charged liquid droplet theory (Thomson equation) was used to estimate the Gibbs free energy of ion-induced nucleation and to provide an indication of the indoor organic compounds most likely to undergo ion-induced nucleation. Forty-four volatile and semi-volatile organic compounds out of the more than 300 which have been reported in indoor air were investigated. Water vapor was included for comparison. The results indicate that there is a potential for the formation of clusters of organic compounds around the 218 PoO 2 + ion. The compounds with the greatest potential for cluster formation are the volatile oxidized hydrocarbons (e.g., n-butanol, phenol, hexanal, nonanal, benzaldehyde, the ketones and the acetates) and the semi-volatile organic compounds (pentachlorophenol, nicotine, chlordane, chlorpyrifos)

Generation of sub-part-per-billion gaseous volatile organic compounds at ambient temperature by headspace diffusion of aqueous standards through decoupling between ideal and nonideal Henry's law behavior.

Science.gov (United States)

Kim, Yong-Hyun; Kim, Ki-Hyun

2013-05-21

In the analysis of volatile organic compounds in air, the preparation of their gaseous standards at low (sub-ppb) concentration levels with high reliability is quite difficult. In this study, a simple dynamic headspace-based approach was evaluated as a means of generating vapor-phase volatile organic compounds from a liquid standard in an impinger at ambient temperature (25 °C). For a given sampling time, volatile organic compound vapor formed in the headspace was swept by bypassing the sweep gas through the impinger and collected four times in quick succession in separate sorbent tubes. In each experiment, a fresh liquid sample was used for each of the four sampling times (5, 10, 20, and 30 min) at a steady flow rate of 50 mL min(-1). The air-water partitioning at the most dynamic (earliest) sweeping stage was established initially in accord with ideal Henry's law, which was then followed by considerably reduced partitioning in a steady-state equilibrium (non-ideal Henry's law). The concentrations of gaseous volatile organic compounds, collected after the steady-state equilibrium, reached fairly constant values: for instance, the mole fraction of toluene measured at a sweeping interval of 10 and 30 min averaged 1.10 and 0.99 nmol mol(-1), respectively (after the initial 10 min sampling). In the second stage of our experiment, the effect of increasing the concentrations of liquid spiking standard was also examined by collecting sweep gas samples from two consecutive 10 min runs. The volatile organic compounds, collected in the first and second 10 min sweep gas samples, exhibited ideal and nonideal Henry's law behavior, respectively. From this observation, we established numerical relationships to predict the mole fraction (or mixing ratio) of each volatile organic compound in steady-state equilibrium in relation to the concentration of standard spiked into the system. This experimental approach can thus be used to produce sub-ppb levels of gaseous volatile organic

Synthesis and toxicity evaluation of hydrophobic ionic liquids for volatile organic compounds biodegradation in a two-phase partitioning bioreactor

International Nuclear Information System (INIS)

Rodriguez Castillo, Alfredo Santiago; Guihéneuf, Solène; Le Guével, Rémy; Biard, Pierre-François

2016-01-01

Highlights: • Description of a VOC depollution system suitable with industrial processes, TPPB. • Novel association of TPPB and hydrophobic ionic liquids. • Synthesis of several hydrophobic ionic liquids designed to fit desired properties. • Toxicity evaluation of these ILs towards cells, animals and bacteria. - Abstract: Synthesis of several hydrophobic ionic liquids (ILs), which might be selected as good candidates for degradation of hydrophobic volatile organic compounds in a two-phase partitioning bioreactor (TPPB), were carried out. Several bioassays were also realized, such as toxicity evaluation on activated sludge and zebrafish, cytotoxicity, fluoride release in aqueous phase and biodegradability in order to verify their possible effects in case of discharge in the aquatic environment and/or human contact during industrial manipulation. The synthesized compounds consist of alkylimidazoliums, functionalized imidazoliums, isoqinoliniums, triazoliums, sulfoniums, pyrrolidiniums and morpholiniums and various counter-ions such as: PF_6"−, NTf_2"− and NfO"−. Toxicity evaluation on activated sludge of each compound (5% v/v of IL) was assessed by using a glucose uptake inhibition test. Toxicity against zebrafish and cytotoxicity were evaluated by the ImPACCell platform of Rennes (France). Fluoride release in water was estimated by regular measurements using ion chromatography equipment. IL biodegradability was determined by measuring BOD_2_8 of aqueous samples (compound concentration,1 mM). All ILs tested were not biodegradable; while some of them were toxic toward activated sludge. Isoquinolinium ILs were toxic to human cancerous cell lines. Nevertheless no toxicity was found against zebrafish Danio rerio. Only one IL released fluoride after long-time agitation.

Application of numerical modelling to scaling-up of electrically induced extraction from an organic mixture using an ionic liquid

Directory of Open Access Journals (Sweden)

Kamiński Kamil

2016-03-01

Full Text Available Liquid-liquid extraction provides an environmentally friendly process as an alternative to azeotropic distillation, pervaporation and reverse osmosis because these techniques require the use of large amounts of energy, may involve volatile organic compounds, and operation at high pressure.

Impact of Anaerobic Digestion of Liquid Dairy Manure on Ammonia Volatilization Process

Science.gov (United States)

Koirala, K.

2013-12-01

The goal of this study was to determine the effect of anaerobic digestion (AD) on the mechanism of ammonia volatilization from liquid dairy manure, in storage or treatment lagoon, prior to land application. Physical-chemical properties of liquid dairy manure, which may affect ammonia volatilization process, were determined before and after AD. The properties of interest included: particle size distribution (PSD), total solids (TS), volatile solids (VS), viscosity, pH, total ammoniacal nitrogen (TAN), and ionic strength (IS). The overall mass transfer coefficient of ammonia (KoL) and the NH3 fraction of TAN (β) for the undigested (UD) and AD manures were then experimentally determined in a laboratory convective emission chamber (CEC) at a constant wind speed of 1.5 m s-1 and fixed air temperature of 25 °C at liquid manure temperatures of 15, 25, and 35 °C. The PSD indicated non-normal left skewed distribution for both AD and UD manures particles, suggestive of heavier concentrations of particles towards the lower particle size range. The volume median diameters (VMD) for solids from UD and AD were not significantly different (p= 0.65), but the geometric standard deviations (GSD) were significantly different (p = 0.001), indicating slightly larger particles but more widely distributed solids in UD than AD manure. Results also indicated significantly higher pH, TAN, ionic strength (IS) and viscosity in AD manure. The KoL and β for AD manure determined under identical conditions (air temperature, liquid temperature, and airflow) were significantly higher (p > 0.05) than for UD manure. Overall, these findings suggest that AD of dairy manure significantly increased initial ammonia volatilization potential from liquid dairy manure; with the largest increase (~62%) emanating from increased ammonium dissociation. The initial flux of ammonia, during the experiment period, was ~84% more from AD than in UD dairy manure. Keywords. Process based models, mass transfer

Simultaneous biodegradation of volatile and toxic contaminant mixtures by solid–liquid two-phase partitioning bioreactors

Energy Technology Data Exchange (ETDEWEB)

Poleo, Eduardo E.; Daugulis, Andrew J., E-mail: andrew.daugulis@chee.queensu.ca

2013-06-15

Highlights: • We investigate the simultaneous biodegradation of phenol and butyl acetate. • We identify an effective polymer mixture to selectively absorb each of the substrates and decrease their initial concentration. •The polymer mixture is used to overcome the high phenol cytotoxicity and reduce the abiotic losses of butyl acetate associated with volatility. • The solid–liquid Two Phase Partitioning Bioreactor (TPPB) outperforms the liquid–liquid TPPB and the single phase systems. -- Abstract: Microbial inhibition and stripping of volatile compounds are two common problems encountered in the biotreatment of contaminated wastewaters. Both can be addressed by the addition of a hydrophobic auxiliary phase that can absorb and subsequently re-release the substrates, lowering their initial aqueous concentrations. Such systems have been described as Two Phase Partitioning Bioreactors (TPPBs). In the current work the performances of a solid–liquid TPPB, a liquid–liquid TPPB and a single phase reactor for the simultaneous degradation of butyl acetate (the volatile component) and phenol (the toxic component) have been compared. The auxiliary phase used in the solid–liquid TPPB was a 50:50 polymer mixture of styrene–butadiene rubber and Hytrel{sup ®} 8206, with high affinities for butyl acetate and phenol, respectively. The liquid–liquid TPPB employed silicone oil which has fixed physical properties, and had no capacity to absorb the toxic contaminant (phenol). Butyl acetate degradation was enhanced in both TPPBs relative to the single phase, arising from its sequestration into the auxiliary phase, thereby reducing volatilization losses. The solid–liquid TPPB additionally showed a substantial increase in the phenol degradation rate, relative to the silicone oil system, demonstrating the superiority and versatility of polymer based systems.

RESUS: A code for low volatile radio-nuclide release from liquids due to vapor bubble burst induced liquid jet formation and disintegration

International Nuclear Information System (INIS)

Koch, M.K.; Starflinger, J.; Linnemann, Th.; Brockmeier, U.; Unger, H.; Schuetz, W.

1995-01-01

In the field of nuclear safety, the release of volatile and low volatile radio-nuclides from liquid surfaces into a gas atmosphere is important for aerosol source term considerations particularly in late severe accident sequences. In case of a hypothetical nuclear reactor accident involving a failure of the primary system, primary coolant and radio-nuclides may be released into the containment to frequently form a liquid pool which may be contaminated by suspended or solved fuel particles and fission products. Under this scope, the release code package REVOLS/RENONS was developed for radio-nuclide release from liquid surfaces. Assuming the absence of gas or vapor bubbles in the liquid, the evaporative release of volatile components, calculated by the REVOLS code, is governed by diffusive and convective transport processes, whereas the release of low volatiles, calculated by the RENONS code, may be governed by mechanical processes which leads to droplet entrainment in case of wavy liquid pool surface conditions into the containment atmosphere by means of convection. For many accident sequences, in which gas is injected into a pool or liquid area elsewhere, predominantly when saturation temperatures can be reached, the release of low volatile species from liquid surfaces due to bubble burst is identified as a decisive release mechanism also. Together with the liquid, the particles which are located at the pool surface or suspended in the pool, are released into the atmosphere. Consequently, the code RESUS.MOD1 (RESUSpension) is presently extended to include the calculation of the release of droplets and suspended radio-nuclide particles due to bubble burst induced liquid jet formation and disintegration above liquid surfaces. Experimental investigations indicate the influence of bubble volume and shape at the pool surface as well as bubble stabilization or destabilization, and furthermore the system pressure and temperatures as well as fluid properties, on droplet

Methodology for the detection of contamination by hydrocarbons and further soil sampling for volatile and semi-volatile organic enrichment in former petrol stations, SE Spain

Directory of Open Access Journals (Sweden)

Rosa María Rosales Aranda

2012-01-01

Full Text Available The optimal detection and quantification of contamination plumes in soil and groundwater by petroleum organic compounds, gasoline and diesel, is critical for the reclamation of hydrocarbons contaminated soil at petrol stations. Through this study it has been achieved a sampling stage optimization in these scenarios by means of the location of potential contamination areas before sampling with the application of the 2D electrical resistivity tomography method, a geophysical non destructive technique based on resistivity measurements in soils. After the detection of hydrocarbons contaminated areas, boreholes with continuous coring were performed in a petrol station located in Murcia Region (Spain. The drillholes reached depths down to 10 m and soil samples were taken from each meter of the drilling. The optimization in the soil samples handling and storage, for both volatile and semi-volatile organic compounds determinations, was achieved by designing a soil sampler to minimize volatilization losses and in order to avoid the manual contact with the environmental samples during the sampling. The preservation of soil samples was performed according to Europe regulations and US Environmental Protection Agency recommendations into two kinds of glass vials. Moreover, it has been taken into account the determination techniques to quantify the hydrocarbon pollution based on Gas Chromatography with different detectors and headspace technique to reach a liquid-gas equilibrium for volatile analyses.

Synthesis and toxicity evaluation of hydrophobic ionic liquids for volatile organic compounds biodegradation in a two-phase partitioning bioreactor

Energy Technology Data Exchange (ETDEWEB)

Rodriguez Castillo, Alfredo Santiago [Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, 11 Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7 (France); Université européenne de Bretagne (France); Guihéneuf, Solène, E-mail: solene.guiheneuf@wanadoo.fr [Université européenne de Bretagne, Université de Rennes 1, Sciences Chimiques de Rennes, UMR, CNRS 6226, Groupe Ingénierie Chimique & Molécules Pour le Vivant (ICMV), Bât. 10A, Campus de Beaulieu, Avenue du Général Leclerc, CS 74205, 35042 Rennes cedex (France); Le Guével, Rémy [Plate-forme ImPACcell Structure Fédérative de Recherche BIOSIT Université de Rennes 1, Bat. 8, Campus de Villejean, 2 Avenue du Pr. Leon Bernard, CS 34317, 35043 Rennes Cedex (France); Biard, Pierre-François [Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, 11 Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7 (France); Université européenne de Bretagne (France); and others

2016-04-15

Highlights: • Description of a VOC depollution system suitable with industrial processes, TPPB. • Novel association of TPPB and hydrophobic ionic liquids. • Synthesis of several hydrophobic ionic liquids designed to fit desired properties. • Toxicity evaluation of these ILs towards cells, animals and bacteria. - Abstract: Synthesis of several hydrophobic ionic liquids (ILs), which might be selected as good candidates for degradation of hydrophobic volatile organic compounds in a two-phase partitioning bioreactor (TPPB), were carried out. Several bioassays were also realized, such as toxicity evaluation on activated sludge and zebrafish, cytotoxicity, fluoride release in aqueous phase and biodegradability in order to verify their possible effects in case of discharge in the aquatic environment and/or human contact during industrial manipulation. The synthesized compounds consist of alkylimidazoliums, functionalized imidazoliums, isoqinoliniums, triazoliums, sulfoniums, pyrrolidiniums and morpholiniums and various counter-ions such as: PF{sub 6}{sup −}, NTf{sub 2}{sup −} and NfO{sup −}. Toxicity evaluation on activated sludge of each compound (5% v/v of IL) was assessed by using a glucose uptake inhibition test. Toxicity against zebrafish and cytotoxicity were evaluated by the ImPACCell platform of Rennes (France). Fluoride release in water was estimated by regular measurements using ion chromatography equipment. IL biodegradability was determined by measuring BOD{sub 28} of aqueous samples (compound concentration,1 mM). All ILs tested were not biodegradable; while some of them were toxic toward activated sludge. Isoquinolinium ILs were toxic to human cancerous cell lines. Nevertheless no toxicity was found against zebrafish Danio rerio. Only one IL released fluoride after long-time agitation.

Effect of inorganic salts on the volatility of organic acids.

Science.gov (United States)

Häkkinen, Silja A K; McNeill, V Faye; Riipinen, Ilona

2014-12-02

Particulate phase reactions between organic and inorganic compounds may significantly alter aerosol chemical properties, for example, by suppressing particle volatility. Here, chemical processing upon drying of aerosols comprised of organic (acetic, oxalic, succinic, or citric) acid/monovalent inorganic salt mixtures was assessed by measuring the evaporation of the organic acid molecules from the mixture using a novel approach combining a chemical ionization mass spectrometer coupled with a heated flow tube inlet (TPD-CIMS) with kinetic model calculations. For reference, the volatility, i.e. saturation vapor pressure and vaporization enthalpy, of the pure succinic and oxalic acids was also determined and found to be in agreement with previous literature. Comparison between the kinetic model and experimental data suggests significant particle phase processing forming low-volatility material such as organic salts. The results were similar for both ammonium sulfate and sodium chloride mixtures, and relatively more processing was observed with low initial aerosol organic molar fractions. The magnitude of low-volatility organic material formation at an atmospherically relevant pH range indicates that the observed phenomenon is not only significant in laboratory conditions but is also of direct atmospheric relevance.

A reexamination of the relationship between volatility, liquidity and trading activity

Directory of Open Access Journals (Sweden)

Khine Kyaw

2013-03-01

Full Text Available Este trabajo investiga si la relación entre actividad negociadora en el mercado de acciones, la liquidez del mercado y la volatilidad a nivel de cartera, es similar a dicha relación a nivel deacciones individuales. Para las carteras de empresas de mayor tamaño, la mayor actividad negociadora está relacionada con mayor liquidez y más volatilidad. Sin embargo, a pesar de quela relación volatilidad-liquidez es la misma para las carteras de acciones pequeñas, encontramos que la mayor actividad negociadora está negativamente asociada con la liquidez para estaagrupación. Este contraste en las relaciones está causado por las interrelaciones dinámicas entre las tres variables y una vez que se controla por esas interrelaciones, dicho contraste en losresultados desparece. Estos hallazgos contribuyen al debate sobre el comportamiento del mercado, que ha adquirido un renovado interés en los últimos años.We investigate whether the relationship between equity trading activity, market liquidity and return volatility at the portfolio level is similar to the relationship at the individual security level. For the very largest firm-size portfolio, higher trading activity is positively associated with greater liquidity and more volatile returns. However, despite the volatility-liquidity relationship being the same for smaller equity portfolios, we find that higher trading activity is negatively associated with liquidity for this grouping. These contrasting relationships are shown to be caused by the interdynamics between all three variables and once we control for these interrelationships, the contrasting results disappear. The findings contribute to the debate on market behaviour that has taken on renewed vigour in recent years.

Organic and volatile elements in the solar system

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Remusat L.

2012-01-01

Full Text Available Chondrites and comets have accreted primitive materials from the early solar system. Those materials include organics, water and other volatile components. The most primitive chondrites and comets have undergone few modifications on their respective parent bodies and can deliver to laboratories components that were present at the origin of the protosolar nebula. Here I present a review of the organic material and volatile components that have been studied in the most primitive chondrites, and the last data from the stardust mission about the cometary record. This paper focuses on materials that can be studied in laboratories, by mass spectrometry, ion probes or organic chemistry techniques.

Effect of a cationic surfactant on the volatilization of PAHs from soil.

Science.gov (United States)

Lu, Li; Zhu, Lizhong

2012-06-01

Cationic surfactants are common in soils because of their use in daily cosmetic and cleaning products, and their use as a soil amendment for the mitigation and remediation of organic contaminated soils has been proposed. Such surfactant may affect the transfer and fate of organic contaminants in the environment. This study investigated the effect of a cationic surfactant, dodecylpyridinium bromide (DDPB), on the volatilization of polycyclic aromatic hydrocarbons (PAHs) from a paddy soil. The volatilization of PAHs from moist soil amended with different concentrations of DDPB was tested in an open system. The specific effects of DDPB on the liquid-vapor and solid-vapor equilibriums of PAHs were separately investigated in closed systems by headspace analysis. DDPB affects both liquid-vapor and solid-vapor processes of PAHs in soil. At DDPB concentrations below the critical micelle concentration (CMC), movement of PAHs from the bulk solution to the gas-liquid interface appeared to be facilitated by interaction between PAHs and the surfactant monomers adsorbed at the gas-liquid interface, promoting the volatilization of PAHs from solution. However, when DDPB was greater than the CMC, volatilization was inhibited due to the solubilization of PAHs by micelles. On the other hand, the formation of sorbed surfactant significantly inhibited the solid-vapor volatilization of PAHs. The overall effect of the two simultaneous effects of DDPB on liquid-vapor and solid-vapor processes was a decreased volatilization loss of PAHs from soil. Inhibition of PAH volatilization was more significant for the soil with a lower moisture content.

Levels and source apportionment of volatile organic compounds in southwestern area of Mexico City

Energy Technology Data Exchange (ETDEWEB)

Rodolfo Sosa, E. [Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Ciudad Universitaria, C.P. 04510, D.F. (Mexico); Humberto Bravo, A. [Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Ciudad Universitaria, C.P. 04510, D.F. (Mexico)], E-mail: hbravo@servidor.unam.mx; Violeta Mugica, A. [Universidad Autonoma Metropolitana, Azcapotzalco, D.F. (Mexico); Pablo Sanchez, A. [Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Ciudad Universitaria, C.P. 04510, D.F. (Mexico); Emma Bueno, L. [Centro Nacional de Investigacion y Capacitacion Ambiental, Instituto Nacional de Ecologia (Mexico); Krupa, Sagar [Department of Plant Pathology, University of Minnesota, St. Paul, MN 55108 (United States)

2009-03-15

Thirteen volatile organic compounds (VOCs) were quantified at three sites in southwestern Mexico City from July 2000 to February 2001. High concentrations of different VOCs were found at a Gasoline refueling station (GS), a Condominium area (CA), and at University Center for Atmospheric Sciences (CAS). The most abundant VOCs at CA and CAS were propane, n-butane, toluene, acetylene and pentane. In comparison, at GS the most abundant were toluene, pentane, propane, n-butane, and acetylene. Benzene, a known carcinogenic compound had average levels of 28, 35 and 250 ppbC at CAS, CA, and GS respectively. The main contributing sources of the measured VOCs at CA and CAS were the handling and management of LP (Liquid Propane) gas, vehicle exhaust, asphalt works, and use of solvents. At GS almost all of the VOCs came from vehicle exhaust and fuel evaporation, although components of LP gas were also present. Based on the overall results possible abatement strategies are discussed. - Volatile organic compounds were quantified in order to perform their source apportionment in southwestern area of Mexico City.

Levels and source apportionment of volatile organic compounds in southwestern area of Mexico City

International Nuclear Information System (INIS)

Rodolfo Sosa, E.; Humberto Bravo, A.; Violeta Mugica, A.; Pablo Sanchez, A.; Emma Bueno, L.; Krupa, Sagar

2009-01-01

Thirteen volatile organic compounds (VOCs) were quantified at three sites in southwestern Mexico City from July 2000 to February 2001. High concentrations of different VOCs were found at a Gasoline refueling station (GS), a Condominium area (CA), and at University Center for Atmospheric Sciences (CAS). The most abundant VOCs at CA and CAS were propane, n-butane, toluene, acetylene and pentane. In comparison, at GS the most abundant were toluene, pentane, propane, n-butane, and acetylene. Benzene, a known carcinogenic compound had average levels of 28, 35 and 250 ppbC at CAS, CA, and GS respectively. The main contributing sources of the measured VOCs at CA and CAS were the handling and management of LP (Liquid Propane) gas, vehicle exhaust, asphalt works, and use of solvents. At GS almost all of the VOCs came from vehicle exhaust and fuel evaporation, although components of LP gas were also present. Based on the overall results possible abatement strategies are discussed. - Volatile organic compounds were quantified in order to perform their source apportionment in southwestern area of Mexico City

Volatility of organic aerosol and its components in the Megacity of Paris

Science.gov (United States)

Paciga, A.; Karnezi, E.; Kostenidou, E.; Hildebrandt, L.; Psichoudaki, M.; Engelhart, G. J.; Lee, B.-H.; Crippa, M.; Prévôt, A. S. H.; Baltensperger, U.; Pandis, S. N.

2015-08-01

Using a mass transfer model and the volatility basis set, we estimate the volatility distribution for the organic aerosol (OA) components during summer and winter in Paris, France as part of the collaborative project MEGAPOLI. The concentrations of the OA components as a function of temperature were measured combining data from a thermodenuder and an aerosol mass spectrometer (AMS) with Positive Matrix Factorization (PMF) analysis. The hydrocarbon-like organic aerosol (HOA) had similar volatility distributions for the summer and winter campaigns with half of the material in the saturation concentration bin of 10 μg m-3 and another 35-40 % consisting of low and extremely low volatility organic compounds (LVOCs and ELVOCs, respectively). The winter cooking OA (COA) was more than an order of magnitude less volatile than the summer COA. The low volatility oxygenated OA (LV-OOA) factor detected in the summer had the lowest volatility of all the derived factors and consisted almost exclusively of ELVOCs. The volatility for the semi-volatile oxygenated OA (SV-OOA) was significantly higher than that of the LV-OOA, containing both semi-volatile organic components (SVOCs) and LVOCs. The oxygenated OA (OOA) factor in winter consisted of SVOCs (45 %), LVOCs (25 %) and ELVOCs (30 %). The volatility of marine OA (MOA) was higher than that of the other factors containing around 60 % SVOCs. The biomass burning OA (BBOA) factor contained components with a wide range of volatilities with significant contributions from both SVOCs (50 %) and LVOCs (30 %). Finally, combining the O : C ratio and volatility distributions of the various factors, we incorporated our results into the two-dimensional volatility basis set (2D-VBS). Our results show that the factors cover a broad spectrum of volatilities with no direct link between the average volatility and average O : C of the OA components. Agreement between our findings and previous publications is encouraging for our understanding of the

Enantiomeric distribution of major chiral volatile organic compounds in juniper-flavored distillates.

Science.gov (United States)

Pažitná, Alexandra; Spánik, Ivan

2014-02-01

The enantiomeric ratios of chiral volatile organic compounds in juniper-flavored spirits produced by various processing technologies in different EU countries were determined by multidimensional GC using solid-phase microextraction and liquid-liquid extraction as a sample pretreatment procedure. In total, more than 260 compounds were detected in studied spirits from which linalool, α-terpineol, 4-terpineol, linalool oxides, α-pinene, and verbenone were selected for enantiomeric separation. The significant differences in enantiomeric ratio of linalool and cis-linalool oxide allowed us to distinguish between samples produced in Slovakia and the United Kingdom from those produced in Germany, Czech Republic, and Belgium. The pure enantiomer of trans-linalool oxide was found only in samples from Germany. It was shown that the enantiomeric ratio is independent of the sample treatment procedure, and only small differences up to 1% were observed. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cation symmetry effect on the volatility of ionic liquids.

Science.gov (United States)

Rocha, Marisa A A; Coutinho, João A P; Santos, Luís M N B F

2012-09-06

This work reports the first data for the vapor pressures at several temperatures of the ionic liquids, [C(N/2)C(N/2)im][NTf(2)] (N = 4, 6, 8, 10, 12) measured using a Knudsen effusion apparatus combined with a quartz crystal microbalance. The morphology and the thermodynamic parameters of vaporization derived from the vapor pressures, are compared with those for the 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide series, [C(N-1)C(1)im][NTf(2)] (N = 3 - 9, 11, and 13). It was found that the volatility of [C(N/2)C(N/2)im][NTf(2)] series is significantly higher than the asymmetric cation ILs with the same total number of carbons in the alkyl side chains, [C(N-1)C(1)im][NTf(2)]. The observed higher volatility is related with the lower enthalpy of vaporization. The symmetric cation, [C(N/2)C(N/2)im][NTf(2)], presents lower entropies of vaporization compared with the asymmetric [C(N-1)C(1)im][NTf(2)], indicating an increase of the absolute liquid entropy in the symmetric cation ILs, being a reflection of a change of the ion dynamics in the IL liquid phase. Moreover both the enthalpy and entropy of vaporization of the [C(N/2)C(N/2)im][NTf(2)] ILs, present a clear odd-even effect with higher enthalpies/entropies of vaporization for the odd number of carbons in each alkyl chain ([C(3)C(3)im][NTf(2)] and [C(5)C(5)im][NTf(2)]).

Assessing the sensitivity of benzene cluster cation chemical ionization mass spectrometry toward a wide array of biogenic volatile organic compounds

Science.gov (United States)

Lavi, Avi; Vermeuel, Michael; Novak, Gordon; Bertram, Timothy

2017-04-01

Chemical ionization mass spectrometry is a real-time, sensitive and selective measurement technique for the detection of volatile organic compounds (VOCs). The benefits of CIMS technology make it highly suitable for field measurements that requires fast (10Hz and higher) response rates, such as the study of surface-atmosphere exchange processes by the eddy covariance method. The use of benzene cluster cations as a regent ion was previously demonstrated as a sensitive and selective method for the detection of select biogenic VOCs (e.g. isoprene, monoterpenes and sesquiterpenes) [Kim et al., 2016; Leibrock and Huey, 2000]. Quantitative analysis of atmospheric trace gases necessitates calibration for each analyte as a function of atmospheric conditions. We describe a custom designed calibration system, based on liquid evaporation, for determination of the sensitivity of the benzene-CIMS to a wide range of organic compounds at atmospherically relevant mixing ratios (volatile organic compounds, Atmos Meas Tech, 9(4), 1473-1484, doi:10.5194/amt-9-1473-2016. Leibrock, E., and L. G. Huey (2000), Ion chemistry for the detection of isoprene and other volatile organic compounds in ambient air, Geophys Res Lett, 27(12), 1719-1722, doi:Doi 10.1029/1999gl010804.

Production of fungal volatile organic compounds in bedding materials

OpenAIRE

S. LAPPALAINEN; A. PASANEN; P. PASANEN

2008-01-01

The high relative humidity of the air and many potential growth media, such as bedding materials, hay and grains in the horse stable, for example, provide suitable conditions for fungal growth. Metabolic activity of four common agricultural fungi incubated in peat and wood shavings at 25°C and 4°C was characterized in this study using previously specified volatile metabolites of micro-organisms and CO 2 production as indicators. The volatile organic compounds were collected into Tenax resin a...

Ionic liquid marbles.

Science.gov (United States)

Gao, Lichao; McCarthy, Thomas J

2007-10-09

Liquid marbles have been reported during this decade and have been argued to be potentially useful for microfluidic and lab-on-a-chip applications. The liquid marbles described to date have been composed of either water or glycerol as the liquid and hydrophobized lycopodium or silica as the stabilizing particles. Both of these components are potentially reactive and do not permit the use of organic chemistry; the liquids are volatile. We report the use of perfluoroalkyl particles (oligomeric (OTFE) and polymeric (PTFE) tetrafluoroethylene, which are unreactive) to support/stabilize a range of ionic liquid marbles. Ionic liquids are not volatile and have been demonstrated to be versatile solvents for chemical transformations. Water marbles prepared with OTFE are much more robust than those prepared with hydrophobized lycopodium or silica.

A dynamic two-dimensional system for measuring volatile organic compound volatilization and movement in soils.

Science.gov (United States)

Allaire, S E; Yates, S R; Ernst, F F; Gan, J

2002-01-01

There is an important need to develop instrumentation that allows better understanding of atmospheric emission of toxic volatile compounds associated with soil management. For this purpose, chemical movement and distribution in the soil profile should be simultaneously monitored with its volatilization. A two-dimensional rectangular soil column was constructed and a dynamic sequential volatilization flux chamber was attached to the top of the column. The flux chamber was connected through a manifold valve to a gas chromatograph (GC) for real-time concentration measurement. Gas distribution in the soil profile was sampled with gas-tight syringes at selected times and analyzed with a GC. A pressure transducer was connected to a scanivalve to automatically measure the pressure distribution in the gas phase of the soil profile. The system application was demonstrated by packing the column with a sandy loam in a symmetrical bed-furrow system. A 5-h furrow irrigation was started 24 h after the injection of a soil fumigant, propargyl bromide (3-bromo-1-propyne; 3BP). The experience showed the importance of measuring lateral volatilization variability, pressure distribution in the gas phase, chemical distribution between the different phases (liquid, gas, and sorbed), and the effect of irrigation on the volatilization. Gas movement, volatilization, water infiltration, and distribution of degradation product (Br-) were symmetric around the bed within 10%. The system saves labor cost and time. This versatile system can be modified and used to compare management practices, estimate concentration-time indexes for pest control, study chemical movement, degradation, and emissions, and test mathematical models.

Total volatile organic compounds (TVOC) in indoor air quality investigations

DEFF Research Database (Denmark)

Mølhave, L.; Clausen, Geo; Berglund, B.

1997-01-01

The amount of volatile organic compounds (VOCs) in indoor air, usually called TVOC (total volatile organic compounds), has been measured using different definitions and techniques which yield different results. This report recommends a definition of TVOC referring to a specified range of VOCs...... for characterizing indoor pollution and for improving source control as required from the points of view of health, comfort, energy efficiency and sustainability. (C) Indoor Air (1997)....

Inventory of volatile organic compound emissions in Finland, 1985

International Nuclear Information System (INIS)

Mroueh, U.M.

1988-01-01

The aim of the study was to compile an inventory of the emissions of volatile organic compounds in Finland for the year 1985. The report was prepared for the ECE Task Force on Emissions of Volatile Organic Compounds from Stationary Sources according to the classification given by the Task Force. It considers anthropogenic as well as natural sources. Mobile sources are excluded. The quantities as well as the main components are listed, as far as possible. The values given exclude methane which according to the present understanding is regarded as unreactive

Remediation of ground water containing volatile organic compounds and tritium

International Nuclear Information System (INIS)

Shukla, S.N.; Folsom, E.N.

1994-03-01

The Trailer 5475 (T-5475) East Taxi Strip Area at Lawrence Livermore National Laboratory (LLNL), Livermore, California was used as a taxi strip by the US Navy to taxi airplanes to the runway from 1942 to 1947. Solvents were used in some unpaved areas adjacent to the East Taxi Strip for cleaning airplanes. From 1953 through 1976, the area was used to store and treat liquid waste. From 1962 to 1976 ponds were constructed and used for evaporation of liquid waste. As a result, the ground water in this area contains volatile organic compounds (VOCs) and tritium. The ground water in this area is also known to contain hexavalent chromium that is probably naturally occurring. Therefore, LLNL has proposed ''pump-and-treat'' technology above grade in a completely closed loop system. The facility will be designed to remove the VOCs and hexavalent chromium, if any, from the ground water, and the treated ground water containing tritium will be reinjected where it will decay naturally in the subsurface. Ground water containing tritium will be reinjected into areas with equal or higher tritium concentrations to comply with California regulations

Biogenic volatile organic compounds in the Earth system.

Science.gov (United States)

Laothawornkitkul, Jullada; Taylor, Jane E; Paul, Nigel D; Hewitt, C Nicholas

2009-01-01

Biogenic volatile organic compounds produced by plants are involved in plant growth, development, reproduction and defence. They also function as communication media within plant communities, between plants and between plants and insects. Because of the high chemical reactivity of many of these compounds, coupled with their large mass emission rates from vegetation into the atmosphere, they have significant effects on the chemical composition and physical characteristics of the atmosphere. Hence, biogenic volatile organic compounds mediate the relationship between the biosphere and the atmosphere. Alteration of this relationship by anthropogenically driven changes to the environment, including global climate change, may perturb these interactions and may lead to adverse and hard-to-predict consequences for the Earth system.

Recent Advances in the Emission and Functions of Plant Vegetative Volatiles

Directory of Open Access Journals (Sweden)

Fang Dong

2016-01-01

Full Text Available Plants synthesize and emit a large variety of volatile organic compounds, which possess extremely important ecological functions. In most case, most plant volatiles are liquids, rather than gases, at room temperature. Some volatiles are emitted “on demand” when plants, especially vegetative parts, are exposed to abiotic or biotic stress. In this review, we summarize some of the highlights of plant vegetative volatile emission and functions research published during the past few years.

Comparison of two common adsorption materials for thermal desorption gas chromatography - mass spectrometry of biogenic volatile organic compounds.

Science.gov (United States)

Marcillo, Andrea; Jakimovska, Viktorija; Widdig, Anja; Birkemeyer, Claudia

2017-09-08

Volatile organic compounds (VOCs) are commonly collected from gaseous samples by adsorption to materials such as the porous polymer Tenax TA. Adsorbed compounds are subsequently released from these materials by thermal desorption (TD) and separated then by gas chromatography (GC) with flame ionization (FID) or mass spectrometry (MS) detection. Tenax TA is known to be particularly suitable for non-polar to semipolar volatiles, however, many volatiles from environmental and biological samples possess a rather polar character. Therefore, we tested if the polymer XAD-2, which so far is widely used to adsorb organic compounds from aqueous and organic solvents, could provide a broader coverage for (semi)polar VOCs during gas-phase sampling. Mixtures of volatile compounds covering a wide range of volatility (bp. 20-256°C) and different chemical classes were introduced by liquid spiking into sorbent tubes with one of the two porous polymers, Tenax TA or XAD-2, and analyzed by TD/GC-MS. At first, an internal standard mixture composed of 17 authentic standards was used to optimize desorption temperature with respect to sorbent degradation and loading time for calibration. Secondly, we tested the detectability of a complex standard mixture composed of 57 volatiles, most of them common constituents of the body odor of mammals. Moreover, the performance of XAD-2 compared with Tenax TA was assessed as limit of quantitation and linearity for the internal standard mixture and 33 compounds from the complex standard mixture. Volatiles were analyzed in a range between 0.01-∼250ng/tube depending on the compound and material. Lower limits of quantitation were between 0.01 and 3 ng±0.9). Interestingly, we found different kinetics for compound adsorption with XAD-2, and a partially better sensitivity in comparison with Tenax TA. For these analytes, XAD-2 might be recommended as an alternative of Tenax TA for TD/GC-MS analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

Novel 2-Alkyl-1-Ethylpyridinium ionic liquids : synthesis, dissociation energies and volatility

NARCIS (Netherlands)

Vilas, M.; Alves da Rocha, M.A.; Fernandes, A.M.; Tojo, E.; Santos, L.M.N.B.F.

2015-01-01

This work presents the synthesis, volatility study and electrospray ionization mass spectrometry with energy-variable collision induced dissociation of the isolated [(cation)2(anion)]+ of a novel series of 2-alkyl-1-ethyl pyridinium based ionic liquids, [2CN-21C2Py][NTf2]. Compared to the

Production of fungal volatile organic compounds in bedding materials

Directory of Open Access Journals (Sweden)

S. LAPPALAINEN

2008-12-01

Full Text Available The high relative humidity of the air and many potential growth media, such as bedding materials, hay and grains in the horse stable, for example, provide suitable conditions for fungal growth. Metabolic activity of four common agricultural fungi incubated in peat and wood shavings at 25°C and 4°C was characterized in this study using previously specified volatile metabolites of micro-organisms and CO 2 production as indicators. The volatile organic compounds were collected into Tenax resin and analysed by gas chromatography. Several microbial volatile organic compounds (MVOCs, e.g. 1-butanol, 2-hexanone, 2-heptanone, 3-octanone, 1-octen-3-ol and 1-octanol were detected in laboratory experiments; however, these accounted for only 0.08-1.5% of total volatile organic com-pounds (TVOCs. Emission rates of MVOCs were 0.001-0.176 mg/kg of bedding materials per hour. Despite some limitations of the analytical method, certain individual MVOCs, 2-hexanone, 2-hep-tanone and 3-octanone, were also detected in concentrations of less than 4.6 mg/m 3 (0.07-0.31% of TVOC in a horse stable where peat and shavings were used as bedding materials. MVOC emission rate was estimated to be 0.2-2.0 mg/kg ´ h -1 from bedding materials in the stable, being about ten times higher than the rates found in the laboratory experiments. Some compounds, e.g. 3-octanone and 1-octen-3-ol, can be assumed to originate mainly from microbial metabolisms.;

Quantitative estimates of the volatility of ambient organic aerosol

Science.gov (United States)

Cappa, C. D.; Jimenez, J. L.

2010-06-01

Measurements of the sensitivity of organic aerosol (OA, and its components) mass to changes in temperature were recently reported by Huffman et al.~(2009) using a tandem thermodenuder-aerosol mass spectrometer (TD-AMS) system in Mexico City and the Los Angeles area. Here, we use these measurements to derive quantitative estimates of aerosol volatility within the framework of absorptive partitioning theory using a kinetic model of aerosol evaporation in the TD. OA volatility distributions (or "basis-sets") are determined using several assumptions as to the enthalpy of vaporization (ΔHvap). We present two definitions of "non-volatile OA," one being a global and one a local definition. Based on these definitions, our analysis indicates that a substantial fraction of the organic aerosol is comprised of non-volatile components that will not evaporate under any atmospheric conditions; on the order of 50-80% when the most realistic ΔHvap assumptions are considered. The sensitivity of the total OA mass to dilution and ambient changes in temperature has been assessed for the various ΔHvap assumptions. The temperature sensitivity is relatively independent of the particular ΔHvap assumptions whereas dilution sensitivity is found to be greatest for the low (ΔHvap = 50 kJ/mol) and lowest for the high (ΔHvap = 150 kJ/mol) assumptions. This difference arises from the high ΔHvap assumptions yielding volatility distributions with a greater fraction of non-volatile material than the low ΔHvap assumptions. If the observations are fit using a 1 or 2-component model the sensitivity of the OA to dilution is unrealistically high. An empirical method introduced by Faulhaber et al. (2009) has also been used to independently estimate a volatility distribution for the ambient OA and is found to give results consistent with the high and variable ΔHvap assumptions. Our results also show that the amount of semivolatile gas-phase organics in equilibrium with the OA could range from ~20

Characteristics of the volatile organic compounds -- Arid Integrated Demonstration Site

International Nuclear Information System (INIS)

Last, G.V.; Lenhard, R.J.; Bjornstad, B.N.; Evans, J.C.; Roberson, K.R.; Spane, F.A.; Amonette, J.E.; Rockhold, M.L.

1991-10-01

The Volatile Organic Compounds -- Arid Integrated Demonstration Program (VOC-Arid ID) is targeted at demonstration and testing of technologies for the evaluation and cleanup of volatile organic compounds and associated contaminants at arid DOE sites. The initial demonstration site is an area of carbon tetrachloride (CCl 4 ) contamination located near the center of the Hanford Site. The movement of CCl 4 and other volatile organic contaminants in the subsurface is very complex. The problem at the Hanford Site is further complicated by the concurrent discharge of other waste constituents including acids, lard oil, organic phosphates, and transuranic radionuclides. In addition, the subsurface environment is very complex, with large spatial variabilities in hydraulic properties. A thorough understanding of the problem is essential to the selection of appropriate containment, retrieval, and/or in situ remedial technologies. The effectiveness of remedial technologies depends on knowing where the contaminants are, how they are held up in a given physical and chemical subsurface environment; and knowing the physical, chemical, and microbiological changes that are induced by the various remedial technologies

A new high-speed hollow fiber based liquid phase microextraction method using volatile organic solvent for determination of aromatic amines in environmental water samples prior to high-performance liquid chromatography.

Science.gov (United States)

Sarafraz-Yazdi, A; Mofazzeli, F; Es'haghi, Z

2009-07-15

A new and fast hollow fiber based liquid phase microextraction (HF-LPME) method using volatile organic solvents coupled with high-performance liquid chromatography (HPLC) was developed for determination of aromatic amines in the environmental water samples. Analytes including 3-nitroaniline, 3-chloroaniline and 4-bromoaniline were extracted from 6 mL basic aqueous sample solution (donor phase, NaOH 1 mol L(-1)) into the thin film of organic solvent that surrounded and impregnated the pores of the polypropylene hollow fiber wall (toluene, 20 microL), then back-extracted into the 6 mL acidified aqueous solution (acceptor phase, HCl 0.5 mol L(-1)) in the lumen of the two-end sealed hollow fiber. After the extraction, 5 microL of the acceptor phase was withdrawn into the syringe and injected directly into the HPLC system for the analysis. The parameters influencing the extraction efficiency including the kind of organic solvent and its volume, composition of donor and acceptor phases and the volume ratio between them, extraction time, stirring rate, salt addition and the effect of the analyte complexation with 18-crown-6 ether were investigated and optimized. Under the optimal conditions (donor phase: 6 mL of 1 mol L(-1) NaOH with 10% NaCl; organic phase: 20 microL of toluene; acceptor phase: 6 microL of 0.5 mol L(-1) HCl and 600 mmol L(-1) 18-crown-6 ether; pre-extraction and back-extraction times: 75 s and 10 min, respectively; stirring rate: 800 rpm), the obtained EFs were between 259 and 674, dynamic linear ranges were 0.1-1000 microg L(-1) (R>0.9991), and also the limits of detection were in the range of 0.01-0.1 micro gL(-1). The proposed procedure worked very well for real environmental water samples with microgram per liter level of the analytes, and good relative recoveries (91-102%) were obtained for the spiked sample solutions.

Assessment of volatile organic emissions from a petroleum refinery land treatment site

International Nuclear Information System (INIS)

Wetherold, R.G.; Eklund, B.M.; Blaney, B.J.; Throneloe, S.A.

1990-01-01

This paper reports on a field assessment performed to measure the emissions of volatile organics from a petroleum refinery land treatment site. As part of this study, the emissions of total volatile organics from surface-applied and subsurface-injected oily sludge were measured over a 5-week period. The effect of soil tilling on the emissions also was monitored. Volatile organics emission rates were measured using the emission isolation flex chamber method. Soil samples were collected during the test periods to determine soil properties, oil levels and microbe count. Soil surface and ambient temperatures, both inside and outside the flux chambers, were measured throughout the test periods

Effect of sugars on liquid-vapour partition of volatile compounds in ready-to-drink coffee beverages.

Science.gov (United States)

Piccone, P; Lonzarich, V; Navarini, L; Fusella, G; Pittia, P

2012-09-01

The effect of sugars (sucrose, lactose, glucose, fructose, 10%w/v) on the liquid-vapour partition of selected volatile compounds of coffee beverages has been investigated in espresso coffee and ready-to-drink (RTD) canned coffee prepared and obtained by using the same Arabica roasted coffee beans blend. Aroma composition of coffee beverages has been preliminary investigated by headspace-gas chromatography (HS-GC) and solid phase microextraction-HS-GC-mass spectrometry to characterize the volatile pattern of the systems and to evaluate the effects of sugars on the aroma release/retention. Then, the liquid-vapour partition coefficient (k) of 4 selected key aroma compounds (diacetyl, 2,3-pentanedione, ethylpyrazine, hexanal) was determined in water, sugars solutions as well as RTD coffee brews added with the same sugars (10%w/v). Sugars added in coffee beverages affected the release of the volatiles and thus its aroma profile with differences due to the type of added sugar and coffee brew type. The k values of the selected volatile compounds resulted different depending on the model system composition (water, coffee brew) and sugar type added. In particular, melanoidins as well as other non-volatile components (lipids, acids, carbohydrates) in the RTD coffee brews could be implied in the change of k of the volatile compounds in respect to that observed in water. The effects of the sugar type on the release/retention of the four key coffee aroma compounds were partly explained in terms of 'salting out' especially for the more polar volatile compounds and in the sucrose-added model systems. The change of chemical and physico-chemical properties of the water and brews induced by the sugars as well as the occurrence of interactions between volatile compounds and non-volatile components may be implied in the reduction of the vapour partition of the aroma compounds. Copyright © 2012 John Wiley & Sons, Ltd.

Ionic liquid electrolytes for dye-sensitized solar cells.

Science.gov (United States)

Gorlov, Mikhail; Kloo, Lars

2008-05-28

The potential of room-temperature molten salts (ionic liquids) as solvents for electrolytes for dye-sensitized solar cells has been investigated during the last decade. The non-volatility, good solvent properties and high electrochemical stability of ionic liquids make them attractive solvents in contrast to volatile organic solvents. Despite this, the relatively high viscosity of ionic liquids leads to mass-transport limitations. Here we review recent developments in the application of different ionic liquids as solvents or components of liquid and quasi-solid electrolytes for dye-sensitized solar cells.

MATRIX-VBS (v1.0): Implementing an Evolving Organic Aerosol Volatility in an Aerosol Microphysics Model

Science.gov (United States)

Gao, Chloe Y.; Tsigaridis, Kostas; Bauer, Susanne E.

2017-01-01

The gas-particle partitioning and chemical aging of semi-volatile organic aerosol are presented in a newly developed box model scheme, where its effect on the growth, composition, and mixing state of particles is examined. The volatility-basis set (VBS) framework is implemented into the aerosol microphysical scheme MATRIX (Multiconfiguration Aerosol TRacker of mIXing state), which resolves mass and number aerosol concentrations and in multiple mixing-state classes. The new scheme, MATRIX-VBS, has the potential to significantly advance the representation of organic aerosols in Earth system models by improving upon the conventional representation as non-volatile particulate organic matter, often also with an assumed fixed size distribution. We present results from idealized cases representing Beijing, Mexico City, a Finnish forest, and a southeastern US forest, and investigate the evolution of mass concentrations and volatility distributions for organic species across the gas and particle phases, as well as assessing their mixing state among aerosol populations. Emitted semi-volatile primary organic aerosols evaporate almost completely in the intermediate-volatility range, while they remain in the particle phase in the low-volatility range. Their volatility distribution at any point in time depends on the applied emission factors, oxidation by OH radicals, and temperature. We also compare against parallel simulations with the original scheme, which represented only the particulate and non-volatile component of the organic aerosol, examining how differently the condensed-phase organic matter is distributed across the mixing states in the model. The results demonstrate the importance of representing organic aerosol as a semi-volatile aerosol, and explicitly calculating the partitioning of organic species between the gas and particulate phases.

Volatility of source apportioned wintertime organic aerosol in the city of Athens

Science.gov (United States)

Louvaris, Evangelos E.; Florou, Kalliopi; Karnezi, Eleni; Papanastasiou, Dimitrios K.; Gkatzelis, Georgios I.; Pandis, Spyros N.

2017-06-01

The volatility distribution of ambient organic aerosol (OA) and its components was measured during the winter of 2013 in the city of Athens combining a thermodenuder (TD) and a High Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS). Positive Matrix Factorization (PMF) analysis of both the ambient and the thermodenuder AMS-spectra resulted in a four-factor solution for the OA, namely: hydrocarbon-like OA (HOA), biomass burning OA (BBOA), cooking OA (COA), and oxygenated OA (OOA). The thermograms of the four factors were analyzed and the corresponding volatility distributions were estimated using the volatility basis set (VBS). All four factors included compounds with a wide range of effective volatilities from 10 to less than 10-4 μg m-3 at 298 K. Almost 40% of the HOA consisted of low-volatility organic compounds (LVOCs) with the semi-volatile compounds (SVOCs) representing roughly 30%, while the remaining 30% consisted of extremely low volatility organic compounds (ELVOCs). BBOA was more volatile than the HOA factor on average, with 10% ELVOCs, 40% LVOCs, and 50% SVOCs. 10% of the COA consisted of ELVOCs, another 65% LVOCs, and 50% SVOCs. Finally, the OOA was the least volatile factor and included 40% ELVOCs, 25% LVOCs, and 35% SVOCs. Combining the volatility distributions and the O:C ratios of the various factors, we placed our results in the 2D-VBS analysis framework of Donahue et al. (2012). HOA and BBOA are in the expected region but also include an ELVOC component. COA is in similar range as HOA, but on average is half an order of magnitude more volatile. The OOA in these wintertime conditions had a moderate O:C ratio and included both semi-volatile and extremely low volatility components. The above results are sensitive to the assumed values of the effective vaporization enthalpy and the accommodation coefficient. A reduction of the accommodation coefficient by an order of magnitude or the reduction of the vaporization enthalpy by 20 kJ mol-1

Volatile organic compounds

International Nuclear Information System (INIS)

Silseth, May Liss

1998-01-01

The goal is: Not more emission of volatile organic compounds (VOCs) than necessary. The items discussed in this presentation are the VOCs, how to calculate emission of VOCs, how to reduce or avoid them, and different recovery processes. The largest source of Norwegian emissions of non methane VOCs (NMVOCs) is offshore loading of raw petroleum. Emissions of VOCs should be reduced mainly for two reasons: (1) on sunny days NMVOCs may react with NOx to form ozon and smog close to the surface, (2) ozone and smog close to the surface may be harmful to plants and animals, and they are hazardous to human health. As for the calculation of VOC emissions, the VOCON project will release the calculation program HCGASS in 1999. This project is a cooperative project headed by SINTEF/Marintek

Acid digestion of organic liquids

International Nuclear Information System (INIS)

Partridge, J.A.; Bosuego, G.P.

1980-10-01

Laboratory studies on the destruction of liquid organic wastes by acid digestion are discussed. A variety of liquid waste types was tested, including those encountered in the nuclear industry as well as some organic liquids representative of non-nuclear industrial wastes. The liquids tested were vacuum pump oil, tri-n-butyl phosphate (TBP), normal paraffin hydrocarbon solvent (NPH), a mixture of 30 vol% TBP in NPH, carbon tetrachloride (CCl 4 ), trichloroethane, toluene, hexone (methyl isobutyl ketone), a mixture of hexone and NPH, polychlorobiphenyl (PCB), isopropanol, normal-decane, and two waste organic solutions from Hanford radioactive waste tanks. The tests demonstrated that several types of organic liquids can be destroyed by the acid digestion process. 8 figures, 19 tables

Environment and Pollution Management of Pollution Volatile Organic Compounds in Cluj-Napoca

Directory of Open Access Journals (Sweden)

Carmen Florean

2016-10-01

Full Text Available Pollution negative influences the environmental, human health, buildings and increase the production of waste. We are currently witnessing pollution and degradation in some cases irreversible, of the environment. Environmental issues are extremely complex and cover all sectors. Worldwide, industrial pollution strategies necessary to reduce emissions to the atmosphere hydrocarbons, volatile organic compounds (VOCs and other polluants in urban areas. The highest concentrations of volatile organic compounds of more than 80 mg/m3 occur in densely populated areas. The latest data reported in the residential area of Cluj-Napoca values did not exceed 20 m /m3. However peaks reported VOC concentrations, depending on the season, exceeding the upper limit that according to Law. 104/2011 is 75 μ/m3. It was identified due to increase annual mean concentration of VOCs as, in particular, road traffic exceeding sanitary standards on the main traffic routes within the city. In this paper the results obtained after carrying out an analysis of the average VOC concentration recorded in the city Cluj-Napoca as a result of car traffic. They were pursued average concentrations of VOCs resulting from the combustion of liquid fuels, petrol and diesel type. Analyzing the results obtained are proposed solutions for reducing VOC emissions. The rule under which these solutions have been proposed to reduce the concentration of VOCs took into account the possibility implementation and maintenance costs thereof.

A volatile fluid assisted thermo-pneumatic liquid metal energy harvester

Energy Technology Data Exchange (ETDEWEB)

Tang, Jianbo, E-mail: zhouyuan@mail.ipc.ac.cn, E-mail: jianbotang@mail.ipc.ac.cn [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Wang, Junjie; Liu, Jing; Zhou, Yuan, E-mail: zhouyuan@mail.ipc.ac.cn, E-mail: jianbotang@mail.ipc.ac.cn [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China)

2016-01-11

A close-cycle self-driving thermal energy harvester using liquid metal as energy carrier fluid has been proposed. The driving force that pushes the liquid metal against flow resistance and gravity is provided by a resistively heated volatile fluid based on thermo-pneumatic principle. The tested harvester prototype demonstrated its capability to extract thermal energy between small temperature gradient, at a scale of 10 °C. During a 5-h operation, it further demonstrated robust liquid metal recirculating performance at a time-average volume flow rate of 14 ml/min with a 12.25 W heating load. The prototype also managed to self-adjust to variable working conditions which indicated the reliability of this method. Advantages of this method include simple-structural design, rigid-motion free operation, and low-temperature actuation. These advantages make it uniquely suited for solar energy and low-grade heat harvesting, high heat flux electronics cooling, as well as autonomous machines actuating.

Volatile organic compound (VOC) determination in working atmospheres; Determinacion de compuestos organicos volatiles (VOC) en ambiente laboral

Energy Technology Data Exchange (ETDEWEB)

Blass A, Georgina; Panama T, Luz A; Corrales C, Deyanira [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

2003-07-01

The present work describes, in a synthesized way, the implementation and application of procedures based on the normativity related to the subject of the volatile organic compounds (Volatile Organic Compounds VOC), that allow to sample, quantify and evaluate the present contamination in the working atmosphere of a refinery due to the fugitive emissions of VOC and other substances. In accordance with the corresponding normativity, more than 189 organic compounds denominated dangerous air polluting agents (Hazardous Air Pollutants, HAP) can be found in a working atmosphere, but they are the 11 main HAP that can be found in a refinery. In the present article the work made for the sampling and quantification of 5 of the 11 dangerous polluting agents of the air: benzene, toluene, xylene, iso-octane and naphthalene. [Spanish] El presente trabajo describe, de manera sintetizada, la implementacion y aplicacion de procedimientos basados en la normatividad relacionada al tema de los compuestos organicos volatiles (Volatil Organic Compounds, VOC), que permiten muestrear, cuantificar y evaluar la contaminacion presente en el ambiente laboral de una refineria debido a las emisiones fugitivas de VOC y otras sustancias. De acuerdo con la normatividad correspondiente, mas de 189 compuestos organicos denominados contaminantes peligrosos del aire (Hazardous Air Pollutants, HAP), pueden ser encontrados en un ambiente laboral, pero son 11 los principales HAP que pueden ser hallados en una refineria. En el presente articulo se informa el trabajo realizado para el muestreo y cuantificacion de 5 de los 11 contaminantes peligrosos del aire: benceno, tolueno, xileno, iso-octano y naftaleno.

Volatile organic compounds and oxides of nitrogen. Further emission reductions

Energy Technology Data Exchange (ETDEWEB)

Froste, H [comp.

1997-12-31

This report presents the current status in relation to achievement of the Swedish Environmental target set by Parliament to reduce emission of volatile organic compounds by 50 per cent between 1988 and 2000. It also instructed the Agency to formulate proposed measures to achieve a 50 per cent reduction of emission of nitrogen oxides between 1985 and 2005. The report presents an overall account of emission trends for volatile organic compounds (from all sectors) and nitrogen oxides (from the industry sector) and steps proposed to achieve further emission reductions. 43 refs

Volatile organic compounds and oxides of nitrogen. Further emission reductions

Energy Technology Data Exchange (ETDEWEB)

Froste, H. [comp.

1996-12-31

This report presents the current status in relation to achievement of the Swedish Environmental target set by Parliament to reduce emission of volatile organic compounds by 50 per cent between 1988 and 2000. It also instructed the Agency to formulate proposed measures to achieve a 50 per cent reduction of emission of nitrogen oxides between 1985 and 2005. The report presents an overall account of emission trends for volatile organic compounds (from all sectors) and nitrogen oxides (from the industry sector) and steps proposed to achieve further emission reductions. 43 refs

Diffusivity measurements of volatile organics in levitated viscous aerosol particles

Directory of Open Access Journals (Sweden)

S. Bastelberger

2017-07-01

Full Text Available Field measurements indicating that atmospheric secondary organic aerosol (SOA particles can be present in a highly viscous, glassy state have spurred numerous studies addressing low diffusivities of water in glassy aerosols. The focus of these studies is on kinetic limitations of hygroscopic growth and the plasticizing effect of water. In contrast, much less is known about diffusion limitations of organic molecules and oxidants in viscous matrices. These may affect atmospheric chemistry and gas–particle partitioning of complex mixtures with constituents of different volatility. In this study, we quantify the diffusivity of a volatile organic in a viscous matrix. Evaporation of single particles generated from an aqueous solution of sucrose and small amounts of volatile tetraethylene glycol (PEG-4 is investigated in an electrodynamic balance at controlled relative humidity (RH and temperature. The evaporative loss of PEG-4 as determined by Mie resonance spectroscopy is used in conjunction with a radially resolved diffusion model to retrieve translational diffusion coefficients of PEG-4. Comparison of the experimentally derived diffusivities with viscosity estimates for the ternary system reveals a breakdown of the Stokes–Einstein relationship, which has often been invoked to infer diffusivity from viscosity. The evaporation of PEG-4 shows pronounced RH and temperature dependencies and is severely depressed for RH ≲ 30 %, corresponding to diffusivities < 10−14 cm2 s−1 at temperatures < 15 °C. The temperature dependence is strong, suggesting a diffusion activation energy of about 300 kJ mol−1. We conclude that atmospheric volatile organic compounds can be subject to severe diffusion limitations in viscous organic aerosol particles. This may enable an important long-range transport mechanism for organic material, including pollutant molecules such as polycyclic aromatic hydrocarbons (PAHs.

Immobilization of organic liquid wastes

International Nuclear Information System (INIS)

Greenhalgh, W.O.

1985-01-01

This report describes a portland cement immobilization process for the disposal treatment of radioactive organic liquid wastes which would be generated in a a FFTF fuels reprocessing line. An incineration system already on-hand was determined to be too costly to operate for the 100 to 400 gallons per year organic liquid. Organic test liquids were dispersed into an aqueous phosphate liquid using an emulsifier. A total of 109 gallons of potential and radioactive aqueous immiscible organic liquid wastes from Hanford 300 Area operations were solidified with portland cement and disposed of as solid waste during a 3-month test program with in-drum mixers. Waste packing efficiencies varied from 32 to 40% and included pump oils, mineral spirits, and TBP-NPH type solvents

Quantitative estimates of the volatility of ambient organic aerosol

Directory of Open Access Journals (Sweden)

C. D. Cappa

2010-06-01

Full Text Available Measurements of the sensitivity of organic aerosol (OA, and its components mass to changes in temperature were recently reported by Huffman et al.~(2009 using a tandem thermodenuder-aerosol mass spectrometer (TD-AMS system in Mexico City and the Los Angeles area. Here, we use these measurements to derive quantitative estimates of aerosol volatility within the framework of absorptive partitioning theory using a kinetic model of aerosol evaporation in the TD. OA volatility distributions (or "basis-sets" are determined using several assumptions as to the enthalpy of vaporization (ΔH_vap. We present two definitions of "non-volatile OA," one being a global and one a local definition. Based on these definitions, our analysis indicates that a substantial fraction of the organic aerosol is comprised of non-volatile components that will not evaporate under any atmospheric conditions; on the order of 50–80% when the most realistic ΔH_vap assumptions are considered. The sensitivity of the total OA mass to dilution and ambient changes in temperature has been assessed for the various ΔH_vap assumptions. The temperature sensitivity is relatively independent of the particular ΔH_vap assumptions whereas dilution sensitivity is found to be greatest for the low (ΔH_vap = 50 kJ/mol and lowest for the high (ΔH_vap = 150 kJ/mol assumptions. This difference arises from the high ΔH_vap assumptions yielding volatility distributions with a greater fraction of non-volatile material than the low ΔH_vap assumptions. If the observations are fit using a 1 or 2-component model the sensitivity of the OA to dilution is unrealistically high. An empirical method introduced by Faulhaber et al. (2009 has also been used to independently estimate a volatility distribution for the ambient OA and is found to give results consistent with the

The liquid organization of volunteer tourism

DEFF Research Database (Denmark)

Steele, Jessica; Dredge, Dianne

2017-01-01

Drawing from developments in sociology and organizational studies, this paper argues for a new understanding of volunteer tourism as liquid organization. It aims to explore the organization of volunteer tourism using a liquid organization perspective and to better understand the potential...... implications of this liquidity on the responsibility of volunteer tourism organizations to host com- munities. The analysis is based on data collected from 80 volunteer tourism organizations. The findings reveal that the volunteer tourism organizations show characteristics of liquid organiza- tion to varying...... degrees. The significance of the research is to problematize the way in which the institutional characteristics of volunteer tourism are (not) conceptualized in current literature and to introduce liquid organization as a means of reinvigorating debate about responsibility....

The liquid organization of volunteer tourism:

DEFF Research Database (Denmark)

Steele, Jessica; Dredge, Dianne

2017-01-01

Drawing from developments in sociology and organizational studies, this paper argues for a new understanding of volunteer tourism as liquid organization. It aims to explore the organization of volunteer tourism using a liquid organization perspective and to better understand the potential...... implications of this liquidity on the responsibility of volunteer tourism organizations to host com- munities. The analysis is based on data collected from 80 volunteer tourism organizations. The findings reveal that the volunteer tourism organizations show characteristics of liquid organiza- tion to varying...... degrees. The significance of the research is to problematize the way in which the institutional characteristics of volunteer tourism are (not) conceptualized in current literature and to introduce liquid organization as a means of reinvigorating debate about responsibility....

A volatile organics concentrator for use in monitoring Space Station water quality

Science.gov (United States)

Ehntholt, Daniel J.; Bodek, Itamar; Valentine, James R.; Trabanino, Rudy; Vincze, Johanna E.; Sauer, Richard L.

1990-01-01

The process used to identify, select, and design an approach to the isolation and concentration of volatile organic compounds from a water sample prior to chemical analysis in a microgravity environment is discerned. The trade analysis leading to the recommended volatile organics concentrator (VOC) concept to be tested in a breadboard device is presented. The system covers the areas of gases, volatile separation from water, and water removal/gas chromatograph/mass spectrometer interface. Five options for potential use in the VOC and GC/MS system are identified and ranked, and also nine options are presented for separation of volatiles from the water phase. Seven options for use in the water removal/GC column and MS interface are also identified and included in the overall considerations. A final overall recommendation for breadboard VOC testing is given.

Nitrate radicals and biogenic volatile organic compounds: oxidation, mechanisms, and organic aerosol

Science.gov (United States)

Oxidation of biogenic volatile organic compounds (BVOC) by the nitrate radical (NO3) represents one of the important interactions between anthropogenic emissions related to combustion and natural emissions from the biosphere. This interaction has been recognized for more than 3 d...

Volatile organic compounds in emissions from brown-coal-fired residential stoves

International Nuclear Information System (INIS)

Engewald, W.; Knobloch, T.; Efer, J.

1993-01-01

Volatile organic compounds were determined in stack-gas emissions from the residential burning of brown-coal briquets using adsorptive enrichment on hydrophobic adsorbents, thermal desorption and capillary-gas chromatographic analysis. 152 compounds were identified and quantified. Quantitative emission factors of the identified individual compounds were determined in relation to the amount of the fuel used. These factors permit assessment of the pollution of the city of Leipzig with volatile organic compounds resulting from the burning of indigenous lignite. (orig.) [de

Can clouds enhance long-range transport of low volatile, ionizable and surface-active chemicals?

DEFF Research Database (Denmark)

Franco, Antonio; Trapp, Stefan

2011-01-01

Atmospheric partitioning and transport of low volatile organic compounds is strongly influenced by the presence of water (e.g. clouds) and its deposition velocity (e.g. rainfall, snow). It was identified that the assumption of continuous rainfall underestimates the residence time and the transport....... The longer residence time predicted for some compounds in the LMT is due to the capacity of clouds to sorb non-volatile molecules in the liquid water and at the interface of cloud droplets. The efficiency of wet deposition to remove low volatile organic pollutants from the atmosphere is limited primarily...

Removal of volatile organic compounds by a high pressure microwave plasma torch

International Nuclear Information System (INIS)

Rubio, S.J.; Quintero, M.C.; Rodero, A.; Alvarez, R.

2004-01-01

A helium microwave plasma torch was studied and optimised as a destruction system of volatile organic compounds. Attention was focused on trichloroethylene as a prototypical volatile organic compound, which is used technologically and which poses known health risks. The dependence of the destruction efficiency on the plasma conditions was obtained for different values of trichloroethylene concentrations. The results show a destruction and removal efficiency greater than 99.999% (Authors)

Distribution of volatile organic compounds over a semiconductor Industrial Park in Taiwan.

Science.gov (United States)

Chiu, Kong-Hwa; Wu, Ben-Zen; Chang, Chih-Chung; Sree, Usha; Lo, Jiunn-Guang

2005-02-15

This study examined volatile organic compounds (VOC) concentration in ambient air collected during the years 2000--2003 at several different locations of Hsinchu Science-based Industrial Park (HSIP) in Taiwan. A canister automated GC-MS system analyzed the volatile organics in ambient air grasp samples according to T0-15 method. Oxygenated volatiles were the most abundant VOC detected in HSIP followed by aromatics that are commonly used as solvents in the semiconductor industries. The major components measured in the ambient air are 2-propanol (29-135 ppbv), acetone (12-164 ppbv), benzene (0.7-1.7 ppbv), and toluene (13-20 ppbv). At some of the sampling locations, odorous compounds such as carbon disulfide and dimethyl sulfide levels exceed threshold values. The estimated toluene/benzene ratio is very high at most of the sites. However, the total amount of VOC is reduced over the years from 2000 to 2003 due to strict implementation on use and discharge of solvents in industries. There exists no definite seasonal pattern for sporadic occurrence of high levels of some of the volatile organics. Stagnant weather conditions with low wind speeds aid accumulation of toxic species at ground level. The results entail that hi-tech semiconductor industries are still a potential source for harmful organic substances to surrounding microenvironment.

A large source of low-volatility secondary organic aerosol

DEFF Research Database (Denmark)

Ehn, Mikael; Thornton, Joel A.; Kleist, Einhard

2014-01-01

radiation and by acting as cloud condensation nuclei. The quantitative assessment of such climate effects remains hampered by a number of factors, including an incomplete understanding of how biogenic VOCs contribute to the formation of atmospheric secondary organic aerosol. The growth of newly formed...... particles from sizes of less than three nanometres up to the sizes of cloud condensation nuclei (about one hundred nanometres) in many continental ecosystems requires abundant, essentially non-volatile organic vapours, but the sources and compositions of such vapours remain unknown. Here we investigate...... the oxidation of VOCs, in particular the terpene α-pinene, under atmospherically relevant conditions in chamber experiments. We find that a direct pathway leads from several biogenic VOCs, such as monoterpenes, to the formation of large amounts of extremely low-volatility vapours. These vapours form...

Chemically-resolved volatility measurements of organic aerosol fom different sources.

Science.gov (United States)

Huffman, J A; Docherty, K S; Mohr, C; Cubison, M J; Ulbrich, I M; Ziemann, P J; Onasch, T B; Jimenez, J L

2009-07-15

A newly modified fast temperature-stepping thermodenuder (TD) was coupled to a High Resolution Time-of-Flight Aerosol Mass Spectrometer for rapid determination of chemically resolved volatility of organic aerosols (OA) emitted from individual sources. The TD-AMS system was used to characterize primary OA (POA) from biomass burning, trash burning surrogates (paper and plastic), and meat cooking as well as chamber-generated secondary OA (SOA) from alpha-pinene and gasoline vapor. Almost all atmospheric models represent POA as nonvolatile, with no allowance for evaporation upon heating or dilution, or condensation upon cooling. Our results indicate that all OAs observed show semivolatile behavior and that most POAs characterized here were at least as volatile as SOA measured in urban environments. Biomass-burning OA (BBOA) exhibited a wide range of volatilities, but more often showed volatility similar to urban OA. Paper-burning resembles some types of BBOA because of its relatively high volatility and intermediate atomic oxygen-to-carbon (O/C) ratio, while meat-cooking OAs (MCOA) have consistently lower volatility than ambient OA. Chamber-generated SOA under the relatively high concentrations used intraditional experiments was significantly more volatile than urban SOA, challenging extrapolation of traditional laboratory volatility measurements to the atmosphere. Most OAs sampled show increasing O/C ratio and decreasing H/C (hydrogen-to-carbon) ratio with temperature, further indicating that more oxygenated OA components are typically less volatile. Future experiments should systematically explore a wider range of mass concentrations to more fully characterize the volatility distributions of these OAs.

78 FR 29032 - Approval and Promulgation of Implementation Plans Tennessee: Revisions to Volatile Organic...

Science.gov (United States)

2013-05-17

... of the term ``particulate matter emissions'' at 1200-03-09-.01(4)(b)47 (vi) as part of the definition... Promulgation of Implementation Plans Tennessee: Revisions to Volatile Organic Compound Definition AGENCY..., 1999, SIP adds 17 compounds to the list of compounds excluded from the definition of ``Volatile Organic...

TMVOC, simulator for multiple volatile organic chemicals

International Nuclear Information System (INIS)

Pruess, Karsten; Battistelli, Alfredo

2003-01-01

TMVOC is a numerical simulator for three-phase non-isothermal flow of water, soil gas, and a multicomponent mixture of volatile organic chemicals (VOCs) in multidimensional heterogeneous porous media. It is an extension of the TOUGH2 general-purpose simulation program developed at the Lawrence Berkeley National Laboratory. TMVOC is designed for applications to contamination problems that involve hydrocarbon fuel or organic solvent spills in saturated and unsaturated zones. It can model contaminant behavior under ''natural'' environmental conditions, as well as for engineered systems, such as soil vapor extraction, groundwater pumping, or steam-assisted source remediation. TMVOC is upwards compatible with T2VOC (Falta et al., 1995) and can be initialized from T2VOC-style initial conditions. The main enhancements in TMVOC relative to T2VOC are as follows: a multicomponent mixture of volatile organic chemicals can be modeled; any and all combinations of the three phases water-oil-gas are treated; several non-condensible gases may be present; diffusion is treated in all phases in a manner that is fully coupled with phase partitioning. This paper gives a brief summary of the methodology used in TMVOC as well as highlighting some implementation issues. Simulation of a NAPL spill and subsequent remediation is discussed for a 2-D vertical section of a saturated-unsaturated flow problem

ambient volatile organic compounds pollution and ozone formation

African Journals Online (AJOL)

OLUMAYEDE

2013-08-01

Aug 1, 2013 ... Volatile organic compound (VOC) species react at different rate and exhibit differences in reactivity with respect to ozone formation in polluted urban atmosphere. To assess this, the variations pattern, reactivity relative to OH radical and ozone creation potential of ambient VOCs were investigated in field.

A global perspective on aerosol from low-volatility organic compounds

Directory of Open Access Journals (Sweden)

H. O. T. Pye

2010-05-01

Full Text Available Global production of organic aerosol from primary emissions of semivolatile (SVOCs and intermediate (IVOCs volatility organic compounds is estimated using the global chemical transport model, GEOS-Chem. SVOC oxidation is predicted to be a larger global source of net aerosol production than oxidation of traditional parent hydrocarbons (terpenes, isoprene, and aromatics. Using a prescribed rate constant and reduction in volatility for atmospheric oxidation, the yield of aerosol from SVOCs is predicted to be about 75% on a global, annually-averaged basis. For IVOCs, the use of a naphthalene-like surrogate with different high-NO_x and low-NO_x parameterizations produces a global aerosol yield of about 30%, or roughly 5 Tg/yr of aerosol. Estimates of the total global organic aerosol source presented here range between 60 and 100 Tg/yr. This range reflects uncertainty in the parameters for SVOC volatility, SVOC oxidation, SVOC emissions, and IVOC emissions, as well as wet deposition. The highest estimates result if SVOC emissions are significantly underestimated (by more than a factor of 2 or if wet deposition of the gas-phase semivolatile species is less effective than previous estimates. A significant increase in SVOC emissions, a reduction of the volatility of the SVOC emissions, or an increase in the enthalpy of vaporization of the organic aerosol all lead to an appreciable reduction of prediction/measurement discrepancy. In addition, if current primary organic aerosol (POA inventories capture only about one-half of the SVOC emission and the Henrys Law coefficient for oxidized semivolatiles is on the order of 10³ M/atm, a global estimate of OA production is not inconsistent with the top-down estimate of 140 Tg/yr by (Goldstein and Galbally, 2007. Additional information is needed to constrain the emissions and treatment of SVOCs and IVOCs, which have traditionally not been included in models.

Overview of one transistor type of hybrid organic ferroelectric non-volatile memory

Institute of Scientific and Technical Information of China (English)

Young; Tea; Chun; Daping; Chu

2015-01-01

Organic ferroelectric memory devices based on field effect transistors that can be configured between two stable states of on and off have been widely researched as the next generation data storage media in recent years.This emerging type of memory devices can lead to a new instrument system as a potential alternative to previous non-volatile memory building blocks in future processing units because of their numerous merits such as cost-effective process,simple structure and freedom in substrate choices.This bi-stable non-volatile memory device of information storage has been investigated using several organic or inorganic semiconductors with organic ferroelectric polymer materials.Recent progresses in this ferroelectric memory field,hybrid system have attracted a lot of attention due to their excellent device performance in comparison with that of all organic systems.In this paper,a general review of this type of ferroelectric non-volatile memory is provided,which include the device structure,organic ferroelectric materials,electrical characteristics and working principles.We also present some snapshots of our previous study on hybrid ferroelectric memories including our recent work based on zinc oxide nanowire channels.

Increase in volatilization of organic compounds using air sparging through addition in alcohol in a soil-water system.

Science.gov (United States)

Chao, Huan-Ping; Hsieh, Lin-Han Chiang; Tran, Hai Nguyen

2018-02-15

This study developed a novel method to promote the remediation efficiency of air sparging. According to the enhanced-volatilization theory presented in this study, selected alcohols added to groundwater can highly enhance the volatilization amounts of organic compounds with high Henry's law constants. In this study, the target organic compounds consisted of n-hexane, n-heptane, benzene, toluene, 1,1,2-trichloroethane, and tetrachloroethene. n-pentanol, n-hexanol, and n-heptanol were used to examine the changes in the volatilization amounts of organic compounds in the given period. Two types of soils with high and low organic matter were applied to evaluate the transport of organic compounds in the soil-water system. The volatilization amounts of the organic compounds increased with increasing alcohol concentrations. The volatilization amounts of the test organic compounds exhibited a decreasing order: n-heptanol>n-hexanol>n-pentanol. When 10mg/L n-heptanol was added to the system, the maximum volatilization enhancement rate was 18-fold higher than that in distilled water. Samples of soil with high organic matter might reduce the volatilization amounts by a factor of 5-10. In the present study, the optimal removal efficiency for aromatic compounds was approximately 98%. Copyright © 2017 Elsevier B.V. All rights reserved.

The immobilization of organic liquid wastes

International Nuclear Information System (INIS)

Greenhalgh, W.O.

1986-01-01

This report describes a portland cement immobilization process for the disposal treatment of radioactive organic liquid wastes which would be generated in a FFTF fuels reprocessing line. An incineration system already on-hand was determined to be too costly to operate for the 100 to 400 gallons per year organic liquid. Organic test liquids were dispersed into an aqueous phosphate liquid using an emulsifier. A total of 109 gallons of potential and radioactive aqueous immiscible organic liquid wastes from Hanford 300 Area operations were solidified with portland cement and disposed of as solid waste during a 3 month test program with in-drum mixers. Waste packing efficiencies varied from 32 to 40% and included pump oils, mineral spirits, and TBP-NPH type solvents

Simple plant-based design strategies for volatile organic pollutants

Energy Technology Data Exchange (ETDEWEB)

Narayanan, M.; Erickson, L.E.; Davis, L.C.

1999-12-31

Vegetation which enhances in-situ biodegradation of organic compounds can play a key role in the bioremediation of such contaminants in polluted soils and groundwater. Plants may act directly on some contaminants by degrading them, but their main effect is to enhance microbial populations in the thizosphere. Microbially mediated transformations are thus indirectly facilitated by root exudates which nourish the indigenous microorganisms. Plants may also be viewed as a solar driven pump-and-treat system which can contain a plume and reduce the spread of contaminated water. Laboratory investigations carried out in a growth chamber with alfalfa plants provide evidence for the (microbially mediated) biodegradation of organic compounds such as toluene, phenol and TCE. Alfalfa plants tolerate concentrations of these organics in contaminated water up to 100 mg/L. They facilitate transfer of the contaminants from the saturated to the vadose zone. For volatile organic compounds such as TCE, vegetation provides a controlled release of compounds and hence assures dilution of the TCE evapotranspired into the atmosphere from contaminated soils. Using a range of calculated plausible scenarios, it is shown that intermedia transfer caused by volatilization associated with plants is most unlikely to lead to exceedance of standards for gas phase contamination, for most volatile contaminants. Possible action level exceedances might occur with highly toxic substances including vinyl chloride and carbon tetrachloride, if they re present in ground water at levels above kilogram amounts in a single plume of a few hectares, and released by vigorously growing plants under hot dry conditions. Information needed for the calculation and design of plant-based bioremediation systems for typical sites is discussed in this paper.

HS-SPME analysis of volatile organic compounds of coniferous needle litter

Science.gov (United States)

Isidorov, V. A.; Vinogorova, V. T.; Rafałowski, K.

The composition of volatile emission of Scots pine ( Pinus sylvestris) and spruce ( Picea exelsa) litter was studied by gas chromatography-mass spectrometry (GC-MS) and samples were collected by solid-phase microextraction (SPME) method. The list of identified compounds includes over 60 organic substances of different classes. It was established that volatile emission contain not only components of essential oils of pine and spruce needles but also a large number of organic compounds which are probably secondary metabolites of litter-decomposing fungi. They include lower carbonyl compounds and alcohols as well as products of terpene dehydration and oxidation. These data show that the processes of litter decomposition are an important source of reactive organic compounds under canopy of coniferous forests.

Transport properties of organic liquids

CERN Document Server

Latini, G; Passerini, G

2006-01-01

The liquid state is possibly the most difficult and intriguing state of matter to model. Organic liquids are required, mainly as working fluids, in almost all industrial activities and in most appliances (e.g. in air conditioning). Transport properties (namely dynamic viscosity and thermal conductivity) are possibly the most important properties for the design of devices and appliances. The aim of this book is to present both theoretical approaches and the latest experimental advances on the issue, and to merge them into a wider approach. It concentrates on applicability of models.This book is organized into five chapters plus a data collection. The chapters discuss the following topics: the liquid state and some well-know theories able to explain the behaviour of liquids; a rather complete review of models, based on theoretical assumptions and/or upon physical paradigms, to evaluate heat transfer in organic liquids; a review of several well-known semi-empirical methods to predict the thermal conductivity coe...

Adsorption of volatile organic compounds by polytetra-fluor ethylene

International Nuclear Information System (INIS)

Martinet, J.M.

1958-01-01

The sorption of organic vapours by microporous polytetra-fluor ethylene has been studied gravimetrically using a Mc Bain-Baker type sorption balance. The amount of sorption, the peculiarities observed on the isotherm curves, the small influence of temperature, and smallness of hysteresis suggests that mainly physical adsorption occurs when the temperature is around 25 deg. C. The values of the surface areas obtained from the adsorption isotherms using organic vapours differ greatly from those derived from N 2 adsorption measurements. This discrepancy cannot be completely attributed to differences in the structure and chemical function of the adsorbate molecules, or to the porous structure of the adsorbent. On the contrary, the surface area values obtained by sorbing high volatile freons conform with those measured by nitrogen adsorption, which seems to imply a connection between the area of sorbed monolayers and volatility of the adsorbate. (author) [fr

Flavor Compounds in Pixian Broad-Bean Paste: Non-Volatile Organic Acids and Amino Acids

Directory of Open Access Journals (Sweden)

Hongbin Lin

2018-05-01

Full Text Available Non-volatile organic acids and amino acids are important flavor compounds in Pixian broad-bean paste, which is a traditional Chinese seasoning product. In this study, non-volatile organic acids, formed in the broad-bean paste due to the metabolism of large molecular compounds, are qualitatively and quantitatively determined by high-performance liquid chromatography (HPLC. Amino acids, mainly produced by hydrolysis of soybean proteins, were determined by the amino acid automatic analyzer. Results indicated that seven common organic acids and eighteen common amino acids were found in six Pixian broad-bean paste samples. The content of citric acid was found to be the highest in each sample, between 4.1 mg/g to 6.3 mg/g, and malic acid were between 2.1 mg/g to 3.6 mg/g ranked as the second. Moreover, fumaric acid was first detected in fermented bean pastes albeit with a low content. For amino acids, savory with lower sour taste including glutamine (Gln, glutamic acid (Glu, aspartic acid (Asp and asparagines (Asn were the most abundant, noted to be 6.5 mg/g, 4.0 mg/g, 6.4 mg/g, 4.9 mg/g, 6.2 mg/g and 10.2 mg/g, and bitter taste amino acids followed. More importantly, as important flavor materials in Pixian broad-bean paste, these two groups of substances are expected to be used to evaluate and represent the flavor quality of Pixian broad-bean paste. Moreover, the results revealed that citric acid, glutamic acid, methionine and proline were the most important flavor compounds. These findings are agreat contribution for evaluating the quality and further assessment of Pixian broad-bean paste.

Flavor Compounds in Pixian Broad-Bean Paste: Non-Volatile Organic Acids and Amino Acids.

Science.gov (United States)

Lin, Hongbin; Yu, Xiaoyu; Fang, Jiaxing; Lu, Yunhao; Liu, Ping; Xing, Yage; Wang, Qin; Che, Zhenming; He, Qiang

2018-05-29

Non-volatile organic acids and amino acids are important flavor compounds in Pixian broad-bean paste, which is a traditional Chinese seasoning product. In this study, non-volatile organic acids, formed in the broad-bean paste due to the metabolism of large molecular compounds, are qualitatively and quantitatively determined by high-performance liquid chromatography (HPLC). Amino acids, mainly produced by hydrolysis of soybean proteins, were determined by the amino acid automatic analyzer. Results indicated that seven common organic acids and eighteen common amino acids were found in six Pixian broad-bean paste samples. The content of citric acid was found to be the highest in each sample, between 4.1 mg/g to 6.3 mg/g, and malic acid were between 2.1 mg/g to 3.6 mg/g ranked as the second. Moreover, fumaric acid was first detected in fermented bean pastes albeit with a low content. For amino acids, savory with lower sour taste including glutamine (Gln), glutamic acid (Glu), aspartic acid (Asp) and asparagines (Asn) were the most abundant, noted to be 6.5 mg/g, 4.0 mg/g, 6.4 mg/g, 4.9 mg/g, 6.2 mg/g and 10.2 mg/g, and bitter taste amino acids followed. More importantly, as important flavor materials in Pixian broad-bean paste, these two groups of substances are expected to be used to evaluate and represent the flavor quality of Pixian broad-bean paste. Moreover, the results revealed that citric acid, glutamic acid, methionine and proline were the most important flavor compounds. These findings are agreat contribution for evaluating the quality and further assessment of Pixian broad-bean paste.

Characterisation of the semi-volatile component of Dissolved Organic Matter by Thermal Desorption - Proton Transfer Reaction - Mass Spectrometry

NARCIS (Netherlands)

Materić, Dušan; Peacock, Mike; Kent, Matthew; Cook, Sarah; Gauci, Vincent; Röckmann, Thomas; Holzinger, Rupert

2017-01-01

Proton Transfer Reaction - Mass Spectrometry (PTR-MS) is a sensitive, soft ionisation method suitable for qualitative and quantitative analysis of volatile and semi-volatile organic vapours. PTR-MS is used for various environmental applications including monitoring of volatile organic compounds

Controlling the volatility of the written optical state in electrochromic DNA liquid crystals

Science.gov (United States)

Liu, Kai; Varghese, Justin; Gerasimov, Jennifer Y.; Polyakov, Alexey O.; Shuai, Min; Su, Juanjuan; Chen, Dong; Zajaczkowski, Wojciech; Marcozzi, Alessio; Pisula, Wojciech; Noheda, Beatriz; Palstra, Thomas T. M.; Clark, Noel A.; Herrmann, Andreas

2016-05-01

Liquid crystals are widely used in displays for portable electronic information display. To broaden their scope for other applications like smart windows and tags, new material properties such as polarizer-free operation and tunable memory of a written state become important. Here, we describe an anhydrous nanoDNA-surfactant thermotropic liquid crystal system, which exhibits distinctive electrically controlled optical absorption, and temperature-dependent memory. In the liquid crystal isotropic phase, electric field-induced colouration and bleaching have a switching time of seconds. Upon transition to the smectic liquid crystal phase, optical memory of the written state is observed for many hours without applied voltage. The reorientation of the DNA-surfactant lamellar layers plays an important role in preventing colour decay. Thereby, the volatility of optoelectronic state can be controlled simply by changing the phase of the material. This research may pave the way for developing a new generation of DNA-based, phase-modulated, photoelectronic devices.

Microlayer source of oxygenated volatile organic compounds in the summertime marine Arctic boundary layer

OpenAIRE

Mungall, Emma L.; Abbatt, Jonathan P. D.; Wentzell, Jeremy J. B.; Lee, Alex K. Y.; Thomas, Jennie L.; Blais, Marjolaine; Gosselin, Michel; Miller, Lisa A.; Papakyriakou, Tim; Willis, Megan D.; Liggio, John

2017-01-01

A biogeochemical connection between the atmosphere and the ocean is demonstrated whereby a marine source of oxygenated volatile organic compounds is identified. Compounds of this type are involved in the formation of secondary organic aerosol, which remains one of the most poorly understood components of Earth’s climate system due in part to the diverse sources of its volatile organic compound precursors. This is especially the case for marine environments, where there are more oxygenated vol...

Characterization of microbial and chemical composition of shuttle wet waste with permanent gas and volatile organic compound analyses

Science.gov (United States)

Peterson, B. V.; Hummerick, M.; Roberts, M. S.; Krumins, V.; Kish, A. L.; Garland, J. L.; Maxwell, S.; Mills, A.

2004-01-01

Solid-waste treatment in space for Advanced Life Support, ALS, applications requires that the material can be safely processed and stored in a confined environment. Many solid-wastes are not stable because they are wet (40-90% moisture) and contain levels of soluble organic compounds that can contribute to the growth of undesirable microorganisms with concomitant production of noxious odors. In the absence of integrated Advanced Life Support systems on orbit, permanent gas, trace volatile organic and microbiological analyses were performed on crew refuse returned from the volume F "wet" trash of three consecutive Shuttle missions (STS-105, 109, and 110). These analyses were designed to characterize the short-term biological stability of the material and assess potential crew risks resulting from microbial decay processes during storage. Waste samples were collected post-orbiter landing and sorted into packaging material, food waste, toilet waste, and bulk liquid fractions deposited during flight in the volume F container. Aerobic and anaerobic microbial loads were determined in each fraction by cultivation on R2A and by acridine orange direct count (AODC). Dry and ash weights were performed to determine both water and organic content of the materials. Experiments to determine the aerobic and anaerobic biostability of refuse stored for varying periods of time were performed by on-line monitoring of CO2 and laboratory analysis for production of hydrogen sulfide and methane. Volatile organic compounds and permanent gases were analyzed using EPA Method TO15 by USEPA et al. [EPA Method TO15, The Determination of Volatile Organic Compounds (VOCs) in Ambient Air using SUMMA, Passivated Canister Sampling and Gas Chromatographic Analysis,1999] with gas chromatography/mass spectrometry and by gas chromatography with selective detectors. These baseline measures of waste stream content, labile organics, and microbial load in the volume F Shuttle trash provide data for waste

Diffusivity measurements of volatile organics in levitated viscous aerosol particles

Science.gov (United States)

Bastelberger, Sandra; Krieger, Ulrich K.; Luo, Beiping; Peter, Thomas

2017-07-01

Field measurements indicating that atmospheric secondary organic aerosol (SOA) particles can be present in a highly viscous, glassy state have spurred numerous studies addressing low diffusivities of water in glassy aerosols. The focus of these studies is on kinetic limitations of hygroscopic growth and the plasticizing effect of water. In contrast, much less is known about diffusion limitations of organic molecules and oxidants in viscous matrices. These may affect atmospheric chemistry and gas-particle partitioning of complex mixtures with constituents of different volatility. In this study, we quantify the diffusivity of a volatile organic in a viscous matrix. Evaporation of single particles generated from an aqueous solution of sucrose and small amounts of volatile tetraethylene glycol (PEG-4) is investigated in an electrodynamic balance at controlled relative humidity (RH) and temperature. The evaporative loss of PEG-4 as determined by Mie resonance spectroscopy is used in conjunction with a radially resolved diffusion model to retrieve translational diffusion coefficients of PEG-4. Comparison of the experimentally derived diffusivities with viscosity estimates for the ternary system reveals a breakdown of the Stokes-Einstein relationship, which has often been invoked to infer diffusivity from viscosity. The evaporation of PEG-4 shows pronounced RH and temperature dependencies and is severely depressed for RH ≲ 30 %, corresponding to diffusivities pollutant molecules such as polycyclic aromatic hydrocarbons (PAHs).

Reforming sewage sludge pyrolysis volatile with Fe-embedded char: Minimization of liquid product yield.

Science.gov (United States)

Yu, Guotao; Chen, Dezhen; Arena, Umberto; Huang, Zhen; Dai, Xiaohu

2018-03-01

Obtaining high quality syngas from sewage sludge (SS) means transferring a low-grade SS into a high-grade fuel or raw materials for chemical products. In this study, Fe is added to SS in form of Fe 2 (SO 4 ) 3 to produce an effective and self-sufficient catalyst in order to obtain more syngas and minimize liquid products from SS pyrolysis. The Fe-embedded sewage sludge chars (SSCs) were used as catalysts for volatile reforming at 600°C. It has been found that the gas yield increases from 15.9 to 35.8wt% of the SS and that of liquids decreases from 31.9 to 10.2wt% after volatile reforming with Fe-embedded SSC when Fe was added equal to 7 % in the dried SS. In addition, the content of nitrogen-containing compounds in the oily products decreased. After reforming with Fe-embedded SSC, the molar fractions of syngas combustible components, including H 2 , CH 4 and CO, increase, and the higher heating value of the syngas increased to 17.0MJ/Nm 3 from the original 12.5MJ/Nm 3 obtained from SS pyrolysis at 550°C. Moreover, the volatile reforming seems to reduce the level of some important syngas pollutants, like H 2 S, HCl and HCN, even though it was also observed an increase of the contents of SO 2 , NH 3 , NO 2, HCNO and N 2 O. Copyright © 2017 Elsevier Ltd. All rights reserved.

Molecular corridors and parameterizations of volatility in the chemical evolution of organic aerosols

Directory of Open Access Journals (Sweden)

Y. Li

2016-03-01

Full Text Available The formation and aging of organic aerosols (OA proceed through multiple steps of chemical reaction and mass transport in the gas and particle phases, which is challenging for the interpretation of field measurements and laboratory experiments as well as accurate representation of OA evolution in atmospheric aerosol models. Based on data from over 30 000 compounds, we show that organic compounds with a wide variety of functional groups fall into molecular corridors, characterized by a tight inverse correlation between molar mass and volatility. We developed parameterizations to predict the saturation mass concentration of organic compounds containing oxygen, nitrogen, and sulfur from the elemental composition that can be measured by soft-ionization high-resolution mass spectrometry. Field measurement data from new particle formation events, biomass burning, cloud/fog processing, and indoor environments were mapped into molecular corridors to characterize the chemical nature of the observed OA components. We found that less-oxidized indoor OA are constrained to a corridor of low molar mass and high volatility, whereas highly oxygenated compounds in atmospheric water extend to high molar mass and low volatility. Among the nitrogen- and sulfur-containing compounds identified in atmospheric aerosols, amines tend to exhibit low molar mass and high volatility, whereas organonitrates and organosulfates follow high O : C corridors extending to high molar mass and low volatility. We suggest that the consideration of molar mass and molecular corridors can help to constrain volatility and particle-phase state in the modeling of OA particularly for nitrogen- and sulfur-containing compounds.

Volatile and semivolatile organic compounds in laboratory peat fire emissions

Data.gov (United States)

U.S. Environmental Protection Agency — Supporting information Tables S3 and S4 list emission factors in g/kg of speciated volatile and particulate organic compounds emitted from peat burning. Peat samples...

Datasets used in the manuscript titled "Nitrate radicals and biogenic volatile organic compounds: oxidation, mechanisms and organic aerosol"

Data.gov (United States)

U.S. Environmental Protection Agency — This dataset documents that all of the data used in the manuscript "Nitrate radicals and biogenic volatile organic compounds: oxidation, mechanisms, and organic...

Nanostructured Polypyrrole-Based Ammonia and Volatile Organic Compound Sensors

Directory of Open Access Journals (Sweden)

Milena Šetka

2017-03-01

Full Text Available The aim of this review is to summarize the recent progress in the fabrication of efficient nanostructured polymer-based sensors with special focus on polypyrrole. The correlation between physico-chemical parameters, mainly morphology of various polypyrrole nanostructures, and their sensitivity towards selected gas and volatile organic compounds (VOC is provided. The different approaches of polypyrrole modification with other functional materials are also discussed. With respect to possible sensors application in medicine, namely in the diagnosis of diseases via the detection of volatile biomarkers from human breath, the sensor interaction with humidity is described as well. The major attention is paid to analytes such as ammonia and various alcohols.

Liquid crystals for organic transistors (Conference Presentation)

Science.gov (United States)

Hanna, Jun-ichi; Iino, Hiroaki

2016-09-01

Liquid crystals are a new type of organic semiconductors exhibiting molecular orientation in self-organizing manner, and have high potential for device applications. In fact, various device applications have been proposed so far, including photosensors, solar cells, light emitting diodes, field effect transistors, and so on.. However, device performance in those fabricated with liquid crystals is less than those of devices fabricated with conventional materials in spite of unique features of liquid crystals. Here we discuss how we can utilize the liquid crystallinity in organic transistors and how we can overcome conventional non-liquid crystalline organic transistor materials. Then, we demonstrate high performance organic transistors fabricated with a smectic E liquid crystal of Ph-BTBT-10, which show high mobility of over 10cm2/Vs and high thermal durability of over 200oC in OFETs fabricated with its spin-coated polycrystalline thin films.

Atomic and molecular physics of plasma-based environmental technologies for abatement of volatile organic compounds

International Nuclear Information System (INIS)

Penetrante, B. M.; Hsiao, M. C.; Bardsley, J. N.; Merritt, B. T.; Vogtin, G. E.; Kuthi, A.; Burkhart, C. P.; Bayless, J. R.

1997-01-01

Non-thermal plasma techniques represent a new generation of air emission control technology that potentially could treat large-volume emissions containing dilute concentrations of volatile organic compounds. In order to apply non-thermal plasmas in an industrial scale, it is important to establish the electrical power requirements and byproducts of the process.There is a need for reliable data concerning the primary decomposition mechanisms and subsequent chemical kinetics associated with non- thermal plasma processing of volatile organic compounds. There are many basic atomic and molecular physics issues that are essential in evaluating the economic performance of non-thermal plasma reactors. These studies are important in understanding how the input electrical power is dissipated in the plasma and how efficiently it is converted to the production of the plasma species (radicals, ions or electrons) responsible for the decomposition of the volatile organic compounds. This paper will present results from basic experimental and theoretical studies aimed at identifying the reaction mechanisms responsible for the primary decomposition of various types of volatile organic compounds. (authors)

40 CFR 60.542 - Standards for volatile organic compounds.

Science.gov (United States)

2010-07-01

... PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for the Rubber Tire Manufacturing Industry § 60.542 Standards for volatile organic compounds. (a) On and after the date on which the initial performance test, required by § 60.8, is completed, but no later than...

Development of the colorimetric sensor array for detection of explosives and volatile organic compounds in air

DEFF Research Database (Denmark)

Kostesha, Natalie; Alstrøm, Tommy Sonne; Johnsen, C

2010-01-01

a color difference map which gives a unique fingerprint for each explosive and volatile organic compound. Such sensing technology can be used to screen for relevant explosives in a complex background as well as to distinguish mixtures of volatile organic compounds distributed in gas phase. This sensor......In the framework of the research project 'Xsense' at the Technical University of Denmark (DTU) we are developing a simple colorimetric sensor array which can be useful in detection of explosives like DNT and TNT, and identification of volatile organic compounds in the presence of water vapor in air...

The impact of the introduction of index options on volatility and liquidity on the underlying stocks : Empirical evidence from the Asian stock markets

OpenAIRE

Hasan, Md Kamrul; Chowdhury, Shabyashachi

2011-01-01

The impact of the introduction of derivatives on the underlying stock is a debatable topic among the researchers. The issue is quite controversial as contradictory results have been obtained by researchers in various stock markets. The purpose of this study is to examine the volatility and the liquidity effect on the underlying stock after the introduction of index options. We have investigated volatility and liquidity effect by collecting sample data from the stock markets of India, Korea, T...

Modeling long-term uptake and re-volatilization of semi-volatile organic compounds (SVOCs) across the soil-atmosphere interface.

Science.gov (United States)

Bao, Zhongwen; Haberer, Christina; Maier, Uli; Beckingham, Barbara; Amos, Richard T; Grathwohl, Peter

2015-12-15

Soil-atmosphere exchange is important for the environmental fate and atmospheric transport of many semi-volatile organic compounds (SVOCs). This study focuses on modeling the vapor phase exchange of semi-volatile hydrophobic organic pollutants between soil and the atmosphere using the multicomponent reactive transport code MIN3P. MIN3P is typically applied to simulate aqueous and vapor phase transport and reaction processes in the subsurface. We extended the code to also include an atmospheric boundary layer where eddy diffusion takes place. The relevant processes and parameters affecting soil-atmosphere exchange were investigated in several 1-D model scenarios and at various time scales (from years to centuries). Phenanthrene was chosen as a model compound, but results apply for other hydrophobic organic compounds as well. Gaseous phenanthrene was assumed to be constantly supplied to the system during a pollution period and a subsequent regulation period (with a 50% decline in the emission rate). Our results indicate that long-term soil-atmosphere exchange of phenanthrene is controlled by the soil compartment - re-volatilization thus depends on soil properties. A sensitivity analysis showed that accumulation and transport in soils in the short term is dominated by diffusion, whereas in the long term groundwater recharge and biodegradation become relevant. As expected, sorption causes retardation and slows down transport and biodegradation. If atmospheric concentration is reduced (e.g. after environmental regulations), re-volatilization from soil to the atmosphere occurs only for a relatively short time period. Therefore, the model results demonstrate that soils generally are sinks for atmospheric pollutants. The atmospheric boundary layer is only relevant for time scales of less than one month. The extended MIN3P code can also be applied to simulate fluctuating concentrations in the atmosphere, for instance due to temperature changes in the topsoil. Copyright �

Modeling organic aerosols in a megacity: potential contribution of semi-volatile and intermediate volatility primary organic compounds to secondary organic aerosol formation

Directory of Open Access Journals (Sweden)

A. Hodzic

2010-06-01

Full Text Available It has been established that observed local and regional levels of secondary organic aerosols (SOA in polluted areas cannot be explained by the oxidation and partitioning of anthropogenic and biogenic VOC precursors, at least using current mechanisms and parameterizations. In this study, the 3-D regional air quality model CHIMERE is applied to estimate the potential contribution to SOA formation of recently identified semi-volatile and intermediate volatility organic precursors (S/IVOC in and around Mexico City for the MILAGRO field experiment during March 2006. The model has been updated to include explicitly the volatility distribution of primary organic aerosols (POA, their gas-particle partitioning and the gas-phase oxidation of the vapors. Two recently proposed parameterizations, those of Robinson et al. (2007 ("ROB" and Grieshop et al. (2009 ("GRI" are compared and evaluated against surface and aircraft measurements. The 3-D model results are assessed by comparing with the concentrations of OA components from Positive Matrix Factorization of Aerosol Mass Spectrometer (AMS data, and for the first time also with oxygen-to-carbon ratios derived from high-resolution AMS measurements. The results show a substantial enhancement in predicted SOA concentrations (2–4 times with respect to the previously published base case without S/IVOCs (Hodzic et al., 2009, both within and downwind of the city leading to much reduced discrepancies with the total OA measurements. Model improvements in OA predictions are associated with the better-captured SOA magnitude and diurnal variability. The predicted production from anthropogenic and biomass burning S/IVOC represents 40–60% of the total measured SOA at the surface during the day and is somewhat larger than that from commonly measured aromatic VOCs, especially at the T1 site at the edge of the city. The SOA production from the continued multi-generation S/IVOC oxidation products continues actively

Visualization of residual organic liquid trapped in aquifers

International Nuclear Information System (INIS)

Conrad, S.H.; Wilson, J.L.; Mason, W.R.; Peplinski, W.J.

1992-01-01

Organic liquids that are essentially immiscible with water migrate through the subsurface under the influence of capillary, viscous, and buoyancy forces. These liquids originate from the improper disposal of hazardous wastes, and the spills and leaks of petroleum hydrocarbons and solvents. The flow visualization experiments described in this study examined the migration of organic liquids through the saturated zone of aquifers, with a primary focus on the behavior of the residual organic liquid saturation, referring to that portion of the organic liquid that is trapped by capillary forces. Etched glass micromodels were used to visually observe dynamic multiphase displacement processes in pore networks. The resulting fluid distributions were photographed. Pore and blob casts were produced by a technique in which an organic liquid was solidified in place within a sand column at the conclusion of a displacement. The columns were sectioned and examined under optical and scanning electron microscopes. Photomicrographs of these sections show the morphology of the organic phase and its location within the sand matrix. The photographs from both experimental techniques reveal that in the saturated zone large amounts of residual organic liquid are trapped as isolated blobs of microscopic size. The size, shape, and spatial distribution of these blobs of residual organic liquid affect the dissolution of organic liquid into the water phase and the biotransformation of organic components. These processes are of concern for the prediction of pollution migration and the design of aquifer remediation schemes

Development of a novel biofilter for aerobic biodegradation of volatile organic compounds (VOCs)

International Nuclear Information System (INIS)

Govind, R.; Utgikar, V.; Shan, Y.; Zhao, Wang; Sayles, G.D.; Bishop, D.F.; Safferman, S.I.

1992-01-01

In recent years, the emission into the atmosphere of volatile organic compounds (VOCs) has undergone increased regulation by EPA, OSHA and other government agencies due to potential human health hazards. The sources of these VOCs include releases during industrial production and use, from contaminated wastewaters in collection systems and treatment plants, and from hazardous wastes in landfills and contaminated ground water. Conventional methods for treating VOC emissions include adsorption on solids, absorption in solvents, incineration and catalytic oxidation. One alternative to these conventional treatment methods is the biological destruction of the VOCs in gas phase biofilters. This method has the advantage of pollution destruction (as compared to transfer to another medium) at lower operation and maintenance costs. The biofilter method also can be combined with various stripping or vapor extraction separation processes which effectively transfer VOCs from liquid or solid matrices into the gas phase entering biofilters

Adsorption of Volatile Organic Compounds from Aqueous Solution by Granular Activated Carbon in Batch System

International Nuclear Information System (INIS)

Zeinali, F.; Ghoreyshi, A. A.; Najafpour, G.

2011-01-01

Chlorinated hydrocarbons and aromatics are the major volatile organic compounds that contaminate the ground water and industrial waste waters. The best way to overcome this problem is to recover the dissolved compounds in water. In order to evaluate the potential ability of granular activated carbon for recovery of volatile organic compounds from water, the equilibrium adsorption was investigated. This study deals with the adsorption of dichloromethane as a typical chlorinated volatile organic compound and toluene as the representative of aromatic volatile organic compounds on a commercial granular activated carbon. The adsorption isotherms of these two volatile organic compounds on granular activated carbon were measured at three different temperatures, toluene at 293, 303 and 313 K and dichloromethane at 298, 303 and 313 K within their solubility concentration range in water. The maximum adsorption capacity of dichloromethane and toluene adsorption by granular activated carbon was 4 and 0.2 mol/Kg-1, respectively. The experimental data obtained were correlated with different adsorption isotherm models. The Langmuir model was well adapted to the description of dichloromethane adsorption on granular activated carbon at all three temperatures, while the adsorption of toluene on granular activated carbon was found to be well described by the Langmuir-BET hybrid model at all three temperatures. The heat of adsorption was also calculated based on the thermodynamic equation of Clausius Clapeyron, which indicates the adsorption process is endothermic for both compounds.

Volatile Organic Compounds (VOCs) in the Ambient Air Of Concentration Unit of Sar-Cheshmeh Copper Complex

International Nuclear Information System (INIS)

Faghihi-Zrandi, A.; Akhgar, M. R.

2016-01-01

Air pollutants including gases, vapors and particles, are emitted from different sources. Volatile organic compounds are the most important pollutants in the ambient air of industries. The present study was carried out to identify and measurement of volatile organic compounds in concentration unit of Sar-Cheshmeh Copper Complex. In this study, sampling of the volatile organic compounds was done by using activated charcoal tube. To identify and measure these compounds gas chromatography/mass spectroscopy were used. Thirteen volatile organic compounds were identified in the ambient air of concentration unit. Among these compounds, the mean value and maximum concentration of isopropyl alcohol and nonane were 255, 640 μg/m3 and 1577, 14400 μg/m3, respectively. By using SPSS software and independent sample t- test, showed that there were no significant difference between mean value concentration of isopropyl alcohol and nonane in the ambient air and TLV values of these compounds (isopropyl alcohol; 200 ppm and nonane; 200 ppm) (P >0.05).

Organic non-volatile memories from ferroelectric phase-separated blends

Science.gov (United States)

Asadi, Kamal; de Leeuw, Dago M.; de Boer, Bert; Blom, Paul W. M.

2008-07-01

New non-volatile memories are being investigated to keep up with the organic-electronics road map. Ferroelectric polarization is an attractive physical property as the mechanism for non-volatile switching, because the two polarizations can be used as two binary levels. However, in ferroelectric capacitors the read-out of the polarization charge is destructive. The functionality of the targeted memory should be based on resistive switching. In inorganic ferroelectrics conductivity and ferroelectricity cannot be tuned independently. The challenge is to develop a storage medium in which the favourable properties of ferroelectrics such as bistability and non-volatility can be combined with the beneficial properties provided by semiconductors such as conductivity and rectification. Here we present an integrated solution by blending semiconducting and ferroelectric polymers into phase-separated networks. The polarization field of the ferroelectric modulates the injection barrier at the semiconductor-metal contact. The combination of ferroelectric bistability with (semi)conductivity and rectification allows for solution-processed non-volatile memory arrays with a simple cross-bar architecture that can be read out non-destructively. The concept of an electrically tunable injection barrier as presented here is general and can be applied to other electronic devices such as light-emitting diodes with an integrated on/off switch.

Crude glycerol combustion: Particulate, acrolein, and other volatile organic emissions

KAUST Repository

Steinmetz, Scott; Herrington, Jason S.; Winterrowd, Chris K.; Roberts, William L.; Wendt, Jost O L; Linak, William P.

2013-01-01

to be formed from the low temperature thermal decomposition of glycerol. Currently, there is no known reliable method for measuring acrolein in sources. Acrolein and emissions of other volatile organic compounds were characterized through the use of a SUMMA

Streptopyridines, volatile pyridine alkaloids produced by Streptomyces sp. FORM5

Directory of Open Access Journals (Sweden)

Ulrike Groenhagen

2014-06-01

Full Text Available Streptomyces sp. FORM5 is a bacterium that is known to produce the antibiotic streptazolin and related compounds. We investigated the strain for the production of volatiles using the CLSA (closed-loop stripping analysis method. Liquid and agar plate cultures revealed the formation of new 2-alkylpyridines (streptopyridines, structurally closely related to the already known 2-pentadienylpiperidines. The structures of the streptopyridines A to E were confirmed by total synthesis. The analysis of the liquid phase by solvent extraction or extraction with an Oasis adsorbent showed that streptazolin and 2-pentadienylpiperidine are the major compounds, while the streptopyridines are only minor components. In the gas phase, only the streptopyridines could be detected. Therefore, an orthogonal set of analysis is needed to assess the metabolic profile of bacteria, because volatile compounds are obviously overlooked by traditional analytical methods. The streptopyridines are strain specific volatiles that are accompanied by a broad range of headspace constituents that occur in many actinomycetes. Volatiles might be of ecological importance for the producing organism, and, as biosynthetic intermediates or shunt products, they can be useful as indicators of antibiotic production in a bacterium.

Analysis of volatile organic compounds of ‘Fuji’ apples following electron beam irradiation and storage

International Nuclear Information System (INIS)

Song, Hyun-Pa; Shim, Sung-Lye; Lee, Sun-Im; Kim, Dong-Ho; Kwon, Joong-Ho; Kim, Kyong-Su

2012-01-01

The volatile organic compounds of non-irradiated and electron-beam irradiated ‘Fuji’ apples (Malus domestica Borkh.) at 0, 0.5, and 1 kGy were isolated through simultaneous distillation extractions and analyzed using gas chromatograph–mass spectrometry. A total of 53 volatile organic compounds were characterized in 0 and 1 kGy irradiated samples, whereas two more compounds related to ketone and terpenoid group were identified in 0.5 kGy irradiated samples. The contents of volatile compounds were 24.33, 36.49, and 35.28 mg/kg in 0, 0.5, and 1 kGy irradiated samples, respectively. The major compounds identified were butanol, hexanal, [E]-2-hexenal, and hexanol in all samples. The relative content of alcohol increased after 30 days of storage in all samples, whereas that of aldehyde decreased. Although the contents of some volatile compounds were changed by electron-beam irradiation, the total yield and major flavor compounds of irradiated ‘Fuji’ apples were similar to, or even greater than, those of the control. Therefore, the application of e-beam irradiation if required for microbial decontamination of ‘Fuji’ apples is an acceptable method as it does not bring about any major quantitative changes of volatile organic compounds. - Highlights: ► We analyzed the volatile organic compounds of electron beam irradiated Fuji apples. ► The major compounds of samples were butanol, hexanal, [E]-2-hexenal, and hexanol. ► The contents of major flavor compounds of non-irradiated and irradiated samples were similar.

Sensory irritating potency of some microbial volatile organic compounds (MVOCs) and a mixture of five MVOCs.

Science.gov (United States)

Korpi, A; Kasanen, J P; Alarie, Y; Kosma, V M; Pasanen, A L

1999-01-01

The authors investigated the ability/potencies of 3 microbial volatile organic compounds and a mixture of 5 microbial volatile organic compounds to cause eye and upper respiratory tract irritation (i.e., sensory irritation), with an animal bioassay. The authors estimated potencies by determining the concentration capable of decreasing the respiratory frequency of mice by 50% (i.e., the RD50 value). The RD50 values for 1-octen-3-ol, 3-octanol, and 3-octanone were 182 mg/m3 (35 ppm), 1359 mg/m3 (256 ppm), and 17586 mg/m3 (3360 ppm), respectively. Recommended indoor air levels calculated from the individual RD50 values for 1-octen-3-ol, 3-octanol, and 3-octanone were 100, 1000, and 13000 microg/m3, respectively-values considerably higher than the reported measured indoor air levels for these compounds. The RD50 value for a mixture of 5 microbial volatile organic compounds was also determined and found to be 3.6 times lower than estimated from the fractional concentrations and the respective RD50s of the individual components. The data support the conclusion that a variety of microbial volatile organic compounds may have some synergistic effects for the sensory irritation response, which constrains the interpretation and application of recommended indoor air levels of individual microbial volatile organic compounds. The results also showed that if a particular component of a mixture was much more potent than the other components, it may dominate the sensory irritation effect. With respect to irritation symptoms reported in moldy houses, the results of this study indicate that the contribution of microbial volatile organic compounds to these symptoms seems less than previously supposed.

Determination of Volatile Organic Compounds in Selected Strains of Cyanobacteria

Directory of Open Access Journals (Sweden)

Ivan Milovanović

2015-01-01

Full Text Available Microalgal biomass can be used in creating various functional food and feed products, but certain species of microalgae and cyanobacteria are known to produce various compounds causing off-flavour. In this work, we investigated selected cyanobacterial strains of Spirulina, Anabaena, and Nostoc genera originating from Serbia, with the aim of determining the chemical profile of volatile organic compounds produced by these organisms. Additionally, the influence of nitrogen level during growth on the production of volatile compounds was investigated for Nostoc and Anabaena strains. In addition, multivariate techniques, namely, principal component analysis (PCA and hierarchical cluster analysis (HCA, were used for making distinction among different microalgal strains. The results show that the main volatile compounds in these species are medium chain length alkanes, but other odorous compounds such as 2-methylisoborneol (0.51–4.48%, 2-pentylfuran (0.72–8.98%, β-cyclocitral (0.00–1.17%, and β-ionone (1.15–2.72% were also detected in the samples. Addition of nitrogen to growth medium was shown to negatively affect the production of 2-methylisoborneol, while geosmin was not detected in any of the analyzed samples, which indicates that the manipulation of growth conditions may be useful in reducing levels of some unwanted odor-causing components.

A Computer Model for Analyzing Volatile Removal Assembly

Science.gov (United States)

Guo, Boyun

2010-01-01

A computer model simulates reactional gas/liquid two-phase flow processes in porous media. A typical process is the oxygen/wastewater flow in the Volatile Removal Assembly (VRA) in the Closed Environment Life Support System (CELSS) installed in the International Space Station (ISS). The volatile organics in the wastewater are combusted by oxygen gas to form clean water and carbon dioxide, which is solved in the water phase. The model predicts the oxygen gas concentration profile in the reactor, which is an indicator of reactor performance. In this innovation, a mathematical model is included in the computer model for calculating the mass transfer from the gas phase to the liquid phase. The amount of mass transfer depends on several factors, including gas-phase concentration, distribution, and reaction rate. For a given reactor dimension, these factors depend on pressure and temperature in the reactor and composition and flow rate of the influent.

User's guide for polyethylene-based passive diffusion bag samplers to obtain volatile organic compound concentrations in wells. Part 2, Field tests

Science.gov (United States)

Vroblesky, Don A.

2001-01-01

Diffusion samplers installed in observation wells were found to be capable of yielding representative water samples for chlorinated volatile organic compounds. The samplers consisted of polyethylene bags containing deionized water and relied on diffusion of chlorinated volatile organic compounds through the polyethylene membrane. The known ability of polyethylene to transmit other volatile compounds, such as benzene and toluene, indicates that the samplers can be used for a variety of volatile organic compounds. In wells at the study area, the volatile organic compound concentrations in water samples obtained using the samplers without prior purging were similar to concentrations in water samples obtained from the respective wells using traditional purging and sampling approaches. The low cost associated with this approach makes it a viable option for monitoring large observation-well networks for volatile organic compounds.

The development of a volatile organics concentrator for use in monitoring Space Station water quality

Science.gov (United States)

Bodek, Itamar; Ehntholt, Daniel J.; Stolki, Thomas J.; Valentine, James R.; Trabanino, Rudy; Webb, Johanna V.; Sauer, Richard L.

1991-01-01

A breadboard concept of a volatile organics concentrator (VOC) is manufactured and tested for optimized water-quality analysis in a space environment. The VOC system is attached to a gas chromatograph/mass spectrometer to analyze the volatile chemicals relevant to the operation of Space Station Freedom. The preliminary tests include: (1) comparisons with analyses based on direct on-column injections of standards; (2) analyses of iodinated volatile organics; (3) comparisons of nitrogen vs helium as the chromatography carrier gas; and (4) measurements of collection efficiency. The VOC can analyze EPA method-624 analytes at comparable detection using flame-ionization detection and can analyze volatile iodinated compounds. The breadboard has good reproducibility and can use nitrogen as a carrier gas; good results are noted for the collection and concentration levels and for water removal.

Metal-organic molecular device for non-volatile memory storage

International Nuclear Information System (INIS)

Radha, B.; Sagade, Abhay A.; Kulkarni, G. U.

2014-01-01

Non-volatile memory devices have been of immense research interest for their use in active memory storage in powered off-state of electronic chips. In literature, various molecules and metal compounds have been investigated in this regard. Molecular memory devices are particularly attractive as they offer the ease of storing multiple memory states in a unique way and also represent ubiquitous choice for miniaturized devices. However, molecules are fragile and thus the device breakdown at nominal voltages during repeated cycles hinders their practical applicability. Here, in this report, a synergetic combination of an organic molecule and an inorganic metal, i.e., a metal-organic complex, namely, palladium hexadecylthiolate is investigated for memory device characteristics. Palladium hexadecylthiolate following partial thermolysis is converted to a molecular nanocomposite of Pd(II), Pd(0), and long chain hydrocarbons, which is shown to exhibit non-volatile memory characteristics with exceptional stability and retention. The devices are all solution-processed and the memory action stems from filament formation across the pre-formed cracks in the nanocomposite film.

Volatile organic pollutants in iron and steel industry

International Nuclear Information System (INIS)

Manea, D.; Dorina, S.; Popescu, L.; Stoian, P.

2009-01-01

It is a well known fact that iron and steel units generate about 25% from total gaseous emissions, and a significant part of these are diffuse emissions, which appear during technological stages. so that, apart from other types of pollutants, appear volatile organic compounds (VOCs) that contain a considerable number of diverse and complex substances that, even in small amounts, affect all environmental factors: air, water, soil. (Author)

Estimation of the volatility distribution of organic aerosol combining thermodenuder and isothermal dilution measurements

Directory of Open Access Journals (Sweden)

E. E. Louvaris

2017-10-01

Full Text Available A method is developed following the work of Grieshop et al. (2009 for the determination of the organic aerosol (OA volatility distribution combining thermodenuder (TD and isothermal dilution measurements. The approach was tested in experiments that were conducted in a smog chamber using organic aerosol (OA produced during meat charbroiling. A TD was operated at temperatures ranging from 25 to 250 °C with a 14 s centerline residence time coupled to a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS and a scanning mobility particle sizer (SMPS. In parallel, a dilution chamber filled with clean air was used to dilute isothermally the aerosol of the larger chamber by approximately a factor of 10. The OA mass fraction remaining was measured as a function of temperature in the TD and as a function of time in the isothermal dilution chamber. These two sets of measurements were used together to estimate the volatility distribution of the OA and its effective vaporization enthalpy and accommodation coefficient. In the isothermal dilution experiments approximately 20 % of the OA evaporated within 15 min. Almost all the OA evaporated in the TD at approximately 200 °C. The resulting volatility distributions suggested that around 60–75 % of the cooking OA (COA at concentrations around 500 µg m−3 consisted of low-volatility organic compounds (LVOCs, 20–30 % of semivolatile organic compounds (SVOCs, and around 10 % of intermediate-volatility organic compounds (IVOCs. The estimated effective vaporization enthalpy of COA was 100 ± 20 kJ mol−1 and the effective accommodation coefficient was 0.06–0.07. Addition of the dilution measurements to the TD data results in a lower uncertainty of the estimated vaporization enthalpy as well as the SVOC content of the OA.

Estimation of the volatility distribution of organic aerosol combining thermodenuder and isothermal dilution measurements

Science.gov (United States)

Louvaris, Evangelos E.; Karnezi, Eleni; Kostenidou, Evangelia; Kaltsonoudis, Christos; Pandis, Spyros N.

2017-10-01

A method is developed following the work of Grieshop et al. (2009) for the determination of the organic aerosol (OA) volatility distribution combining thermodenuder (TD) and isothermal dilution measurements. The approach was tested in experiments that were conducted in a smog chamber using organic aerosol (OA) produced during meat charbroiling. A TD was operated at temperatures ranging from 25 to 250 °C with a 14 s centerline residence time coupled to a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) and a scanning mobility particle sizer (SMPS). In parallel, a dilution chamber filled with clean air was used to dilute isothermally the aerosol of the larger chamber by approximately a factor of 10. The OA mass fraction remaining was measured as a function of temperature in the TD and as a function of time in the isothermal dilution chamber. These two sets of measurements were used together to estimate the volatility distribution of the OA and its effective vaporization enthalpy and accommodation coefficient. In the isothermal dilution experiments approximately 20 % of the OA evaporated within 15 min. Almost all the OA evaporated in the TD at approximately 200 °C. The resulting volatility distributions suggested that around 60-75 % of the cooking OA (COA) at concentrations around 500 µg m-3 consisted of low-volatility organic compounds (LVOCs), 20-30 % of semivolatile organic compounds (SVOCs), and around 10 % of intermediate-volatility organic compounds (IVOCs). The estimated effective vaporization enthalpy of COA was 100 ± 20 kJ mol-1 and the effective accommodation coefficient was 0.06-0.07. Addition of the dilution measurements to the TD data results in a lower uncertainty of the estimated vaporization enthalpy as well as the SVOC content of the OA.

Volatile organic compounds in the unsaturated zone from radioactive wastes

Science.gov (United States)

Baker, Ronald J.; Andraski, Brian J.; Stonestrom, David A.; Luo, Wentai

2012-01-01

Volatile organic compounds (VOCs) are often comingled with low-level radioactive wastes (LLRW), but little is known about subsurface VOC emanations from LLRW landfills. The current study systematically quantified VOCs associated with LLRW over an 11-yr period at the USGS Amargosa Desert Research Site (ADRS) in southwestern Nevada. Unsaturated-zone gas samples of VOCs were collected by adsorption on resin cartridges and analyzed by thermal desorption and GC/MS. Sixty of 87 VOC method analytes were detected in the 110-m-thick unsaturated zone surrounding a LLRW disposal facility. Chlorofluorocarbons (CFCs) were detected in 100% of samples collected. Chlorofluorocarbons are powerful greenhouse gases, deplete stratospheric ozone, and are likely released from LLRW facilities worldwide. Soil-gas samples collected from a depth of 24 m and a horizontal distance 100 m south of the nearest waste-disposal trench contained >60,000 ppbv total VOCs, including >37,000 ppbv CFCs. Extensive sampling in the shallow unsaturated zone (0–2 m deep) identified areas where total VOC concentrations exceeded 5000 ppbv at the 1.5-m depth. Volatile organic compound concentrations exceeded background levels up to 300 m from the facility. Maximum vertical diffusive fluxes of total VOCs were estimated to be 1 g m-2 yr-1. Volatile organic compound distributions were similar but not identical to those previously determined for tritium and elemental mercury. To our knowledge, this study is the first to characterize the unsaturated zone distribution of VOCs emanating from a LLRW landfill. Our results may help explain anomalous transport of radionuclides at the ADRS and elsewhere.

Fast and sensitive method for detecting volatile species in liquids

Science.gov (United States)

Trimarco, Daniel B.; Pedersen, Thomas; Hansen, Ole; Chorkendorff, Ib; Vesborg, Peter C. K.

2015-07-01

This paper presents a novel apparatus for extracting volatile species from liquids using a "sniffer-chip." By ultrafast transfer of the volatile species through a perforated and hydrophobic membrane into an inert carrier gas stream, the sniffer-chip is able to transport the species directly to a mass spectrometer through a narrow capillary without the use of differential pumping. This method inherits features from differential electrochemical mass spectrometry (DEMS) and membrane inlet mass spectrometry (MIMS), but brings the best of both worlds, i.e., the fast time-response of a DEMS system and the high sensitivity of a MIMS system. In this paper, the concept of the sniffer-chip is thoroughly explained and it is shown how it can be used to quantify hydrogen and oxygen evolution on a polycrystalline platinum thin film in situ at absolute faradaic currents down to ˜30 nA. To benchmark the capabilities of this method, a CO-stripping experiment is performed on a polycrystalline platinum thin film, illustrating how the sniffer-chip system is capable of making a quantitative in situ measurement of <1 % of a monolayer of surface adsorbed CO being electrochemically stripped off an electrode at a potential scan-rate of 50 mV s-1.

Biogenic volatile organic compounds from the urban forest of the Metropolitan Region, Chile

International Nuclear Information System (INIS)

Préndez, Margarita; Carvajal, Virginia; Corada, Karina; Morales, Johanna; Alarcón, Francis; Peralta, Hugo

2013-01-01

Tropospheric ozone is a secondary pollutant whose primary sources are volatile organic compounds and nitrogen oxides. The national standard is exceeded on a third of summer days in some areas of the Chilean Metropolitan Region (MR). This study reports normalized springtime experimental emissions factors (EF) for biogenic volatile organic compounds from tree species corresponding to approximately 31% of urban trees in the MR. A Photochemical Ozone Creation Index (POCI) was calculated using Photochemical Ozone Creation Potential of quantified terpenes. Ten species, natives and exotics, were analysed using static enclosure technique. Terpene quantification was performed using GC-FID, thermal desorption, cryogenic concentration and automatic injection. Observed EF and POCI values for terpenes from exotic species were 78 times greater than native values; within the same family, exotic EF and POCI values were 28 and 26 times greater than natives. These results support reforestation with native species for improved urban pollution management. -- First experimental determination of the emission factors of biogenic volatile organic compounds in the urban forest of the Metropolitan Region, Chile

Characterization of Crew Refuse Returned from Shuttle Missions with Permanent Gas, Volatile Organic Compound, and Microbial Analyses

Science.gov (United States)

Peterson, B.; Hummerick, M.; Roberts, M.; Krummins, V.; Kish, A.; Garland, J.; Maxwell, S.; Mills, A.

In addition to the mass and energy costs associated with bioregenerative systems for advanced life support, the storage and processing of waste on spacecraft requires both atmospheric and biological management. Risks to crew health may arise from the presence of potential human pathogens in waste or from decay processes during waste storage and/or processing. This study reports on the permanent gas, trace volatile organic and microbiological analyses of crew refuse returned from shuttle missions STS-105, 109 and 110. The research objective is to characterize the biological stability of the waste stream, to assess the risks associated with its storage, and to provide baseline measures for the evaluation of waste processing technologies. Microbiological samples were collected from packaging material, food waste, bathroom waste, and bulk liquid collected from the volume F waste container. The number of culturable bacteria and total bacteria were determined by plating on R2A media and by Acridine Orange direct count, respectively. Samples of the trash were analyzed for the presence of fecal and total coliforms and other human-associated bacteria. Dry and ash weights were determined to estimate both water and organic content of the materials. The aerobic and anaerobic bio-stability of stored waste was determined by on-line monitoring of CO2 and by laboratory analysis of off-gas samples for hydrogen sulfide and methane. Volatile organic compounds and permanent gases were analyzed using EPA method TO15 with gas chromatography/mass spectrometry and by gas chromatography with selective detectors . This study establishes a baseline measure of waste composition, labile organics, and microbial load for this material.

40 CFR Table 2 to Subpart II of... - Volatile Organic HAP (VOHAP) Limits for Marine Coatings

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Volatile Organic HAP (VOHAP) Limits... (Surface Coating) Pt. 63, Subpt. II, Table 2 Table 2 to Subpart II of Part 63—Volatile Organic HAP (VOHAP...) through (4). b VOC (including exempt compounds listed as HAP) shall be used as a surrogate for VOHAP for...

The fight against Volatile Organic Compounds (VOC)

International Nuclear Information System (INIS)

Anon.

1993-01-01

This paper strikes the balance of the fight against organic volatile compounds emissions in France and in Europe. The first part describes the influence of VOC on production of Ozone in troposphere and gives numerical data on permissive emission values in atmosphere. The second part describes french and european policy and regulations. The third part gives the principle methods and devices for COV measurement in the atmosphere. In the last part, effluents treatment is given: thermal incineration, catalytic incineration, adsorption on active carbon, biologic purification, condensation and separative processes on membrane

Beyond the network of plants volatile organic compounds

OpenAIRE

Vivaldo, Gianna; Masi, Elisa; Taiti, Cosimo; Caldarelli, Guido; Mancuso, Stefano

2017-01-01

Plants emission of volatile organic compounds (VOCs) is involved in a wide class of ecological functions, as VOCs play a crucial role in plants interactions with biotic and abiotic factors. Accordingly, they vary widely across species and underpin differences in ecological strategy. In this paper, VOCs spontaneously emitted by 109 plant species (belonging to 56 different families) have been qualitatively and quantitatively analysed in order to classify plants species. By using bipartite netwo...

Ionic liquid-based air-assisted liquid-liquid microextraction followed by high performance liquid chromatography for the determination of five fungicides in juice samples.

Science.gov (United States)

You, Xiangwei; Chen, Xiaochu; Liu, Fengmao; Hou, Fan; Li, Yiqiang

2018-01-15

A novel and simple ionic liquid-based air-assisted liquid-liquid microextraction technique combined with high performance liquid chromatography was developed to analyze five fungicides in juice samples. In this method, ionic liquid was used instead of a volatile organic solvent as the extraction solvent. The emulsion was formed by pulling in and pushing out the mixture of aqueous sample solution and extraction solvent repeatedly using a 10mL glass syringe. No organic dispersive solvent was required. Under the optimized conditions, the limits of detection (LODs) were 0.4-1.8μgL -1 at a signal-to-noise ratio of 3. The limits of quantification (LOQs) set as the lowest spiking levels with acceptable recovery in juices were 10μgL -1 , except for fludioxonil whose LOQ was 20μgL -1 . The proposed method was applied to determine the target fungicides in juice samples, and acceptable recoveries ranging from 74.9% to 115.4% were achieved. Copyright © 2017. Published by Elsevier Ltd.

Polish and Silesian Non-Profit Organizations Liquidity Strategies

Directory of Open Access Journals (Sweden)

Grzegorz Michalski

2011-12-01

Full Text Available The kind of realized mission inflows the sensitivity to risk. Among other factors, the risk results from decision about liquid assets investment level and liquid assets financing. The higher the risk exposure, the higher the level of liquid assets. If the specific risk exposure is smaller, the more aggressive could be the net liquid assets strategy. The organization choosing between various solutions in liquid assets needs to decide what level of risk is acceptable for her owners (or donors and / or capital suppliers. The paper shows how, in authors opinion, decisions, about liquid assets management strategy inflow the risk of the organizations and its economicalresults during realization of main mission. Comparison of theoretical model with empirical data for over 450 Silesian nonprofit organization results suggests that nonprofit organization managing teams choose more risky aggressive liquid assets solutions than for-profit firms.

IMPROVED SYNTHESIS OF ROOM TEMPERATURE IONIC LIQUIDS

Science.gov (United States)

Room temperature ionic liquids (RTILs), molten salts comprised of N-alkylimidazolium cations and various anions, have received significant attention due to their commercial potential in a variety of chemical applications especially as substitutes for conventional volatile organic...

Studies of volatiles and organic materials in early terrestrial and present-day outer solar system environments

Science.gov (United States)

Sagan, Carl; Thompson, W. Reid; Chyba, Christopher F.; Khare, B. N.

1991-01-01

A review and partial summary of projects within several areas of research generally involving the origin, distribution, chemistry, and spectral/dielectric properties of volatiles and organic materials in the outer solar system and early terrestrial environments are presented. The major topics covered include: (1) impact delivery of volatiles and organic compounds to the early terrestrial planets; (2) optical constants measurements; (3) spectral classification, chemical processes, and distribution of materials; and (4) radar properties of ice, hydrocarbons, and organic heteropolymers.

Novel collection method for volatile organic compounds (VOCs) from dogs

Science.gov (United States)

Host derived chemical cues are an important aspect of arthropod attraction to potential hosts. Host cues that act over longer distances include CO2, heat, and water vapor, while cues such as volatile organic compounds (VOCs) act over closer distances. Domestic dogs are important hosts for disease cy...

A method for the combined measurement of volatile and condensable organic AMC in semiconductor applications

Science.gov (United States)

Miller, Charles M.; Zaloga, Emily C.; Lobert, Jürgen M.

2014-04-01

Monitoring airborne molecular contamination (AMC) at the parts per trillion (ppt) level in cleanroom environments, scanner applications and compressed gas lines is essential for processes, equipment and yield-control. For the operation of EUV tools, in particular, volatile organic contamination is known to have as much impact as condensable organic compounds, which requires a suitable sampling and measurement methodology. Some of the current industry standards use sample traps comprised of porous 2,6-diphenylene-oxide polymer resin, such as Tenax®, for measuring volatile organic (6 C atoms, about toluene and higher) AMC. Inherent problems associated with these traps are a number of artifacts and chemical reactions that reduce accuracy of reported organic AMC concentrations. The break-down of the polymeric material forms false positive artifacts when used in the presence of reactive gases, such as nitrous acid and ozone, which attack and degrade the polymer to form detectable AMC. Most importantly, these traps have poor capture efficiency for volatile organic compounds (VOC). To address the disadvantages of polymer-based sample traps, we developed a method based on carbonaceous, multi-layered adsorbent traps to replace the 2,6-diphenylene-oxide polymer resin sample trap type. Along with the new trap's ability to retain volatile organics, the trap was found to provide artifact-free results. With industry trends towards detecting more contaminants while continuously reducing required reporting limits for those compounds, artifact-free and accurate detection of AMC is needed at the parts per quadrillion (ppq) level. The proposed, multi-layered trap substantially increases laboratory productivity and reduces cost by eliminating the need to analyze condensable and volatile organic compounds in two separate methods. In our studies, even some organic compounds with six C-atoms, that are part of exposure tool OEM requirements, were not effectively retained by polymeric

Volatile organic compounds and Photobacterium phosphoreum associated with spoilage of modified-atmosphere-packaged raw pork

DEFF Research Database (Denmark)

Nieminen, Timo T.; Dalgaard, Paw; Björkroth, Johanna

2016-01-01

Accumulation of volatile organic compounds was monitored in association with sensory quality, bacterial concentrations and culture-independent microbial community analyses in raw pork loin and pork collar during storage under high-oxygen modified atmosphere at +4°C. Of the 48 volatile compounds...

Use of diatomaceous to liquid organic wastes adsorption

International Nuclear Information System (INIS)

Sanhueza M, Azucena; Padilla S, Ulises

1999-01-01

Background: One of the radioactive wastes that the Radioactive Wastes Management Unit must process are organic liquids from external generators and from sections of the Chilean Nuclear Energy Commission (CCHEN). The wastes from external generators contain H 3 and C 14; while the wastes from the CCHEN are contaminated with uranium. The total volume of liquid organic wastes that must be treated is 5 m3. The options recommended for processing these wastes are incineration or the adsorption of the organic liquid by some adsorbing medium and its subsequent immobilization in cement molds. Due to the cost of incineration, the adsorption method was chosen for study. Objective: To find the optimum amount of adsorbent to be saturated with radioactive organic liquid from liquid scintillation and to study immobilization in cement molds. Methodology: Adsorption granulated (1568 Merck) and diatom earth were tested as adsorbent mediums. The adsorbents were mixed in different ratios of volume with the organic liquid. Then the waste was mixed with different water/cement ratios to define the best immobilization conditions. Conclusions: The tests carried out with 2 adsorbents recommended in the literature and available in the CCHEN show that as adsorbent waste ratio decreases, the percentage of liquid adsorbed increases, as expected: a greater volume of adsorbent retains a greater quantity of liquid, with an increase in the final volume, depending on the adsorbent used. Of these adsorbents, the diatom earth was better for treating liquid organic wastes. It had 100% adsorption and an increased volume of 0%, which is more than enough from the volumetric point of view of waste management. The ratio 0.8 liquid/adsorbent also showed good characteristics, but more study is needed to decide on the above, since liquid remains to be adsorbed. This work must continue to study the repeatability of results, to obtain physical and radiological characteristics for the immobilized products and to

Volatile and intermediate volatility organic compounds in suburban Paris: variability, origin and importance for SOA formation

International Nuclear Information System (INIS)

Ait-Helal, W.; Borbon, A.; Beekmann, M.; Doussin, J.F.; Durand-Jolibois, R.; Grand, N.; Michoud, V.; Miet, K.; Perrier, S.; Siour, G.; Zapf, P.; Sauvage, S.; Fronval, I.; Leonardis, T.; Locoge, N.; Gouw, J.A. de; Colomb, A.; Gros, V.; Lopez, M.

2014-01-01

Measurements of gaseous and particulate organic carbon were performed during the MEGAPOLI experiments, in July 2009 and January-February 2010, at the SIRTA observatory in suburban Paris. Measurements comprise primary and secondary volatile organic compounds (VOCs), of both anthropogenic and biogenic origins, including C12-C16 n-alkanes of intermediate volatility (IVOCs), suspected to be efficient precursors of secondary organic aerosol (SOA). The time series of gaseous carbon are generally consistent with times series of particulate organic carbon at regional scale, and are clearly affected by meteorology and air mass origin. Concentration levels of anthropogenic VOCs in urban and suburban Paris were surprisingly low (2-963 ppt) compared to other mega-cities worldwide and to rural continental sites. Urban enhancement ratios of anthropogenic VOC pairs agree well between the urban and suburban Paris sites, showing the regional extent of anthropogenic sources of similar composition. Contrary to other primary anthropogenic VOCs (aromatics and alkanes), IVOCs showed lower concentrations in winter (≤ 5 ppt) compared to summer (13-27 ppt), which cannot be explained by the gas-particle partitioning theory. Higher concentrations of most oxygenated VOCs in winter (18-5984 ppt) suggest their dominant primary anthropogenic origin. The respective role of primary anthropogenic gaseous compounds in regional SOA formation was investigated by estimating the SOA mass concentration expected from the anthropogenic VOCs and IVOCs (I/VOCs) measured at SIRTA. From an integrated approach based on emission ratios and SOA yields, 38% of the SOA measured at SIRTA is explained by the measured concentrations of I/VOCs, with a 2% contribution by C12-C16 n-alkane IVOCs. From the results of an alternative time-resolved approach, the average IVOC contribution to SOA formation is estimated to be 7 %, which is half of the average contribution of the traditional aromatic compounds (15 %). Both

Control of postharvest Botrytis fruit rot of strawberry by volatile organic compounds of Candida intermedia.

Science.gov (United States)

Huang, R; Li, G Q; Zhang, J; Yang, L; Che, H J; Jiang, D H; Huang, H C

2011-07-01

A study was conducted to identify volatile organic compounds or volatiles produced by Candida intermedia strain C410 using gas chromatography-mass spectrometry, and to determine efficacy of the volatiles of C. intermedia in suppression of conidial germination and mycelial growth of Botrytis cinerea and control of Botrytis fruit rot of strawberry. Results showed that, among 49 volatiles (esters, alcohols, alkenes, alkanes, alkynes, organic acids, ketones, and aldehydes) identified from C. intermedia cultures on yeast extract peptone dextrose agar, two compounds, 1,3,5,7-cyclooctatetraene and 3-methyl-1-butanol, were the most abundant. Synthetic chemicals of 1,3,5,7-cyclooctatetraene; 3-methyl-1-butanol; 2-nonanone; pentanoic acid, 4-methyl-, ethyl ester; 3-methyl-1-butanol, acetate; acetic acid, pentyl ester; and hexanoic acid, ethyl ester were highly inhibitory to conidial germination and mycelial growth of B. cinerea. Inhibition of conidial germination and mycelial growth of B. cinerea by volatiles of C. intermedia was also observed. Meanwhile, results showed that incidence and severity of Botrytis fruit rot of strawberry was significantly (P intermedia cultures or C. intermedia-infested strawberry fruit. These results suggest that the volatiles of C. intermedia C410 are promising biofumigants for control of Botrytis fruit rot of strawberry.

Factors that influence the volatile organic compound content in human breath

NARCIS (Netherlands)

Blanchet, L.; Smolinska, Agnieszka; Baranska, Agnieszka; Tigchelaar-Feenstra, E.; Swertz, M.; Zhernakova, A.; Dallinga, J. W.; Wijmenga, C.; van Schooten, Frederik J.

Background. Thousands of endogenous and exogenous volatile organic compounds (VOCs) are excreted in each breath. Inflammatory and deviant metabolic processes affect the level of endogeneous VOCs, which can serve as specific biomarkers for clinical diagnosis and disease monitoring. Important issues

Volatile Organic Sulfur Compounds of Environmental Interest: Dimethyl Sulfide and Methanethiol

Science.gov (United States)

Chasteen, Thomas G.; Bentley, Ronald

2004-01-01

Volatile organic sulfur compounds (VOSCs) have been assigned environmental roles in global warming, acid precipitation, and cloud formation where two important members dimethyl sulfide (CH3)2 S, DMS, and methanethiol, CH3SH, MT, of VOSC group are involved.

Electrospun Polyurethane Fibers for Absorption of Volatile Organic Compounds from Air

NARCIS (Netherlands)

Scholten, E.; Bromberg, L.; Rutledge, G.C.; Hatton, T.A.

2011-01-01

Electrospun polyurethane fibers for removal of volatile organic compounds (VOC) from air with rapid VOC absorption and desorption have been developed. Polyurethanes based on 4,4-methylenebis(phenylisocyanate) (MDI) and aliphatic isophorone diisocyanate as the hard segments and butanediol and

Scalable printed electronics: an organic decoder addressing ferroelectric non-volatile memory

Science.gov (United States)

Ng, Tse Nga; Schwartz, David E.; Lavery, Leah L.; Whiting, Gregory L.; Russo, Beverly; Krusor, Brent; Veres, Janos; Bröms, Per; Herlogsson, Lars; Alam, Naveed; Hagel, Olle; Nilsson, Jakob; Karlsson, Christer

2012-01-01

Scalable circuits of organic logic and memory are realized using all-additive printing processes. A 3-bit organic complementary decoder is fabricated and used to read and write non-volatile, rewritable ferroelectric memory. The decoder-memory array is patterned by inkjet and gravure printing on flexible plastics. Simulation models for the organic transistors are developed, enabling circuit designs tolerant of the variations in printed devices. We explain the key design rules in fabrication of complex printed circuits and elucidate the performance requirements of materials and devices for reliable organic digital logic. PMID:22900143

Emerging site characterization technologies for volatile organic compounds

International Nuclear Information System (INIS)

Rohay, V.J.; Last, G.V.

1992-05-01

A Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) expedited response action (ERA) has been initiated at Hanford Site's 200 West Area for the removal of carbon tetrachloride from the unsaturated soils. In coordination with the ERA, innovative technology demonstrations are being conducted as part of DOE's Volatile Organic Compounds -- Arid Integrated Demonstration in an effort to improve upon baseline technologies. Improved methods for accessing, sampling, and analyzing soil and soil-vapor contaminants is a high priority. Sonic drilling is being evaluated as an alternative to cable-tool drilling, while still providing the advantages of reliability, containment, and waste minimization. Applied Research Associates, Inc. used their cone penetrometer in the 200 West Area to install a permanent soil-gas monitoring probe and to collect soil-gas profile data. However, successful application of this technology will require the development of an improved ability to penetrate coarse gravel units. A Science and Engineering Associates Membrane Instrumentation and Sampling Technique (SEAMIST) system designed for collecting in situ soil samples and air permeability data in between drilling runs at variable depths is being tested in 200 West Area boreholes. Analytical technologies scheduled for testing include supercritical fluid extraction and analysis for non- and semi-volatile organic co-contaminants and an unsaturated flow apparatus developed by Washington State University for the measurement of transport parameters

Volatile compounds emitted by diverse phytopathogenic microorganisms promote plant growth and flowering through cytokinin action

Czech Academy of Sciences Publication Activity Database

Sanchez-Lopez, A.; Baslam, M.; De Diego, N.; Jose Munoz, F.; Bahaji, A.; Almagro, G.; Ricarte-Bermejo, A.; Garcia-Gomez, P.; Li, J.; Humplík, J.F.; Novák, Ondřej; Spíchal, L.; Doležal, Karel; Baroja-Fernandez, E.; Pozueta-Romero, J.

2016-01-01

Roč. 39, č. 12 (2016), s. 2592-2608 ISSN 0140-7791 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : exceptionally high-levels * tandem mass-spectrometry * arabidopsis-thaliana * nitric-oxide * bacterial volatiles * floral transition * anthocyanin biosynthesis * transgenic arabidopsis * liquid-chromatography * organic-compounds * cytokinin * flowering * growth promotion * microbial volatile compounds * photoregulation * photosynthesis * plant-microbe interaction * starch Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 6.173, year: 2016

Ionic liquids: an x-ray reflectivity study

International Nuclear Information System (INIS)

Sloutskin, E.; Deutsch, M.; Tamam, L.; Ocko, B.; Kuzmenko, I.; Gog, T.

2005-01-01

Full Text:Ionic liquids are non-volatile, non-flammable and thermally stable solvents, and as such are promising 'green' replacements for traditional volatile organic solvents. In the last years hundreds of Ionic liquids were synthesized. Due to the Ionic liquids great industrial potential, this number is growing at an exceedingly fast rate. Despite the great importance of the interfacial properties of materials for technological applications and basic science, the atomic-scale surface structure of the Ionic liquids has never been studied previously. In our study, synchrotron x-ray reflectivity and surface tensiometry were employed to obtain the surface structure and thermodynamics of two ionic liquids, based on the 1-alkyl-3-methylimidazolium cations. A molecular layer of a density ∼18% higher than that of the bulk is found to form at the free surface of these liquids. The excess concentration of the oppositely charged ions within the surface layer is determined by chemical substitution of the anion. Finally, the observed layering at the surface is contrasted with our measurements on the behavior of classical aqueous salt solutions

High-yield exfoliation of graphene using ternary-solvent strategy for detecting volatile organic compounds

Science.gov (United States)

Zhang, Shao-Lin; Zhang, Zhijun; Yang, Woo-Chul

2016-01-01

Despite the great progress in the theory and experimental verification we made in past decade, the practical application of graphene is still hindered by the lack of efficient, economical, scalable, ease-processing exfoliation method. Herein, we propose a facile, low-cost, and efficient liquid-phase exfoliation process using low boiling-temperature solvent mixture to fabricate few-layer graphene in large scale. The Hansen solubility parameter theory was applied to help optimize the composition of solvent mixture. Aqueous-based ternary-solvent mixture, for the first time, was adapted to exfoliate graphene. We demonstrate that the exfoliation efficiency using ternary-solvent mixture surpasses that from binary-solvent approach. The final product concentration after optimization was over 260 μg/ml. The concentrated graphene dispersion was used to fabricate gas sensor for detecting volatile organic gases. Taking advantage of large surface area, large number of adsorption sites, and well-preserved basal plane, the mass-produced graphene nanosheets exhibited promising sensing potential toward ethanol and methanol vapors.

Liquid-liquid extraction of plutonium(IV) in monoamide - ammonium ionic liquid mixture

International Nuclear Information System (INIS)

Rout, Alok; Venkatesan, K.A.; Antony, M.P.

2016-01-01

Room temperature ionic liquid (RTIL) can be regarded as a sustainable alternative to the conventional molecular diluent, n-dodecane (n-DD), in solvent extraction process. Replacement of volatile organic solvents by RTILs in solvent extraction could lead to inherently safer processes. As far as the cation is concerned, most of the studies reported in literature are focused on imidazolium-based ionic liquids. In contrast to imiadazolium ionic liquids, quarternary ammonium ionic liquids like trioctylmethylammonium chloride (Aliquat 336), trioctylmethylammonium nitrate etc., do not exhibit any cation exchange with the metal ions from aqueous phase during extraction. However, there is no report available in literature that emphasizes the application of trioctylmethylammonium bis(trifluoromethane-sulfonyl)imide ((N_1_8_8_8)(NTf_2)) ionic liquid, for the extraction of Pu(IV). In this paper, we report the advantages of using the ionic liquid, trioctylmethylammonium bis(trifluoromethanesulfonyl)imide ((N_1_8_8_8)(NTf_2)), as diluent, for the extraction of plutonium(IV) in DHOA/(N_1_8_8_8)(NTf_2)

Reactive oxidation products promote secondary organic aerosol formation from green leaf volatiles

Directory of Open Access Journals (Sweden)

J. F. Hamilton

2009-06-01

Full Text Available Green leaf volatiles (GLVs are an important group of chemicals released by vegetation which have emission fluxes that can be significantly increased when plants are damaged or stressed. A series of simulation chamber experiments has been conducted at the European Photoreactor in Valencia, Spain, to investigate secondary organic aerosol (SOA formation from the atmospheric oxidation of the major GLVs cis-3-hexenylacetate and cis-3-hexen-1-ol. Liquid chromatography-ion trap mass spectrometry was used to identify chemical species present in the SOA. Cis-3-hexen-1-ol proved to be a more efficient SOA precursor due to the high reactivity of its first generation oxidation product, 3-hydroxypropanal, which can hydrate and undergo further reactions with other aldehydes resulting in SOA dominated by higher molecular weight oligomers. The lower SOA yields produced from cis-3-hexenylacetate are attributed to the acetate functionality, which inhibits oligomer formation in the particle phase. Based on observed SOA yields and best estimates of global emissions, these compounds may be calculated to be a substantial unidentified global source of SOA, contributing 1–5 TgC yr⁻¹, equivalent to around a third of that predicted from isoprene. Molecular characterization of the SOA, combined with organic mechanistic information, has provided evidence that the formation of organic aerosols from GLVs is closely related to the reactivity of their first generation atmospheric oxidation products, and indicates that this may be a simple parameter that could be used in assessing the aerosol formation potential for other unstudied organic compounds in the atmosphere.

Total Oxidation of Model Volatile Organic Compounds over Some Commercial Catalysts

Czech Academy of Sciences Publication Activity Database

Matějová, Lenka; Topka, Pavel; Jirátová, Květa; Šolcová, Olga

2012-01-01

Roč. 443, NOV 7 (2012), s. 40-49 ISSN 0926-860X R&D Projects: GA MPO FR-TI1/059 Institutional support: RVO:67985858 Keywords : volatile organic compounds * oxidation * ethanol Subject RIV: DM - Solid Waste and Recycling Impact factor: 3.410, year: 2012

Volatile chemical products emerging as largest petrochemical source of urban organic emissions

Science.gov (United States)

McDonald, Brian C.; de Gouw, Joost A.; Gilman, Jessica B.; Jathar, Shantanu H.; Akherati, Ali; Cappa, Christopher D.; Jimenez, Jose L.; Lee-Taylor, Julia; Hayes, Patrick L.; McKeen, Stuart A.; Cui, Yu Yan; Kim, Si-Wan; Gentner, Drew R.; Isaacman-VanWertz, Gabriel; Goldstein, Allen H.; Harley, Robert A.; Frost, Gregory J.; Roberts, James M.; Ryerson, Thomas B.; Trainer, Michael

2018-02-01

A gap in emission inventories of urban volatile organic compound (VOC) sources, which contribute to regional ozone and aerosol burdens, has increased as transportation emissions in the United States and Europe have declined rapidly. A detailed mass balance demonstrates that the use of volatile chemical products (VCPs)—including pesticides, coatings, printing inks, adhesives, cleaning agents, and personal care products—now constitutes half of fossil fuel VOC emissions in industrialized cities. The high fraction of VCP emissions is consistent with observed urban outdoor and indoor air measurements. We show that human exposure to carbonaceous aerosols of fossil origin is transitioning away from transportation-related sources and toward VCPs. Existing U.S. regulations on VCPs emphasize mitigating ozone and air toxics, but they currently exempt many chemicals that lead to secondary organic aerosols.

Applications of Ionic Liquids in Electrochemical Sensors and Biosensors

Directory of Open Access Journals (Sweden)

Virendra V. Singh

2012-01-01

Full Text Available Ionic liquids (ILs are salt that exist in the liquid phase at and around 298 K and are comprised of a bulky, asymmetric organic cation and the anion usually inorganic ion but some ILs also with organic anion. ILs have attracted much attention as a replacement for traditional organic solvents as they possess many attractive properties. Among these properties, intrinsic ion conductivity, low volatility, high chemical and thermal stability, low combustibility, and wide electrochemical windows are few. Due to negligible or nonzero volatility of these solvents, they are considered “greener” for the environment as they do not evaporate like volatile organic compounds (VOCs. ILs have been widely used in electrodeposition, electrosynthesis, electrocatalysis, electrochemical capacitor, lubricants, plasticizers, solvent, lithium batteries, solvents to manufacture nanomaterials, extraction, gas absorption agents, and so forth. Besides a brief discussion of the introduction, history, and properties of ILs the major purpose of this review paper is to provide an overview on the advantages of ILs for the synthesis of conducting polymer and nanoparticle when compared to conventional media and also to focus on the electrochemical sensors and biosensors based on IL/composite modified macrodisk electrodes. Subsequently, recent developments and major strategies for enhancing sensing performance are discussed.

The development and testing of a volatile organics concentrator for use in monitoring Space Station water quality

Science.gov (United States)

Bodek, Itamar; Ehntholt, Daniel J.; Stolki, Thomas J.; Trabanino, Rudy; Hinsdale, Lloyd; Webb, Johanna; Sauer, Richard L.

1992-01-01

The Volatile Organics Concentrator (VOC) system, designed to attach to a gas chromatograph/mass spectrometer (GC/MS) for the analyses of volatile organic compounds in water on Space Station Freedom, is described. Organic volatiles are collected and concentrated in the VOC by means of two primary solid sorbent tubes and desorbed into the GC/MS system. The paper describes the results of testing the VOC breadboard using a GC/MS system. Evaluations performed on 39 organic compounds recovered from water samples were compared with data for these compounds using direct injection/GC/MS and purge and trap/GC/MS procedures. The results demonstrate that the VOC/GC/MS system's detection limits for the 39 compounds analyzed are comparable to those of the EPA Method 524.2, and for many compounds reaching a factor of 5 lower.

Electron donation characteristics and interplays of major volatile fatty acids from anaerobically fermented organic matters in bioelectrochemical systems.

Science.gov (United States)

Zhang, Zhiqiang; Li, Jiamiao; Hao, Xiaoxuan; Gu, Zaoli; Xia, Siqing

2018-02-23

Anaerobic fermentation liquid of waste organic matters (WOMs) is rich in volatile fatty acids (VFAs), which can be treated with bioelectrochemical systems for both electrical energy recovery and organics removal. In this work, four major VFAs in the fermented WOMs supernatant were selected to examine their electron donation characteristics for power output and their complicated interplays in microbial fuel cells (MFCs). Results indicated a priority sequence of acetate, propionate, n-butyrate and i-valerate when served as the sole electron donor for electricity generation. The MFC solely fed with acetate showed the highest coulombic efficiency and power density, and the longest period for electricity production. When two of the VFAs were added with equal proportion, both acids contributed positively to electricity generation, while the selective or competitive use of substrates by diverse microorganisms behaved as an antagonism effect to prolong the degradation time of each VFA. When acetate and propionate, the preferable substrates for electricity generation, were mixed in various proportions, their large concentration difference led to improved electrical performance but decreased organic removal rate.

Oceanic Emissions and Atmospheric Depositions of Volatile Organic Compounds

Science.gov (United States)

Yang, M.; Blomquist, B.; Beale, R.; Nightingale, P. D.; Liss, P. S.

2015-12-01

Atmospheric volatile organic compounds (VOCs) affect the tropospheric oxidative capacity due to their ubiquitous abundance and relatively high reactivity towards the hydroxyal radical. Over the ocean and away from terrestrial emission sources, oxygenated volatile organic compounds (OVOCs) make up a large fraction of VOCs as airmasses age and become more oxidized. In addition to being produced or destroyed in the marine atmosphere, OVOCs can also be emitted from or deposited to the surface ocean. Here we first present direct air-sea flux measurements of three of the most abundant OVOCs - methanol, acetone, and acetaldehyde, by the eddy covariance technique from two cruises in the Atlantic: the Atlantic Meridional Transect in 2012 and the High Wind Gas Exchange Study in 2013. The OVOC mixing ratios were quantified by a high resolution proton-reaction-transfer mass spectrometer with isotopically labeled standards and their air-sea (net) fluxes were derived from the eddy covariance technique. Net methanol flux was consistently from the atmosphere to the surface ocean, while acetone varied from supersaturation (emission) in the subtropics to undersaturation (deposition) in the higher latitudes of the North Atlantic. The net air-sea flux of acetaldehyde is near zero through out the Atlantic despite the apparent supersaturation of this compound in the surface ocean. Knowing the dissolved concentrations and in situ production rates of these compounds in seawater, we then estimate their bulk atmospheric depositions and oceanic emissions. Lastly, we summarize the state of knowledge on the air-sea transport of a number of organic gasses, and postulate the magnitude and environmental impact of total organic carbon transfer between the ocean and the atmosphere.

Oxidation of volatile organic vapours in air by solid potassium permanganate

NARCIS (Netherlands)

Mahmoodlu, M.G.; Hartog, N.; Hassanizadeh, S.M.; Raoof, A.

2013-01-01

Volatile organic compounds (VOCs) may frequently contaminate groundwater and pose threat to human health when migrating into the unsaturated soil zone and upward to the indoor air. The kinetic of chemical oxidation has been investigated widely for dissolved VOCs in the saturated zone. But, so far

The scent of colorectal cancer: detection by volatile organic compound analysis

NARCIS (Netherlands)

de Boer, Nanne K. H.; de Meij, Tim G. J.; Oort, Frank A.; Ben Larbi, Ilhame; Mulder, Chris J. J.; van Bodegraven, Adriaan A.; van der Schee, Marc P.

2014-01-01

The overall metabolic state of an individual is reflected by emitted volatile organic compounds (VOCs), which are gaseous carbon-based chemicals. In this review, we will describe the potential of VOCs as fully noninvasive markers for the detection of neoplastic lesions of the colon. VOCs are

Nanoparticles in ionic liquids: interactions and organization.

Science.gov (United States)

He, Zhiqi; Alexandridis, Paschalis

2015-07-28

Ionic liquids (ILs), defined as low-melting organic salts, are a novel class of compounds with unique properties and a combinatorially great chemical diversity. Ionic liquids are utilized as synthesis and dispersion media for nanoparticles as well as for surface functionalization. Ionic liquid and nanoparticle hybrid systems are governed by a combined effect of several intermolecular interactions between their constituents. For each interaction, including van der Waals, electrostatic, structural, solvophobic, steric, and hydrogen bonding, the characterization and quantitative calculation methods together with factors affecting these interactions are reviewed here. Various self-organized structures based on nanoparticles in ionic liquids are generated as a result of a balance of these intermolecular interactions. These structures, including colloidal glasses and gels, lyotropic liquid crystals, nanoparticle-stabilized ionic liquid-containing emulsions, ionic liquid surface-functionalized nanoparticles, and nanoscale ionic materials, possess properties of both ionic liquids and nanoparticles, which render them useful as novel materials especially in electrochemical and catalysis applications. This review of the interactions within nanoparticle dispersions in ionic liquids and of the structure of nanoparticle and ionic liquid hybrids provides guidance on the rational design of novel ionic liquid-based materials, enabling applications in broad areas.

Volatiles from solids

Energy Technology Data Exchange (ETDEWEB)

Loughrey, C T

1939-08-24

To remove volatiles from solids, such as oil shale, gases, and/or vapours are passed through a mass of the materials, the vapours and gases separated, and the vapours condensed. The volatile-containing solid materials are fed to a retort, and a shaft is driven to rotate an impeller so as to displace the liquid and create a vortex tube, which draws in gas from the atmosphere through an intake, twyer, interstices in the material in the retort, a conduit, chamber, tubes, another chamber and cylinder. This gas is carried outwardly and upwardly by the vortices in the liquid and is carried to discharge through three conduits. The vapours entrained by the gas are part condensed in the liquid and the remainder directed to a condenser. Steam may be delivered to the twyer through a nozzle of a pipe, with or without air, and combustible hydrocarbon fuel may be fed through the burner nozzle or solid fuel may be directed from feeder and combusted in the twyer.

Reclamation of heavy metals from contaminated soil using organic acid liquid generated from food waste: removal of Cd, Cu, and Zn, and soil fertility improvement.

Science.gov (United States)

Dai, Shijin; Li, Yang; Zhou, Tao; Zhao, Youcai

2017-06-01

Food waste fermentation generates complicated organic and acidic liquids with low pH. In this work, it was found that an organic acid liquid with pH 3.28 and volatile low-molecular-weight organic acid (VLMWOA) content of 5.2 g/L could be produced from food wastes after 9-day fermentation. When the liquid-to-solid ratio was 50:1, temperature was 40 °C, and contact time was 0.5-1 day, 92.9, 78.8, and 52.2% of the Cd, Cu, and Zn in the contaminated soil could be washed out using the fermented food waste liquid, respectively. The water-soluble, acid-soluble, and partly reducible heavy metal fractions can be removed after 0.5-day contact time, which was more effective than that using commercially available VLMWOAs (29-72% removal), as the former contained microorganisms and adequate amounts of nutrients (nitrogen, phosphorous, and exchangeable Na, K, and Ca) which favored the washing process of heavy metals. It is thus suggested that the organic acid fractions from food waste has a considerable potential for reclaiming contaminated soil while improving soil fertility.

Carbon tetrachloride contamination, 200 West Area, Hanford Site: Arid Site Integrated Demonstration for remediation of volatile organic compounds

International Nuclear Information System (INIS)

Last, G.V.; Rohay, V.J.

1991-01-01

The Arid State Integrated Demonstration is a US Department of Energy (DOE) program targeted at the acquisition, development, demonstration, and deployment of technologies for evaluation and cleanup of volatile organic and associated contaminants in soils and ground waters. Several DOE laboratories, universities, and industry will participate in the program. Candidate technologies will be demonstrated in the areas of site characterization; performance prediction, monitoring, and evaluations; contaminant extraction and ex situ treatment; in situ remediations; and site closure and monitoring. The performance of these demonstrated technologies will be compared to baseline technologies and documented to promote the transfer of new technologies to industry for use at DOE facilities. The initial host site is the Hanford Site's 200 West Area. The location of the demonstration contains primarily carbon tetrachloride (CCl 4 ), chloroform, and a variety of associated mixed waste contaminants. Chemical processes used to recover and purify plutonium at Hanford's plutonium finishing plant (Z Plant) resulted in the production of actinide-bearing waste liquid. Both aqueous and organic liquid wastes were generated, and were routinely discharged to subsurface disposal facilities. The primary radionuclide in the waste streams was plutonium, and the primary organic was CCl 4 . This paper contains brief descriptions of the principal CCl 4 waste disposal facilities in Hanford's 200 West Area, associated hydrogeology, existing information on the extent of soil and ground-water contamination, and a conceptual outline of suspected subsurface CCl 4 distributions

Transport and Fate of Volatile Organic Chemical in Soils

DEFF Research Database (Denmark)

Petersen, Lis Wollesen

Recently much attention has been paid to the behavior of volatile organic chemicals (VOCs) in the environment. This is due to the fact that the environmental pollution with these hazardous chemicals has drastically increased during the last decades. The present study is limited to consider...... the transport and fate of VOCs in the gaseous phase, thus contributing to the overall understanding of VOCs behavior in soil, which eventually will facilitate future cleanup....

Factors Effecting the Total Volatile Organic Compound (TVOC Concentrations in Slovak Households

Directory of Open Access Journals (Sweden)

Ľudmila Mečiarová

2017-11-01

Full Text Available Thirty five Slovak households were selected for an investigation of indoor environmental quality. Measuring of indoor air physical and chemical factors and a questionnaire survey was performed during May 2017. The range of permissible operative temperature was not met in 11% of objects. Relative humidity met the legislative requirements in all monitored homes. Concentrations of total volatile organic compounds (TVOCs were significantly higher in the apartments than in the family houses. The average TVOC levels in the apartments and family houses were 519.7 µg/m3 and 330.2 µg/m3, respectively. Statistical analysis confirmed the effect of indoor air temperature, relative humidity and particulate matter (PM0.5 and PM1 on the levels of TVOCs. Higher TVOC levels were observed also in homes where it is not a common practice to open windows during cleaning activities. Other factors that had a statistically significant effect on concentrations of volatile organic compounds were heating type, attached garage, location of the apartment within residential building (the floor, as well as number of occupants. Higher TVOC concentrations were observed in indoor than outdoor environment, while further analysis showed the significant impact of indoor emission sources on the level of these compounds in buildings. The questionnaire study showed a discrepancy between objective measurement and subjective assessment in the household environment, and pointed to insufficient public awareness about volatile organic compounds (VOCs.

Global volatile profile of virgin olive oils flavoured by aromatic/medicinal plants.

Science.gov (United States)

Perestrelo, R; Silva, C; Silva, P; Câmara, J S

2017-07-15

The global volatile profile of commercial virgin olive oils and flavoured olive oils with aromatic/medicinal plants, was established using liquid-liquid microextraction (LLME) and headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-quadrupole mass spectrometry (GC-qMS). More than 60 volatile organic compounds (VOCs belonging to different groups were identified using both methods. Olive oils volatile profile was slightly influenced by maceration process, which occurred at room temperature (20±2°C) for 15days. The predominant differences were observed in terpenoids group, since some of them were only identified in the flavoured olive oils, while others showed an increase with the maceration process. VOCs mass transfer from plants to olive oils could explain the observed results. Principal components analysis (PCA) applied to LLME/GC-qMS data allowed to distinguish the olive oils. The flavoured oils would increase the use of olive oil among consumers as consequence of the improvement of its aromatic profile and healthy properties. Copyright © 2017 Elsevier Ltd. All rights reserved.

PERTURBATION OF VOLTAGE-SENSITIVE Ca2+ CHANNEL FUNCTION BY VOLATILE ORGANIC SOLVENTS.

Science.gov (United States)

The mechanisms underlying the acute neurophysiological and behavioral effects of volatile organic compounds (VOCs) remain to be elucidated. However, the function of neuronal ion channels is perturbed by VOCs. The present study examined effects of toluene (TOL), trichloroethylene ...

40 CFR 60.542a - Alternate standard for volatile organic compounds.

Science.gov (United States)

2010-07-01

... PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for the Rubber Tire Manufacturing Industry § 60.542a Alternate standard for volatile organic compounds. (a) On and after the date on which the initial performance test, required by § 60.8, is completed, but no...

Hydrogenation Reactions in Ionic Liquids. The Efficient Reduction of ...

African Journals Online (AJOL)

NJD

2008-12-09

Dec 9, 2008 ... Volatile organic solvents such as ethanol, methanol and THF are often used for the ... remained consistently high and only declined markedly on the fifth cycle. ... transferral of the viscous liquid from the hydrogenation reactor.

Determination of "1"2"9I using volatilization method and liquid scintillation spectrometry

International Nuclear Information System (INIS)

Remenec, Boris; Dulanska, Silvia; Horvathova, Bianka; Matel, Lubomir

2017-01-01

A simple and rapid separation method for "1"2"9I determination in radioactive waste samples was developed. Suitable conditions for iodine volatilization were tested. Iodine was trapped in 1.5 mol L"-"1 NaOH and precipitated as PdI_2·H_2O by addition of PdCl_2 with recoveries higher than 80%. The method was applied for analysis of contaminated soil, radioactive sludge, evaporator concentrate and heterogeneous waste samples from nuclear power plants in Slovak Republic. "1"2"9I was measured on liquid scintillation counter TRI CARB 2900 TR using Ultima Gold AB scintillation cocktail. (author)

Secondary organic aerosol production from pinanediol, a semi-volatile surrogate for first-generation oxidation products of monoterpenes

Science.gov (United States)

Ye, Penglin; Zhao, Yunliang; Chuang, Wayne K.; Robinson, Allen L.; Donahue, Neil M.

2018-05-01

We have investigated the production of secondary organic aerosol (SOA) from pinanediol (PD), a precursor chosen as a semi-volatile surrogate for first-generation oxidation products of monoterpenes. Observations at the CLOUD facility at CERN have shown that oxidation of organic compounds such as PD can be an important contributor to new-particle formation. Here we focus on SOA mass yields and chemical composition from PD photo-oxidation in the CMU smog chamber. To determine the SOA mass yields from this semi-volatile precursor, we had to address partitioning of both the PD and its oxidation products to the chamber walls. After correcting for these losses, we found OA loading dependent SOA mass yields from PD oxidation that ranged between 0.1 and 0.9 for SOA concentrations between 0.02 and 20 µg m-3, these mass yields are 2-3 times larger than typical of much more volatile monoterpenes. The average carbon oxidation state measured with an aerosol mass spectrometer was around -0.7. We modeled the chamber data using a dynamical two-dimensional volatility basis set and found that a significant fraction of the SOA comprises low-volatility organic compounds that could drive new-particle formation and growth, which is consistent with the CLOUD observations.

Salt lakes of Western Australia - Natural abiotic formation of volatile organic compounds

Science.gov (United States)

Krause, T.; Studenroth, S.; Mulder, I.; Tubbesing, C.; Kotte, K.; Ofner, J.; Junkermann, W.; Schöler, H. F.

2012-04-01

Western Australia is a semi-/arid region that is heavily influenced by global climate change and agricultural land use. The area is known for its many ephemeral saline and hypersaline lakes with a wide range of hydrogeochemical parameters that have gradually changed over the last fifty years. Historically, the region was covered by eucalyptus trees and shrubs, but was cleared mainly within 10 years after WWII to make room for wheat and live stock. After the clearance of the deep rooted native plants the groundwater started to rise, bringing increased amounts of dissolved salts and minerals to the surface and discharging them into streams and lakes. Thus most of Western Australia is influenced by secondary salinisation (soil salting) [1]. Another problem is that the discharged minerals affect the pH of ground and surface water, which ranges from acidic to slightly basic. During the 2011 campaign surface water was measured with a pH between 2.5 and 7.1. Another phenomenon in Western Australia is the decrease of rainfall over the last decades assumed to be linked to the secondary salinisation. The rising saline and mineral rich groundwater increases the biotical and abiotical activity of the salt lakes. Halogenated and non-halogenated volatile organic compounds emitted from those lakes undergo fast oxidation and chemical reactions to form small particles modifying cloud microphysics and thus suppressing rain events [2]. Our objective is to gain a better understanding of this extreme environment with its hypersaline acidic lakes with regard to the potential abiotic formation of volatile organic compounds and its impact on the local climate. In spring 2011 fifty-three sediment samples from ten salt lakes in the Lake King region where taken, freeze-dried and ground. In order to simulate the abiotic formation of volatile organic compounds the soil samples were resuspended with water in gas-tight headspace vials. The headspace was measured using a purge and trap GC

Volatile organic chemicals of a shore-dwelling cyanobacterial mat community.

Science.gov (United States)

Evans, W G

1994-02-01

The main components of a cyanobacterial mat community of a hypersaline lake shore consist of edaphic, mat-forming strains (ecophenes), and littoral strains ofOscillatoria animalis Agardh andO. subbrevis Schmidle, other microorganisms associated with these cyanobacteria, several species ofBembidion (Carabidae: Coleoptera), and two halophytic flowering plants:Puccinellia nuttalliana (salt meadow grass) andSalicornia europaea rubra (samphire). The volatile organic compounds of this community are a blend of those emitted by each of these components such as the C17 alka(e)nes, geosmin, 2-methylisoborneol,β-cyclocitral,β-ionone, dimethyl sulfide, and dimethyl trisulfide of cyanobacteria and associated microorganisms; alcohols, esters, and aldehydes usually associated with flowering plants; and possibly some insect-derived esters, particularly isopropyl tetradecanoate. The dominant compounds were: C11, C13, C15, and C17 alka(e)nes, methyl esters of C16 and C18:2 acids, isopropyl tetradecanoate, heptanal, 3-octanone and 2-nonanone, the acyclic terpene linalool, and the alcohols 1-heptanol, 1-hexanol, 1-octanol, 3-hexen-1-ol, and 2-octen-1-ol. It is concluded that this community may be distinguished from related communities by its repertoire of volatile organic compounds.

Description, Properties, and Degradation of Selected Volatile Organic Compounds Detected in Ground Water--A Review of Selected Literature

Science.gov (United States)

Lawrence, Stephen J.

2006-01-01

This report provides abridged information describing the most salient properties and biodegradation of 27 chlorinated volatile organic compounds detected during ground-water studies in the United States. This information is condensed from an extensive list of reports, papers, and literature published by the U.S. Government, various State governments, and peer-reviewed journals. The list includes literature reviews, compilations, and summaries describing volatile organic compounds in ground water. This report cross-references common names and synonyms associated with volatile organic compounds with the naming conventions supported by the International Union of Pure and Applied Chemistry. In addition, the report describes basic physical characteristics of those compounds such as Henry's Law constant, water solubility, density, octanol-water partition (log Kow), and organic carbon partition (log Koc) coefficients. Descriptions and illustrations are provided for natural and laboratory biodegradation rates, chemical by-products, and degradation pathways.

Emission of intermediate, semi and low volatile organic compounds from traffic and their impact on secondary organic aerosol concentrations over Greater Paris

Science.gov (United States)

Sartelet, K.; Zhu, S.; Moukhtar, S.; André, M.; André, J. M.; Gros, V.; Favez, O.; Brasseur, A.; Redaelli, M.

2018-05-01

Exhaust particle emissions are mostly made of black carbon and/or organic compounds, with some of these organic compounds existing in both the gas and particle phases. Although emissions of volatile organic compounds (VOC) are usually measured at the exhaust, emissions in the gas phase of lower volatility compounds (POAvapor) are not. However, these gas-phase emissions may be oxidised after emission and enhance the formation of secondary organic aerosols (SOA). They are shown here to contribute to most of the SOA formation in Central Paris. POAvapor emissions are usually estimated from primary organic aerosol emissions in the particle phase (POA). However, they could also be estimated from VOC emissions for both gasoline and diesel vehicles using previously published measurements from chamber measurements. Estimating POAvapor from VOC emissions and ageing exhaust emissions with a simple model included in the Polyphemus air-quality platform compare well to measurements of SOA formation performed in chamber experiments. Over Greater Paris, POAvapor emissions estimated using POA and VOC emissions are compared using the HEAVEN bottom-up traffic emissions model. The impact on the simulated atmospheric concentrations is then assessed using the Polyphemus/Polair3D chemistry-transport model. Estimating POAvapor emissions from VOC emissions rather than POA emissions lead to lower emissions along motorway axes (between -50% and -70%) and larger emissions in urban areas (up to between +120% and +140% in Central Paris). The impact on total organic aerosol concentrations (gas plus particle) is lower than the impact on emissions: between -8% and 25% along motorway axes and in urban areas respectively. Particle-phase organic concentrations are lower when POAvapor emissions are estimated from VOC than POA emissions, even in Central Paris where the total organic aerosol concentration is higher, because of different assumptions on the emission volatility distribution, stressing the

Measurement and estimated health risks of volatile organic compounds and polychlorinated biphenyls in air at the Hanford Site

International Nuclear Information System (INIS)

Patton, G.W.; Cooper, A.T.; Blanton, M.L.

1994-10-01

A variety of radioactive and nonradioactive chemicals have been released in effluent streams and discharged to waste disposal facilities during the nuclear materials production period at the Hanford Site. Extensive environmental surveillance for radioactive materials has occurred at Hanford; however, only limited information is available on the types and concentrations of organic pollutants potentially present. This report describes work performed to provide the Hanford Site Surface Environmental Surveillance Project with representative air concentration data for volatile organic compounds and polychlorinated biphenyls (PCBs). US Environmental Protection Agency (USEPA) volatile organic compound sampling methods evaluated for Hanford Site use were carbon-based adsorbent traps (TO-2) and Summa air canisters (TO-14). Polychlorinated biphenyls were sampled using USEPA method (TO-4), which uses glass fiber filters and polyurethane foam adsorbent beds to collect the PCBS. This report also presents results for environmental surveillance samples collected for volatile organic compound and PCB analyses from 1990 to 1993. All measured air concentrations of volatile organic compounds and PCBs were well below applicable maximum allowable concentration standards for air contaminants. Because of the lack of ambient air concentration standards, a conservative estimate is provided of the potential human health impacts from exposure to the ambient air concentrations measured on the Hanford Site

Liquid crystalline thermosetting polymers as protective coatings for aerospace

NARCIS (Netherlands)

Guerriero, G.L.

2012-01-01

Environmental regulations are driving the development of new aerospace coating systems, mainly to eliminate chromates and reduce volatile organic compound (VOC) emissions. Among the various potential options for new coating materials, liquid crystalline polymers (LCPs) are attractive due to their

Liquid crystalline thermosetting polymers as protective coatings for aerospace

OpenAIRE

Guerriero, G.L.

2012-01-01

Environmental regulations are driving the development of new aerospace coating systems, mainly to eliminate chromates and reduce volatile organic compound (VOC) emissions. Among the various potential options for new coating materials, liquid crystalline polymers (LCPs) are attractive due to their unique combination of mechanical properties and chemical resistance. Their use, however, has been limited mainly due to poor adhesion properties. Thermotropic liquid crystalline thermosets displayed ...

Distribution of Total Volatile Organic Compounds at taxi drivers in Tehran

Directory of Open Access Journals (Sweden)

Seyyed Mohammad Javad Golhosseini

2015-06-01

Full Text Available Air pollution is currently the most serious environmental health threat worldwide. Volatile Organic Compounds (VOC are considered as the main effective factors in causing air pollution. Vehicles are among the major sources which emit these compounds, so it seems that automobiles’ microenvironment is one of the places where people are exposed to high concentration of VOC. Evaluating the exposure amount of Total Volatile Organic Compounds (TVOC can indeed be used as an indicator to estimate the amount of exposure to every individual VOC. This study was conducted on the concentration of TVOC inside Tehran taxies for a period of one year. For this purpose, a real time instrument equipped with photo-ionization detector (PID was used. Consequently, the highest and the lowest measured TVOC in taxies equaled 3.33 ppm and 0.72 ppm, respectively. In addition, the arithmetic mean of TVOC concentration was 1.77±0.53 ppm inside the examined taxies. In this study, the parameters like measurement time, climate and vehicle conditions were found to have significant effect on the amount of exposure to TVOC.

FIELD SCREENING FOR HALOGENATED VOLATILE ORGANIC COMPOUNDS

Energy Technology Data Exchange (ETDEWEB)

John F. Schabron; Joseph F. Rovani Jr.; Theresa M. Bomstad

2002-06-01

Western Research Institute (WRI) initiated exploratory work towards the development of new field screening methodology and a test kit to measure halogenated volatile organic compounds (VOCs) in the field. Heated diode and corona discharge sensors are commonly used to detect leaks of refrigerants from air conditioners, freezers, and refrigerators. They are both selective to the presence of carbon-halogen bonds. Commercially available heated diode and corona discharge leak detectors were procured and evaluated for halogenated VOC response. The units were modified to provide a digital readout of signal related to VOC concentration. Sensor response was evaluated with carbon tetrachloride and tetrachloroethylene (perchloroethylene, PCE), which represent halogenated VOCs with and without double bonds. The response characteristics were determined for the VOCs directly in headspace in Tedlar bag containers. Quantitation limits in air were estimated. Potential interferences from volatile hydrocarbons, such as toluene and heptane, were evaluated. The effect of humidity was studied also. The performance of the new devices was evaluated in the laboratory by spiking soil samples and monitoring headspace for halogenated VOCs. A draft concept of the steps for a new analytical method was outlined. The results of the first year effort show that both devices show potential utility for future analytical method development work towards the goal of developing a portable test kit for screening halogenated VOCs in the field.

Rapid, facile synthesis of conjugated polymer zwitterions in ionic liquids

Energy Technology Data Exchange (ETDEWEB)

Page, Zachariah A. [Polymer Science & Engineering Department; Conte Center for Polymer Research; University of Massachusetts; Amherst, USA; Liu, Feng [Polymer Science & Engineering Department; Conte Center for Polymer Research; University of Massachusetts; Amherst, USA; Russell, Thomas P. [Polymer Science & Engineering Department; Conte Center for Polymer Research; University of Massachusetts; Amherst, USA; Emrick, Todd [Polymer Science & Engineering Department; Conte Center for Polymer Research; University of Massachusetts; Amherst, USA

2014-01-01

Ionic liquids (ILs) were utilized for the rapid air-stable Suzuki polymerization of polar zwitterionic thiophene monomers, precluding the need for volatile organic solvents, phosphine ligands and phase transfer catalysts typically used in conjugated polymer synthesis.

Nitrate radicals and biogenic volatile organic compounds ...

Science.gov (United States)

Oxidation of biogenic volatile organic compounds (BVOC) by the nitrate radical (NO3) represents one of the important interactions between anthropogenic emissions related to combustion and natural emissions from the biosphere. This interaction has been recognized for more than 3 decades, during which time a large body of research has emerged from laboratory, field, and modeling studies. NO3-BVOC reactions influence air quality, climate and visibility through regional and global budgets for reactive nitrogen (particularly organic nitrates), ozone, and organic aerosol. Despite its long history of research and the significance of this topic in atmospheric chemistry, a number of important uncertainties remain. These include an incomplete understanding of the rates, mechanisms, and organic aerosol yields for NO3-BVOC reactions, lack of constraints on the role of heterogeneous oxidative processes associated with the NO3 radical, the difficulty of characterizing the spatial distributions of BVOC and NO3 within the poorly mixed nocturnal atmosphere, and the challenge of constructing appropriate boundary layer schemes and non-photochemical mechanisms for use in state-of-the-art chemical transport and chemistry–climate models. This review is the result of a workshop of the same title held at the Georgia Institute of Technology in June 2015. The first half of the review summarizes the current literature on NO3-BVOC chemistry, with a particular focus on recent advances in

Potential of select intermediate-volatility organic compounds and consumer products for secondary organic aerosol and ozone formation under relevant urban conditions

Science.gov (United States)

Li, Weihua; Li, Lijie; Chen, Chia-li; Kacarab, Mary; Peng, Weihan; Price, Derek; Xu, Jin; Cocker, David R.

2018-04-01

Emissions of certain low vapor pressure-volatile organic compounds (LVP-VOCs) are considered exempt to volatile organic compounds (VOC) regulations due to their low evaporation rates. However, these compounds may still play a role in ambient secondary organic aerosol (SOA) and ozone formation. The LVP-VOCs selected for this work are categorized as intermediate-volatility organic compounds (IVOCs) according to their vapor pressures and molecular formulas. In this study, the evaporation rates of 14 select IVOCs are investigated with half of them losing more than 95% of their mass in less than one month. Further, SOA and ozone formation are presented from 11 select IVOCs and 5 IVOC-containing generic consumer products under atmospherically relevant conditions using varying radical sources (NOx and/or H2O2) and a surrogate reactive organic gas (ROG) mixture. Benzyl alcohol (0.41), n-heptadecane (0.38), and diethylene glycol monobutyl ether (0.16) are determined to have SOA yields greater than 0.1 in the presence of NOx and a surrogate urban hydrocarbon mixture. IVOCs also influence ozone formation from the surrogate urban mixture by impacting radical levels and NOx availability. The addition of lab created generic consumer products has a weak influence on ozone formation from the surrogate mixture but strongly affects SOA formation. The overall SOA and ozone formation of the generic consumer products could not be explained solely by the results of the pure IVOC experiments.

Characterisation of selected volatile organic compounds in ...

African Journals Online (AJOL)

GCMS), was used to identify volatile compounds at three different temperatures. Fifty volatile compounds, inclusive of 14 acids, 14 alcohols, and 22 esters were identified and quantified in the two brands of indigenous banana beer samples. Only 12 ...

Transformation of organic matter and the emissions of methane and ammonia during storage of liquid manure as affected by acidification

DEFF Research Database (Denmark)

Sommer, Sven G.; Clough, Timothy J.; Balaine, Nimlesh

2017-01-01

), suggesting that DOC may be a predictor for CH4 emission from dilute slurries. volatile fatty acid and total ammoniacal nitrogen concentrations in surface layers were substantially higher than at the center of stored liquid manure, perhaps resulting from microbial activity at the surface. This pattern......Acidification of livestock manure can reduce emission of the greenhouse gases methane (CH4) and nitrous oxide (N2O), as well as ammonia (NH3). We examined the relation between emission of these gases and transformation of organic matter as affected by acidification. Liquid cattle manure......, probably due to the absence of a surface crust. Reductions in NH3 and CH4 emission were highest at the start but declined over time concomitantly with a gradual increase in the stored liquid manure pH. Acidification did not significantly affect CO2 emissions. Emission of CO2 was high, fiveto ten-fold of CH...

Studying volatility from composition, dilution, and heating measurements of secondary organic aerosols formed during α-pinene ozonolysis

Science.gov (United States)

Sato, Kei; Fujitani, Yuji; Inomata, Satoshi; Morino, Yu; Tanabe, Kiyoshi; Ramasamy, Sathiyamurthi; Hikida, Toshihide; Shimono, Akio; Takami, Akinori; Fushimi, Akihiro; Kondo, Yoshinori; Imamura, Takashi; Tanimoto, Hiroshi; Sugata, Seiji

2018-04-01

Traditional yield curve analysis shows that semi-volatile organic compounds are a major component of secondary organic aerosols (SOAs). We investigated the volatility distribution of SOAs from α-pinene ozonolysis using positive electrospray ionization mass analysis and dilution- and heat-induced evaporation measurements. Laboratory chamber experiments were conducted on α-pinene ozonolysis, in the presence and absence of OH scavengers. Among these, we identified not only semi-volatile products, but also less volatile highly oxygenated molecules (HOMs) and dimers. Ozonolysis products were further exposed to OH radicals to check the effects of photochemical aging. HOMs were also formed during OH-initiated photochemical aging. Most HOMs that formed from ozonolysis and photochemical aging had 10 or fewer carbons. SOA particle evaporation after instantaneous dilution was measured at fraction remaining of SOAs decreased with time and the equilibration timescale was determined to be 24-46 min for SOA evaporation. The experimental results of the equilibration timescale can be explained when the mass accommodation coefficient is assumed to be 0.1, suggesting that the existence of low-volatility materials in SOAs, kinetic inhibition, or some combined effect may affect the equilibration timescale measured in this study.

ECOS E-MATRIX Methane and Volatile Organic Carbon (VOC) Emissions Best Practices Database

Energy Technology Data Exchange (ETDEWEB)

Parisien, Lia [The Environmental Council Of The States, Washington, DC (United States)

2016-01-31

This final scientific/technical report on the ECOS e-MATRIX Methane and Volatile Organic Carbon (VOC) Emissions Best Practices Database provides a disclaimer and acknowledgement, table of contents, executive summary, description of project activities, and briefing/technical presentation link.

Liquid metal–organic frameworks

Energy Technology Data Exchange (ETDEWEB)

Gaillac, Romain; Pullumbi, Pluton; Beyer, Kevin A.; Chapman, Karena W.; Keen, David A.; Bennett, Thomas D.; Coudert, François-Xavier

2017-10-09

Metal–organic frameworks (MOFs) are a family of chemically diverse materials, with applications in a wide range of fields, covering engineering, physics, chemistry, biology and medicine. Until recently, research has focused almost entirely on crystalline structures, yet now a clear trend is emerging, shifting the emphasis onto disordered states, including ‘defective by design’ crystals, as well as amorphous phases such as glasses and gels. Here we introduce a strongly associated MOF liquid, obtained by melting a zeolitic imidazolate framework. We combine in situ variable temperature X-ray, ex situ neutron pair distribution function experiments, and first-principles molecular dynamics simulations to study the melting phenomenon and the nature of the liquid obtained. We demonstrate from structural, dynamical, and thermodynamical information that the chemical configuration, coordinative bonding, and porosity of the parent crystalline framework survive upon formation of the MOF liquid.

Liquid metal-organic frameworks

Science.gov (United States)

Gaillac, Romain; Pullumbi, Pluton; Beyer, Kevin A.; Chapman, Karena W.; Keen, David A.; Bennett, Thomas D.; Coudert, François-Xavier

2017-11-01

Metal-organic frameworks (MOFs) are a family of chemically diverse materials, with applications in a wide range of fields, covering engineering, physics, chemistry, biology and medicine. Until recently, research has focused almost entirely on crystalline structures, yet now a clear trend is emerging, shifting the emphasis onto disordered states, including `defective by design’ crystals, as well as amorphous phases such as glasses and gels. Here we introduce a strongly associated MOF liquid, obtained by melting a zeolitic imidazolate framework. We combine in situ variable temperature X-ray, ex situ neutron pair distribution function experiments, and first-principles molecular dynamics simulations to study the melting phenomenon and the nature of the liquid obtained. We demonstrate from structural, dynamical, and thermodynamical information that the chemical configuration, coordinative bonding, and porosity of the parent crystalline framework survive upon formation of the MOF liquid.

Nanoscience with liquid crystals from self-organized nanostructures to applications

CERN Document Server

Li, Quan

2014-01-01

This book focuses on the exciting topic of nanoscience with liquid crystals: from self-organized nanostructures to applications. The elegant self-organized liquid crystalline nanostructures, the synergetic characteristics of liquid crystals and nanoparticles, liquid crystalline nanomaterials, synthesis of nanomaterials using liquid crystals as templates, nanoconfinement and nanoparticles of liquid crystals are covered and discussed, and the prospect of fabricating functional materials is highlighted. Contributions, collecting the scattered literature of the field from leading and active player

Volatile organic compound emissions from Larrea tridentata (creosotebush

Directory of Open Access Journals (Sweden)

A. Guenther

2010-12-01

Full Text Available We present results from the CREosote ATmosphere Interactions through Volatile Emissions (CREATIVE 2009 field study in southern Arizona aimed at quantifying emission rates of VOCs from creosotebush (Larrea tridentata during the summer 2009 monsoon season. This species was chosen because of its vast distribution in North and South American deserts and because its resins have been reported to contain a rich set of volatile organic compounds (VOC. While a variety of ecosystems have been investigated for VOC emissions, deserts remain essentially unstudied, partially because of their low biomass densities and water limitations. However, during the North American monsoon, a pronounced increase in rainfall from an extremely dry June (80 mm occurs over large areas of the Sonoran desert in the southwestern United States and northwestern Mexico. We observed a strong diurnal pattern of branch emissions and ambient concentrations of an extensive suite of VOCs with maxima in early afternoon. These include VOCs typically observed in forest sites (oxygenated VOCs and volatile isoprenoids as well as a large number of other compounds, some of which have not been previously described from any plant including 1-chloro-2-methoxy-benzene and isobutyronitrile. Although generally considered to be derived from anthropogenic sources, we observed emissions of aromatic compounds including benzene, and a broad range of phenolics. Dimethyl sulfide emissions from creosotebush were higher than reported from any previously studied plant suggesting that terrestrial ecosystems should be reconsidered as an important source of this climatically important gas. We also present direct, primary emission measurements of isoprene and its apparent oxidation products methyl vinyl ketone, methacrolein, and 3-methyl furan (the later three compounds are typically assumed to form from secondary reactions within the atmosphere, as well as a group of compounds considered to be fatty acid

Volatile organic compounds released by blowfly larvae and pupae: new perspectives in forensic entomology.

Science.gov (United States)

Frederickx, C; Dekeirsschieter, J; Brostaux, Y; Wathelet, J-P; Verheggen, F J; Haubruge, E

2012-06-10

To evaluate postmortem intervals (PMIs), one should take into account the determined age of necrophagous flies present on the cadaver. However, PMI determination needs further improvement, and rapid and accurate approaches have therefore to be developed. While previous studies have focussed on insect cuticular hydrocarbons, here we explore the volatile profile released by larvae and pupae of Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae). We monitored changes in volatile compounds daily, by headspace solid-phase microextraction, followed by gas chromatography-mass spectrometry. Branched and unbranched hydrocarbons, alcohols, esters and acids were identified, and the volatile profile was shown to vary, in both composition and quantity, with the age of the larva/pupa under investigation. We concluded, based on the analysis of the released volatile organic compounds, that it is possible to increase the accuracy of the estimated PMI, through improved estimation of the age of blowflies present on the cadaver. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Treatment of radioactive organics liquid wastes

International Nuclear Information System (INIS)

Morales Galarce, Tania

1999-01-01

Because of the danger that radioactive wastes can pose to society and to the environment a viable treatment alternative must be developed to prepare these wastes for final disposal. The waste studied in this work is a liquid organic waste contaminated with the radioisotope tritium. This must be treated and then changed into solid form in a 200 liter container. This study defined an optimum formulation that immobilizes the liquid waste. The organic waste is first submitted to an absorption treatment, with Celite absorbent, which had the best physical characteristics from the point of view of radioactive waste management. Then this was solidified by forming a cement mortar, using a highly resistant local cement, Polpaico 400. Various mixes were tested, with different water/cement, waste/absorbent and absorbed waste/cement ratios, until a mixture that met the quality control requirements was achieved. The optimum mixture obtained has a water/cement ratio of 0.35 (p/p) that is the amount of water needed to make the mixture workable, and minimum water for hydrating the cement; a waste/absorbent ration of 0.5 (v/v), where the organic liquid is totally absorbed, and is incorporated in the solid's crystalline network; and an absorbed waste/cement ratio of 0.8 (p/p), which represents the minimum amount of cement needed to obtain a solid product with the required mechanical resistance. The mixture's components join together with no problem, to produce a good workable mixture. It takes about 10 hours for the mixture to harden. After 14 days, the resulting solid product has a resistance to compression of 52 Kgf/cm2. The formulation contains 22.9% immobilized organic waste, 46.5% cement, 14.3% Celite and 16.3% water. Organic liquid waste can be treated and a solid product obtained, that meets the qualitative and quantitative parameters required for its disposal. (CW)

Stability of volatile organics in environmental soil samples

Energy Technology Data Exchange (ETDEWEB)

Maskarinec, M.P.; Bayne, C.K.; Jenkins, R.A.; Johnson, L.H.; Holladay, S.K.

1992-11-01

This report focuses on data generated for the purpose of establishing the stability of 19 volatile organic compounds in environmental soil samples. The study was carried out over a 56 day (for two soils) and a 111 day (for one reference soil) time frame and took into account as many variables as possible within the constraints of budget and time. The objectives of the study were: 1) to provide a data base which could be used to provide guidance on pre-analytical holding times for regulatory purposes; and 2) to provide a basis for the evaluation of data which is generated outside of the currently allowable holding times.

Combustible ionic liquids by design: is laboratory safety another ionic liquid myth?

Science.gov (United States)

Smiglak, Marcin; Reichert, W Mathew; Holbrey, John D; Wilkes, John S; Sun, Luyi; Thrasher, Joseph S; Kirichenko, Kostyantyn; Singh, Shailendra; Katritzky, Alan R; Rogers, Robin D

2006-06-28

The non-flammability of ionic liquids (ILs) is often highlighted as a safety advantage of ILs over volatile organic compounds (VOCs), but the fact that many ILs are not flammable themselves does not mean that they are safe to use near fire and/or heat sources; a large group of ILs (including commercially available ILs) are combustible due to the nature of their positive heats of formation, oxygen content, and decomposition products.

Nonuniformities in organic liquid ionization calorimeters

International Nuclear Information System (INIS)

Wenzel, W.A.

1989-06-01

Hermeticity and uniformity in SSC calorimeter designs are compromised by structure and modularity. Some of the consequences of the cryogenic needs of liquid argon calorimetry are relatively well known. If the active medium is an organic liquid (TMP, TMS, etc.), a large number of independent liquid volumes is needed for safety and for rapid liquid exchange to eliminate local contamination. Modular construction ordinarily simplifies fabrication, assembly, handling and preliminary testing at the price of additional walls, other dead regions and many nonuniformities. Here we examine ways of minimizing the impact of some generic nonuniformities on the quality of calorimeter performance. 6 refs., 7 figs

Supercritical fluids in ionic liquids

NARCIS (Netherlands)

Kroon, M.C.; Peters, C.J.; Plechkova, N.V.; Seddon, K.R.

2014-01-01

Ionic liquids and supercritical fluids are both alternative environmentally benign solvents, but their properties are very different. Ionic liquids are non-volatile but often considered highly polar compounds, whereas supercritical fluids are non-polar but highly volatile compounds. The combination

Analysis of Organic Volatile Flavor Compounds in Fermented Stinky Tofu Using SPME with Different Fiber Coatings

Directory of Open Access Journals (Sweden)

Wei Guan

2012-03-01

Full Text Available The organic volatile flavor compounds in fermented stinky tofu (FST were studied using SPME-GC/MS. A total of 39 volatile compounds were identified, including nine esters, seven alcohols, five alkenes, four sulfides, three heterocycles, three carboxylic acids, three ketones, two aldehydes, one phenol, one amine and one ether. These compounds were determined by MS, and conformed by comparison of the retention times of the separated constituents with those of authentic samples and by comparison of retention indexes (RIs of separated constituents with the RIs reported in the literature. The predominant volatile compound in FST was indole, followed by dimethyl trisulfide, phenol, dimethyl disulfide and dimethyl tetrasulfide. In order to find a better extraction time, the extraction times was optimized for each type of SPME fiber; the results show that the best extraction time for Carboxen/PDMS is 60 min, for PDMS/DVB 30 min, for DVB/CAR/PDMS 60 min and for PDMS 75 min. Of the four fibers used in this work, Carboxen/PDMS is found to be the most suitable to extract the organic volatile flavor compounds in fermented stinky tofu.

Holographic detection of hydrocarbon gases and other volatile organic compounds.

Science.gov (United States)

Martínez-Hurtado, J L; Davidson, C A B; Blyth, J; Lowe, C R

2010-10-05

There is a need to develop sensors for real-time monitoring of volatile organic compounds (VOCs) and hydrocarbon gases in both external and indoor environments, since these compounds are of growing concern in human health and welfare. Current measurement technology for VOCs requires sophisticated equipment and lacks the prospect for rapid real-time monitoring. Holographic sensors can give a direct reading of the analyte concentration as a color change. We report a technique for recording holographic sensors by laser ablation of silver particles formed in situ by diffusion. This technique allows a readily available hydrophobic silicone elastomer to be transformed into an effective sensor for hydrocarbon gases and other volatile compounds. The intermolecular interactions present between the polymer and molecules are used to predict the sensor performance. The hydrophobicity of this material allows the sensor to operate without interference from water and other atmospheric gases and thus makes the sensor suitable for biomedical, industrial, or environmental analysis.

Volatile organic monitor for industrial effluents

International Nuclear Information System (INIS)

Laguna, G.R.; Peter, F.J.; Stuart, A.D.; Loyola, V.M.

1993-07-01

1990 amendments to the Clean Air Act have created the need for instruments capable of monitoring volatile organic compounds (VOCS) in public air space in an unattended and low cost manner. The purpose of the study was to develop and demonstrate the capability to do long term automatic and unattended ambient air monitoring using an inexpensive portable analytic system at a commercial manufacturing plant site. A gas chromatograph system personal computer hardware, meteorology tower ampersand instruments, and custom designed hardware and software were developed. Comparison with an EPA approved method was performed. The system was sited at an aircraft engines manufacturing site and operated in a completely unattended mode for 60 days. Two VOCs were monitored every 30 minutes during the 24hr day. Large variation in the concentration from 800ppb to the limits of detection of about 10ppb were observed. Work to increase the capabilities of the system is ongoing

Liquid Organic Fertilizers for Sustainable Agriculture: Nutrient Uptake of Organic versus Mineral Fertilizers in Citrus Trees.

Science.gov (United States)

Martínez-Alcántara, Belén; Martínez-Cuenca, Mary-Rus; Bermejo, Almudena; Legaz, Francisco; Quiñones, Ana

2016-01-01

The main objective of this study was to compare the performance of two liquid organic fertilizers, an animal and a plant-based fertilizer, with mineral fertilization on citrus trees. The source of the fertilizer (mineral or organic) had significant effect in the nutritional status of the organic and conventionally managed mandarins. Nutrient uptake, vegetative growth, carbohydrate synthesis and soil characteristics were analyzed. Results showed that plants fertilized with animal based liquid fertilizers exhibited higher total biomass with a more profuse development of new developing organs (leaves and fibrous roots). Liquid organic fertilization resulted in an increased uptake of macro and micronutrients compared to mineral fertilized trees. Moreover, organic fertilization positively affected the carbohydrate content (fructose, glucose and sucrose) mainly in summer flush leaves. Liquid organic fertilization also resulted in an increase of soil organic matter content. Animal-based fertilizer, due to intrinsic composition, increased total tree biomass and carbohydrate leaves content, and led to lower soil nitrate concentration and higher P and Mg exchangeable in soil extract compared to vegetal-based fertilizer. Therefore, liquid organic fertilizers could be used as an alternative to traditional mineral fertilization in drip irrigated citrus trees.

Impact of elevated CO2 and O3 concentrations on biogenic volatile organic compounds emissions from Ginkgo biloba.

Science.gov (United States)

Li, Dewen; Chen, Ying; Shi, Yi; He, Xingyuan; Chen, Xin

2009-04-01

In natural environment with ambient air, ginkgo trees emitted volatile organic compounds 0.18 microg g(-1) h(-1) in July, and 0.92 microg g(-1) h(-1) in September. Isoprene and limonene were the most abundant detected compounds. In September, alpha-pinene accounted for 22.5% of the total. Elevated CO(2) concentration in OTCs increased isoprene emission significantly in July (pemission was enhanced in July and decreased in September by elevated CO(2). Exposed to elevated O(3) increased the isoprene and monoterpenes emissions in July and September, and the total volatile organic compounds emission rates were 0.48 microg g(-1) h(-1) (in July) and 2.24 microg g(-1) h(-1) (in September), respectively. The combination of elevated CO(2) and O(3) did not have any effect on biogenic volatile organic compounds emissions, except increases of isoprene and Delta3-carene in September.

Biological relevance of volatile organic compounds emitted during the pathogenic interactions between apple plants and Erwinia amylovora.

Science.gov (United States)

Cellini, Antonio; Buriani, Giampaolo; Rocchi, Lorenzo; Rondelli, Elena; Savioli, Stefano; Rodriguez Estrada, Maria T; Cristescu, Simona M; Costa, Guglielmo; Spinelli, Francesco

2018-01-01

Volatile organic compounds emitted during the infection of apple (Malus pumila var. domestica) plants by Erwinia amylovora or Pseudomonas syringae pv. syringae were studied by gas chromatography-mass spectrometry and proton transfer reaction-mass spectrometry, and used to treat uninfected plants. Infected plants showed a disease-specific emission of volatile organic compounds, including several bio-active compounds, such as hexenal isomers and 2,3-butanediol. Leaf growth promotion and a higher resistance to the pathogen, expressed as a lower bacterial growth and migration in plant tissues, were detected in plants exposed to volatile compounds from E. amylovora-infected plants. Transcriptional analysis revealed the activation of salicylic acid synthesis and signal transduction in healthy plants exposed to volatiles produced by E. amylovora-infected neighbour plants. In contrast, in the same plants, salicylic acid-dependent responses were repressed after infection, whereas oxylipin metabolism was activated. These results clarify some metabolic and ecological aspects of the pathogenic adaptation of E. amylovora to its host. © 2016 BSPP AND JOHN WILEY & SONS LTD.

75 FR 57390 - Approval and Promulgation of Implementation Plans; Alabama: Volatile Organic Compounds

Science.gov (United States)

2010-09-21

... Environmental Management (ADEM) on March 3, 2010. The revision modifies the definition of ``volatile organic... the VOC definition on the basis that these compounds make a negligible contribution to tropospheric..., 2009, which excludes these compounds from the regulatory VOC definition. This action is being taken...

"Liquid-liquid-solid"-type superoleophobic surfaces to pattern polymeric semiconductors towards high-quality organic field-effect transistors.

Science.gov (United States)

Wu, Yuchen; Su, Bin; Jiang, Lei; Heeger, Alan J

2013-12-03

Precisely aligned organic-liquid-soluble semiconductor microwire arrays have been fabricated by "liquid-liquid-solid" type superoleophobic surfaces directed fluid drying. Aligned organic 1D micro-architectures can be built as high-quality organic field-effect transistors with high mobilities of >10 cm(2) ·V(-1) ·s(-1) and current on/off ratio of more than 10(6) . All these studies will boost the development of 1D microstructures of organic semiconductor materials for potential application in organic electronics. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Improved exposure estimation in soil screening and cleanup criteria for volatile organic chemicals.

Science.gov (United States)

DeVaull, George E

2017-09-01

Soil cleanup criteria define acceptable concentrations of organic chemical constituents for exposed humans. These criteria sum the estimated soil exposure over multiple pathways. Assumptions for ingestion, dermal contact, and dust exposure generally presume a chemical persists in surface soils at a constant concentration level for the entire exposure duration. For volatile chemicals, this is an unrealistic assumption. A calculation method is presented for surficial soil criteria that include volatile depletion of chemical for these uptake pathways. The depletion estimates compare favorably with measured concentration profiles and with field measurements of soil concentration. Corresponding volatilization estimates compare favorably with measured data for a wide range of volatile and semivolatile chemicals, including instances with and without the presence of a mixed-chemical residual phase. Selected examples show application of the revised factors in estimating screening levels for benzene in surficial soils. Integr Environ Assess Manag 2017;13:861-869. © 2017 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC). © 2017 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Comparison of the neurotoxicities between volatile organic compounds and fragrant organic compounds on human neuroblastoma SK-N-SH cells and primary cultured rat neurons

Directory of Open Access Journals (Sweden)

Yasue Yamada

2015-01-01

Full Text Available These are many volatile organic compounds (VOCs that are synthesized, produced from petroleum or derived from natural compounds, mostly plants. Fragrant and volatile organic compounds from plants have been used as food additives, medicines and aromatherapy. Several clinical and pathological studies have shown that chronic abuse of VOCs, mainly toluene, causes several neuropsychiatric disorders. Little is known about the mechanisms of neurotoxicity of the solvents. n-Octanal, nonanal, and 2-ethyl-1-hexanol, which are used catalyzers or intermediates of chemical reactions, are released into the environment. Essential oils have the functions of self-defense, sterilization, and antibiosis in plants. When volatile organic compounds enter the body, there is the possibility that they will pass through the blood–brain barrier (BBB and affect the central nervous system (CNS. However, the direct effects of volatile organic compounds on neural function and their toxicities are still unclear. We compared the toxicities of n-octanal, nonanal and 2-ethyl-1-hexanol with those of five naturally derived fragrant organic compounds (FOCs, linalool, cis-3-hexen-1-ol, isoamyl alcohol, n-propyl alcohol and n-phenethyl alcohol. MTT assay of human neuroblastoma SK-N-SH cells showed that the IC50 values of linalool, cis-3-hexen-1-ol, isoamyl alcohol, n-propyl alcohol and phenethyl alcohol were 1.33, 2.3, >5, >5, and 2.39 mM, respectively, and the IC50 values of toluene, n-octanal, nonanal and 2-ethyl-1-hexanol were 850, 37.2, 8.31 and 15.1 μM, respectively. FOCs showed lower toxicities than those of VOCs. These results indicate that FOCs are safer than other compounds.

Organic contamination of ground water at Gas Works Park, Seattle, Washington

International Nuclear Information System (INIS)

Turney, G.L.; Goerlitz, D.F.

1990-01-01

Gas Works Park, in Seattle, Washington, is located on the site of a coal and oil gasification plant that ceased operation in 1956. During operation, many types of wastes, including coal, tar, and oil, accumulated on-site. The park soil is currently (1986) contaminated with compounds such as polynuclear aromatic hydrocarbons, volatile organic compounds, trace metals, and cyanide. Analyses of water samples from a network of observation wells in the park indicate that these compounds are also present in the ground water. Polynuclear aromatic hydrocarbons and volatile organic compounds were identified in ground water samples in concentrations as large as 200 mg/L. Concentrations of organic compounds were largest where ground water was in contact with a non-aqueous phase liquid in the soil. Where no non-aqueous phase liquid was present, concentrations were much smaller, even if the ground water was in contact with contaminated soils. This condition is attributed to weathering processes in which soluble, low-molecular-weight organic compounds are preferentially dissolved from the non-aqueous phase liquid into the ground water. Where no non-aqueous phase liquid is present, only stained soils containing relatively insoluble, high-molecular-weight compounds remain. Concentrations of organic contaminants in the soils may still remain large

Organic contamination of ground water at Gas Works Park, Seattle, Washington

Science.gov (United States)

Turney, G.L.; Goerlitz, D.F.

1990-01-01

Gas Works Park, in Seattle, Washington, is located on the site of a coal and oil gasification plant that ceased operation in 1956. During operation, many types of wastes, including coal, tar, and oil, accumulated on-site. The park soil is currently (1986) contaminated with compounds such as polynuclear aromatic hydrocarbons, volatile organic compounds, trace metals, and cyanide. Analyses of water samples from a network of observation wells in the park indicate that these compounds are also present in the ground water. Polynuclear aromatic hydrocarbons and volatile organic compounds were identified in ground water samples in concentrations as large as 200 mg/L. Concentrations of organic compounds were largest where ground water was in contact with a non-aqueous phase liquid in the soil. Where no non-aqueous phase liquid was present, concentrations were much smaller, even if the ground water was in contact with contaminated soils. This condition is attributed to weathering processes in which soluble, low-molecular-weight organic compounds are preferentially dissolved from the non-aqueous phase liquid into the ground water. Where no non-aqueous phase liquid is present, only stained soils containing relatively insoluble, high-molecular-weight compounds remain. Concentrations of organic contaminants in the soils may still remain large.

Research on release rate of volatile organic compounds in typical vessel cabin

Directory of Open Access Journals (Sweden)

ZHANG Jinlan

2018-02-01

Full Text Available [Objectives] Volatile Organic Compounds (VOC should be efficiently controlled in vessel cabins to ensure the crew's health and navigation safety. As an important parameter, research on release rate of VOCs in cabins is required. [Methods] This paper develops a method to investigate this parameter of a ship's cabin based on methods used in other closed indoor environments. A typical vessel cabin is sampled with Tenax TA tubes and analyzed by Automated Thermal Desorption-Gas Chromatography-Mass Spectrometry (ATD-GC/MS. The lumped mode is used and the release rate of Benzene, Toluene, Ethylbenzene and Xylene (BTEX, the typical representatives of VOCs, is obtained both in closed and ventilated conditions. [Results] The results show that the content of xylene and Total Volatile Organic Compounds (TVOC exceed the indoor environment standards in ventilated conditions. The BTEX release rate is similar in both conditions except for the benzene. [Conclusions] This research builds a method to measure the release rate of VOCs, providing references for pollution character evaluation and ventilation and purification system design.

Photodecomposition of volatile organic compounds using TiO2 nanoparticles.

Science.gov (United States)

Jwo, Ching-Song; Chang, Ho; Kao, Mu-Jnug; Lin, Chi-Hsiang

2007-06-01

This study examined the photodecomposition of volatile organic compounds (VOCs) using TiO2 catalyst fabricated by the Submerged Arc Nanoparticle Synthesis System (SANSS). TiO2 catalyst was employed to decompose volatile organic compounds and compare with Degussa-P25 TiO2 in terms of decomposition efficiency. In the electric discharge manufacturing process, a Ti bar, applied as the electrode, was melted and vaporized under high temperature. The vaporized Ti powders were then rapidly quenched under low-temperature and low-pressure conditions in deionized water, thus nucleating and forming nanocrystalline powders uniformly dispersed in the base solvent. The average diameter of the TiO2 nanoparticles was 20 nm. X-ray diffraction analysis confirmed that the nanoparticles in the deionized water were Anatase type TiO2. It was found that gaseous toluene exposed to UV irradiation produced intermediates that were even harder to decompose. After 60-min photocomposition, Degussa-P25 TiO2 reduced the concentration of gaseous toluene to 8.18% while the concentration after decomposition by SANSS TiO2 catalyst dropped to 0.35%. Under UV irradiation at 253.7 +/- 184.9 nm, TiO2 prepared by SANSS can produce strong chemical debonding energy, thus showing great efficiency, superior to that of Degussa-P25 TiO2, in decomposing gaseous toluene and its intermediates.

(Semi)volatile organic compounds and microbiological entities in snow during OASIS Barrow 2009

Science.gov (United States)

Ariya, P.; Kos, G.

2009-12-01

Gregor Kos (1), Nafissa Adechina (2), Dwayne Lutchmann (2) , Roya Mortazavi, and Parisa Ariya* (1), (2) (1) McGill University, Department of Atmospheric and Oceanic Sciences, 805 Sherbrooke Street West, Montreal, Quebec, H3A 2K6, Canada (2) McGill University, Department of Chemistry, 801 Sherbrooke Street West, Montreal, Quebec, H3A 2K6, Canada an active medium for the deposition of (semi-)volatile (bio)organic compounds. We collected surface snow samples during the OASIS Barrow campaign in March 2009 for analysis of semi-volatile organic compounds using solid phase microextraction and gas chromatography with mass spectrometric detection (SPME-GC/MS). Additioal gab samples were taken for analysis of non-methane hydrocarbons in air. More over, we analyzed for microbial species in air and snow. Identifed organic compounds covered a wide range of functionalities andmolecular weigts, including oxygenated reactive speces such as aldehydes (e.g., hexanal to decanal), alcohols (e.g., hexanol, octanol) and aromatic species (e.g., methyl- and ethylbenzenes). Quantification data for selected aromatic species are presented with concentrations in the upper ng/L range. We will present our preliminary data on microbiological species, and will discuss the potential mplications of the results for organic snow chemistry.

Use of liquid scintillation counting for quantitative analysis of volatile organic compounds in batch isotherm analysis

International Nuclear Information System (INIS)

Wickman, D.C.

1987-01-01

An estimate of how rapidly hazardous wastes move through subsurface soils via ground water is important to predict the location and concentration of the contaminant plume vs. time. The contaminated ground water system may be viewed as an HPLC column with the organic components of the waste in adsorption/desorption equilibrium with the subsurface soil. The batch isotherm method was chosen to determine the equilibrium constant between trichloroethylene, o-dichlorobenzene, 1-methyl naphthalene and aquifer materials obtained from various locations around the country. Liquid Scintillation counting has been found to be an excellent technique for batch isotherm analysis; using 14C labeled compounds, it affords unattended analysis, accuracy at very low concentrations and rapid data reduction. Ten ml serum containing about 5 ml water and a known weight of soil (approximately 2 grams) were spiked with the labeled solution to yield organic solute concentrations in the range of 0.02-1.0 mg/1. Six different concentrations were used. After spiking, the bottles were filled to the top with water and crimp sealed with teflon coated septa. All soil containing bottles were then rotated at 50 rpm and 22 degrees Celsius. Twenty-four hours later the bottles were uncapped and a 1.4 ml aliquot was removed and placed in scintillation cocktail and counted

Car indoor air pollution by volatile organic compounds and aldehydes in Japan

Directory of Open Access Journals (Sweden)

Kouichi Tatsu

2016-06-01

Full Text Available Fifty-five organic substances including volatile organic compounds (VOCs and aldehydes present in indoor air were measured from 24 car cabins in Japan. A screening-level risk assessment was also performed. Acetaldehyde (3.81–36.0 μg/m3, formaldehyde (3.26–26.7 μg/m3, n-tetradecane (below the method quantification limit (organic compounds originated from the car interior materials. Total volatile organic compound (TVOC concentrations in 14 car cabins (58% of all car cabins exceeded the advisable values established by the Ministry of Health, Labour and Welfare of Japan (400 μg/m3. The highest TVOC concentration (1136 μg/m3 was found in a new car (only one month since its purchase date. Nevertheless, TVOC concentrations exceeded the advisable value even for cars purchased over 10 years ago. Hazard quotients (HQs for formaldehyde obtained using measured median and highest concentrations in both exposure scenarios for occupational use (residential time in a car cabin was assumed to be 8 h were higher than that expected, a threshold indicative of potential adverse effects. Under the same exposure scenarios, HQ values for all other organic compounds remained below this threshold.

Determination of Organic Pollutants in Small Samples of Groundwaters by Liquid-Liquid Extraction and Capillary Gas Chromatography

DEFF Research Database (Denmark)

Harrison, I.; Leader, R.U.; Higgo, J.J.W.

1994-01-01

A method is presented for the determination of 22 organic compounds in polluted groundwaters. The method includes liquid-liquid extraction of the base/neutral organics from small, alkaline groundwater samples, followed by derivatisation and liquid-liquid extraction of phenolic compounds after neu...... neutralisation. The extracts were analysed by capillary gas chromatography. Dual detection by flame Ionisation and electron capture was used to reduce analysis time....

Managing and Harnessing Volatile Oil Windfalls

NARCIS (Netherlands)

van den Bremer, T.S.; van der Ploeg, F.

2013-01-01

Three funds are necessary to manage an oil windfall: intergenerational, liquidity, and investment funds. The optimal liquidity fund is bigger if the windfall lasts longer and oil price volatility, prudence, and the GDP share of oil rents are high and productivity growth is low. The paper applies the

Emission of Biogenic Volatile Organic Compounds in the Arctic

DEFF Research Database (Denmark)

Lindwall, Frida

, emitted in order to communicate within and between trophic levels and as protection against biotic and abiotic stresses, or as byproducts. Some BVOCs are very reactive, and when entering the atmosphere they rapidly react with for example hydroxyl radicals and ozone, affecting the oxidative capacity......Emissions of biogenic volatile organic compounds (BVOCs) from arctic ecosystems are scarcely studied and the effect of climate change on BVOC emissions even less so. BVOCs are emitted from all living organisms and play a role for atmospheric chemistry. The major part of BVOCs derives from plants...... in the atmosphere. This may warm the climate due to a prolonged lifetime of the potent greenhouse gas methane in the atmosphere. However, oxidized BVOCs may participate in formation or growth of aerosols, which in turn may mitigate climate warming. Climate change in the Arctic, an area characterized by short...

Polish and Silesian Non-Profit Organizations Liquidity Strategies

OpenAIRE

Michalski, Grzegorz; Mercik, Aleksander

2013-01-01

The kind of realized mission inflows the sensitivity to risk. Among other factors, the risk results from decision about liquid assets investment level and liquid assets financing. The higher the risk exposure, the higher the level of liquid assets. If the specific risk exposure is smaller, the more aggressive could be the net liquid assets strategy. The organization choosing between various solutions in liquid assets needs to decide what level of risk is acceptable for her owners (or donors) ...

Determination of tetrachloroethylene and other volatile halogenated organic compounds in oil wastes by headspace SPME GC-MS

Energy Technology Data Exchange (ETDEWEB)

Fabbri, D.; Bezzi, R.; Torri, C.; Galletti, P.; Tagliavini, E. [Bologna Univ., Ravenna (Italy). Lab. of Chemistry, C.I.R.S.A

2007-09-15

Oil wastes and slops are complex mixtures of hydrocarbons, which may contain a variety of contaminants including tetrachloroethylene (perchloroethylene, PCE) and other volatile halogenated organic compounds (VHOCs). The analytical determination of PCE at trace levels in petroleum-derived matrices is difficult to carry out in the presence of large amounts of hydrocarbon matrix components. In the following study, we demonstrate that headspace solid-phase microextraction (HS-SPME) combined with GC-MS analysis can be applied for the rapid measurement of PCE concentration in oil samples. The HS-SPME method was developed using liquid paraffin as matrix matching reference material for external and internal calibration and optimisation of experimental parameters. The limit of quantitation was 0.05 mg kg{sup -1}, and linearity was established up to 25 mg kg{sup -1}. The HS-SPME method was extended to several VHOCs, including trichloroethylene (TCE) in different matrices and was applied to the quantitative analysis of PCE and TCE in real samples.

User's guide for polyethylene-based passive diffusion bag samplers to obtain volatile organic compound concentrations in wells. Part I, Deployment, recovery, data interpretation, and quality control and assurance

Science.gov (United States)

Vroblesky, Don A.

2001-01-01

Diffusion samplers installed in observation wells were found to be capable of yielding representative water samples for chlorinated volatile organic compounds. The samplers consisted of polyethylene bags containing deionized water and relied on diffusion of chlorinated volatile organic compounds through the polyethylene membrane. The known ability of polyethylene to transmit other volatile compounds, such as benzene and toluene, indicates that the samplers can be used for a variety of volatile organic compounds. In wells at the study area, the volatile organic compound concentrations in water samples obtained using the samplers without prior purging were similar to concentrations in water samples obtained from the respective wells using traditional purging and sampling approaches. The low cost associated with this approach makes it a viable option for monitoring large observation-well networks for volatile organic compounds.

Qualitative and Quantitative Analysis of Volatile Components of Zhengtian Pills Using Gas Chromatography Mass Spectrometry and Ultra-High Performance Liquid Chromatography.

Science.gov (United States)

Liu, Cui-Ting; Zhang, Min; Yan, Ping; Liu, Hai-Chan; Liu, Xing-Yun; Zhan, Ruo-Ting

2016-01-01

Zhengtian pills (ZTPs) are traditional Chinese medicine (TCM) which have been commonly used to treat headaches. Volatile components of ZTPs extracted by ethyl acetate with an ultrasonic method were analyzed by gas chromatography mass spectrometry (GC-MS). Twenty-two components were identified, accounting for 78.884% of the total components of volatile oil. The three main volatile components including protocatechuic acid, ferulic acid, and ligustilide were simultaneously determined using ultra-high performance liquid chromatography coupled with diode array detection (UHPLC-DAD). Baseline separation was achieved on an XB-C18 column with linear gradient elution of methanol-0.2% acetic acid aqueous solution. The UHPLC-DAD method provided good linearity (R (2) ≥ 0.9992), precision (RSD components, protocatechuic acid, ferulic acid, and ligustilide, in 13 batches of ZTPs, which is suitable for discrimination and quality assessment of ZTPs.

A numerical solution to three-dimensional multiphase transport of volatile organic compounds in unsaturated soils -- with an application to the remedial method of in-situ volatilization

International Nuclear Information System (INIS)

Filley, T.; Tomasko, D.

1992-04-01

Part I of this paper presents the development and application of a numerical model for determining the fate and transport of volatile organic compounds (VOCS) in the unsaturated zone resulting from forced volatilization and gaseous advection-dispersion of organic vapor in a multipartitioned three-dimensional environment. The model allows for single-component transport in the gas and water phases. The hydrocarbon is assumed to be in specific retention and, therefore, immobile. Partitioning of the hydrocarbon between the oil, water, gas, and soil is developed as rate-limited functions that are incorporated into sink/source terms in the transport equations. The code for the model was developed specifically to investigate in-situ volatilization (ISV) remedial strategies, predict the extent of cleanup from information obtained at a limited number of measurement locations, and to help design ISV remedial systems. Application of the model is demonstrated for a hypothetical one-dimensional ISV system. Part II of this paper will present the analysis of an existing ISV system using the full three-dimensional capability of the model

Evaluation of the volatility basis-set approach for the simulation of organic aerosol formation in the Mexico City metropolitan area

Directory of Open Access Journals (Sweden)

A. P. Tsimpidi

2010-01-01

Full Text Available New primary and secondary organic aerosol modules have been added to PMCAMx, a three dimensional chemical transport model (CTM, for use with the SAPRC99 chemistry mechanism based on recent smog chamber studies. The new modelling framework is based on the volatility basis-set approach: both primary and secondary organic components are assumed to be semivolatile and photochemically reactive and are distributed in logarithmically spaced volatility bins. This new framework with the use of the new volatility basis parameters for low-NO_x and high-NO_x conditions tends to predict 4–6 times higher anthropogenic SOA concentrations than those predicted with the older generation of models. The resulting PMCAMx-2008 was applied in Mexico City Metropolitan Area (MCMA for approximately a week during April 2003 during a period of very low regional biomass burning impact. The emission inventory, which uses as a starting point the MCMA 2004 official inventory, is modified and the primary organic aerosol (POA emissions are distributed by volatility based on dilution experiments. The predicted organic aerosol (OA concentrations peak in the center of Mexico City, reaching values above 40 μg m⁻³. The model predictions are compared with the results of the Positive Matrix Factorization (PMF analysis of the Aerosol Mass Spectrometry (AMS observations. The model reproduces both Hydrocarbon-like Organic Aerosol (HOA and Oxygenated Organic Aerosol (OOA concentrations and diurnal profiles. The small OA underprediction during the rush-hour periods and overprediction in the afternoon suggest potential improvements to the description of fresh primary organic emissions and the formation of the oxygenated organic aerosols, respectively, although they may also be due to errors in the simulation of dispersion and vertical mixing. However, the AMS OOA data are not specific enough to prove that the model reproduces the organic aerosol

Pre-digestion to enhance volatile fatty acids (VFAs) concentration as a carbon source for denitrification in treatment of liquid swine manure.

Science.gov (United States)

Wu, Sarah Xiao; Chen, Lide; Zhu, Jun; Walquist, McKenzie; Christian, David

2018-04-30

Insufficient denitrification in biological treatment is often a result of the lack of a carbon source. In this study, use of the volatile fatty acids (VFAs) generated via pre-digestion as a carbon source to improve denitrification in sequencing batch reactor (SBR) treatment of liquid swine manure was investigated. The pre-digestion of swine manure was realized by storing the manure in a sealed container in room temperature and samples were taken periodically from the container to determine the VFA levels. The results showed that after 14 days of pre-digestion, the VFA level in the digested liquid was increased by 200%. A polynomial relationship for the VFA level in the digested manure with the digestion time was observed with a correlation coefficient being 0.9748. Two identical SBRs were built and operated on 8-h cycles in parallel, with one fed with pre-digested and the other raw swine manure. There were five phases included in each cycle, i.e., anaerobic (90 min), anoxic (150 min), anoxic/anaerobic (90 min), anoxic/aerobic (120 min), and settle/decant (30 min), and the feeding was split to 600 mL/200 mL and performed at the beginning of and 240 min into the cycle. The SBR fed on pre-digested swine manure achieved successful denitrification with only 0.35 mg/L nitrate left in the effluent, compared to 15.9 mg/L found in the effluent of the other SBR. Nitrite was not detected in the effluent from both SBRs. The results also indicated that there was no negative impact of feeding SBRs with the pre-digested liquid swine manure for treatment on the removal of other constituents such as total solids (TS), volatile solids (VS), suspended solids (SS), volatile suspended solids (VSS), and soluble chemical oxygen demand (COD). Therefore, anaerobic digestion as a pretreatment can be an effective way to condition liquid swine manure for SBR treatment to achieve sufficient nitrate removal.

Head Space Solid Phase Micro-Extraction (HS - SPME of volatile organic compounds produced by Sporidiobolus salmonicolor (CBS 2636

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Eunice Valduga

2010-12-01

Full Text Available The aim of the present study was the assessment of volatile organic compounds produced by Sporidiobolus salmonicolor (CBS 2636 using methyl and ethyl ricinoleate, ricinoleic acid and castor oil as precursors. The analysis of the volatile organic compounds was carried out using Head Space Solid Phase Micro-Extraction (HS - SPME. Factorial experimental design was used for investigating extraction conditions, verifying stirring rate (0-400 rpm, temperature (25-60 ºC, extraction time (10-30 minutes, and sample volume (2-3 mL. The identification of volatile organic compounds was carried out by Gas Chromatography with Mass Spectrum Detector (GC/MSD. The conditions that resulted in maximum extraction were: 60 ºC, 10 minutes extraction, no stirring, sample volume of 2.0 mL, and addition of saturated KCl (1:10 v/v. In the bio-production of volatile organic compounds the effect of stirring rate (120-200 rpm, temperature (23-33 ºC, pH (4.0-8.0, precursor concentration (0.02-0.1%, mannitol (0-6%, and asparagine concentration (0-0.2% was investigated. The bio-production at 28 ºC, 160 rpm, pH 6,0 and with the addition of 0.02% ricinoleic acid to the medium yielded the highest production of VOCs, identified as 1,4-butanediol, 1,2,2-trimethylciclopropilamine, beta-ionone; 2,3-butanodione, pentanal, tetradecane, 2-isononenal, 4-octen-3-one, propanoic acid, and octadecane.

SOLUTION THERMODYNAMICS OF TRICLOSAN AND TRICLOCARBAN IN SOME VOLATILE ORGANIC SOLVENTS

OpenAIRE

DELGADO, Daniel R.; R. HOLGUIN, Andres; MARTÍNEZ, Fleming

2012-01-01

Thermodynamic functions of Gibbs energy, enthalpy, and entropy for the solution processes of the antimicrobial drugs Triclosan and Triclocarban in five volatile organic solvents were calculated from solubility values at temperatures from 293.15 to 313.15 K. Triclosan and Triclocarban solubility was determined in acetone, acetonitrile (AcCN), ethyl acetate (AcOEt), methanol (MetOH), and cyclohexane (CH). The excess of Gibbs energy and the activity coefficients of the solutes were also calculat...

Infinite dilution activity coefficients of volatile organic compounds in two ionic liquids composed of the tris(pentafluoroethyl)trifluorophosphate ([FAP]) anion and a functionalized cation

International Nuclear Information System (INIS)

Órfão, Eliana Fernandes; Dohnal, Vladimír; Blahut, Aleš

2013-01-01

Highlights: • Limiting activity coefficients and gas–liquid partition coefficients for 30 VOCs were determined by GLC. • Solution thermodynamic quantities were derived and analyzed. • [MO-EMPYR][FAP] and [HO-EMIM][FAP] were identified as ILs of very low and very high cohesivity, respectively. • [HO-EMIM][FAP] is an IL of extreme H-bond acidity exhibiting superior performance for petrochemical separations. • Both studied [FAP] ILs were indicated to separate some azeotropic mixtures of alcohols with aprotic oxygenates. -- Abstract: Interactions of volatile organic compounds with two ionic liquids (ILs) containing tris(pentafluoroethyl)trifluorophosphate ([FAP]) anion and a functionalized cation, 1-(2-hydroxyethyl)-3-methylimidazolium ([HO-EMIM]) and 1-(2-methoxyethyl)-1-methylpyrrolidinium ([MO-EMPYR]), were explored through systematic GLC retention measurements. Infinite dilution activity coefficients γ 1 ∞ and gas–liquid partition coefficients K L of 30 selected solutes in [HO-EMIM][FAP] and [MO-EMPYR][FAP] were determined at five temperatures in the range from (318.15 to 353.15) K. Partial molar excess enthalpies and entropies at infinite dilution were derived from the temperature dependence of the γ 1 ∞ values. The Linear Free Energy Relationship (LFER) solvation model was used to correlate the K L values. The LFER correlation parameters and excess thermodynamic functions were analyzed to identify molecular interactions operating between the ILs and the individual solutes. By comparing the behaviors of the studied ILs and of their closely similar unfunctionalized analogs, net effects imparted by cation functionalization were also disclosed. The cohesivity of the two ILs was shown to differ dramatically: while [MO-EMPYR][FAP] ranks among ILs to the least cohesive, [HO-EMIM][FAP] belongs to the most cohesive ones. Both [HO-EMIM][FAP] and [MO-EMPYR][FAP] are capable of interacting with solutes specifically through dipolarity/polarizibility and

Ionic liquid foam floatation coupled with ionic liquid dispersive liquid-liquid microextraction for the separation and determination of estrogens in water samples by high-performance liquid chromatography with fluorescence detection.

Science.gov (United States)

Zhang, Rui; Wang, Chuanliu; Yue, Qiaohong; Zhou, Tiecheng; Li, Na; Zhang, Hanqi; Hao, Xiaoke

2014-11-01

An ionic liquid foam floatation coupled with ionic liquid dispersive liquid-liquid microextraction method was proposed for the extraction and concentration of 17-α-estradiol, 17-β-estradiol-benzoate, and quinestrol in environmental water samples by high-performance liquid chromatography with fluorescence detection. 1-Hexyl-3-methylimidazolium tetrafluoroborate was applied as foaming agent in the foam flotation process and dispersive solvent in microextraction. The introduction of the ion-pairing and salting-out agent NH4 PF6 was beneficial to the improvement of recoveries for the hydrophobic ionic liquid phase and analytes. Parameters of the proposed method including concentration of 1-hexyl-3-methylimidazolium tetrafluoroborate, flow rate of carrier gas, floatation time, types and concentration of ionic liquids, salt concentration in samples, extraction time, and centrifugation time were evaluated. The recoveries were between 98 and 105% with relative standard deviations lower than 7% for lake water and well water samples. The isolation of the target compounds from the water was found to be efficient, and the enrichment factors ranged from 4445 to 4632. This developing method is free of volatile organic solvents compared with regular extraction. Based on the unique properties of ionic liquids, the application of foam floatation, and dispersive liquid-liquid microextraction was widened. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A POLYMER-CERAMIC COMPOSITE MEMBRANE FOR RECOVERING VOLATILE ORGANIC COMPOUNDS FROM WASTEWATERS BY PERVAPORATION

Science.gov (United States)

A composite membrane was constructed on a porous ceramic support from a block copolymer of styrene and butadiene (SBS). It was tested in a laboratory pervaporation apparatus for recovering volatile organic compounds (VOCs) such a 1,1,1-trichloroethane (TCA) and trichloroethylene ...

Measurement of in-vehicle volatile organic compounds under static conditions.

Science.gov (United States)

You, Ke-wei; Ge, Yun-shan; Hu, Bin; Ning, Zhan-wu; Zhao, Shou-tang; Zhang, Yan-ni; Xie, Peng

2007-01-01

The types and quantities of volatile organic compounds (VOCs) inside vehicles have been determined in one new vehicle and two old vehicles under static conditions using the Thermodesorber-Gas Chromatograph/Mass Spectrometer (TD-GC/MS). Air sampling and analysis was conducted under the requirement of USEPA Method TO-17. A room-size, environment test chamber was utilized to provide stable and accurate control of the required environmental conditions (temperature, humidity, horizontal and vertical airflow velocity, and background VOCs concentration). Static vehicle testing demonstrated that although the amount of total volatile organic compounds (TVOC) detected within each vehicle was relatively distinct (4940 microg/m3 in the new vehicle A, 1240 microg/m3 in used vehicle B, and 132 microg/m3 in used vehicle C), toluene, xylene, some aromatic compounds, and various C7-C12 alkanes were among the predominant VOC species in all three vehicles tested. In addition, tetramethyl succinonitrile, possibly derived from foam cushions was detected in vehicle B. The types and quantities of VOCs varied considerably according to various kinds of factors, such as, vehicle age, vehicle model, temperature, air exchange rate, and environment airflow velocity. For example, if the airflow velocity increases from 0.1 m/s to 0.7 m/s, the vehicle's air exchange rate increases from 0.15 h(-1) to 0.67 h(-1), and in-vehicle TVOC concentration decreases from 1780 to 1201 microg/m3.

Recent Advances in Anhydrous Solvents for CO2 Capture: Ionic Liquids, Switchable Solvents, and Nanoparticle Organic Hybrid Materials

International Nuclear Information System (INIS)

Park, Youngjune; Lin, Kun-Yi Andrew; Park, Ah-Hyung Alissa; Petit, Camille

2015-01-01

CO 2 capture by amine scrubbing, which has a high CO 2 capture capacity and a rapid reaction rate, is the most employed and investigated approach to date. There are a number of recent large-scale demonstrations including the Boundary Dam Carbon Capture Project by SaskPower in Canada that have reported successful implementations of aqueous amine solvent in CO 2 capture from flue gases. The findings from these demonstrations will significantly advance the field of CO 2 capture in the coming years. While the latest efforts in aqueous amine solvents are exciting and promising, there are still several drawbacks to amine-based CO 2 capture solvents including high volatility and corrosiveness of the amine solutions as well as the high parasitic energy penalty during the solvent regeneration step. Thus, in a parallel effort, alternative CO 2 capture solvents, which are often anhydrous, have been developed as the third-generation CO 2 capture solvents. These novel classes of liquid materials include ionic liquids, CO 2 -triggered switchable solvents (i.e., CO 2 -binding organic liquids, reversible ionic liquids), and nanoparticle organic hybrid materials. This paper provides a review of these various anhydrous solvents and their potential for CO 2 capture. Particular attention is given to the mechanisms of CO 2 absorption in these solvents, their regeneration and their processability – especially taking into account their viscosity. While not intended to provide a complete coverage of the existing literature, this review aims at pointing the major findings reported for these new classes of CO 2 capture media.

Organic acids in naturally colored surface waters

Science.gov (United States)

Lamar, William L.; Goerlitz, D.F.

1966-01-01

Most of the organic matter in naturally colored surface waters consists of a mixture of carboxylic acids or salts of these acids. Many of the acids color the water yellow to brown; however, not all of the acids are colored. These acids range from simple to complex, but predominantly they are nonvolatile polymeric carboxylic acids. The organic acids were recovered from the water by two techniques: continuous liquid-liquid extraction with n-butanol and vacuum evaporation at 50?C (centigrade). The isolated acids were studied by techniques of gas, paper, and column chromatography and infrared spectroscopy. About 10 percent of the acids recovered were volatile or could be made volatile for gas chromatographic analysis. Approximately 30 of these carboxylic acids were isolated, and 13 of them were individually identified. The predominant part of the total acids could not be made volatile for gas chromatographic analysis. Infrared examination of many column chromatographic fractions indicated that these nonvolatile substances are primarily polymeric hydroxy carboxylic acids having aromatic and olefinic unsaturation. The evidence suggests that some of these acids result from polymerization in aqueous solution. Elemental analysis of the sodium fusion products disclosed the absence of nitrogen, sulfur, and halogens.

Prediction of (liquid + liquid) equilibrium for binary and ternary systems containing ionic liquids with the bis[(trifluoromethyl)sulfonyl]imide anion using the ASOG method

International Nuclear Information System (INIS)

Robles, Pedro A.; Cisternas, Luis A.

2015-01-01

Highlights: • ASOG model was used to predict LLE data for ionic liquid systems. • Twenty five binary and seven ternary systems that include the NTf 2 anion were used. • New group interaction parameters were determined. • The results are satisfactory, with rms deviations of about 3%. - Abstract: Ionic liquids are neoteric, environmentally friendly solvents (as they do not produce emissions) composed of large organic cations and relatively small inorganic anions. They have favorable physical properties, such as negligible volatility and a wide range of liquid existence. (Liquid + liquid) equilibrium (LLE) data for systems including ionic liquids, although essential for the design, optimization and operation of separation processes, remain scarce. However, some recent studies have presented ternary LLE data involving several ionic liquids and organic compounds such as alkanes, alkenes, alkanols, ethers and aromatics, as well as water. In this work, the ASOG model for the activity coefficient is used to predict LLE data for 25 binary and 07 ternary systems at 101.3 kPa and several temperatures; all the systems are formed by ionic liquids including the bis[(trifluoromethyl)sulfonyl]imide (NTf 2 ) anion plus alkanes, alkenes, cycloalkanes, alkanols, water, thiophene and aromatics. New group interaction parameters were determined using a modified Simplex method, minimizing a composition-based objective function of experimental data obtained from the literature. The results are satisfactory, with rms deviations of approximately 3%

Adsorption of volatile organic compounds by polytetra-fluor ethylene; Adsorption de composes organiques volatils par le polytetrafluor ethylene

Energy Technology Data Exchange (ETDEWEB)

Martinet, J.M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1958-07-01

The sorption of organic vapours by microporous polytetra-fluor ethylene has been studied gravimetrically using a Mc Bain-Baker type sorption balance. The amount of sorption, the peculiarities observed on the isotherm curves, the small influence of temperature, and smallness of hysteresis suggests that mainly physical adsorption occurs when the temperature is around 25 deg. C. The values of the surface areas obtained from the adsorption isotherms using organic vapours differ greatly from those derived from N{sub 2} adsorption measurements. This discrepancy cannot be completely attributed to differences in the structure and chemical function of the adsorbate molecules, or to the porous structure of the adsorbent. On the contrary, the surface area values obtained by sorbing high volatile freons conform with those measured by nitrogen adsorption, which seems to imply a connection between the area of sorbed monolayers and volatility of the adsorbate. (author) [French] La sorption de vapeurs organiques par du polytetrafluor ethylene microporeux a ete etudiee gravimetriquement a l'aide d'un appareillage du type balance de Mac Bain. La valeur de la masse adsorbee, les particularites observees dans la forme des isothermes, le peu d'influence de la temperature, la faiblesse de l'hysteresis suggerent l'intervention d'une adsorption physique, du moins au voisinage de 25 deg. C. Les isothermes relatives a l'absorption de vapeurs organiques conduisent a des valeurs de la surface specifique tres differentes de celles obtenues par adsorption d'azote. Ces divergences ne peuvent s'expliquer par la seule intervention de la structure moleculaire et de la fonction chimique de l'adsorbat, ni par la structure poreuse de l'adsorbant. Par contre, l'adsorption de freons tres volatils conduit a des valeurs de la surface specifique analogues a celles obtenues par adsorption d'azote ce qui semble etablir un lien entre la

Adsorption of volatile organic compounds by polytetra-fluor ethylene; Adsorption de composes organiques volatils par le polytetrafluor ethylene

Energy Technology Data Exchange (ETDEWEB)

Martinet, J M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1958-07-01

The sorption of organic vapours by microporous polytetra-fluor ethylene has been studied gravimetrically using a Mc Bain-Baker type sorption balance. The amount of sorption, the peculiarities observed on the isotherm curves, the small influence of temperature, and smallness of hysteresis suggests that mainly physical adsorption occurs when the temperature is around 25 deg. C. The values of the surface areas obtained from the adsorption isotherms using organic vapours differ greatly from those derived from N{sub 2} adsorption measurements. This discrepancy cannot be completely attributed to differences in the structure and chemical function of the adsorbate molecules, or to the porous structure of the adsorbent. On the contrary, the surface area values obtained by sorbing high volatile freons conform with those measured by nitrogen adsorption, which seems to imply a connection between the area of sorbed monolayers and volatility of the adsorbate. (author) [French] La sorption de vapeurs organiques par du polytetrafluor ethylene microporeux a ete etudiee gravimetriquement a l'aide d'un appareillage du type balance de Mac Bain. La valeur de la masse adsorbee, les particularites observees dans la forme des isothermes, le peu d'influence de la temperature, la faiblesse de l'hysteresis suggerent l'intervention d'une adsorption physique, du moins au voisinage de 25 deg. C. Les isothermes relatives a l'absorption de vapeurs organiques conduisent a des valeurs de la surface specifique tres differentes de celles obtenues par adsorption d'azote. Ces divergences ne peuvent s'expliquer par la seule intervention de la structure moleculaire et de la fonction chimique de l'adsorbat, ni par la structure poreuse de l'adsorbant. Par contre, l'adsorption de freons tres volatils conduit a des valeurs de la surface specifique analogues a celles obtenues par adsorption d'azote ce qui semble etablir un lien entre la volatilite de l'adsorbat et l'etendue des couches monomoleculaires

Investigations concerning the exchange of iodine from non-volatile organic iodine compounds

International Nuclear Information System (INIS)

Psarros, N.; Duschner, H.; Molzahn, D.; Schmidt, L.; Heise, S.; Jungclas, H.; Brandt, R.; Patzelt, P.

1990-10-01

The iodine produced by nuclear fission is removed during the reprocessing of exhausted nuclear fuel elements by desorption achieving good decontamination factors. Nevertheless the further optimization of the process requires detailed information about the iodine speciation during fuel reprocessing, and about possible reactions. For the study of decomposition reactions of iodo-alcanes, which are built up during the fuel recycling process, we developed a method for the synthesis of labelled iodo-dodecane, which was used as tracer. In order to identify the iodo species in the organic phase of the reprocessing cycle we applied plasma desorption time-of-flight mass spectroscopy. The problem of the volatility of the iodo-compounds in the ultra vacuum of the mass spectrometer was overcome by derivatization of the iodo-alcanes with dithizon, which yielded non-volatile ionic alcyltetrazolium iodides. Beta-spectrometric analysis of the exhaust condensates collected from the organic phase of the WAK reprocessing cycle revealed beside iodine-129 the existence of a low-energetic beta emitter, which has yet to be identified. A literature survey on the topic was also performed. (orig.) With 42 refs., 9 figs [de

Managing liquidity

DEFF Research Database (Denmark)

Pokutta, Sebastian; Schmaltz, Christian

2011-01-01

Large banking groups face the question of how to optimally allocate and generate liquidity: in a central liquidity hub or in many decentralized branches. We translate this question into a facility location problem under uncertainty. We show that volatility is the key driver behind (de......-)centralization. We provide an analytical solution for the 2-branch model and show that a liquidity center can be interpreted as an option on immediate liquidity. Therefore, its value can be interpreted as the price of information, i.e., the price of knowing the exact demand. Furthermore, we derive the threshold...... above which it is advantageous to open a liquidity center and show that it is a function of the volatility and the characteristic of the bank network. Finally, we discuss the n-branch model for real-world banking groups (10-60 branches) and show that it can be solved with high granularity (100 scenarios...

Measurement of the ambient organic aerosol volatility distribution: application during the Finokalia Aerosol Measurement Experiment (FAME-2008

Directory of Open Access Journals (Sweden)

B. H. Lee

2010-12-01

Full Text Available A variable residence time thermodenuder (TD was combined with an Aerodyne Aerosol Mass Spectrometer (AMS and a Scanning Mobility Particle Sizer (SMPS to measure the volatility distribution of aged organic aerosol in the Eastern Mediterranean during the Finokalia Aerosol Measurement Experiment in May of 2008 (FAME-2008. A new method for the quantification of the organic aerosol volatility distribution was developed combining measurements of all three instruments together with an aerosol dynamics model.

Challenges in the interpretation of ambient thermodenuder-AMS measurements include the potential resistances to mass transfer during particle evaporation, the effects of particle size on the evaporated mass fraction, the changes in the AMS collection efficiency and particle density as the particles evaporate partially in the TD, and finally potential losses inside the TD. Our proposed measurement and data analysis method accounts for all of these problems combining the AMS and SMPS measurements.

The AMS collection efficiency of the aerosol that passed through the TD was found to be approximately 10% lower than the collection efficiency of the aerosol that passed through the bypass. The organic aerosol measured at Finokalia is approximately 2 or more orders of magnitude less volatile than fresh laboratory-generated monoterpene (α-pinene, β-pinene and limonene under low NO_x conditions secondary organic aerosol. This low volatility is consistent with its highly oxygenated AMS mass spectrum. The results are found to be highly sensitive to the mass accommodation coefficient of the evaporating species. This analysis is based on the assumption that there were no significant reactions taking place inside the thermodenuder.

Study of gases and volatiles in samples of underground water bodies in the State of Mexico; Estudio de gases y volatiles en muestras de cuerpos de agua subterranea en el Estado de Mexico

Energy Technology Data Exchange (ETDEWEB)

Lopez R, N.; Segovia, N.; Cisniega, G.; Tamez, E. [Instituto Nacional de Investigaciones Nucleares, Gerencia de Ciencias Ambientales, A.P. 18-1027, C.P. 11801 Mexico D.F. (Mexico)

2000-07-01

It was realized a preliminary study of radon and volatile organic compounds (VOC ) in spring water of the State of Mexico. The radon was determined by the liquid scintillation method and the VOC by gas chromatography coupled to mass spectroscopy. The radon concentration range was between 0.50 - 4.42 KBq/m{sup 3}. Its were found some VOC of probably anthropogenic origin. (Author)

Emission index for evaluation of volatile organic compounds emitted from tomato plants in greenhouses

NARCIS (Netherlands)

Takayama, K.; Jansen, R.M.C.; Henten, van E.J.; Verstappen, F.W.A.; Bouwmeester, H.J.; Nishina, H.

2012-01-01

Measurement of volatile organic compounds (VOCs) emitted by plants allows us to monitor plant health status without touching the plant. To bring this technique a step further towards a practical plant diagnosis technique for greenhouse crop production, we have defined a numerical index named

Investigation of the organic matter in inactive nuclear tank liquids

International Nuclear Information System (INIS)

Schenley, R.L.; Griest, W.H.

1990-08-01

Environmental Protection Agency (EPA) methodology for regulatory organics fails to account for the organic matter that is suggested by total organic carbon (TOC) analysis in the Oak Ridge National Laboratory (ORNL) inactive nuclear waste-tank liquids and sludges. Identification and measurement of the total organics are needed to select appropriate waste treatment technologies. An initial investigation was made of the nature of the organics in several waste-tank liquids. This report details the analysis of ORNL wastes

Aqueous Oxidation of Green Leaf Volatiles as a Source of Secondary Organic Aerosol

Science.gov (United States)

Richards-Henderson, N. K.; Hansel, A.; Pham, A. T.; Vempati, H. S.; Valsaraj, K. T.; Anastasio, C.

2013-12-01

Vegetation emits volatile oxygenated hydrocarbons - the green leaf volatiles (GLVs) - which are formed from the biochemical conversion of linoleic and linolenic acids within plant cells. Stress or damage to vegetation can significantly elevate emission fluxes of these compounds, some of which are fairly water soluble. Aqueous-phase reactions of the GLVs with photochemically generated oxidants - such as hydroxyl radical (OH), singlet oxygen (1O2) and excited triplet states of organic compounds (3C*) _ might then form low-volatility products that can act as secondary organic aerosol (SOA). In order to determine if GLVs can be a significant source of secondary organic carbon in fogwater, studies of GLVs in laboratory solutions are needed to elucidate the oxidation kinetics and the corresponding SOA mass yields. In this study we are determining the second-order rate constants, and SOA mass yields, for five GLVs (cis-3-hexen-1-ol, cis-3-hexenylacetate, methyl salicylate, methyl jasmonate, and 2-methyl-3-butene-2-ol) reacting with OH,1O2 and 3C*. Experiments are performed at relevant fog water pHs, temperatures, and oxidant concentrations. Rate constants are determined using a relative rate approach in which the decay of GLVs and reference compounds are monitored as function of time by HPLC. The capacity of GLVs to form aqueous SOA was determined by following the formation of their decomposition products with HPLC-UV/DAD and HPLC-ESI/MS. SOA mass yields are measured gravimetrically from laboratory solutions containing atmospherically relevant concentrations of photooxidants and GLVs, and irradiated with simulated sunlight. We will use our results to assess the potential contribution of aqueous GLV reactions as a source of SOA in cloudy or foggy atmospheres.

Sub-chronic toxicity of low concentrations of industrial volatile organic pollutants in vitro

International Nuclear Information System (INIS)

McDermott, Catherine; Allshire, Ashley; Pelt, Frank N.A.M. van; Heffron, James J.A.

2007-01-01

Organic solvents form an important class of pollutants in the ambient air and have been associated with neurotoxicity and immunotoxicity in humans. Here we investigated the biological effects of sub-chronic exposure to industrially important volatile organic solvents in vitro. Jurkat T cells were exposed to toluene, n-hexane and methyl ethyl ketone (MEK) individually for 5 days and solvent exposure levels were confirmed by headspace gas chromatography. A neuroblastoma cell line (SH-SY5Y) was exposed to toluene for the same period. Following exposure, cells were harvested and toxicity measured in terms of the following endpoints: membrane damage (LDH leakage), perturbations in intracellular free Ca 2+ , changes in glutathione redox status and dual-phosphorylation of MAP kinases ERK1/2, JNK and p38. The results show that sub-chronic exposure to the volatile organic solvents causes membrane damage, increased intracellular free calcium and altered glutathione redox status in both cell lines. However, acute and sub-chronic solvent exposure did not result in MAP kinase phosphorylation. Toxicity of the solvents tested increased with hydrophobicity. The lowest-observed-adverse-effect-levels (LOAELs) measured in vitro were close to blood solvent concentrations reported for individuals exposed to the agents at levels at or below their individual threshold limit values (TLVs)

Development and validation of a portable gas phase standard generation and calibration system for volatile organic compounds

Science.gov (United States)

P. Veres; J. B. Gilman; J. M. Roberts; W. C. Kuster; C. Warneke; I. R. Burling; J. de Gouw

2010-01-01

We report on the development of an accurate, portable, dynamic calibration system for volatile organic compounds (VOCs). The Mobile Organic Carbon Calibration System (MOCCS) combines the production of gas-phase VOC standards using permeation or diffusion sources with quantitative total organic carbon (TOC) conversion on a palladium surface to CO2 in the presence of...

Priority volatile organic compounds in surface waters of the southern North Sea

International Nuclear Information System (INIS)

Huybrechts, Tom; Dewulf, Jo; Langenhove, Herman van

2005-01-01

The occurrence of 25 volatile organic compounds (VOCs) was studied from April 1998 to October 2000 in the southern North Sea. Target VOCs were selected from lists of priority pollutants for the marine environment and included, e.g., chlorinated short-chain hydrocarbons (CHCs), monocyclic aromatic hydrocarbons (MAHs), and chlorinated monocyclic aromatic hydrocarbons (CMAHs). Water samples were taken from the Channel, the Belgian Continental Shelf, the mouth of the Scheldt estuary and the Southern Bight, and were analysed by purge-and-trap and high-resolution gas chromatography-mass spectrometry. All data were produced by analyses deemed 'in control' by a rigorous quality assurance/quality control program provided by QUASIMEME (Quality Assurance of Information for Marine Environmental Monitoring in Europe). Chloroform and trichloroethene were commonly detected at concentrations up to 1900 and 270 ng l -1 , respectively. The other CHCs were generally found below 5 ng l -1 , and rarely exceeded 10 ng l -1 . Concentrations of MAHs were at least one order of magnitude higher than those of the CHCs. The higher levels were attributed to anthropogenic emissions from oil-related activities in coastal areas. CMAHs, except chlorobenzene and 1,4-dichlorobenzene, were hardly detected in North Sea waters. The levels of several CHCs and MAHs were shown to decrease compared to previous investigations in 1994-1995, probably as a result of on-going emission reduction efforts. The occurrence of 1,1,1-trichloroethane, for instance, was substantially reduced since the Montreal Protocol was implemented in 1995. - Volatile aromatics are a major group of volatile organic compounds in the North Sea, and are attributed to discharges from shipping and oil related activities

Metabolism of 210Po in rats: Volatile 210Po from faeces

International Nuclear Information System (INIS)

Sadi, B. B.; Li, C.; Wyatt, H.; Bugden, M.; Wilkinson, D.; Kramer, G.

2011-01-01

The metabolic formation of volatile 210 Po species in a rat that was intravenously administered with 210 Po-citrate was investigated in this study. A slurry of the faecal sample was prepared in water and was bubbled with nitrogen gas in a closed system. The discharged gas was passed through a trapping device filled with liquid scintillation cocktail in order to capture any volatile 210 Po species. The amount of 210 Po trapped in the scintillation cocktail was measured by a liquid scintillation analyser that provided evidence of the presence of volatile 210 Po species in the faeces. The presence of volatile 210 Po in the faeces indicates that the metabolic formation of volatile 210 Po is likely to occur in the gut due to bacterial activity. The amount of volatile 210 Po species was compared with the daily faecal excretion of 210 Po. After 2 h of bubbling, the volatile 210 Po collected from the faeces sample was found to be between 1.0 and 1.7 % of the daily faecal excretion for the 4 d following 210 Po-citrate administration. (authors)

Comparative evaluation of volatiles, phenolics, sugars, organic acids and antioxidant properties of Sel-42 and Tainung papaya varieties.

Science.gov (United States)

Kelebek, Hasim; Selli, Serkan; Gubbuk, Hamide; Gunes, Esma

2015-04-15

The present study was designed to determine the phenolic compounds, organic acids, sugars, aroma profiles and antioxidant properties of Sel-42 and Tainung papayas grown in Turkey. High-performance liquid chromatography/electrospray ionisation tandem mass spectrometry (HPLC-ESI-MS/MS) method was used for the phenolic compounds analysis. Twelve phenolic compounds were identified and quantified in the samples. The total phenolic content of Sel-42 was clearly higher than that of Tainung. Protocatechuic acid-hexoside, gallic acid-deoxyhexoside, ferulic acid and chlorogenic acids were the most abundant phenolics in both cultivars. Aroma composition of papaya was analysed by gas chromatography-mass spectrometry (GC-MS). A total of 46 and 42 aroma compounds, including esters, alcohols, terpenes, lactones, acids, carbonyl compounds, and volatile phenols were identified in the Sel-42 and Tainung, respectively. The significant linear correlation was confirmed between the values for the total phenolic content and antioxidant activity of papaya extracts. Copyright © 2014 Elsevier Ltd. All rights reserved.

Phase Behavior of Mixtures of Ionic Liquids and Organic Solvents

DEFF Research Database (Denmark)

Abildskov, Jens; Ellegaard, Martin Dela; O’Connell, J.P.

2010-01-01

A corresponding-states form of the generalized van der Waals equation, previously developed for mixtures of an ionic liquid and a supercritical solute, is here extended to mixtures including an ionic liquid and a solvent (water or organic). Group contributions to characteristic parameters...... are implemented, leading to an entirely predictive method for densities of mixed compressed ionic liquids. Quantitative agreement with experimental data is obtained over wide ranges of conditions. Previously, the method has been applied to solubilities of sparingly soluble gases in ionic liquids and in organic...... solvents. Here we show results for heavier and more-than-sparingly solutes such as carbon dioxide and propane in ionic liquids....

Efficiency of biological activator formulated material (BAFM) for volatile organic compounds removal--preliminary batch culture tests with activated sludge.

Science.gov (United States)

Corre, Charline; Couriol, Catherine; Amrane, Abdeltif; Dumont, Eric; Andrès, Yves; Le Cloirec, Pierre

2012-01-01

During biological degradation, such as biofiltration of air loaded with volatile organic compounds, the pollutant is passed through a bed packed with a solid medium acting as a biofilm support. To improve microorganism nutritional equilibrium and hence to enhance the purification capacities, a Biological Activator Formulated Material (BAFM) was developed, which is a mixture of solid nutrients dissolving slowly in a liquid phase. This solid was previously validated on mineral pollutants: ammonia and hydrogen sulphide. To evaluate the efficiency of such a material for biodegradation of some organic compounds, a simple experiment using an activated sludge batch reactor was carried out. The pollutants (sodium benzoate, phenol, p-nitrophenol and 2-4-dichlorophenol) were in the concentration range 100 to 1200 mg L(-1). The positive impact of the formulated material was shown. The improvement of the degradation rates was in the range 10-30%. This was the consequence of the low dissolution of the nutrients incorporated during material formulation, followed by their consumption by the biomass, as shown for urea used as a nitrogen source. Owing to its twofold interest (mechanical resistance and nutritional supplementation), the Biological Activator Formulated Material seems to be a promising material. Its addition to organic or inorganic supports should be investigated to confirm its relevance for implementation in biofilters.

Volatile fatty acids production from sewage organic matter by combined bioflocculation and anaerobic fermentation

NARCIS (Netherlands)

Khiewwijit, R.; Keesman, K.J.; Rijnaarts, H.H.M.; Temmink, B.G.

2014-01-01

This work aims at exploring the feasibility of a combined process bioflocculation to concentrate sewage organic matter and anaerobic fermentation to produce volatile fatty acids (VFA). Bioflocculation, using a high-loaded aerobic membrane bioreactor (HL-MBR), was operated at an HRT of 1 h and an SRT

Removal of H2S and volatile organic sulfur compounds by silicone membrane extraction

NARCIS (Netherlands)

Manconi, I.; Lens, P.N.L.

2009-01-01

BACKGROUND: This study explores an alternative process for the abatement and/or desulfurization of H2S and volatile organic sulfur compounds (VOSC) containing waste streams, which employs a silicone-based membrane to simultaneously remove H2S and VOSC. An extractive membrane reactor allows the

The liquidity of the Organic movement - reconversion or reillumination

DEFF Research Database (Denmark)

Kristensen, Niels Heine

2005-01-01

Kristensen NH (2005): The liquidity of the Organic movement - reconversion or reillumination. Paper presented at Working Group 5 at the XXI Congress of the ESRS 22-27 August, 2005 Keszthely, Hungary......Kristensen NH (2005): The liquidity of the Organic movement - reconversion or reillumination. Paper presented at Working Group 5 at the XXI Congress of the ESRS 22-27 August, 2005 Keszthely, Hungary...

Neurotoxicity of fungal volatile organic compounds in Drosophila melanogaster.

Science.gov (United States)

Inamdar, Arati A; Masurekar, Prakash; Bennett, Joan Wennstrom

2010-10-01

Many volatile organic compounds (VOCs) are found in indoor environment as products of microbial metabolism. In damp indoor environments, fungi are associated with poor air quality. Some epidemiological studies have suggested that microbial VOCs have a negative impact on human health. Our study was designed to provide a reductionist approach toward studying fungal VOC-mediated toxicity using the inexpensive model organism, Drosophila melanogaster, and pure chemical standards of several important fungal VOCs. Low concentrations of the following known fungal VOCs, 0.1% of 1-octen-3-ol and 0.5% of 2-octanone; 2,5 dimethylfuran; 3-octanol; and trans-2-octenal, caused locomotory defects and changes in green fluorescent protein (GFP)- and antigen-labeled dopaminergic neurons in adult D. melanogaster. Locomotory defects could be partially rescued with L-DOPA. Ingestion of the antioxidant, vitamin E, improved the survival span and delayed the VOC-mediated changes in dopaminergic neurons, indicating that the VOC-mediated toxicity was due, in part, to generation of reactive oxygen species.

Nicotine, aerosol particles, carbonyls and volatile organic compounds in tobacco- and menthol-flavored e-cigarettes.

Science.gov (United States)

Lee, Mi-Sun; LeBouf, Ryan F; Son, Youn-Suk; Koutrakis, Petros; Christiani, David C

2017-04-27

We aimed to assess the content of electronic cigarette (EC) emissions for five groups of potentially toxic compounds that are known to be present in tobacco smoke: nicotine, particles, carbonyls, volatile organic compounds (VOCs), and trace elements by flavor and puffing time. We used ECs containing a common nicotine strength (1.8%) and the most popular flavors, tobacco and menthol. An automatic multiple smoking machine was used to generate EC aerosols under controlled conditions. Using a dilution chamber, we targeted nicotine concentrations similar to that of exposure in a general indoor environment. The selected toxic compounds were extracted from EC aerosols into a solid or liquid phase and analyzed with chromatographic and spectroscopic methods. We found that EC aerosols contained toxic compounds including nicotine, fine and nanoparticles, carbonyls, and some toxic VOCs such as benzene and toluene. Higher mass and number concentrations of aerosol particles were generated from tobacco-flavored ECs than from menthol-flavored ECs. We found that diluted machine-generated EC aerosols contain some pollutants. These findings are limited by the small number of ECs tested and the conditions of testing. More comprehensive research on EC exposure extending to more brands and flavor compounds is warranted.

Imaging subsurface geology and volatile organic compound plumes

International Nuclear Information System (INIS)

Qualheim, B.J.; Daley, P.F.; Johnson, V.; McPherrin, R.V.; Laguna, G.

1992-03-01

Lawrence Livermore National Laboratory (LLNL) (Fig. 1) is in the final stages of the Superfund decisionmaking process for site remediation and restoration. In the process of characterizing the subsurface of the LLNL site, we have developed unique methods of collecting, storing, retrieving, and imaging geologic and chemical data from more than 350 drill holes. The lateral and vertical continuity of subsurface paleostream channels were mapped for the entire LLNL site using geologic descriptions from core samples, cuttings, and interpretations from geophysical logs. A computer-aided design and drafting program, SLICE, written at LLNL, was used to create two-dimensional maps of subsurface sediments, and state-of-the-art software produced three-dimensional images of the volatile organic compound (VOC) plumes using data from water and core fluid analyses

Promotion of plant growth by Pseudomonas fluorescens strain SS101 via novel volatile organic compounds

NARCIS (Netherlands)

Park, Yong-Soon; Dutta, Swarnalee; Ann, Mina; Raaijmakers, Jos M.; Park, Kyungseok

2015-01-01

Abstract Volatile organic compounds (VOCs) from plant growth-promoting rhizobacteria (PGPR) play key roles in modulating plant growth and induced systemic resistance (ISR) to pathogens. Despite their significance, the physiological functions of the specific VOCs produced by Pseudomonas fluorescens

Ionic liquids used in extraction and separation of metal ions

International Nuclear Information System (INIS)

Shen Xinghai; Xu Chao; Liu Xinqi; Chu Taiwei

2006-01-01

Ionic liquids as green solvents now have become a research hotspot in the field of separation of metal ions by solvent extraction. Experimental results of extraction of various metal ions with ionic liquids as solvents, including that of alkali metals, alkaline earths, transition metals rare earths and actinides are introduced. The extraction of uranium, plutonium and fission products that are involved in spent nuclear fuel reprocessing is also reviewed. The possible extraction mechanisms are discussed. Finally, the prospect of replacement of volatile and/or toxic organic solvents with environmentally benign ionic liquids for solvent extraction and the potency of applications of ionic liquids in solvent extraction are also commented. (authors)

Untargeted metabolomic analysis using liquid chromatography quadrupole time-of-flight mass spectrometry for non-volatile profiling of wines

International Nuclear Information System (INIS)

Arbulu, M.; Sampedro, M.C.; Gómez-Caballero, A.; Goicolea, M.A.; Barrio, R.J.

2015-01-01

Highlights: • An untargeted metabolomic method for the non-volatile profile of the Graciano wine was developed. • 411 different metabolites in Graciano Vitis vinifera red wine were identified. • 15 compounds could serve to differentiate Graciano and Tempranillo wines. • An enological database (WinMet) with 2080 compounds was constructed. - Abstract: The current study presents a method for comprehensive untargeted metabolomic fingerprinting of the non-volatile profile of the Graciano Vitis vinifera wine variety, using liquid chromatography/electrospray ionization time of flight mass spectrometry (LC–ESI-QTOF). Pre-treatment of samples, chromatographic columns, mobile phases, elution gradients and ionization sources, were evaluated for the extraction of the maximum number of metabolites in red wine. Putative compounds were extracted from the raw data using the extraction algorithm, molecular feature extractor (MFE). For the metabolite identification the WinMet database was designed based on electronic databases and literature research and includes only the putative metabolites reported to be present in oenological matrices. The results from WinMet were compared with those in the METLIN database to evaluate how much the databases overlap for performing identifications. The reproducibility of the analysis was assessed using manual processing following replicate injections of Vitis vinifera cv. Graciano wine spiked with external standards. In the present work, 411 different metabolites in Graciano Vitis vinifera red wine were identified, including primary wine metabolites such as sugars (4%), amino acids (23%), biogenic amines (4%), fatty acids (2%), and organic acids (32%) and secondary metabolites such as phenols (27%) and esters (8%). Significant differences between varieties Tempranillo and Graciano were related to the presence of fifteen specific compounds

Untargeted metabolomic analysis using liquid chromatography quadrupole time-of-flight mass spectrometry for non-volatile profiling of wines

Energy Technology Data Exchange (ETDEWEB)

Arbulu, M. [Department of Analytical Chemistry, Faculty of Pharmacy, University of the Basque Country, 01006 Vitoria-Gasteiz (Spain); Sampedro, M.C. [Central Service of Analysis, SGIker, University of the Basque Country, 01006 Vitoria-Gasteiz (Spain); Gómez-Caballero, A.; Goicolea, M.A. [Department of Analytical Chemistry, Faculty of Pharmacy, University of the Basque Country, 01006 Vitoria-Gasteiz (Spain); Barrio, R.J., E-mail: r.barrio@ehu.es [Department of Analytical Chemistry, Faculty of Pharmacy, University of the Basque Country, 01006 Vitoria-Gasteiz (Spain)

2015-02-09

Highlights: • An untargeted metabolomic method for the non-volatile profile of the Graciano wine was developed. • 411 different metabolites in Graciano Vitis vinifera red wine were identified. • 15 compounds could serve to differentiate Graciano and Tempranillo wines. • An enological database (WinMet) with 2080 compounds was constructed. - Abstract: The current study presents a method for comprehensive untargeted metabolomic fingerprinting of the non-volatile profile of the Graciano Vitis vinifera wine variety, using liquid chromatography/electrospray ionization time of flight mass spectrometry (LC–ESI-QTOF). Pre-treatment of samples, chromatographic columns, mobile phases, elution gradients and ionization sources, were evaluated for the extraction of the maximum number of metabolites in red wine. Putative compounds were extracted from the raw data using the extraction algorithm, molecular feature extractor (MFE). For the metabolite identification the WinMet database was designed based on electronic databases and literature research and includes only the putative metabolites reported to be present in oenological matrices. The results from WinMet were compared with those in the METLIN database to evaluate how much the databases overlap for performing identifications. The reproducibility of the analysis was assessed using manual processing following replicate injections of Vitis vinifera cv. Graciano wine spiked with external standards. In the present work, 411 different metabolites in Graciano Vitis vinifera red wine were identified, including primary wine metabolites such as sugars (4%), amino acids (23%), biogenic amines (4%), fatty acids (2%), and organic acids (32%) and secondary metabolites such as phenols (27%) and esters (8%). Significant differences between varieties Tempranillo and Graciano were related to the presence of fifteen specific compounds.

Biogenic volatile emissions from the soil.

Science.gov (United States)

Peñuelas, J; Asensio, D; Tholl, D; Wenke, K; Rosenkranz, M; Piechulla, B; Schnitzler, J P

2014-08-01

Volatile compounds are usually associated with an appearance/presence in the atmosphere. Recent advances, however, indicated that the soil is a huge reservoir and source of biogenic volatile organic compounds (bVOCs), which are formed from decomposing litter and dead organic material or are synthesized by underground living organism or organs and tissues of plants. This review summarizes the scarce available data on the exchange of VOCs between soil and atmosphere and the features of the soil and particle structure allowing diffusion of volatiles in the soil, which is the prerequisite for biological VOC-based interactions. In fact, soil may function either as a sink or as a source of bVOCs. Soil VOC emissions to the atmosphere are often 1-2 (0-3) orders of magnitude lower than those from aboveground vegetation. Microorganisms and the plant root system are the major sources for bVOCs. The current methodology to detect belowground volatiles is described as well as the metabolic capabilities resulting in the wealth of microbial and root VOC emissions. Furthermore, VOC profiles are discussed as non-destructive fingerprints for the detection of organisms. In the last chapter, belowground volatile-based bi- and multi-trophic interactions between microorganisms, plants and invertebrates in the soil are discussed. © 2014 John Wiley & Sons Ltd.

Study of gases and volatiles in samples of underground water bodies in the State of Mexico

International Nuclear Information System (INIS)

Lopez R, N.; Segovia, N.; Cisniega, G.; Tamez, E.

2000-01-01

It was realized a preliminary study of radon and volatile organic compounds (VOC ) in spring water of the State of Mexico. The radon was determined by the liquid scintillation method and the VOC by gas chromatography coupled to mass spectroscopy. The radon concentration range was between 0.50 - 4.42 KBq/m 3 . Its were found some VOC of probably anthropogenic origin. (Author)

Emission of the main biogenic volatile organic compounds in France

International Nuclear Information System (INIS)

Luchetta, L.; Simon, V.; Torres, L.

2000-01-01

An estimation of biogenic emissions of the main non-methanic Volatile Organic Compounds (VOCs) due to the forest cover in France has been realized. 32 species representing 98% of French forest have been considered for the estimation. The latter dealt on a net made of 93 irregular spatial grids (Departments) with an average size of 75 km x 75 km. We assigned emission rates and foliar biomass densities specific to each of the 32 species. The environmental variables (temperature, light intensity) have been collected for the whole of French Departments. A special effort was extended so as to use ''Guenther's'' calculation algorithms, and specific emitting factors to species growing in France or in bordering countries. Along the way of the five years (1994-1998) of the study we have calculated the yearly mean of isoprene, mono-terpenes and Other Volatile Organic Compounds (OVOCs) emissions on the scale of the French Departments. At the national level isoprene emission is reckoned at 457 kt yr -1 and represents nearly 49% of the total emission, whereas mono-terpenes with 350 kt yr -1 and OVOCs with 129 kt yr -1 represent respectively 37% and 14% of the total. The yearly biogenic emission of VOCs in France represents virtually half the anthropic source. However in some regions (Mediterranean area) natural emissions can widely exceed anthropic emissions during certain periods. Let's note the whole of our results remains tinged with a great uncertainty because the estimations carried out are presented with correction factors that can reach values comprised between 4 and 7. (author)

Polycyclic aromatic hydrocarbons and volatile organic compounds in biochar and biochar-amended soil: A review

Science.gov (United States)

Residual pollutants including polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs), and carbon(aceous) nanoparticles are inevitably generated during the pyrolysis of waste biomass, and remain on the solid co-product called biochar. Such pollutants could have adverse effects on ...

Microbial Volatile Organic Compound Emissions from Stachybotrys chartarum growing on Gypsum Wallboard and Ceiling tile

Science.gov (United States)

This study compared seven toxigenic strains of S. chartarum found in water-damaged buildings to characterize the microbial volatile organic compound (MVOC) emissions profile while growing on gypsum wallboard (W) and ceiling tile (C) coupons. The inoculated coupons with their sub...

Removal of gasoline volatile organic compounds via air biofiltration

International Nuclear Information System (INIS)

Miller, R.S.; Saberiyan, A.G.; Esler, C.T.; DeSantis, P.; Andrilenas, J.S.

1995-01-01

Volatile organic compounds (VOCs) generated by vapor extraction and air-stripping systems can be biologically treated in an air biofiltration unit. An air biofilter consists of one or more beds of packing material inoculated with heterotrophic microorganisms capable of degrading the organic contaminant of concern. Waste gases and oxygen are passed through the inoculated packing material, where the microorganisms will degrade the contaminant and release CO 2 + H 2 O. Based on data obtained from a treatability study, a full-scale unit was designed and constructed to be used for treating gasoline vapors generated by a vapor-extraction and groundwater-treatment system at a site in California. The unit is composed of two cylindrical reactors with a total packing volume of 3 m 3 . Both reactors are packed with sphagnum moss and inoculated with hydrocarbon-degrading microorganisms of Pseudomonas and Arthrobacter spp. The two reactors are connected in series for air-flow passage. Parallel lines are used for injection of water, nutrients, and buffer to each reactor. Data collected during the startup program have demonstrated an air biofiltration unit with high organic-vapor-removal efficiency

Study on off-odor volatiles of irradiated packaged raw pork

International Nuclear Information System (INIS)

Lin Ruotai; Geng Shengrong; Liu Yangmin

2008-01-01

Analysing the compositions of off-odor volatiles in irradiated refrigerated vacuum-packaged pork and research on its origin. First, the off-odor volatiles were collected by a cooled via in liquid nitrogen, then the main composition of off-odor volatiles were analyzed by gas chromatograph mass spectrometry (GC-MS). The main composition of off-odor volatiles are dimethyl disulfide, dimethyl sulfide, dimethyl trisulfide, methanethiol and S-methyl thioacetate. The off-odor volatiles come from irradiated cystine, methionine and VB1. The main composition of off-odor volatiles are S-containing compounds from irradiated S-containing amino acid and VB1

Solidification of oils and organic liquids

International Nuclear Information System (INIS)

Clark, D.E.; Colombo, P.; Neilson, R.M. Jr.

1982-07-01

The suitability of selected solidification media for application in the disposal of low-level oil and other organic liquid wastes has been investigated. In the past, these low-level wastes (LLWs) have commonly been immobilized by sorption onto solid absorbents such as vermiculite or diatomaceous earth. Evolving regulations regarding the disposal of these materials encourage solidification. Solidification media which were studied include Portland type I cement; vermiculite plus Portland type I cement; Nuclear Technology Corporation's Nutek 380-cement process; emulsifier, Portland type I cement-sodium silicate; Delaware Custom Materiel's cement process; and the US Gypsum Company's Envirostone process. Waste forms have been evaluated as to their ability to reliably produce free standing monolithic solids which are homogeneous (macroscopically), contain < 1% free standing liquids by volume and pass a water immersion test. Solidified waste form specimens were also subjected to vibratory shock testing and flame testing. Simulated oil wastes can be solidified to acceptable solid specimens having volumetric waste loadings of less than 40 volume-%. However, simulated organic liquid wastes could not be solidified into acceptable waste forms above a volumetric loading factor of about 10 volume-% using the solidification agents studied

Microbial communities related to volatile organic compound emission in automobile air conditioning units.

Science.gov (United States)

Diekmann, Nina; Burghartz, Melanie; Remus, Lars; Kaufholz, Anna-Lena; Nawrath, Thorben; Rohde, Manfred; Schulz, Stefan; Roselius, Louisa; Schaper, Jörg; Mamber, Oliver; Jahn, Dieter; Jahn, Martina

2013-10-01

During operation of mobile air conditioning (MAC) systems in automobiles, malodours can occur. We studied the microbial communities found on contaminated heat exchanger fins of 45 evaporators from car MAC systems which were operated in seven different regions of the world and identified corresponding volatile organic compounds. Collected biofilms were examined by scanning electron microscopy and fluorescent in situ hybridization. The detected bacteria were loosely attached to the metal surface. Further analyses of the bacteria using PCR-based single-strand conformation polymorphism and sequencing of isolated 16S rRNA gene fragments identified highly divergent microbial communities with multiple members of the Alphaproteobacteriales, Methylobacteria were the prevalent bacteria. In addition, Sphingomonadales, Burkholderiales, Bacillales, Alcanivorax spp. and Stenotrophomonas spp. were found among many others depending on the location the evaporators were operated. Interestingly, typical pathogenic bacteria related to air conditioning systems including Legionella spp. were not found. In order to determine the nature of the chemical compounds produced by the bacteria, the volatile organic compounds were examined by closed loop stripping analysis and identified by combined gas chromatography/mass spectrometry. Sulphur compounds, i.e. di-, tri- and multiple sulphides, acetylthiazole, aromatic compounds and diverse substituted pyrazines were detected. Mathematical clustering of the determined microbial community structures against their origin identified a European/American/Arabic cluster versus two mainly tropical Asian clusters. Interestingly, clustering of the determined volatiles against the origin of the corresponding MAC revealed a highly similar pattern. A close relationship of microbial community structure and resulting malodours to the climate and air quality at the location of MAC operation was concluded.

Multiwalled carbon nanotubes sensor for organic liquid detection at room temperature

Science.gov (United States)

Chaudhary, Deepti; Khare, Neeraj; Vankar, V. D.

2016-04-01

We have explored the possibility of using multiwalled carbon nanotubes (MWCNTs) as room temperature chemical sensor for the detection of organic liquids such as ethanol, propanol, methanol and toluene. MWCNTs were synthesized by thermal chemical vapor deposition (TCVD) technique. The interdigitated electrodes were fabricated by conventional photolithography technique. The sensor was fabricated by drop depositing MWCNT suspension onto the interdigitated electrodes. The sensing properties of MWCNTs sensor was studied for organic liquids detection. The resistance of sensor was found to increase upon exposure to these liquids. Sensor shows good reversibility and fast response at room temperature. Charge transfer between the organic liquid and sensing element is the dominant sensing mechanism.

NOCHAR Polymers: An Aqueous and Organic Liquid Solidification Process for Cadarache LOR (Liquides Organiques Radioactifs) - 13195

International Nuclear Information System (INIS)

Vaudey, Claire-Emilie; Renou, Sebastien; Porco, Julien; Kelley, Dennis; Cochaud, Chantal; Serrano, Roger

2013-01-01

To handle the Very Low Level Waste (VLLW) and the Low Level Waste (LLW) in France, two options can be considered: the incineration at CENTRACO facility and the disposal facility on ANDRA sites. The waste acceptance in these radwaste routes is dependent upon the adequacy between the waste characteristics (physical chemistry and radiological) and the radwaste route specifications. If the waste characteristics are incompatible with the radwaste route specifications (presence of significant quantities of chlorine, fluorine, organic component etc or/and high activity limits), it is necessary to find an alternative solution that consists of a waste pre-treatment process. In the context of the problematic Cadarache LOR (Liquides Organiques Radioactifs) waste streams, two radioactive scintillation cocktails have to be treated. The first one is composed of organic liquids at 13.1 % (diphenyloxazol, mesitylene, TBP, xylene) and water at 86.9 %. The second one is composed of TBP at 8.6 % and water at 91.4 %. They contain chlorine, fluorine and sulphate and have got alpha/beta/gamma spectra with mass activities equal to some kBq.g -1 . Therefore, tritium is present and creates the second problematic waste stream. As a consequence, in order for disposal acceptance at the ANDRA site, it is necessary to pre-treat the waste. The NOCHAR polymers as an aqueous and organic liquid solidification process seem to be an adequate solution. Indeed, these polymers constitute an important variety of products applied to the treatment of radioactive aqueous and organic liquids (solvent, oil, solvent/oil mixing etc) and sludge through a mechanical and chemical solidification process. For Cadarache LOR, N910 and N960 respectively dedicated to the organic and aqueous liquids solidification are considered. With the N910, the organic waste solidification occurs in two steps. As the organic liquid travels moves through the polymer strands, the strands swell and immobilise the liquid. Then as the

Nitrate radicals and biogenic volatile organic compounds: oxidation, mechanisms, and organic aerosol

Energy Technology Data Exchange (ETDEWEB)

Ng, Nga Lee; Brown, Steven S.; Archibald, Alexander T.; Atlas, Elliot; Cohen, Ronald C.; Crowley, John N.; Day, Douglas A.; Donahue, Neil M.; Fry, Juliane L.; Fuchs, Hendrik; Griffin, Robert J.; Guzman, Marcelo I.; Herrmann, Hartmut; Hodzic, Alma; Iinuma, Yoshiteru; Jimenez, José L.; Kiendler-Scharr, Astrid; Lee, Ben H.; Luecken, Deborah J.; Mao, Jingqiu; McLaren, Robert; Mutzel, Anke; Osthoff, Hans D.; Ouyang, Bin; Picquet-Varrault, Benedicte; Platt, Ulrich; Pye, Havala O. T.; Rudich, Yinon; Schwantes, Rebecca H.; Shiraiwa, Manabu; Stutz, Jochen; Thornton, Joel A.; Tilgner, Andreas; Williams, Brent J.; Zaveri, Rahul A.

2017-01-01

Oxidation of biogenic volatile organic compounds (BVOC) by the nitrate radical (NO₃) represents one of the important interactions between anthropogenic emissions related to combustion and natural emissions from the biosphere. This interaction has been recognized for more than 3 decades, during which time a large body of research has emerged from laboratory, field, and modeling studies. NO₃-BVOC reactions influence air quality, climate and visibility through regional and global budgets for reactive nitrogen (particularly organic nitrates), ozone, and organic aerosol. Despite its long history of research and the significance of this topic in atmospheric chemistry, a number of important uncertainties remain. These include an incomplete understanding of the rates, mechanisms, and organic aerosol yields for NO₃-BVOC reactions, lack of constraints on the role of heterogeneous oxidative processes associated with the NO₃ radical, the difficulty of characterizing the spatial distributions of BVOC and NO₃ within the poorly mixed nocturnal atmosphere, and the challenge of constructing appropriate boundary layer schemes and non-photochemical mechanisms for use in state-of-the-art chemical transport and chemistry–climate models.

This review is the result of a workshop of the same title held at the Georgia Institute of Technology in June 2015. The first half of the review summarizes the current literature on NO₃-BVOC chemistry, with a particular focus on recent advances in instrumentation and models, and in organic nitrate and secondary organic aerosol (SOA) formation chemistry. Building on this current understanding, the second half of the review outlines impacts of NO₃-BVOC chemistry on air quality and climate, and suggests critical research needs to better constrain this interaction to improve the predictive capabilities of atmospheric models.

Arsenic biotransformation and volatilization in transgenic rice

Science.gov (United States)

Meng, Xiang-Yan; Qin, Jie; Wang, Li-Hong; Duan, Gui-Lan; Sun, Guo-Xin; Wu, Hui-Lan; Chu, Cheng-Cai; Ling, Hong-Qing; Rosen, Barry P.; Zhu, Yong-Guan

2011-01-01

Summary Biotransformation of arsenic includes oxidation, reduction, methylation and conversion to more complex organic arsenicals. Members of the class of arsenite [As(III)] S-adenosylmethyltransferase enzymes catalyze As(III) methylation to a variety of mono-, di- and trimethylated species, some of which are less toxic than As(III) itself. However, no methyltransferase gene has been identified in plants. Here, an arsM gene from the soil bacterium Rhodopseudomonas palustris was expressed in Japonica rice (Oryza sativa L.) cultivar Nipponbare, and the transgenic rice produced methylated arsenic species, which were measured by inductively coupled plasma mass spectrometry (ICP-MS) and high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). Both monomethylarsenate [MAs(V)] and dimethylarsenate [DMAs(V)] were detected in the root and shoot of transgenic rice. After 12-d exposure to As(III), the transgenic rice gave off 10-fold more volatile arsenicals. The present study demonstrates that expression of an arsM gene in rice induces arsenic methylation and volatilization, providing a potential stratagem for phytoremediation theoretically. PMID:21517874

A portable and inexpensive method for quantifying ambient intermediate volatility organic compounds

Science.gov (United States)

Bouvier-Brown, Nicole C.; Carrasco, Erica; Karz, James; Chang, Kylee; Nguyen, Theodore; Ruiz, Daniel; Okonta, Vivian; Gilman, Jessica B.; Kuster, William C.; de Gouw, Joost A.

2014-09-01

Volatile organic compounds (VOCs) and intermediate volatility VOCs (IVOCs) are gas-phase organic compounds which may participate in chemical reactions affecting air quality and climate. The development of an inexpensive, field-portable quantification method for higher molecular weight VOCs and IVOCs utilizing commercially available components could be used as a tool to survey aerosol precursors or identify and monitor air quality in various communities. We characterized the performance characteristics for the HayeSep-Q adsorbent with a representative selection of anthropogenic and biogenic VOC standards and optimized experimental conditions and procedures for field collections followed by laboratory analysis. All VOCs were analyzed using gas chromatography coupled with mass spectrometry. Precision (average 22%) and accuracy were reasonable and the limit of detection ranged from 10 to 80 pmol/mol (ppt) for the studied compounds. The method was employed at the Los Angeles site during the CalNex campaign in summer 2010 and ambient mixing ratios agreed well (slope 0.69-1.06, R2 0.67-0.71) with measurements made using an in-situ GC-MS - a distinctly different sampling and quantification method. This new technique can be applied to quantify ambient biogenic and anthropogenic C8-C15 VOCs and IVOCs.

The Venus flytrap attracts insects by the release of volatile organic compounds.

Science.gov (United States)

Kreuzwieser, Jürgen; Scheerer, Ursel; Kruse, Jörg; Burzlaff, Tim; Honsel, Anne; Alfarraj, Saleh; Georgiev, Plamen; Schnitzler, Jörg-Peter; Ghirardo, Andrea; Kreuzer, Ines; Hedrich, Rainer; Rennenberg, Heinz

2014-02-01

Does Dionaea muscipula, the Venus flytrap, use a particular mechanism to attract animal prey? This question was raised by Charles Darwin 140 years ago, but it remains unanswered. This study tested the hypothesis that Dionaea releases volatile organic compounds (VOCs) to allure prey insects. For this purpose, olfactory choice bioassays were performed to elucidate if Dionaea attracts Drosophila melanogaster. The VOCs emitted by the plant were further analysed by GC-MS and proton transfer reaction-mass spectrometry (PTR-MS). The bioassays documented that Drosophila was strongly attracted by the carnivorous plant. Over 60 VOCs, including terpenes, benzenoids, and aliphatics, were emitted by Dionaea, predominantly in the light. This work further tested whether attraction of animal prey is affected by the nutritional status of the plant. For this purpose, Dionaea plants were fed with insect biomass to improve plant N status. However, although such feeding altered the VOC emission pattern by reducing terpene release, the attraction of Drosophila was not affected. From these results it is concluded that Dionaea attracts insects on the basis of food smell mimicry because the scent released has strong similarity to the bouquet of fruits and plant flowers. Such a volatile blend is emitted to attract insects searching for food to visit the deadly capture organ of the Venus flytrap.

Quasiparticles and Fermi liquid behaviour in an organic metal

Science.gov (United States)

Kiss, T.; Chainani, A.; Yamamoto, H.M.; Miyazaki, T.; Akimoto, T.; Shimojima, T.; Ishizaka, K.; Watanabe, S.; Chen, C.-T.; Fukaya, A.; Kato, R.; Shin, S.

2012-01-01

Many organic metals display exotic properties such as superconductivity, spin-charge separation and so on and have been described as quasi-one-dimensional Luttinger liquids. However, a genuine Fermi liquid behaviour with quasiparticles and Fermi surfaces have not been reported to date for any organic metal. Here, we report the experimental Fermi surface and band structure of an organic metal (BEDT-TTF)3Br(pBIB) obtained using angle-resolved photoelectron spectroscopy, and show its consistency with first-principles band structure calculations. Our results reveal a quasiparticle renormalization at low energy scales (effective mass m*=1.9 me) and ω2 dependence of the imaginary part of the self energy, limited by a kink at ~50 meV arising from coupling to molecular vibrations. The study unambiguously proves that (BEDT-TTF)3Br(pBIB) is a quasi-2D organic Fermi liquid with a Fermi surface consistent with Shubnikov-de Haas results. PMID:23011143

Recent Advances in Anhydrous Solvents for CO2 Capture: Ionic Liquids, Switchable Solvents, and Nanoparticle Organic Hybrid Materials

Directory of Open Access Journals (Sweden)

YOUNGJUNE ePARK

2015-10-01

Full Text Available CO2 capture by amine scrubbing, which has a high CO2 capture capacity and a rapid reaction rate, is the most employed and investigated approach to date. There are a number of recent large-scale demonstrations including the Boundary Dam Carbon Capture Project by SaskPower in Canada that have reported successful implementations of aqueous amine solvent in CO2 capture from flue gases. The findings from these demonstrations will significantly advance the field of CO2 capture in the coming years. While the latest efforts in aqueous amine solvents are exciting and promising, there are still several drawbacks to amine-based CO2 capture solvents including high volatility and corrosiveness of the amine solutions, as well as the high parasitic energy penalty during the solvent regeneration step. Thus, in a parallel effort, alternative CO2 capture solvents, which are often anhydrous, have been developed as the third-generation CO2 capture solvents. These novel classes of liquid materials include: Ionic Liquids (ILs, CO2-triggered switchable solvents (i.e., CO2 Binding Organic Liquids (CO2BOLs, Reversible Ionic Liquids (RevILs, and Nanoparticle Organic Hybrid Materials (NOHMs. This paper provides a review of these various anhydrous solvents and their potential for CO2 capture. Particular attention is given to the mechanisms of CO2 absorption in these solvents, their regeneration and their processability – especially taking into account their viscosity. While not intended to provide a complete coverage of the existing literature, this review aims at pointing the major findings reported for these new classes of CO2 capture media.

Computation of liquid-liquid equilibria and phase stabilities: implications for RH-dependent gas/particle partitioning of organic-inorganic aerosols

Directory of Open Access Journals (Sweden)

A. Zuend

2010-08-01

Full Text Available Semivolatile organic and inorganic aerosol species partition between the gas and aerosol particle phases to maintain thermodynamic equilibrium. Liquid-liquid phase separation into an organic-rich and an aqueous electrolyte phase can occur in the aerosol as a result of the salting-out effect. Such liquid-liquid equilibria (LLE affect the gas/particle partitioning of the different semivolatile compounds and might significantly alter both particle mass and composition as compared to a one-phase particle. We present a new liquid-liquid equilibrium and gas/particle partitioning model, using as a basis the group-contribution model AIOMFAC (Zuend et al., 2008. This model allows the reliable computation of the liquid-liquid coexistence curve (binodal, corresponding tie-lines, the limit of stability/metastability (spinodal, and further thermodynamic properties of multicomponent systems. Calculations for ternary and multicomponent alcohol/polyol-water-salt mixtures suggest that LLE are a prevalent feature of organic-inorganic aerosol systems. A six-component polyol-water-ammonium sulphate system is used to simulate effects of relative humidity (RH and the presence of liquid-liquid phase separation on the gas/particle partitioning. RH, salt concentration, and hydrophilicity (water-solubility are identified as key features in defining the region of a miscibility gap and govern the extent to which compound partitioning is affected by changes in RH. The model predicts that liquid-liquid phase separation can lead to either an increase or decrease in total particulate mass, depending on the overall composition of a system and the particle water content, which is related to the hydrophilicity of the different organic and inorganic compounds. Neglecting non-ideality and liquid-liquid phase separations by assuming an ideal mixture leads to an overestimation of the total particulate mass by up to 30% for the composition and RH range considered in the six

Profiling of volatile organic compounds produced by clinical Aspergillus isolates using gas chromatography-mass spectrometry

NARCIS (Netherlands)

Gerritsen, M G; Brinkman, P; Escobar Salazar, Natalia; Bos, L D; de Heer, K; Meijer, M; Janssen, H-G; de Cock, H; Wösten, H A B; Visser, C.E.; van Oers, M H J; Sterk, P J

Volatile organic compounds (VOCs) in exhaled breath may identify the presence of invasive pulmonary aspergillosis. We aimed to detect VOC profiles emitted by in vitro cultured, clinical Aspergillus isolates using gas chromatography-mass spectrometry (GC-MS). Three clinical Aspergillus isolates and a

Profiling of volatile organic compounds produced by clinical Aspergillus isolates using gas chromatography-mass spectrometry

NARCIS (Netherlands)

Gerritsen, M. G.; Brinkman, P.; Escobar, N.; Bos, L. D.; de Heer, K.; Meijer, M.; Janssen, H.-G.; de Cock, H.; Wösten, H. A. B.; Visser, C. E.; van Oers, M. H. J.; Sterk, P. J.

2018-01-01

Volatile organic compounds (VOCs) in exhaled breath may identify the presence of invasive pulmonary aspergillosis. We aimed to detect VOC profiles emitted by in vitro cultured, clinical Aspergillus isolates using gas chromatography-mass spectrometry (GC-MS). Three clinical Aspergillus isolates and a

Development of sampling method and chromatographic analysis of volatile organic compounds emitted from human skin.

Science.gov (United States)

Grabowska-Polanowska, Beata; Miarka, Przemysław; Skowron, Monika; Sułowicz, Joanna; Wojtyna, Katarzyna; Moskal, Karolina; Śliwka, Ireneusz

2017-10-01

The studies on volatile organic compounds emitted from skin are an interest for chemists, biologists and physicians due to their role in development of different scientific areas, including medical diagnostics, forensic medicine and the perfume design. This paper presents a proposal of two sampling methods applied to skin odor collection: the first one uses a bag of cellulose film, the second one, using cellulose sachets filled with active carbon. Volatile organic compounds were adsorbed on carbon sorbent, removed via thermal desorption and analyzed using gas chromatograph with mass spectrometer. The first sampling method allowed identification of more compounds (52) comparing to the second one (30). Quantitative analyses for acetone, butanal, pentanal and hexanal were done. The skin odor sampling method using a bag of cellulose film, allowed the identification of many more compounds when compared with the method using a sachet filled with active carbon.

Metal–organic frameworks based membranes for liquid separation

KAUST Repository

Li, Xin

2017-11-07

Metal-organic frameworks (MOFs) represent a fascinating class of solid crystalline materials which can be self-assembled in a straightforward manner by the coordination of metal ions or clusters with organic ligands. Owing to their intrinsic porous characteristics, unique chemical versatility and abundant functionalities, MOFs have received substantial attention for diverse industrial applications, including membrane separation. Exciting research activities ranging from fabrication strategies to separation applications of MOF-based membranes have appeared. Inspired by the marvelous achievements of MOF-based membranes in gas separations, liquid separations are also being explored for the purpose of constructing continuous MOFs membranes or MOF-based mixed matrix membranes. Although these are in an emerging stage of vigorous development, most efforts are directed towards improving the liquid separation efficiency with well-designed MOF-based membranes. Therefore, as an increasing trend in membrane separation, the field of MOF-based membranes for liquid separation is highlighted in this review. The criteria for judicious selection of MOFs in fabricating MOF-based membranes are given. Special attention is paid to rational design strategies for MOF-based membranes, along with the latest application progress in the area of liquid separations, such as pervaporation, water treatment, and organic solvent nanofiltration. Moreover, some attractive dual-function applications of MOF-based membranes in the removal of micropollutants, degradation, and antibacterial activity are also reviewed. Finally, we define the remaining challenges and future opportunities in this field. This Tutorial Review provides an overview and outlook for MOF-based membranes for liquid separations. Further development of MOF-based membranes for liquid separation must consider the demands of strict separation standards and environmental safety for industrial application.

Metal-organic frameworks based membranes for liquid separation.

Science.gov (United States)

Li, Xin; Liu, Yuxin; Wang, Jing; Gascon, Jorge; Li, Jiansheng; Van der Bruggen, Bart

2017-11-27

Metal-organic frameworks (MOFs) represent a fascinating class of solid crystalline materials which can be self-assembled in a straightforward manner by the coordination of metal ions or clusters with organic ligands. Owing to their intrinsic porous characteristics, unique chemical versatility and abundant functionalities, MOFs have received substantial attention for diverse industrial applications, including membrane separation. Exciting research activities ranging from fabrication strategies to separation applications of MOF-based membranes have appeared. Inspired by the marvelous achievements of MOF-based membranes in gas separations, liquid separations are also being explored for the purpose of constructing continuous MOFs membranes or MOF-based mixed matrix membranes. Although these are in an emerging stage of vigorous development, most efforts are directed towards improving the liquid separation efficiency with well-designed MOF-based membranes. Therefore, as an increasing trend in membrane separation, the field of MOF-based membranes for liquid separation is highlighted in this review. The criteria for judicious selection of MOFs in fabricating MOF-based membranes are given. Special attention is paid to rational design strategies for MOF-based membranes, along with the latest application progress in the area of liquid separations, such as pervaporation, water treatment, and organic solvent nanofiltration. Moreover, some attractive dual-function applications of MOF-based membranes in the removal of micropollutants, degradation, and antibacterial activity are also reviewed. Finally, we define the remaining challenges and future opportunities in this field. This Tutorial Review provides an overview and outlook for MOF-based membranes for liquid separations. Further development of MOF-based membranes for liquid separation must consider the demands of strict separation standards and environmental safety for industrial application.

Modeling the gas-particle partitioning of secondary organic aerosol: the importance of liquid-liquid phase separation

Directory of Open Access Journals (Sweden)

A. Zuend

2012-05-01

Full Text Available The partitioning of semivolatile organic compounds between the gas phase and aerosol particles is an important source of secondary organic aerosol (SOA. Gas-particle partitioning of organic and inorganic species is influenced by the physical state and water content of aerosols, and therefore ambient relative humidity (RH, as well as temperature and organic loading levels. We introduce a novel combination of the thermodynamic models AIOMFAC (for liquid mixture non-ideality and EVAPORATION (for pure compound vapor pressures with oxidation product information from the Master Chemical Mechanism (MCM for the computation of gas-particle partitioning of organic compounds and water. The presence and impact of a liquid-liquid phase separation in the condensed phase is calculated as a function of variations in relative humidity, organic loading levels, and associated changes in aerosol composition. We show that a complex system of water, ammonium sulfate, and SOA from the ozonolysis of α-pinene exhibits liquid-liquid phase separation over a wide range of relative humidities (simulated from 30% to 99% RH. Since fully coupled phase separation and gas-particle partitioning calculations are computationally expensive, several simplified model approaches are tested with regard to computational costs and accuracy of predictions compared to the benchmark calculation. It is shown that forcing a liquid one-phase aerosol with or without consideration of non-ideal mixing bears the potential for vastly incorrect partitioning predictions. Assuming an ideal mixture leads to substantial overestimation of the particulate organic mass, by more than 100% at RH values of 80% and by more than 200% at RH values of 95%. Moreover, the simplified one-phase cases stress two key points for accurate gas-particle partitioning calculations: (1 non-ideality in the condensed phase needs to be considered and (2 liquid-liquid phase separation is a consequence of considerable deviations

Research and development of lithium isotope separation using an ionic-liquid impregnated organic membrane

International Nuclear Information System (INIS)

Hoshino, Tsuyoshi

2013-01-01

The tritium needed as a fuel for fusion reactors is produced by the neutron capture reaction of lithium-6 ( 6 Li) in tritium breeding materials. However, natural Li contains only about 7.6 at.% 6 Li. In Japan, new lithium isotope separation technique using ionic-liquid impregnated organic membranes have been developed. The improvement in the durability of the ionic-liquid impregnated organic membrane is one of the main issues for stable, long-term operation of electrodialysis cells while maintaining good performance. Therefore, we developed highly-durable ionic-liquid impregnated organic membrane. Both ends of the ionic-liquid impregnated organic membrane were covered by a nafion 324 overcoat to prevent the outflow of the ionic liquid. The transmission of Lithium aqueous solution after 10 hours under the highly-durable ionic-liquid impregnated organic membrane is almost 13%. So this highly-durable ionic-liquid impregnated organic membrane for long operating of electrodialysis cells has been developed through successful prevention of ion liquid dissolution. (J.P.N.)

Control of volatile organic compound emissions: the issues

Energy Technology Data Exchange (ETDEWEB)

Woodfield, M.; Marlowe, I.

1989-11-01

This review paper outlines the problems caused by the emissions of volatile organic compounds (VOC) which are causing increasing concern because of their part in the formation of photochemical oxidation that causes damage to crops and vegetation and because of the toxic and climatic effects. It briefly summarises current knowledge of VOC emissions and their effects and then suggests options for abatement of VOC emissions in the UK and the EEC. A comparison of anthropogenic VOC emission in the UK and the EEC from various sources is given. Further information is needed on current emissions, on the costs and efficiencies of control technologies and on the effects of control on industry before decisions can be made on the suitability, extent and strategy to control VOC emissions in the UK. The report was prepared for the UK Department of Trade and Industry (Headquarters).

Gas-shell-encapsulation of activated carbon to reduce fouling and increase the efficacy of volatile organic compound removal

NARCIS (Netherlands)

Poortinga, A.T.; van Rijn, C.J.M.

2017-01-01

A method to encapsulate activated carbon particles is presented that reduces fouling of these particles with Natural Organic Matter (NOM) to preserve their adsorption capacity for Volatile Organic Compounds (VOCs) from water in the presence of NOM. The encapsulation method uses an oil-in-water

Manure application and ammonia volatilization

NARCIS (Netherlands)

Huijsmans, J.F.M.

2003-01-01

Keywords: manure application, ammonia volatilization, environmental conditions, application technique, incorporation technique, draught force, work organization, costs Livestock manure applied on farmland is an important source of ammonia (NH3) volatilization, and NH3 is a major atmospheric

Adolescent Exposure to Toxic Volatile Organic Chemicals From E-Cigarettes.

Science.gov (United States)

Rubinstein, Mark L; Delucchi, Kevin; Benowitz, Neal L; Ramo, Danielle E

2018-04-01

There is an urgent need to understand the safety of e-cigarettes with adolescents. We sought to identify the presence of chemical toxicants associated with e-cigarette use among adolescents. Adolescent e-cigarette users (≥1 use within the past 30 days, ≥10 lifetime e-cigarette use episodes) were divided into e-cigarette-only users (no cigarettes in the past 30 days, urine 4-[methylnitrosamino]-1-[3-pyridyl]-1-butanol [NNAL] level 30 pg/mL; n = 16), and never-using controls ( N = 20). Saliva was collected within 24 hours of the last e-cigarette use for analysis of cotinine and urine for analysis of NNAL and levels of 8 volatile organic chemical compounds. Bivariate analyses compared e-cigarette-only users with dual users, and regression analyses compared e-cigarette-only users with dual users and controls on levels of toxicants. The participants were 16.4 years old on average. Urine excretion of metabolites of benzene, ethylene oxide, acrylonitrile, acrolein, and acrylamide was significantly higher in dual users versus e-cigarette-only users (all P < .05). Excretion of metabolites of acrylonitrile, acrolein, propylene oxide, acrylamide, and crotonaldehyde were significantly higher in e-cigarette-only users compared with controls (all P < .05). Although e-cigarette vapor may be less hazardous than tobacco smoke, our findings can be used to challenge the idea that e-cigarette vapor is safe, because many of the volatile organic compounds we identified are carcinogenic. Messaging to teenagers should include warnings about the potential risk from toxic exposure to carcinogenic compounds generated by these products. Copyright © 2018 by the American Academy of Pediatrics.

Empirical Analysis of Stochastic Volatility Model by Hybrid Monte Carlo Algorithm

International Nuclear Information System (INIS)

Takaishi, Tetsuya

2013-01-01

The stochastic volatility model is one of volatility models which infer latent volatility of asset returns. The Bayesian inference of the stochastic volatility (SV) model is performed by the hybrid Monte Carlo (HMC) algorithm which is superior to other Markov Chain Monte Carlo methods in sampling volatility variables. We perform the HMC simulations of the SV model for two liquid stock returns traded on the Tokyo Stock Exchange and measure the volatilities of those stock returns. Then we calculate the accuracy of the volatility measurement using the realized volatility as a proxy of the true volatility and compare the SV model with the GARCH model which is one of other volatility models. Using the accuracy calculated with the realized volatility we find that empirically the SV model performs better than the GARCH model.

Analysis of volatile organic compound from Elaeis guineensis inflorescences planted on different soil types in Malaysia

Science.gov (United States)

Muhamad Fahmi, M. H.; Ahmad Bukhary, A. K.; Norma, H.; Idris, A. B.

2016-11-01

The main attractant compound for Eleidobius kamerunicus to male spikelet Elaeis guineensis (oil palm) were determined by analyzing volatile organic compound extracted from E. guineenses inflorescences planted on different soil types namely peat soil, clay soil and sandy soil. Anthesizing male oil palm inflorescences were randomly choosen from palm aged between 4-5 years old age. Extraction of the volatiles from the oil palm inflorescences were performed by Accelerated Solvent Extraction method (ASE). The extracted volatile compound were determined by using gas chromatography-mass spectrometry. Out of ten identified compound, estragole was found to be a major compound in sandy soil (37.49%), clay soil (30.71%) and peat soil (27.79%). Other compound such as 9,12-octadecadieonic acid and n-hexadecanoic acid were found as major compound in peat soil (27.18%) and (7.45%); sandy soil (14.15 %) and (9.31%); and clay soil (30.23%) and (4.99%). This study shows that estragole was the predominant volatile compound detected in oil palm inflorescences with highly concentrated in palm planted in sandy soil type.

WORKSHOP REPORT - CONSIDERATIONS FOR DEVELOPING LEACHING TEST METHODS FOR SEMI- AND NON-VOLATILE ORGANIC COMPOUNDS

Science.gov (United States)

The report provides a summary of the information exchange at a workshop on the potential for release of semi- or non-volatile organic constituents at contaminated sites where sub-surface treatment has been used to control migration, and from waste that is disposed or re-used. The...

Sensory and Physiological Effects on Humans of Combined Exposures to Air Temperatures and Volatile Organic Compounds

DEFF Research Database (Denmark)

Mølhave, Lars; Liu, Zunyong; Jørgensen, Anne Hempel

1993-01-01

Ten healthy humans were exposed to combinations of volatile organic compounds (VOCs) and air temperature (0 mg/m3 and 10 mg/m3 of a mixture of 22 volatile organic compounds and 18, 22 and 26° C). Previously demonstrated effects of VOCs and thermal exposures were replicated. For the first time nasal...... cross-sectional areas and nasal volumes, as measured by acoustic rhinometry, were shown to decrease with decreasing temperature and increasing VOC exposure. Temperature and pollutant exposures affected air quality, the need for more ventilation, skin humidity on the forehead, sweating, acute sensory...... irritation and possibly watering eyes in an additive way. Interactions were found for odor intensity (p = 0.1), perceived facial skin temperature and dryness, general well-being, tear film stability, and nasal cavity dimension. The presence of interactions implies that in the future guidelines for acceptable...

Proficiency Test SYKE 8/2012. Volatile organic compounds in water and soil

OpenAIRE

Korhonen-Ylönen, Kaija; Nuutinen, Jari; Leivuori, Mirja; Ilmakunnas, Markku

2013-01-01

Proftest SYKE carried out the proficiency test for analysis of volatile organic compounds from water and soil in October 2012. One artificial sample and one river water sample and one soil sample were distributed. In total, 15 laboratories participated in the proficiency test. Either the calculated concentration or the robust mean value was chosen to be the assigned value for the measurement. The performance of the participants was evaluated by using z scores. In this proficiency test 72 % of...

[Photoionization ion mobility spectrometry (UV-IMS) for the isomeric volatile organic compounds].

Science.gov (United States)

Li, Hu; Niu, Wen-qi; Wang, Hong-mei; Huang, Chao-qun; Jiang, Hai-he; Chu, Yan-nan

2012-01-01

The construction and performance study is reported for a newly developed ultraviolet photoionization ion mobility spectrometry (UV-IMS). In the present paper, an UV-IMS technique was firstly developed to detect eleven isomeric volatile organic compounds including the differences in the structure of carbon chain, the style of function group and the position of function group. Their reduced mobility values were determined and increased in this order: linears alcohols homemade UV-IMS was around ppb-ppm.

Electron beam treatment of toxic volatile organic compounds and dioxins

International Nuclear Information System (INIS)

Kojima, Takuji

2006-01-01

Considerations of wastes based on the reduction, reuse and recycle in daily life are primary measures to conserve our environment, but the control technology is necessary to support these measures. The electron beam (EB) process is promising as an advanced purification process having advantages such as a quick treatment of big volume gas, applicability even for very low concentration pollutants as the further purification at the downstream of existing process, and decomposition of pollutants into non-toxic substances by one process. The EB technology has been developed for treatment of toxic volatile organic compounds (VOCs) in ventilation gas and dioxins in solid waste incineration flue gas. (author)

Volatile organic compound (VOC) emissions during malting and beer manufacture

Science.gov (United States)

Gibson, Nigel B.; Costigan, Gavin T.; Swannell, Richard P. J.; Woodfield, Michael J.

Estimates have been made of the amounts of volatile organic compounds (VOCs) released during different stages of beer manufacture. The estimates are based on recent measurements and plant specification data supplied by manufacturers. Data were obtained for three main manufacturing processes (malting, wort processing and fermentation) for three commercial beer types. Some data on the speciation of emitted compounds have been obtained. Based on these measurements, an estimate of the total unabated VOC emission. from the U.K. brewing industry was calculated as 3.5 kta -1, over 95% of which was generated during barley malting. This value does not include any correction for air pollution control.

Stability of volatile organics in environmental soil samples. Final report

Energy Technology Data Exchange (ETDEWEB)

Maskarinec, M.P.; Bayne, C.K.; Jenkins, R.A.; Johnson, L.H.; Holladay, S.K.

1992-11-01

This report focuses on data generated for the purpose of establishing the stability of 19 volatile organic compounds in environmental soil samples. The study was carried out over a 56 day (for two soils) and a 111 day (for one reference soil) time frame and took into account as many variables as possible within the constraints of budget and time. The objectives of the study were: 1) to provide a data base which could be used to provide guidance on pre-analytical holding times for regulatory purposes; and 2) to provide a basis for the evaluation of data which is generated outside of the currently allowable holding times.

Gas-shell-encapsulation of Activated Carbon to Reduce Fouling and Increase the Efficacy of Volatile Organic Compound Removal

NARCIS (Netherlands)

Poortinga, Albert T.; Rijn, van Cees J.M.

2017-01-01

A method to encapsulate activated carbon particles is presented that reduces fouling of these particles with Natural Organic Matter (NOM) to preserve their adsorption capacity for Volatile Organic Compounds (VOCs) from water in the presence of NOM. The encapsulation method uses an oil-in-water

Liquid biofuel production from volatile fatty acids

Energy Technology Data Exchange (ETDEWEB)

Steinbusch, K.J.J.

2010-03-19

The production of renewable fuels and chemicals reduces the dependency on fossil fuels and limits the increase of CO2 concentration in the atmosphere only if a sustainable feedstock and an energy efficient process are used. The thesis assesses the possibility to use municipal and industrial waste as biomass feedstock to have little of no competition with food production, and to save greenhouse gasses emissions. Waste is a complex substrate with a diverse composition and high water content. It can be homogenized without losing its initial energy value by anaerobic conversion to volatile fatty acids (VFA). Using VFA gives the opportunity to process cheap and abundantly present biomass residues to a fuel and chemical instead of sugar containing crops or vegetable oil. This thesis describes the feasibility to convert VFA to compounds with a higher energy content using mixed culture fermentations by eliminating of oxygen and/or increasing the carbon and hydrogen content. At high hydrogen pressure, protons and electrons release via the reduction of organic products such as VFA becomes thermodynamically more attractive. Three VFA reduction reactions were studied: hydrogenation to an alcohol with (1) hydrogen and (2) an electrode as electron donor, and (3) by chain elongation with hydrogen and ethanol. Based on concentration, production rate and efficiency, elongation of acetate with hydrogen and/or ethanol was the best technique to convert VFA into a fuel. In a CSTR (Continuous-flow stirred-tank reactor), 10.5 g L{sup -1} caproic acid and 0.48 g L{sup -1} caprylic acid were produced with ethanol and/or hydrogen at a specific MCFA (medium-chain fatty acids) production activity of 2.9 g caproate and 0.09 g caprylate per gram VSS d{sup -1} (volatile suspended solids). The products were selectively removed by calcium precipitation and solvent extraction with ethyl hexanoate and petroleum ether. Microbial characterization revealed that the microbial populations were stable and

Recent Advances in Anhydrous Solvents for CO{sub 2} Capture: Ionic Liquids, Switchable Solvents, and Nanoparticle Organic Hybrid Materials

Energy Technology Data Exchange (ETDEWEB)

Park, Youngjune [School of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju (Korea, Republic of); Lin, Kun-Yi Andrew [Department of Environmental Engineering, National Chung Hsing University, Taichung City (China); Park, Ah-Hyung Alissa, E-mail: ap2622@columbia.edu [Department of Earth and Environmental Engineering, Lenfest Center for Sustainable Energy, Columbia University, New York, NY (United States); Department of Chemical Engineering, Lenfest Center for Sustainable Energy, Columbia University, New York, NY (United States); Petit, Camille, E-mail: ap2622@columbia.edu [Department of Chemical Engineering, Imperial College London, London (United Kingdom)

2015-10-01

CO{sub 2} capture by amine scrubbing, which has a high CO{sub 2} capture capacity and a rapid reaction rate, is the most employed and investigated approach to date. There are a number of recent large-scale demonstrations including the Boundary Dam Carbon Capture Project by SaskPower in Canada that have reported successful implementations of aqueous amine solvent in CO{sub 2} capture from flue gases. The findings from these demonstrations will significantly advance the field of CO{sub 2} capture in the coming years. While the latest efforts in aqueous amine solvents are exciting and promising, there are still several drawbacks to amine-based CO{sub 2} capture solvents including high volatility and corrosiveness of the amine solutions as well as the high parasitic energy penalty during the solvent regeneration step. Thus, in a parallel effort, alternative CO{sub 2} capture solvents, which are often anhydrous, have been developed as the third-generation CO{sub 2} capture solvents. These novel classes of liquid materials include ionic liquids, CO{sub 2}-triggered switchable solvents (i.e., CO{sub 2}-binding organic liquids, reversible ionic liquids), and nanoparticle organic hybrid materials. This paper provides a review of these various anhydrous solvents and their potential for CO{sub 2} capture. Particular attention is given to the mechanisms of CO{sub 2} absorption in these solvents, their regeneration and their processability – especially taking into account their viscosity. While not intended to provide a complete coverage of the existing literature, this review aims at pointing the major findings reported for these new classes of CO{sub 2} capture media.

40 CFR 60.502 - Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline terminals.

Science.gov (United States)

2010-07-01

... (VOC) emissions from bulk gasoline terminals. 60.502 Section 60.502 Protection of Environment... SOURCES Standards of Performance for Bulk Gasoline Terminals § 60.502 Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline terminals. On and after the date on which § 60.8(a) requires a...

Designing Kitaev Spin Liquids in Metal-Organic Frameworks

Science.gov (United States)

Yamada, Masahiko G.; Fujita, Hiroyuki; Oshikawa, Masaki

2017-08-01

Kitaev's honeycomb lattice spin model is a remarkable exactly solvable model, which has a particular type of spin liquid (Kitaev spin liquid) as the ground state. Although its possible realization in iridates and α -RuCl3 has been vigorously discussed recently, these materials have substantial non-Kitaev direct exchange interactions and do not have a spin liquid ground state. We propose metal-organic frameworks (MOFs) with Ru3 + (or Os3 + ), forming the honeycomb lattice as promising candidates for a more ideal realization of Kitaev-type spin models, where the direct exchange interaction is strongly suppressed. The great flexibility of MOFs allows generalization to other three-dimensional lattices for the potential realization of a variety of spin liquids, such as a Weyl spin liquid.

Microscopic properties of ionic liquid/organic semiconductor interfaces revealed by molecular dynamics simulations.

Science.gov (United States)

Yokota, Yasuyuki; Miyamoto, Hiroo; Imanishi, Akihito; Takeya, Jun; Inagaki, Kouji; Morikawa, Yoshitada; Fukui, Ken-Ichi

2018-05-09

Electric double-layer transistors based on ionic liquid/organic semiconductor interfaces have been extensively studied during the past decade because of their high carrier densities at low operation voltages. Microscopic structures and the dynamics of ionic liquids likely determine the device performance; however, knowledge of these is limited by a lack of appropriate experimental tools. In this study, we investigated ionic liquid/organic semiconductor interfaces using molecular dynamics to reveal the microscopic properties of ionic liquids. The organic semiconductors include pentacene, rubrene, fullerene, and 7,7,8,8-tetracyanoquinodimethane (TCNQ). While ionic liquids close to the substrate always form the specific layered structures, the surface properties of organic semiconductors drastically alter the ionic dynamics. Ionic liquids at the fullerene interface behave as a two-dimensional ionic crystal because of the energy gain derived from the favorable electrostatic interaction on the corrugated periodic substrate.

Organic non-volatile memories from ferroelectric phase separated blends

Science.gov (United States)

Asadi, Kamal; de Leeuw, Dago; de Boer, Bert; Blom, Paul

2009-03-01

Ferroelectric polarisation is an attractive physical property for non-volatile binary switching. The functionality of the targeted memory should be based on resistive switching. Conductivity and ferroelectricity however cannot be tuned independently. The challenge is to develop a storage medium in which the favourable properties of ferroelectrics such as bistability and non-volatility can be combined with the beneficial properties provided by semiconductors such as conductivity and rectification. In this contribution we present an integrated solution by blending semiconducting and ferroelectric polymers into phase separated networks. The polarisation field of the ferroelectric modulates the injection barrier at the semiconductor--metal contact. This combination allows for solution-processed non-volatile memory arrays with a simple cross-bar architecture that can be read-out non-destructively. Based on this general concept a non-volatile, reversible switchable Schottky diode with relatively fast programming time of shorter than 100 microseconds, long information retention time of longer than 10^ days, and high programming cycle endurance with non-destructive read-out is demonstrated.

Formation of organic aerosol in the Paris region during the MEGAPOLI summer campaign: evaluation of the volatility-basis-set approach within the CHIMERE model

Directory of Open Access Journals (Sweden)

Q. J. Zhang

2013-06-01

Full Text Available Simulations with the chemistry transport model CHIMERE are compared to measurements performed during the MEGAPOLI (Megacities: Emissions, urban, regional and Global Atmospheric POLlution and climate effects, and Integrated tools for assessment and mitigation summer campaign in the Greater Paris region in July 2009. The volatility-basis-set approach (VBS is implemented into this model, taking into account the volatility of primary organic aerosol (POA and the chemical aging of semi-volatile organic species. Organic aerosol is the main focus and is simulated with three different configurations with a modified treatment of POA volatility and modified secondary organic aerosol (SOA formation schemes. In addition, two types of emission inventories are used as model input in order to test the uncertainty related to the emissions. Predictions of basic meteorological parameters and primary and secondary pollutant concentrations are evaluated, and four pollution regimes are defined according to the air mass origin. Primary pollutants are generally overestimated, while ozone is consistent with observations. Sulfate is generally overestimated, while ammonium and nitrate levels are well simulated with the refined emission data set. As expected, the simulation with non-volatile POA and a single-step SOA formation mechanism largely overestimates POA and underestimates SOA. Simulation of organic aerosol with the VBS approach taking into account the aging of semi-volatile organic compounds (SVOC shows the best correlation with measurements. High-concentration events observed mostly after long-range transport are well reproduced by the model. Depending on the emission inventory used, simulated POA levels are either reasonable or underestimated, while SOA levels tend to be overestimated. Several uncertainties related to the VBS scheme (POA volatility, SOA yields, the aging parameterization, to emission input data, and to simulated OH levels can be responsible for

Biogenic volatile organic compound emissions from vegetation fires.

Science.gov (United States)

Ciccioli, Paolo; Centritto, Mauro; Loreto, Francesco

2014-08-01

The aim of this paper was to provide an overview of the current state of the art on research into the emission of biogenic volatile organic compounds (BVOCs) from vegetation fires. Significant amounts of VOCs are emitted from vegetation fires, including several reactive compounds, the majority belonging to the isoprenoid family, which rapidly disappear in the plume to yield pollutants such as secondary organic aerosol and ozone. This makes determination of fire-induced BVOC emission difficult, particularly in areas where the ratio between VOCs and anthropogenic NOx is favourable to the production of ozone, such as Mediterranean areas and highly anthropic temperate (and fire-prone) regions of the Earth. Fire emissions affecting relatively pristine areas, such as the Amazon and the African savannah, are representative of emissions of undisturbed plant communities. We also examined expected BVOC emissions at different stages of fire development and combustion, from drying to flaming, and from heatwaves coming into contact with unburned vegetation at the edge of fires. We conclude that forest fires may dramatically change emission factors and the profile of emitted BVOCs, thereby influencing the chemistry and physics of the atmosphere, the physiology of plants and the evolution of plant communities within the ecosystem. © 2014 The Authors. Plant, Cell & Environment published by John Wiley & Sons Ltd.

Investigation of the Extinguishing Features for Liquid Fuels and Organic Flammable Liquids Atomized by a Water Flow

Directory of Open Access Journals (Sweden)

Voytkov Ivan V.

2016-01-01

Full Text Available The processes of heat and mass transfer were investigated experimentally while moving and evaporating the atomized water flow in high-temperature combustion products of typical liquid fuels and organic flammable liquids: gasoline, kerosene, acetone, crude oil, industrial alcohol. We determined typical periods of liquid extinguishing by an atomized water flow of various dispersability. Data of the discharge of extinguishing medium corresponding to various parameters of atomization and duration of using the atomization devices was presented. It is shown that Um≈3.5 m/s is a minimal outflow velocity of droplets during moving while passing the distance of 1m in the high-temperature gas medium to stop the combustion of organic liquids.

Source apportionment of ambient volatile organic compounds in the Pearl River Delta, China: Part II

Science.gov (United States)

Liu, Ying; Shao, Min; Lu, Sihua; Chang, Chih-Chung; Wang, Jia-Lin; Fu, Linlin

The chemical mass balance receptor model was applied to the source apportionment of 58 hydrocarbons measured at seven sites in a field campaign that examined regional air quality in the Pearl River Delta (PRD) region in the fall of 2004. A total of 12 volatile organic compound (VOC) emission sources were considered, including gasoline- and diesel-powered vehicle exhausts, headspace vapors of gasoline and diesel fuel, vehicle evaporative emissions, liquid petroleum gas (LPG) leakage, paint vapors, asphalt emissions from paved roads, biomass combustion, coal combustion, the chemical industry, and petroleum refineries. Vehicle exhaust was the largest source of VOCs, contributing to >50% of ambient VOCs at the three urban sites (Guangzhou, Foshan, and Zhongshan). LPG leakage played an important role, representing 8-16% of emissions at most sites in the PRD. Solvent usage was the biggest emitter of VOCs at Dongguan, an industrial site, contributing 33% of ambient VOCs. Similarly, at Xinken, a non-urban site, the evaporation of solvents and coatings was the largest emission source, accounting for 31% of emissions, probably because it was downwind of Dongguan. Local biomass combustion was a noticeable source of VOCs at Xinken; although its contribution was estimated at 14.3%, biomass combustion was the third largest VOC source at this site.

Volatile organic compound emmission rates from mixed deciduous and coniferous foest in Northern Wisconsin, USA

Science.gov (United States)

J. G. Isebrands; A. B. Guenther; P. Harley; D. Helmig; L. Klinger; L. Vierling; P. Zimmerman; C. Geron

1999-01-01

Biogenic emissions of volatile organic compounds {VOC) from forests play an important role in regulating the atmospheric trace gas composition including global tropospheric ozone concentrations. However, more information is needed on VOC emission rates from different forest regions of the world to understand regional and global impacts and to implement possible...

The Influence Of Mass Fraction Of Dressed Coal On Ignition Conditions Of Composite Liquid Fuel Droplet

Directory of Open Access Journals (Sweden)

Shlegel Nikita E.

2015-01-01

Full Text Available The laws of condition modification of inert heat and ignition in an oxidant flow of composite liquid fuel droplet were studied by the developed experimental setup. Investigations were for composite liquid fuel composition based on the waste of bituminous and nonbaking coal processing, appropriate carbon dust, water, used motor oil. The characteristics of boundary layer inertia heat of composite liquid fuel droplet, thermal decomposition of coal organic part, the yield of volatiles and evaporation of liquid combustion component, ignition of the gas mixture and coke residue were defined.

Variation in pH of Model Secondary Organic Aerosol during Liquid-Liquid Phase Separation.

Science.gov (United States)

Dallemagne, Magda A; Huang, Xiau Ya; Eddingsaas, Nathan C

2016-05-12

The majority of atmospheric aerosols consist of both organic and inorganic components. At intermediate relative humidity (RH), atmospheric aerosol can undergo liquid-liquid phase separation (LLPS) in which the organic and inorganic fractions segregate from each other. We have extended the study of LLPS to the effect that phase separation has on the pH of the overall aerosols and the pH of the individual phases. Using confocal microscopy and pH sensitive dyes, the pH of internally mixed model aerosols consisting of polyethylene glycol 400 and ammonium sulfate as well as the pH of the organic fraction during LLPS have been directly measured. During LLPS, the pH of the organic fraction was observed to increase to 4.2 ± 0.2 from 3.8 ± 0.1 under high RH when the aerosol was internally mixed. In addition, the high spatial resolution of the confocal microscope allowed us to characterize the composition of each of the phases, and we have observed that during LLPS the organic shell still contains large quantities of water and should be characterized as an aqueous organic-rich phase rather than simply an organic phase.

Volatile organic components in the Skylab 4 spacecraft atmosphere

Science.gov (United States)

Liebich, H. M.; Bertsch, W.; Zlatkis, A.; Schneider, H. J.

1975-01-01

The volatile organic components in the spacecraft cabin atmosphere of Skylab 4 were trapped on a solid adsorbent at various times during the mission. In post-flight analyses, more than 300 compounds in concentrations from less than 1 ppb up to 8000 ppb could be detected by high-resolution gas chromatography. In the samples of the 11th, 47th, and 77th day of the mission, approximately 100 components in the molecular weight range from 58 to 592 were identified by mass spectrometry. Besides components known from other environments, such as alkanes, alkenes, and alkylated aromatic hydrocarbons, components typical of the human metabolism, such as ketones and alcohols, were found. Other typical components in the spacecraft atmosphere included fluorocarbons and various silicone compounds, mostly normal and cyclic methylsiloxanes.

Isolation and quantification of volatiles in fish by dynamic headspace sampling and mass spectrometry

DEFF Research Database (Denmark)

Refsgaard, Hanne; Haahr, Anne-Mette; Jensen, Benny

1999-01-01

A dynamic headspace sampling method for isolation of volatiles in fish has been developed. The sample preparation involved freezing of fish tissue in liquid nitrogen, pulverizing the tissue, and sampling of volatiles from an aqueous slurry of the fish powder. Similar volatile patterns were...

Micro- and Nanostructured Metal Oxide Chemical Sensors for Volatile Organic Compounds

Science.gov (United States)

Alim, M. A.; Penn, B. G.; Currie, J. R., Jr.; Batra, A. K.; Aggarwal, M. D.

2008-01-01

Aeronautic and space applications warrant the development of chemical sensors which operate in a variety of environments. This technical memorandum incorporates various kinds of chemical sensors and ways to improve their performance. The results of exploratory investigation of the binary composite polycrystalline thick-films such as SnO2-WO3, SnO2-In2O3, SnO2-ZnO for the detection of volatile organic compound (isopropanol) are reported. A short review of the present status of the new types of nanostructured sensors such as nanobelts, nanorods, nanotube, etc. based on metal oxides is presented.

The Atmospheric Oxidation of Volatile Organic Compounds Through Hydrogen Shift Reactions

DEFF Research Database (Denmark)

Knap, Hasse Christian

a radical is denoted as a H-shift reaction. Quantum chemical calculations were carried out to investigate the potential energy surface of the H-shift reactions and the subsequent decomposition pathways. The transition state theory including the Eckart quantum tunneling correction have been used to calculate...... the reaction rate constants of the H-shift reactions. The autoxidation of volatile organic compounds is an important oxidation mechanism that produces secondary organic aerosols (SOA) and recycles hydroxyl (OH) radicals. The autoxidation cycle produces a second generation peroxy radical (OOQOOH) through...... a series of H-shift reactions and O2 attachments. I have investigated the H-shift reactions in two OOQOOH radicals (hydroperoxy peroxy radicals and hydroperoxy acyl peroxy radicals). The H-shift reaction rate constants have been compared with the bimolecular reaction rate constants of the peroxy radicals...

Volatile compounds emission and health risk assessment during composting of organic fraction of municipal solid waste

DEFF Research Database (Denmark)

Mustafa, Muhammad Farooq; Liu, Yanjun; Duan, Zhenhan

2017-01-01

Degradation of mechanically sorted organic fraction (MSOF) of municipal solid waste in composting facilities is among the major contributors of volatile compounds (VCs) generation and emission, causes nuisance problems and health risks on site as well as in the vicinages. The aim of current study...

Proton transfer reaction-mass spectrometry volatile organic compound fingerprinting for monovarietal extra virgin olive oil identification

NARCIS (Netherlands)

Ruiz-Samblas, C.; Tres, A.; Koot, A.H.; Ruth, van S.M.; Gonzalez-Casado, A.; Cuadros-Rodriguez, L.

2012-01-01

Proton transfer reaction-mass spectrometry (PTR-MS) is a relatively new technique that allows the fast and accurate qualification of the volatile organic compound (VOC) fingerprint. This paper describes the analysis of thirty samples of extra virgin olive oil, of five different varieties of olive

ISOTOPIC (14C) AND CHEMICAL COMPOSITION OF ATMOSPHERIC VOLATILE ORGANIC COMPOUND FRACTIONS - PRECURSORS TO OZONE FORMATION

Science.gov (United States)

Atmospheric volatile organic compounds (VOCs) are an important factor in the production of ozone near ground level [3]. Many hydrocarbons originate from auto exhaust. However, a number of VOCs, e.g., isoprene, are known to be natural in origin. To develop reliable models for un...

Development of analytical model for condensation of vapor mixture of nitric acid and water affected volatilized ruthenium behavior in accident of evaporation to dryness by boiling of reprocessed high level liquid waste at fuel reprocessing facilities

International Nuclear Information System (INIS)

Yoshida, Kazuo

2016-08-01

An accident of evaporation to dryness by boiling of high level liquid waste is postulated as one of the severe accidents caused by the loss of cooling function at a fuel reprocessing plant. In this case, continuous vaporing of nitric acid and water leads to increase Ru volatilization in liquid waste temperature over 120degC at later boiling and dry out phases. It has been observed at the experiments with actual and synthetic liquid waste that some amount of Ru volatilizes and transfers into condensed nitric acid solution at those phases. The nitric acid and water vapor flowing from waste tank are expected to condense at compartments of actual facilities building. The volatilized Ru could transfer into condensed liquid. It is key issues for quantifying the amount of transferred Ru through the facility building to simulate these thermodynamic and chemical behaviors. An analytical model has been proposed in this report based on the condensation mechanisms of nitric acid and water in vapor-liquid equilibria. It has been also carried out for the proposed model being feasible to formulate the activity coefficients and to review the thermodynamic properties of nitric acid solution. Practicability of the proposed analytical model has been shown successfully through the feasibility study with simulation of an experiment result. (author)

Volatilization and trapping of ruthenium in high temperature processes

International Nuclear Information System (INIS)

Klein, M.; Weyers, C.; Goossens, W.R.A.

1983-01-01

This experimental study has indicated the importance of moisture and NO/sub x/ vapors on the volatility and trapping conditions of ruthenium in high temperature processes. Also the process operating conditions have a great influence on the ruthenium behavior in the off-gas purification units. Of particular interest is the observation that the ruthenium release during direct vitrification of simulated high-level liquid waste is a factor of about 5 smaller than the ruthenium release during calcination of this type of waste. Moreover, in the direct vitrification case the ruthenium escapes mostly in the form of an aerosol whereas in the calcination case a volatile ruthenium compound is dominating. Consequently, a specific ruthenium filter is not needed in the off-gas line of a direct vitrifier simplifying in this way the number of units in this off-gas line and avoiding the handling and controlling problems of such a ruthenium filter. In the future, a similar program will be started on the volatility of cesium and antimony in a liquid fed melter and on the technical reliability of the liquid fed melter and its associated gas purification units on a semi-pilote scale under simulated conditions

Extended Research on Detection of Deception Using Volatile Organic Compound (VOC) Emissions

Energy Technology Data Exchange (ETDEWEB)

Center for Human Reliability Studies

2006-06-01

A system that captures and analyzes volatile organic compound (VOC) emissions from skin surfaces may offer a viable alternative method to the polygraph instrument currently in use for detecting deception in U.S. government settings. Like the involuntary autonomic central nervous system response data gathered during polygraph testing, VOC emissions from the skin may provide data that can be used to detect stress caused by deception. Detecting VOCs, then, may present a noninvasive, non-intrusive method for observing, recording, and quantifying evidence of stress or emotional change.

Ionic Liquids: An Environmentally Friendly Media for Nucleophilic Substitution Reactions

International Nuclear Information System (INIS)

Jorapur, Yogesh R.; Chi, Dae Yoon

2006-01-01

Ionic liquids are alternative reaction media of increasing interest and are regarded as an eco-friendly alternatives, of potential use in place of the volatile organic solvents typically used in current chemical processing methods. They are emerging as the smart and excellent solvents, which are made of positive and negative ions that they are liquids near room temperature. The nucleophilic substitution reaction is one of the important method for inserting functional groups into a carbon skeleton. Many nucleophilic substitution reactions have been found with enhanced reactivity and selectivity in ionic liquid. In this review, some recent interesting results of nucleophilic substitution reactions such as hydroxylations, ether cleavages, carbon-X (X = carbon, oxygen, nitrogen, fluorine) bond forming reactions, and ring opening of epoxides in ionic liquids are discussed

Discharge characteristics of an ablative pulsed plasma thruster with non-volatile liquid propellant

Science.gov (United States)

Ling, William Yeong Liang; Schönherr, Tony; Koizumi, Hiroyuki

2017-07-01

Pulsed plasma thrusters (PPTs) are a form of electric spacecraft propulsion. They have an extremely simple structure and are highly suitable for nano/micro-spacecraft with weights in the kilogram range. Such small spacecraft have recently experienced increased growth but still lack suitable efficient propulsion systems. PPTs operate in a pulsed mode (one discharge = one shot) and typically use solid polytetrafluoroethylene (PTFE) as a propellant. However, new non-volatile liquids in the perfluoropolyether (PFPE) family have recently been found to be promising alternatives. A recent study presented results on the physical characteristics of PFPE vs. PTFE, showing that PFPE is superior in terms of physical characteristics such as its resistance to carbon deposition. This letter will examine the electrical discharge characteristics of PFPE vs. PTFE. The results demonstrate that PFPE has excellent shot-to-shot repeatability and a lower discharge resistance when compared with PTFE. Taken together with its physical characteristics, PFPE appears to be a strong contender to PTFE as a PPT propellant.

Five Years of Analyses of Volatiles, Isotopes and Organics in Gale Crater Materials

Science.gov (United States)

McAdam, A.; Mahaffy, P. R.; Andrejkovicova, S. C.; Archer, P. D., Jr.; Atreya, S. K.; Buch, A.; Coll, P. J.; Conrad, P. G.; Eigenbrode, J. L.; Farley, K. A.; Flesch, G.; Franz, H. B.; Freissinet, C.; Glavin, D. P.; Hogancamp, J. V.; House, C. H.; Knudson, C. A.; Lewis, J. M.; Malespin, C.; Martin, P. M.; Millan, M.; Ming, D. W.; Morris, R. V.; Navarro-Gonzalez, R.; Steele, A.; Stern, J. C.; Summons, R. E.; Sutter, B.; Szopa, C.; Teinturier, S.; Trainer, M. G.; Webster, C. R.; Wong, G. M.

2017-12-01

Over the last five years, the Curiosity rover has explored a variety of fluvial, lacustrine and aeolian sedimentary rocks, and soils. The Sample Analysis at Mars (SAM) instrument has analysed 3 soil and 12 rock samples, which exhibit significant chemical and mineralogical diversity in over 200 meters of vertical section. Here we will highlight several key insights enabled by recent measurements of the chemical and isotopic composition of inorganic volatiles and organic compounds detected in Gale Crater materials. Until recently samples have evolved O2 during SAM evolved gas analyses (EGA), attributed to the thermal decomposition of oxychlorine phases. A lack of O2 evolution from recent mudstone samples may indicate a difference in the composition of depositional or diagenetic fluids, and can also have implications for the detection of organic compounds since O2 can combust organics to CO2 in the SAM ovens. Recent mudstone samples have also shown little or no evolution of NO attributable to nitrate salts, possibly also as a result of changes in the chemical composition of fluids [1]. Measurements of the isotopic composition of sulfur, hydrogen, nitrogen, chlorine, and carbon in methane evolved during SAM pyrolysis are providing constraints on the conditions of possible paleoenvironments [e.g., 2, 3]. There is evidence of organic C from both EGA and GCMS measurements of Gale samples [e.g., 4, 5]. Organic sulfur volatiles have been detected in several samples, and the first opportunistic derivatization experiment produced a rich dataset indicating the presence of several organic compounds [6, 7]. A K-Ar age has been obtained from the Mojave mudstone, and the age of secondary materials formed by aqueous alteration is likely history and habitability. [1] Sutter et al. (2017) LPSC 3009. [2] Franz et al., this mtg. [3] Stern et al., this mtg. [4] Ming et al. (2014) Science 343. [5] Freissinet et al. (2015) JGR 120. [6] Eigenbrode et al. (2016) AGU P21D-08. [7] Freissinet

Analysis of volatile thiols in alcoholic beverages by simultaneous derivatization/extraction and liquid chromatography-high resolution mass spectrometry.

Science.gov (United States)

Vichi, Stefania; Cortés-Francisco, Nuria; Caixach, Josep

2015-05-15

A simultaneous derivatization/extraction method followed by liquid chromatography-electrospray-high resolution mass spectrometry for the determination of volatile thiols in hydroalcoholic matrixes was optimized and used to identify and quantify volatile thiols in wine and beer samples. The method was evaluated in terms of sensitivity, precision, accuracy and selectivity. The experimental LOQs of eleven thiols tested ranged between 0.01 ng/L and 10 ng/L. Intra-day relative standard deviation (RSD) was in general lower than 10% and inter-day RSD ranged between 10% and 30%. Recovery in the model and real matrixes ranged from 45% to 129%. The method was then applied for the analysis of four white wines and six beers. Five out of the eleven reference thiols were identified and quantified in the samples analyzed. The non-target approach, carried out by monitoring the diagnostic ion at m/z 275.9922 [C13H10ONSe](+) in the fragmentation spectrum, allowed detecting, in the same samples, fourteen non-target thiols. Copyright © 2014 Elsevier Ltd. All rights reserved.

A Prototype Sensor for In Situ Sensing of Fine Particulate Matter and Volatile Organic Compounds.

Science.gov (United States)

Ng, Chee-Loon; Kai, Fuu-Ming; Tee, Ming-Hui; Tan, Nicholas; Hemond, Harold F

2018-01-18

Air pollution exposure causes seven million deaths per year, according to the World Health Organization. Possessing knowledge of air quality and sources of air pollution is crucial for managing air pollution and providing early warning so that a swift counteractive response can be carried out. An optical prototype sensor (AtmOptic) capable of scattering and absorbance measurements has been developed to target in situ sensing of fine particulate matter (PM2.5) and volatile organic compounds (VOCs). For particulate matter testing, a test chamber was constructed and the emission of PM2.5 from incense burning inside the chamber was measured using the AtmOptic. The weight of PM2.5 particles was collected and measured with a filter to determine their concentration and the sensor signal-to-concentration correlation. The results of the AtmOptic were also compared and found to trend well with the Dylos DC 1100 Pro air quality monitor. The absorbance spectrum of VOCs emitted from various laboratory chemicals and household products as well as a two chemical mixtures were recorded. The quantification was demonstrated, using toluene as an example, by calibrating the AtmOptic with compressed gas standards containing VOCs at different concentrations. The results demonstrated the sensor capabilities in measuring PM2.5 and volatile organic compounds.

Signals of speciation: Volatile organic compounds resolve closely related sagebrush taxa, suggesting their importance in evolution

Science.gov (United States)

Deidre M. Jaeger; Justin B. Runyon; Bryce A. Richardson

2016-01-01

Volatile organic compounds (VOCs) play important roles in the environmental adaptation and fitness of plants. Comparison of the qualitative and quantitative differences in VOCs among closely related taxa and assessing the effects of environment on their emissions are important steps to deducing VOC function and evolutionary importance.

Profile of volatile organic compounds in exhaled breath changes as a result of gluten-free diet

NARCIS (Netherlands)

Baranska, Agnieszka; Tigchelaar, Ettje; Smolinska, Agnieszka; Dallinga, Jan W.; Moonen, Edwin J. C.; Dekens, Jackie A. M.; Wijmenga, Cisca; Zhernakova, Alexandra; van Schooten, Frederik J.

In the present longitudinal study, we followed volatile organic compounds (VOCs) excreted in exhaled breath of 20 healthy individuals over time, while adhering to a gluten-free diet for 4 weeks prior to adherence to a normal diet. We used gas chromatography coupled with mass spectrometry

Energy driven self-organization in nanoscale metallic liquid films.

Science.gov (United States)

Krishna, H; Shirato, N; Favazza, C; Kalyanaraman, R

2009-10-01

Nanometre thick metallic liquid films on inert substrates can spontaneously dewet and self-organize into complex nanomorphologies and nanostructures with well-defined length scales. Nanosecond pulses of an ultraviolet laser can capture the dewetting evolution and ensuing nanomorphologies, as well as introduce dramatic changes to dewetting length scales due to the nanoscopic nature of film heating. Here, we show theoretically that the self-organization principle, based on equating the rate of transfer of thermodynamic free energy to rate of loss in liquid flow, accurately describes the spontaneous dewetting. Experimental measurements of laser dewetting of Ag and Co liquid films on SiO(2) substrates confirm this principle. This energy transfer approach could be useful for analyzing the behavior of nanomaterials and chemical processes in which spontaneous changes are important.

Biodegradation of radioactive organic liquid waste from spent fuel reprocessing

International Nuclear Information System (INIS)

Ferreira, Rafael Vicente de Padua

2008-01-01

The research and development program in reprocessing of low burn-up spent fuel elements began in Brazil in 70's, originating the lab-scale hot cell, known as Celeste located at Nuclear and Energy Research Institute, IPEN - CNEN/SP. The program was ended at the beginning of 90's, and the laboratory was closed down. Part of the radioactive waste generated mainly from the analytical laboratories is stored waiting for treatment at the Waste Management Laboratory, and it is constituted by mixture of aqueous and organic phases. The most widely used technique for the treatment of radioactive liquid wastes is the solidification in cement matrix, due to the low processing costs and compatibility with a wide variety of wastes. However, organics are generally incompatible with cement, interfering with the hydration and setting processes, and requiring pre -treatment with special additives to stabilize or destroy them. The objective of this work can be divided in three parts: organic compounds characterization in the radioactive liquid waste; the occurrence of bacterial consortia from Pocos de Caldas uranium mine soil and Sao Sebastiao estuary sediments that are able to degrade organic compounds; and the development of a methodology to biodegrade organic compounds from the radioactive liquid waste aiming the cementation. From the characterization analysis, TBP and ethyl acetate were chosen to be degraded. The results showed that selected bacterial consortia were efficient for the organic liquid wastes degradation. At the end of the experiments the biodegradation level were 66% for ethyl acetate and 70% for the TBP. (author)

Volatile Organic Compunds (Environmental Health Student Portal)

Science.gov (United States)

... Weather Health Effects Take Action Water Pollution Water Pollution Home Chemicals and Pollutants Natural Disasters Drinking Water Waterborne Diseases & Illnesses Water Cycle Water Treatment Videos Games Experiments For Teachers Home Chemicals Volatile ...

Organic liquids as ''activ media'' in a holographic ionizing radiation dosimeter

International Nuclear Information System (INIS)

Nicolau-Rebigan, S.

1979-01-01

Some types of organic liquids for using as activ media in a holographic ionizing radiation dosimeter are presented. One outlined the advantages of the holographic dosimeter comparatively with those of common used dosimeters. One presented the advantages of utilization of the organic liquids comparatively with another chemical systems used in a holographic ionizing radiation dosimeter. (author)

Material degradation of liquid organic semiconductors analyzed by nuclear magnetic resonance spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Fukushima, Tatsuya; Yamamoto, Junichi; Fukuchi, Masashi; Kaji, Hironori, E-mail: kaji@scl.kyoto-u.ac.jp [Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan); Hirata, Shuzo; Jung, Heo Hyo; Adachi, Chihaya [Center for Organic Photonics and Electronics Research (OPERA), Kyusyu University, 744 Motooka, Nishi, Fukuoka 819-0395 (Japan); Hirata, Osamu; Shibano, Yuki [Nissan Chemical Industries, LTD, 722-1 Tsuboi, Funabashi 274-8507 (Japan)

2015-08-15

Liquid organic light-emitting diodes (liquid OLEDs) are unique devices consisting only of liquid organic semiconductors in the active layer, and the device performances have been investigated recently. However, the device degradation, especially, the origin has been unknown. In this study, we show that material degradation occurs in liquid OLEDs, whose active layer is composed of carbazole with an ethylene glycol chain. Nuclear magnetic resonance (NMR) experiments clearly exhibit that the dimerization reaction of carbazole moiety occurs in the liquid OLEDs during driving the devices. In contrast, cleavages of the ethylene glycol chain are not detected within experimental error. The dimerization reaction is considered to be related to the device degradation.

Volatile-mediated interactions between phylogenetically different soil bacteria

NARCIS (Netherlands)

Garbeva, P.; Hordijk, C.; Gerards, S.; Boer, de W.

2014-01-01

There is increasing evidence that organic volatiles play an important role in interactions between micro-organisms in the porous soil matrix. Here we report that volatile compounds emitted by different soil bacteria can affect the growth, antibiotic production and gene expression of the soil

International protocol on volatile organic compounds

International Nuclear Information System (INIS)

Gauthier, J.-P.

1992-01-01

In August 1991, negotiations between Canada, the USA, and 33 European countries led to an international protocol on reducing the emissions of volatile organic compounds (VOC), which are responsible for serious ozone pollution problems. This was the third transborder pollution agreement developed under the auspices of the United Nations Economic Commission for Europe. Certain aspects of negotiations related to an earlier protocol developed for SO 2 and nitrogen oxide emissions had reappeared during the VOC negotiations, and these aspects are discussed. The VOC protocol proposes three approaches to satisfy basic obligations: reducing VOC emissions of a country by 30%, reducing VOC emissions by 30% in certain regions, and ensuring a freeze in VOC emissions in a country starting on a specified date. The protocol also introduces a new concept, that of zones of tropospheric ozone management. In Canada, plans for management of nitrogen oxides and VOC have been adapted to the ozone problem, and the management plan has been developed by a consultation process involving all sectors of society including industry, environmental groups, and governments. In Canada, it will be sufficient to reduce total VOC emissions by 16% during a first phase and to increase these reductions slightly in the second phase. Special ozone management zones in the Quebec City/Windsor corridor and the Fraser River valley have been established

Volatile organic compound measurements in the California/Mexico border region during SCOS97

International Nuclear Information System (INIS)

Zielinska, B.; Sagebiel, J.; Harshfield, G.; Pasek, R.

2001-01-01

Measurements of volatile organic compounds (VOC) were carried out in the California/Mexico border region during the Southern California Ozone Study in the summer of 1997 (SCOS97). Integrated 3-h samples were collected in Rosarito (south of Tijuana, Mexico) and in Mexicali during intensive operational periods (IOP), twice per IOP day. VOC were collected using stainless-steel 6-l canisters; carbonyl compounds were collected using 2,4-dinitrophenylhydrazine (DNPH) impregnated C18 SepPak cartridges. The canister samples were analyzed for speciated volatile hydrocarbons (C 2 -C 12 ), CO, CO 2 , CH 4 , methyl t-butyl ether (MTBE), and halogenated hydrocarbons. DNPH-impregnated cartridges were analyzed for 14 C 1 -C 7 carbonyl compounds. The concentrations of all species were higher at Mexicali than in Rosarito. A good correlation between total non-methane hydrocarbons (TNMHC), CO, and other pollutants associated with motor vehicle emissions observed for Mexicali indicates that the main source of TNMHC at this site is vehicular traffic

Effects of trace volatile organic compounds on methane oxidation

Directory of Open Access Journals (Sweden)

Chiemchaisri Wilai

2001-01-01

Full Text Available The effects of volatile organic compounds (VOCs on methane oxidation in landfill cover soils were examined. The batch experiments were conducted using single and mixed VOCs, such as, dichloromethane (DCM, trichloroethylene (TCE, tetrachloroethylene (PCE, and benzene. The results from all combinations showed a decrease in methane oxidation rate with increase in VOC concentrations. Moreover, inhibition effects of TCE and DCM were found higher than benzene and PCE. The reduction of methane oxidation by benzene and PCE could be attributed to the toxicity effect, whereas TCE and DCM were found to exhibit the competitive-inhibition effect. When the soil was mixed with DCM, no methane oxidation was found. Damage to the cell's internal membrane was found in a methanotrophic culture exposed to VOC gases which is the attachment site of a key enzyme needed for methane oxidation

Improving production of volatile fatty acids from food waste fermentation by hydrothermal pretreatment.

Science.gov (United States)

Yin, Jun; Wang, Kun; Yang, Yuqiang; Shen, Dongsheng; Wang, Meizhen; Mo, Han

2014-11-01

Food waste (FW) was pretreated by a hydrothermal method and then fermented for volatile fatty acid (VFAs) production. The soluble substance in FW increased after hydrothermal pretreatment (⩽200 °C). Higher hydrothermal temperature would lead to mineralization of the organic compounds. The optimal temperature for organic dissolution was 180 °C, at which FW dissolved 42.5% more soluble chemical oxygen demand than the control. VFA production from pretreated FW fermentation was significantly enhanced compared with the control. The optimal hydrothermal temperature was 160 °C with a VFA yield of 0.908 g/g VSremoval. Butyrate and acetate were the prevalent VFAs followed by propionate and valerate. FW fermentation was inhibited after 200 °C pretreatment. The VFAs were extracted from the fermentation broth by liquid-liquid extraction. The VFA recovery was 50-70%. Thus, 0.294-0.411 g VFAs could be obtained per gram of hydrothermally pretreated FW (in dry weight) by this method. Copyright © 2014 Elsevier Ltd. All rights reserved.

Mesoporous thin films of ``molecular squares'' as sensors for volatile organic compounds

Energy Technology Data Exchange (ETDEWEB)

Keefe, M.H.; Slone, R.V.; Hupp, J.T.; Czaplewski, K.F.; Snurr, R.Q.; Stern, C.L.

2000-04-18

Mesoporous thin films of rhenium-based molecular squares, [Re(CO){sub 3}Cl(L)]{sub 4} (L = pyrazine, 4,4{prime}-bipyridine), have been utilized as sensors for volatile organic compounds (VOCs). The sensing was conducted using a quartz crystal microbalance with the target compounds present in the gas phase at concentrations ranging from 0.05 to 1 mM. Quartz crystal microbalance studies with these materials allowed for distinction between the following VOCs: (1) small aromatic versus aliphatic molecules of almost identical size and volatility and (2) an array of benzene molecules derivatized with electron donating/withdrawing substituents. The experiments suggest that the mesoporous host materials interact with VOC guest molecules through both van der Waals and weak charge-transfer interactions. In addition, size selectivity is shown by exposure of the molecular squares to cyclic ethers of differing size.

Heat Transfer Characteristics during Boiling of Immiscible Liquids Flowing in Narrow Rectangular Heated Channels

Directory of Open Access Journals (Sweden)

Yasuhisa Shinmoto

2017-11-01

Full Text Available The use of immiscible liquids for cooling of surfaces with high heat generation density is proposed based on the experimental verification of its superior cooling characteristics in fundamental systems of pool boiling and flow boiling in a tube. For the purpose of practical applications, however, heat transfer characteristics due to flow boiling in narrow rectangular channels with different small gap sizes need to be investigated. The immiscible liquids employed here are FC72 and water, and the gap size is varied as 2, 1, and 0.5 mm between parallel rectangular plates of 30 mm × 175 mm, where one plate is heated. To evaluate the effect of gap size, the heat transfer characteristics are compared at the same inlet velocity. The generation of large flattened bubbles in a narrow gap results in two opposite trends of the heat transfer enhancement due to thin liquid film evaporation and of the deterioration due to the extension of dry patch in the liquid film. The situation is the same as that observed for pure liquids. The latter negative effect is emphasized for extremely small gap sizes if the flow rate ratio of more-volatile liquid to the total is not reduced. The addition of small flow rate of less-volatile liquid can increase the critical heat flux (CHF of pure more-volatile liquid, while the surface temperature increases at the same time and assume the values between those for more-volatile and less-volatile liquids. By the selection of small flow rate ratio of more-volatile liquid, the surface temperature of pure less-volatile liquid can be decreased without reducing high CHF inherent in the less-volatile liquid employed. The trend of heat transfer characteristics for flow boiling of immiscible mixtures in narrow channels is more sensitive to the composition compared to the flow boiling in a round tube.

Distribution of enantiomers of volatile organic compounds in selected fruit distillates.

Science.gov (United States)

Vyviurska, Olga; Zvrškovcová, Helena; Špánik, Ivan

2017-01-01

The enantiomer ratios of chiral volatile organic compounds in fruit distillates were determined by multidimensional gas chromatography using solid-phase microextraction (SPME) as a sample treatment procedure. Linalool and its oxides, limonene, α-terpineol, and nerolidol, were present at the highest concentration levels, while significantly lower amounts of β-citronellol and lactones were found in the studied samples. However, almost all terpenoids mainly occur as a racemic or near-racemic mixture; enantiomer distribution of some chiral organic compounds in fruit distillates correlated to a botanical origin. In particular, a significant enantiomeric excess of (R)-linalool and (S)-α-terpineol was found only for pear brandy, and likewise the dominance (R)-limonene and the second eluted enantiomer of nerolidol for Sorbus domestica and strawberry, respectively. The distribution of γ-lactones stereoisomers was more nonspecific, with a general excess of the R-enantiomer. © 2016 Wiley Periodicals, Inc.

Characterisation of selected volatile organic compounds in ...

African Journals Online (AJOL)

kshale

2013-05-15

May 15, 2013 ... have entered the commercial market, both in rural areas ... nation of volatile compounds include: gas chromate- graphy (GC) ... prior to the actual analysis, various extraction methods ..... traditional and industrial 'orujo' spirits.

Advances in the determination of volatile organic solvents and other organic pollutants by gas chromatography with thermal desorption sampling and injection

Energy Technology Data Exchange (ETDEWEB)

Fabbri, A.; Crescentini, G.; Mangani, F.; Mastrogiacomo, A.R.; Bruner, F.

1987-11-01

The problem of the separation of 34 volatile organic chlorinated compounds is solved by using three different GC columns selected according to the needs of the particular separation required. The effect of water vapor contained as moisture in the trapped air on the retention of some characteristic compounds is studied. The influence of dead volumes on trap injection is also studied.

VOC and HAP recovery using ionic liquids

Energy Technology Data Exchange (ETDEWEB)

Michael R. Milota : Kaichang Li

2007-05-29

During the manufacture of wood composites, paper, and to a lesser extent, lumber, large amounts of volatile organic compounds (VOCs) such as terpenes, formaldehyde, and methanol are emitted to air. Some of these compounds are hazardous air pollutants (HAPs). The air pollutants produced in the forest products industry are difficult to manage because the concentrations are very low. Presently, regenerative thermal oxidizers (RTOs and RCOs) are commonly used for the destruction of VOCs and HAPs. RTOs consume large amounts of natural gas to heat air and moisture. The combustion of natural gas generates increased CO2 and NOx, which have negative implications for global warming and air quality. The aforementioned problems are addressed by an absorption system containing a room-temperature ionic liquid (RTIL) as an absorbent. RTILs are salts, but are in liquid states at room temperature. RTILs, an emerging technology, are receiving much attention as replacements for organic solvents in industrial processes with significant cost and environmental benefits. Some of these processes include organic synthesis, extraction, and metal deposition. RTILs would be excellent absorbents for exhausts from wood products facilities because of their unique properties: no measurable vapor pressure, high solubility of wide range of organic compounds, thermal stability to 200°C (almost 400°F), and immisciblity with water. Room temperature ionic liquids were tested as possible absorbents. Four were imidizolium-based and were eight phosphonium-based. The imidizolium-based ionic liquids proved to be unstable at the conditions tested and in the presence of water. The phosphonium-based ionic liquids were stable. Most were good absorbents; however, cleaning the contaminates from the ionic liquids was problematic. This was overcome with a higher temperature (120°C) than originally proposed and a very low pressure (1 kPa. Absorption trials were conducted with tetradecy

Microwave-assisted ionic liquid homogeneous liquid-liquid microextraction coupled with high performance liquid chromatography for the determination of anthraquinones in Rheum palmatum L.

Science.gov (United States)

Wang, Zhibing; Hu, Jianxue; Du, Hongxia; He, Shuang; Li, Qing; Zhang, Hanqi

2016-06-05

The microwave-assisted ionic liquid homogeneous liquid-liquid microextraction (MA-IL-HLLME) coupled with high performance liquid chromatography with diode array detection (HPLC-DAD) was developed for the determination of anthraquinones, including aloe-emodin, emodin, chrysophanol and physcion in root of Rheum palmatum L. Several experimental parameters influencing the extraction efficiency, including amount of sample, type and volume of ionic liquid, volume and pH value of extraction medium, microwave power and extraction time, concentration of NH4PF6 as well as centrifugal condition were optimized. When 140μL of ionic liquid ([C8MIM][BF4]) was used as an extraction solvent, target analytes can be extracted from sample matrix in one minute with the help of microwave irradiation. The MA-IL-HLLME is simple and quick. The calibration curves exhibited good linear relationship (r>0.9984). The limits of detection and quantification were in the range of 0.015-0.026 and 0.051-0.088μgmL(-1), respectively. The spiked recovery for each analyte was in the range of 81.13-93.07% with relative standard deviations lower than 6.89%. The present method is free of volatile organic solvents, and represents lower expenditures of sample, extraction time and solvent, compared with ultrasonic and heat reflux extraction. The results indicated that the present method can be successfully applied to the determination of anthraquinones in medicinal plant. Copyright © 2016 Elsevier B.V. All rights reserved.

Aerosol volatility in a boreal forest environment

Science.gov (United States)

Häkkinen, S. A. K.; ńijälä, M.; Lehtipalo, K.; Junninen, H.; Virkkula, A.; Worsnop, D. R.; Kulmala, M.; Petäjä, T.; Riipinen, I.

2012-04-01

Climate and health effects of atmospheric aerosols are determined by their properties such as their chemical composition. Aerosol chemical composition can be studied indirectly by measuring volatility of aerosol particles. The volatility of submicron aerosol particles (20-500 nm) was studied in a boreal forest site at SMEAR II (Station for Measuring Ecosystem-Atmosphere Relations II) station (Vesala et al., 1998) in Hyytiälä, Finland, during 01/2008-05/2010. The instrument used for the measurements was VDMPS (Volatility Differential Mobility Particle Sizer), which consists of two separate instruments: DMPS (Differential Mobility Particle Sizer, Aalto et al., 2001) and TD (Thermodenuder, Wehner et al., 2002). Aerosol evaporation was examined by heating the aerosol and comparing the total aerosol mass before and after heating. In the VDMPS system ambient aerosol sample was heated up to temperatures ranging from 80 °C to 280 °C. The higher the heating temperature was the more aerosol material was evaporated. There was a non-volatile residual present in aerosol particles when heated up to 280 °C. This residual explained (20±8)% of the total aerosol mass. Aerosol non-volatile mass fraction was highest during winter and smallest during summer months. The role of black carbon in the observed non-volatile residual was determined. Black carbon explained 40 to 90% of the non-volatile mass. Especially during colder seasons noticeable amount of non-volatile material, something else than black carbon, was observed. According to Kalberer et al. (2004) some atmospheric organic species can form polymers that have high evaporation temperatures. Also low-volatile organic salts may contribute to the non-volatile aerosol (Smith et al., 2010). Aerosol mass composition measured directly with AMS (Aerosol Mass Spectrometer, Jayne et al., 2000) was analyzed in order to examine the properties of the non-volatile material (other than black carbon). The AMS measurements were performed

A portion of plant airborne communication is endorsed by uptake and metabolism of volatile organic compounds.

Science.gov (United States)

Matsui, Kenji

2016-08-01

Plants have the ability to sense volatile organic compounds (VOCs) so as to efficiently adapt to their environment. The mechanisms underlying such plant 'olfactory' systems are largely unknown. Here I would like to propose that the metabolism of VOCs in plant tissues is one of the mechanisms by which plants sense VOCs. During the gas-exchange that is essential for photosynthesis, VOCs in the atmosphere are taken into the intercellular spaces of leaves. Each VOC is partitioned between the gas phase (intercellular space) and liquid phase (cell wall) at a certain ratio determined by Henry's law. The VOCs in the cell wall diffuse through the plasma membrane to the cytosol depending on their oil/water partition coefficients. Plants detoxify some VOCs, especially those that are oxidized, through glycosylation, glutathionylation, and reduction. These metabolic processes lower the concentration of VOCs in the cytosol, which facilitates further cytosolic uptake. As a result, vigorous metabolism of VOCs in the cytosol can lead to a substantial accumulation of VOC metabolites and the depletion of glutathione or NADPH. One such metabolite (a VOC glycoside) is known to mount a direct defense against herbivores, whilst deprivation of glutathione and NADPH can fortify plants with responses similar to the oxidative stress response. Copyright © 2016 Elsevier Ltd. All rights reserved.

The prey’s scent – Volatile organic compound mediated interactions between soil bacteria and their protist predators

NARCIS (Netherlands)

Schulz, K.B.; Geisen, Stefan; Wubs, E.R.J.; Song, C.; Boer, de W.; Garbeva, Paolina

2017-01-01

Protists are major predators of bacteria in soils. However, it remains unknown how protists sense their prey in this highly complex environment. Here, we investigated whether volatile organic compounds (VOCs) of six phylogenetic distinct soil bacteria affect the performance of three different soil

Direct Capture of Organic Acids From Fermentation Media Using Ionic Liquids

Energy Technology Data Exchange (ETDEWEB)

Klasson, K.T.

2004-11-03

Several ionic liquids have been investigated for the extraction of organic acids from fermentation broth. Partitioning of representative organic acids (lactic, acetic, and succinic) between aqueous solution and nine hydrophobic ionic liquids was measured. The extraction efficiencies were strongly dependent on pH of the aqueous phase. Distribution coefficient was very good (approximately 60) at low succinic acid concentrations for one of the ionic liquids (trihexyltetradecylphosphonium methanesulfonate) at neutral pH. However, this ionic liquid had to be diluted with nonanol due to its high viscosity in order to be useful. A diluent (trioctylamine) was also added to this mixture. The results suggest that an extraction system based on ionic liquids may be feasible for succinic acid recovery from fermentation broth and that two ideal extraction stages are needed to reduce the concentration from 33 g/L to 1 g/L of succinic acid. Further studies are needed to evaluate other issues related to practical applications, including ionic liquid loss in the process, toxicity effects of ionic liquids during simultaneous fermentation and extractions.

Solid phase microextraction: measurement of volatile organic compounds (VOCs) in Dhaka City air pollution.

Science.gov (United States)

Hussam, A; Alauddin, M; Khan, A H; Chowdhury, D; Bibi, H; Bhattacharjee, M; Sultana, S

2002-08-01

A solid phase microextraction (SPME) technique was applied for the sampling of volatile organic compounds (VOCs) in ambient air polluted by two stroke autorickshaw engines and automobile exhausts in Dhaka city, Bangladesh. Analysis was carried out by capillary gas chromatography (GC) and GC-mass spectrometry (MS). The methodology was tested by insitu sampling of an aromatic hydrocarbon mixture gas standard with a precision of +/-5% and an average accuracy of 1-20%. The accuracy for total VOCs concentration measurement was about 7%. VOC's in ambient air were collected by exposing the SPME fiber at four locations in Dhaka city. The chromatograms showed signature similar to that of unburned gasoline (petrol) and weathered diesel containing more than 200 organic compounds; some of these compounds were positively identified. These are normal hydrocarbons pentane (n-C5H2) through nonacosane (n-C29H60), aromatic hydrocarbons: benzene, toluene, ethylbenzene, n-propylbenzene, n-butylbenzene, 1,3,5-trimethylbenzene, xylenes, and 1-isocyanato-3-methoxybenzene. Two samples collected near an autorickshaw station contained 783000 and 1479000 microg/m3 of VOCs. In particular, the concentration of toluene was 50-100 times higher than the threshold limiting value of 2000 microg/m3. Two other samples collected on street median showed 135000 microg/m3 and 180000 microg/m3 of total VOCs. The method detection limit of the technique for most semi-volatile organic compounds was 1 microg/m3.

Material degradation of liquid organic semiconductors analyzed by nuclear magnetic resonance spectroscopy

Directory of Open Access Journals (Sweden)

Tatsuya Fukushima

2015-08-01

Full Text Available Liquid organic light-emitting diodes (liquid OLEDs are unique devices consisting only of liquid organic semiconductors in the active layer, and the device performances have been investigated recently. However, the device degradation, especially, the origin has been unknown. In this study, we show that material degradation occurs in liquid OLEDs, whose active layer is composed of carbazole with an ethylene glycol chain. Nuclear magnetic resonance (NMR experiments clearly exhibit that the dimerization reaction of carbazole moiety occurs in the liquid OLEDs during driving the devices. In contrast, cleavages of the ethylene glycol chain are not detected within experimental error. The dimerization reaction is considered to be related to the device degradation.

Volatility study of [C1C1im][NTf2] and [C2C3im][NTf2] ionic liquids

International Nuclear Information System (INIS)

Rocha, Marisa A.A.; Ribeiro, Filipe M.S.; Schröder, Bernd; Coutinho, João A.P.; Santos, Luís M.N.B.F.

2014-01-01

Highlights: • Vapor pressures of [C 1 C 1 im][NTf 2 ] and [C 2 C 3 im][NTf 2 ] ionic liquids are reported. • [C 1 C 1 im][NTf 2 ] presents higher enthalpy and entropy of vaporization than expected. • The high volatility of [C 2 C 3 im][NTf 2 ] is a result from its asymmetric character. -- Abstract: Vapor pressures of 1,3-dimethylimidazolium bis(trifluoromethylsulfonyl)imide, ([C 1 C 1 im][NTf 2 ]) and 1-ethyl-3-propylimidazolium bis(trifluoromethylsulfonyl)imide, ([C 2 C 3 im][NTf 2 ]) ionic liquids were measured as a function of temperature using a Knudsen effusion apparatus combined with a quartz crystal microbalance. Enthalpies and entropies of vaporization were derived from the fitting of vapor pressure and temperature results to the Clarke and Glew equation. [C 1 C 1 im][NTf 2 ] presents a higher enthalpy and entropy of vaporization than the neighboring members of the series. The enthalpy of vaporization of [C 2 C 3 im][NTf 2 ] lies in between the asymmetric and symmetric ionic liquid series, reflecting a decrease in the electrostatic interactions due to a decrease of the charge accessibility between the ionic pairs when the methyl group is replaced by an ethyl group. The obtained higher volatility of [C 2 C 3 im][NTf 2 ] arises from its asymmetric character, leading to an higher entropic contribution that compensates the enthalpic penalty. The border conditions ([C 1 C 1 im][NTf 2 ], [C 2 C 1 im][NTf 2 ] and [C 2 C 2 im][NTf 2 ]), topology ([C 2 C 3 im][NTf 2 ]) and symmetry/asymmetry of the ILs effect were evaluated and rationalized based on a comparative analysis of the thermodynamic properties, enthalpies and entropies of vaporization

Measuring volatile organic compounds and stable isotopes emitted from trees and soils of the Biosphere 2 Rainforest

Science.gov (United States)

Meraz, J. C.; Meredith, L. K.; Van Haren, J. L. M.; Volkmann, T. H. M.

2017-12-01

Rainforest trees and soils play an important role in volatile organic compound (VOC) emissions. It is known that many rainforest tree species emit these organic compounds, such as terpenes, which can have an impact on the atmosphere and can be indicative of their metabolic functions. Some VOCs also absorb infrared radiation at wavelengths at which water isotopes are measured with laser spectrometers. Normal concentrations are not high enough for ambient sampling, but increased concentrations resulting from soil and plant samples extracted using equilibrium methods affect observed isotope ratios. There is thus a need to characterize volatile emissions from soil and plant samples, and to develop better methods to account for VOC interference during water isotope measurements. In this study, we collected soil and leaf samples from plants of the Biosphere 2 Rainforest Biome, a mesocosm system created to stimulate natural tropical rainforest habitats . Volatile concentrations were measured using a Gasmet DX4015 FTIR analyzer and a custom sampling system with sulfur hexafluoride (SF6) used as a tracer gas to test for leakage, and a commercial laser spectrometer was used for isotopic analysis. We determined that the different types of tree species emit different kinds of VOCs, such as isoprenes, alcohols, and aldehydes, that will potentially have to be accounted for. This study will help build the understanding of which organic compounds are emitted and develop new methods to test for water isotopes and gas fluxes in clear and precise measures. Such measures can help characterize the functioning of environmental systems such as the Biosphere 2 Rainforest Biome.

Analysis of Non-Volatile Chemical Constituents of Menthae Haplocalycis Herba by Ultra-High Performance Liquid Chromatography-High Resolution Mass Spectrometry

Directory of Open Access Journals (Sweden)

Lu-Lu Xu

2017-10-01

Full Text Available Menthae Haplocalycis herba, one kind of Chinese edible herbs, has been widely utilized for the clinical use in China for thousands of years. Over the last decades, studies on chemical constituents of Menthae Haplocalycis herba have been widely performed. However, less attention has been paid to non-volatile components which are also responsible for its medical efficacy than the volatile constituents. Therefore, a rapid and sensitive method was developed for the comprehensive identification of the non-volatile constituents in Menthae Haplocalycis herba using ultra-high performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry (UHPLC-LTQ-Orbitrap. Separation was performed with Acquity UPLC® BEH C18 column (2.1 mm × 100 mm, 1.7 μm with 0.2% formic acid aqueous solution and acetonitrile as the mobile phase under gradient conditions. Based on the accurate mass measurement (<5 ppm, MS/MS fragmentation patterns and different chromatographic behaviors, a total of 64 compounds were unambiguously or tentatively characterized, including 30 flavonoids, 20 phenolic acids, 12 terpenoids and two phenylpropanoids. Finally, target isolation of three compounds named Acacetin, Rosmarinic acid and Clemastanin A (first isolated from Menthae Haplocalycis herba were performed based on the obtained results, which further confirmed the deduction of fragmentation patterns and identified the compounds profile in Menthae Haplocalycis herba. Our research firstly systematically elucidated the non-volatile components of Menthae Haplocalycis herba, which laid the foundation for further pharmacological and metabolic studies. Meanwhile, our established method was useful and efficient to screen and identify targeted constituents from traditional Chinese medicine extracts.

Process and device for liquid organic waste processing by sulfuric mineralization

International Nuclear Information System (INIS)

Aspart, A.; Gillet, B.; Lours, S.; Guillaume, B.

1990-01-01

In a chemical reactor containing sulfuric acid are introduced the liquid waste and nitric acid at a controlled flow rate for carbonization of the waste and oxidation of carbon on sulfur dioxide, formed during carbonization, regenerating simultaneously sulfuric acid. Optical density of the liquid is monitored to stop liquid waste feeding above a set-point. The liquid waste can be an organic solvent such as TBP [fr

Operation of a catalytic reverse flow reactor for the purification of air contamined with volatile organic compounds

NARCIS (Netherlands)

van de Beld, L.; van de Beld, L.; Westerterp, K.R.

1997-01-01

Catalytic oxidation in a reverse flow reactor is an attractive process for the decontamination of air polluted with volatile organic compounds (VOCs). In this paper several aspects of operating this type of reactor for air purification under strongly varying conditions will be discussed. For a

Effects of capillarity and heterogeneity on flow of organic liquid in soil

NARCIS (Netherlands)

Wipfler, E.L.

2003-01-01

Contamination of groundwater by organic liquids, such as gasoline, fuel oils and chlorinated hydrocarbons, forms a serious treat to subsurface water resources. These liquids have a low miscibility with water and move as a discrete liquid phase. A small part of the liquid may dissolve in water and

Emissions of volatile organic compounds (VOCs) from oil and natural gas activities: compositional comparison of 13 major shale basins via NOAA airborne measurements

Science.gov (United States)

Gilman, J.; Lerner, B. M.; Aikin, K. C.; De Gouw, J. A.; Koss, A.; Yuan, B.; Warneke, C.; Peischl, J.; Ryerson, T. B.; Holloway, J. S.; Graus, M.; Tokarek, T. W.; Isaacman-VanWertz, G. A.; Sueper, D.; Worsnop, D. R.

2015-12-01

The recent and unprecedented increase in natural gas production from shale formations is associated with a rise in the production of non-methane volatile organic compounds (VOCs) including natural gas plant liquids (e.g., ethane, propane, and butanes) and liquid lease condensate (e.g., pentanes, hexanes, aromatics and cycloalkanes). Since 2010, the production of natural gas liquids and the amount of natural gas vented/flared has increased by factors of ~1.28 and 1.57, respectively (U.S. Energy and Information Administration), indicating an increasingly large potential source of hydrocarbons to the atmosphere. Emission of VOCs may affect local and regional air quality due to the potential to form tropospheric ozone and organic particles as well as from the release of toxic species such as benzene and toluene. The 2015 Shale Oil and Natural Gas Nexus (SONGNex) campaign studied emissions from oil and natural gas activities across the central United States in order to better understand their potential air quality and climate impacts. Here we present VOC measurements from 19 research flights aboard the NOAA WP-3D over 11 shale basins across 8 states. Non-methane hydrocarbons were measured using an improved whole air sampler (iWAS) with post-flight analysis via a custom-built gas chromatograph-mass spectrometer (GC-MS). The whole air samples are complimented by higher-time resolution measurements of methane (Picarro spectrometer), ethane (Aerodyne spectrometer), and VOCs (H3O+ chemical ionization mass spectrometer). Preliminary analysis show that the Permian Basin on the New Mexico/Texas border had the highest observed VOC mixing ratios for all basins studied. We will utilize VOC enhancement ratios to compare the composition of methane and VOC emissions for each basin and the associated reactivities of these gases with the hydroxyl radical, OH, as a proxy for potential ozone formation.

Determination of Partition coefficients for a Mixture of Volatile Organic Compounds in Rats and Humans at Different Life Stages

National Research Council Canada - National Science Library

Mahle, Deidre A; Gearhart, Jeffrey M; Godfrey, Richard J; Mattie, David R; Cook, Robert S; Grisby, Claude C

2004-01-01

.... Partition coefficients (PCs) are an integral component of pharmacokinetic models and determining differences in tissue partitioning of volatile organic chemicals across life stages can help reduce the uncertainty in risk assessment...

Investigation of organic liquid-scintillator optical properties

Energy Technology Data Exchange (ETDEWEB)

Winter, Juergen; Feilitzsch, Franz von; Goeger-Neff, Marianne; Lewke, Timo; Meindl, Quirin; Oberauer, Lothar; Potzel, Walter; Todor, Sebastian; Wurm, Michael [Physik Department E15, Technische Universitaet Muenchen, James-Franck-Str., 85748 Garching (Germany); Marrodan Undagoitia, Teresa [Physik Department E15, Technische Universitaet Muenchen, James-Franck-Str., 85748 Garching (Germany); Physik-Institut, Universitaet Zuerich (Switzerland)

2009-07-01

The characterization of different organic liquid-scintillator mixtures is an important step towards the design of a large-scale detector such as LENA (Low Energy Neutrino Astronomy). Its physics goals, extending from particle and geological to astrophysical issues, set high demands on the optical properties of the liquid scintillator. Therefore, small-scale experiments are carried out in order to optimize the final scintillator mixture. PXE, LAB, and dodecane are under consideration as solvents. Setups for the determination of scintillator properties are presented, such as attenuation length, light yield, emission spectra, fluorescence decay times, and quenching factors. Furthermore, results are discussed.

A Prototype Sensor for In Situ Sensing of Fine Particulate Matter and Volatile Organic Compounds

Directory of Open Access Journals (Sweden)

Chee-Loon Ng

2018-01-01

Full Text Available Air pollution exposure causes seven million deaths per year, according to the World Health Organization. Possessing knowledge of air quality and sources of air pollution is crucial for managing air pollution and providing early warning so that a swift counteractive response can be carried out. An optical prototype sensor (AtmOptic capable of scattering and absorbance measurements has been developed to target in situ sensing of fine particulate matter (PM2.5 and volatile organic compounds (VOCs. For particulate matter testing, a test chamber was constructed and the emission of PM2.5 from incense burning inside the chamber was measured using the AtmOptic. The weight of PM2.5 particles was collected and measured with a filter to determine their concentration and the sensor signal-to-concentration correlation. The results of the AtmOptic were also compared and found to trend well with the Dylos DC 1100 Pro air quality monitor. The absorbance spectrum of VOCs emitted from various laboratory chemicals and household products as well as a two chemical mixtures were recorded. The quantification was demonstrated, using toluene as an example, by calibrating the AtmOptic with compressed gas standards containing VOCs at different concentrations. The results demonstrated the sensor capabilities in measuring PM2.5 and volatile organic compounds.

Low concentration volatile organic pollutants removal in combined adsorber-desorber-catalytic reactor system

Directory of Open Access Journals (Sweden)

Arsenijević Zorana

2008-01-01

Full Text Available The removal of volatile organic compounds (VOCs from numerous emission sources is of crucial importance due to more rigorous demands on air quality. Different technologies can be used to treat the VOCs from effluent gases: absorption, physical adsorption, open flame combustion, thermal and catalytic incineration. Their appropriateness for the specific process depends on several factors such as efficiency, energy consumption, secondary pollution, capital investments etc. The distinctive features of the catalytic combustion are high efficiency and selectivity toward be­nign products, low energy consumption and absence of secondary polluti­on. The supported noble catalysts are widely used for catalytic incineration due to their low ignition temperatures and high thermal and chemical stability. In our combined system adsorption and desorption are applied in the spouted bed with draft tube (SBDT unit. The annular zone, loaded with sorbent, was divided in adsorption and desorption section. Draft tube enabled sorbent recirculation between sections. Combustion of desorbed gases to CO2 and water vapor are realized in additive catalytic reactor. This integrated device provided low concentrations VOCs removal with reduced energy consumption. Experiments were conducted on a pilot unit of 220 m3/h nominal capacity. The sorbent was activated carbon, type K81/B - Trayal Corporation, Krusevac. A sphere shaped commercial Pt/Al2O3 catalyst with "egg-shell" macro-distribution was used for the investigation of xylene deep oxidation. Within this paper the investigations of removal of xylene vapors, a typical pollutant in production of liquid pesticides, in combined adsorber/desorber/catalytic reactor system is presented.

Investigation of michelson interferometer for volatile organic compound sensor

International Nuclear Information System (INIS)

Marzuarman; Rivai, Muhammad; Sardjono, Tri Arief; Purwanto, Djoko

2017-01-01

The sensor device is required to monitor harmful gases in the environments and industries. Many volatile organic compounds adsorbed on the sensor material will result in changes of the optical properties including the refractive index and the film thickness. This study designed and realized a vapor detection device using the principle of Michelson Interferometer. The laser light beamed with a wavelength of 620 nm was divided by using a beam splitter. Interference occurredwhen the two separated lights were recombined. The phase difference between the two beams determined whether the interference would destruct or construct each other to produce the curved fringes. The vapor samples used in these experiments were ethanol and benzene. The results showed that the ethanol concentration of 1611-32210 ppm produced a fringe shift of 197 pixels, while the concentration of benzene of 964-19290 ppm produced a fringe shift of 273 pixels. (paper)

The Effectivity of Marine Bio-activator and Surimi Liquid Waste Addition of Characteristics Liquid Organic Fertilizer from Sargassum sp.

Directory of Open Access Journals (Sweden)

Putri Wening Ratrinia

2017-02-01

Full Text Available AbstractOrganic fertilizer is highly recommended for soil and plant because it can improve the productivity and repair physical, chemical, and biological of soil. Sargassum sp. and surimi liquid wastes contain organic matter and nutrient needed by plants and soils. The addition of marine bio-activator which contains bacterial isolates from litter mangrove serves to accelerate the composting time and increases the activity of microorganisms in the decomposition process. The purpose of this study was to determine optimum time and the best formulation of decomposition process organic fertilizer. Raw materials used a waste of seaweed Sargassum sp., marine bio-activator and surimi liquid waste from catfish (Clarias sp.. The research was conducted six treatments control, Sargassum sp. + marine bio-activator, surimi liquid waste , Sargassum sp. + marine bio-activator + surimi liquid waste 80%, 90%, 100%. All treatments were fermented for 9 days and analysed the C-organic, total N, C/N ratio, P2O5, K2O on days 0, 3, 6 and 9. The results showed the optimum fermentation period was on the 6th day. The most optimum concentration of surimi liquid waste added was at a concentration of 90%, with characteristics of the products was C-organic 0.803±0.0115%, total N 740.063±0.0862 ppm, C/N ratio 10.855±0.1562, P2O5 425.603±0.2329 ppm, K2O 2738.627±0.2836 ppm.

The Effectivity of Marine Bio-activator and Surimi Liquid Waste Addition of Characteristics Liquid Organic Fertilizer from Sargassum sp.

Directory of Open Access Journals (Sweden)

Putri Wening Ratrinia

2016-12-01

Full Text Available Organic fertilizer is highly recommended for soil and plant because it can improve the productivity and repair physical, chemical, and biological of soil. Sargassum sp. and surimi liquid wastes contain organic matter and nutrient needed by plants and soils. The addition of marine bio-activator which contains bacterial isolates from litter mangrove serves to accelerate the composting time and increases the activity of microorganisms in the decomposition process. The purpose of this study was to determine optimum time and the best formulation of decomposition process organic fertilizer. Raw materials used a waste of seaweed Sargassum sp., marine bio-activator and surimi liquid waste from catfish (Clarias sp.. The research was conducted six treatments control, Sargassum sp. + marine bio-activator, surimi liquid waste , Sargassum sp. + marine bio-activator + surimi liquid waste 80%, 90%, 100%. All treatments were fermented for 9 days and analysed the C-organic, total N, C/N ratio, P2 O5 , K2 O on days 0, 3, 6 and 9. The results showed the optimum fermentation period was on the 6th day. The most optimum concentration of surimi liquid waste added was at a concentration of 90%, with characteristics of the products was C-organic 0.803 ± 0.0115 %, total N 740.063 ± 0.0862 ppm, C/N ratio 10.855 ± 0.1562, P2 O5 425.603 ± 0.2329 ppm, K2 O 2738.627 ± 0.2836 ppm.

Secondary organic aerosol formation and composition from the photo-oxidation of methyl chavicol (estragole)

Science.gov (United States)

Pereira, K. L.; Hamilton, J. F.; Rickard, A. R.; Bloss, W. J.; Alam, M. S.; Camredon, M.; Muñoz, A.; Vázquez, M.; Borrás, E.; Ródenas, M.

2014-06-01

The increasing demand for palm oil for uses in biofuel and food products is leading to rapid expansion of oil palm agriculture. Methyl chavicol (also known as estragole and 1-allyl-4-methoxybenzene) is an oxygenated biogenic volatile organic compound (VOC) that was recently identified as the main floral emission from an oil palm plantation in Malaysian Borneo. The emissions of methyl chavicol observed may impact regional atmospheric chemistry, but little is known of its ability to form secondary organic aerosol (SOA). The photo-oxidation of methyl chavicol was investigated at the European Photoreactor chamber as a part of the atmospheric chemistry of methyl chavicol (ATMECH) project. Aerosol samples were collected using a particle into liquid sampler (PILS) and analysed offline using an extensive range of instruments including; high-performance liquid chromatography mass spectrometry (HPLC-ITMS), high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (HPLC-QTOFMS) and Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). The SOA yield was determined as 18 and 29% for an initial VOC mixing ratio of 212 and 460 ppbv (parts per billion by volume) respectively; using a VOC:NOx ratio of ~5:1. In total, 59 SOA compounds were observed and the structures of 10 compounds have been identified using high-resolution tandem mass spectrometry. The addition of hydroxyl and/or nitro-functional groups to the aromatic ring appears to be an important mechanistic pathway for aerosol formation. This results in the formation of compounds with both low volatility and high O:C ratios, where functionalisation rather than fragmentation is mainly observed as a result of the stability of the ring. The SOA species observed can be characterised as semi-volatile to low-volatility oxygenated organic aerosol (SVOOA and LVOOA) components and therefore may be important in aerosol formation and growth.

Processing of volatile organic compounds by microwave plasmas

International Nuclear Information System (INIS)

Mizeraczyk, J.; Jasinski, M.; Dors, M.; Zakrzewski, Z.

2011-01-01

In this paper atmospheric pressure microwave discharge methods and devices used for producing the nonthermal plasmas for processing of gases are presented. The main part of the paper concerns the microwave plasma sources (MPSs) for environmental protection applications. A few types of the MPSs, i.e. waveguidebased surface wave sustained MPS, coaxial-line-based and waveguide-based nozzle-type MPSs, waveguidebased nozzleless cylinder-type MPS and MPS for microdischarges are presented. Also, results of the laboratory experiments on the plasma processing of several highly-concentrated (up to several tens percent) volatile organic compounds (VOCs), including Freon-type refrigerants, in the moderate (200-400 W) waveguide-based nozzletype MPS (2.45 GHz) are presented. The results showed that the microwave discharge plasma fully decomposed the VOCs at relatively low energy cost. The energy efficiency of VOCs decomposition reached 1000 g/kWh. This suggests that the microwave discharge plasma can be a useful tool for environmental protection applications. In this paper also results of the use of the waveguide-based nozzleless cylinder-type MPS to methane reforming into hydrogen are presented. (author)

[Indoor volatile organic compounds: concentrations, sources, variation factors].

Science.gov (United States)

Palot, A; Charpin-Kadouch, C; Ercoli, J; Charpin, D

2008-06-01

Volatile organic compounds (V.O.C.) are part of urban air pollution and are also generated indoors from cleaning and maintenance products. VOC measurements are, on average, 10 times higher within homes than outside. Results of the national survey led by the Observatoire National de la Qualité de l'Air Intérieur demonstrated that up to 25% of French homes have very high or high concentrations of VOC. Indoor levels depend mainly on indoor sources. Aldehydes are included in many everyday life products. VOC originate from various household decorating and cleaning products. Some products are less detrimental to the environment and health and have special labelling. Indoor VOC levels also depend on the rate of air exchange and on household characteristics such as indoor temperature and humidity, age of the building, presence of smokers, and communication with a garage. The public may participate in maintaining good indoor air quality and the authorities should also improve regulations. VOC are part of everyday air pollution. Their sources and concentrations should be better monitored.

Processing of volatile organic compounds by microwave plasmas

Energy Technology Data Exchange (ETDEWEB)

Mizeraczyk, J. [Centre for Plasma and Laser Engineering, Szewalski Institute of Fluid-Flow Machinery, Polish Academy of Sciences, Gdansk (Poland); Department of Marine Electronics, Gdynia Martime University, Gdynia (Poland); Jasinski, M.; Dors, M.; Zakrzewski, Z. [Centre for Plasma and Laser Engineering, Szewalski Institute of Fluid-Flow Machinery, Polish Academy of Sciences, Gdansk (Poland)

2011-07-01

In this paper atmospheric pressure microwave discharge methods and devices used for producing the nonthermal plasmas for processing of gases are presented. The main part of the paper concerns the microwave plasma sources (MPSs) for environmental protection applications. A few types of the MPSs, i.e. waveguidebased surface wave sustained MPS, coaxial-line-based and waveguide-based nozzle-type MPSs, waveguidebased nozzleless cylinder-type MPS and MPS for microdischarges are presented. Also, results of the laboratory experiments on the plasma processing of several highly-concentrated (up to several tens percent) volatile organic compounds (VOCs), including Freon-type refrigerants, in the moderate (200-400 W) waveguide-based nozzletype MPS (2.45 GHz) are presented. The results showed that the microwave discharge plasma fully decomposed the VOCs at relatively low energy cost. The energy efficiency of VOCs decomposition reached 1000 g/kWh. This suggests that the microwave discharge plasma can be a useful tool for environmental protection applications. In this paper also results of the use of the waveguide-based nozzleless cylinder-type MPS to methane reforming into hydrogen are presented. (author)

Resonance Raman spectroscopy of volatile organics -- Carbon tetrachloride

International Nuclear Information System (INIS)

Barletta, R.E.; Veligdan, J.T.

1994-09-01

Volatile organic chemicals are a class of pollutants which are regulated at very low levels by the EPA. Consequently a need exists as a part of site remediation efforts within DOE to develop technologies which will allow for the in situ monitoring of these chemicals. Resonance Raman spectroscopy is a potential technique to accomplish this if the resonance enhancement is sufficiently high. Carbon tetrachloride was selected as a test case. Measurements under resonance conditions at 248 nm showed an enhancement factor of 2 x 10 4 . Using this value an estimate of the sensitivity for both in situ and remote monitoring of CCl 4 was made. It was concluded that resonance Raman could be used to detect these chemicals at levels of regulatory interest. Future effort directed towards the development of a suitable probe as well as a field-portable system would be desirable. Such effort could be directed towards the solution of a particular monitoring problem within a DOE waste remediation project. Once developed, however, it should be easily generalized to the analysis of other VOC's in other environments

Influence of Sensory Stimulation on Exhaled Volatile Organic Compounds.

Science.gov (United States)

Mazzatenta, A; Pokorski, M; Di Tano, A; Cacchio, M; Di Giulio, C

2016-01-01

The real-time exhaled volatile organic compounds (VOCs) have been suggested as a new biomarker to detect and monitor physiological processes in the respiratory system. The VOCs profile in exhaled breath reflects the biochemical alterations related to metabolic changes, organ failure, and neuronal activity, which are, at least in part, transmitted via the lungs to the alveolar exhaled breath. Breath analysis has been applied to investigate cancer, lung failure, and neurodegenerative diseases. There are by far no studies on the real-time monitoring of VOCs in sensory stimulation in healthy subjects. Therefore, in this study we investigated the breath parameters and exhaled VOCs in humans during sensory stimulation: smell, hearing, sight, and touch. Responses sensory stimulations were recorded in 12 volunteers using an iAQ-2000 sensor. We found significant effects of sensory stimulation. In particular, olfactory stimulation was the most effective stimulus that elicited the greatest VOCs variations in the exhaled breath. Since the olfactory pathway is distinctly driven by the hypothalamic and limbic circuitry, while other senses project first to the thalamic area and then re-project to other brain areas, the findings suggest the importance of olfaction and chemoreception in the regulation lung gas exchange. VOCs variations during sensory activation may become putative indicators of neural activity.

Solid anaerobic digestion batch with liquid digestate recirculation and wet anaerobic digestion of organic waste: Comparison of system performances and identification of microbial guilds.

Science.gov (United States)

Di Maria, Francesco; Barratta, Martino; Bianconi, Francesco; Placidi, Pisana; Passeri, Daniele

2017-01-01

Solid anaerobic digestion batch (SADB) with liquid digestate recirculation and wet anaerobic digestion of organic waste were experimentally investigated. SADB was operated at an organic loading rate (OLR) of 4.55kgVS/m 3 day, generating about 252NL CH 4 /kgVS, whereas the wet digester was operated at an OLR of 0.9kgVS/m 3 day, generating about 320NL CH 4 /kgVS. The initial total volatile fatty acids concentrations for SADB and wet digestion were about 12,500mg/L and 4500mg/L, respectively. There were higher concentrations of ammonium and COD for the SADB compared to the wet one. The genomic analysis performed by high throughput sequencing returned a number of sequences for each sample ranging from 110,619 to 373,307. More than 93% were assigned to the Bacteria domain. Seven and nine major phyla were sequenced for the SADB and wet digestion, respectively, with Bacteroidetes, Firmicutes and Proteobacteria being the dominant phyla in both digesters. Taxonomic profiles suggested a methanogenic pathway characterized by a relevant syntrophic acetate-oxidizing metabolism mainly in the liquid digestate of the SADB. This result also confirms the benefits of liquid digestate recirculation for improving the efficiency of AD performed with high solids (>30%w/w) content. Copyright © 2016 Elsevier Ltd. All rights reserved.

Crude glycerol combustion: Particulate, acrolein, and other volatile organic emissions

KAUST Repository

Steinmetz, Scott

2013-01-01

Crude glycerol is an abundant by-product of biodiesel production. As volumes of this potential waste grow, there is increasing interest in developing new value added uses. One possible use, as a boiler fuel for process heating, offers added advantages of energy integration and fossil fuel substitution. However, challenges to the use of crude glycerol as a boiler fuel include its low energy density, high viscosity, and high autoignition temperature. We have previously shown that a refractory-lined, high swirl burner can overcome challenges related to flame ignition and stability. However, critical issues related to ash behavior and the possible formation of acrolein remained. The work presented here indicates that the presence of dissolved catalysts used during the esterification and transesterification processes results in extremely large amounts of inorganic species in the crude glycerol. For the fuels examined here, the result is a submicron fly ash comprised primarily of sodium carbonates, phosphates, and sulfates. These particles report to a well-developed accumulation mode (0.3-0.7 μm diameter), indicating extensive ash vaporization and particle formation via nucleation, condensation, and coagulation. Particle mass emissions were between 2 and 4 g/m3. These results indicate that glycerol containing soluble catalyst is not suitable as a boiler fuel. Fortunately, process improvements are currently addressing this issue. Additionally, acrolein is of concern due to its toxicity, and is known to be formed from the low temperature thermal decomposition of glycerol. Currently, there is no known reliable method for measuring acrolein in sources. Acrolein and emissions of other volatile organic compounds were characterized through the use of a SUMMA canister-based sampling method followed by GC-MS analysis designed for ambient measurements. Results indicate crude glycerol combustion produces relatively small amounts of acrolein (∼15 ppbv) and other volatile organic

Volatile communication in plant-aphid interactions.

Science.gov (United States)

de Vos, Martin; Jander, Georg

2010-08-01

Volatile communication plays an important role in mediating the interactions between plants, aphids, and other organisms in the environment. In response to aphid infestation, many plants initiate indirect defenses through the release of volatiles that attract ladybugs, parasitoid wasps, and other aphid-consuming predators. Aphid-induced volatile release in the model plant Arabidopsis thaliana requires the jasmonate signaling pathway. Volatile release is also induced by infection with aphid-transmitted viruses. Consistent with mathematical models of optimal transmission, viruses that are acquired rapidly by aphids induce volatile release to attract migratory aphids, but discourage long-term aphid feeding. Although the ecology of these interactions is well-studied, further research is needed to identify the molecular basis of aphid-induced and virus-induced changes in plant volatile release. Copyright 2010 Elsevier Ltd. All rights reserved.

Method development for the determination of volatile organic compounds in mixed waste

International Nuclear Information System (INIS)

Sandoval, W.F.; Rogers, Y.C.; Schappert, M.F.; Boland, K.S.; Spall, W.D.; Wilkerson, C.W. Jr.

1993-01-01

While analytical methods exist for the determination of Resource Conservation and Recovery Act (RCRA) listed organic and inorganic compounds in hazardous materials, equivalent methods suitable for the characterization of radioactively contaminated samples are not at the same level of maturity. The Mixed Waste Methods Development Lab. has been established at Los Alamos National Lab. to address the need for such procedures. This presentation will focus on the efforts that have been directed toward the determination of volatile organic compounds (VOCs) in mixed waste matrices. The capabilities of the Mixed Waste Methods Development Lab. will be outlined. Modifications to the containment boxes and analytical instrumentation required for the analyses will be described, as will experimental procedures and system performance benchmarks. Preliminary results from surrogate and real mixed waste matrices will be presented, and future directions for our method development effort will be discussed

Liquid crystals for organic thin-film transistors

Science.gov (United States)

Iino, Hiroaki; Usui, Takayuki; Hanna, Jun-Ichi

2015-04-01

Crystalline thin films of organic semiconductors are a good candidate for field effect transistor (FET) materials in printed electronics. However, there are currently two main problems, which are associated with inhomogeneity and poor thermal durability of these films. Here we report that liquid crystalline materials exhibiting a highly ordered liquid crystal phase of smectic E (SmE) can solve both these problems. We design a SmE liquid crystalline material, 2-decyl-7-phenyl-[1]benzothieno[3,2-b][1]benzothiophene (Ph-BTBT-10), for FETs and synthesize it. This material provides uniform and molecularly flat polycrystalline thin films reproducibly when SmE precursor thin films are crystallized, and also exhibits high durability of films up to 200 °C. In addition, the mobility of FETs is dramatically enhanced by about one order of magnitude (over 10 cm2 V-1 s-1) after thermal annealing at 120 °C in bottom-gate-bottom-contact FETs. We anticipate the use of SmE liquid crystals in solution-processed FETs may help overcome upcoming difficulties with novel technologies for printed electronics.

Determination of volatile, phenolic, organic acid and sugar components in a Turkish cv. Dortyol (Citrus sinensis L. Osbeck) orange juice.

Science.gov (United States)

Kelebek, Hasim; Selli, Serkan

2011-08-15

Orange flavour is the results of a natural combination of volatile compounds in a well-balanced system including sugars, acids and phenolic compounds. This paper reports the results of the first determination of aroma, organic acids, sugars, and phenolic components in Dortyol yerli orange juices. A total of 58 volatile components, including esters (nine), terpenes (19), terpenols (13), aldehydes (two), ketones (three), alcohols (four) and acids (eight) were identified and quantified in Dortyol yerli orange juice by GC-FID and GC-MS. Organic acids, sugars and phenolic compositions were also determined by HPLC methods. The major organic acid and sugar found were citric acid and sucrose, respectively. With regard to phenolics, 14 compounds were identified and quantified in the orange juice. Terpenes and terpenols were found as the main types of volatile components in Dortyol yerli orange juice. In terms of aroma contribution to orange juice, 12 compounds were prominent based on the odour activity values (OAVs). The highest OAV values were recorded for ethyl butanoate, nootkatone, linalool and DL-limonene. When we compare the obtained results of cv. Dortyol orange juice with the other orange juice varieties, the composition of Dortyol orange juice was similar to Valencia and Navel orange juices. Copyright © 2011 Society of Chemical Industry.

Transport of Liquid Phase Organic Solutes in Liquid Crystalline Membranes

OpenAIRE

Han, Sangil

2010-01-01

Porous cellulose nitrate membranes were impregnated with 8CB and PCH5 LCs (liquid crystals) and separations of solutes dissolved in aqueous phases were performed while monitoring solute concentration via UV-VIS spectrometry. The diffusing organic solutes, which consist of one aromatic ring and various functional groups, were selected to exclude molecular size effects on the diffusion and sorption. We studied the effects on solute transport of solute intra-molecular hydrogen bonding and so...

Process engineering versus product engineering - A case study on volatile organic compounds removal

DEFF Research Database (Denmark)

Coutinho, João A.P.; Vilela, T.; Pereira, P.

2005-01-01

Three solutions for removing the dangerous volatile organic compound (VOC) xylene from an industrial coating process are presented and compared. Two of them are based on classical process engineering principles, i.e., development of separation-cleaning methods such as incineration and adsorption...... to the problem-need specified in the beginning of the project, but producing a novel formulation (chemical product design) represents a method that results to a completely xylene-free process which is environmentally and economically more interesting than those generated via the more traditional process...

Chirospecific analysis of plant volatiles

Energy Technology Data Exchange (ETDEWEB)

Tkachev, A V [N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation)

2007-10-31

Characteristic features of the analysis of plant volatiles by enantioselective gas (gas-liquid) chromatography and gas chromatography/mass spectrometry are discussed. The most recent advances in the design of enantioselective stationary phases are surveyed. Examples of the preparation of the most efficient phases based on modified cyclodextrins are given. Current knowledge on the successful analytical resolution of different types of plant volatiles (aliphatic and aromatic compounds and mono-, sesqui- and diterpene derivatives) into optical antipodes is systematically described. Chiral stationary phases used for these purposes, temperature conditions and enantiomer separation factors are summarised. Examples of the enantiomeric resolution of fragrance compounds and components of plant extracts, wines and essential oils are given.

Chirospecific analysis of plant volatiles

International Nuclear Information System (INIS)

Tkachev, A V

2007-01-01

Characteristic features of the analysis of plant volatiles by enantioselective gas (gas-liquid) chromatography and gas chromatography/mass spectrometry are discussed. The most recent advances in the design of enantioselective stationary phases are surveyed. Examples of the preparation of the most efficient phases based on modified cyclodextrins are given. Current knowledge on the successful analytical resolution of different types of plant volatiles (aliphatic and aromatic compounds and mono-, sesqui- and diterpene derivatives) into optical antipodes is systematically described. Chiral stationary phases used for these purposes, temperature conditions and enantiomer separation factors are summarised. Examples of the enantiomeric resolution of fragrance compounds and components of plant extracts, wines and essential oils are given.

The influence of surfactant on mass transfer coefficients in evaporation of volatile organic compound from water basin

Directory of Open Access Journals (Sweden)

Bunyakan, C.

2002-04-01

Full Text Available Volatile organic compounds (VOCs have been found in wastewater of many chemical industries. Evaporation of VOCs from open water basin in waste treatment facilities causes air-pollution and has been regulated in many countries. Reduction or prevention of VOCs evaporation from open water basin is then necessary. The aim of this research was to investigate the influence of surface film generated by an insoluble surfactant on the mass transfer coefficient of VOCs evaporating from water. Hexadecanol and octadecanol were used as surfactant in this investigation with the amount in the range of 0 to 35 μg/cm2 and 0 to 25 μg/cm2, respectively. The VOCs used in this study were methanol, acetone, methyl ethyl ketone and toluene. The experimental results showed that the surfactant film can reduce the gas film and liquid coefficients by 56 and 80 %, respectively. The suitable amounts of the surfactant were 25 μg/cm2 for hexadecanol and 15 μg/cm2 for octadecanol. From this investigation we can conclude that covering the water surface with a film of hexadecanol or octadecanol could significantly reduce the VOCs evaporation rate.Finally, the empirical equations correlating gas film and liquid film coefficient to amount of surfactants were developed and verified against the experimental data. The predicted values of the overall mass transfer coefficients, obtained by using these empirical equations, were in good agreement with the measured values. Thus the empirical equations of mass transfer coefficients developed in this work can be used to predict the evaporation rates of VOCs from water surface covered by hexadecanol or octadecanol film.

Türkiye Hisse Senedi Piyasasında Likidite Ölçülerinin Karşılaştırılması ve Likidite Volatilitesi Hisse Senedi Getirisi Arasındaki İlişki (Comparison of Liquidity Measures and The Relationship Between Volatility of Liquidity and Stock Returns in Turkish Stock Market

Directory of Open Access Journals (Sweden)

Cüneyt AKAR

2015-06-01

Full Text Available This paper aims to determine the relationship between stock returns and volatility of liquidity in Turkish Stock Market. It is also investigated whether various liquidity measures sort the stocks in the same way according to their liquidities. The data used in the study contains the closing prices, trading volumes and free floating of the stocks that are included in Borsa Istanbul 100 Index (BIST100 and covers the period from 28.02.2011 to 18.11.2014. Generalized Autoregressive Conditional Heteroscedasticity (GARCH and Autoregressive Moving Average models (ARMA are used to perform empirical analysis. According to the results, it can not be determined the clear significant relationship between stock returns and volatility of liquidity. Results also show that while stock size and Amihud illiquidity criteria sort the stocks in the same way, stock return standard deviation criterion produces different ranking.

Performance specifications for technology development: Application for characterization of volatile organic compounds in the environment

Energy Technology Data Exchange (ETDEWEB)

Carpenter, S.E.; Doskey, P.V.; Erickson, M.D.; Lindahl, P.C.

1994-07-01

This report contains information about technology development for the monitoring and remediation of environmental pollution caused by the release of volatile organic compounds. Topics discussed include: performance specification processes, gas chromatography, mass spectrometer, fiber-optic chemical sensors, infrared spectroscopy, Raman spectroscopy, piezoelectric sensors and electrochemical sensors. These methods are analyzed for their cost efficiency, accuracy, and the ability to meet the needs of the customer.

A New Class of Solvents for TRU Dissolution and Separation: Ionic Liquids. Project No. 81891

International Nuclear Information System (INIS)

Rogers, Robin D.

2004-01-01

Through the current EMSP funding, solvent extraction technologies based on liquid-liquid partitioning of TRU to an Ionic Liquid phase containing conventional complexants has been shown to be viable. The growing understanding of the role that the different components of an ionic liquid can have on the partitioning mechanism, and on the nature of the subsequent dissolved species indicates strongly that ionic liquids are not necessarily direct replacements for volatile or otherwise hazardous organic solvents. Separations and partitioning can be exceptionally complex with competing solvent extraction, cation, anion and sacrificial ion exchange mechanisms are all important, depending on the selection of components for formation of the ionic liquid phase, and that control of these competing mechanisms can be utilized to provide new, alternative separations schemes

The influence of temperature on the emission of volatile organic compounds from PVC flooring, carpet, and paint

NARCIS (Netherlands)

Wal, J.F. van der; Hoogeveen, A.W.; Wouda, P.

1997-01-01

The influence of temperature on the emission rate of volatile organic compounds (VOC) from four indoor materials was investigated in a small dynamic test chamber. The materials investigated were two carpets, a PVC flooring and a paint; the temperature range investigated was 23-50°C. The general

Concentrations and flux measurements of volatile organic compounds (VOC) in boreal forest soil

Science.gov (United States)

Mäki, Mari; Aaltonen, Hermanni; Heinonsalo, Jussi; Hellén, Heidi; Pumpanen, Jukka; Bäck, Jaana

2017-04-01

Volatile organic compounds (VOC) impact soil processes as VOCs transmit signals between roots and rhizosphere (Ditengou et al., 2015), VOCs can regulate microbial activity (Asensio et al., 2012), and VOCs can also promote root growth (Hung et al., 2012). Belowground concentrations of VOCs have not been measured in situ and for this reason, knowledge of how different soil organisms such as roots, rhizosphere and decomposers contribute to VOC production is limited. The aim of this study was to determine and quantify VOC fluxes and concentrations of different horizons from boreal forest soil. The VOC concentrations and fluxes were measured from Scots pine (Pinus sylvestris) forest soil at the SMEAR II station in southern Finland from 21th of April to 2nd of December in 2016. VOC fluxes were measured using dynamic (flow-through) chambers from five soil collars placed on five different locations. VOC concentrations were also measured in each location from four different soil horizons with the measurement depth 1-107 cm. VOCs were collected from underground gas collectors into the Tenax-Carbopack-B adsorbent tubes using portable pumps ( 100 ml min-1). The VOC concentrations and fluxes of isoprene, 11 monoterpenes, 13 sesquiterpenes and different oxygenated VOCs were measured. Sample tubes were analyzed using thermal desorption-gas chromatograph-mass spectrometry (TD-GC-MS). Soil temperature and soil water content were continuously monitored for each soil horizon. Our preliminary results show that the primary source of VOCs is organic soil layer and the contribution of mineral soil to the VOC formation is minor. VOC fluxes and concentrations were dominated by monoterpenes such as α-pinene, camphene, β-pinene, and Δ3-carene. Monoterpene concentration is almost 10-fold in organic soil compared to the deeper soil layers. However, the highest VOC fluxes on the soil surface were measured in October, whereas the monoterpene concentrations in organic soil were highest in July

Surface-enhanced Raman scattering (SERS)-based volatile organic compounds (VOCs) detection using plasmonic bimetallic nanogap substrate

DEFF Research Database (Denmark)

Wong, Chi Lok; Dinish, U. S.; Buddharaju, Kavitha Devi

2014-01-01

In this paper, we present surface-enhanced Raman scattering (SERS)-based volatile organic compounds (VOCs) detection with bimetallic nanogap structure substrate. Deep UV photolithography at the wavelength of 250 nm is used to pattern circular shape nanostructures. The nanogap between adjacent cir......-based VOCs detection platform for point-of-care breath analysis, homeland security, chemical sensing and environmental monitoring....

Wet effluent diffusion denuder technique and the determination of volatile organic compounds in air. II. Monoterpenes

Czech Academy of Sciences Publication Activity Database

Sklenská, Jana; Broškovičová, Anna; Večeřa, Zbyněk

2002-01-01

Roč. 973, 1-2 (2002), s. 211-216 ISSN 0021-9673 R&D Projects: GA ČR GA203/98/0943 Grant - others:SPSDII(XE) EV/02/11 Institutional research plan: CEZ:AV0Z4031919 Keywords : wet effluent denuder technique * volatile organic compounds * monoterpenes Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.098, year: 2002

Assessing soil ecotoxicity of methyl tert-butyl ether using earthworm bioassay; closed soil microcosm test for volatile organic compounds

International Nuclear Information System (INIS)

An, Youn-Joo

2005-01-01

An earthworm bioassay was conducted to assess ecotoxicity in methyl tert-butyl ether (MTBE)-amended soils. Ecotoxicity of MTBE to earthworms was evaluated by a paper contact method, natural field soil test, and an OECD artificial soil test. All tests were conducted in closed systems to prevent volatilization of MTBE out of test units. Test earthworm species were Perionyx excavatus and Eisenia andrei. Mortality and abnormal morphology of earthworms exposed to different concentrations of MTBE were examined. MTBE was toxic to both earthworm species and the severity of response increased with increasing MTBE concentrations. Perionyx excavatus was more sensitive to MTBE than Eisenia andrei in filter papers and two different types of soils. MTBE toxicity was more severe in OECD artificial soils than in field soils, possibly due to the burrowing behavior of earthworms into artificial soils. The present study demonstrated that ecotoxicity of volatile organic compounds such as MTBE can be assessed using an earthworm bioassay in closed soil microcosm with short-term exposure duration. - Earthworm bioassay can be a good protocol to assess soil ecotoxicity of volatile organic compounds such as MTBE

Determination of volatile organic compounds responsible for flavour in cooked river buffalo meat

Directory of Open Access Journals (Sweden)

A. Di Luccia

2010-02-01

Full Text Available Flavour is an important consumer attractive that directly influences the success of food products on the market. The determination of odorous molecules and their identification allows to useful knowledge for producers to valorise their own products. Buffalo meat has a different chemical composition from pork and beef and requires some cautions in cooking and processing. This work aims at the identification of volatile molecules responsible for flavours in river buffalo meat. The determination was carried out by solid phase micro-extraction (SPME technique and analysed by gas chromatography coupled to mass spectrometry (GC-MS. The most relevant results were the higher odorous impact of buffalo meat and the higher content of sulphide compounds responsible for wild aroma respect to pork and beef. These results were obtained comparing the total area of peaks detected in every chromatogram. We have also found significant differences concerning the contents of pentadecane, 1-hexanol-2 ethyl, butanoic acid, furano-2-penthyl. The origin of volatile organic compounds and their influence on the river buffalo aromas were discussed.

Analysis of a gas-liquid film plasma reactor for organic compound oxidation

Energy Technology Data Exchange (ETDEWEB)

Hsieh, Kevin [Department of Chemical and Biomedical Engineering, Florida State University, Tallahassee, FL 32310 (United States); Wang, Huijuan [School of Environmental and Safety Engineering, Jiangsu University, Zhenjiang 212013 (China); Locke, Bruce R., E-mail: blocke@fsu.edu [Department of Chemical and Biomedical Engineering, Florida State University, Tallahassee, FL 32310 (United States)

2016-11-05

Highlights: • Non-homogeneous filamentary plasma discharge formed along gas-liquid interface. • Hydrogen peroxide formed near interface favored over organic oxidation from liquid. • Post-plasma Fenton reactions lead to complete utilization of hydrogen peroxide. - Abstract: A pulsed electrical discharge plasma formed in a tubular reactor with flowing argon carrier gas and a liquid water film was analyzed using methylene blue as a liquid phase hydroxyl radical scavenger and simultaneous measurements of hydrogen peroxide formation. The effects of liquid flow rate, liquid conductivity, concentration of dye, and the addition of ferrous ion on dye decoloration and degradation were determined. Higher liquid flow rates and concentrations of dye resulted in less decoloration percentages and hydrogen peroxide formation due to initial liquid conductivity effects and lower residence times in the reactor. The highest decoloration energy yield of dye found in these studies was 5.2 g/kWh when using the higher liquid flow rate and adding the catalyst. The non-homogeneous nature of the plasma discharge favors the production of hydrogen peroxide in the plasma-liquid interface over the chemical oxidation of the organic in the bulk liquid phase and post-plasma reactions with the Fenton catalyst lead to complete utilization of the plasma-formed hydrogen peroxide.

Accurate Measurement of the Optical Constants n and k for a Series of 57 Inorganic and Organic Liquids for Optical Modeling and Detection.

Science.gov (United States)

Myers, Tanya L; Tonkyn, Russell G; Danby, Tyler O; Taubman, Matthew S; Bernacki, Bruce E; Birnbaum, Jerome C; Sharpe, Steven W; Johnson, Timothy J

2018-04-01

For optical modeling and other purposes, we have created a library of 57 liquids for which we have measured the complex optical constants n and k. These liquids vary in their nature, ranging in properties that include chemical structure, optical band strength, volatility, and viscosity. By obtaining the optical constants, one can model most optical phenomena in media and at interfaces including reflection, refraction, and dispersion. Based on the works of others, we have developed improved protocols using multiple path lengths to determine the optical constants n/k for dozens of liquids, including inorganic, organic, and organophosphorus compounds. Detailed descriptions of the measurement and data reduction protocols are discussed; agreement of the derived optical constant n and k values with literature values are presented. We also present results using the n/k values as applied to an optical modeling scenario whereby the derived data are presented and tested for models of 1 µm and 100 µm layers for dimethyl methylphosphonate (DMMP) on both metal (aluminum) and dielectric (soda lime glass) substrates to show substantial differences between the reflected signal from highly reflective substrates and less-reflective substrates.

Adsorptive performance of chromium-containing ordered mesoporous silica on volatile organic compounds (VOCs

Directory of Open Access Journals (Sweden)

Jianwei Fan

2017-09-01

Full Text Available Volatile organic compounds (VOCs are the primary poisonous emissions into the atmosphere in natural gas exploitation and disposing process. The adsorption method has been widely applied in actual production because of its good features such as low cost, low energy consumption, flexible devices needed, etc. The commonly used adsorbents like activated carbon, silicon molecular sieves and so on are not only susceptible to plugging or spontaneous combustion but difficult to be recycled. In view of this, a new adsorbent (CrSBA15 was made by the co-assembly method to synthesize the ordered mesoporous silica materials with different amounts of chromium to eliminate VOCs. This new adsorbent was characterized by small-angle-X-ray scattering (SAXS, nitrogen adsorption/desorption, scanning electron microscopy (SEM, and transmission electron microscopy (TEM. Its adsorption performance to eliminate VOCs (toluene, benzene, cyclohexane and ethyl acetate used as typical pollutants was also tested systematically. Research results indicate that this new adsorbent of CrSBA-15(30, with the silicon/chromium ration being 30, owns the maximum micropore volume, and shows a higher adsorption performance in eliminating toluene, benzene, cyclohexane and ethyl acetate. Besides, it is cost-effective and much easier to be recycled than the activated carbon. In conclusion, CrSBA-15(30 is a good adsorbent to eliminate VOCs with broad application prospects. Keywords: Mesoporous materials, Silicon dioxide, Synthesis, Adsorption, Volatile organic compounds (VOCs, Recyclability, Energy saving

Networks of volatility spillovers among stock markets

Science.gov (United States)

Baumöhl, Eduard; Kočenda, Evžen; Lyócsa, Štefan; Výrost, Tomáš

2018-01-01

In our network analysis of 40 developed, emerging and frontier stock markets during the 2006-2014 period, we describe and model volatility spillovers during both the global financial crisis and tranquil periods. The resulting market interconnectedness is depicted by fitting a spatial model incorporating several exogenous characteristics. We document the presence of significant temporal proximity effects between markets and somewhat weaker temporal effects with regard to the US equity market - volatility spillovers decrease when markets are characterized by greater temporal proximity. Volatility spillovers also present a high degree of interconnectedness, which is measured by high spatial autocorrelation. This finding is confirmed by spatial regression models showing that indirect effects are much stronger than direct effects; i.e., market-related changes in 'neighboring' markets (within a network) affect volatility spillovers more than changes in the given market alone, suggesting that spatial effects simply cannot be ignored when modeling stock market relationships. Our results also link spillovers of escalating magnitude with increasing market size, market liquidity and economic openness.

Symptoms of mothers and infants related to total volatile organic compounds in household products

OpenAIRE

Farrow, A; Taylor, H; Northstone, K; Golding, J

2003-01-01

The authors sought to determine whether reported symptoms of mothers and infants were associated significantly with the use of household products that raised indoor levels of total volatile organic compounds (TVOCs). Data collected from 170 homes within the Avon Longitudinal Study of Parents and Children (ALSPAC: a large birth cohort of more than 10,000) had determined which household products were associated with the highest levels of TVOCs. The latter data were collected over a period that ...

Use of solid phase microextraction to identify volatile organic compounds in brazilian wines from different grape varieties

Directory of Open Access Journals (Sweden)

Natália Cristina Morais Fernandes

Full Text Available Abstract The Brazilian wine industry has shown significant growth in recent years and the insertion of new concepts, such as geographical indications as signs of quality, has placed Brazil in tune with the tendencies of world wine production. The aim of this work was to apply the Solid Phase Microextraction technique in combination with Gas Chromatography-Mass Spectrometry to study Brazilian wines made from different grape varieties, in order to separate and identify their volatile organic compounds. These substances were identified by comparisons between the spectra obtained with those presented in the NIST library database, and by comparisons with linear retention indices and literature data. The amounts of the compounds were calculated based on the total peak areas of the chromatograms. Forty-seven volatile compounds were identified and grouped into alcohols, aldehydes, fatty acids, esters, hydrocarbons, ketones and terpenes. Most of them belonged to the ester function, conferring a fruity aroma on the wines. The alcohols may have originated from the yeast metabolism, contributing to the alcoholic and floral aromas. Ethyl lactate, 1-hexanol and diethyl maleate were identified in all the varieties, except Merlot. Decanal, methyl citronellate, (E-2-hexenyl-3-methylbutyrate were only found in Merlot, while 2,3-butanediol was only present in the Tannat wines. 2-Phenylethanol was present in all varieties and is recognized as giving pleasant rose and honey attributes to wines. This study showed that the volatile profile of red wines is mainly characterized by esters and higher alcohols. The statistical analysis of the comparison of averages showed a greater amount of averages significantly different in the relative areas of Merlot wine. The Principal Component Analysis showed one grouping composed only of the Merlot wine samples, and this was probably related to the existence of the volatile organic compounds that were specifically identified in

Direct analysis of volatile organic compounds in foods by headspace extraction atmospheric pressure chemical ionisation mass spectrometry.

Science.gov (United States)

Perez-Hurtado, P; Palmer, E; Owen, T; Aldcroft, C; Allen, M H; Jones, J; Creaser, C S; Lindley, M R; Turner, M A; Reynolds, J C

2017-11-30

The rapid screening of volatile organic compounds (VOCs) by direct analysis has potential applications in the areas of food and flavour science. Currently, the technique of choice for VOC analysis is gas chromatography/mass spectrometry (GC/MS). However, the long chromatographic run times and elaborate sample preparation associated with this technique have led a movement towards direct analysis techniques, such as selected ion flow tube mass spectrometry (SIFT-MS), proton transfer reaction mass spectrometry (PTR-MS) and electronic noses. The work presented here describes the design and construction of a Venturi jet-pump-based modification for a compact mass spectrometer which enables the direct introduction of volatiles for qualitative and quantitative analysis. Volatile organic compounds were extracted from the headspace of heated vials into the atmospheric pressure chemical ionization source of a quadrupole mass spectrometer using a Venturi pump. Samples were analysed directly with no prior sample preparation. Principal component analysis (PCA) was used to differentiate between different classes of samples. The interface is shown to be able to routinely detect problem analytes such as fatty acids and biogenic amines without the requirement of a derivatisation step, and is shown to be able to discriminate between four different varieties of cheese with good intra and inter-day reproducibility using an unsupervised PCA model. Quantitative analysis is demonstrated using indole standards with limits of detection and quantification of 0.395 μg/mL and 1.316 μg/mL, respectively. The described methodology can routinely detect highly reactive analytes such as volatile fatty acids and diamines without the need for a derivatisation step or lengthy chromatographic separations. The capability of the system was demonstrated by discriminating between different varieties of cheese and monitoring the spoilage of meats. © 2017 The Authors. Rapid Communications in Mass

A New Prediction Method for Organic Liquids Sorption into Polymers

Czech Academy of Sciences Publication Activity Database

Randová, A.; Bartovská, L.; Izák, Pavel; Friess, K.

2015-01-01

Roč. 475, FEB 1 (2015), s. 545-551 ISSN 0376-7388 R&D Projects: GA ČR(CZ) GAP106/12/0569; GA MŠk(CZ) LD14094 Institutional support: RVO:67985858 Keywords : organic liquids * liquid non-solvents * polymers Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 5.557, year: 2015

Lime treatment of liquid waste containing heavy metals, radionuclides and organics

International Nuclear Information System (INIS)

DuPont, A.

1990-01-01

This paper reports on lime treatment of liquid waste containing heavy metals, radio nuclides and organics. Lime is wellknown for its use in softening drinking water the treatment of municipal wastewaters. It is becoming important in the treatment of industrial wastewater and liquid inorganic hazardous waste; however, there are many questions regarding the use of lime for the treatment of liquid hazardous waste

Treatment and conditioning of radioactive organic liquids

International Nuclear Information System (INIS)

1992-07-01

Liquid organic radioactive wastes are generated from the use of radioisotopes in nuclear research centres and in medical and industrial applications. The volume of these wastes is small by comparison with aqueous radioactive wastes, for example; nevertheless, a strategy for the effective management of these wastes is necessary in order to ensure their safe handling, processing, storage and disposal. A aqueous radioactive wastes may be discharged to the environment after the radioactivity has decayed or been removed. By contrast, organic radioactive wastes require management steps that not only take account of their radioactivity, but also of their chemical content. This is because both the radioactivity and the organic chemical nature can have detrimental effects on health and the environment. Liquid radioactive wastes from these applications typically include vacuum pump oil, lubricating oil and hydraulic fluids, scintillation cocktails from analytical laboratories, solvents from solvent extraction research and uranium refining, and miscellaneous organic solvents. The report describes the factors which should be considered in the development of appropriate strategies for managing this class of wastes from generation to final disposal. Waste sources and characterization, treatment and conditioning processes, packaging, interim storage and the required quality assurance are all discussed. The report is intended to provide guidance to developing Member States which do not have nuclear power generation. A range of processes and procedures is presented, though emphasis is given to simple, easy-to-operate processes requiring less sophisticated and relatively inexpensive equipment. 31 refs, 16 figs, 3 tabs

Research on organic liquids as reactor coolants. Status report from Hungary

International Nuclear Information System (INIS)

Kiss, I.

1967-01-01

The organic-moderated and cooled nuclear reactor concept has stimulated extensive activities in numerous different areas of research. Investigations started in Hungary in 1958 do not cover all topics of interest in organic reactors and so far no projects have been started to build such a reactor. Since OMRE and other organic reactor experiments have already shown the potential use of organic materials as reactor coolants and moderators, efforts have been focused rather on the investigation and solution of certain specific particular problems and also on economic aspects. One of the most important objectives seems to be a better knowledge of the radiolytic heat transfer and neutron physics behaviour of organic liquids. In Hungary the following topics were selected for investigation: Radiation stability of organic compounds and their mixtures; Heat-transfer studies; Investigations on the moderating parameters of organic liquids; Economic analysis of the possible use of organic reactors for process heat application

Research on organic liquids as reactor coolants. Status report from Hungary

Energy Technology Data Exchange (ETDEWEB)

Kiss, I [Central Research Institute for Physics, Budapest (Hungary)

1967-01-01

The organic-moderated and cooled nuclear reactor concept has stimulated extensive activities in numerous different areas of research. Investigations started in Hungary in 1958 do not cover all topics of interest in organic reactors and so far no projects have been started to build such a reactor. Since OMRE and other organic reactor experiments have already shown the potential use of organic materials as reactor coolants and moderators, efforts have been focused rather on the investigation and solution of certain specific particular problems and also on economic aspects. One of the most important objectives seems to be a better knowledge of the radiolytic heat transfer and neutron physics behaviour of organic liquids. In Hungary the following topics were selected for investigation: Radiation stability of organic compounds and their mixtures; Heat-transfer studies; Investigations on the moderating parameters of organic liquids; Economic analysis of the possible use of organic reactors for process heat application.

Detection of Volatile Organic Compound Gas Using Localized Surface Plasmon Resonance of Gold Nanoparticles

International Nuclear Information System (INIS)

Sri Nengsih; Akrajas Ali Umar; Muhamad Mat Salleh; Muhammad Yahaya

2011-01-01

This paper reports on the detection of several organic vapors using the unique characteristic of localized surface plasmon resonance (LSPR) gold nanoparticles. Gold nanoparticles on quartz substrate were prepared using seed mediated growth method. In a typical process, gold nanoparticles with average size ca. 36 nm were obtained to densely grown on the substrate. Detection of gas was based on the change in the LSPR of the gold nanoparticles film upon the exposure to the gas sample. It was found that gold nanoparticles were sensitive to the presence of volatile organic compound (VOC) gas from the change in the surface plasmon resonance (SPR) intensity. The mechanism for the detection of VOCs gas will be discussed. (author)

Ammonia volatilization from sows on grassland

Science.gov (United States)

Sommer, S. G.; Søgaard, H. T.; Møller, H. B.; Morsing, S.

According to regulations, sows with piglets on organic farms must graze on pastures. Volatilization of ammonia (NH 3) from urine patches may represent a significant source of nitrogen (N) loss from these farms. Inputs of N are low on organic farms and losses may reduce crop production. This study examined spatial variations in NH 3 volatilization using a movable dynamic chamber, and the pH and total ammoniacal nitrogen (TAN) content in the topsoil of pastures with grazing sows was measured during five periods between June 1998 and May 1999. Gross NH 3 volatilization from the pastures was also measured with an atmospheric mass balance technique during seven periods from September 1997 until June 1999. The dynamic chamber study showed a high variation in NH 3 volatilization because of the distribution of urine; losses were between 0 and 2.8 g NH 3-N m -2 day -1. Volatilization was highest near the feeding area and the huts, where the sows tended to urinate. Ammonia volatilization rate was linearly related to the product of NH 3 concentration in the boundary layer and wind speed. The NH 3 in the boundary layer was in equilibrium with NH 3 in soil solution. Gross NH 3 volatilization was in the range 0.07-2.1 kg NH 3-N ha -1 day -1 from a pasture with 24 sows ha -1. Ammonia volatilization was related to the amount of feed given to the sows, incident solar radiation and air temperature during measuring periods, and also to temperature, incident solar radiation and rain 1-2 days before measurements. Annual ammonia loss was 4.8 kg NH 3-N sow -1.

Measurements of oxygenated volatile organic compounds in the oil sands region of Alberta

Science.gov (United States)

Moussa, S. G.; Leithead, A.; Li, S. M.; Gordon, M.; Hayden, K. L.; Wang, D. K.; Staebler, R. M.; Liu, P.; O'Brien, J.; Mittermeier, R.; Liggio, J.

2014-12-01

Oxygenated volatile organic compounds (OVOCs) are ubiquitous in the atmosphere, and represent an important fraction of volatile organic compounds. Additionally some OVOC species may pose health risks. OVOCs can affect the oxidative and radiative budget of the atmosphere since they are precursors to ground level ozone, hydroxyl radicals and secondary organic aerosols (SOA). OVOCs such as methanol, formaldehyde, acetaldehyde, acetone, crotonaldehyde, methylvinylketone (MVK), methylethylketone (MEK) and acrolein can be emitted from anthropogenic and biogenic sources. Additionally, they are the secondary products of the photo-oxidation of hydrocarbons (biogenic and anthropogenic). Understanding the magnitude of these sources is a prerequisite for accurate representations of radical cycling, ozone production and SOA formation in air quality models. The sources of OVOCs in the Alberta Oil Sands (OS) region have not previously been well characterized. In the summer of 2013, airborne measurements of various OVOCs were made in the Athabasca oil sands region between August 13 and September 7, 2013. Proton Transfer Reaction-Time of Flight-Mass Spectrometry (PTR-ToF-MS) was used to measure methanol, formaldehyde, acetaldehyde, acetone, crotonaldehyde, MVK, MEK, acrolein as well as other hydrocarbons. Emission ratios (ER) for several OVOCs (relative to carbon monoxide; CO) were used to estimate direct anthropogenic emissions from OS industrial sources, while the calculated OH radical exposures were used to estimate the production and removal of secondary anthropogenic OVOCs. The results indicate that OVOCs such as acetaldehyde, crotonaldehyde and MVK have both primary and secondary anthropogenic and biogenic sources. However, species such as methanol and acrolein are from biogenic and anthropogenic sources, respectively. The results of this work will help to characterize sources of OVOCs and the factors influencing their atmospheric fate in the Oil Sands region.

Liquid phase oxidation via heterogeneous catalysis organic synthesis and industrial applications

CERN Document Server

Clerici, Mario G

2013-01-01

Sets the stage for environmentally friendly industrial organic syntheses From basic principles to new and emerging industrial applications, this book offers comprehensive coverage of heterogeneous liquid-phase selective oxidation catalysis. It fully examines the synthesis, characterization, and application of catalytic materials for environmentally friendly organic syntheses. Readers will find coverage of all the important classes of catalysts, with an emphasis on their stability and reusability. Liquid Phase Oxidation via Heterogeneous Catalysis features contributions from an internation

Systemic resistance induced by volatile organic compounds emitted by plant growth-promoting fungi in Arabidopsis thaliana.

Directory of Open Access Journals (Sweden)

Hushna Ara Naznin

Full Text Available Volatile organic compounds (VOC were extracted and identified from plant growth-promoting fungi (PGPF, Phoma sp., Cladosporium sp. and Ampelomyces sp., using gas chromatography-mass spectrometry (GC-MS. Among the three VOC extracted, two VOC blends (emitted from Ampelomyces sp. and Cladosporium sp. significantly reduced disease severity in Arabidopsis plants against Pseudomonas syringae pv. tomato DC3000 (Pst. Subsequently, m-cresol and methyl benzoate (MeBA were identified as major active volatile compounds from Ampelomyces sp. and Cladosporium sp., respectively, and found to elicit induced systemic resistance (ISR against the pathogen. Molecular signaling for disease suppression by the VOC were investigated by treating different mutants and transgenic Arabidopsis plants impaired in salicylic acid (SA or Jasmonic acid (JA/ethylene (ET signaling pathways with m-cresol and MeBA followed by challenge inoculation with Pst. Results show that the level of protection was significantly lower when JA/ET-impaired mutants were treated with MeBA, and in SA-, and JA/ET-disrupted mutants after m-cresol treatment, indicating the involvement of these signal transduction pathways in the ISR primed by the volatiles. Analysis of defense-related genes by real-time qRT-PCR showed that both the SA-and JA-signaling pathways combine in the m-cresol signaling of ISR, whereas MeBA is mainly involved in the JA-signaling pathway with partial recruitment of SA-signals. The ET-signaling pathway was not employed in ISR by the volatiles. Therefore, this study identified two novel volatile components capable of eliciting ISR that may be promising candidates in biological control strategy to protect plants from diseases.

Cereal crop volatile organic compound induction after mechanical injury, beetle herbivory (Oulema spp.), or fungal infection (Fusarium spp.)

Science.gov (United States)

Herbivory, mechanical injury or pathogen infestation to vegetative tissues can induce volatile organic compounds (VOCs) production, which can provide defensive functions to injured and uninjured plants. In our studies with ‘McNeal’ wheat, ‘Otana’ oat, and ‘Harrington’ barley, plants that were mechan...

Rapid recognition of volatile organic compounds with colorimetric sensor arrays for lung cancer screening.

Science.gov (United States)

Zhong, Xianhua; Li, Dan; Du, Wei; Yan, Mengqiu; Wang, You; Huo, Danqun; Hou, Changjun

2018-06-01

Volatile organic compounds (VOCs) in breath can be used as biomarkers to identify early stages of lung cancer. Herein, we report a disposable colorimetric array that has been constructed from diverse chemo-responsive colorants. Distinguishable difference maps were plotted within 4 min for specifically targeted VOCs. Through the consideration of various chemical interactions with VOCs, the arrays successfully discriminate between 20 different volatile organic compounds in breath that are related to lung cancer. VOCs were identified either with the visualized difference maps or through pattern recognition with an accuracy of at least 90%. No uncertainties or errors were observed in the hierarchical cluster analysis (HCA). Finally, good reproducibility and stability of the array was achieved against changes in humidity. Generally, this work provides fundamental support for construction of simple and rapid VOC sensors. More importantly, this approach provides a hypothesis-free array method for breath testing via VOC profiling. Therefore, this small, rapid, non-invasive, inexpensive, and visualized sensor array is a powerful and promising tool for early screening of lung cancer. Graphical abstract A disposable colorimetric array has been developed with broadly chemo-responsive dyes to incorporate various chemical interactions, through which the arrays successfully discriminate 20 VOCs that are related to lung cancer via difference maps alone or chemometrics within 4 min. The hydrophobic porous matrix provides good stability against changes in humidity.

Fourier Spot Volatility Estimator: Asymptotic Normality and Efficiency with Liquid and Illiquid High-Frequency Data

Science.gov (United States)

2015-01-01

The recent availability of high frequency data has permitted more efficient ways of computing volatility. However, estimation of volatility from asset price observations is challenging because observed high frequency data are generally affected by noise-microstructure effects. We address this issue by using the Fourier estimator of instantaneous volatility introduced in Malliavin and Mancino 2002. We prove a central limit theorem for this estimator with optimal rate and asymptotic variance. An extensive simulation study shows the accuracy of the spot volatility estimates obtained using the Fourier estimator and its robustness even in the presence of different microstructure noise specifications. An empirical analysis on high frequency data (U.S. S&P500 and FIB 30 indices) illustrates how the Fourier spot volatility estimates can be successfully used to study intraday variations of volatility and to predict intraday Value at Risk. PMID:26421617

Organic liquids-responsive β-cyclodextrin-functionalized graphene-based fluorescence probe: label-free selective detection of tetrahydrofuran.

Science.gov (United States)

Hu, Huawen; Xin, John H; Hu, Hong; Wang, Xiaowen; Lu, Xinkun

2014-06-06

In this study, a label-free graphene-based fluorescence probe used for detection of volatile organic liquids was fabricated by a simple, efficient and low-cost method. To fabricate the probe, a bio-based β-cyclodextrin (β-CD) was firstly grafted on reduced graphene surfaces effectively and uniformly, as evidenced by various characterization techniques such as Ultraviolet/Visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, scanning electron microscopy and transmission electron microscopy. The subsequent inclusion of Rhodamine B (RhB) into the inner cavities of the β-CD grafted on the graphene surfaces was achieved easily by a solution mixing method, which yielded the graphene-based fluorescent switch-on probe. In addition, the gradual and controllable quenching of RhB by Fluorescence Resonance Energy Transfer from RhB to graphene during the process of stepwise accommodation of the RhB molecules into the β-CD-functionalized graphene was investigated in depth. A wide range of organic solvents was examined using the as-fabricated fluorescence probe, which revealed the highest sensitivity to tetrahydrofuran with the detection limit of about 1.7 μg/mL. Some insight into the mechanism of the different responsive behaviors of the fluorescence sensor to the examined targets was also described.

Organic Liquids-Responsive β-Cyclodextrin-Functionalized Graphene-Based Fluorescence Probe: Label-Free Selective Detection of Tetrahydrofuran

Directory of Open Access Journals (Sweden)

Huawen Hu

2014-06-01

Full Text Available In this study, a label-free graphene-based fluorescence probe used for detection of volatile organic liquids was fabricated by a simple, efficient and low-cost method. To fabricate the probe, a bio-based β-cyclodextrin (β-CD was firstly grafted on reduced graphene surfaces effectively and uniformly, as evidenced by various characterization techniques such as Ultraviolet/Visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, scanning electron microscopy and transmission electron microscopy. The subsequent inclusion of Rhodamine B (RhB into the inner cavities of the β-CD grafted on the graphene surfaces was achieved easily by a solution mixing method, which yielded the graphene-based fluorescent switch-on probe. In addition, the gradual and controllable quenching of RhB by Fluorescence Resonance Energy Transfer from RhB to graphene during the process of stepwise accommodation of the RhB molecules into the β-CD-functionalized graphene was investigated in depth. A wide range of organic solvents was examined using the as-fabricated fluorescence probe, which revealed the highest sensitivity to tetrahydrofuran with the detection limit of about 1.7 μg/mL. Some insight into the mechanism of the different responsive behaviors of the fluorescence sensor to the examined targets was also described.

Volatilization and Thermal Decomposition Mechanisms of Room-Temperature Ionic Liquids (PRE-PRINT)

Science.gov (United States)

2017-03-07

silica nanoparticles for quasi-solid-state dye-sensitized solar cells.” J. Am. Chem. Soc. 125, 1166-1167 (2003). 11. Wang, P. et al. “ Charge ...currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) 2. REPORT TYPE Technical Paper 3...organic compounds (VOCs) used as industrial solvents with involatile liquids. RTILs also show promise for applications in fuel cells, batteries, solar

Direct ecosystem fluxes of volatile organic compounds from oil palms in South-East Asia

OpenAIRE

P. K. Misztal; E. Nemitz; B. Langford; C. F. Di Marco; G. J. Phillips; C. N. Hewitt; A. R. MacKenzie; S. M. Owen; D. Fowler; M. R. Heal; J. N. Cape

2011-01-01

This paper reports the first direct eddy covariance fluxes of reactive biogenic volatile organic compounds (BVOCs) from oil palms to the atmosphere using proton-transfer-reaction mass spectrometry (PTR-MS), measured at a plantation in Malaysian Borneo. At midday, net isoprene flux constituted the largest fraction (84 %) of all emitted BVOCs measured, at up to 30 mg m⁻² h⁻¹ over 12 days. By contrast, the sum of its oxidation products methyl vinyl k...