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1

Tribological characteristics of magnesium alloy using N-containing compounds as lubricating additives during sliding  

Microsoft Academic Search

The tribological characteristics of a magnesium alloy, AZ91D, were investigated in a sliding lubricating system using various N-containing compounds as lubricating additives on a Timken type tester against a bearing steel (AISI52100) ring. Results indicated that a significant improvement in the tribological performance exists using N-containing compounds as additives. The characteristics of anti-wear, anti friction and load-carrying capacity increased with

Weijiu Huang; Changhua Du; Zhaofeng Li; Ming Liu; Weiming Liu

2006-01-01

2

Organic Compounds Database  

NSDL National Science Digital Library

The Colby College Department of Chemistry offers the Organic Compounds Database, which was compiled by Harold Bell of the Virginia Polytechnic Institute. Visitors can search by the compounds melting point, boiling point, index of refraction, molecular weight, formula, absorption wavelength, mass spectral peak, chemical type, and by partial name. Once entered, results are returned with basically the same type of information that can be searched, plus any other critical information. References are provided for the close to 2500 organic compounds included in the database; yet, because the site was last modified in 1995, varying the data may be required to fully authenticate its accuracy.

Bell, Harold M.

2000-01-01

3

SAMPLING FOR ORGANIC COMPOUNDS  

EPA Science Inventory

The methods of sampling ambient air for organic compounds for subsequent analysis are discussed. The following methods of sample collection are presented and the advantages and disadvantages of each is given: concentration of component of interest on to solid sorbents, into liqui...

4

Organic Compounds in Carbonaceous Meteorites.  

National Technical Information Service (NTIS)

Carbonaceous meteorites are relatively enriched in soluble organic compounds. To date, these compounds provide the only record available to study a range of organic chemical processes in the early Solar System chemistry. The Murchison meteorite is the bes...

G. Cooper

2001-01-01

5

(Energies of organic compounds)  

Microsoft Academic Search

The first part of our study of the enthalpy of reduction of carbonyl compounds has been completed and includes four aldehydes, acetone, a series of cyclic ketones and ethyl acetate. The results suggest that some of the literature data for these compounds are significantly in error. Equilibrium constants have been measured for the reaction of carbonyl compounds with water to

Wiberg

1989-01-01

6

Thermodynamics of organic compounds  

Microsoft Academic Search

Basic and applied research have continued on the thermodynamic properties of currently used high density\\/high energy fuels and of pure chemical compounds that may be constituents of high energy fuels of the future. Enthalpy of combustion was measured for three compounds that are constituents of current ramjet fuels--hexacyclic exo, exo-dihydrodinorbornadiene, hexacyclic endo, endo-dihydrodinorbornadiene and exo-tetrahydrodicyclopentadiene (JP-10). Heat capacities of exo-tetrahydrodicyclopentadiene

W. D. Good; R. H. P. Thomas; B. E. Gammon; S. Lee-Bechtold; J. E. Callanan; N. K. Smith

1980-01-01

7

Thermodynamics of organic compounds  

NASA Astrophysics Data System (ADS)

Basic and applied research have been continued on the thermodynamic properties of currently used high density/high energy fuels and of pure chemical compounds that may be constituents of high energy fuels of the future. Enthalpy of combustion was measured for three compounds that are constituents of current ramjet fuels--hexacyclic exo, exo-dihydrodinorbornadiene, hexacyclic endo, endo-dihydrodinorbornadiene and exo-tetrahydrodicyclocpentadiene (JP-10). Heat capacities of exo-tetrahydrodicyclopentadiene (JP-10) and RJ-6, a blend of JP-10 and the hydrogenated dimers of norbornadiene, were measured by differential scanning calorimetry. Enthalpy of combustion was measured for two pure hydrocarbons, 1,7-dimethylindan and 1,4-dimethyl-2-isobutylbenzene, that are expected to have high steric interaction energies of alkyl substituents in the ring structure, and measurements are in progress on 1-ethyl-8-methylnaphthalene and 1,6-dimethylindan.

Good, W. D.; Smith, N. K.; Thomas, R. H. P.; Gammon, B. E.; Lee-Bechtold, S.

1980-09-01

8

Photochemical dimerization of organic compounds  

DOEpatents

At least one of selectivity and reaction rate of photosensitized vapor phase dimerizations, including dehydrodimerizations, hydrodimerizations and cross-dimerizations of saturated and unsaturated organic compounds is improved by conducting the dimerization in the presence of hydrogen or nitrous oxide.

Crabtree, Robert H. (Bethany, CT); Brown, Stephen H. (Princeton, NJ); Muedas, Cesar A. (New Haven, CT); Ferguson, Richard R. (Branford, CT)

1992-01-01

9

Biomedical Compounds from Marine organisms  

PubMed Central

The Ocean, which is called the ‘mother of origin of life’, is also the source of structurally unique natural products that are mainly accumulated in living organisms. Several of these compounds show pharmacological activities and are helpful for the invention and discovery of bioactive compounds, primarily for deadly diseases like cancer, acquired immuno-deficiency syndrome (AIDS), arthritis, etc., while other compounds have been developed as analgesics or to treat inflammation, etc. The life-saving drugs are mainly found abundantly in microorganisms, algae and invertebrates, while they are scarce in vertebrates. Modern technologies have opened vast areas of research for the extraction of biomedical compounds from oceans and seas.

Jha, Rajeev Kumar; Zi-rong, Xu

2004-01-01

10

Extraterrestrial Organic Compounds in Meteorites  

Microsoft Academic Search

Many organic compounds or their precursorsfound in meteorites originated in the interstellar or circumstellarmedium and were later incorporated intoplanetesimals during the formation of thesolar system. There they either survivedintact or underwent further processing tosynthesize secondary products on themeteorite parent body.The most distinct feature of CI and CM carbonaceouschondrites, two typesof stony meteorites, is their high carbon content(up to 3% of

OLIVER BOTTAand; Jeffrey L. Bada

2002-01-01

11

Industrial Electrosynthesis of Organic Compounds.  

National Technical Information Service (NTIS)

Electrochemical methods are beginning to find uses in the synthesis of different classes of organic compounds with a high degree of purity. The processes of electrochemical synthesis in large-tonnage of some monomers are of special interest because of the...

M. Y. Fioshin A. P. Tomilov

1968-01-01

12

Volatile Organic Compounds in Uremia  

PubMed Central

Background Although “uremic fetor” has long been felt to be diagnostic of renal failure, the compounds exhaled in uremia remain largely unknown so far. The present work investigates whether breath analysis by ion mobility spectrometry can be used for the identification of volatile organic compounds retained in uremia. Methods Breath analysis was performed in 28 adults with an eGFR ?60 ml/min per 1.73 m2, 26 adults with chronic renal failure corresponding to an eGFR of 10–59 ml/min per 1.73 m2, and 28 adults with end-stage renal disease (ESRD) before and after a hemodialysis session. Breath analysis was performed by ion mobility spectrometryafter gas-chromatographic preseparation. Identification of the compounds of interest was performed by thermal desorption gas chromatography/mass spectrometry. Results Breath analyses revealed significant differences in the spectra of patients with and without renal failure. Thirteen compounds were chosen for further evaluation. Some compounds including hydroxyacetone, 3-hydroxy-2-butanone and ammonia accumulated with decreasing renal function and were eliminated by dialysis. The concentrations of these compounds allowed a significant differentiation between healthy, chronic renal failure with an eGFR of 10–59 ml/min, and ESRD (p<0.05 each). Other compounds including 4-heptanal, 4-heptanone, and 2-heptanone preferentially or exclusively occurred in patients undergoing hemodialysis. Conclusion Impairment of renal function induces a characteristic fingerprint of volatile compounds in the breath. The technique of ion mobility spectrometry can be used for the identification of lipophilic uremic retention molecules.

Seifert, Luzia; Slodzinski, Rafael; Jankowski, Joachim; Zidek, Walter; Westhoff, Timm H.

2012-01-01

13

[Detection of organic compounds on Mars].  

PubMed

McKay et al. detected polycyclic aromatic hydrocarbons (PAHs) in Martian meteorite ALH 84001 by two-step laser mass spectrometry. From the presence of PAHs, together with other results, they concluded that there were past life of Mars. On the other hands, no organisms nor organic compounds were detected in Martian regolith in Viking experiments in 1976. In order to obtain solid evidence for organisms or bioorganic compounds compounds on Mars, further analyses of Martian samples are required. There may be four classes of organic compounds on Mars, which are (i) organic compounds abiotically formed from primitive Mars atmosphere, (ii) Organic compounds delivered out of Mars, (iii) Organic compounds biotically formed by Mars organisms, and (iv) Organic compounds abiotically formed from the present Mars atmosphere. Possible organic compounds on Mars and analytical methods for them are discussed. PMID:11540350

Kobayashi, K

1997-03-01

14

Low volatile organic compound paints  

SciTech Connect

Increasingly stringent air emission standards in various states has dictated the elimination of engineering finishes which are derived from high volatile organic compound (VOC) paint chemistries. In July 1989, Allied-Signal, Inc., Kansas City Division, Kansas City, Missouri, voluntarily closed its paint facility, due to non-compliance with local air emission standards. The following details the materials selection and evaluations which led to current processing using low VOC paints, which permitted the Allied Signal, Inc., paint facility to achieve compliance and resume operations. 1 tab.

Martinez, F.E.

1991-01-01

15

Electroreduction of Halogenated Organic Compounds  

NASA Astrophysics Data System (ADS)

The electroreductive cleavage of the carbon-halogen bond in halogenated organic compounds has been extensively studied for more than 70 years, since it is prodromal to a large variety of synthetic applications in organic electrochemistry. Over the years the research interest have progressively included the environmental applications, since several organic halocompounds are known to have (or have had) a serious environmental impact because of their (present or past) wide use as cleaning agents, herbicides, cryogenic fluids, reagents (e.g. allyl and vinyl monomers) for large production materials, etc. Recent studies have also demonstrated the wide spread out- and in-door-presence of volatile organic halides, although at low level, in connexion with residential and non-residential (e.g. stores, restaurants and transportation) activities. In this context, the detoxification of emissions to air, water and land by the selective removal of the halogen group represents a valid treatment route, which, although not leading to the complete mineralization of the pollutants, produces less harmful streams to be easily treated by electrochemical or conventional techniques. The electroreduction process is analysed and discussed in terms of electrode material, reaction medium, cell design and operation, and of substrate classification.

Rondinini, Sandra; Vertova, Alberto

16

Determination of organic compounds in bottled waters  

Microsoft Academic Search

The presence of organic compounds in bottled waters available in the Greek market and their fate when the representative samples exposed at different conditions were the main purposes of this study. The determination of the organic compounds was performed by gas chromatography–mass spectrometry techniques. Disinfection by-products compounds, such as trihalomethanes (THMs) and haloacetic acids (HAAs), were detected at low concentrations

Stavroula V. Leivadara; Anastasia D. Nikolaou; Themistokles D. Lekkas

2008-01-01

17

Organic compounds in municipal landfill leachates  

Microsoft Academic Search

Leachates from three municipal landfills in the Göteborg area of western Sweden were characterised in terms of their content of individual organic compounds. Two of the investigated landfills were still in use during the time of this study. The third landfill was closed down in the mid-seventies. More than 200 individual organic compounds and classes of compounds were identified in

N. Paxéus

2000-01-01

18

Toxicities of “excessively” chlorinated organic compounds  

Microsoft Academic Search

It is now recognized that chlorine can combine with a large variety of organics present in waste waters to form stable organochlorinated compounds (JOLLEY 1973). Moreover, the possible entry of these stable organochlorines into supplies of drinking water has prompted the monitoring of these compounds in many localities (EPA 1974, HARRIS 1974). JOLLEY (1973) identified seventeen stable organochlorine compounds in

Bernice M. Katz; Glenn M. Cohen

1976-01-01

19

Biodegradation of halogenated organic compounds.  

PubMed

In this review we discuss the degradation of chlorinated hydrocarbons by microorganisms, emphasizing the physiological, biochemical, and genetic basis of the biodegradation of aliphatic, aromatic, and polycyclic compounds. Many environmentally important xenobiotics are halogenated, especially chlorinated. These compounds are manufactured and used as pesticides, plasticizers, paint and printing-ink components, adhesives, flame retardants, hydraulic and heat transfer fluids, refrigerants, solvents, additives for cutting oils, and textile auxiliaries. The hazardous chemicals enter the environment through production, commercial application, and waste. As a result of bioaccumulation in the food chain and groundwater contamination, they pose public health problems because many of them are toxic, mutagenic, or carcinogenic. Although synthetic chemicals are usually recalcitrant to biodegradation, microorganisms have evolved an extensive range of enzymes, pathways, and control mechanisms that are responsible for catabolism of a wide variety of such compounds. Thus, such biological degradation can be exploited to alleviate environmental pollution problems. The pathways by which a given compound is degraded are determined by the physical, chemical, and microbiological aspects of a particular environment. By understanding the genetic basis of catabolism of xenobiotics, it is possible to improve the efficacy of naturally occurring microorganisms or construct new microorganisms capable of degrading pollutants in soil and aquatic environments more efficiently. Recently a number of genes whose enzyme products have a broader substrate specificity for the degradation of aromatic compounds have been cloned and attempts have been made to construct gene cassettes or synthetic operons comprising these degradative genes. Such gene cassettes or operons can be transferred into suitable microbial hosts for extending and custom designing the pathways for rapid degradation of recalcitrant compounds. Recent developments in designing recombinant microorganisms and hybrid metabolic pathways are discussed. PMID:2030673

Chaudhry, G R; Chapalamadugu, S

1991-03-01

20

Analysis of Volatile Organic Compounds.  

National Technical Information Service (NTIS)

An improved system is described for reproducibly analyzing, both qualitatively and quantitatively, trace amounts of a large number of organic volatiles existing in a gas sample. Applications include: (1) analyzing the headspace gas of body fluids and comp...

A. Zlatkis

1974-01-01

21

Thermodynamic properties of organic iodine compounds  

NASA Astrophysics Data System (ADS)

A critical evaluation has been made of the thermodynamic properties reported in the literature for 43 organic iodine compounds in the solid, liquid, or ideal gas state. These compounds include aliphatic, cyclic and aromatic iodides, iodophenols, iodocarboxylic acids, and acetyl and benzoyl iodides. The evaluation has been made on the basis of carbon number systematics and group additivity relations, which also allowed to provide estimates of the thermodynamic properties of those compounds for which no experimental data were available. Standard molal thermodynamic properties at 25 °C and 1 bar and heat capacity coefficients are reported for 13 crystalline, 29 liquid, and 39 ideal gas organic iodine compounds, which can be used to calculate the corresponding properties as a function of temperature and pressure. Values derived for the standard molal Gibbs energy of formation at 25 °C and 1 bar of these crystalline, liquid, and ideal gas organic iodine compounds have subsequently been combined with either solubility measurements or gas/water partition coefficients to obtain values for the standard partial molal Gibbs energies of formation at 25 °C and 1 bar of 32 aqueous organic iodine compounds. The thermodynamic properties of organic iodine compounds calculated in the present study can be used together with those for aqueous inorganic iodine species to predict the organic/inorganic speciation of iodine in marine sediments and petroleum systems, or in the near- and far-field of nuclear waste repositories.

Richard, Laurent; Gaona, Xavier

2011-11-01

22

VOLATILE ORGANIC COMPOUNDS AS EXPOSURE BIOMARKERS  

EPA Science Inventory

Alveolar breath sampling and analysis can be extremely useful in exposure assessment studies involving volatile organic compounds (VOCs). Over recent years scientists from the US Environmental Protection Agency's National Exposure Research Laboratory have developed and refined...

23

BIORESTORATION OF AQUIFERS CONTAMINATED WITH ORGANIC COMPOUNDS  

EPA Science Inventory

Techniques available to remediate ground water contaminated with organic compounds. These include physical containment, in situ treatment with chemicals or microbes, and withdrawal and treatment via various forms of physical, chemical, or biological processes. (Copyright (c) CRC ...

24

(CHINA) PERFLUORINATED ORGANIC COMPOUND EXPOSURE ASSESSMENT RESEARCH  

EPA Science Inventory

A wide range of perfluorinated organic compounds (PFCs) has been used in a variety of industrial processes and consumer products. The most commonly studied PFCs include perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), but there are many more compounds in this c...

25

FREQUENCY OF ORGANIC COMPOUNDS IDENTIFIED IN WATER  

EPA Science Inventory

This study was initiated for the purpose of compiling a list of all organic compounds that have been found in water. This report contains the names of compounds found, their location or a reference to a published study, the type of water in which they are found, and the date of s...

26

Organic compounds passage through RO membranes  

Microsoft Academic Search

Organic solute permeation, sorption, and rejection by reverse osmosis membranes, from aqueous solutions, were studied experimentally and via artificial neural networks (ANN)-based quantitative structure–property relations (QSPR), for a set of fifty organic compounds for polyamide and cellulose acetate membranes. Membrane solute sorption and passage for dead-end filtration model experiments were quantified based on radioactivity measurements for radiolabeled compounds in the

Dan Libotean; Jaume Giralt; Robert Rallo; Yoram Cohen; Francesc Giralt; Harry F. Ridgway; Grisel Rodriguez; Don Phipps

2008-01-01

27

Organic Compounds used in Aquaculture  

Microsoft Academic Search

The transport patterns and potential direct or indirect effects on the environment or even on human health of agents used\\u000a in aquaculture like antibiotics, triphenylmethane dyes and hormones used to modify sex ratios have barely been defined. Even\\u000a at trace levels, hormones may influence the endocrine systems of non-target organisms due to their high biological low-dose\\u000a activity. Antibiotics are often

Thomas Heberer

28

Organic mercury compounds and autoimmunity  

Microsoft Academic Search

Based on in vitro studies and short-term in vivo studies, all mercurials were for a long time considered as prototypic immunosuppressive substances. Recent studies have confirmed that organic mercurials such as methyl mercury (MeHg) and ethyl mercury (EtHg) are much more potent immunosuppressors than inorganic mercury (Hg). However, Hg interacts with the immune system in the presence of a susceptible

Said Havarinasab; Per Hultman

2005-01-01

29

Alkylation of organic aromatic compounds  

DOEpatents

Aromatic compounds are alkylated in a combination reactor/distillation column comprising a vessel suitable for operating between 70 C and 500 C and from 0.5 to 20 atmospheres pressure; an inert distillation packing in the lower one-third of said vessel; solid acidic catalytic material such as zeolites or an acidic cation exchange resin supported in the middle one-third of said vessel; and inert distillation packing in the upper one-third of said vessel. A benzene inlet is located near the upper end of the vessel; an olefin inlet is juxtaposed with said solid acidic catalytic material; a bottoms outlet is positioned near the bottom of said vessel for removing said cumene and ethyl benzene; and an overhead outlet is placed at the top of said vessel for removing any unreacted benzene and olefin.

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

1993-01-05

30

Semivolatile organic compounds in indoor environments  

Microsoft Academic Search

Semivolatile organic compounds (SVOCs) are ubiquitous in indoor environments, redistributing from their original sources to all indoor surfaces. Exposures resulting from their indoor presence contribute to detectable body burdens of diverse SVOCs, including pesticides, plasticizers, and flame retardants. This paper critically examines equilibrium partitioning of SVOCs among indoor compartments. It proceeds to evaluate kinetic constraints on sorptive partitioning to organic

Charles J. Weschler; William W. Nazaroff

2008-01-01

31

Sulfate minerals and organic compounds on Mars  

NASA Astrophysics Data System (ADS)

Strong evidence for evaporitic sulfate minerals such as gypsum and jarosite has recently been found on Mars. Although organic molecules are often codeposited with terrestrial evaporitic minerals, there have been no systematic investigations of organic components in sulfate minerals. We report here the detection of organic material, including amino acids and their amine degradation products, in ancient terrestrial sulfate minerals. Amino acids and amines appear to be preserved for geologically long periods in sulfate mineral matrices. This suggests that sulfate minerals should be prime targets in the search for organic compounds, including those of biological origin, on Mars.

Aubrey, Andrew; Cleaves, H. James; Chalmers, John H.; Skelley, Alison M.; Mathies, Richard A.; Grunthaner, Frank J.; Ehrenfreund, Pascale; Bada, Jeffrey L.

2006-05-01

32

Metastable Equilibria Among Aqueous Organic Compounds  

NASA Astrophysics Data System (ADS)

Metastable equilibrium states exist when reactions among a subset of compounds in a chemical system are reversible even though other irreversible reactions exist in the same system. The existence of metastable equilibrium among organic compounds was initially detected by comparing ratios of organic acid concentrations reported for oil-field brines (Shock, 1988, Geology 16, 886-890; Shock, 1989, Geology 17, 572-573), and calculating the same ratios for likely oxidation states determined by mineral assemblages and mixtures of hydrocarbons in coexisting petroleum (Shock, 1994, in: The Role of Organic Acids in Geological Processes, Springer). This led to the notion of extending the concept of metastable equilibrium states to explicitly account for petroleum compositions (Helgeson et al., 1993, GCA, 57, 3295-3339), which eventually yielded the concept of hydrolytic disproportionation of kerogens to produce petroleum and CO2(g) (Helgeson et al., 2009, GCA, 73, 594-695). Experimental tests of metastable equilibrium among organic compounds began with the identification of reversible reactions between alkanes and alkenes that are dependent on the H2 fugacity of the experimental system (Seewald, 1994, Nature 370, 285-287). These were followed with a comprehensive series of long-term experiments leading to the hypothesis that reversible reactions include alkanes, alkenes, alcohol, aldehydes, ketones and carboxylic acids (e.g., Seewald, 2001, GCA 65, 1641-1664; 2003, Nature 426, 327-333; McCollom & Seewald, 2003, GCA 67, 3645-3664). We have conducted sets of hydrothermal organic transformation experiments that test the extent to which these reactions are indeed reversible using aromatic and cyclic compounds. Results demonstrate reversibility for reactions among dibenzyl ketone, 1,3-diphenyl-2-propanol, 1,3-diphenylpropene and 1,3-diphenylpropane, as well as among methylcyclohexanes, methylcyclohexenes, methylcyclohexanols, methylcyclohexanones and methylcyclohexadienes. The compounds chosen for study include structural features that provide mechanistic insight into the reactions. By including cyclic and aromatic compounds, these results expand the diversity of organic compounds that react reversibly in geochemical processes. It follows that metastable equilibria among organic compounds may be inescapable during hydrothermal alteration and petroleum generation.

Shock, E.; Shipp, J.; Yang, Z.; Gould, I. R.

2011-12-01

33

Volatile Organic Compounds Fibre Optic Nanosensor  

Microsoft Academic Search

A novel vapochromic material of formula (Au2Ag2(C6F5)4(C6H5N)2) has been used to develop a volatile organic compounds (VOCs) sensor. This product changes its optical properties, such as colour or refractive index, when exposed to some organic vapours. The sensor consists of a nanometer-scale Fizeau interferometer doped with the above mentioned vapochromic complex and built onto a cleaved end of a multimode

César Elosúaa; Cándido Bariáina; Ignacio R. Matías; Francisco J. Arreguia; Asunción Luquin; Mariano Laguna; Julián Garrido

34

Trace organic compounds in the marine environment  

Microsoft Academic Search

Trace organic chemicals include a range of compounds which, due to a combination of their physico-chemical properties and toxicological implications, have been described as a serious threat to the biotic environment. A global treaty to regulate the manufacture and release of some of the most persistent trace chemicals has been promulgated and signed.The marine environment is an important sink for

Michael R Moore; Walter Vetter; Caroline Gaus; Glen R Shaw; Jochen F Müller

2002-01-01

35

RAPID MICRODETERMINATION OF FLUORINE IN ORGANIC COMPOUNDS  

Microsoft Academic Search

In a rapid and accurate method for the microdetermination of fluorine in ; organic compounds the Schoniger combustion technique is used for initial ; decomposition of the sample, followed by an improved ferric salicylate ; colorimetric analysis. Samples ranging from 0.4 to 20 mg. were successfully ; analyzed in 10 to 20 minutes. Accuracy and precision are adequate for ;

R. N. Rogers; S. K. Yasuda

1959-01-01

36

Emerging Control Technologies for Volatile Organic Compounds  

Microsoft Academic Search

Environmental problems associated with volatile organic compounds (VOCs) in the atmosphere have provided the driving force for sustained fundamental and applied research in the area of environmental remediation. Conventional methods currently used to treat VOCs include incineration, condensation, adsorption, and absorption. Incineration and condensation are cost-effective only for moderate to high VOC concentrations. Adsorption and absorption do not destroy VOCs

Geeta Rani Parmar; N. N. Rao

2008-01-01

37

Global Exposure Modelling of Semivolatile Organic Compounds  

NASA Astrophysics Data System (ADS)

Organic compounds which are persistent and toxic as the agrochemicals ?-hexachlorocyclohexane (?-HCH, lindane) and dichlorodiphenyltrichloroethane (DDT) pose a hazard for the ecosystems. These compounds are semivolatile, hence multicompartmental substances and subject to long-range transport (LRT) in atmosphere and ocean. Being lipophilic, they accumulate in exposed organism tissues and biomagnify along food chains. The multicompartmental global fate and LRT of DDT and lindane in the atmosphere and ocean have been studied using application data for 1980, on a decadal scale using a model based on the coupling of atmosphere and (for the first time for these compounds) ocean General Circulation Models (ECHAM5 and MPI-OM). The model system encompasses furthermore 2D terrestrial compartments (soil and vegetation) and sea ice, a fully dynamic atmospheric aerosol (HAM) module and an ocean biogeochemistry module (HAMOCC5). Large mass fractions of the compounds are found in soil. Lindane is also found in comparable amount in ocean. DDT has the longest residence time in almost all compartments. The sea ice compartment locally almost inhibits volatilization from the sea. The air/sea exchange is also affected , up to a reduction of 35 % for DDT by partitioning to the organic phases (suspended and dissolved particulate matter) in the global oceans. Partitioning enhances vertical transport in the sea. Ocean dynamics are found to be more significant for vertical transport than sinking associated with particulate matter. LRT in the global environment is determined by the fast atmospheric circulation. Net meridional transport taking place in the ocean is locally effective mostly via western boundary currents, upon applications at mid- latitudes. The pathways of the long-lived semivolatile organic compounds studied include a sequence of several cycles of volatilisation, transport in the atmosphere, deposition and transport in the ocean (multihopping substances). Multihopping is more significant for DDT than for lindane. It enhances the LRT potential for both compounds.

Guglielmo, F.; Lammel, G.; Maier-Reimer, E.

2008-12-01

38

Nonvolatile organic compounds in treated waters.  

PubMed Central

Over the past decade much information has been published on the analysis of organics extracted from treated water. Certain of these organics have been shown to be by-products of the chlorination disinfection process and to possess harmful effects at high concentrations. This has resulted in increased interest in alternative disinfection processes, particularly ozonation. The data on organics had been largely obtained by using gas chromatography-mass spectrometry, which is only capable of analyzing, at best, 20% of the organics present in treated water. Research in key areas such as mutagenicity testing of water and characterization of chlorination and ozonation by-products has emphasized the need for techniques suitable for analysis of the remaining nonvolatile organics. Several methods for the isolation of nonvolatile organics have been evaluated and, of these, freeze-drying followed by methanol extraction appears the most suitable. Reverse-phase HPLC was used for separation of the methanol extract, but increased resolution for separation of the complex mixtures present is desirable. In this context, high resolution size exclusion chromatography shows promise. Characterization of separated nonvolatiles is possible by the application of state-of-the-art mass spectrometric techniques. Results obtained by these techniques have shown that the nonvolatile organic fraction of chlorinated drinking water consists of many discrete compounds. Among these, some of the chlorinated compounds are almost certainly by-products of disinfection. Studies of the by-products of ozonation of fulvic and humic acids isolated from river waters have indicated a similar proportion of nonvolatile organics. Further, ozonation can result in the release of compounds that are trapped in the macromolecules.

Watts, C D; Crathorne, B; Fielding, M; Killops, S D

1982-01-01

39

Organic Compounds in Savannah River Site High-Level Waste  

SciTech Connect

The present study identifies organic compounds or classes of compounds that may occur in SRS high-level waste (HLW) based on a review of previous sample analyses and records of disposals of organic compounds to the HLW tank farms.

Walker, D.D.

2002-12-17

40

Organic photosensitive devices using subphthalocyanine compounds  

DOEpatents

An organic photosensitive optoelectronic device, having a donor-acceptor heterojunction of a donor-like material and an acceptor-like material and methods of making such devices is provided. At least one of the donor-like material and the acceptor-like material includes a subphthalocyanine, a subporphyrin, and/or a subporphyrazine compound; and/or the device optionally has at least one of a blocking layer or a charge transport layer, where the blocking layer and/or the charge transport layer includes a subphthalocyanine, a subporphyrin, and/or a subporphyrazine compound.

Rand, Barry (Princeton, NJ); Forrest, Stephen R. (Ann Arbor, MI); Mutolo, Kristin L. (Hollywood, CA); Mayo, Elizabeth (Alhambra, CA); Thompson, Mark E. (Anaheim Hills, CA)

2011-07-05

41

Organic Aerosols: A Potential Source of Oxygenated Volatile Organic Compounds  

NASA Astrophysics Data System (ADS)

Numerous laboratory studies have demonstrated that organic surfaces are readily oxidized by O3 and OH, in many cases producing oxygenated volatile organic compounds (OVOC) such as aldehydes and organic acids. Because many aerosols possess organic coatings, it is possible that oxidation of organic aerosol surfaces could provide a significant flux of OVOC into the troposphere that is not accounted for in current models. From data collected on the NASA DC-8 during INTEX-NA over North America in the summer of 2004 (part of ICARTT -- the International Consortium for Atmospheric Research on Transport and Transformation), we estimate the potential flux of OVOC from organic aerosol oxidation, and discuss its implications for our understanding of atmospheric photochemistry.

Kwan, A. J.; Crounse, J. D.; Wennberg, P. O.

2005-12-01

42

Synthesis and Characterization of Organic NLO Compound  

NASA Astrophysics Data System (ADS)

Organic compound 1-(2 thiophene)-3-(2, 3, 5-trichloroph enyl)-2-propen-1-one [TTCP] with molecular formula C13H7Cl3OS was synthesized using condensation reaction method. FT-IR spectra were recorded to identify the various functional groups present in the compound. The third harmonic optical nonlinearity test was carried out using z-scan technique. The single crystals were grown using slow evaporation solution growth technique. Optical absorption studies reveal that the crystal is transparent in the entire visible region and absorption (around 364 nm) takes place in the UV-region. The single-crystal XRD studies were carried out, and it was found that the compound crystallizes in the monoclinic system with a space group P21/c. The observed lattice parameters are a = 16.6170(6) A? b = 7.6180(5) A? c = 10.9280(11) A? and V = 1338.47(17) A?3.

Kumar, P. C. Rajesh; Ravindrachary, V.; Janardhana, K.; Manjunath, H. R.; Karegoudar, Prakash

2011-07-01

43

Microbiological degradation of atmospheric organic compounds  

NASA Astrophysics Data System (ADS)

Until now, aerosol transformation was assumed to be via chemical or physical processes. Here we present evidence that an important class of organic aerosols - dicarboxylic acids (DCA) - can be efficiently transformed by existing airborne microbes (bacteria and fungi) in the boundary layer. Isotopic studies indicate that microbiological entities transform and use DCA as nutrients. Several observed products are toxicants or pathogens. Identified volatile products indicate that DCA can be recycled back to the atmosphere via microbiological processes. Thus, biodegradation could be an important atmospheric transformation pathway for organic compounds.

Ariya, Parisa A.; Nepotchatykh, Oleg; Ignatova, Olga; Amyot, Marc

2002-11-01

44

Volatile organic compounds (VOCs) in soils  

Microsoft Academic Search

Soils may act as sources or sinks of volatile organic compounds (VOCs). Many of the formed VOCs are produced by microorganisms,\\u000a and it would be a challenge to investigate soil microbial communities by studying their VOC profile. Such “volatilomics” would\\u000a have the advantage of avoiding extraction steps that are often a limit in genomic or proteomic approaches. Abundant literature\\u000a on

Heribert Insam; Martin S. A. Seewald

2010-01-01

45

Methods for determination of toxic organic compounds in air  

SciTech Connect

This paper provides environmental regulatory agencies, industry, and other interested parties with specific, standardized sampling and analysis procedures for toxic organic compounds in air. Compounds include Volatile Organic Compounds, Organochlorine Pesticides and PCBs, Aldehydes and Ketones, Phosgene, N-Nitrosodimethylamine, Phenol and Methylphenols (Cresols), Polychlorinated Dibenzo-p-Dioxins (PCDDs), Formaldehyde, Non-Methane Organic Compounds (NMOCs) and Polynuclear Aromatic Hydrocarbons (PAHs).

Winberry, W.T. Jr.

1990-01-01

46

Preparing Soil Samples for Volatile Organic Compound Analysis.  

National Technical Information Service (NTIS)

Three equilibrium headspace and three solvent extraction methods of preparing soil samples for determining volatile organic compounds (VOCs) were compared. Soil samples were spiked with five gasoline range aromatic compounds and four chlorinated compounds...

A. D. Hewitt

1997-01-01

47

Volatile Organic Compound Analysis in Istanbul  

NASA Astrophysics Data System (ADS)

Volatile Organic Compound Analysis in Istanbul Ö. Çapraz1, A. Deniz1,3, A. Ozturk2, S. Incecik1, H. Toros1 and, M. Coskun1 (1) Istanbul Technical University, Faculty of Aeronautics and Astronautics, Department of Meteorology, 34469, Maslak, Istanbul, Turkey. (2) Istanbul Technical University, Faculty of Chemical and Metallurgical, Chemical Engineering, 34469, Maslak, Istanbul, Turkey. (3) Marmara Clean Air Center, Ministry of Environment and Urbanization, Ni?anta??, 34365, ?stanbul, Turkey. One of the major problems of megacities is air pollution. Therefore, investigations of air quality are increasing and supported by many institutions in recent years. Air pollution in Istanbul contains many components that originate from a wide range of industrial, heating, motor vehicle, and natural emissions sources. VOC, originating mainly from automobile exhaust, secondhand smoke and building materials, are one of these compounds containing some thousands of chemicals. In spite of the risks to human health, relatively little is known about the levels of VOC in Istanbul. In this study, ambient air quality measurements of 32 VOCs including hydrocarbons, halogenated hydrocarbons and carbonyls were conducted in Ka??thane (Golden Horn) region in Istanbul during the winter season of 2011 in order to develop the necessary scientific framework for the subsequent developments. Ka??thane creek valley is the source part of the Golden Horn and one of the most polluted locations in Istanbul due to its topographical form and pollutant sources in the region. In this valley, horizontal and vertical atmospheric motions are very weak. The target compounds most commonly found were benzene, toluene, xylene and ethyl benzene. Concentrations of total hydrocarbons ranged between 1.0 and 10.0 parts per billion, by volume (ppbv). Ambient air levels of halogenated hydrocarbons appeared to exhibit unique spatial variations and no single factor seemed to explain trends for this group of compounds. N-octane, 3-methylheptane, n-nonane, 2,3,4-trimethylpentane and n-hexane parameters ranged between 3 ppbv and maximum value of 10 ppbv. The other VOC parameters are measured below 3 ppbv value. At participating urban locations for the year of data considered, levels of carbonyls were higher than the level of the other organic compound groups, suggesting that emissions from motor vehicles and photochemical reactions strongly in?uence ambient air concentrations of carbonyls. Of the most prevalent carbonyls, formaldehyde and acetaldehyde were the dominant compounds, ranging from 1.5-7.4 ppbv for formaldehyde, to 0.8-2.7 ppbv for acetaldehyde. Keywords: Air quality, Volatile Organic Compounds (VOC), industry, meteorology, urban, Ka??thane, ?stanbul. Acknowledgment: This work was part of the TUJJB-TUMEHAP-01-10 and Turkish Scientific and Technical Research Council Project No: 109Y132.

?apraz, Ö.; Deniz, A.; Öztürk, A.; Incecik, S.; Toros, H.; Co?kun, M.

2012-04-01

48

Semivolatile organic compounds in indoor environments  

NASA Astrophysics Data System (ADS)

Semivolatile organic compounds (SVOCs) are ubiquitous in indoor environments, redistributing from their original sources to all indoor surfaces. Exposures resulting from their indoor presence contribute to detectable body burdens of diverse SVOCs, including pesticides, plasticizers, and flame retardants. This paper critically examines equilibrium partitioning of SVOCs among indoor compartments. It proceeds to evaluate kinetic constraints on sorptive partitioning to organic matter on fixed surfaces and airborne particles. Analyses indicate that equilibrium partitioning is achieved faster for particles than for typical indoor surfaces; indeed, for a strongly sorbing SVOC and a thick sorptive reservoir, equilibrium partitioning is never achieved. Mass-balance considerations are used to develop physical-science-based models that connect source- and sink-rates to airborne concentrations for commonly encountered situations, such as the application of a pesticide or the emission of a plasticizer or flame retardant from its host material. Calculations suggest that many SVOCs have long indoor persistence, even after the primary source is removed. If the only removal mechanism is ventilation, moderately sorbing compounds ( Koa > 10 10) may persist indoors for hundreds to thousands of hours, while strongly sorbing compounds ( Koa > 10 12) may persist for years. The paper concludes by applying the newly developed framework to explore exposure pathways of building occupants to indoor SVOCs. Accumulation of SVOCs as a consequence of direct air-to-human transport is shown to be potentially large, with a maximum indoor-air processing rate of 10-20 m 3/h for SVOC uptake by human skin, hair and clothing. Levels on human skin calculated with a simple model of direct air-to-skin transfer agree remarkably well with levels measured in dermal hand wipes for SVOCs possessing a wide range of octanol-air partition coefficients.

Weschler, Charles J.; Nazaroff, William W.

49

Alternatives to Automotive Consumer Products That Use Volatile Organic Compounds (VOC) and/or Chlorinated Organic Compound Solvents. Addendum.  

National Technical Information Service (NTIS)

This addendum to the document entitled 'Alternatives to Automotive Consumer Products that use Volatile Organic Compounds (VOC) and/or Chlorinated Organic Compound Solvents' presents the questionnaires that were filled out by the staff of the Institute for...

D. Wolf J. Zavadil M. Morris

2004-01-01

50

IRRADIATION METHOD OF CONVERTING ORGANIC COMPOUNDS  

DOEpatents

A method is given for changing the distribution of organic compounds from that produced by the irradiation of bulk alkane hydrocarbons. This method consists of depositing an alkane hydrocarbon on the surface of a substrate material and irradiating with gamma radiation at a dose rate of more than 100,000 rads. The substrate material may be a metal, metal salts, metal oxides, or carbons having a surface area in excess of 1 m/sup 2//g. The hydrocarbons are deposited in layers of from 0.1 to 10 monolayers on the surfaces of these substrates and irradiated. The product yields are found to vary from those which result from the irradiation of bulk hydrocarbons in that there is an increase in the quantity of branched hydrocarbons.

Allen, A.O.; Caffrey, J.M. Jr.

1960-10-11

51

Shock Modifications of Organic Compounds in Carbonaceous Chondrite Parent Bodies  

Microsoft Academic Search

Impacts among asteroidal objects would have altered or destroyed pre-existing organic matter in both targets and projectiles to a greater or lesser degree depending upon impact velocities. To begin filling a knowledge gap on the shock metamorphism of organic compounds, we are studying the effects of shock impacts on selected classes of organic compounds utilizing laboratory shock facilities. Our approach

George W. Cooper

1998-01-01

52

ACUTE TOXICITY OF SELECTED ORGANIC COMPOUNDS TO FATHEAD MINNOWS  

EPA Science Inventory

Static nonrenewal laboratory bioassays were conducted with 26 organic compounds commonly used by industry. The selected compounds represented the five following chemical classes: acids, alcohols, hydrocarbons, ketones and aldehydes, and phenols. Juvenile fathead minnows (Pimephal...

53

GLOBAL INVENTORY OF VOLATILE ORGANIC COMPOUND EMISSIONS FORM ANTHROPOGENIC SOURCES  

EPA Science Inventory

The report describes a global inventory anthropogenic volatile organic compound (VOC) emissions that includes a separate inventory for each of seven pollutant groups--paraffins, olefins, aromatics, formaldehyde, other aldehydes, other aromatics, and marginally reactive compounds....

54

Voltammetric analysis of N-containing drugs using the hanging galinstan drop electrode (HGDE).  

PubMed

The electrochemical behaviour of several N-containing voltammetric active drugs such as 1,4-benzodiazepines (chlordiazepoxide, nitrazepam and diazepam) as well as one nitro-compound (nitrofurantoin) and one azo-compound (phenazopyridine) is described using a new kind of liquid electrode, the hanging galinstan drop electrode. Concentrations of 10(-5) - 10(-8) mol L(-1) are generally measurable. Differential pulse and adsorptive stripping voltammograms are recorded in different supporting electrolytes, like 0.1 M KNO3, acetate buffer solution pH = 4.6 and phosphate buffer solution pH = 7.0. The effects of varying the starting potentials, U(start) for DPV and accumulation times, t(acc) for AdSV are considered. Briefly, it is shown that the novel galinstan electrode is suitable for reducing several functional groups in organic substances, here presented for N-oxide-, azomethine-, nitro- and azo-groups. PMID:19348337

Channaa, H; Surmann, P

2009-03-01

55

Volatile organic compound remedial action project  

SciTech Connect

This Environmental Assessment (EA) reviews a proposed project that is planned to reduce the levels of volatile organic compound (VOC) contaminants present in the Mound domestic water supply. The potable and industrial process water supply for Mound is presently obtained from a shallow aquifer via on-site production wells. The present levels of VOCs in the water supply drawn from the on-site wells are below the maximum contaminant levels (MCLs) permissible for drinking water under Safe Drinking Water Act (SDWA; 40 CFR 141); however, Mound has determined that remedial measures should be taken to further reduce the VOC levels. The proposed project action is the reduction of the VOC levels in the water supply using packed tower aeration (PTA). This document is intended to satisfy the requirements of the National Environmental Policy Act (NEPA) of 1969 and associated Council on Environmental Quality regulations (40 CFR parts 1500 through 1508) as implemented through U.S. Department of Energy (DOE) Order 5440.1D and supporting DOE NEPA Guidelines (52 FR 47662), as amended (54 FR 12474; 55 FR 37174), and as modified by the Secretary of Energy Notice (SEN) 15-90 and associated guidance. As required, this EA provides sufficient information on the probable environmental impacts of the proposed action and alternatives to support a DOE decision either to prepare an Environmental Impact Statement (EIS) or issue a Finding of No Significant Impact (FONSI).

NONE

1991-12-01

56

FIELD SCREENING FOR HALOGENATED VOLATILE ORGANIC COMPOUNDS  

SciTech Connect

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.

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

2002-06-01

57

Volatile Organic Compounds Contribute to Airway Hyperresponsiveness  

PubMed Central

Background Volatile organic compounds (VOCs) in concentrations found in both the work and home environments may influence lung function. We investigated the prevalence of airway responsiveness in workers exposed to VOCs. Methods We used allergic skin tests, nonspecific airway hyperresponsiveness testing and questionnaires to study twenty exposed workers and twenty-seven control subjects. Atopy was defined as a reactor who showed >3+ response to one or more allergens on the skin prick tests. Airway hyperresponsiveness (BRindex) was defined as log [% fall of FEV1/ log (last concentration of methacholine) +10]. Results The VOC exposed workers, in comparison with the control subjects, tended to have a higher BRindex (1.19±0.07 vs. 1.15±0.08, respectively). Workers exposed to VOCs with atopy or smoker, as compared with the workers exposed to VOCs with non-atopy and who were non-smokers and the control subjects with non-atopy and who were non-smokers, had a significantly higher BRindex (1.20±0.05 vs. 1.14±0.06 vs. 1.10±0.03, respectively p<0.05). The BRindex was not correlated with atopy, the smoking status or the duration of VOC exposure. Conclusions These findings suggest that VOCs may act as a contributing factor of airway hyperresponsiveness in workers exposed to VOCs.

Jang, An-Soo; Choi, Inseon-S; Koh, Young-Il

2007-01-01

58

Volatile Organic Compound Emissions by Agricultural Crops  

NASA Astrophysics Data System (ADS)

Biogenic Volatile Organic Compounds (BVOCs) participate in ozone and aerosol formation, and comprise a substantial fraction of reactive VOC emission inventories. In the agriculturally intensive Central Valley of California, emissions from crops may substantially influence regional air quality, but emission potentials have not been extensively studied with advanced instrumentation for many important crops. Because crop emissions may vary according to the species, and California emission inventories are constructed via a bottom-up approach, a better knowledge of the emission rate at the species-specific level is critical for reducing uncertainties in emission inventories and evaluating emission model performance. In the present study we identified and quantified the BVOCs released by dominant agricultural crops in California. A screening study to investigate both volatile and semivolatile BVOC fractions (oxygenated VOCs, isoprene, monoterepenes, sesquiterpenes, etc.) was performed for 25 crop species (at least 3 replicates plants each), including branch enclosures of woody species (e.g. peach, mandarin, grape, pistachio) and whole plant enclosures for herbaceous species (e.g. onion, alfalfa, carrot), through a dynamic cuvette system with detection by PTRMS, in-situ GCMS/FID, and collection on carbon-based adsorbents followed by extraction and GCMS analysis. Emission data obtained in this study will allow inclusion of these crops in BVOC emission inventories and air quality simulations.

Ormeno, E.; Farres, S.; Gentner, D.; Park, J.; McKay, M.; Karlik, J.; Goldstein, A.

2008-12-01

59

Kinetics of desorption of organic compounds from dissolved organic matter.  

PubMed

This study presents a new experimental technique for measuring rates of desorption of organic compounds from dissolved organic matter (DOM) such as humic substances. The method is based on a fast solid-phase extraction of the freely dissolved fraction of a solute when the solution is flushed through a polymer-coated capillary. The extraction interferes with the solute-DOM sorption equilibrium and drives the desorption process. Solutes which remain sorbed to DOM pass through the extraction capillary and can be analyzed afterward. This technique allows a time resolution for the desorption kinetics from subseconds up to minutes. It is applicable to the study of interaction kinetics between a wide variety of hydrophobic solutes and polyelectrolytes. Due to its simplicity it is accessible for many environmental laboratories. The time-resolved in-tube solid-phase microextraction (TR-IT-SPME) was applied to two humic acids and a surfactant as sorbents together with pyrene, phenanthrene and 1,2-dimethylcyclohexane as solutes. The results give evidence for a two-phase desorption kinetics: a fast desorption step with a half-life of less than 1 s and a slow desorption step with a half-life of more than 1 min. For aliphatic solutes, the fast-desorbing fraction largely dominates, whereas for polycyclic aromatic hydrocarbons such as pyrene, the slowly desorbing, stronger-bound fraction is also important. PMID:22035249

Kopinke, Frank-Dieter; Ramus, Ksenia; Poerschmann, Juergen; Georgi, Anett

2011-11-10

60

Secondary organic aerosol from biogenic volatile organic compound mixtures  

NASA Astrophysics Data System (ADS)

The secondary organic aerosol (SOA) yields from the ozonolysis of a Siberian fir needle oil (SFNO), a Canadian fir needle oil (CFNO), and several SOA precursor mixtures containing reactive and non-reactive volatile organic compounds (VOCs) were investigated. The use of precursor mixtures more completely describes the atmosphere where many VOCs exist. The addition of non-reactive VOCs such as bornyl acetate, camphene, and borneol had very little to no effect on SOA yields. The oxidation of VOC mixtures with VOC mass percentages similar to the SFNO produced SOA yields that became more similar to the SOA yield from SFNO as the complexity and concentration of VOCs within the mixture became more similar to overall SFNO composition. The SOA yield produced by the oxidation of CFNO was within the error of the SOA yield produced by the oxidation of SFNO at a similar VOC concentration. The SOA yields from SFNO were modeled using the volatility basis set (VBS), which predicts the SOA yields for a given mass concentration of mixtures containing similar VOCs.

Hatfield, Meagan L.; Huff Hartz, Kara E.

2011-04-01

61

Separation of Organic Compounds from Surfactant Solutions: A Review  

Microsoft Academic Search

This review summarizes the recent development in separation of emulsified organic compounds from surfactant solutions for surfactant reuse and\\/or surfactant?contaminant disposal. Three major principles have been employed for separating organic compounds and\\/or surfactants from aqueous solutions, namely, organic compound inter?phase mass transfer, surfactant micelle removal, and manipulation of surfactant solution phase behavior. Details of these principles and their applications are

Hefa Cheng; David A. Sabatini

2007-01-01

62

[Quantification assessment of the relationship between chemical and olfactory concentrations for malodorous volatile organic compounds].  

PubMed

Using self-made cold-traps and gas bags, the odor samples were collected from 6 sewage treatment workshops of a typical municipal sewage treatment plant in Guangzhou City. The chemical composition and olfactory concentrations of these samples were respectively analyzed by thermal-desorption/GC-MS and triangle odor bag method. Finally, a mathematical equation was built for assessing the relationship between principal organic odorants and the olfactory concentrations. The result showing that: (1) More than 70 volatile organic compounds were detected in municipal sewage treatment plant, among which were 30 malodorous volatile organic compounds (MVOCs), ranging from 0.37 to 1 872.24 microg x m(-3) and appearing in sludge dewatering, thickening and aeration tank with the highest concentrations. (2) Principle component analysis was used to group the target MVOCs into 5 categories: benzenes, halohydrocarbons, aldehydes, hydrocarbons and S, N-containing organic compounds. (3) Multiple lineal regression analysis was used to build a quantified relationship between chemical and olfactory concentrations of MVOCs. The result indicated that 25% of the odor problem of sewage treatment unit was due to MVOCs. The predicted values were fitting well with measured values. The sensitivity of mathematical equation for measuring odor concentration was higher than that of human olfactory system. PMID:22468522

Liu, Shu-Le; Wang, Bo-Guang; He, Jie; Tang, Xiao-Dong; Zhao, De-Jun; Guo, Wei

2011-12-01

63

POTENTIAL EMISSIONS OF HAZARDOUS ORGANIC COMPOUNDS FROM SEWAGE SLUDGE INCINERATION  

EPA Science Inventory

Laboratory thermal decomposition studies were undertaken to evaluate potential organic emissions from sewage sludge incinerators. Precisely controlled thermal decomposition experiments were conducted on sludge spiked with mixtures of hazardous organic compounds, on the mixtures o...

64

40 CFR 60.582 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2010 CFR

...Subpart Fff - Standards of Performance for Flexible Vinyl and Urethane] [Sec. 60.582 - Standard for volatile organic compounds...SOURCES-- Standards of Performance for Flexible Vinyl and Urethane Sec. 60.582 Standard for volatile organic...

2009-07-01

65

Effects of Cr(III) organic compounds on Lactobacillus plantarum  

Microsoft Academic Search

Biotransformation of Cr(VI) to less toxic Cr(III) has been known to produce insoluble Cr(III) compounds and soluble Cr(III) organic complexes. However, recent research reports have indicated that Cr(III) organic complexes are relatively stable in the environment. Little has been reported on the fate and toxic effects of Cr(III) organic compounds on organisms. In this study, the toxic effects of the

Titus Wambua Mutisya; Zejiao Luo; Nivedita Chatterjee

2010-01-01

66

Nitrated Secondary Organic Tracer Compounds in Biomass Burning Smoke  

NASA Astrophysics Data System (ADS)

Natural and human-initiated biomass burning releases large amounts of gases and particles into the atmosphere, impacting climate, environment and affecting public health. Several hundreds of compounds are emitted from biomass burning and these compounds largely originate from the pyrolysis of biopolymers such as lignin, cellulose and hemicellulose. Some of compounds are known to be specific to biomass burning and widely recognized as tracer compounds that can be used to identify the presence of biomass burning PM. Detailed chemical analysis of biomass burning influenced PM samples often reveals the presence compounds that correlated well with levoglucosan, a known biomass burning tracer compound. In particular, nitrated aromatic compounds correlated very well with levoglucosan, indicating that biomass burning as a source for this class of compounds. In the present study, we present evidence for the presence of biomass burning originating secondary organic aerosol (BSOA) compounds in biomass burning influenced ambient PM. These BSOA compounds are typically nitrated aromatic compounds that are produced in the oxidation of precursor compounds in the presence of NOx. The precursor identification was performed from a series of aerosol chamber experiments. m-Cresol, which is emitted from biomass burning at significant levels, is found to be a major precursor compounds for nitrated BSOA compounds found in the ambient PM. We estimate that the total concentrations of these compounds in the ambient PM are comparable to biogenic SOA compounds in winter months, indicating the BSOA contributes important amounts to the regional organic aerosol loading.

Iinuma, Y.; Böge, O.; Gräfe, R.; Herrmann, H.

2010-12-01

67

Identification of Organic Compounds by Gas Chromatography  

Microsoft Academic Search

THE identification of unknown compounds separated by gas chromatography is often effected by comparison of their retention values with those of known compounds together with infra-red spectro-photometry or mass spectrometry. For this purpose graphs are prepared of log r against boiling point or log r on one stationary phase against log r on another stationary phase, where r is the

Ian Brown

1960-01-01

68

Volatile chelates and organic compounds of neptunium and plutonium  

SciTech Connect

In this review, volatile coordination and organic compounds of neptunium and plutonium are described, including complex halides, alkoxides, borohydrides, ..beta..-diketonates, phthalocyanines, and organometallic ..pi..-complexes. Comparison is made with analogous compounds of other f-elements (particularly, uranium and thorium). The prospects of practical use of volatile compounds of neptunium and plutonium are discussed.

Mishin, V.Ya.; Sidorenko, G.V.; Suglobov, D.N.

1987-01-01

69

A Systematic Presentation of Organic Phosphorus and Sulfur Compounds.  

ERIC Educational Resources Information Center

|Because the names, interrelations, and oxidation levels of the organic compounds of phosphorus and sulfur tend to confuse students, a simple way to organize these compounds has been developed. The system consists of grouping them by oxidation state and extent of carbon substitution. (JN)|

Hendrickson, James B.

1985-01-01

70

40 CFR 60.462 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.462 Section 60.462 Protection of Environment...Coil Surface Coating § 60.462 Standards for volatile organic compounds. (a) On and after the date on which §...

2013-07-01

71

40 CFR 60.492 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.492 Section 60.492 Protection of Environment...Surface Coating Industry § 60.492 Standards for volatile organic compounds. On or after the date on which the...

2013-07-01

72

40 CFR 60.602 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.602 Section 60.602 Protection of Environment...Production Facilities § 60.602 Standard for volatile organic compounds. On and after the date on which the...

2013-07-01

73

40 CFR 60.432 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.432 Section 60.432 Protection of Environment...Publication Rotogravure Printing § 60.432 Standard for volatile organic compounds. During the period of the performance test...

2013-07-01

74

40 CFR 60.392 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.392 Section 60.392 Protection of Environment...Surface Coating Operations § 60.392 Standards for volatile organic compounds. On and after the date on which the...

2013-07-01

75

40 CFR 60.712 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.712 Section 60.712 Protection of Environment...Tape Coating Facilities § 60.712 Standards for volatile organic compounds. Each owner or operator of any...

2013-07-01

76

40 CFR 60.452 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.452 Section 60.452 Protection of Environment...Coating: Large Appliances § 60.452 Standard for volatile organic compounds. On or after the date on which the...

2013-07-01

77

40 CFR 60.742 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.742 Section 60.742 Protection of Environment...Substrates Facilities § 60.742 Standards for volatile organic compounds. (a) Each owner or operator of an...

2013-07-01

78

40 CFR 60.442 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.442 Section 60.442 Protection of Environment...Surface Coating Operations § 60.442 Standard for volatile organic compounds. (a) On and after the date on which the...

2013-07-01

79

40 CFR 60.582 - Standard for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standard for volatile organic compounds. 60.582 Section 60.582 Protection of Environment...Urethane Coating and Printing § 60.582 Standard for volatile organic compounds. (a) On and after the date on which the...

2013-07-01

80

40 CFR 60.622 - Standards for volatile organic compounds.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standards for volatile organic compounds. 60.622 Section 60.622 Protection of Environment...Petroleum Dry Cleaners § 60.622 Standards for volatile organic compounds. (a) Each affected petroleum solvent...

2013-07-01

81

Organic--Inorganic Layer Compounds: Physical Properties and Chemical Reactions  

Microsoft Academic Search

In contrast with intercalation compounds, which can exist both with and without organic molecules between the planes of inorganic material, `molecular composite' compounds have organic groups covalently or ionically bound to inorganic layers. In such crystals the aim is to combine magnetic or optical properties characteristic of the inorganic solid state, like magnetism and luminescence, with properties found in the

P. Day

1985-01-01

82

DYNAMIC ANALYSIS OF SORPTION OF VOLATILE ORGANIC COMPOUNDS IN WATER  

Microsoft Academic Search

Chlorinated and brominated volatile organic compounds are among the groundwater pollutants creating major environmental problems. In this study, dynamic behavior of certain volatile organic compounds in water was investigated by using a novel moment technique. Adsorption equilibrium constant and the penetration length of tracers were evaluated by the first absolute and the second central moment expressions derived for a pulse-response

Nail Yasyerli; Ugur Harbili

2008-01-01

83

Prioritizing testing of organic compounds detected as gas phase air pollutants: structure-activity study for human contact allergens.  

PubMed Central

Organic compounds that are used or generated anthropogenically in large quantities in cities can be identified through their presence in the urban atmosphere and in air pollutant source emissions. Compounds identified by this method were screened to evaluate their potential to act as contact allergens. The CASE and MULTICASE computer programs, which are based on the detection of structure-activity relationships (SAR), were used to evaluate this potential. These relationships first are determined by comparing chemical structures to biological activity within a learning set comprised of 458 compounds, each of which had been tested experimentally in human trials for its sensitization potential. Using the information contained in this learning set, CASE and MULTICASE predicted the activity of 238 compounds found in the atmosphere for their ability to act as contact allergens. The analysis finds that 21 of 238 compounds are predicted to be active contact allergens (probability >0.5), with potencies ranging from mild to very strong. The compounds come from chemical classes that include chlorinated aromatics and chlorinated hydrocarbons, N-containing compounds, phenols, alkenes, and an S-containing compound. Using the measured airborne concentrations or emission rates of these compounds as an indication of the extent of their use, together with their predicted potencies, provides an efficient method to prioritize the experimental assessment of contact sensitization of untested organic compounds that can be detected as air pollutants. Images Figure 1.

Johnson, R; Macina, O T; Graham, C; Rosenkranz, H S; Cass, G R; Karol, M H

1997-01-01

84

FIELD SCREENING FOR HALOGENATED VOLATILE ORGANIC COMPOUNDS  

SciTech Connect

Western Research Institute (WRI) is continuing work toward the development of new 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 halogens. In prior work, the devices were tested for response to carbon tetrachloride, heptane, toluene, and water vapors. In the current work, sensor response was evaluated with sixteen halogenated VOCs relative to carbon tetrachloride. The results show that the response of the various chlorinated VOCs is within an order of magnitude of the response to carbon tetrachloride for each of the sensors. Thus, for field screening a single response factor can be used. Both types of leak detectors are being further modified to provide an on-board LCD signal readout, which is related to VOC concentration. The units will be fully portable and will operate with 115-V line or battery power. Signal background, noise level, and response data on the Bacharach heated diode detector and the TIF corona discharge detector show that when the response curves are plotted against the log of concentration, the plot is linear to the upper limit for the particular unit, with some curvature at lower levels. When response is plotted directly against concentration, the response is linear at the low end and is curved at the high end. The dynamic ranges for carbon tetrachloride of the two devices from the lower detection limit (S/N=2) to signal saturation are 4-850 vapor parts per million (vppm) for the corona discharge unit and 0.01-70 vppm for the heated diode unit. Additional circuit modifications are being made to lower the detection limit and increase the dynamic response range of the corona discharge unit. The results indicate that both devices show potential utility for future analytical method development work toward the goal of developing a portable test kit for screening halogenated VOCs in the field.

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

2003-07-01

85

Biorestoration of aquifers contaminated with organic compounds  

Microsoft Academic Search

Several forms of biological treatment can be used to treat contaminated aquifers. In situ treatment increases the activity of the indigenous organisms by the addition of nutrients and electron acceptor. Withdrawal and treatment technologies rely on removal of the ground water and any of several wastewater treatment processes to biodegrade the organics. Addition of acclimated or genetically engineered organisms may

M. D. Lee; J. M. Thomas; R. C. Borden; P. B. Bedient; C. H. Ward; J. T. Wilson; R. A. Conway

1988-01-01

86

Radioiodine Volatilization in the Presence of Organic Compounds  

SciTech Connect

The impact of organic compounds on iodine volatility was investigated under a range of postaccident chemical conditions expected in a reactor containment structure. The rate of production of volatile iodine was evaluated in the presence of 10{sup -3} M concentrations of carbonyl, alkyl halide, and aromatic compounds. A bench-scale apparatus, installed in the irradiation chamber of a Gammacell, was used to measure the rate of iodine volatilization from 10{sup -6} to 10{sup -4} M CsI solutions with pH values from 5 to 9. The results indicated that organic compounds could be classified into groups, based on their distinct effects on iodine volatility. Iodine volatilization increased significantly, up to two orders of magnitude, in the presence of carbonyl compounds and alkyl chlorides, while it decreased in the presence of aromatic compounds. Gas phase speciation indicated that organic iodides dominate the airborne iodine species in the presence of carbonyl compounds and alkyl halides.

Taghipour, Fariborz; Evans, Greg J. [University of Toronto (Canada)

2001-05-15

87

Extended structures and physicochemical properties of uranyl-organic compounds.  

PubMed

The ability of uranium to undergo nuclear fission has been exploited primarily to manufacture nuclear weapons and to generate nuclear power. Outside of its nuclear physics, uranium also exhibits rich chemistry, and it forms various compounds with other elements. Among the uranium-bearing compounds, those with a uranium oxidation state of +6 are most common and a particular structural unit, uranyl UO(2)(2+) is usually involved in these hexavalent uranium compounds. Apart from forming solids with inorganic ions, the uranyl unit also bonds to organic molecules to generate uranyl-organic coordination materials. If appropriate reaction conditions are employed, uranyl-organic extended structures (1-D chains, 2-D layers, and 3-D frameworks) can be obtained. Research on uranyl-organic compounds with extended structures allows for the exploration of their rich structural chemistry, and such studies also point to potential applications such as in materials that could facilitate nuclear waste disposal. In this Account, we describe the structural features of uranyl-organic compounds and efforts to synthesize uranyl-organic compounds with desired structures. We address strategies to construct 3-D uranyl-organic frameworks through rational selection of organic ligands and the incorporation of heteroatoms. The UO(2)(2+) species with inactive U?O double bonds usually form bipyramidal polyhedral structures with ligands coordinated at the equatorial positions, and these polyhedra act as primary building units (PBUs) for the construction of uranyl-organic compounds. The geometry of the uranyl ions and the steric arrangements and functionalities of organic ligands can be exploited in the the design of uranyl--organic extended structures, We also focus on the investigation of the promising physicochemical properties of uranyl-organic compounds. Uranyl-organic materials with an extended structure may exhibit attractive properties, such as photoluminescence, photocatalysis, photocurrent, and photovoltaic responses. In particular, the intriguing, visible-light photocatalytic activities of uranyl-organic compounds are potentially applicable in decomposition of organic pollutants and in water-splitting with the irradiation of solar light. We ascribe the photochemical properties of uranyl-organic compounds to the electronic transitions within the U?O bonds, which may be affected by the presence of organic ligands. PMID:21612214

Wang, Kai-Xue; Chen, Jie-Sheng

2011-05-25

88

MICROBIAL TRANSFORMATION KINETICS OF ORGANIC COMPOUNDS  

EPA Science Inventory

One process determining the fate of xenobiotics (organics not natural to a system) in environmental waters is bacterial transformation. Bacteria are one of the most metabolically active groups of organisms in the environment. They can degrade and derive energy from a variety of o...

89

Early diagenetic alterations of biogenetic organic compounds  

Microsoft Academic Search

Plant matter from a beech forest, leaves, and soil were extracted and analyzed by GC-MS technique. The amount of the extract varies with the CPI value. Characteristic compounds like phytadienes, plant alcohols, polycyclic aromatics, sterols, and triterpenes are observed in different samples at various concentrations. It seems there is a rapid change in the composition of extracts from recent plant

A. Hollerbach; Lehrstuhl ffir Geologie

1978-01-01

90

BIODEGRADABILITY STUDIES WITH ORGANIC PRIORITY POLLUTANT COMPOUNDS  

EPA Science Inventory

Ninty-six organic priority pollutants (from EPA Effluent Guidelines Consent Decree) were studied to determine the extent and rate of microbial degradation and the acclimation periods needed for substrate biooxidation. The pollutants have been classified into groups with character...

91

[Emission volatile organic compounds from new textile floor coverings].  

PubMed

The emission of formaldehyde and the other volatile organic compounds (toluene, styrene, 4-PC) and total volatile organic compounds (VOCs) from new textile floor coverings was measured with the use of environmental chamber (0.6 m3 capacity) in the following conditions: temperature 23 degrees C, relative humidity 45%, 1 exchange/hour and factor loading 1 m2 m-3. The formaldehyde was determined by using colorimetric method, VOCs by GC method. The tested carpets did not emit formaldehyde. The emission of other volatile organic compounds was very low and fulfill known requirements. PMID:12621886

Igielska, Barbara; Pecka, Irena; Sitko, Elzbieta; Nikel, Grazyna; Wiglusz, Renata

2002-01-01

92

Natural production of organic bromine compounds in Berlin Lakes.  

PubMed

Berlin surface waters are characterized by elevated concentrations of organic bound bromine (up to 35 microg/L) in late summer. Organic bromine compounds in lakes are of significant importance because human life is closely connected to fresh water. Apart from recreational use, fresh water is frequently used for the production of drinking water, e.g., after bank filtration. Therefore the source, particularly the mechanism responsible for the formation is studied. Field studies indicate that the organic bromine compounds, measured as adsorbable organic bromine (AOBr), are autochthonous. Staggered maxima concentrations of chlorophyll-a, DOC and AOBr indicate that phototrophic organisms might contribute to the AOBr after death. The involvement of phototrophic organisms was established in the laboratory using surface water and/or cultures of organisms. Light and the presence of phototrophic organisms are essential for an AOBr production. Phototrophic organisms incorporate bromide, which is released randomly and after cell death. A part of the incorporated bromide is used for the formation of organic bromine compounds in the cell. After death of the organisms the brominated compounds and the incorporated bromide are released into the water phase, and an extracellular AOBr production can lead to a further formation of AOBr, most probably due to the parallel release of haloperoxidases. PMID:17547185

Hütteroth, Alexandra; Putschew, Anke; Jekel, Martin

2007-05-15

93

Concentration of Organic Compounds in Water. A Literature Survey.  

National Technical Information Service (NTIS)

Because of the large variety of chemical compounds present either naturally or as industrial contaminants in water samples, no single concentration method currently available is adequate for concentrating all organics in the water sample. Consequently, in...

R. L. Jolley

1980-01-01

94

MEASUREMENT OF VAPOR PHASE ORGANIC COMPOUNDS AT HIGH CONCENTRATIONS  

EPA Science Inventory

Laboratory, industrial, chemical, or other waste products may have constituents that evolve volatile organic compounds (VOCS) at very high concentrations. hese could pose human health risks during handling, storage, and disposal of the waste through inhalation, dermal exposure, o...

95

SEPARATION OF VOLATILE ORGANIC COMPOUNDS FROM SURFACTANT SOLUTIONS BY PERVAPORATION  

EPA Science Inventory

Pervaporation is gradually becoming an accepted and practical method for the recovery of volatile organic compounds (VOCs) from aqueous process and waste streams. As the technolog has matured, new applications for pervaporation have emerged. One such application is the separati...

96

GLOBAL INVENTORY OF VOLATILE ORGANIC COMPOUND EMISSIONS FROM ANTHROPOGENIC SOURCES  

EPA Science Inventory

The paper discusses the development of a global inventory of anthropogenic volatile organic compound (VOC) emissions. t includes VOC estimates for seven classes of VOCs: paraffins, olefins, aromatics (benzene, toluene, xylene), formaldehyde, other aldehydes, other aromatics, and ...

97

SYNTHESIZING ORGANIC COMPOUNDS USING LIGHT-ACTIVATED TIO2  

EPA Science Inventory

High-value organic compounds have been synthesized successfully from linear and cyclic hydrocarbons, by photocatalytic oxidation using a semiconductor material, titanium dioxide (TiO2). Various hydrocarbons were partially oxgenated in both liquid and gaseous phase reactors usi...

98

TREATABILITY OF CARCINOGENIC AND OTHER HAZARDOUS ORGANIC COMPOUNDS  

EPA Science Inventory

This research program was conducted to determine the capability of biological and physical-chemical treatment processes to remove chemical carcinogens and other hazardous organic compounds from water and wastewater. Treatment processes investigated included biological degradation...

99

DEVELOPMENT OF OZONE REACTIVITY SCALES FOR VOLATILE ORGANIC COMPOUNDS  

EPA Science Inventory

Methods for developing a numerical scale ranking reactivities of volatile organic compounds (VOCs) towards ozone formation were investigated. ffects of small VOC additions on ozone formation (incremental reactivities) were calculated for 140 types of VOCs in model scenarios repre...

100

METHODS FOR LEVEL 2 ANALYSIS BY ORGANIC COMPOUND CATEGORY  

EPA Science Inventory

The report gives Level 2 procedures, including results of a laboratory evaluation of detailed methods for analyzing organic chemicals in particular compound categories. The report, supplementing an earlier Level 2 procedures manual, provides an initial experimental data base as a...

101

ESTIMATION OF PHYSIOCHEMICAL PROPERTIES OF ORGANIC COMPOUNDS BY SPARC  

EPA Science Inventory

The computer program SPARC (SPARC Performs Automated Reasoning in Chemistry) has been under development for several years to estimate physical properties and chemical reactivity parameters of organic compounds strictly from molecular structure. SPARC uses computational algorithms...

102

Collaborative Study of Soils Spiked with Volatile Organic Compounds.  

National Technical Information Service (NTIS)

Vapor fortification is a method of spiking soils with volatile organic compounds (VOCs) that was recently developed for producing materials suitable for performance evaluation and quality assurance/quality control (QA/QC). Using this treatment method, soi...

A. D. Hewitt C. L. Grant

1995-01-01

103

COMPACT, CONTINUOUS MONITORING FOR VOLATILE ORGANIC COMPOUNDS - PHASE I  

EPA Science Inventory

Improved methods for onsite measurement of multiple volatile organic compounds are needed for process control, monitoring, and remediation. This Phase I SBIR project sets forth an optical measurement method that meets these needs. The proposed approach provides an instantaneous m...

104

CHARACTERIZATION OF VOLATILE ORGANIC COMPOUNDS IN AIRBORNE DUST  

Technology Transfer Automated Retrieval System (TEKTRAN)

Three methods of extracting volatile organic compounds (VOC's) adsorbed on the airborne dust in a swine finishing building were investigated. Airborne dust was collected in pre-baked glass fiber filters (GFF's) and the compounds were extracted by solvent extraction using dichloromethane, solid phas...

105

DESTRUCTION OF VOLATILE ORGANIC COMPOUNDS VIA CATALYTIC INCINERATION  

EPA Science Inventory

The paper gives results of an investigation of the effect of catalytic incinerator design and operation the destruction of specific volatile organic compounds (VOCs), both singly and in mixtures. A range of operating and design parameters were tested on a wide variety of compound...

106

MASS SPECTRA OF SOME ORGANIC AND INORGANIC COMPOUNDS  

Microsoft Academic Search

A compilation was made of some mass spectra of various organic and ; inorganic compounds which are not listed in previous compilations of mass ; spectral data. These compounds were collected from various sources, and many are ; the result of syntheses in the University of California Chemistry Department or ; the Lawrence Radiation Laboratory. All have appreciable vapor pressures

A. S. Newton; S. J. Waters

1959-01-01

107

Radiocarbon dating of diatom-bound organic compounds  

Microsoft Academic Search

Here we present a new method for obtaining radiocarbon dates for the organic compounds intrinsic to diatom frustules. This method will improve age models for sediment cores that lack calcium carbonate and improve current interpretations of diatom-based paleoproxies. In preparation for radiocarbon dating by Accelerator Mass Spectrometry, compounds intrinsic to diatom frustules are released from their opal matrix by dissolution

Anitra E. Ingalls; Robert F. Anderson; Ann Pearson

2004-01-01

108

Octanol-Water Partition Coefficients of Simple Organic Compounds  

Microsoft Academic Search

Octanol-water partition coefficients (log P) for 611 simple organic compounds representing all principal classes have been retrieved from the literature. Available experimental details of measurement are documented from original articles. Pertinent thermodynamic relations are presented, with a discussion of direct and indirect methods of measurement. Reported log P data for each compound have been evaluated according to stated criteria, and

James Sangster

1989-01-01

109

Novel Organic-Inorganic Hybrid Compounds Containing Alkyldiammonium Salts  

Microsoft Academic Search

Novel organic-inorganic hybrid compounds, C n N 2 PbBr 4 (n=4,6,8 and 10) and C 2 N 2 PbBr 4 · DMSO, were prepared by the self-organization of lead bromide and a variety of alkyldiammonium cations. The powder X-ray diffraction patterns of C n N 2 PbBr 4 demonstrated that the compounds form layered perovskite structures and the interlayer spacing

Takashi Matsui; Mitsuyasu Kawahara; Kenjiro Teshima; Masahiro Rikukawa; Kohei Sanui

2002-01-01

110

Geosynthesis of organic compounds: I. Alkylphenols  

NASA Astrophysics Data System (ADS)

Methylation, isopropylation, and sec-butylation are proposed as geosynthetic processes to account for the alkylphenol compositions of crude oils with phenol distributions dominated by ortho and para substituted compounds. Phenol distributions in eleven crude oils and four kerogen pyrolysates were analysed using GC-MS (gas chromatography-mass spectrometry). Ten of the crude oils show high relative abundances of ortho and para substituted phenol isomers and some were also enriched in C 3-C 5 alkylphenols compared to the kerogen pyrolysates. Because the distributions of products obtained from the laboratory alkylation of cresols closely resemble those of phenols in these crude oils, we propose that similar alkylation processes occur in source rocks. Alkylation ratios reflecting the degree of methylation, isopropylation, and sec-butylation, which were based on the relative abundance of the dominant alkylation products compared to their likely precursor ortho-cresol, indicate that high levels of methylation occurred in crude oils over a wide range of maturities, whereas high levels of isopropylation and sec-butylation were observed only in mature samples. Dissolution of the phenols in crude oils by water contact was discounted as an explanation for the observed phenol distributions based on the relative distribution coefficients of phenols between a hydrocarbon phase and water.

Ioppolo-Armanios, Marisa; Alexander, Robert; Kagi, Robert I.

1995-07-01

111

Analysis of volatile organic compounds from illicit cocaine samples  

SciTech Connect

Detection of illicit cocaine hydrochloride shipments can be improved if there is a greater understanding of the identity and quantity of volatile compounds present. This study provides preliminary data concerning the volatile organic compounds detected in a limited Set of cocaine hydrochloride samples. In all cases, cocaine was one of the major volatile compounds detected. Other tropeines were detected in almost all samples. Low concentrations of compounds that may be residues of processing solvents were observed in some samples. The equilibrium emissivity of. cocaine from cocaine hydrochloride was investigated and a value of 83 parts-per-trillion was determined.

Robins, W.H.; Wright, B.W.

1994-07-01

112

Rejection of trace organic compounds by high-pressure membranes.  

PubMed

High-pressure membranes, encompassing reverse osmosis (RO), nanofiltration (NF), and low-pressure RO, may provide an effective treatment barrier for trace organic compounds including disinfection by-products (DBPs), pesticides, solvents, endocrine disrupting compounds (EDCs) and pharmaceutically active compounds (PhACs). The objective is to develop a mechanistic understanding of the rejection of trace organic compounds by high-pressure membranes, based on an integrated framework of compound properties, membrane properties, and operational conditions. Eight trace organic compounds, four DBPs and four chlorinated (halogenated) solvents, are being emphasized during an initial study, based on considerations of compound properties, occurrence, and health effects (regulations). Four polyamide FilmTec membranes; three reverse osmosis/RO (BW-400, LE-440, XLE-440) and one nanofiltration/NF (NF-90); are being characterized according to pure water permeability (PWP), molecular weight cutoff (MWCO), hydrophobicity (contact angle), and surface charge (zeta potential). It is noteworthy that rejections of compounds of intermediate hydrophobicity by the candidate membranes were observed to be less than salt rejections reported for these membranes, suggesting that transport of these solutes through these membranes is facilitated by solute-membrane interactions. We are continuing with diffusion cell measurements to describe solute-membrane interactions by estimation of diffusion coefficients through membranes pores, either hindered or facilitated. PMID:16003994

Kim, T U; Amy, G; Drewes, J E

2005-01-01

113

COMPARISON OF AMBIENT AIR SAMPLING TECHNIQUES FOR VOLATILE ORGANIC COMPOUNDS  

EPA Science Inventory

A series of fourteen experimental sampling runs were carried out at a field site to collect data from several ambient air monitoring methods for volatile organic compounds (VOCs). Ambient air was drawn through a sampling manifold and was continuously spiked with volatile organic ...

114

Chemical reactions of organic compounds on clay surfaces  

SciTech Connect

Chemical reactions of organic compounds including pesticides at the interlayer and exterior surfaces of clay minerals and with soil organic matter are reviewed. Representative reactions under moderate conditions possibly occurring in natural soils are described. Attempts have been made to clarify the importance of the chemical nature of molecules, their structures and their functional groups, and the Broensted or Lewis acidity of clay minerals.

Soma, Yuko; Soma, Mitsuyuki (National Institute for Environmental Studies, Ibaraki (Japan))

1989-11-01

115

Chemical reactions of organic compounds on clay surfaces.  

PubMed Central

Chemical reactions of organic compounds including pesticides at the interlayer and exterior surfaces of clay minerals and with soil organic matter are reviewed. Representative reactions under moderate conditions possibly occurring in natural soils are described. Attempts have been made to clarify the importance of the chemical nature of molecules, their structures and their functional groups, and the Brönsted or Lewis acidity of clay minerals.

Soma, Y; Soma, M

1989-01-01

116

Organic sulfur compounds in crude oils of West Kazakhstan  

Microsoft Academic Search

This article reports on a study of the distribution of organic sulfur compounds (mercaptans, disulfides, and sulfides) in crude oils and in 50°C cuts, and also in gas condensates. Notes that the crude oils of West Kazakhstan, particularly the field that have been discovered recently, are extremely diverse in physiochemical properties, particularly in their content and structure of organic sulfur

V. V. Ryzhenko; N. S. Buyanova; A. V. Kotova; N. K. Nadirov

1983-01-01

117

INTERACTIONS BETWEEN ORGANIC COMPOUNDS AND CYCLODEXTRIN-CLAY SYSTEMS  

EPA Science Inventory

Computational and experimental techniques are combined in order to better understand interactions involving organic compounds and cyclodextrin (CD)-clay systems. CD-clay systems may have great potential in the containment of organic contaminants in the environment. This study w...

118

BIOCONCENTRATION FACTORS FOR VOLATILE ORGANIC COMPOUNDS IN VEGETATION  

EPA Science Inventory

Samples of air and leaves were taken at the University of Nevada-Las Vegas campus and analyzed for volatile organic compounds using vacuum distillation coupled with gas chromatography/mass spectrometry. The data were used to estimate the bioconcentration of volatile organic compo...

119

[Methods for the assessment of organic compounds biodegradability: A review].  

PubMed

There are plenty of methods used for the assessment of organic compounds biodegradability, but lack of comprehensive literatures in systematically introducing the assessment methods and guiding the choice of the methods. This paper briefly introduced the indicative parameters in assessing organic compounds biodegradability and the assessment methods of aerobic and anaerobic biodegradation, with the focus on the principles and criteria in the choice of the assessment methods, and analyzed in detail the reasons for the differences in the biodegradation rates of organic compounds when different test methods were adopted. Taking the standards established by the Organization for Economic Co-operation and Development (OECD) as an example, the process of choosing and applying the assessment methods was introduced, the systematic method-choosing route was integrated, and the advantages of the OECD standard methods were pointed out. PMID:23705410

Lu, Kang; Yang, Shang-Yuan; Liang, Zhi-Wei; Wang, Yun-Long; Li, Xin; Yu, Hua-Dong; Wu, Wei-Xiang

2013-02-01

120

Thermal decomposition studies of halogenated organic compounds  

SciTech Connect

Thermal decomposition results for CCl{sub 4}, CHCl{sub 3}, CH{sub 2}Cl{sub 2}, CH{sub 3}Cl, C{sub 3}H{sub 3}Cl, CFCl{sub 3}, CF{sub 2}Cl{sub 2}, CF{sub 3}Cl, CF{sub 2}HCl, CF{sub 3}I, CH{sub 3}I, C{sub 2}H{sub 5}I, C{sub 6}H{sub 5}I, and CCl{sub 2}O are presented. The results were obtained by shock tube techniques coupled with optical spectroscopic detection of transient species formed from dissociation. The method is illustrated with the CH{sub 3}I (+ Kr) {yields} CH{sub 3} + I (+ Kr) reaction where decomposition was monitored using I-atomic resonance absorption spectrometry (ARAS). Modern unimolecular rate theoretical analysis has been carried out on the present cases, and the conclusions from these calculations are discussed. Lastly, the possible destruction of halo-organics by incineration is considered and some implications are discussed.

Michael, J.V.; Kumaran, S.S.

1997-06-01

121

77 FR 46961 - Approval and Promulgation of Implementation Plans; Wisconsin; Volatile Organic Compound Emission...  

Federal Register 2010, 2011, 2012, 2013

...Implementation Plans; Wisconsin; Volatile Organic Compound Emission Control Measures for...Technology (RACT) for sources of Volatile Organic Compound (VOC) emissions in moderate...recordkeeping requirements, Volatile organic compounds. Dated: June 11, 2012....

2012-08-07

122

Emission of volatile organic compounds to the atmosphere in the solvent sublation process. II. Volatile chlorinated organic compounds  

SciTech Connect

The mass of trichloroethylene, chlorobenzene, and 1,3-dichlorobenzene removed from an aqueous solution and emitted to the atmosphere during solvent sublation was determined experimentally. It was shown that the emission of these compounds in solvent sublation was reduced by 30 to 85% over air stripping under the same experimental conditions. The efficiency of removal of these compounds from water was also studied. The reduction of emissions over air stripping was more effective for the more hydrophobic and less volatile compounds. Emissions are reduced as the thickness of organic layer on the top of the column is increased. The use of decyl alcohol as the layer compound decreases emissions to a greater extent than does paraffin oil. Removal of these chlorinated volatile organic compounds from water by solvent sublation at an elevated temperature of 45{degrees}C is significantly faster than at room temperature. However, the emissions to the atmosphere are also increased.

Ososkov, V.; Kebbekus, B.; Chou, C.C. [New Jersey Inst. of Technology, Newark, NJ (United States)

1996-06-01

123

Volatile organic compounds in Gulf of Mexico sediments  

SciTech Connect

Volatile organic compounds (VOC), concentrations and compositions were documented for estuarine, coastal, shelf, slope, and deep water sediments from the Gulf of Mexico. VOC were measured (detection limit >0.01 ppb) using a closed-loop stripping apparatus with gas chromatography (GC) and flame ionization, flame photometric, and mass spectrometric detectors. The five primary sources of Gulf of Mexico sediment VOC are: (1) planktonic and benthic fauna and flora; (2) terrestrial material from riverine and atmospheric deposition; (3) anthropogenic inputs: (4) upward migration of hydrocarbons; and (5) transport by bottom currents or slumping. Detected organo-sulfur compounds include alkylated sulfides, thiophene, alkylated thiophenes, and benzothiophenes. Benzothiophenes are petroleum related. Low molecular weight organo-sulfur compounds result from the biological oxidation of organic matter. A lack of organosulfur compounds in the reducing environment of the Orca Basin may result from a lack of free sulfides which are necessary for their production.

McDonald, T.J.

1988-01-01

124

Photosynthetic marine organisms as a source of anticancer compounds  

Microsoft Academic Search

Since early human history, plants have served as the most important source of medicinal natural products, and even in the\\u000a “synthetic age” the majority of lead compounds for pharmaceutical development remain of plant origin. In the marine realm,\\u000a algae and seagrasses were amongst the first organisms investigated by marine natural products scientists on their quest for\\u000a novel pharmaceutical compounds. Forty

F. Folmer; M. Jaspars; M. Dicato; M. Diederich

2010-01-01

125

Adsorption Selectivity of FSM-16 for Several Organic Compounds  

Microsoft Academic Search

A folded-sheet mesoporous material (FSM-16) was prepared, and its adsorption selectivity for several organic compounds (p-nitrophenol, toluene, n-heptane, benzene, cyclohexane, and o-dichlorobenzene) was studied. The adsorbed amounts of these compounds were measured by batch operation in liquid phase. The p-nitrophenol in aqueous solution was hardly adsorbed into FSM-16, but toluene (in n-heptane solvent) and benzene (in n-heptane solvent or cyclohexane

Masahiro Katoh; Hitoshi Takao; Naoto Abe; Tahei Tomida

2001-01-01

126

Transformation of certain organic compounds on exhaustive oxidation catalysts  

Microsoft Academic Search

The authors studied the role of water in vapor-phase catalytic oxidation. Two catalysts and three organic compounds of different chemical natures - formic acid, 4,4-dimethyl-1,3-dioxane, and isopropanol - were used as examples, and it was shown that water vapor does not hinder the vapor-phase transformations of these compounds at the intermediate stages of exhaustive catalytic oxidation during dehydrogenation and dehydration.

E. V. Kuznetsova; S. V. Zubarev; V. V. Ivanova; L. N. Karazeeva; S. A. Taranenko

1988-01-01

127

SDBS: Integrated Spectral Data Base System for Organic Compounds  

NSDL National Science Digital Library

Provided by Agency of Industrial Science and Technology of Japan, the Integrated Spectral Data Base System for Organic Compounds is a database of mass spectral, NMR (proton and carbon), and infrared spectra data. As of March 1999, the database contains 19,600 spectra of MS, 11,000 spectra of ^13 C NMR, 13,500 spectra of ^1 H NMR, 2,000 spectra of ESR, 47,500 spectra of IR, 3,500 spectra of Raman, and 30,000 compounds in the Compound Dictionary. A search engine (Frames) for the database allows the following fields to be specified: Compound Name, Molecular Formula, Number of Atoms (Carbon, Hydrogen, Oxygen, and Nitrogen), Molecular Weight, CAS Registry Number, and SDBS Number. Access is free; however, no more than 50 spectra and/or compound files may be downloaded in one day.

128

Bioconcentration factors for volatile organic compounds in vegetation.  

PubMed

Samples of air and leaves were taken at the University of Nevada [Formula: see text] Las Vegas campus and analyzed for volatile organic compounds using vacuum distillation coupled with gas chromatography/mass spectrometry. The data were used to estimate the bioconcentration of volatile organic compounds (VOCs) and to characterize the equilibration of VOCs between the leaves and air. The bioconcentration of volatiles in the leaves of some species can be predicted using the partition coefficients between air and octanol (K(oa)) and only considering VOC absorption in the lipid fraction of leaves. For these leaves, the bioconcentration factors agreed with existing models. Leaves of some species displayed a bioconcentration of volatiles that greatly exceeded theory. These hyperbioconcentration leaves also contain appreciable concentrations of monoterpenes, suggesting that a terpenoid compartment should be considered for the bioconcentration of organic compounds in leaves. Adding an additional "terpenoid" compartment should improve the characterization of volatile organic compounds in the environment. The uptake of VOCs from air by leaves is rapid, and the equilibration rates are seen to be quicker for compounds that have higher vapor pressures. The release of VOCs from the leaves of plants is slower for hyperbioconcentration leaves. PMID:21644617

Hiatt, M H

1998-03-01

129

Emissions and Secondary Organic Aerosol Production from Semivolatile and Intermediate Volatility Organic Compounds  

Microsoft Academic Search

Organic aerosols are a highly-dynamic system dominated by both variable gas-particle partitioning and chemical evolution. Important classes of organics include semivolatile and intermediate volatility organic compounds (SVOC and IVOC, respectively). SVOCs are compounds that exist in both the gas and particle phases at typical atmospheric conditions while IVOC are low-volatility vapors that exist exclusively in the gas phase. Both classes

A. L. Robinson; A. A. Presto; M. A. Miracolo; N. M. Donahue; J. H. Kroll; D. R. Worsnop

2008-01-01

130

Dosimeter for monitoring vapors and aerosols of organic compounds  

DOEpatents

A dosimeter is provided for collecting and detecting vapors and aerosols of organic compounds. The dosimeter comprises a lightweight, passive device that can be conveniently worn by a person as a badge or placed at a stationary location. The dosimeter includes a sample collector comprising a porous web treated with a chemical for inducing molecular displacement and enhancing phosphorescence. Compounds are collected onto the web by molecular diffusion. The web also serves as the sample medium for detecting the compounds by a room temperature phosphorescence technique. 7 figs.

Vo-Dinh, T.

1987-07-14

131

Dosimeter for monitoring vapors and aerosols of organic compounds  

DOEpatents

A dosimeter is provided for collecting and detecting vapors and aerosols of organic compounds. The dosimeter comprises a lightweight, passive device that can be conveniently worn by a person as a badge or placed at a stationary location. The dosimeter includes a sample collector comprising a porous web treated with a chemical for inducing molecular displacement and enhancing phosphorescence. Compounds are collected onto the web by molecular diffusion. The web also serves as the sample medium for detecting the compounds by a room temperature phosphorescence technique.

Vo-Dinh, Tuan (625 Gulfwood Rd., Knoxville, TN 37923)

1987-01-01

132

Raman scattering studies of organic semiconducting charge-transfer compounds  

NASA Astrophysics Data System (ADS)

Organic semiconductors offer the possibility of devices with greater mechanical flexibility and lower production costs compared to existing materials. Reports of carrier mobilities in monomolecular organic semiconductors in the 10-50 cm^2/V-s range and success in fabricating electronic devices from organic materials has increased the interest in their properties for electronic applications. However, the range of properties displayed by the monomolecular crystals is rather narrow. Charge-transfer compounds composed of two different organic molecules in which one acts as a donor and the other as an acceptor may represent the next generation of organic semiconductors. Control of their properties by modification of the molecules or changes in stoichiometry and crystalline structure makes them particularly attractive for a wide range of applications provided that the relationship between the structure and constituents of the compounds and their physical properties can be elucidated. Raman scattering studies of single crystals of two representative charge-transfer compounds, perylene-TCNQ and anthracene-TCNQ, will be presented. Theoretical calculations suggest that these materials have the potential for ambipolar charge transport, and so intermolecular interactions in these compounds are of particular interest.

McNeil, Laurie; Kloc, Christian

2011-03-01

133

Gas chromatographic determination of water in organic compounds and of organic compounds in water after steam distillation  

SciTech Connect

A gas chromatograph (GC) with a flame ionization detector (FID) is shown to be effective in the determination of water in organic compounds. The ketal, 2,2-dimethoxypropane (DMP), reacts quantitatively with water to yield the products methanol and acetone when an acid catalyst is present. A solid acid catalyst, Nafion, has been effective and is easily separated before sample introduction into the GC. Several organic solvents were analyzed using this indirect method for determining water. The method is effective for determining water from 0.001-3.5% w/w. Solid samples were also analyzed and the water found in additional spikes agreed with the amount added. Simple steam distillation is used for the isolation and concentration of organic compounds from water matrices. Organic compounds are spiked into a flask containing water and the mixture is then boiled. Typical distillation times take less than 25 minutes. The condensate is collected in a small collection tube and a portion is injected into a GC containing a capillary column. The recovery of most compounds with boiling points from 77 to 238{degree}C is better than 90% and a concentration effect of ten is realized. Steam distillation combined with solid phase extraction is shown to be effective in isolating and concentrating compounds from water in the part-per-billion range. A simple interface between the boiling apparatus and resin collection column is presented. Once the organic analytes are boiled and collected on the resin, they are removed with a small amount of ethyl acetate. The ethyl acetate solution is then injected into a GC. Compounds with boiling points above 400{degree}C can be determined by turning off the flow of cold water in the condenser. Recoveries are better than 80% for compounds with boiling points between 132 to 404{degree}C.

Dix, K.D.

1989-01-01

134

Partition of Volatile Organic Compounds in Activated Sludge and Wastewater  

Microsoft Academic Search

The Henry’s law constant is important in the gas-liquid mass transfer process. Apparent dimensionless Henry’s law constant, or the gas-liquid partition coefficient (K’H), for both hydrophilic (methanol, isopropyl alcohol, and acetone) and hydrophobic (toluene and p-xylene) organic compounds in deionized (DI) water, a wastewater with a maximum total dissolved organic carbon (DOC) content of 700 mg\\/L, and DI water mixed

Jun-Hong Lin; Ming-Shean Chou

2006-01-01

135

VOC (VOLATILE ORGANIC COMPOUND) FUGITIVE EMISSION PREDICTIVE MODEL - USER'S GUIDE  

EPA Science Inventory

The report discusses a mathematical model that can be used to evaluate the effectiveness of various leak detection and repair (LDAR) programs on controlling volatile organic compound (VOC) fugitive emissions from chemical, petroleum, and other process units. The report also descr...

136

PHOTOTHERMAL DESTRUCTION OF THE VAPOR OF VOLATILE ORGANIC COMPOUNDS  

EPA Science Inventory

The contamination of subsurface soil and groundwater by volatile organic compounds (VOCS) is a pervasive problem in the United States. n-situ soil vapor extraction (SVE) and ex-situ thermal desorption are the most adapted technologies for the remediation of contaminated soil whil...

137

Volatile organic compound emissions from dairy facilities in central California  

Technology Transfer Automated Retrieval System (TEKTRAN)

Emissions of volatile organic compounds (VOCs) from dairy facilities are thought to be an important contributor to high ozone levels in central California, but emissions inventories from these sources contain significant uncertainties. In this work, VOC emissions were measured at two central Califor...

138

MEASUREMENT OF ORGANIC COMPOUND EMISSIONS USING SMALL TEST CHAMBERS  

EPA Science Inventory

Organic compounds emitted from a variety of indoor materials have been measured using small (166 L) environmental test chambers. The paper discusses: a) factors to be considered in small chamber testing; b) parameters to be controlled; c) the types of results obtained. The follow...

139

NATIONAL AMBIENT VOLATILE ORGANIC COMPOUNDS (VOCS) DATA BASE UPDATE, DOCUMENTATION  

EPA Science Inventory

Data on the observed concentrations of three hundred twenty (320) volatile organic compounds (VOCs) were compiled, critically evaluated, and assembled into a relational data base. Ambient (i.e., outdoor) measurements, indoor data, and data collected with personal monitors are inc...

140

LEAVES AS INDICATORS OF EXPOSURE TO AIRBORNE VOLATILE ORGANIC COMPOUNDS  

EPA Science Inventory

The concentration of volatile organic compounds (VOCs) in leaves is primarily a product of airborne exposures and dependent upon bioconcentration factors and release rates. The bioconcentration factors for VOCs in grass are found to be related to their partitioning between octan...

141

AERATION TO REMOVE VOLATILE ORGANIC COMPOUNDS FROM GROUND WATER  

EPA Science Inventory

The interim report presents general information on the use of aeration to remove volatile organic compounds from drinking water for public health reasons. The report illustrates the types of aerators, shows where they are being used, presents a means of estimating aeration perfor...

142

Volatile organic compounds in some urban locations in United States  

Microsoft Academic Search

Volatile organic compounds (VOCs) have been determined to be human risk factors in urban environments, as well as primary contributors to the formation of photochemical oxidants. Ambient air quality measurements of 54 VOCs including hydrocarbons, halogenated hydrocarbons and carbonyls were conducted in or near 13 urban locations in the United States during September 1996 to August 1997. Air samples were

Mahmoud F. Mohamed; Daiwen Kang; Viney P. Aneja

2002-01-01

143

Assessment of volatile organic compound emissions from ecosystems of China  

Microsoft Academic Search

Isoprene, monoterpene, and other volatile organic compound (VOC) emissions from grasslands, shrublands, forests, and peatlands in China were characterized to estimate their regional magnitudes and to compare these emissions with those from landscapes of North America, Europe, and Africa. Ecological and VOC emission sampling was conducted at 52 sites centered in and around major research stations located in seven different

L. F. Klinger; Q.-J. Li; A. B. Guenther; J. P. Greenberg; B. Baker; J.-H. Bai

2002-01-01

144

Removal of Volatile Organic Compounds from polluted air  

Microsoft Academic Search

Volatile Organic Compounds (VOCs) are among the most common air pollutants emitted from chemical, petrochemical, and allied industries. VOCs are one of the main sources of photochemical reaction in the atmosphere leading to various environmental hazards; on the other hand, these VOCs have good commercial value. Growing environmental awareness has put up stringent regulations to control the VOCs emissions. In

Faisal I. Khan; Aloke Kr. Ghoshal

2000-01-01

145

DESTRUCTION OF VOLATILE ORGANIC COMPOUNDS VIA CATALYTIC INCINERATION (JOURNAL VERSION)  

EPA Science Inventory

The paper gives results of an investigation of the effect of catalytic incinerator design and operation on the destruction of specific volatile organic compounds (VOCs), both singly and in mixtures. A range of operating and design parameters were tested on a wide variety of compo...

146

Organic Compounds in Coal-Slurry-Pipeline Waters. Final Report.  

National Technical Information Service (NTIS)

Organic compounds in the water separated from coal pipeline slurry has been investigated on a laboratory basis for the slurry with each of three subbituminous coals: Wyodak, Illinois No. 6 and Black Mesa. The results are compare with results from the Blac...

A. S. Newton H. Villarreal P. J. Fox R. Raval W. Walker

1982-01-01

147

Mass transfer of nonvolatile organic compounds from porous media  

Microsoft Academic Search

This thesis presents data pertaining to the mass transfer of nonvolatile organic compounds from porous media. Physical properties of porous solids, including surface and pore areas, are studied. Information from these studies, along with dissolution data, are used to develop correlations relating the Sherwood Number to the Peclet Number. The contaminant used in this study is naphthalene; the solids used

Crist Simon Khachikian

1999-01-01

148

FIELD EXPERIENCE WITH FOUR PORTABLE VOC (VOLATILE ORGANIC COMPOUND) MONITORS  

EPA Science Inventory

This report discusses the field operation problems associated with use of four portable volatile organic compound (VOC) detection instruments in conducting Reference Method 21 VOC screenings. The report presents the results of the field trials and summarizes the ease of use of ea...

149

Synthesis of tritium-labeled nitrogen-containing organic compounds  

SciTech Connect

Conditions of tritium labeling of certain nitrogen-containing organic compounds have been determined. Combination of isotope exchange or hydrogenation with gaseous tritium and chemical synthesis allowed preparation of N-oleyldihydrosphingosine (I) and spermine with molar radioactivities of 200-210 and 23-25 Ci mmol{sup {minus}1} respectively.

Shevchenko, V.P.; Nagaev, I.Yu.; Potapova, A.V. [Inst. of Molecular Genetics, Moscow (Russian Federation)] [and others

1995-07-01

150

In situ bioremediation of petroleum hydrocarbon and other organic compounds  

Microsoft Academic Search

From supertanker oil spills to the leaking underground storage tank at the corner gas station, contamination from petroleum hydrocarbon fuels and other organic compounds is an environmental concern that affects nearly every small hamlet and major metropolis throughout the world. Moreover, the world`s rivers, estuaries, and oceans are threatened by contamination from petroleum leaks and spills. Fortunately, most petroleum hydrocarbons

B. C. Alleman; A. Leeson

1999-01-01

151

Volatile organic compound emission factors from roadside measurements  

Microsoft Academic Search

Volatile organic compounds (VOCs) play a significant role in the generation of urban photochemical smog. In addition, some VOCs, such as benzene, are harmful to human health. In Japan, motor vehicles are the dominant source of VOCs. Therefore, it is important to determine the emission of VOCs from vehicles in order to estimate human risk and the production mechanisms of

Hiroto Kawashima; Shigeki Minami; Yoshimichi Hanai; Akihiro Fushimi

2006-01-01

152

Qualitative analysis of volatile organic compounds on biochar  

Technology Transfer Automated Retrieval System (TEKTRAN)

Qualitative identification of sorbed volatile organic compounds (VOCs) on biochar was conducted by headspace thermal desorption coupled to capillary gas chromatographic-mass spectrometry. VOCs may have a mechanistic role influencing plant and microbial responses to biochar amendments, since VOCs ca...

153

Modeling emissions of volatile organic compounds from silage  

Technology Transfer Automated Retrieval System (TEKTRAN)

Volatile organic compounds (VOCs), necessary reactants for photochemical smog formation, are emitted from numerous sources. Limited available data suggest that dairy farms emit VOCs with cattle feed, primarily silage, being the primary source. Process-based models of VOC transfer within and from si...

154

Emission and Chemical Transformation of Biogenic Volatile Organic Compounds (echo)  

Microsoft Academic Search

Forests are complex sources of biogenic volatile organic compounds (VOC) in the planetary boundary layer. The impact of biogenic VOC on tropospheric photochem- istry, air quality, and the formation of secondary products affects our climate on a regional and global scale but is far from being understood. A considerable lack of knowledge exists concerning a forest stand as a net

R. Koppmann; T. Hoffmann; J. Kesselmeier; M. Schatzmann

2002-01-01

155

A Review of the Tissue Residue Approach for Organic and Organometallic Compounds in Aquatic Organisms  

EPA Science Inventory

This paper reviews the tissue residue approach (TRA) for toxicity assessment as it applies to organic chemicals and some organometallic compounds (tin, mercury, and lead). Specific emphasis was placed on evaluating key factors that influence interpretation of critical body resid...

156

Analysis of Organic Compounds in Returned Comet Nucleus Samples  

NASA Astrophysics Data System (ADS)

Comets are generally believed to be primitive bodies that preserve solar system matter in, or nearly in, its primordial state. This expectation has been at least partially borne out by the 1986 flyby missions to Comet Halley which provided data indicating that, with the exception of hydrogen, the light elements (C, N, O, and S) occur in approximately their solar abundances. Although mass spectrometers carried aboard the spacecraft provided much additional data from which to speculate about the molecular forms of these elements a detailed understanding of cometary organic chemistry will ultimately require the laboratory examination of returned samples. Some of the problems that will be encountered in such studies, for example, sensitivity to trace constituents, resolution of numerous isomeric forms, and avoidance of terrestrial contaminants, have already been faced in analyses of the organic compounds from carbonaceous chondrites. Furthermore, there is reason to believe that the progenitors of the carbonaceous chondrites were volatile rich planetesimals similar to those which, at greater radial distances, formed comets. Thus, the organic chemistry of carbonaceous chondrites may represent the outcome of a process of chemical evolution that parallels, although is perhaps further advanced than, that which occurred in comets. These meteorites may then represent not only a useful model for the development and refinement of analytical methods, but also a guide to the types of organic compounds that may be encountered in analyses of cometary matter. In this paper, I have (i) briefly reviewed the results of amino acid analyses of CM chondrites, (ii) discussed the origin of these compounds and the implications for comet organic chemistry, and (iii) described some recent developments in analytical instrumentation for amino acids and their implications for analyses of extraterrestrial materials. Although the emphasis is on amino acids, their general characteristics are common to the other classes of organic compounds in CM chondrites and inferences regarding their origins should be generally relevant.

Cronin, John R.

1997-12-01

157

DISTRIBUTION OF HYDROPHOBIC IONOGENIC ORGANIC COMPOUNDS BETWEEN OCTANOL AND WATER: ORGANIC ACIDS  

EPA Science Inventory

The octanol-water distributions of 10 environmentally significant organic acid compounds were determined as a function of aqueous-phase salt concentration (0.05-0.2 M LiCl, NaCl, KCl, CaCl2, or MgCl2) and pH. he compounds were pentachlorophenol 2,3,4,5-tetrachlorophenol, (2,4,5-t...

158

Emission of volatile organic compounds from silage: compounds, sources, and implications  

Technology Transfer Automated Retrieval System (TEKTRAN)

Silage, fermented cattle feed, has recently been identified as a significant source of volatile organic compounds (VOCs) emitted to the atmosphere. A small number of studies have measured VOC emission from silage, but not enough is known about the processes involved to accurately quantify emission r...

159

Natural organic compounds as tracers for biomass combustion in aerosols  

SciTech Connect

Biomass combustion is an important primary source of carbonaceous particles in the global atmosphere. Although various molecular markers have already been proposed for this process, additional specific organic tracers need to be characterized. The injection of natural product organic tracers to smoke occurs primarily by direct volatilization/steam stripping and by thermal alteration based on combustion temperature. The degree of alteration increases as the burn temperature rises and the moisture content of the fuel decreases. Although the molecular composition of organic matter in smoke particles is highly variable, the molecular structures of the tracers are generally source specific. The homologous compound series and biomarkers present in smoke particles are derived directly from plant wax, gum and resin by volatilization and secondarily from pyrolysis of biopolymers, wax, gum and resin. The complexity of the organic components of smoke aerosol is illustrated with examples from controlled burns of temperate and tropical biomass fuels. Burning of biomass from temperate regions (i.e., conifers) yields characteristic tracers from diterpenoids as well as phenolics and other oxygenated species, which are recognizable in urban airsheds. The major organic components of smoke particles from tropical biomass are straight-chain, aliphatic and oxygenated compounds and triterpenoids. The precursor-to-product approach of organic geochemistry can be applied successfully to provide tracers for studying smoke plume chemistry and dispersion.

Simoneit, B.R.T. [Brookhaven National Lab., Upton, NY (United States)]|[Oregon State Univ., Corvallis, OR (United States). Coll. of Oceanic and Atmospheric Sciences; Abas, M.R. bin [Brookhaven National Lab., Upton, NY (United States)]|[Univ. of Malaya, Kuala Lumpur (Malaysia); Cass, G.R. [Brookhaven National Lab., Upton, NY (United States)]|[California Inst. of Tech., Pasadena, CA (United States). Environmental Engineering Science Dept.; Rogge, W.F. [Brookhaven National Lab., Upton, NY (United States)]|[Florida International Univ., University Park, FL (United States). Dept. of Civil and Environmental Engineering; Mazurek, M.A. [Brookhaven National Lab., Upton, NY (United States); Standley, L.J. [Academy of Natural Sciences, Avondale, PA (United States). Stroud Water Research Center; Hildemann, L.M. [Stanford Univ., CA (United States). Dept. of Civil Engineering

1995-08-01

160

78 FR 24990 - Approval and Promulgation of Implementation Plans; Ohio; Volatile Organic Compound Emission...  

Federal Register 2010, 2011, 2012, 2013

...Implementation Plans; Ohio; Volatile Organic Compound Emission Control Measures for...Implementation Plan (SIP), several volatile organic compound (VOC) rules that were submitted...stationary sources, storage of volatile organic liquids, industrial cleaning...

2013-04-29

161

40 CFR 60.112b - Standard for volatile organic compounds (VOC).  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Standard for volatile organic compounds (VOC). 60.112b Section... Standards of Performance for Volatile Organic Liquid Storage Vessels (Including Petroleum... § 60.112b Standard for volatile organic compounds (VOC). (a) The...

2013-07-01

162

Identification and Quantification of Volatile Organic Compounds at a Dairy  

NASA Astrophysics Data System (ADS)

Livestock operations in the United States are an escalating environmental concern. The increasing density of livestock within a farm results in an increased emission of odorous gases, which have gained considerable attention by the public in recent years (National Research Council (NRC), 2002). Odorous compounds such as ammonia (NH3), volatile organic compounds (VOC's), and hydrogen sulfide (H2S) were reported to have a major effect on the quality of life of local residents living near livestock facilities (NRC, 2002). There has been little data collected related to identification and quantification of gaseous compounds collected from open stall dairy operations in the United States. The research to be presented identifies and quantifies VOCs produced from a dairy operation that contribute to odor and other air quality problems. Many different VOCs were identified in the air downwind of an open lactating cow stall area and near a waste lagoon at the Washington State University dairy using Gas Chromatography Mass Spectroscopy (GC-MS) analysis techniques. Identified compounds were very diverse and included many alcohols, aldehydes, amines, aromatics, esters, ethers, a fixed gas, halogenated hydrocarbons, hydrocarbons, ketones, other nitrogen containing compounds, sulfur containing compounds, and terpenes. The VOCs directly associated with cattle waste were dependent on ambient temperature, with the highest emissions produced during the summer months. Low to moderate wind speeds were ideal for VOC collection. Concentrations of quantified compounds were mostly below odor detection thresholds found in the literature, however the combined odor magnitude of the large number of compounds detected was most likely above any minimum detection threshold.

Filipy, J.; Mount, G.; Westberg, H.; Rumburg, B.

2003-12-01

163

Metamaterial resonator arrays for organic and inorganic compound sensing  

NASA Astrophysics Data System (ADS)

In this paper, an electromagnetic metamaterial resonator operating in the terahertz frequency range is presented. By arranging the resonator in a planar array, it is possible to use the structure as a sensing device for organic and inorganic compounds. The sensor is designed to detect the presence of a biological compound by permittivity or absorption measurements. The presence of the biological matter modifies the effective permittivity and, thus, the resonant frequency significantly varies. In addition, biological compounds typically exhibit absorption characteristics that depend on the corresponding molecular structure. Therefore, it is necessary to illuminate the material selectively. We show that by employing the "selective" properties of the metamaterial resonator proposed, it is possible to enhance the sensing performances. The proposed design is suitable to sense the presence of healthy and malignant tissues, with possible applications in food and medical diagnostics. The operation of the sensing device has been demonstrated through proper full-wave simulations.

La Spada, Luigi; Bilotti, Filiberto; Vegni, Lucio

2011-09-01

164

Nonlinear Laser Fluorescence Spectroscopy of Natural Organic Compounds  

NASA Astrophysics Data System (ADS)

Principles of nonlinear laser fluorescence spectroscopy of complicated organic compounds and of the method capable of determining photophysical parameters are considered in this chapter. Special attention is paid to the peculiarities of the method connected with specific photophysical processes in natural organic compounds, especially in proteins, and to the major role of intramolecular energy transfer and presence of localized donor-acceptor pairs (LDAP) of fluorophores within single macromolecules. These facts stimulated the development of models based on the collective states formalism describing fluorescent response of LDAP to pulsed laser excitation. Unique features of the method are illustrated by the example of proteins (proteins with intrinsic fluorescence (HSA, BSA) and fluorescent protein mRFP1) that can be used as fluorescent tags of intracellular processes while their photophysical parameters can be used as the information channel.

Fadeev, Victor V.; Shirshin, Evgeny A.

165

Transformations of organic compounds under the action of mechanical stress  

NASA Astrophysics Data System (ADS)

Transformations of organic compounds (monomeric and polymeric) under the action of mechanical stress are considered. Two types of processes occur under these conditions. The first type involves disordering and amorphisation of crystal structure and conformational transformations as a result of rupture of intermolecular bonds. The second type includes mechanochemical reactions activated by deformation of valence bonds and angles under mechanical stress, namely, the rupture of bonds, oxidation and hydrolysis. Data on the organic mechanochemical synthesis of new compounds or molecular complexes are systematised and generalised. It is demonstrated that mechanical treatment ensures mass transfer and the contact of reacting species in these reactions. Proteins are especially sensitive to mechanical stress and undergo denaturation; enzymes are inactivated. The bibliography includes 115 references.

Dubinskaya, Aleksandra M.

1999-08-01

166

Concentration stability of four volatile organic compounds in soil subsamples  

SciTech Connect

This study assesses the short-term (14- to 20-day) concentration stability of benzene, toluene, trans-1,2-dichloroethylene and trichloroethylene in soil matrices, in the absence of volatilization losses. Previously, holding time studies failed to eliminate volatilization as a variable, making them difficult to interpret. Here, vapor-fortified soil subsamples, sealed in glass ampoules for 16 days, experienced appreciable reductions in benzene, presumably attributable only to biodegradation. Treated soil subsamples, on the other hand, prepared without vapor losses for either aqueous extraction headspace or purge-and-trap analyses, showed appreciable reductions in toluene and lost all the benzene over a 14-day holding period at 4 deg C. These findings suggest that chemical preservatives are necessary to maintain volatile organic compound concentrations in soil when more than a couple of days pass between collection and analysis. Biodegradation, Soil samples, Holding time, Volatile-organic compounds.

Hewitt, A.D.

1994-04-01

167

Volatile organic compound (VOC) species data manual. Second edition  

SciTech Connect

This document contains tables of potential emissions of organic compounds for selected source categories. The species profile table format has been organized to be particularly useful in preparation of emission inventory inputs to photochemical modeling. Accompanying each VOC profile table is a brief narrative that describes process, emissions, controls, and basis of source report and data quantification. The chemical classifications include paraffin, olefin, aromatic, carbonyl (aldehydes and ketones), methane, non-reactive other than methane, and miscellaneous. Data confidence levels for each profile table have been assigned. Reports, published data, and names and titles of personal contacts are referenced for each source category.

Not Available

1980-07-01

168

Orientation dependent molecular friction on organic layer compound crystals  

NASA Astrophysics Data System (ADS)

High resolution friction force maps of the benzylammonium terminated crystalline surface of a layer compound are presented. The lateral force map acquired with an atomic force microscope, reveals a significant contrast between different molecular orientations yielding molecular rows which differ from their neighboring ones. The single crystals are formed by stacks of copper oxalate sheets sandwiched between stereoregular organic cations, resulting in highly organized surface structures. Single molecular defects are observed at small loads. The experimental results are compared with numerical calculations which indicate a transition from an unperturbed state at small loads to a distorted state at higher loads.

Fessler, Gregor; Zimmermann, Iwan; Glatzel, Thilo; Gnecco, Enrico; Steiner, Pascal; Roth, Raphael; Keene, Tony D.; Liu, Shi-Xia; Decurtins, Silvio; Meyer, Ernst

2011-02-01

169

Emission of volatile organic compounds (VOCs) from PVC floor coverings.  

PubMed

In this study 29 PVC floor coverings were tested for emission of vinyl chloride (VC) and other volatile organic compounds (VOCs). A study on the effect of higher temperature on emission of VOCs from newly manufactured PVC flooring was also carried out. The study was conducted in climatic chamber, according to Polish Standard PN-89/Z-04021. GC method was used for analyzing of the compounds emitted. VC was not emitted from any of the floorings tested. Other VOCs were emitted in different concentrations. The influence of temperature on emission was conducted at temperatures of 23 degrees C and 35 degrees C from 2 hrs up to 180 days after introduction of materials in the chamber. The increase of temperature caused increase of total volatile organic compounds (TVOC) emission during 24 hrs of experiment. Then the emission was comparable for both temperatures. After 9 days emission of identified and unidentified compounds (TVOC) showed a rapid decay and stayed on very low level during a few months. The study conducted showed that PVC floorings after 10 days of installation in the room should not be source of indoor air contamination. PMID:10431652

Wiglusz, R; Igielska, B; Sitko, E; Nikel, G; Jarnuszkiewicz, I

1998-01-01

170

Destruction of organic compounds in water using supported photocatalysts  

SciTech Connect

Photocatalytic destruction of organic compounds in water is investigated using tanning lamps and fixed-bed photoreactors. Platinized titanium dioxide (Pt-TiO{sub 2}) supported on silica gel is used as a photocatalyst. Complete mineralization of influent concentrations of 4.98 mg/L tetrachloroethylene and 2.35 mg/L p-dichlorobenzene requires a reactor residence time less than 1.3 minutes. While for influent concentrations of 3.58 mg/L 2-chlorobiphenyl, 2.50 mg/L methyl ethyl ketone and 0.49 mg/L carbon tetrachloride, complete mineralization requires reactor residence times of 1.6, 10.5, and 16.8 minutes, respectively. A reactor model is developed using Langmuir-Hinshelwood kinetics and the model parameters are determined using a reference compound, trichloroethylene. Based on the results of experiments with trichloroethylene, the model predicts the mineralization of the aforementioned compounds from ultraviolet (UV) irradiance, influent concentration, hydroxyl radical rate constants, and the known physical properties of the compounds. The model is also able to predict organic destruction using solar insolation (which has a different spectral distribution from the tanning lamps) based on the UV absorption characteristics of titanium dioxide.

Zhang, Y.; Crittenden, J.C.; Hand, D.W.; Perram, D.L. [Michigan Technological Univ., Houghton, MI (United States). Dept. of Civil and Environmental Engineering

1996-05-01

171

Volatile organic compound emissions: an inventory for Western Europe  

SciTech Connect

The report gives details of an inventory compiled by CONCAWE and covering man-made non-methane volatile organic compound (VOC) emissions in Western Europe. The survey shows that the major man-made sources are road transport and solvents, each contributing around 40%. Total oil industry operations account for around 8%, with refining operations contribution about 2%. The major oil industry contribution comes from the distribution of gasoline, including vehicle refuelling (5%).

Edwards, A.H.; Campobasso, A.; Camps, R.; Cremer, G.; Long, M.D.

1986-01-01

172

Compositions of volatile organic compounds and methods of use thereof  

US Patent & Trademark Office Database

The present invention provides compositions and methods for treating, inhibiting or preventing the developing of a plant pathogenic disease. The compositions comprise volatile organic compounds effective to inhibit the growth of, or kill pathogenic microbes, including Ganoderma boninense. Invention compositions are especially useful in preventing and treating basal stem rot in the oil palm, and can be applied in the vicinity of the plant or used to sterilize the plant growth medium prior to or concurrent with plant growth therein.

2013-04-23

173

Determination of total volatile organic compound emissions from furniture polishes  

Microsoft Academic Search

In this study, an environmental test chamber with controlled temperature, relative humidity, and airflow rate was developed\\u000a to evaluate emissions of total volatile organic compounds (TVOCs) from three different kinds of furniture polish. The time\\u000a dependence of TVOC concentrations produced from the emissions of furniture polish products in the chamber was tested. TVOC\\u000a emissions from each furniture polish were compared.

Hai Guo; Frank Murray

2001-01-01

174

Influence of sorbate structure on nonequilibrium sorption of organic compounds  

Microsoft Academic Search

The authors investigate the relationship between sorbate structure and nonequilibrium sorption. The rate-limited sorption of compounds representing eight classes of organic chemicals, including chlorinated benzenes, unsubstituted and alkyl-substituted aromatics, chlorinated ethenes and ethanes, chlorinated phenols, nitrogen heterocycles, s-triazines, substituted amides, and substituted ureas, was examined by use of a single sorbent (sandy aquifer material) and the miscible displacement technique. The

Mark L. Brusseau; P. Suresh C. Rao

1991-01-01

175

Water Pollution: Organic Compounds in the Charles River, Boston  

Microsoft Academic Search

The major lipophilic organic compounds present in water collected during November and December 1971 from the Charles River Basin (Boston) are as follows: normal alkanes (C15 to C31), alkyl naphthalenes, alkyl anthracenes or phenanthrenes, pyrene, fluoranthene, dibutyl phthalate, and di(2-ethylhexyl) phthalate. The concentration of the naphthalenes (determined by liquid chromatography) correlates with the effective storm-water runoff content of the river.

Ronald A. Hites; K. Biemann

1972-01-01

176

Relationships between melting point and boiling point of organic compounds  

SciTech Connect

Relationships between melting point and boiling point are shown to be dependent upon the molecular symmetry number and a modified count of the total number of atoms in the molecule. Using the above relationships, the boiling and melting points of nearly 1,000 non-hydrogen-bonding organic compounds have been correlated. The correlations for boiling point and melting point have root mean square errors of 28 and 36 C, respectively.

Yalkowsky, S.H.; Krzyzaniak, J.F.; Myrdal, P.B. (Univ. of Arizona, Tucson, AZ (United States). College of Pharmacy)

1994-07-01

177

Gas-phase degradation of organic compounds in the troposphere  

Microsoft Academic Search

The present status of knowledge of the gas-phase reactions of selected classes of volatile non-methane organic compounds (NMOCs) (alkanes, alkenes, aromatic hydrocarbons, oxygen-containing NMOCs and nitrogen-containing NMOCs) and their degradation products in the troposphere is briefly discussed. In the troposphere, NMOCs can undergo photolysis, reaction with the hydroxyl (OH) radical during daylight hours, reaction with the nitrate (NO3) radical (primarily

Roger Atkinson

1998-01-01

178

Identification of nonmethane organic compound emissions from grassland vegetation  

Microsoft Academic Search

Emissions of nonmethane organic compounds (NMOCs) from grassland vegetation were collected in Summa® passivated stainless-steel canisters with a static enclosure technique and were analyzed by high-resolution gas chromatography with flame ionization and ion trap mass spectrometric detectors. Approximately 40NMOCs with 6–10 carbon atoms were observed in samples analyzed by high-resolution gas chromatography with the flame ionization detector. Nineteen NMOCs in

Yoshiko Fukui; Paul V. Doskey

2000-01-01

179

The synthesis of organic and inorganic compounds in evolved stars  

Microsoft Academic Search

Recent isotopic analysis of meteorites and interplanetary dust has identified solid-state materials of pre-solar origin. We can now trace the origin of these inorganic grains to the circumstellar envelopes of evolved stars. Moreover, organic (aromatic and aliphatic) compounds have been detected in proto-planetary nebulae and planetary nebulae, which are the descendants of carbon stars. This implies that molecular synthesis is

Sun Kwok

2004-01-01

180

Oxidation of organic compounds in a microstructured catalytic reactor  

Microsoft Academic Search

A microstructured catalytic reactor for the oxidation of organic compounds has been fabricated from aluminum alloy AlMgSiCu1 (6082 series, Al51st). The catalyst section was assembled of 63 microstructured plates with catalytic coating. In each plate of 416?m thickness, 45 semi-cylindrical microchannels of 208?m in radius with a distance in between of 150?m were electrodischarge machined. A porous alumina layer of

I. Z. Ismagilov; E. M. Michurin; O. B. Sukhova; L. T. Tsykoza; E. V. Matus; M. A. Kerzhentsev; Z. R. Ismagilov; A. N. Zagoruiko; E. V. Rebrov; J. C. Schouten

2008-01-01

181

DFT derived solvation models for organic compounds in alkane solvents  

NASA Astrophysics Data System (ADS)

From a density functional theory (DFT) analysis of solvation and the different components which comprise the free energy of solvation we propose quantitative structure property relationship (QSPR) models to predict free energy of solvation, ?GS0, of organic compounds in seven alkane solvents (n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, and n-hexadecane). The data contains 151 structurally different compounds containing diverse organic functions: unbranched and branched alkanes, cycloalkanes, aromatics, alcohols, aldehydes, ketones, esters, ethers, amines, nitriles, pyridines, fluorinated hydrocarbons, thiols, sulfides, carboxylic acids and nitro hydrocarbons; covering a ?GS0 range from about -50 to 0 kJ/mol. The models for the seven n-alkane solvents contain the same two molecular descriptors, one DFT descriptor (softness) and one geometric (molecular surface area). This fact suggests that the physical mechanisms behind the solvation of organic compounds in n-alkane solvents are of the same nature, as expected from the similar physical and chemical properties of alkanes. The models proposed have the merit of predicting free energy of solvation in alkane solvents with fewer descriptors than other QSPR models reported in the literature having similar statistics, allowing in this way a well-defined physical interpretation. The two descriptors have definite physical meaning corresponding to the different components which comprise free energy of solvation. Thus, the models proposed reach the desired compromise among simpleness, physical interpretation and computation time.

Delgado, Eduardo J.; Alderete, Joel B.; Jaña, Gonzalo A.

2006-06-01

182

Contribution of organosulfur compounds to organic aerosol mass.  

PubMed

Organosulfates have been proposed as products of secondary organic aerosol formation. While organosulfates have been identified in ambient aerosol samples, a question remains as to the magnitude of their contribution to particulate organic mass. At the same time, discrepancies have been observed between total particulate sulfur measured by X-ray fluorescence (XRF) spectroscopy and sulfur present as inorganic sulfate measured by ion chromatography (IC) in fine particulate matter. These differences could be attributed to measurement bias and/or the contribution of other sulfur compounds, including organosulfates. Using the National Park Service IMPROVE PM(2.5) database, we examined the disparity between the sulfur and sulfate measurements at 12 sites across the United States to provide upper-bound estimates for the annual average contributions of organosulfates to organic mass. The data set consists of over 150000 measurements. The 12 sites include Brigantine, NJ, Cape Cod, MA, Washington, DC, Chassahowitzka, FL, Great Smoky Mountains National Park, NC, Okefenokee, GA, Bondville, IL, Mingo, MO, Phoenix, AZ, San Gabriel, CA, Crater Lake National Park, OR, and Spokane, WA. These sites are representative of the different regions of the country: Northeast, Southeast, Midwest, Southwest and Northwest. We estimate that organosulfur compounds could comprise as much as 5-10% of the organic mass at these sites. The contribution varies by season and location and appears to be higher during warm months when photochemical oxidation chemistry is most active. PMID:22731120

Tolocka, Michael P; Turpin, Barbara

2012-07-16

183

Interaction of Saharan dust particles with semivolatile organic compounds  

NASA Astrophysics Data System (ADS)

Mineral dust particles can be transported over long distances. During transport, mineral dust particles can interact with semi-volatile organic compounds present in the atmosphere, either as local pollution or as photochemical oxidation products of volatile species. Here we report on the interaction of organic species with mineral dust particles from the Sahara over an urban region. The dust samples were collected in Israel during spring 2001, covering several dust storm events. In an integrated, multi-technique study, using Scanning Electron Microscope equipped with energy dispersion system (SEM-EDS) and bulk aerosol analysis (gas chromatography/ mass spectrometry and ion chromatography methods), the organic and inorganic content of mineral dust particles collected during dust storms were studied. Particles were collected on 8-stages impactors for size segregated analysis, by high volume samplers for ion chromatography and GC analysis, on 47 mm PTFE filters for ion chromatography, and on silicon substrates for SEM-EDS analysis. Many mixed inorganic and organic particles were identified by individual particle SEM-EDS analysis of the collected particles. We will present the findings from the SEM analysis exemplifying the existence of the mixed particles. Using direct sample introduction followed by thermal desorption GC/MS and ion chromatography analysis, tracers for urban air pollution, of photochemical degradation products of biogenic volatile organic compounds as well as tracers of biomass burning were probed and quantified. The effect of the dust storms on the size distribution of semi-volatile organics will be discussed. Differences in the redistribution behavior between local pollution, photochemical degradation products and tracers of biomass burning will be highlighted.

Rudich, Y.; Falkovich, A. H.

2001-12-01

184

Decomposition of Organic Compounds at the Martian Surface  

NASA Astrophysics Data System (ADS)

The 1976 Viking Landers were unable to detect organic compounds indigenous to Mars or that which has been delivered to the surface through meteoritic accumulations. A number of mechanisms for destroying organic material have been proposed to explain the in-situ results. These include destruction by ultraviolet radiation as well as through reactions with active oxygen species, products of atmospheric photochemistry, and reactive surfaces produced by mineral fracturing. The results of chemical analyses preformed by the Alpha Particle X- ray Spectrometers (APXS) onboard the Mars Exploration Rovers (MER) suggest that yet another mechanism could have been active. The APXS data show a constant sulfur to chlorine ratio of approximately 3.7:1 for most samples of unconsolidated regolith. Due to the absence of an obvious cation, this observed ratio is not likely to be a product of mixing with distinct sulfate and chloride phases, but rather in the form of a rind on mineral grain surfaces. The initial source of the S and Cl is believed to be volcanic outgassing in the form of HCl, SO2, and H2SO4. Reactions with martian surface materials produce localized sulfates and chlorides. Interactions with acidic volatiles, however, are also extremely effective in decomposing organic compounds. All of the samples analyzed by the Viking Landers exhibited SO3 levels of approximately 6 weight percent or greater and S:Cl ratios consistent with the MER results, suggesting that extensive exposure to products of volcanic emissions could be the reason that martian organics were not detected. Future attempts to evaluate the carbon inventory of the martian surface environment will include instrumentation more sensitive than delivered by Viking, but the greatest chance of discovering carbon compounds on Mars may involve samples which have not been exposed to volcanic gases.

Yen, A. S.; Clark, B. C.; Hurowitz, J. A.; Athena Science Team

2006-12-01

185

Multiple microbial activities for volatile organic compounds reduction by biofiltration.  

PubMed

In the northeast of Italy, high volatile organic carbon (VOC) emissions originate from small-medium companies producing furniture. In these conditions it is difficult to propose a single, efficient, and economic system to reduce pollution. Among the various choices, the biofiltration method could be a good solution, because microbial populations possess multiple VOC degradation potentials used to oxidize these compounds to CO2. Starting from the air emissions of a typical industrial wood-painting plant, a series of experiments studied in vitro microbial degradation of each individual VOC. Isolated strains were then added to a laboratory-scale biofiltration apparatus filled with an organic matrix, and the different VOC behavior demonstrated the potential of single and/or synergic microbial removal actions. When a single substrate was fed, the removal efficiency of a Pseudomonas aeruginosa inoculated reactor was 1.1, 1.17, and 0.33 g m(-3) hr(-1), respectively, for xylene, toluene, and ethoxy propyl acetate. A VOC mixture composed of butyl acetate, ethyl acetate, diacetin alcohol, ethoxy propanol acetate, methyl ethyl ketone, methyl isobutyl ketone, toluene, and xylene was then fed into a 2-m(3) reactor treating 100 m3 hr(-1) of contaminated air. The reactor was filled with the same mixture of organic matrix, enriched with all of the isolated strains together. During reactor study, different VOC loading rates were used, and the behavior was evaluated continuously. After a short acclimation period, the removal efficiency was > 65% at VOC load of 150-200 g m(-3) hr(-1). Quantification of removal efficiencies and VOC speciation confirmed the relationship among removal efficiencies, compound biodegradability, and the dynamic transport of each mixture component within the organic matrix. Samples of the fixed bed were withdrawn at different intervals and the heterogeneous microbial community evaluated for both total and differential compound counts. PMID:16878585

Civilini, Marcello

2006-07-01

186

Determination of organic nitro compounds using HPLC-UV-PAED  

NASA Astrophysics Data System (ADS)

High-performance liquid chromatography with ultra violet and photo-assisted electrochemical detection (HPLC-UV-PAED) has been applied to the sensitive and selective determination of organic nitro compounds. The system was first developed for the determination of nitro explosives, and PAED has shown superior sensitivity over UV detection for these compounds (i.e., <1 part-per-trillion for HMX). The system also shows enhanced selectivity over the traditional UV method in that two detectors can be used for improved analyte identification. Also, having two detectors permits chemometric resolution of overlapping peaks, and this is not addressed in the UV method. Because this method is applicable to a wide range of nitro explosives, it was predicted that PAED would show the same sensitivity and selectivity toward other types of nitro compounds. Since its development, the system's use has been expanded to include the determination of nitro-containing pharmaceuticals and glycosylated nitro compounds in biological matrices. Model compounds were chosen, specifically nitroglycerin and related compounds and nitrophenyl-glucoside, to represent these classes. PAED showed superior detection limits over low wavelength UV detection for nitroglycerin (PAED = 0.3ppb, UV at 220nm = 48ppb), demonstrating PAED"s applicability to determining nitro-pharmaceuticals. Conversely, UV detection at 220nm proved to be more sensitive than PAED for nitrophenyl-glucoside (UV at 220 = 0.6ppb, PAED = 3.6ppb). However, when nitrophenyl-glucoside was spiked into urine, PAED determination resulted in 99+0.3% recovery, while UV at 220nm resulted in 116+0.2% recovery, suggesting that UV determination may suffer from matrix interference.

Marple, Ronita L.; LaCourse, William R.

2004-10-01

187

Potential risks from exposure to organic compounds in indoor air  

SciTech Connect

This report is a preliminary assessment of the potential risks of cancer, reproductive effects, and miscellaneous toxic effects from exposures to individual organic compounds which have been detected in indoor air. Published data in indoor concentrations of organic compound were compiled. The principal basis for estimates of cancer were data from animal studies. Potency factors used in the risk calculations were estimated by EPA and by other authors. EPA potency factors were estimated by ''unit risk,'' the lifetime risk to humans from daily inhalation of a unit concentrations (e.g., 1 ..mu..g/m/sup 3/). A TD50 is defined as the daily dose rate that would induce tumor in half the test animals that would have remained tumor-free at zero dose. TD50s were converted to ''human equivalent inhalation'' TD50s to estimate cancer risks for median and maximum concentrations. Maximum likelihood (MLE) risks and 95% upper confidence limit risks were also calculated. For reproductive effects, the ''lowest effective dose'' (LED) in animals was converted to a ''human equivalent inhalation'' dose and compared to the maximum and the mean or median indoor concentrations reported for that compound. Based on the limited data available, it is concluded that risks of adverse health effects do not appear to be large in the great majority of homes. In some fraction of homes, however, a significant health risk may exist. 60 refs., 5 figs., 13 tabs.

McCann, J.; Horn, L.; Girman, J.; Nero, A.V.

1988-05-01

188

Volatile organic compound losses from sewage sludge-amended soils  

SciTech Connect

Volatile organic compounds (VOCs) applied to soil in sludge have been assumed to disappear quickly and completely. The VOC behavior in sludge-amended soils has been studied previously only in laboratory systems where the sludged soil has been spiked with compounds of interest. Behavior in these systems may not necessarily represent compound behavior in field soils to which contaminated sludge is added. A series of laboratory microcosm experiments were designed therefore to investigate the behavior of toluene, ethyl benzene, o-, m-, and p-xylene applied to soil in contaminated sludge, and factors influencing loss processes. The VOC loss from sludge-amended soil was well described by a simple one step pseudo-first-order model but in certain soils was better described by a two step first-order model. Volatilization was the predominant loss process. Rates of loss depended on sludge application rate, method of sludge application, soil properties, and on compound characteristics. Experiments indicated that spiking sludge-amended soils gave a reasonable indication of VOC loss rates from systems amended with contaminated sludge at least over a period of 23 d. The majority of VOCs applied to soils in sludge volatilizes quickly to the atmosphere over a few to 10s of days with a small fraction lost more slowly. Potential for VOC crop uptake, livestock ingestion, and contamination of ground water is low under routine, managed applications of sewage sludge to agricultural land.

Wilson, S.C.; Jones, K.C.

1999-08-01

189

Microbial degradation of water-insoluble organic compounds  

SciTech Connect

The effect of solubilization on biodegradation of water-insoluble organic compounds was investigated. The effect of particle size on solubilization and degradation of 4-chlorobiphenyl (4-CB) and naphthalene by a microbial mixture was determined. The concentration of soluble compound was determined using gas-liquid chromatography. The rates of solubilization were inversely related to particle size for both compounds. The rates of mineralization of /sup 14/C-labeled palmitic acid, octadecane, di(2-ethylhexyl)phthalate (DEHP), and Sevin (1-naphthyl N-methylcarbamate) by microbial mixtures were determined by trapping the /sup 14/CO/sub 2/ formed, and those rates were compared to solubilization rates determined by periodically filtering sterile MS amended with one of the compounds. Mineralization and colonization of the surface of 10 ..mu..g palmitic acid per 10 ml MS by Pseudomonas pseudoflava was determined by trapping /sup 14/CO/sub 2/ and epifluorescence microscopy. Mineralization began before colonization and was initially exponential, but the rate then declined. The rate of mineralization at the end of the exponential phase approximated the rate of solubilization. The surface was completely covered about the time mineralization stopped. Unbound cells grew exponentially before colonization was detected; however, colonization of the surface was complete after the number of free cells stopped increasing. The data suggest that soluble palmitic acid is utilized before the insoluble phase but colonization is important in the mineralization of palmitic acid when solubilization becomes rate limiting.

Thomas, J.M.

1985-01-01

190

Volatile organic compounds from a Tuber melanosporum fermentation system.  

PubMed

A total of 59 volatile organic compounds (VOCs) were identified from Tuber melanosporum fermentation: 53 from its fermented mycelia and 32 from the fermentation broth. Alcohol-derived compounds were predominant in both the fermentation mycelia and the broth, although long chain fatty acids and isoprenoids were, for the first time, also found in the mycelia. The intense wine bouquet properties of the broth arose from several specific flavor substances, including sulfur compounds, pyrazines, furans and jasmones. Comparing the VOCs identified in this work with those previously reported, our results are more similar to the composition of the Tuber fruiting-body than previous Tuber fermentations. The composition and accumulation of flavor volatiles (e.g., pyrazines, sulfur compounds, and esters) and major constituents (e.g., 3-methyl-1-butanol and 2-phenylethanol) in this fermentation were significantly influenced by the sucrose concentration in the medium. The obtained information could therefore be useful in applications to convert the flavors of truffle mycelia similar to those of the fruiting-body by optimising the fermentation process. PMID:22980851

Li, Yuan-Yuan; Wang, Guan; Li, Hong-Mei; Zhong, Jian-Jiang; Tang, Ya-Jie

2012-07-14

191

Removal of volatile organic compounds from paper coatings  

NASA Astrophysics Data System (ADS)

From the chemical point of view paper coatings are mainly polymer dispersions. Polymer dispersions are constituted in multitude fields, for example as dispersion coatings or adhesives. As far as no additional treatment is done, polymer materials as well as polymer agents contain non polymer, volatile organic components that may arise from: (1) incomplete polymerization of the applied monomers, (2) primary materials containing non polymerizable components, (3) undesirable side reactions during the synthesis. Requirements for the removal of volatile substances from polymer dispersion are given by several reasons: (1) low molecular substances deteriorate the product characteristics (viscosity, thermal stability and others), (2) in order to comply with legislative standards, volatile organic compounds have to be removed from dispersions, especially when applied to large surfaces (e.g. in surface refining in paper and leather industries as well as on coating). The removal of volatile organic compounds (deodorization) can be realized in continuous or discontinuous processes. In contrast to highly developed process technology, the process itself is not well understood, especially mass transport phenomena between the gas phase and the aqueous polymer dispersion are insufficiently and controversially discussed in the literature. Two processes, their advantages and disadvantages and the description by mathematical- mechanistic models are presented in this paper.

Meier, Dirk; Warnecke, Hans-Joachim; Pruess, Jan

1997-08-01

192

QSPR Modeling of Bioconcentration Factors of Nonionic Organic Compounds  

PubMed Central

The terms bioaccumulation and bioconcentration refer to the uptake and build-up of chemicals that can occur in living organisms. Experimental measurement of bioconcentration is time-consuming and expensive, and is not feasible for a large number of chemicals of potential regulatory concern. A highly effective tool depending on a quantitative structure-property relationship (QSPR) can be utilized to describe the tendency of chemical concentration organisms represented by, the important ecotoxicological parameter, the logarithm of Bio Concentration Factor (log BCF) with molecular descriptors for a large set of non-ionic organic compounds. QSPR models were developed using multiple linear regression, partial least squares and neural networks analyses. Linear and non-linear QSPR models to predict log BCF of the compounds developed for the relevant descriptors. The results obtained offer good regression models having good prediction ability. The descriptors used in these models depend on the volume, connectivity, molar refractivity, surface tension and the presence of atoms accepting H-bonds.

Deeb, Omar; Khadikar, Padmakar V.; Goodarzi, Mohammad

2010-01-01

193

Heterogeneous reactions of volatile organic compounds in the atmosphere  

NASA Astrophysics Data System (ADS)

Volatile organic compounds (VOCs) are of central importance in the atmosphere because of their close relation to air quality and climate change. As a significant sink for VOCs, the fate of VOCs via heterogeneous reactions may explain the big gap between field and model studies. These reactions play as yet unclear but potentially crucial role in atmospheric processes. In order to better evaluate this reaction pathway, we present the first specific review for the progress of heterogeneous reaction studies on VOCs, including carbonyl compounds, organic acids, alcohols, and so on. Our review focuses on the processes for heterogeneous reactions of VOCs under varying experimental conditions, as well as their implications for trace gas and HOx budget, secondary organic aerosol (SOA) formation, physicochemical properties of aerosols, and human health. Finally, we propose the future direction for laboratory studies of heterogeneous chemistry of VOCs that should be carried out under more atmospherically relevant conditions, with a special emphasis on the effects of relative humidity and illumination, the multicomponent reaction systems, and reactivity of aged and authentic particles. In particular, more reliable uptake coefficients, based on the abundant elaborate laboratory studies, appropriate calibration, and logical choice criterion, are urgently required in atmospheric models.

Shen, Xiaoli; Zhao, Yue; Chen, Zhongming; Huang, Dao

2013-04-01

194

Identification of volatile organic compounds polluting the atmosphere  

SciTech Connect

For an exact evaluation of the state of man`s environment and to adopt preventive measures to reduce the effect of human influences on it, it is necessary to know the of pollutants entering the atmosphere from various industrial sources. Chromatography methods of analysis are used in most of the analytical methods proposed for the solution of this problem. They enable the identification of the individual substances or a number of compounds within a given class. The chromato-mass spectrometric (CMS) method using high performance capillary separation overcomes this limitation and makes it possible to identify a considerably larger number of organic pollutants of quite different types. At present a standard method is used in the USA for the determination of critical pollutants in the atmosphere of urban areas, which was developed by the Environmental Protection Agency. There are similar methods in operation in other countries.Investigations in this field are limited in character in the Soviet Union. The present work outlines the results of investigations carried out with respect to sampling and structural identification of volatile organic compounds in the atmosphere of urban areas. The methods are based on the principle of sorption of the organic pounds on a solid carrier with subsequent thermal desorption and transfer of the solid components to the chromatograph of a CMS system. Examples of the use of the adsorption concentration on Tenax type sorbents have been described in the literature. 6 refs., 3 figs., 3 tabs.

Zamureenko, V.A.; Matveev, A.K.; Shik, N.V. [A.N. Severtsov Inst. of Evolutionary Morphology and Animal Ecology, Moscow (Russian Federation)] [and others

1992-03-10

195

Odors and volatile organic compounds released from ventilation filters  

NASA Astrophysics Data System (ADS)

Used supply air filters were studied by sensory and chemical methods. In addition, filter dust was examined by thermodesorption/cold trap (TCT) and headspace (HS) devices connected to a GC-MS. The prefilter was the main odor source in the ventilation unit, but when humidifier was turned on odor was released mainly from the fine filter. However, the effect of the relative humidity (RH) was only temporary. At the same time, there was an increase in the concentration of aldehydes after the filters. Aldehydes, carboxylic acids, and nitrogen-containing organic compounds were the main emission products in the thermodesorption analyses of the filter dust. Many of these compounds have low odor threshold values and, therefore, contribute to the odor released from the filters. Especially, the role of aldehydes seems to be important in the odor formation.

Hyttinen, Marko; Pasanen, Pertti; Björkroth, Marko; Kalliokoski, Pentti

196

Seeking organic compounds on Mars : in situ analysis of organic compounds by Gas Chromatography-Mass Spectrometry on MOMA experiment  

NASA Astrophysics Data System (ADS)

The search for signs of past or present life is one of the primary goals of future Mars exploratory missions. The Mars Organic Molecule Analyzer (MOMA) experiment of the ExoMars mission (set to launch 2016-2018) is a joint venture by the European Space Agency and NASA to develop a sensitive detector for organics on Mars. MOMA will be one of the main analytical instruments aboard the ExoMars Rover aimed at characterizing possible “signs-of-life molecules” in the Martian environment such as amino acids, carboxylic acids, nucleobases or polycyclic aromatic hydrocarbons (PAHs). With the aim to separate and detect organic compounds from Martian soil, the French MOMA team has built a gas chromatograph able to work in standalone mode by using a TCD detector. The gas chromatograph can also be coupled with an ion trap mass spectrometer developed by the US MOMA team. Moreover, a GC-MS compatible sample processing system (SPS) allowing the extraction and the chemical transformation of the organic compounds from the soil, that fits within space flight conditions, has also been developed. The sample processing is performed in an oven, dedicated to the MOMA experiment containing the solid sample (50-100mg). The internal temperature of oven can be ranged from 20 to 1000 °C which allows for pyrolysis, thermochemolysis or derivatization. The organic extraction step is achieved by using thermodesorption in the range of 100 to 300°C for 0.5 to 5 min. Then, the chemical derivatization and/or thermochemolysis of the extracted compounds is performed directly on the soil with a mixture of MTBSTFA-DMF, TMAH or DMF-DMA solution when enantiomeric separation is required. By decreasing the polarity of the target molecules, this step allows for their volatilization at a temperature below 250°C without any chemical degradation. Once derivatized, the volatile target molecules are trapped in a cold chemical trap and promptly desorbed into the gas chromatograph coupled to the mass spectrometer. Preliminary tests, performed on several analogue soils such as Atacama soil, with the MOMA SPS-GC/MS experiment demonstrated the capability to detect organic compounds such as amino and carboxylic acids with sensitivities below the ppm level.

Buch, A.; Freissinet, C.; Sternberg, R.; Pinnick, V.; Szopa, C.; Coll, P. J.; Rodier, C.; Garnier, C.; Steininger, H.; Moma Team

2010-12-01

197

Hazardous organic compounds in groundwater near Tehran automobile industry.  

PubMed

Potential of groundwater contamination by trichloroethylene (TCE) and other volatile organic compounds VOCs near car industry was conducted in this study. TCE, PCE, toluene, xylene, dichloromethane, cyclohexane, n-hexane and n-pentane were detected in all groundwaters. Mean TCE levels in groundwater ranged from 124.37 to 1,035.9 ?g L?¹ with maximum level of 1,345.7 ?g L?¹. Due to the data obtained from conventional wastewater treatment in car factory the TCE removal efficiency was only 24 percent which necessitates the TCE removal by advanced treatment processes before the use of well water. PMID:21069286

Dobaradaran, Sina; Mahvi, Amir Hossein; Nabizadeh, Ramin; Mesdaghinia, Alireza; Naddafi, Kazem; Yunesian, Masoud; Rastkari, Noushin; Nazmara, Shahrokh

2010-11-11

198

Process for removing an organic compound from water  

DOEpatents

A process for removing organic compounds from water is disclosed. The process involves gas stripping followed by membrane separation treatment of the stripping gas. The stripping step can be carried out using one or multiple gas strippers and using air or any other gas as stripping gas. The membrane separation step can be carried out using a single-stage membrane unit or a multistage unit. Apparatus for carrying out the process is also disclosed. The process is particularly suited for treatment of contaminated groundwater or industrial wastewater.

Baker, Richard W. (Palo Alto, CA); Kaschemekat, Jurgen (Palo Alto, CA); Wijmans, Johannes G. (Menlo Park, CA); Kamaruddin, Henky D. (San Francisco, CA)

1993-12-28

199

Volatile organic compounds in storm water from a parking lot  

USGS Publications Warehouse

A mass balance approach was used to determine the most important nonpoint source of volatile organic compounds (VOCs) in storm water from an asphalt parking lot without obvious point sources (e.g., gasoline stations). The parking lot surface and atmosphere are important nonpoint sources of VOCs, with each being important for different VOCs. The atmosphere is an important source of soluble, oxygenated VOCs (e.g., acetone), and the parking lot surface is an important source for the more hydrophobic VOCs (e.g., benzene). VOCs on the parking lot surface appear to be concentrated in oil and grease and organic material in urban particles (e.g., vehicle soot). Except in the case of spills, asphalt does not appear to be an important source of VOCs. The uptake isotherm of gaseous methyl tert-butyl ether on urban particles indicates a mechanism for dry deposition of VOCs from the atmosphere. This study demonstrated that a mass balance approach is a useful means of understanding non-point-source pollution, even for compounds such as VOCs, which are difficult to sample.A mass balance approach was used to determine the most important nonpoint source of volatile organic compounds (VOCs) in storm water from an asphalt parking lot without obvious point sources (e.g., gasoline stations). The parking lot surface and atmosphere are important nonpoint sources of VOCs, with each being important for different VOCs. The atmosphere is an important source of soluble, oxygenated VOCs (e.g., acetone), and the parking lot surface is an important source for the more hydrophobic VOCs (e.g., benzene). VOCs on the parking lot surface appear to be concentrated in oil and grease and organic material in urban particles (e.g., vehicle soot). Except in the case of spills, asphalt does not appear to be an important source of VOCs. The uptake isotherm of gaseous methyl tert-butyl ether on urban particles indicates a mechanism for dry deposition of VOCs from the atmosphere. This study demonstrated that a mass balance approach is a useful means of understanding non-point-source pollution, even for compounds such as VOCs, which are difficult to sample.

Lopes, T. J.; Fallon, J. D.; Rutherford, D. W.; Hiatt, M. H.

2000-01-01

200

Adsorption of volatile organic compounds in porous metal–organic frameworks functionalized by polyoxometalates  

Microsoft Academic Search

The functionalization of porous metal–organic frameworks (Cu3(BTC)2) was achieved by incorporating Keggin-type polyoxometalates (POMs), and further optimized via alkali metal ion-exchange. In addition to thermal gravimetric analysis, IR, single-crystal X-ray diffraction, and powder X-ray diffraction, the adsorption properties were characterized by N2 and volatile organic compounds (VOCs) adsorption measurements, including short-chain alcohols (C<4), cyclohexane, benzene, and toluene. The adsorption enthalpies

Feng-Ji Ma; Shu-Xia Liu; Da-Dong Liang; Guo-Jian Ren; Feng Wei; Ya-Guang Chen; Zhong-Min Su

2011-01-01

201

Antioxidant combinations of molybdenum complexes and organic sulfur compounds for lubricating oils  

SciTech Connect

An antioxidant additive combination for lubricating oils is prepared by combining (a) a sulfur containing molybdenum compound prepared by reacting an ammonium tetrathiomolybdate, and a basic nitrogen compound, with (b) an organic sulfur compound.

deVries, L.; King, J.M.

1983-09-06

202

Organochlorine Pesticide Compounds in Organisms from the Bay of Bengal  

NASA Astrophysics Data System (ADS)

Zooplankton and bottom-feeding fish (four species) from the coastal Bay of Bengal were analysed for residues of DDT, DDD, DDE and aldrin. Concentrations of t-DDT (DDT+DDD+DDE) ranging from 1·31 to 115·90 ng g -1 wet weight in different fish tissues and 4·00 to 1587·76 ng g -1 wet weight in zooplankton were found. Aldrin levels were of the order of 0·32-4·23 ng g -1 in the fish tissues and 'not detected' to 0·78 ng g -1 in zooplankton. The concentration levels are discussed in relation to the distribution of the compounds in different fish tissues, differences in the proportion of DDT and its metabolites DDE and DDD in the various organisms and the possible influence of suspended particulate matter on the availability of DDT residues to organisms in the water column.

Shailaja, M. S.; Singbal, S. Y. S.

1994-09-01

203

Laboratory Studies of Organic Compounds With Reflectance Spectroscopy  

NASA Astrophysics Data System (ADS)

In order to properly interpret reflectance spectra of any solar system surface from the earth to the Oort cloud, laboratory spectra of candidate materials for comparative analysis are needed. Although the common cosmochemical species (H2O, CO2, CO, NH3, and CH4) are well represented in the spectroscopic literature, comparatively little reflectance work has been done on organics from room to cryogenic temperatures at visible to near infrared wavelengths. Reflectance spectra not only enhance weak or unseen transmission features, they are also more analogous to spectra obtained by spacecraft that are imaging such bodies as giant planet moons, kuiper belt objects, centaurs, comets and asteroids, as well as remote sensing of the earth. The USGS Spectroscopy Laboratory is measuring reflectance spectra of organic compounds from room to cryogenic temperatures over the spectral range of 0.35 to 15.5 microns. This region encompasses the fundamental absorptions and many overtones and combinations of C, H, O, and N molecular bonds. Because most organic compounds belong to families whose members have similar structure and composition, individual species identification within a narrow wavelength range may be ambiguous. By measuring spectral reflectance of the pure laboratory samples from the visible through the near and mid-infrared, absorption bands unique to each can be observed, cataloged, and compared to planetary reflectance data. We present here spectra of organic compounds belonging to five families: the alkanes, alkenes, alkynes, aromatics, and cyanides. Common to all of these are the deep C-H stretch fundamental absorptions, which shift shortward from 3.35+ microns in alkanes to 3.25+ microns in aromatics, to 3.2+ microns in alkenes, and down to 3.0+ microns in alkynes. Mid-IR absorptions due to C-H bending deformations at 6.8+ and 7.2+ microns are also identified. In the near infrared these stretching and bending fundamentals yield a diagnostic set of combination absorptions at approximately 2.3 microns, as well as the first C-H stretching overtones at 1.6 to 1.7 microns, and even the second stretching overtones at 1.2+ microns. Additionally, the spectral properties of these organic materials have applications to remote sensing of terrestrial environments, including hazardous waste and disaster site characterization.

Curchin, J. M.; Clark, R. N.; Hoefen, T. M.

2007-12-01

204

75 FR 82363 - Approval and Promulgation of Implementation Plans; Ohio; Volatile Organic Compound Emission...  

Federal Register 2010, 2011, 2012, 2013

...Implementation Plans; Ohio; Volatile Organic Compound Emission Control Measures...and letterpress printing volatile organic compound (VOC) rule for approval into...with potential VOC ink oil emissions from the...

2010-12-30

205

Biogeochemical processes governing exposure and uptake of organic pollutant compounds in aquatic organisms.  

PubMed Central

This paper reviews current knowledge of biogeochemical cycles of pollutant organic chemicals in aquatic ecosystems with a focus on coastal ecosystems. There is a bias toward discussing chemical and geochemical aspects of biogeochemical cycles and an emphasis on hydrophobic organic compounds such as polynuclear aromatic hydrocarbons, polychlorinated biphenyls, and chlorinated organic compounds used as pesticides. The complexity of mixtures of pollutant organic compounds, their various modes of entering ecosystems, and their physical chemical forms are discussed. Important factors that influence bioavailability and disposition (e.g., organism-water partitioning, uptake via food, food web transfer) are reviewed. These factors include solubilities of chemicals; partitioning of chemicals between solid surfaces, colloids, and soluble phases; variables rates of sorption, desorption; and physiological status of organism. It appears that more emphasis on considering food as a source of uptake and bioaccumulation is important in benthic and epibenthic ecosystems when sediment-associated pollutants are a significant source of input to an aquatic ecosystem. Progress with mathematical models for exposure and uptake of contaminant chemicals is discussed briefly.

Farrington, J W

1991-01-01

206

Identifying organic nitrogen compounds in Rocky Mountain National Park aerosols  

NASA Astrophysics Data System (ADS)

Nitrogen deposition is an important issue in Rocky Mountain National Park (RMNP). While inorganic nitrogen contributions to the ecosystems in this area have been studied, the sources of organic nitrogen are still largely unknown. To better understand the potential sources of organic nitrogen, filter samples were collected and analyzed for organic nitrogen species. Samples were collected in RMNP using a Thermo Fisher Scientific TSP (total suspended particulate) high-volume sampler with a PM2.5 impactor plate from April - November of 2008. The samples presented the opportunity to compare two different methods for identification of individual organic nitrogen species. The first type of analysis was performed with a comprehensive two dimensional gas chromatography (GCxGC) system using a nitrogen chemiluminescence detector (NCD). The filter samples were spiked with propanil in dichloromethane to use as an internal standard and were then extracted in water followed by solid phase extraction. The GCxGC system was comprised of a volatility based separation (DB5 column) followed by a polarity based separation (RXI-17 column). A NCD was used to specifically detect nitrogen compounds and remove the complex background matrix. Individual standards were used to identify peaks by comparing retention times. This method has the added benefit of an equimolar response for nitrogen so only a single calibration is needed for all species. In the second analysis, a portion of the same filter samples were extracted in DI water and analyzed with liquid chromatography coupled with mass spectroscopy (LC/MS). The separation was performed using a C18 column and a water-methanol gradient elution. Electrospray ionization into a time of flight mass spectrometer was used for detection. High accuracy mass measurement allowed unambiguous assignments of elemental composition of resulting ions. Positive and negative polarities were used since amines tend to show up in positive mode and nitrates in negative. The differences in the number of species and what species are identified between these two methods are important for planning future analyses of organic nitrogen compounds. In addition, these data provide new insight into the potential source of organic nitrogen in RMNP. Using the GCxGC method, 39 organic nitrogen species were detected and 20 were identified. Identified species include several types of amines and phenols. The LC/MS method identified several types of cresols, amines, and nitrates.

Beem, K. B.; Desyaterik, Y.; Ozel, M. Z.; Hamilton, J. F.; Collett, J. L.

2010-12-01

207

Synthesis of Novel Organic-Inorganic Self-Organized Compounds Containing Quaternary Ammonium Ions and its Structural Characterization  

Microsoft Academic Search

Organic-inorganic layered perovskite compounds described by (RNH 3 ) 2 MX 4 [R: alkyl group, M: divalent metals, X: halogen] were reported to form self-organized quantum-well structures. In this study, we aimed to synthesize novel organic-inorganic self-organized compounds with quaternary ammonium ions instead of primary alkylammonium ions. New compounds, [(C 12 H 25 ) 2 (CH 3 ) 2 N]PbBr

Satoshi Kano; Kenjiro Teshima; Masahiro Rikukawa; Kohei Sanui

2002-01-01

208

Modeling Emissions of Volatile Organic Compounds from New Carpets  

SciTech Connect

A simple model is proposed to account for observed emissions of volatile organic compounds (VOCs) from new carpets. The model assumes that the VOCs originate predominantly in a uniform slab of polymer backing material. Parameters for the model (the initial concentration of a VOC in the polymer, a diffusion coefficient and an equilibrium polymer/air partition coefficient) are obtained from experimental data produced by a previous chamber study. The diffusion coefficients generally decrease as the molecular weight of the VOCs increase, while the polymer/air partition coefficients generally increase as the vapor pressure of the compounds decrease. In addition, for two of the study carpets that have a styrene-butadiene rubber (SBR) backing, the diffusion and partition coefficients are similar to independently reported values for SBR. The results suggest that predictions of VOCs emissions from new carpets may be possible based solely on a knowledge of the physical properties of the relevant compounds and the carpet backing material. However, a more rigorous validation of the model is desirable.

Little, J.C.; Hodgson, A.T.; Gadgil, A.J.

1993-02-01

209

Indoor chemistry. Ozone, volatile organic compounds, and carpets  

SciTech Connect

Volatile organic compounds (VOCs) have been measured in a freshly carpeted 20-m[sup 3] stainless-steel room in both the absence and presence of ozone (ozone concentrations ranging from 30 to 50 ppb, with one experiment conducted at 400 ppb). Four different types of carpeting were exposed, and in each set of experiments, the room was ventilated at 1 air exchange/h. The gas-phase concentrations of selected carpet emissions (e.g., 4-phenylcyclohexene, 4-vinylcyclohexene, and styrene) significantly decreased in the presence of ozone. Conversely, the concentrations of other compounds (e.g., formaldehyde, acetaldehyde, and aldehydes with between 5 and 10 carbons) significantly increased. Furthermore, the total concentration of VOCs increased markedly in the presence of ozone. The additional VOCs appear to have been generated by reactions between ozone and relatively nonvolatile compounds associated with the carpets. These studies suggest that VOCs measured within a building at elevated ozone levels (>30 ppb) may differ from those measured at lower ozone levels (<10 ppb). 12 refs., 2 figs., 6 tabs.

Weschler, C.J. (Bell Communications Research, Red Bank, NJ (United States)); Hodgson, A.T.; Wooley, J.D. (Lawrence Berkeley Lab., CA (United States))

1992-12-01

210

Degradation of volatile organic compounds with thermally activated persulfate oxidation.  

PubMed

This study investigated the extent and treatability of the degradation of 59 volatile organic compounds (VOCs) listed in the EPA SW-846 Method 8260B with thermally activated persulfate oxidation. Data on the degradation of the 59 VOCs (in mixture) reacted with sodium persulfate in concentrations of 1 g l(-1) and 5 g l(-1) and at temperatures of 20 degrees C, 30 degrees C, and 40 degrees C were obtained. The results indicate that persulfate oxidation mechanisms are effective in degrading many VOCs including chlorinated ethenes (CEs), BTEXs and trichloroethanes that are frequently detected in the subsurface at contaminated sites. Most of the targeted VOCs were rapidly degraded under the experimental conditions while some showed persistence to the persulfate oxidation. Compounds with "CC" bonds or with benzene rings bonded to reactive functional groups were readily degraded. Saturated hydrocarbons and halogenated alkanes were much more stable and difficult to degrade. For those highly persulfate-degradable VOCs, degradation was well fitted with a pseudo first-order decay model. Activation energies of reactions of CEs and BTEXs with persulfate were determined. The degradation rates increased with increasing reaction temperature and oxidant concentration. Nevertheless, to achieve complete degradation of persulfate-degradable compounds, the systems required sufficient amounts of persulfate to sustain the degradation reaction. PMID:16202809

Huang, Kun-Chang; Zhao, Zhiqiang; Hoag, George E; Dahmani, Amine; Block, Philip A

2005-04-12

211

[Discharge ion mobility spectrometry of ketonic organic compounds].  

PubMed

Ion mobility spectrometry (IMS) is a sensitive technique for fast on-line monitoring trace volatile organic compounds based upon the mobilities of gas phase ions at ambient pressure in weak electric field. In the present work, protonated water reactant ions were successfully prepared, and eight ketones were studied on a homemade high-resolution IMS apparatus using a discharge ionization source. The reduced mobility values of all ions were derived from the observed ion mobility spectra. The experimentally determined reduced mobilities for acetone, 2-butone, 1-methyl-2-pyrrolidinone acetophenone, cyclohexanone and product ions were compared with the previously reported values in the Ni-IMS, indicating that they are in good agreement. The reduced mobilities of methyl isopropyl ketone, 4-methyl-2-pentanone and cyclopentanone ions were given for the first time. The ionization process for organic compounds in the authors' discharge ion mobility spectrometer is suggested to be similar to Ni-IMS system, i.e., the proton transfer reactions produce protonated ketone ions. In addition, a linear correlation was found between the reduced mobilities of the ketone ions and their molecular masses. Qualitative measurements show that the limit of detection is in the ng x L(-1) order of magnitude in the authors' discharge ion mobility spectrometer. PMID:17655083

Huang, Guo-dong; Han, Hai-yan; Jia, Xian-de; Jin, Shun-ping; Li, Jian-quan; Wang, Hong-mei; Tang, Xiao-shuan; Jiang, Hai-he; Chu, Yan-nan; Zhou, Shi-kang

2007-05-01

212

Reactive uptake of organic compounds by liquid sulfuric acid.  

NASA Astrophysics Data System (ADS)

The uptake of several organic compounds by laboratory surrogates for tropospheric sulfuric acid particles were investigated by mass spectrometry and infrared reflection-absorption spectroscopy. Among the compounds studied were acetone [(CH_3)_2CO], 2,4-hexanedione [CH_3CO(CH_2)_2COCH_3, MBO], and 2-methyl-3-buten-2-ol [CH_2CHC(CH_3)_2OH]. Experiments were carried out on ultrathin sulfuric acid films (ca. 10-100 monolayer equivalents thick) as functions of organic partial pressure, temperature, and acid composition. Acetone uptake is irreversible for acids that contain >70 weight percent (wt. %) H_2SO4, with kinetics that are second-order in concentration of dissolved acetone. Hexanedione and MBO are irreversibly taken for all acid compositions investigated (60-96 wt. %), with first-order uptake kinetics. In all cases, the irreversible uptake is a consequence of sulfuric acid catalyzed reactions that lead to the formation of new C-C bonds. Implications of these results for heterogeneous tropospheric chemistry will be discussed.

Roberts, J.; Michelsen, R.

2003-04-01

213

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

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline...Terminals § 60.502 Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline...collection system designed to collect the total organic compounds vapors displaced from tank...

2013-07-01

214

Efficiency of organic compounds removal by electron-beam irradiation in presence of high metal concentration  

Microsoft Academic Search

The high efficiency of electron-beam irradiation process in removing organic compounds from industrial effluents has been established. The actual chemical, textile, pharmaceutical and industrial effluents contain a high level of organic and inorganic compounds. In this study, the organic compounds removal was evaluated in the simulated industrial effluents, using electron-beam irradiation. The samples were prepared by adding Na, Cl, Ca,

Celina L Duarte; Márcia A Ribeiro; Ivone M Sato; Maria Helena de O Sampa

2004-01-01

215

PRESENT STATUS AND PROSPECTS OF USING ORGANIC COMPOUNDS AS MODERATOR-HEAT CONDUCTORS IN ATOMIC REACTORS  

Microsoft Academic Search

Discussion is given on the use of organic compounds as moderator-heat ; conductors in nuclear reactors. The advantages of organic compounds over water ; are listed. However, organic compounds are harder to purify, have higher fusing ; points, are lower than water in heat exchange, and are vulnerable to destruction. ; Thus far tri-xenene mixtures have proved best for moderator-hent

1961-01-01

216

Origin and fate of organic compounds in water: characterization by compound-specific stable isotope analysis.  

PubMed

Within the past 15 years, compound-specific stable isotope analysis has continued to increase in popularity in the area of contaminant hydrology of organic molecules. In particular, in cases where concentration data alone are insufficient to elucidate environmental processes unequivocally, the isotope signature can provide additional unique information. Specifically, it can help answer questions about contaminant source apportionment, quantification of biotic and abiotic processes, and identification of transformation reactions on a mechanistic level. We review advances in laboratory and field investigations and exemplary applications in contaminant hydrology via stable isotope analysis. We also highlight future directions in the field. PMID:22482787

Schmidt, Torsten C; Jochmann, Maik A

2012-04-09

217

[Biological function of some elements and their compounds. II. Selenium, selenate, selenium organic compounds].  

PubMed

The review is devoted to the role of selenium and its compounds for living organisms. Selenium as an antioxidant protects the cells from generating free radicals. It constitutes an integral part of approximately 20 enzymes. Glutathione peroxidase, which participates in metabolism of H2O2 and plays a protective role against lipids oxidation is one of the most important enzymes containing of selenium. In organisms, selenium occurs most frequently in amino acids, where it replaces sulphur, such as selenocystein and selenometionine, as well as in bonds with proteins. Amino acid bonds are significant in functions of RNA, in biosynthesis and activity of thyroid hormones. Selenium deficiency leads to decrease in selenium-dependent glutathione peroxidase, which occurs in mitochondria and cytosole. It causes also heart muscles diseases, the skeletal and circulatory systems disorders, neoplasms, infections, and cold. PMID:19827742

Puzanowska-Tarasiewicz, Helena; Ku?micka, Ludmila; Tarasiewicz, Miros?aw

2009-09-01

218

On the flux of oxygenated volatile organic compounds from organic aerosol oxidation  

NASA Astrophysics Data System (ADS)

Previous laboratory and field studies suggest that oxidation of organic aerosols can be a source of oxygenated volatile organic compounds (OVOC). Using measurements of atmospheric oxidants and aerosol size distributions performed on the NASA DC-8 during the INTEX-NA campaign, we estimate the potential magnitude of the continental summertime OVOC flux from organic aerosol oxidation by OH to be as large as ~70 pptv C/day in the free troposphere. Contributions from O3, H2O2, photolysis, and other oxidants may increase this estimate. These processes may provide a large, diffuse source of OVOC that has not been included in current atmospheric models, and thus have a significant impact on our understanding of organic aerosol, OVOC, PAN, and HOx chemistry. The potential importance and highly uncertain nature of our estimate highlights the need for more field and laboratory studies on organic aerosol composition and aging.

Kwan, Alan J.; Crounse, John D.; Clarke, Antony D.; Shinozuka, Yohei; Anderson, Bruce E.; Crawford, James H.; Avery, Melody A.; McNaughton, Cameron S.; Brune, William H.; Singh, Hanwant B.; Wennberg, Paul O.

2006-08-01

219

Six hydrogen bond directed supramolecular adducts formed between racemic-bis-?-naphthol and N-containing aromatic bases  

NASA Astrophysics Data System (ADS)

Studies concentrating on hydrogen bonding between the base of exobidentate bis(imidazole) derivatives, and 2-aminoheterocyclic compounds, and (±)-1,10-binaphthalene-2,2?-diol have led to an increased understanding of the role the aromatic N-containing compounds have in binding with (±)-1,10-binaphthalene-2,2?-diol. Here anhydrous multicomponent adducts of N-containing aromatic bases such as 1,4-bis(N-imidazolyl)butane (L1), 1,3-bis(N-benzimidazolyl)propane (L2), 1,4-bis(N-benzimidazolyl)butane (L3), 1,5-bis(N-benzimidazolyl)-3-oxapentane (L4), 2-amino-4-phenylthiazole (L5), and 2-amino-5,7-dimethyl-1,8-naphthyridine (L6) have been prepared with (±)-1,10-binaphthalene-2,2?-diol (binol). The six crystalline forms reported are cocrystals of which the crystals and complexes were characterized by X-ray diffraction analysis, IR, mp, and elemental analysis. The inter-ring angles (naphthol/naphthol) in the same binol of the six cocrystals ranged from 70.71° to 104.2° as the organic bases varied. In the six cocrystals, the binols exist either as both of the enantiomers of rac-binol or as only of its single enantiomer. All supramolecular architectures of cocrystals 1-6 are stabilized by O-H\\ctdot N hydrogen bonds. In addition other non-conventional interactions (CH-?, CH3-?, NH-?, S-?, and ?-? interactions) play an important role in the solid-state packing of co-crystallization as well. These weak interactions combined, all of the six complexes displayed 3D network structure.

Jin, Shouwen; Dong, Qiong; Wang, Daqi; Zhou, Wei

2012-04-01

220

Prediction of the sorption of organic compounds into soil organic matter from molecular structure.  

PubMed

A new model to estimate the soil-water partition coefficient of non-ionic organic compounds normalized to soil organic carbon, Koc, from the two-dimensional molecular structure is presented. Literature data of log Koc for 571 organic chemicals were fitted to 29 parameters with a squared correlation coefficient r2 of 0.852 and a standard error of 0.469 log units. The application domain includes the atom types C, H, N, O, P, S, F, Cl, and Br in various important compound classes. The multilinear model contains the variables molecular weight, bond connectivity, molecular E-state, an indicator for nonpolar and weakly polar compounds, and 24 fragment corrections representing polar groups. The prediction capability is evaluated through an initial two-step development using an 80%:20% split of the data into training and prediction, cross-validation, permutation, and application to three external data sets. The discussion includes separate analyses for subsets of H-bond donors and acceptors as well as for nonpolar and weakly polar compounds. Comparison with existing models including linear solvation energy relationships illustrates the superiority of the new model. PMID:17154008

Schüürmann, Gerrit; Ebert, Ralf-Uwe; Kühne, Ralph

2006-11-15

221

Organic volatile sulfur compounds in inland aquatic systems  

SciTech Connect

The speciation, concentration, and fluxes of organic volatile sulfur compounds (VSCs) in a wide variety of inland aquatic systems wee studied. Dissolved VSCs were sparged from water samples, trapped cryogenically, and quantified by gas chromatograph equipped with a flame photometric detector. Species detected and mean surface water concentrations were: carbonyl sulfide (COS), 0.091-7.6 nM; methanethiol (MSH), undetected-180 nM; dimethyl sulfide (DMS), 0.48-1290 nM; carbon disulfide (CS[sub 2]), undetected-69 nM; dimethyl disulfide (DMDS), undetected-68 nM. The range in surface water concentrations of over five orders of magnitude was influenced principally by lake depth and sulfate concentration ([SO[sub 4][sup 2[minus

Richards, S.R.

1991-01-01

222

Residential pollutants and ventilation strategies: Volatile organic compounds and radon  

SciTech Connect

This paper reviews literature that reports investigations of residential ventilation and indoor air quality. Two important residential pollutant classes, volatile organic compounds and radon, are examined. A companion paper examines moisture and combustion pollutants. Control strategies recommended from the review include appropriate building design to prevent or limit the sources of the pollutants within the space, proper operation and maintenance to prevent adverse conditions from developing during the building's life and appropriate use of ventilation. The characteristics of these pollutant sources suggest that ventilation systems in residences should have several properties. They should have the extra capacity available to reduce short bursts of pollution, be located close to the expected source of the contamination, and be inexpensive. Mitigation of radon is technically a major success using a form of task ventilation. Whole-house ventilation is, at best, a secondary form of control of excess radon in residences.

Grimsrud, D.T.; Hadlich, D.E.

1999-07-01

223

Flux Measurements of Volatile Organic Compounds from an Urban Landscape  

SciTech Connect

Direct measurements of volatile organic compound (VOC) emissions that include all anthropogenic and biogenic emission sources in urban areas are a missing requirement to evaluate emission inventories and constrain current photochemical modelling practices. Here we demonstrate the use of micrometeorological techniques coupled with fast-response sensors to measure urban VOC fluxes from a neighborhood of Mexico City, where the spatial variability of surface cover and roughness is high. Fluxes of olefins, methanol, acetone, toluene and C2-benzenes were measured and compared with the local gridded emission inventory. VOC fluxes exhibited a clear diurnal pattern with a strong relationship to vehicular traffic. Recent photochemical modeling results suggest that VOC emissions are significantly underestimated in Mexico City1, but the measured VOC fluxes described here indicate that the official emission inventory2 is essentially correct. Thus, other explanations are needed to explain the photochemical modelling results.

Velasco, E.; Lamb, Brian K.; Pressley, S.; Allwine, Eugene J.; Westberg, Halvor; Jobson, B Tom T.; Alexander, M. Lizabeth; Prazeller, Peter; Molina, Luisa; Molina, Mario J.

2005-10-19

224

Biosynthesis, function and metabolic engineering of plant volatile organic compounds.  

PubMed

Plants synthesize an amazing diversity of volatile organic compounds (VOCs) that facilitate interactions with their environment, from attracting pollinators and seed dispersers to protecting themselves from pathogens, parasites and herbivores. Recent progress in -omics technologies resulted in the isolation of genes encoding enzymes responsible for the biosynthesis of many volatiles and contributed to our understanding of regulatory mechanisms involved in VOC formation. In this review, we largely focus on the biosynthesis and regulation of plant volatiles, the involvement of floral volatiles in plant reproduction as well as their contribution to plant biodiversity and applications in agriculture via crop-pollinator interactions. In addition, metabolic engineering approaches for both the improvement of plant defense and pollinator attraction are discussed in light of methodological constraints and ecological complications that limit the transition of crops with modified volatile profiles from research laboratories to real-world implementation. PMID:23383981

Dudareva, Natalia; Klempien, Antje; Muhlemann, Joëlle K; Kaplan, Ian

2013-02-06

225

Detection of volatile organic compounds using surface enhanced Raman scattering  

SciTech Connect

The authors present the detection of volatile organic compounds directly in their vapor phase by surface-enhanced Raman scattering (SERS) substrates based on lithographically-defined two-dimensional rectangular array of nanopillars. The type of nanopillars is known as the tapered pillars. For the tapered pillars, SERS enhancement arises from the nanofocusing effect due to the sharp tip on top. SERS experiments were carried out on these substrates using various concentrations of toluene vapor. The results show that SERS signal from a toluene vapor concentration of ppm level can be achieved, and the toluene vapor can be detected within minutes of exposing the SERS substrate to the vapor. A simple adsorption model is developed which gives results matching the experimental data. The results also show promising potential for the use of these substrates in environmental monitoring of gases and vapors.

Chang, A S; Maiti, A; Ileri, N; Bora, M; Larson, C C; Britten, J A; Bond, T C

2012-03-22

226

A novel nanostructure for ultrasensitive volatile organic compound sensing  

NASA Astrophysics Data System (ADS)

We have developed an arrayed nanocoaxial structure for the ultrasensitive sensing detection and identification of volatile organic compounds (VOC) by dielectric impedance spectroscopy. VOC molecules are absorbed into porous dielectric material in the annulus between nanoscale coax electrodes. A theoretical expression for the basic adsorption mechanism agrees with the experimental results. Detection sensitivities at parts-per-billion levels were demonstrated for a variety of VOCs. A limit-of-detection of ethanol reached ˜100 parts-per-trillion, following a Freundlich power-law isotherm across four decades of ethanol concentration. A linear dependence on VOC dielectric constant was observed. Dielectric impedance nanospectroscopy was also performed by scanning frequency from 10 mHz to 1 MHz, with distinctive spectra of different VOCs discovered. These were utilized to conduct colorimetric identification of VOCs. The results suggest our novel nanocoaxial sensor can be used as a sensitive, broadband, and multimodal sensing platform for chemical detection.

Zhao, Huaizhou; Rizal, Binod; Ren, Zhifeng; Naughton, Michael J.; Chiles, Thomas C.; Cai, Dong

2011-03-01

227

Field-usable portable analyzer for chlorinated organic compounds  

SciTech Connect

In 1992, a chemical sensor was developed which showed almost perfect selectivity to vapors of chlorinated solvents. When interfaced to an instrument, a chemical analyzer will be produced that has near- absolute selectivity to vapors of volatile chlorinated organic compounds. TRI has just completed the second of a 2-phase program to develop this new instrument system, which is called the RCL MONITOR. In Phase II, this instrument was deployed in 5 EM40 operations. Phase II applications covered clean-up process monitoring, environmental modeling, routine monitoring, health and safety, and technology validation. Vapor levels between 0 and 100 ppM can be determined in 90 s with a lower detection limit of 0.5 ppM using the hand-portable instrument. Based on the favorable performance of the RCL MONITOR, the commercial instrument was released for commercial sales on Sept. 20, 1996.

Buttner, W.J.; Penrose, W.R.; Stetter, J.R.; Williams, R.D.

1996-12-31

228

In situ bioremediation of petroleum hydrocarbon and other organic compounds  

SciTech Connect

From supertanker oil spills to the leaking underground storage tank at the corner gas station, contamination from petroleum hydrocarbon fuels and other organic compounds is an environmental concern that affects nearly every small hamlet and major metropolis throughout the world. Most petroleum hydrocarbons are amenable to biodegradation, and a considerable body of experience has been built up over the past two decades in applying in situ bioremediation to a variety of contaminants in all media. This volume provides a comprehensive guide to the latest technological breakthroughs in both the laboratory and the field, covering such topics as air sparging, co-metabolic biodegradation, treatment of MTBE, real-time control systems, nutrient addition, rapid biosensor analysis, multiphase extraction, and accelerated bioremediation.

Alleman, B.C.; Leeson, A.

1999-11-01

229

In situ bioremediation of petroleum hydrocarbon and other organic compounds  

SciTech Connect

From supertanker oil spills to the leaking underground storage tank at the corner gas station, contamination from petroleum hydrocarbon fuels and other organic compounds is an environmental concern that affects nearly every small hamlet and major metropolis throughout the world. Moreover, the world`s rivers, estuaries, and oceans are threatened by contamination from petroleum leaks and spills. Fortunately, most petroleum hydrocarbons are amenable to biodegradation, and a considerable body of experience has been built up over the past two decades in applying in situ bioremediation to a variety of contaminants in all media. Good progress is being made in terms of developing innovative, cost-effective in situ approaches to bioremediation. This volume provides a comprehensive guide to the latest technological breakthroughs in both the laboratory and the field, covering such topics as air sparging, cometabolic biodegradation, treatment of MTBE, real-time control systems, nutrient addition, rapid biosensor analysis, multiphase extraction, and accelerated bioremediation.

Alleman, B.C.; Leeson, A. [eds.

1999-10-01

230

In situ bioremediation of petroleum hydrocarbon and other organic compounds  

SciTech Connect

From supertanker oil spills to the leaking underground storage tank at the corner gas station, contamination from petroleum hydrocarbon fuels and other organic compounds is an environmental concern that affects nearly every small hamlet and major metropolis throughout the world. Most petroleum hydrocarbons are amenable to biodegradation, and a considerable body of experience has been built up over the past two decades in applying in situ bioremediation to a variety of contaminants in all media. This volume provides a comprehensive guide to the latest technological breakthroughs in both the laboratory and the field, covering such topics as air sparging, co-metabolic biodegradation, treatment of MTBE, real-time control systems, nutrient addition, rapid biosensor analysis, multiphase extraction, and accelerated bioremediation.

Alleman, B.C.; Leeson, A.

1999-01-01

231

Source apportionment of volatile organic compounds in Tehran, Iran.  

PubMed

Identifying the sources of volatile organic compounds (VOCs) is key issue to reducing ground-level ozone and PAN. A multivariate receptor model (Unmix) was used for the determination of the contributions of VOCs sources in Tehran-Iran. Concentrations of ambient C2-C10 VOCs were measured continuously and online at the center of Tehran city during the winter of 2012. A high correlation coefficient existed between measured and predicted values (R (2) = 0.99), indicating that the data were well modeled. Five possible VOCs source categories were identified and mobile sources such as vehicle exhaust (61 %) and fuel evaporation (12 %) more than half of the total VOC concentration. City gas and CNG sources, biogenic source, and industrial solvent source categories accounted for 17 %, 8 % and 2 % of the total VOC, respectively. Result showed Unmix for VOCs source apportionment can be used to analyze and generate air pollution control strategies and policies. PMID:23283536

Sarkhosh, Maryam; Mahvi, Amir Hossein; Yunesian, Masud; Nabizadeh, Ramin; Borji, Saeedeh Hemmati; Bajgirani, Ali Ghiami

2013-01-03

232

Volatile Organic Compound Emissions from Dairy Facilities in Central California  

NASA Astrophysics Data System (ADS)

Emissions of volatile organic compounds (VOCs) from dairy facilities are thought to be an important contributor to high ozone levels in Central California, but emissions inventories from these sources contain significant uncertainties. In this work, VOC emissions were measured at two Central California dairies during 2010 and 2011. Isolation flux chambers were used to measure direct emissions from specific dairy sources, and upwind/downwind ambient profiles were measured from ground level up to heights of 60 m. Samples were collected using a combination of canisters and sorbent tubes, and were analyzed by GC-MS. Additional in-situ measurements were made using infra-red photoaccoustic detectors and Diode Laser Absorption Spectroscopy. Temperature and ozone profiles up to 250 m above ground level were also measured using a tethersonde. Substantial fluxes of a number of VOCs including alcohols, volatile fatty acids and esters were observed at both sites. Implications of these measurements for regional air quality will be discussed.

Hasson, A. S.; Ogunjemiyo, S. O.; Trabue, S.; Middala, S. R.; Ashkan, S.; Scoggin, K.; Vu, K. K.; Addala, L.; Olea, C.; Nana, L.; Scruggs, A. K.; Steele, J.; Shelton, T. C.; Osborne, B.; McHenry, J. R.

2011-12-01

233

Solid-phase genotoxicity assay for organic compounds in soil  

SciTech Connect

A genotoxicity assay was developed for samples from environments in which toxic organic compounds are largely sorbed. The assay entails measurement of the rate of mutation of a strain of Pseudomonas putida to rifampicin resistance. The ratio of induced to spontaneous mutants was a function of the concentration of a test mutagen in soil. In studies of the utility of the assay in samples amended with 2-aminofluorene as a test mutagen, the ratio of induced to spontaneous mutants declined with time. The decline paralleled the disappearance of extractable 2-aminofluorene from the soil. The ratio of induced to spontaneous mutants also feel in four other soils with dissimilar properties. The authors suggest that this solid-phase assay is more appropriate for the estimation of genotoxicants sorbed in soil than assays involving extractants or suspensions of soil or sediment samples.

Alexander, R.R.; Chung, N.; Alexander, M. [Cornell Univ., Ithaca, NY (United States)

1999-03-01

234

Membrane bioreactor for control of volatile organic compound emissions  

SciTech Connect

A membrane bioreactor system that overcomes many of the limitations of conventional compost biofilters is described. The system utilizes microporous hydrophobic hollow fiber membranes for mass transfer of volatile organic compounds (VOCs) from the gas phase to a microbially active liquid phase. The reactor design provides a high biomass concentration, a method for wasting biomass, and a method for addition of pH buffers, nutrients, cometabolites, and/or other amendments. A theoretical model is developed, describing mass transfer and biodegradation in the membrane bioreactor. Reactor performance was determined in a laboratory scale membrane bioreactor over a range of gas loading rates using toluene as a model VOC. Toluene removal efficiency was greater than 98% at an inlet concentration of 100 ppm, and a gas residence time of less than 2 s. Factors controlling bioreactor performance were determined through both experiments and theoretical modeling to include: compound Henry`s law constant, membrane specific surface area, gas and VOC loading rates, liquid phase turbulence, and biomass substrate utilization rate.

Ergas, S.J. [Univ. of Massachusetts, Amherst, MA (United States). Dept. of Civil and Environmental Engineering; McGrath, M.S. [Monsanto Enviro-Chem Systems Inc., Chesterfield, MO (United States)

1997-06-01

235

Constituents of volatile organic compounds of evaporating essential oil  

NASA Astrophysics Data System (ADS)

Essential oils containing aromatic compounds can affect air quality when used indoors. Five typical and popular essential oils—rose, lemon, rosemary, tea tree and lavender—were investigated in terms of composition, thermal characteristics, volatile organic compound (VOC) constituents, and emission factors. The activation energy was 6.3-8.6 kcal mol -1, the reaction order was in the range of 0.6-0.8, and the frequency factor was 0.01-0.24 min -1. Toluene, 1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene, n-undecane, p-diethylbenzene and m-diethylbenzene were the predominant VOCs of evaporating gas of essential oils at 40 °C. In addition, n-undecane, p-diethylbenzene, 1,2,4-trimethylbenzene, m-diethylbenzene, and 1,2,3-trimethylbenzene revealed high emission factors during the thermogravimetric (TG) analysis procedures. The sequence of the emission factors of 52 VOCs (137-173 mg g -1) was rose ? rosemary > tea tree ? lemon ? lavender. The VOC group fraction of the emission factor of aromatics was 62-78%, paraffins were 21-37% and olefins were less than 1.5% during the TG process. Some unhealthy VOCs such as benzene and toluene were measured at low temperature; they reveal the potential effect on indoor air quality and human health.

Chiu, Hua-Hsien; Chiang, Hsiu-Mei; Lo, Cho-Ching; Chen, Ching-Yen; Chiang, Hung-Lung

2009-12-01

236

Source characteristics of oxygenated volatile organic compounds and hydrogen cyanide  

NASA Astrophysics Data System (ADS)

Airborne trace gas measurements from Transport and Chemical Evolution over the Pacific (TRACE-P), Pacific Exploratory Mission (PEM)-Tropics B, and Intercontinental Chemical Transport Experiment-North America (INTEX-NA) experiments are analyzed to examine the major source factors contributing to the observed variabilities of oxygenated volatile organic compounds and cyanides. The positive matrix factorization method is applied to coincident measurements of 11 chemicals including CH3OH, CH3COCH3, CH3CHO, C2H2, C2H6, i-C5H12, CO, CH3Cl, and CHBr3. Measurements of HCN and CH3CN are available for TRACE-P and INTEX-NA. We identify major source contributions from the terrestrial biosphere, biomass burning, industry/urban regions, and oceans. Spatial and back trajectory characteristics of these factors are examined. On the basis of TRACE-P and PEM-Tropics B data, we find a factor that explains 80-88% of the CH3OH variability, 20-40% of CH3COCH3, 7-35% of CH3CHO, and 41% of HCN, most likely representing the emissions from terrestrial biosphere. Our analysis suggested that biogenic emissions of HCN may be significant. Cyanogenesis in plants is likely a major emission process for HCN, which was not fully accounted for previously. Larger contributions than previous global estimations to CH3COCH3 and CH3CHO by biomass burning and industry/urban sources likely reflect significant secondary production from volatile organic compound oxidation. No evidence was found for large emissions of CH3COCH3 from the ocean. The oceanic CH3CHO contribution implies large regional variations.

Shim, Changsub; Wang, Yuhang; Singh, Hanwant B.; Blake, Donald R.; Guenther, Alex B.

2007-05-01

237

Source characteristics of oxygenated volatile organic compounds and hydrogen cyanide  

NASA Astrophysics Data System (ADS)

Airborne trace gas measurements from TRACE-P, PEM-Tropics B, and INTEX-NA experiments are analyzed to examine the major source factors contributing to the observed variabilities of oxygenated volatile organic compounds and cyanides. Positive matrix factorization (PMF) is applied to coincident measurements of 11 chemicals including CH3OH, CH3COCH3, CH3CHO, C2H2, C2H6, i-C5H12, CO, CH3Cl, and CHBr3. Measurements of HCN and CH3CN are available for TRACE-P and INTEX-NA. We identify major source contributions from the terrestrial biosphere, biomass burning, industry/urban regions, and oceans. Spatial and backtrajectory characteristics of these factors are examined. Based on TRACE-P and PEM-Tropics B data, we find that the terrestrial biogenic factor explains 80-88% of the CH3OH variability, 20-40% of CH3COCH3, 7-35% of CH3CHO, and 41% of HCN. The biogenic contribution to HCN derived from this analysis is much larger than previous global estimates. Cyanogenesis in plants is likely a major emission process for HCN, not fully accounted for previously. Larger contributions than previous global estimations to CH3COCH3 and CH3CHO by biomass burning and industry/urban sources likely reflect significant secondary production from volatile organic compounds (VOC) oxidation. No evidence was found for large emissions of CH3COCH3 from the ocean. The oceanic CH3CHO contribution implies large regional variations.

Wang, Y.; Shim, C.; Singh, H.; Blake, D.; Guenther, A.

2006-12-01

238

40 CFR Table 1 to Subpart D of... - Volatile Organic Compound (VOC), Content Limits for Architectural Coatings  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Volatile Organic Compound (VOC), Content Limits for...PROGRAMS (CONTINUED) NATIONAL VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards for...

2013-07-01

239

40 CFR Table 1 to Subpart B of... - Volatile Organic Compound (VOC) Content Limits for Automobile Refinish Coatings  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Volatile Organic Compound (VOC) Content Limits for Automobile...PROGRAMS (CONTINUED) NATIONAL VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards for...

2013-07-01

240

40 CFR Table 1 to Subpart B of... - Volatile Organic Compound (VOC) Content Limits for Automobile Refinish Coatings  

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Volatile Organic Compound (VOC) Content Limits for Automobile...CONTINUED) NATIONAL VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards for Automobile...

2009-07-01

241

40 CFR Table 1 to Subpart D of... - Volatile Organic Compound (VOC), Content Limits for Architectural Coatings  

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Volatile Organic Compound (VOC), Content Limits for Architectural...CONTINUED) NATIONAL VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards for...

2009-07-01

242

40 CFR Table 1 to Subpart D of... - Volatile Organic Compound (VOC), Content Limits for Architectural Coatings  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Volatile Organic Compound (VOC), Content Limits for Architectural...CONTINUED) NATIONAL VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards for...

2010-07-01

243

Exchange of volatile organic compounds in the boreal forest floor  

NASA Astrophysics Data System (ADS)

Terrestrial ecosystems, mainly plants, emit large amounts of volatile organic compounds (VOCs) into the atmosphere. In addition to plants, VOCs also have less-known sources, such as soil. VOCs are a very diverse group of reactive compounds, including terpenoids, alcohols, aldehydes and ketones. Due to their high reactivity, VOCs take part in formation and growth of secondary organic aerosols in the atmosphere and thus affect also Earth's radiation balance (Kulmala et al. 2004). We have studied boreal soil and forest floor VOC fluxes with chamber and snow gradient techniques we were developed. Spatial and temporal variability in VOC fluxes was studied with year-round measurements in the field and the sources of boreal soil VOCs in the laboratory with fungal isolates. Determination of the compounds was performed mass spectrometrically. Our results reveal that VOCs from soil are mainly emitted by living roots, above- and belowground litter and microbes. The strongest source appears to be litter, in which both plant residuals and decomposers play a role in the emissions. Soil fungi showed high emissions of lighter VOCs, like acetone, acetaldehyde and methanol, from isolates. Temperature and moisture are the most critical physical factors driving VOC fluxes. Since the environment in boreal forests undergoes strong seasonal changes, the VOC flux strength of the forest floor varies markedly during the year, being highest in spring and autumn. The high spatial heterogeneity of the forest floor was also clearly visible in VOC fluxes. The fluxes of other trace gases (CO2, CH4 and N2O) from soil, which are also related to the soil biological activity and physical conditions, did not show correlations with the VOC fluxes. These results indicate that emissions of VOCs from the boreal forest floor account for as much as several tens of percent, depending on the season, of the total forest ecosystem VOC emissions. This emphasises that forest floor compartment should be taken into consideration when assessing ecosystem level VOC fluxes. These results can be utilized also in air chemistry models, which are almost entirely lacking the below-canopy compartment. Kulmala, M., Suni, T., Lehtinen, K.E.J., Dal Maso, M., Boy, M., Reissell, A., Rannik, Ü., Aalto, P., Keronen, P., Hakola, H., Bäck, J., Hoffmann, T., Vesala, T. & Hari, P. 2004. A new feedback mechanism linking forests, aerosols, and climate. Atmospheric Chemistry and Physics 4: 557-562.

Aaltonen, Hermanni; Bäck, Jaana; Pumpanen, Jukka; Pihlatie, Mari; Hakola, Hannele; Hellén, Heidi; Aalto, Juho; Heinonsalo, Jussi; Kajos, Maija K.; Kolari, Pasi; Taipale, Risto; Vesala, Timo

2013-04-01

244

A biogenic volatile organic compound emission inventory for Hong Kong  

NASA Astrophysics Data System (ADS)

Biogenic volatile organic compounds (BVOCs) in the atmosphere react to form ozone and secondary organic aerosols, which deteriorate air quality, affect human health, and indirectly influence global climate changes. The present study aims to provide a preliminary assessment of BVOC emissions in Hong Kong (HKSAR). Thriteen local tree species were measured for their isoprene emission potential. Tree distribution was estimated for country park areas based on field survey data. Plant emission data obtained from measurements and the literature, tree distribution estimation data, land use information, and meteorological data were combined to estimate annual BVOC emissions of 8.6×10 9 g C for Hong Kong. Isoprene, monoterpenes, and other VOCs contributed about 30%, 40%, and 30% of the estimated total annual emissions, respectively. Although hundreds of plant species are found in Hong Kong country parks, the model results indicate that only 10 tree species contribute about 76% of total annual VOC emissions. Prominent seasonal and diurnal variations in emissions were also predicted by the model. The present study lays a solid foundation for future local research, and results can be applied for studying BVOC emissions in nearby southern China and Asian regions that share similar climate and plant distributions.

Tsui, Jeanie Kin-Yin; Guenther, Alex; Yip, Wing-Kin; Chen, Feng

245

Emerging site characterization technologies for volatile organic compounds  

SciTech Connect

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.

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

1992-05-01

246

Emerging site characterization technologies for volatile organic compounds  

SciTech Connect

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.

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

1992-05-01

247

[Volatile organic compounds (VOCs) emitted from furniture and electrical appliances].  

PubMed

Organic chemicals are widely used as ingredients in household products. Therefore, furniture and other household products as well as building products may influence the indoor air quality. This study was performed to estimate quantitatively influence of household products on indoor air quality. Volatile organic compound (VOC) emissions were investigated for 10 products including furniture (chest, desk, dining table, sofa, cupboard) and electrical appliances (refrigerator, electric heater, desktop personal computer, liquid crystal display television and audio) by the large chamber test method (JIS A 1912) under the standard conditions of 28 degrees C, 50% relative humidity and 0.5 times/h ventilation. Emission rate of total VOC (TVOC) from the sofa showed the highest; over 7900 microg toluene-equivalent/unit/h. Relatively high TVOC emissions were observed also from desk and chest. Based on the emission rates, the impacts on the indoor TVOC were estimated by the simple model with a volume of 17.4 m3 and ventilation frequency of 0.5 times/h. The estimated TVOC increment for the sofa was 911 microg/m3, accounting for almost 230% of the provisional target value, 400 microg/m3. The values of estimated increment of toluene emitted from cupboard and styrene emitted from refrigerator were 10% and 16% of guideline values, respectively. These results revealed that VOC emissions from household products may influence significantly indoor air quality. PMID:21381398

Tanaka-Kagawa, Toshiko; Jinno, Hideto; Furukawa, Yoko; Nishimura, Tetsuji

2010-01-01

248

Contributions of individual reactive biogenic volatile organic compounds to organic nitrates above a mixed forest  

NASA Astrophysics Data System (ADS)

Biogenic volatile organic compounds (BVOCs) can react in the atmosphere to form organic nitrates, which serve as NOx (NO + NO2) reservoirs, impacting ozone and secondary organic aerosol production, the oxidative capacity of the atmosphere, and nitrogen availability to ecosystems. To examine the contributions of biogenic emissions and the formation and fate of organic nitrates in a forest environment, we simulated the oxidation of 57 individual BVOCs emitted from a rural mixed forest in northern Michigan. Key BVOC-oxidant reactions were identified for future laboratory and field investigations into reaction rate constants, yields, and speciation of oxidation products. Of the total simulated organic nitrates, monoterpenes contributed ~70% in the early morning at ~12 m above the forest canopy when isoprene emissions were low. In the afternoon, when vertical mixing and isoprene nitrate production were highest, the simulated contribution of isoprene-derived organic nitrates was greater than 90% at all altitudes, with the concentration of secondary isoprene nitrates increasing with altitude. Notably, reaction of isoprene with NO3 leading to isoprene nitrate formation was found to be significant (~8% of primary organic nitrate production) during the daytime, and monoterpene reactions with NO3 were simulated to comprise up to ~83% of primary organic nitrate production at night. Lastly, forest succession, wherein aspen trees are being replaced by pine and maple trees, was predicted to lead to increased afternoon concentrations of monoterpene-derived organic nitrates. This further underscores the need to understand the formation and fate of these species, which have different chemical pathways and oxidation products compared to isoprene-derived organic nitrates and can lead to secondary organic aerosol formation.

Pratt, K. A.; Mielke, L. H.; Shepson, P. B.; Bryan, A. M.; Steiner, A. L.; Ortega, J.; Daly, R.; Helmig, D.; Vogel, C. S.; Griffith, S.; Dusanter, S.; Stevens, P. S.; Alaghmand, M.

2012-11-01

249

Sorption to soil of hydrophobic and ionic organic compounds: measurement and modeling  

Microsoft Academic Search

The sorption of organic compounds to soil, sediments and dissolved organic matter affects the fate of organic compounds. Given the central role of this process in environmental transport, distribution, and (bio)degradation processes, it needs to be well-understood and represented in risk assessment of chemicals in the environment. In this thesis soil-sorption of various organic compounds was studied in order to

Thomas Laurens ter Laak

2005-01-01

250

Chemical compound containing a superoxide scavenger and an organic nitrate or nitrite moiety  

US Patent & Trademark Office Database

Compounds for use in the treatment of heart disease include a superoxide scavenger and an organic nitrate or nitrite moiety. The compounds can be represented by the formula (A)n(B)m, in which A is a superoxide scavenger, B is an organic nitrate or organic nitrite moiety, and n and m are values between 1 and 8. These compounds do not suffer from the problem of patient tolerance that is associated with the use of conventional agents such as organic nitrates.

Zhang; Zhi (London, GB); Naughton; Declan P. (Brighton, GB); Sumi; Yoshihiko (Tokyo, JP); Imaizumi; Atsushi (Tokyo, JP)

2002-02-12

251

Carbonaceous meteorites as a source of sugar-related organic compounds for the early Earth  

Microsoft Academic Search

The much-studied Murchison meteorite is generally used as the standard reference for organic compounds in extraterrestrial material. Amino acids and other organic compounds important in contemporary biochemistry are thought to have been delivered to the early Earth by asteroids and comets, where they may have played a role in the origin of life. Polyhydroxylated compounds (polyols) such as sugars, sugar

George Cooper; Novelle Kimmich; Warren Belisle; Josh Sarinana; Katrina Brabham; Laurence Garrel

2001-01-01

252

Bioactive volatile organic compounds from Antarctic (sponges) bacteria.  

PubMed

Antarctic bacteria represent a reservoir of unexplored biodiversity, which, in turn, might be correlated to the synthesis of still undescribed bioactive molecules, such as antibiotics. In this work we have further characterized a panel of four marine Antarctic bacteria able to inhibit the growth of human opportunistic multiresistant pathogenic bacteria belonging to the Burkholderia cepacia complex (responsible for the 'cepacia' syndrome in Cystic Fibrosis patients) through the production of a set of microbial Volatile Organic Compounds (mVOCs). A list of 30 different mVOCs synthesized under aerobic conditions by Antarctic bacteria was identified by GC-SPME analysis. Cross-streaking experiments suggested that Antarctic bacteria might also synthesize non-volatile molecules able to enhance the anti-Burkholderia activity. The biosynthesis of such a mixture of mVOCs was very probably influenced by both the presence/absence of oxygen and the composition of media used to grow the Antarctic strains. The antimicrobial activity exhibited by Antarctic strains also appeared to be more related to their taxonomical position rather than to the sampling site. Different Bcc bacteria were differently sensitive to the 'Antarctic' mVOCs and this was apparently related neither to the taxonomical position of the different strains nor to their source. The genome sequence of three new Antarctic strains was determined revealing that only P. atlantica TB41 possesses some genes belonging to the nrps-pks cluster. The comparative genomic analysis performed on the genome of the four strains also revealed the presence of a few genes belonging to the core genome and involved in the secondary metabolites biosynthesis. Data obtained suggest that the antimicrobial activity exhibited by Antarctic bacteria might rely on a (complex) mixture of mVOCs whose relative concentration may vary depending on the growth conditions. Besides, it is also possible that the biosynthesis of these compounds might occur through still unknown metabolic pathways. PMID:23619351

Papaleo, Maria Cristiana; Romoli, Riccardo; Bartolucci, Gianluca; Maida, Isabel; Perrin, Elena; Fondi, Marco; Orlandini, Valerio; Mengoni, Alessio; Emiliani, Giovanni; Tutino, Maria Luisa; Parrilli, Ermenegilda; de Pascale, Donatella; Michaud, Luigi; Lo Giudice, Angelina; Fani, Renato

2013-04-22

253

A global model of natural volatile organic compound emissions  

NASA Astrophysics Data System (ADS)

Numerical assessments of global air quality and potential changes in atmospheric chemical constituents require estimates of the surface fluxes of a variety of trace gas species. We have developed a global model to estimate emissions of volatile organic compounds from natural sources (NVOC). Methane is not considered here and has been reviewed in detail elsewhere. The model has a highly resolved spatial grid (0.5°×0.5° latitude/longitude) and generates hourly average emission estimates. Chemical species are grouped into four categories: isoprene, monoterpenes, other reactive VOC (ORVOC), and other VOC (OVOC). NVOC emissions from oceans are estimated as a function of geophysical variables from a general circulation model and ocean color satellite data. Emissions from plant foliage are estimated from ecosystem specific biomass and emission factors and algorithms describing light and temperature dependence of NVOC emissions. Foliar density estimates are based on climatic variables and satellite data. Temporal variations in the model are driven by monthly estimates of biomass and temperature and hourly light estimates. The annual global VOC flux is estimated to be 1150 Tg C, composed of 44% isoprene, 11% monoterpenes, 22.5% other reactive VOC, and 22.5% other VOC. Large uncertainties exist for each of these estimates and particularly for compounds other than isoprene and monoterpenes. Tropical woodlands (rain forest, seasonal, drought-deciduous, and savanna) contribute about half of all global natural VOC emissions. Croplands, shrublands and other woodlands contribute 10-20% apiece. Isoprene emissions calculated for temperate regions are as much as a factor of 5 higher than previous estimates.

Guenther, Alex; Hewitt, C. Nicholas; Erickson, David; Fall, Ray; Geron, Chris; Graedel, Tom; Harley, Peter; Klinger, Lee; Lerdau, Manuel; McKay, W. A.; Pierce, Tom; Scholes, Bob; Steinbrecher, Rainer; Tallamraju, Raja; Taylor, John; Zimmerman, Pat

1995-05-01

254

Quantum Magnetism and possible BEC in an organic Nickel compound  

NASA Astrophysics Data System (ADS)

I will review recent experimental and theoretical work on the S=1 quantum magnet, NiCl2-4SC(NH2)2. [1] This compound exhibits field-induced XY antiferromagnetism for magnetic fields along the tetragonal c-axis between Hc1 = 2.1 and Hc2 = 12.6 T. The axial symmetry of the spin environment allows us to understand the quantum phase transitions at Hc1 and Hc2 in terms of Bose-Einstein condensation (BEC) of spin levels. Here the tuning parameter for BEC transition is the magnetic field and not the temperature. Specific heat, magnetocaloric effect, and magnetization data at low temperatures confirm the predicted behavior for a BEC: Hc-Hc1˜ T^? and M(Hc1) ˜ T^? where ? = 3/2. I will also present magnetostriction data [2] taken at dilution refrigerator temperatures that show significant magnetoelastic coupling and magnetic-order-induced modifications of the lattice parameters in this soft organic compound. The data are well-described by Quantum Monte Carlo calculations, allowing us to make a quantitative determination of the magnetoelastic coupling, and also extract the spin-spin correlation function from the magnetostriction data. [1] V. S. Zapf, D. Zocco, B. R. Hansen, M. Jaime, N. Harrison, C. D. Batista, M. Kenzelmann, C. Niedermayer, A. Lacerda, and A. Paduan-Filho, Phys. Rev. Lett. 96, 077204 (2006).[2] V. S. Zapf, V. Correa, C. D. Batista, T. Murphy, E. D. Palm, M. Jaime, S. Tozer, A. Lacerda, A. Paduan-Filho, ``Magnetostriction in the Bose-Einstein Condensate quantum magnet NiCl2-4SC(NH2)2,'' cond-mat/0611229.

Zapf, Vivien

2007-03-01

255

Selective Sorption of Dissolved Organic Carbon Compounds by Temperate Soils  

PubMed Central

Background Physico-chemical sorption onto soil minerals is one of the major processes of dissolved organic carbon (OC) stabilization in deeper soils. The interaction of DOC on soil solids is related to the reactivity of soil minerals, the chemistry of sorbate functional groups, and the stability of sorbate to microbial degradation. This study was conducted to examine the sorption of diverse OC compounds (D-glucose, L-alanine, oxalic acid, salicylic acid, and sinapyl alcohol) on temperate climate soil orders (Mollisols, Ultisols and Alfisols). Methodology Equilibrium batch experiments were conducted using 0–100 mg C L?1 at a solid-solution ratio of 1?60 for 48 hrs on natural soils and on soils sterilized by ?-irradiation. The maximum sorption capacity, Qmax and binding coefficient, k were calculated by fitting to the Langmuir model. Results Ultisols appeared to sorb more glucose, alanine, and salicylic acid than did Alfisols or Mollisols and the isotherms followed a non-linear pattern (higher k). Sterile experiments revealed that glucose and alanine were both readily degraded and/or incorporated into microbial biomass because the observed Qmax under sterile conditions decreased by 22–46% for glucose and 17–77% for alanine as compared to non-sterile conditions. Mollisols, in contrast, more readily reacted with oxalic acid (Qmax of 886 mg kg?1) and sinapyl alcohol (Qmax of 2031 mg kg?1), and no degradation was observed. The reactivity of Alfisols to DOC was intermediate to that of Ultisols and Mollisols, and degradation followed similar patterns as for Ultisols. Conclusion This study demonstrated that three common temperate soil orders experienced differential sorption and degradation of simple OC compounds, indicating that sorbate chemistry plays a significant role in the sorptive stabilization of DOC.

Jagadamma, Sindhu; Mayes, Melanie A.; Phillips, Jana R.

2012-01-01

256

Solubility of volatile organic compounds in aqueous ammonia solution.  

PubMed

The Ostwald solubility coefficient, L of 17 volatile organic compounds (VOCs) from the gas phase into water and dilute aqueous ammonia solutions was determined by the equilibrium partitioning in closed system-solid phase micro extraction (EPICS-SPME) method at 303 K and at 0-2.5 mol dm(-3) ammonia concentrations. Ammonia increased the solubility of all VOCs nearly linearly, but to a different extent. The difference in the solubility values in aqueous ammonia solutions (Lmix) compared to pure water (L) is explained on the basis of a Linear Solvation Energy Relationship (LSER) equation made applicable for solvent mixtures, logLmix - logL = x((sNH3 - sH2O)pi2H + (aNH3 - aH2O)Sigma2H + (bNH3 - bH2O)Sigmabeta2H + (vNH3 - VH2O)Vx). sNH3 - sH2O, aNH3 - aH2O, bNH3 - bH2O, vNH3 - vH2O are the differences of solvent parameters, x is the mole fraction, pi2H is the solute dipolarity-polarizability, Sigmaalpha2H is the effective hydrogen bond acidity of the solute, Sigmabeta2H is the effective hydrogen bond basicity of the solute and Vx, the McGowan characteristic volume. The most significant term was v, the phase hydrophobicity. The solubility behavior was explained by the change in structure of the aqueous solution: the presence of ammonia reduces the cavity effect. These findings show that the presence of compounds such as ammonia, frequently observed in environmental waters, especially wastewaters, affect the fugacity of VOCs, having consequences for the environmental partitioning of VOCs and having technical consequences towards wastewater treatment technologies. PMID:15833481

Görgényi, Miklós; Dewulf, Jo; Van Langenhove, Herman; Király, Zoltán

2005-05-01

257

Secondary organic aerosol formation from intermediate-volatility organic compounds: cyclic, linear, and branched alkanes.  

PubMed

Intermediate volatility organic compounds (IVOCs) are an important class of secondary organic aerosol (SOA) precursors that have not been traditionally included in chemical transport models. A challenge is that the vast majority of IVOCs cannot be speciated using traditional gas chromatography-based techniques; instead they are classified as an unresolved complex mixture (UCM) that is presumably made up of a complex mixture of branched and cyclic alkanes. To better understand SOA formation from IVOCs, a series of smog chamber experiments was conducted with different alkanes, including cyclic, branched, and linear compounds. The experiments focused on freshly formed SOA from hydroxyl (OH) radical-initiated reactions under high-NO(x) conditions at typical atmospheric organic aerosol concentrations (C(OA)). SOA yields from cyclic alkanes were comparable to yields from linear alkanes three to four carbons larger in size. For alkanes with equivalent carbon numbers, branched alkanes had the lowest SOA mass yields, ranging between 0.05 and 0.08 at a C(OA) of 15 ?g m(-3). The SOA yield of branched alkanes also depends on the methyl branch position on the carbon backbone. High-resolution aerosol mass spectrometer data indicate that the SOA oxygen-to-carbon ratios were largely controlled by the carbon number of the precursor compound. Depending on the precursor size, the mass spectrum of SOA produced from IVOCs is similar to the semivolatile-oxygenated and hydrocarbon-like organic aerosol factors derived from ambient data. Using the new yield data, we estimated SOA formation potential from diesel exhaust and predict the contribution from UCM vapors to be nearly four times larger than the contribution from single-ring aromatics and comparable to that of polycyclic aromatic hydrocarbons after several hours of oxidation at typical atmospheric conditions. Therefore, SOA from IVOCs may be an important contributor to urban OA and should be included in SOA models; the yield data presented in this study are suitable for such use. PMID:22823284

Tkacik, Daniel S; Presto, Albert A; Donahue, Neil M; Robinson, Allen L

2012-08-09

258

Controlled exposures to volatile organic compounds in sensitive groups.  

PubMed

Sensitivities to chemicals are characterized by symptoms in multiple organ systems in response to low-level chemical exposures. This paper reviews studies of controlled exposures to odorants and to mixtures of volatile organic compounds. Sensitive subgroups include subjects who met Cullen's 1987 criteria for multiple chemical sensitivity (MCS), Gulf War veterans with chronic fatigue syndrome and chemical sensitivity (CFS/CS), and subjects with specific self-reported sensitivities to methyl terbutyl ether (MTBE) in gasoline (MTBE-sensitive). All studies include comparison of age- and sex-matched healthy controls. Studies of olfaction did not support unusual sensitivity, defined as lower odor thresholds, among MCS subjects; however, a dose-response pattern of symptoms was observed in response to suprathreshold concentrations of phenyl ethyl alcohol. In blinded, controlled exposures to clean air, gasoline, gasoline/11% MTBE, and gasoline/15% MTBE, a threshold effect was observed with MTBE-sensitive subjects reporting significantly increased symptoms to gasoline/15% MTBE exposure. Autonomic arousal (heart and respiration rate; end-tidal CO2) in response to odor of chemical mixtures may mediate symptoms for subjects with generalized chemical sensitivities, but not for those whose sensitivities are confined to specific chemicals. For example, Gulf War veterans with CFS/CS experienced reduced end-tidal CO2 when exposed to diesel fumes, while exposure to MTBE did not produce any psychophysiologic changes in MTBE-sensitive subjects. Controlled olfactory and exposure studies reveal that significant responses can be observed in chemically sensitive subjects even when de-adaptation has not occurred. However, these studies suggest that symptoms are not necessarily accompanied by changes in physiologic arousal. Subject characteristics play a critical role in outcomes. PMID:12000025

Fiedler, N; Kipen, H M

2001-03-01

259

Field-usable portable analyzer for chlorinated organic compounds  

SciTech Connect

Transducer Research, Inc. (TRI) has been working with the DOE Morgantown Energy Technology Center to develop a new chemical monitor based on a unique sensor which responds selectively to vapors of chlorinated solvents. We are also developing field applications for the monitor in actual DOE cleanup operations. During the initial phase, prototype instruments were built and field tested. Because of the high degree of selectivity that is obtained, no response was observed with common hydrocarbon organic compounds such as BTX (benzene, toluene, xylene) or POLs (petroleum, oil, lubricants), and in fact, no non-halogen-containing chemical has been identified which induces a measurable response. By the end of the Phase I effort, a finished instrument system was developed and test marketed. This instrument, called the RCL MONITOR, was designed to analyze individual samples or monitor an area with automated repetitive analyses. Vapor levels between 0 and 500 ppm can be determined in 90 s with a lower detection limit of 0.2 ppm using the hand-portable instrument. In addition to the development of the RCL MONITOR, advanced sampler systems are being developed to: (1) extend the dynamic range of the instrument through autodilution of the vapor and (2) allow chemical analyses to be performed on aqueous samples. When interfaced to the samplers, the RCL MONITOR is capable of measuring chlorinated solvent contamination in the vapor phase up to 5000 ppm and in water and other condensed media from 10 to over 10,000 ppb(wt)--without hydrocarbon and other organic interferences.

Buttner, W.J.; Penrose, W.R.; Stetter, J.R.

1995-12-01

260

Screening of ground water samples for volatile organic compounds using a portable gas chromatograph  

Microsoft Academic Search

A portable gas chromatograph was used to screen 32 ground water samples for volatile organic compounds. Seven screened samples were positive; four of the seven samples had volatile organic substances identified by second-column confirmation. Four of the seven positive, screened samples also tested positive in laboratory analyses of duplicate samples. No volatile organic compounds were detected in laboratory analyses of

Buchmiller

2009-01-01

261

Normal Boiling Points for Organic Compounds: Correlation and Prediction by a Quantitative Structure-Property Relationship  

Microsoft Academic Search

We recently reported a successful correlation of the normal boiling points of 298 organic compounds containing O, N, Cl, and Br with two molecular descriptors.1 In the present study the applicability of these two descriptors for the prediction of boiling points for various other classes of organic compounds was investigated further by employing a diverse data set of 612 organic

Alan R. Katritzky; Victor S. Lobanov; Mati Karelson

1998-01-01

262

Occurrence of Pharmaceuticals, Hormones, and Organic Wastewater Compounds in Pennsylvania Waters, 2006-09.  

National Technical Information Service (NTIS)

Concern over the presence of contaminants of emerging concern, such as pharmaceutical compounds, hormones, and organic wastewater compounds (OWCs), in waters of the United States and elsewhere is growing. Laboratory techniques developed within the last de...

A. Proctor A. G. Reif C. A. Loper J. K. Crawford R. Manning R. Titler

2012-01-01

263

76 FR 41086 - Approval and Promulgation of Air Quality Implementation Plans; Ohio; Volatile Organic Compound...  

Federal Register 2010, 2011, 2012, 2013

...Volatile Organic Compound Reinforced Plastic Composites Production Operations Rule...compound (VOC) emissions from reinforced plastic composites production operations. This...applies to any facility that has reinforced plastic composites production operations....

2011-07-13

264

FACTORS CONTROLLING THE EMISSIONS OF MONOTERPENES AND OTHER VOLATILE ORGANIC COMPOUNDS  

EPA Science Inventory

Plants contain a number of volatile organic compounds, including isoprene, mono- and sesquiterpenes, alcohols, aldehydes, ketones, and esters. ndividual plant species have unique combinations of these compounds; consequently, the emission pattern for each species is also specific...

265

Tetratopic phenyl compounds, related metal-organic framework materials and post-assembly elaboration  

DOEpatents

Disclosed are tetratopic carboxylic acid phenyl for use in metal-organic framework compounds. These compounds are useful in catalysis, gas storage, sensing, biological imaging, drug delivery and gas adsorption separation.

Farha, Omar K; Hupp, Joseph T

2013-06-25

266

Solutions of Organic Compounds in Fused Alkali Thiocyanates.  

National Technical Information Service (NTIS)

High solubility of polyhydroxy compounds was observed in the fused salts of a mixture of the thiocyanates of potassium and sodium and of potassium thiocyanate alone. The hydroxy compounds are apparently unionized in solution, and the fused-salt solubility...

T. I. Crowell P. Hillery

1964-01-01

267

Predicting flammability of gas mixtures containing volatile organic compounds  

SciTech Connect

One requirement regarding the transportation of transuranic (TRU) radioactive waste containers currently limits the total concentration of potentially flammable volatile organic compounds (VOCs) and flammable gases in the headspace of the waste container. Typical VOCs observed in the drums include aromatic hydrocarbons, ketones, alcohols, cyclohexane, as well as chlorinated hydrocarbons (alkanes and alkenes). Flammable gases, such as hydrogen and methane, may be generated in the containers by radiation-induced decomposition (radiolysis) of water and hydrocarbon waste forms. An experimental program was initiated to identify an accurate means for predicting flammability for gas mixtures containing one or more of the following species: hydrogen, carbon tetrachloride, 1,2-dichloroethane, toluene, or 2-butanone. The lower flammability limits (LFL) of gas mixtures containing equimolar quantity for each species were determined in a 19-liter laboratory flammability chamber using a strong spark ignition source. The group factor contribution method was determined to be more accurate than the LeChatelier method for estimating the LFL for these gas mixtures.

Liekhus, K. [Lockheed Martin Idaho Technologies Co., Idaho Falls, ID (United States). Idaho National Engineering and Environmental Lab.; Zlochower, I. [National Inst. for Occupational Safety and Health, Pittsburgh, PA (United States). Pittsburgh Research Lab.; Djordjevic, S.; Loehr, C. [Benchmark Environmental, Albuquerque, NM (United States)

1997-12-31

268

Identification of nonmethane organic compound emissions from grassland vegetation.  

SciTech Connect

Emissions of nonmethane organic compounds (NMOCs) from grassland vegetation were collected in Summa(reg.sign) passivated stainless-steel canisters with a static enclosure technique and were analyzed by high-resolution gas chromatography with flame ionization and ion trap mass spectrometric detectors. Approximately 40 NMOCs with 6-10 carbon atoms were observed in samples analyzed by high-resolution gas chromatography with the flame ionization detector. Nineteen NMOCs in this molecular weight range (6 aliphatic oxygenates; 1 aromatic hydrocarbon; and 4 acyclic, 5 monocyclic, and 3 bicyclic monoterpenoids) were identified by ion trap mass spectrometry. Mass spectrometry was particularly useful for identifying myrcene and cis-3-hexenylacetate, which coeluted on a fused-silica capillary column coated with a 1-{mu}m-thick film of polydimethylsiloxane. An evaluation of the reactivity of the grassland emissions revealed that the aliphatic oxygenates have lifetimes of a few hours with respect to oxidation by OH and O{sub 3} in the atmosphere. This value is similar to the lifetimes of the bicyclic monoterpenoids. The expected lifetimes of the monoterpenoids with respect to oxidation by NO{sub 3} are only several minutes.

Fukui, Y.; Doskey, P. V.; Environmental Research; NASA Ames Research Center

2000-01-01

269

Analysis of volatile organic compounds released during food decaying processes.  

PubMed

A number of volatile organic compounds (VOCs) including acetone, methyl ethyl ketone, toluene, ethylbenzene, m,p-xylene, styrene, and o- xylene released during food decaying processes were measured from three types of decaying food samples (Kimchi (KC), fresh fish (FF), and salted fish (SF)). To begin with, all the food samples were contained in a 100-mL throwaway syringe. These samples were then analyzed sequentially for up to a 14-day period. The patterns of VOC release contrasted sharply between two types of fish (FF and SF) and KC samples. A comparison of data in terms of total VOC showed that the mean values for the two fish types were in the similar magnitude with 280 ± 579 (FF) and 504 ± 1,089 ppmC (SF), while that for KC was much lower with 16.4 ± 7.6 ppmC. There were strong variations in VOC emission patterns during the food decaying processes between fishes and KC that are characterized most sensitively by such component as styrene. The overall results of this study indicate that concentration levels of the VOCs differed significantly between the food types and with the extent of decaying levels through time. PMID:21541778

Phan, Nhu-Thuc; Kim, Ki-Hyun; Jeon, Eui-Chan; Kim, Uk-Hun; Sohn, Jong Ryeul; Pandey, Sudhir Kumar

2011-05-04

270

A biogenic volatile organic compounds emission inventory for Yunnan Province.  

PubMed

The first detailed inventory for volatile organic compounds (VOC) emissions from vegetation over Yunnan Province, China was presented. The spatially and temporally resolved inventory was developed based on a geographic information system (GIS), remote sensing (RS) data and field measurement data, such as digitized land-use data, normalized difference vegetation index (NDVI) and temperature data from direct real-time measurement. The inventory has a spatial resolution of 5 km x 5 km and a time resolution of 1 h. Urban, agriculture, and natural land-use distributions in Yunnan Province were combined with biomass factors for each land-use category to produce a spatially resolved biomass inventory. A biogenic emission inventory was developed by combining the biomass inventory with hourly emission rates for tree, shrub and ground cover species of the study area. Correcting for environmental factors, including light intensity and temperature, a value of 1.1 x 10(12) gC for total annual biogenic VOC emissions from Yunnan Province, including 6.1 x 10(11) gC for isoprene, 2.1 x 10(11) gC for monoterpenes, and 2.6 x 10(11) gC for OVOC was obtained. The highest VOC emissions occurred in the northwestern, southwestern and north region of Yunnan Province. Some uncertainties were also discussed in this study. PMID:16083102

Wang, Zhi-Hui; Bai, Yu-Hua; Zhang, Shu-Yu

2005-01-01

271

Prediction of boiling points of organic compounds by QSPR tools.  

PubMed

The novel electro-negativity topological descriptors of YC, WC were derived from molecular structure by equilibrium electro-negativity of atom and relative bond length of molecule. The quantitative structure-property relationships (QSPR) between descriptors of YC, WC as well as path number parameter P3 and the normal boiling points of 80 alkanes, 65 unsaturated hydrocarbons and 70 alcohols were obtained separately. The high-quality prediction models were evidenced by coefficient of determination (R(2)), the standard error (S), average absolute errors (AAE) and predictive parameters (Qext(2),RCV(2),Rm(2)). According to the regression equations, the influences of the length of carbon backbone, the size, the degree of branching of a molecule and the role of functional groups on the normal boiling point were analyzed. Comparison results with reference models demonstrated that novel topological descriptors based on the equilibrium electro-negativity of atom and the relative bond length were useful molecular descriptors for predicting the normal boiling points of organic compounds. PMID:23792208

Dai, Yi-Min; Zhu, Zhi-Ping; Cao, Zhong; Zhang, Yue-Fei; Zeng, Ju-Lan; Li, Xun

2013-05-04

272

Superconductivity in Organic Compounds with Pseudo-Triangular Lattice  

NASA Astrophysics Data System (ADS)

We study spin fluctuation (SF) mediated superconductivity (SC) in a half-filled square lattice Hubbard model with the transfer matrices -t between nearest neighbor sites and -t' between a half of next nearest neighbor sites neighboring along only one of the < 1,1 > directions, considering application of this model to organic ?-(BEDT-TTF)2 X compounds. Varying the t'/t value from 0 to 1, one can interpolate between a square and an equilateral triangular lattice, the latter giving frustration to antiferromagnetically (AF) coupled spin systems. Within the fluctuation exchange (FLEX) approximation, we calculate ?(q,?), Tc and the SC order parameter for various model parameter values and find that both AF and SC are suppressed as one approaches the frustration geometry or |(t'/t)-1| \\to 0. The SC phase, however, extends beyond the AF phase boundary fairly close to t'/t = 1 for realistic U/t values. The order parameter is of x^2-y2-type for t'/t < 1 and of xy-type for t'/t > 1.

Kondo, Hisashi; Moriya, Tôru

2004-04-01

273

Predicting the emission rate of volatile organic compounds fromvinyl flooring  

SciTech Connect

A model for predicting the rate at which a volatile organic compound (VOC) is emitted from a diffusion-controlled material is validated for three contaminants (n-pentadecane, n-tetradecane, and phenol) found in vinyl flooring (VF). Model parameters are the initial VOC concentration in the material-phase (C{sub 0}), the material/air partition coefficient (K), and the material-phase diffusion coefficient (D). The model was verified by comparing predicted gas-phase concentrations to data obtained during small-scale chamber tests, and by comparing predicted material-phase concentrations to those measured at the conclusion of the chamber tests. Chamber tests were conducted with the VF placed top side up and bottom side up. With the exception of phenol, and within the limits of experimental precision, the mass of VOCs recovered in the gas phase balances the mass emitted from the material phase. The model parameters (C{sub 0}, K, and D) were measured using procedures that were completely independent of the chamber test. Gas- and material-phase predictions compare well to the bottom-side-up chamber data. The lower emission rates for the top-side-up orientation may be explained by the presence of a low-permeability surface layer. The sink effect of the stainless steel chamber surface was shown to be negligible.

Cox, Steven S.; Little, John C.; Hodgson, Alfred T.

2001-03-01

274

[Volatile organic compounds (VOCs) emitted from large furniture].  

PubMed

Indoor air pollution by volatile organic compounds (VOCs), which may cause a hazardous influence on human being such as sick building (sick house) syndrome, has become a serious problem. In this study, VOCs emitted from nine pieces of home furniture, three sets of dining tables, three sets of chest of drawers and three sofas, were analyzed as potential sources of indoor air pollution by large chamber test method (JIS A 1911). Based on the emission rates of total VOC (TVOC), the impacts on the indoor TVOC was estimated by the sample model with a volume of 20 m3 and ventilation frequency of 0.5 times/h. The estimated TVOC increment values were exceeded the provisional target value for indoor air (400 microg/m3) in three sets of dining tables, one set of chest of drawer and one sofa. The estimated increment of formaldehyde were exceeded the guideline value (100 microg/m3) in one set of dining table, two sets of chest of drawers and one sofa. These results revealed that VOC emissions from furniture may influence significantly indoor air quality. Also, in this study, to establish the alternative method for large chamber test methods, emission rates from representative three parts of furniture unit were evaluated using the small chamber and emission rate from full-sized furniture was predicted. Emission rates of TVOC and formaldehyde predicted by small chamber test were 3-46% and 6-252% of the data obtained using large chamber test, respectively. PMID:22259846

Tanaka-Kagawa, Toshiko; Furuta, Mitsuko; Shibatsuji, Masayoshi; Jinno, Hideto; Nishimura, Tetsuji

2011-01-01

275

Advanced heat pump for the recovery of volatile organic compounds  

SciTech Connect

Emissions of Volatile Organic Compounds (VOC) from stationary industrial and commercial sources represent a substantial portion of the total US VOC emissions. The Toxic-Release Inventory'' of The US Environmental Protection Agency estimates this to be at about 3 billion pounds per year (1987 estimates). The majority of these VOC emissions are from coating processes, cleaning processes, polymer production, fuel production and distribution, foam blowing,refrigerant production, and wood products production. The US Department of Energy's (DOE) interest in the recovery of VOC stems from the energy embodied in the recovered solvents and the energy required to dispose of them in an environmentally acceptable manner. This Phase I report documents 3M's work in close working relationship with its subcontractor Nuclear Consulting Services (Nucon) for the preliminary conceptual design of an advanced Brayton cycle heat pump for the recovery of VOC. Nucon designed Brayton cycle heat pump for the recovery of methyl ethyl ketone and toluene from coating operations at 3M Weatherford, OK, was used as a base line for the work under cooperative agreement between 3M and ODE. See appendix A and reference (4) by Kovach of Nucon. This cooperative agreement report evaluates and compares an advanced Brayton cycle heat pump for solvent recovery with other competing technologies for solvent recovery and reuse. This advanced Brayton cycle heat pump is simple (very few components), highly reliable (off the shelf components), energy efficient and economically priced.

Not Available

1992-03-01

276

Screening of ground water samples for volatile organic compounds using a portable gas chromatograph  

USGS Publications Warehouse

A portable gas chromatograph was used to screen 32 ground water samples for volatile organic compounds. Seven screened samples were positive; four of the seven samples had volatile organic substances identified by second-column confirmation. Four of the seven positive, screened samples also tested positive in laboratory analyses of duplicate samples. No volatile organic compounds were detected in laboratory analyses of samples that headspace screening indicated to be negative. Samples that contained volatile organic compounds, as identified by laboratory analysis, and that contained a volatile organic compound present in a standard of selected compounds were correctly identified by using the portable gas chromatography. Comparisons of screened-sample data with laboratory data indicate the ability to detect selected volatile organic compounds at concentrations of about 1 microgram per liter in the headspace of water samples by use of a portable gas chromatography. -Author

Buchmiller, R. C.

1989-01-01

277

Syntheses, characterizations and properties of organic-inorganic perovskite compounds  

NASA Astrophysics Data System (ADS)

The purpose of this work is to synthesize and characterize a family of organic-based tin(II) iodide layered perovskites---[H3N(CH 2)mNH3](CH3NH 3)n-1SnnI 3n+1 (n = 1--4, m = 4--6, 7, 8, 9, 12). The crystalline hybrid compounds were prepared by crystallization from acidic HI solutions (Method I) and by gel techniques (Method II). The crystal structures of the resulting products were characterized by single crystal X-ray diffraction and IR spectroscopy. Their electronic structure and chemical bonding were investigated by UV-VIS reflectance spectroscopy, 4-probe resistivity measurements, and electronic band structure calculations. Normal flat single-layered perovskites with a variety of alkyldiamines---[H 3N(CH2)mNH3]SnI 4 (m = 4--6, 8, 9), were obtained from Method I, while those with longer hydrocarbon chains, e.g. [H3N(CH2)12NH 3]SnI4, were synthesized by Method II. The typical unit cell of these compounds consist of a 2-dimensional inorganic anion [SnI4 2-]---mono-layered perovskite sheets, and layers of [H 3N(CH2)mNH3] 2+ cations packed between the inorganic sheets. An unexpected corrugated anion sheet, [SnI4]2-, was also observed, for the first time, in alpha-[H3N(CH2)SNH3]SnI 4. The multi-layered perovskite hybrid compounds---the double-layered [H3N(CH2)SNH3](CH3NH3)SnI 7, the triple-layered perovskites [H3N(CH 2)4NH3](CH3NH3)2Sn 3I10, and [H3N(CH2)6NH 3](CH3NH3)2Sn3I10, and a quadruple-layered [H3N(CH2)SNH3](CH 3NH3)3Sn4I13 were obtained in polycrystalline and single crystalline forms. Single crystal X-ray diffraction, electronic band structure calculations, and electronic resistivity measurements were performed on representative members of the family of hybrid perovskites. Attempts to introduce nonprimary amines into the layered perovskite structures resulted in the preparation of 2,2'-biimidazolium tin iodide---[NH(CH)2NHC]2SnI4 and morpholinium tin iodide[O(CH2)2NH2(CH2) 2]2SnI4. These are the first reports of nonprimary amine-based layered perovskite structures. Their crystal structures reveal significant deviations from typical layered perovskite structures, characterized by severely distorted SnI6 octahedral units. Electronic band structure calculations, using the tight-binding approach, reveal significant interplay of the stereoactivity of the Sn(II) lone-pairs with the onset of hypervalent secondary bonding in morpholinium tin iodide. Thus, the seemingly layered perovskite structure of morpholinium tin iodide exhibits a one-dimensional bonding character. Two unprecedented three-dimensional (3-D) defect perovskite compounds, [H3N(CH2)7NH3]2Sn 3I10 and [H3N(CH2)7NH 3]8(H3NCH3)2Sn(IV)Sn(II) 12I46 were prepared. Their novel 3-D structures can be derived from the ordered arrangement of vacancies on the metal and anion sites of the perovskite. These defect perovskite structures are unique to metal oxide and halide chemistry.

Guan, Jun

2001-12-01

278

A review of the tissue residue approach for organic and organometallic compounds in aquatic organisms.  

PubMed

This paper reviews the tissue residue approach (TRA) for toxicity assessment as it applies to organic chemicals and some organometallic compounds (Sn, Hg, and Pb) in aquatic organisms. Specific emphasis was placed on evaluating key factors that influence interpretation of critical body residue (CBR) toxicity metrics including data quality issues, lipid dynamics, choice of endpoints, processes that alter toxicokinetics and toxicodynamics, phototoxicity, species- and life stage-specific sensitivities, and biotransformation. The vast majority of data available on TRA is derived from laboratory studies of acute lethal responses to organic toxicants exhibiting baseline toxicity. Application of the TRA to various baseline toxicants as well as substances with specific modes of action via receptor-mediated processes, such as chlorinated aromatic hydrocarbons, pesticides, and organometallics is discussed, as is application of TRA concepts in field assessments of tissue residues. In contrast to media-based toxicity relationships, CBR values tend to be less variable and less influenced by factors that control bioavailability and bioaccumulation, and TRA can be used to infer mechanisms of toxic action, evaluate the toxicity of mixtures, and interpret field data on bioaccumulated toxicants. If residue-effects data are not available, body residues can be estimated, as has been done using the target lipid model for baseline toxicants, to derive critical values for risk assessment. One of the primary unresolved issues complicating TRA for organic chemicals is biotransformation. Further work on the influence of biotransformation, a better understanding of contaminant lipid interactions, and an explicit understanding of the time dependency of CBRs and receptor-mediated toxicity are all required to advance this field. Additional residue-effects data on sublethal endpoints, early life stages, and a wider range of legacy and emergent contaminants will be needed to improve the ability to use TRA for organic and organometallic compounds. PMID:21184569

McElroy, Anne E; Barron, Mace G; Beckvar, Nancy; Driscoll, Susan B Kane; Meador, James P; Parkerton, Tom F; Preuss, Thomas G; Steevens, Jeffery A

2010-12-09

279

Source apportionment modeling of volatile organic compounds in streams.  

PubMed

It often is of interest to understand the relative importance of the different sources contributing to the concentration c(w) of a contaminant in a stream; the portions related to sources 1, 2, 3, etc. are denoted c(w,1), c(w2), c(w3), etc. Like c(w), the fractions alpha1 = c(w,1)/c(w), alpha2 = c(w,2)/c(w), alpha3 = c(w,3)/c(w), etc. depend on location and time. Volatile organic compounds (VOCs) can undergo absorption from the atmosphere into stream water or loss from stream water to the atmosphere, causing complexities affecting the source apportionment (SA) of VOCs in streams. Two SA rules are elaborated. Rule 1: VOC entering a stream across the air/water interface exclusively is assigned to the atmospheric portion of c(w). Rule 2: VOC loss by volatilization, flow loss to groundwater, in-stream degradation, etc. is distributed over c(w,1), c(w,2), c(w3), etc. in proportion to their corresponding alpha values. How the two SA rules are applied, as well as the nature of the SA output for a given case, will depend on whether transport across the air/water interface is handled using the net flux F convention or using the individual fluxes J convention. Four hypothetical stream cases involving acetone, methyl-tert-butyl ether (MTBE), benzene, chloroform, and perchloroethylene (PCE) are considered. Acetone and MTBE are sufficiently water soluble from air for a domestic atmospheric source to be capable of yielding c(w) values approaching the common water quality guideline range of 1 to 10 microg/L. For most other VOCs, such levels cause net outgassing (F > 0). When F > 0 in a given section of stream, in the net flux convention, all of the alpha(j) for the compound remain unchanged over that section while c(w) decreases. A characteristic time tau(d) can be calculated to predict when there will be differences between SA results obtained by the net flux convention versus the individual fluxes convention. Source apportionment modeling provides the framework necessary for comparing different strategies for mitigating contamination at points of interest along a stream. PMID:16629131

Pankow, James F; Asher, William E; Zogorski, John S

2006-04-01

280

Precipitate hydrolysis process for the removal of organic compounds from nuclear waste slurries  

DOEpatents

A process for removing organic compounds from a nuclear waste slurry comprising reacting a mixture of radioactive waste precipitate slurry and an acid in the presence of a catalytically effective amount of a copper (II) catalyst whereby the organic compounds in the precipitate slurry are hydrolyzed to form volatile organic compounds which are separated from the reacting mixture. The resulting waste slurry, containing less than 10 percent of the orginal organic compounds, is subsequently blended with high level radioactive sludge and transferred to a virtrification facility for processing into borosilicate glass for long-term storage.

Doherty, Joseph P. (Elkton, MD); Marek, James C. (Augusta, GA)

1989-01-01

281

Survival of Organic Compounds on Al Foil Under Stardust Conditions  

NASA Astrophysics Data System (ADS)

Organic material was captured on the Al foils of the Stardust collector. We studied the survival of organic material under Stardust conditions to understand the processing that organic crater residues, found on the flight foils, must have undergone.

Henkel, T.; Lyon, I. C.; Kearsley, A. T.; Price, M. C.; Cole, M. J.; Burchell, M.

2012-03-01

282

Adsorption of volatile organic compounds in porous metal-organic frameworks functionalized by polyoxometalates  

NASA Astrophysics Data System (ADS)

The functionalization of porous metal-organic frameworks (Cu3(BTC)2) was achieved by incorporating Keggin-type polyoxometalates (POMs), and further optimized via alkali metal ion-exchange. In addition to thermal gravimetric analysis, IR, single-crystal X-ray diffraction, and powder X-ray diffraction, the adsorption properties were characterized by N2 and volatile organic compounds (VOCs) adsorption measurements, including short-chain alcohols (C<4), cyclohexane, benzene, and toluene. The adsorption enthalpies estimated by the modified Clausius-Clapeyron equation provided insight into the impact of POMs and alkali metal cations on the adsorption of VOCs. The introduction of POMs not only improved the stability, but also brought the increase of adsorption capacity by strengthening the interaction with gas molecules. Furthermore, the exchanged alkali metal cations acted as active sites to interact with adsorbates and enhanced the adsorption of VOCs.

Ma, Feng-Ji; Liu, Shu-Xia; Liang, Da-Dong; Ren, Guo-Jian; Wei, Feng; Chen, Ya-Guang; Su, Zhong-Min

2011-11-01

283

Mass transfer of nonvolatile organic compounds from porous media  

NASA Astrophysics Data System (ADS)

This thesis presents data pertaining to the mass transfer of nonvolatile organic compounds from porous media. Physical properties of porous solids, including surface and pore areas, are studied. Information from these studies, along with dissolution data, are used to develop correlations relating the Sherwood Number to the Peclet Number. The contaminant used in this study is naphthalene; the solids used are Moffett Sand (MS), Borden Sand (BS), Lampblack (LB), and Silica Gel (SG). Surface area results indicate that contamination at 0.1% reduces the area of MS and SG by 48 and 37%, respectively, while contamination at 1.0% reduces the area of MS, BS, and SG by 59, 56, and 40%, respectively. Most of the reduction in area originates in the reduction of pore areas and volumes, where the contaminant precipitates. After long-term storage, surface areas did not recover to their original values due to an "irreversible" fraction of naphthalene. Treatment with heat or solvent or both was necessary to completely remove the contamination. For lampblack, treatment at 100°C decreased areas while treatment at 250°C increased them. Treatment at 250°°C probably opened pores while that at 100°C may have blocked more pores by redistributing the tar-like contaminant characteristic of lampblack. Contaminated MS and SG solids are packed in columns through which water is pumped. The effluent began at a relatively high concentration (˜70% of solubility) for both samples. However, SG column concentrations dropped quickly, never achieving steady state while the MS samples declined more gradually towards steady state. The high pore areas of the SG samples are believed to cause this behavior. The steady state portion of the MS dissolution history is used to develop mass transfer correlations. The correlation in this study differs from previous work in two major ways: (1) the exponent on the Pe is three times larger and (2) the limiting Sh is 106 times smaller. These results suggest that the dissolution mechanism here is different than in other studies, that is, dissolution is occurring from the contaminated pores which are inaccessible to the flowing water. This work can be used to assess the leaching potential of non-volatile organic impacted soils. Also, soil vapor extraction schemes which are hampered by observed long tails can be explained using the data in this thesis.

Khachikian, Crist Simon

284

Presence and Distribution of Organic Wastewater Compounds in Wastewater, Surface, Ground, and Drinking Waters, Minnesota, 2000-02.  

National Technical Information Service (NTIS)

Household, industrial, and agricultural-use com-pounds (HIAs), pharmaceuticals, antibiotics, sterols, and hormones are newly recognized classes of organic com-pounds that are often associated with wastewater. These organic wastewater compounds (OWCs) are ...

K. E. Lee L. B. Barber E. T. Furlong J. D. Cahill D. W. Kolpin M. T. Meyer S. D. Zaugg

2004-01-01

285

Volatile organic compound emissions from dry mill fuel ethanol production.  

PubMed

Ethanol fuel production is growing rapidly in the rural Midwest, and this growth presents potential environmental impacts. In 2002, the U.S. Environmental Protection Agency (EPA) and the Minnesota Pollution Control Agency (MPCA) entered into enforcement actions with 12 fuel ethanol plants in Minnesota. The enforcement actions uncovered underreported emissions and resulted in consent decrees that required pollution control equipment be installed. A key component of the consent decrees was a requirement to conduct emissions tests for volatile organic compounds (VOCs) with the goal of improving the characterization and control of emissions. The conventional VOC stack test method was thought to underquantify total VOC emissions from ethanol plants. A hybrid test method was also developed that involved quantification of individual VOC species. The resulting database of total and speciated VOC emissions from 10 fuel ethanol plants is relatively small, but it is the most extensive to date and has been used to develop and gauge compliance with permit limits and to estimate health risks in Minnesota. Emissions were highly variable among facilities and emissions units. In addition to the variability, the small number of samples and the presence of many values below detection limits complicate the analysis of the data. To account for these issues, a nested bootstrap procedure on the Kaplan-Meier method was used to calculate means and upper confidence limits. In general, the fermentation scrubbers and fluid bed coolers emitted the largest mass of VOC emissions. Across most facilities and emissions units ethanol was the pollutant emitted at the highest rate. Acetaldehyde, acetic acid, and ethyl acetate were also important emissions from some units. Emissions of total VOCs, ethanol, and some other species appeared to be a function of the beer feed rate, although the relationship was not reliable enough to develop a production rate-based emissions factor. PMID:17912928

Brady, Daniel; Pratt, Gregory C

2007-09-01

286

A biogenic volatile organic compounds emission inventory for Beijing  

NASA Astrophysics Data System (ADS)

The present study presents us the first detailed inventory for volatile organic compounds (VOC) emissions from vegetation over Beijing, China. The spatially and temporally resolved inventory was developed based on a Geographic Information system (GIS), Remote sensing (RS) data and field measurement data, such as digitized land-use data, normalized difference vegetation index (NDVI) and temperature and photosynthetic active radiation (PAR) data from direct real-time measurement. The inventory has a spatial resolution of 1×1 km2 and a time resolution of 1 h. Urban, agriculture, and natural land-use distributions in Beijing were combined with biomass factors for each land-use category to produce a spatially resolved biomass inventory. A biogenic emission inventory was developed by combining the biomass inventory with hourly emission rates for tree, shrub, and ground cover species of the study area. Twenty-three kinds of the emission rate data of the 39 vegetation types in Beijing were identified using a bag-enclosure sampling method followed by GC-FID analysis in our field measurement. Other emission rate data were quoted from previous study or assigned with the taxonomic method. Correcting for environmental factors, including light intensity and temperature, we arrive a value of 1.6×10 10 g C for total annual biogenic VOC emissions from Beijing, including 7.9×10 9 g C for isoprene, 3.5×10 9 g C for monoterpenes, and 4.8×10 9 g C for OVOC. Some uncertainties are also discussed in this study.

Zhihui, Wang; Yuhua, Bai; Shuyu, Zhang

287

[Ru/AC catalyzed ozonation of recalcitrant organic compounds].  

PubMed

Ozonation and Ru/AC catalyzed ozonation of dimethyl phthalate (DMP), phenols and disinfection by-products precursors were studied. It shows that Ru/AC catalyst can obviously enhance the mineralization of organic compounds. In the degradation of DMP, TOC removal was 28.84% by ozonation alone while it was 66.13% by catalytic ozonation. In the oxidation of 23 kinds of phenols, TOC removals were 9.57%-56.08% by ozonation alone while they were 41.81%-82.32% by catalytic ozonation. Compared to ozonation alone, Ru/AC catalyzed ozonation was more effective for the reduction of disinfection by-products formation potentials in source water. The reduction of haloacetic acids formation potentials was more obvious than thichlomethane formation potentials. After the treatment by catalytic ozonation, the haloacetic acids formation potentials decreased from 144.02 microg/L to 58.50 microg/L, which was below the standard value of EPA. However ozonation alone could not make it reach the standard. The treatments of source water by BAC, O3 + BAC, O3/AC + BAC and Ru/AC + O3 + BAC were also studied. In the four processes, TOC removal was 3.80%, 20.14%, 27.45% and 48.30% respectively, COD removal was 4.37%, 27.22%, 39.91% and 50.00% respectively, UV254 removal was 8.16%, 62.24%, 67.03% and 84.95% respectively. Ru/AC + O3 + BAC process is more effective than the other processes for the removal of TOC, COD and UV254 and no ruthenium leaching observed in the solution. It is a promising process for the treatment of micro polluted source water. PMID:19927805

Wang, Jian-Bing; Hou, Shao-Pei; Zhou, Yun-Rui; Zhu, Wan-Peng; He, Xu-Wen

2009-09-15

288

Speciation of Trace Organic Ligands and Inorganic and Organometallic Compounds in Oil Shale Process Waters.  

National Technical Information Service (NTIS)

The isolation and identification of organic ligands and inorganic and organometallic compounds in seven oil shale process waters has been carried out using a number of analytical techniques. Organic ligands, potentially associated with trace metals in the...

R. H. Fish

1980-01-01

289

Emission of volatile organic compounds from silage: Compounds, sources, and implications  

NASA Astrophysics Data System (ADS)

Silage, fermented cattle feed, has recently been identified as a significant source of volatile organic compounds (VOCs) to the atmosphere. A small number of studies have measured VOC emission from silage, but not enough is known about the processes involved to accurately quantify emission rates and identify practices that could reduce emissions. Through a literature review, we have focused on identifying the most important compounds emitted from corn silage (the most common type of silage in the US) and the sources of these compounds by quantifying their production and emission potential in silage and describing production pathways.We reviewed measurements of VOC emission from silage and assessed the importance of individual silage VOCs through a quantitative analysis of VOC concentrations within silage. Measurements of VOC emission from silage and VOCs present within silage indicated that alcohols generally make the largest contribution to emission from corn silage, in terms of mass emitted and potential ozone formation. Ethanol is the dominant alcohol in corn silage; excluding acids, it makes up more than half of the mean mass of VOCs present. Acids, primarily acetic acid, may be important when emission is high and all VOCs are nearly depleted by emission. Aldehydes and esters, which are more volatile than acids and alcohols, are important when exposure is short, limiting emission of more abundant but less volatile compounds.Variability in silage VOC concentrations is very high; for most alcohols and acids, tolerance intervals indicate that 25% of silages have concentrations a factor of two away from median values, and possibly much further. This observation suggests that management practices can significantly influence VOC concentrations. Variability also makes prediction of emissions difficult.The most important acids, alcohols, and aldehydes present in silage are probably produced by bacteria (and, in the case of ethanol, yeasts) during fermentation and storage of silage. Aldehydes may also be produced aerobically by spoilage microorganisms through the oxidation of alcohols. Abiotic reactions may be important for production of methanol and esters. Although silage additives appear to affect VOC production in individual studies, bacterial inoculants have not shown a consistent effect on ethanol, and effects on other VOCs have not been studied. Production of acetic acid is understood, and production could be minimized, but a decrease could lead to an increase in other, more volatile and more reactive, VOCs. Chemical additives designed for controlling yeasts and undesirable bacteria show promise for reducing ethanol production in corn silage.More work is needed to understand silage VOC production and emission from silage, including: additional measurements of VOC concentrations or production in silage of all types, and an exploration of the causes of variability; accurate on-farm measurements of VOC emission, including an assessment of the importance of individual ensiling stages and practices that could reduce emission of existing VOCs; and work on understanding the sources of silage VOCs and possible approaches for reducing production.

Hafner, Sasha D.; Howard, Cody; Muck, Richard E.; Franco, Roberta B.; Montes, Felipe; Green, Peter G.; Mitloehner, Frank; Trabue, Steven L.; Rotz, C. Alan

2013-10-01

290

Prevention of marine biofouling using natural compounds from marine organisms  

Microsoft Academic Search

All surfaces that are submerged in the sea rapidly become covered by a biofilm. This process, called biofouling, has substantial economic consequences. Paints containing tri-butyl-tin (TBT) and copper compounds are used to protect marine structures by reducing biofouling. However, these compounds have damaging effects on the marine environment, as they are not biodegradable. It has been noted that many seaweeds

Evelyn Armstrong; Kenneth G. Boyd; J. Grant Burgess

2000-01-01

291

Raman and fluorescence spectra of fluoro-organic compounds  

Microsoft Academic Search

The results of Raman and fluorescence spectra investigations of fluoroorganic aromatic compounds are presented. We present technique for realizing of qualitative and quantitative analysis of fluoroorganic aromatic compounds on the base of Raman and fluorescence spectroscopy. We propose to applicate the pulsed copper vapor laser for exciting of Raman and fluorescence spectra of fluoroorganic samples. The Raman spectra have been

Vladimir S. Gorelik; A. V. Chervyakov; L. I. Zlobina; Olga N. Sharts

1999-01-01

292

Speciation of volatile organic compound emissions for regional air quality modeling of particulate matter and ozone  

NASA Astrophysics Data System (ADS)

A new classification scheme for the speciation of organic compound emissions for use in air quality models is described. The scheme uses 81 organic compound classes to preserve both net gas-phase reactivity and particulate matter (PM) formation potential. Chemical structure, vapor pressure, hydroxyl radical (OH) reactivity, freezing point/boiling point, and solubility data were used to create the 81 compound classes. Volatile, semivolatile, and nonvolatile organic compounds are included. The new classification scheme has been used in conjunction with the Canadian Emissions Processing System (CEPS) to process 1990 gas-phase and particle-phase organic compound emissions data for summer and winter conditions for a domain covering much of eastern North America. A simple postprocessing model was used to analyze the speciated organic emissions in terms of both gas-phase reactivity and potential to form organic PM. Previously unresolved compound classes that may have a significant impact on ozone formation include biogenic high-reactivity esters and internal C6-8 alkene-alcohols and anthropogenic ethanol and propanol. Organic radical production associated with anthropogenic organic compound emissions may be 1 or more orders of magnitude more important than biogenic-associated production in northern United States and Canadian cities, and a factor of 3 more important in southern U.S. cities. Previously unresolved organic compound classes such as low vapour pressure PAHs, anthropogenic diacids, dialkyl phthalates, and high carbon number alkanes may have a significant impact on organic particle formation. Primary organic particles (poorly characterized in national emissions databases) dominate total organic particle concentrations, followed by secondary formation and primary gas-particle partitioning. The influence of the assumed initial aerosol water concentration on subsequent thermodynamic calculations suggests that hydrophobic and hydrophilic compounds may form external mixtures, and that separate treatment for these groups may be required in future air quality model simulations. The post-processing model used here overestimates the organic particle formation relative to measurements, lacks the complexity of a regional air quality model, and is not intended as an alternative to the latter. Results from the post-processing model do, however, provide guidance for the treatment of organic gases and particles in future air quality modeling work. Future air quality model simulations should attempt to speciate primary particulate organic compounds and include more detailed organic compound classes. Future emissions profile measurements should speciate gaseous high-molecular-mass organic compounds and primary organics emitted in particulate form (primary particle emissions are only available as a total particulate mass in currently available emissions data).

Makar, P. A.; Moran, M. D.; Scholtz, M. T.; Taylor, A.

2003-01-01

293

QSAR Modeling of Genotoxicity on Non-congeneric Sets of Organic Compounds  

Microsoft Academic Search

A multi-linear (ML) and artificial neural network (ANN) approaches have been used to derive quantitativestructure-activity relationships (QSAR) between the genotoxicity (mutagenicity) and molecular structure of compounds by using large initial pools of descriptors. All derived models involve descriptors that describe possible structural factors influencing the mutagenicbehavior of organic compounds. Different quantum chemical characteristics of compounds have been successfully used together

Uko Maran; Sulev Sild

2003-01-01

294

Xenobiotic organic compounds in leachates from ten Danish MSW landfills—chemical analysis and toxicity tests  

Microsoft Academic Search

A monitoring program comprising chemical analysis and biological toxicity testing of leachate samples from 10 Danish landfills (six engineered and four uncontrolled) revealed the presence of 55 different xenobiotic organic compounds (XOCs) and 10 degradation products of XOCs. The compounds belong to the following groups: BTEX, C3-benzenes, bicyclo compounds, napthalenes, chlorinated aliphatics, phenols (chloro-, methyl-, dimethyl, nonyl-), pesticides, and phthalates.

A. Baun; A. Ledin; L. A. Reitzel; P. L. Bjerg; T. H. Christensen

2004-01-01

295

Chlorinated and brominated persistent organic compounds in biological samples from the environment  

Microsoft Academic Search

Eleven selected biological samples representing different ecosystems, trophic levels, and areas mainly in Sweden have been analyzed for 31 halogenated organic compounds or compound groups. The multiresidue analytical method provides a good opportunity to compare the concentrations of the different compounds in the investigated samples. By the use of ratios of these concentrations, comparisons can be done between species and

Bo Jansson; Renate Andersson; Lillemor Asplund; K. Litzen; Kerstin Nylund; U. Sellstroem; Ulla-Britt Uvemo; Cajsa Wahlberg; Ulla Wideqvist; T. Odsjoe; Mats Olsson

1993-01-01

296

Rejection of organic micropollutants (disinfection by-products, endocrine disrupting compounds, and pharmaceutically active compounds) by NF\\/RO membranes  

Microsoft Academic Search

The growing demand on water resources has increased interest in wastewater reclamation for potable reuse, in which rejection of organic micropollutants such as disinfection by-products (DBPs), endocrine disrupting compounds (EDCs), and pharmaceutically active compounds (PhACs) is of great concern. The objective of this study was to investigate the rejection of DBPs, EDCs, and PhACs by nanofiltration (NF) and reverse osmosis

Katsuki Kimura; Gary Amy; Jörg E. Drewes; Thomas Heberer; Tae-Uk Kim; Yoshimasa Watanabe

2003-01-01

297

[Assessment of the emission of volatile organic compounds from polyurethane foams].  

PubMed

The emission of 2,4- and 2,6-diaminotoluene, triethylenediamine, diethanolamine and other volatile organic compounds from polyurethane foams was examined in environmental chamber. Tested materials did not release of amines. The emission of total volatile organic compounds showed differences for polyurethane samples but did not exceed ecological standards. PMID:15493351

Pecka, Irena; Wiglusz, Renata; Sitko, Elzbieta; Nikel, Grazyna

2004-01-01

298

40 CFR 60.112 - Standard for volatile organic compounds (VOC).  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standard for volatile organic compounds (VOC). 60.112 Section 60.112 Protection...Prior to May 19, 1978 § 60.112 Standard for volatile organic compounds (VOC). (a) The owner or operator of...

2013-07-01

299

40 CFR 60.312 - Standard for volatile organic compounds (VOC).  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standard for volatile organic compounds (VOC). 60.312 Section 60.312 Protection...Coating of Metal Furniture § 60.312 Standard for volatile organic compounds (VOC). (a) On and after the date on...

2013-07-01

300

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

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Alternate standard for volatile organic compounds. 60.542a Section 60.542a Protection of...Manufacturing Industry § 60.542a Alternate standard for volatile organic compounds. (a) On and after the date on which...

2013-07-01

301

40 CFR 60.112a - Standard for volatile organic compounds (VOC).  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Standard for volatile organic compounds (VOC). 60.112a Section 60.112a Protection...Prior to July 23, 1984 § 60.112a Standard for volatile organic compounds (VOC). (a) The owner or operator of...

2013-07-01

302

THE UTILIZATION OF ORGANIC COMPOUNDS AS MODERATORS AND COOLANTS IN NUCLEAR REACTORS. SUMMARY REPORT  

Microsoft Academic Search

In the last few years investigattons made on organic compounds have ; established the suitability of polyphenyls as reactor moderators and coolants. ; The introduction of these materials necessitates an accurate knowledge of the ; behavior of organic compounds under irradiation. The present report gives a ; survey on the principal results of works published up to the present. The

Starke

1961-01-01

303

Remotion of organic compounds of actual industrial effluents by electron beam irradiation  

Microsoft Academic Search

Organic compounds has been a great problem of environmental pollution, the traditional methods are not efficient on removing these compounds and most of them are deposited to ambient and stay there for long time causing problems to the environment. Ionizing radiation has been used with success to destroy organic molecules. Actual industrial effluents were irradiated using IPEN's electron beam wastewater

M. H. O. Sampa; C. L. Duarte; P. R. Rela; E. S. R. Somessari; C. G. Silveira; A. L. Azevedo

1998-01-01

304

Remotion of organic compounds of actual industrial effluents by electron beam irradiation  

Microsoft Academic Search

Organic compounds has been a great problem of environmental pollution, the traditional methods are not effecient on removing these compounds and most of them are deposited to ambient and stay there for long time causing problems to the environment. Ionizing radiation has been used with success to destroy organic molecules. Actual industrial effluents were irradiated using IPEN's electron beam wastewater

M. H. O. Sampa; C. L. Duarte; P. R. Rela; E. S. R. Somessari; C. G. Silveira; A. L. Azevedo

1998-01-01

305

The effect of concentration polarization on the separation of volatile organic compounds from water by pervaporation  

Microsoft Academic Search

Concentration polarization dominates the separation of dissolved volatile organic compounds from water by pervaporation. This is particularly true with hydrophobic organics, such as toluene and trichloroethylene, for which concentration polarization is severe even in highly turbulent membrane modules. With these compounds, measured separation factors can be 10 to 20% of the intrinsic separation factors in the absence of concentration polarization.

R. W. Baker; J. G. Wijmans; A. L. Athayde; R. Daniels; J. H. Ly; M. Le

1997-01-01

306

Quantitative Analysis of Organic Compounds: A Simple and Rapid Method for Use in Schools  

ERIC Educational Resources Information Center

Describes the procedure for making a quantitative analysis of organic compounds suitable for secondary school chemistry classes. Using the Schoniger procedure, the organic compound, such as PVC, is decomposed in a conical flask with oxygen. The products are absorbed in a suitable liquid and analyzed by titration. (JR)

Schmidt, Hans-Jurgen

1973-01-01

307

Quantitative Analysis of Organic Compounds: A Simple and Rapid Method for Use in Schools  

ERIC Educational Resources Information Center

|Describes the procedure for making a quantitative analysis of organic compounds suitable for secondary school chemistry classes. Using the Schoniger procedure, the organic compound, such as PVC, is decomposed in a conical flask with oxygen. The products are absorbed in a suitable liquid and analyzed by titration. (JR)|

Schmidt, Hans-Jurgen

1973-01-01

308

Adsorption of organic compounds pertinent to urban environments onto mineral dust particles  

Microsoft Academic Search

The interaction of mineral dust particles from the Sahara with semivolatile organic compounds over an urban region in Israel's coastal plain was studied. Dust samples were collected during numerous dust storm events in 2000 and 2001, under varying meteorological conditions. Organic compounds adsorbed on collected mineral dust particles were analyzed using an integrated, multitechnique study that employed a scanning electron

Alla H. Falkovich; Gal Schkolnik; Eliezer Ganor; Yinon Rudich

2004-01-01

309

Study on the local atomic structure of germanium in organic germanium compounds by EXAFS  

NASA Astrophysics Data System (ADS)

Organic germanium compounds have been extensively applied in medicine as tonics. In this paper, the local structures of two organic germanium compounds, carboxyethylgermanium sesquioxide and polymeric germanium glutamate, were determined by EXAFS. The structure parameters including coordination numbers and bond lengths were reported, and possible structure patterns were discussed.

Wang, Yin; Wu, Zhong; Shi, Yun; Wang, Yong

1999-04-01

310

Photochemical ozone creation potentials for organic compounds in northwest Europe calculated with a master chemical mechanism  

Microsoft Academic Search

Master Chemical Mechanism containing over 2400 chemical species and over 7100 chemical reactions is employed here to describe the atmospheric degradation of 120 organic compounds and the associated regional scale ozone and PAN formation under conditions appropriate to the polluted boundary layer over northwest Europe. Photochemical ozone and PAN creation potentials (POCP and PPCP) are derived for each organic compound

Richard G. Derwent; Michael E. Jenkin; Sandra M. Saunders; Michael J. Pilling

1998-01-01

311

Chlorinated Volatile Organic Compounds—Old, However, Actual Analytical and Toxicological Problem  

Microsoft Academic Search

The interest in chlorinated volatile organic compounds is not a new task but still draws the attention of scientists. The role they play in human organism, is an important aspect to consider, since the development of analytical techniques and instrumental solutions gives new possibilities of their application in the analytics of volatile compounds and recognition of properties, so far impossible

El?bieta Dobrzy?ska; Ma?gorzata Po?niak; Ma?gorzata Szewczy?ska; Bogus?aw Buszewski

2010-01-01

312

Sorption of organic compounds in the aqueous phase onto tire rubber  

Microsoft Academic Search

Batch sorption tests were conducted to investigate the sorption capacity of organic compounds by ground tire and to assess the effects of the presence of other organic compounds, ionic strength, pH, ground tire particle size, and temperature on sorption. None of the factors were significant under the conditions tested, m-Xylene had the highest partition coefficient, followed by ethylbenzene, toluene, trichloroethylene,

Jae Y. Kim; Jae K. Park; Tuncer B. Edil

1997-01-01

313

Analysis of industrial contaminants in indoor air: part 1. Volatile organic compounds, carbonyl compounds, polycyclic aromatic hydrocarbons and polychlorinated biphenyls.  

PubMed

This article reviews recent literature on the analysis of industrial contaminants in indoor air in the framework of the REACH project, which is mainly intended to improve protection of human health and the environment from the risks of more than 34 millions of chemical substances. Industrial pollutants that can be found in indoor air may be of very different types and origin, belonging to the volatile organic compounds (VOCs) and semivolatile organic compounds (SVOCs) categories. Several compounds have been classified into the priority organic pollutants (POPs) class such as polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and furans (PCDD/PCDFs) and related polychlorinated compounds, and polycyclic aromatic hydrocarbons (PAHs). Many of these compounds are partially associated to the air gas phase, but also to the suspended particulate matter. Furthermore, settled dust can act as a concentrator for the less volatile pollutants and has become a matrix of great concern for indoors contamination. Main literature considered in this review are papers from the last 10 years reporting analytical developments and applications regarding VOCs, aldehydes and other carbonyls, PCBs, PCDDs, PCDFs, and PAHs in the indoor environment. Sample collection and pretreatment, analyte extraction, clean-up procedures, determination techniques, performance results, as well as compound concentrations in indoor samples, are summarized and discussed. Emergent contaminants and pesticides related to the industrial development that can be found in indoor air are reviewed in a second part in this volume. PMID:19019381

Barro, Ruth; Regueiro, Jorge; Llompart, María; Garcia-Jares, Carmen

2008-11-06

314

Natural sulphurization of ketones and aldehydes: A key reaction in the formation of organic sulphur compounds  

Microsoft Academic Search

Acids, ketones, aldehydes, and alcohols were tested in the laboratory as substrates for hydrosulphurization under mild conditions. Ketone and aldehyde model compounds (i.e., 2-nonanone, nonanal, cholestan-3-one and phytenal) formed significant amounts of organic sulphur compounds, in which the oxo group was substituted by a polysulphide moiety. These results are used to explain the formation of several organic sulphur compounds reported

Stefan Schouten; Giel B. van Driel; Jaap S. Sinninghe Damsté; Jan W. de Leeuw

1993-01-01

315

Reaction Rates of Semi-Volatile Organic Compounds with the Hydroxyl Radical  

Microsoft Academic Search

The atmosphere is the primary route of global dispersion of many semi-volatile organic compounds (SOCs), including polychlorinated biphenyls, dibenzo-p-dioxins, and dibenzofurans. While the long-distance atmospheric transport of these compounds has been well established, the importance of chemical reactions that may occur while SOCs are in the atmosphere is largely unknown. For most semi-volatile organic compounds in the vapor phase, the

Philip Neal Anderson

1995-01-01

316

Solubility of room-temperature ionic liquid in supercritical CO2 with and without organic compounds.  

PubMed

Ionic liquid can dramatically dissolve in supercritical (sc) CO2 with polar organic compounds (ethanol, acetone) especially as the concentration of the compounds in scCO2 exceeds 10 mol%, while the effect of a nonpolar organic compound (n-hexane) in scCO2 on the solubility is very limited even when its concentration is as high as 30 mol%. PMID:12841267

Wu, Weize; Zhang, Jianmin; Han, Buxing; Chen, Jiawei; Liu, Zhimin; Jiang, Tao; He, Jun; Li, Wenjing

2003-06-21

317

Chemical process for the catalytic oxidation of formaldehyde and other organic compounds  

SciTech Connect

The invention discusses a chemical process for the catalytic oxidation of formaldehyde and other organic compounds contained in a dilute aqueous solution, particularly waste water. The inventive feature resides in the use of a cobalt catalyst to increase the rate of oxidation of the organic compounds when hypochlorous acid is the oxidant. The latter may be provided by a chlorine compound, such as sodium hypochlorite, calcium hypochlorite or chlorine gas dissolved in water.

Murphy, A.P.

1991-01-01

318

Enhanced transport of low-polarity organic compounds through soil by cyclodextrin  

Microsoft Academic Search

The removal of low-polarity organic compounds from soils and aquifers by water flushing is often constrained by sorption interactions. There is great interest in developing systems that can enhance the transport of organic compounds through porous media, thus facilitating remediation. We investigated the potential of hydroxypropyl-[beta]-cyclodextrin (HPCD), a microbially produced compound, to reduce the sorption and to enhance the transport

Mark L. Brusseau; Xiaojiang Wang; Qinhong Hu

1994-01-01

319

Headspace-SPME-GC-MS Identification of Volatile Organic Compounds Released from Expanded Polystyrene  

Microsoft Academic Search

A method for the identification of volatile organic compounds (VOCs) released from packaging expanded polystyrene (EPS) is presented. Headspace solid-phase microextraction (HS-SPME) with a 75-µm carboxen-polydimethylsiloxan fiber was used as sample preparation technique before the determination of the volatile organic compounds by gas chromatography–mass spectrometry (GC-MS). For separation of compounds, two fused silica capillary columns of different polarity (DB-5ms and

Peter Kusch; Gerd Knupp

2004-01-01

320

INVESTIGATIONS OF BIODEGRADABILITY AND TOXICITY OF ORGANIC COMPOUNDS  

EPA Science Inventory

The development of elaborate industrial societies has led to proliferation of a vast number of complex chemicals for industrial, agricultural and domestic use. Some portion of these compounds eventually find their way into municipal and industrial wastewater. Unless specifically ...

321

The Separation and Identification of Two Unknown Solid Organic Compounds: An Experiment for the Sophomore Organic Chemistry Laboratory  

ERIC Educational Resources Information Center

Segregation and recognition of two unfamiliar concrete organic compounds are achieved through microscale flash chromatography and spectroscopy plus melting point verifications respectively. This inexpensive and harmless microscale experiment for sophomore students ensures exercise in chromatographic and spectroscopic methods.

Feist, Patty L.

2004-01-01

322

The Separation and Identification of Two Unknown Solid Organic Compounds: An Experiment for the Sophomore Organic Chemistry Laboratory  

ERIC Educational Resources Information Center

|Segregation and recognition of two unfamiliar concrete organic compounds are achieved through microscale flash chromatography and spectroscopy plus melting point verifications respectively. This inexpensive and harmless microscale experiment for sophomore students ensures exercise in chromatographic and spectroscopic methods.|

Feist, Patty L.

2004-01-01

323

Influence of soil organic matter composition on the partition of organic compounds  

USGS Publications Warehouse

The sorption at room temperature of benzene and carbon tetrachloride from water on three high-organic-content soils (muck, peat, and extracted peat) and on cellulose was determined in order to evaluate the effect of sorbent polarity on the solute partition coefficients. The isotherms are highly linear for both solutes on all the organic matter samples, which is consistent with a partition model. For both solutes, the extracted peat shows the greatest sorption capacity while the cellulose shows the lowest capacity; the difference correlates with the polar-to-nonpolar group ratio [(O + N)/C] of the sorbent samples. The relative increase of solute partition coefficient (Kom) with a decrease of sample polar content is similar for both solutes, and the limiting sorption capacity on a given organic matter sample is comparable between the solutes. This observation suggests that one can estimate the polarity effect of a sample of soil organic matter (SOM) on Kom of various nonpolar solutes by determining the partition coefficient of single nonpolar solute when compositional analysis of the SOM is not available. The observed dependence of Kom on sample polarity is used to account for the variation of Kom values of individual compounds on different soils that results from change in the polar group content of SOM. On the assumption that the carbon content of SOM in "ordinary soils" is 53-63%, the calculated variation of Kom is a factor of ???3. This value is in agreement with the limit of variation of most Kom data with soils of relatively high SOM contents.

Rutherford, D. W.; Chiou, C. T.; Klle, D. E.

1992-01-01

324

Reactive uptake of ozone by liquid organic compounds  

NASA Astrophysics Data System (ADS)

The reaction probability of ozone on the surface of several different organic liquids is measured. Ozone reacts efficiently (??10-2-10-3) with organic liquids containing double bonds (1-tridecene, ?-pinene, toluene, methacrolein and canola oil), and much less efficiently with an aldehyde, a ketone (tridecanal, 2-tridecanone; ??10-4), an alkane, an alcohol and an acid (tridecane, 1-tridecanol, tridecanoic acid; ??10-5). The results suggest that heterogeneous reactions with organic aerosol can be an important loss process for tropospheric ozone, if the aerosol contains unsaturated organic material.

de Gouw, Joost A.; Lovejoy, Edward R.

325

Compendium of methods for the determination of toxic organic compounds in ambient air, June 1988  

SciTech Connect

This Compendium was prepared to provide regional, state, and local environmental regulatory agencies, as well as other interested parties, with specific guidance on the determination of selected toxic organic compounds in ambient air. The decision was made to begin preparation of a Compendium that would provide specific sampling and analysis procedures, in a standardized format, for selected toxic organic compounds. The current Compendium consists of fourteen procedures considered to be of primary importance in current toxic organic monitoring efforts.

Winberry, W.T.; Murphy, N.T.; Riggan, R.M.

1988-06-01

326

Chemical characterization of water soluble organic compounds in tropospheric fine aerosol  

NASA Astrophysics Data System (ADS)

Water soluble organic compounds were investigated in aerosol samples collected in a rural station in Hungary. The share of water soluble organic carbon (WSOC) reached 58% of the total carbon and 40% of the water soluble species (both organic and inorganic). Most of the WSOC was characterized by polyconjugated (e.g. aromatic) structure, acidic functional groups and a continuous distribution in the mass to charge ratio between 100 and 700. Individual compounds with molecular weight of several hundreds have also been detected. .

Kiss, G.; Gelencsér, A.; Hoffer, A.; Krivácsy, Z.; Mészáros, E.; Molnár, A.; Varga, B.

2000-08-01

327

Effects of airborne volatile organic compounds on plants.  

PubMed

Routine measurements of volatile organic compounds (VOCs) in air have shown that average concentrations are very much smaller than those used in laboratory experiments designed to study the effects of VOCs on plants. However, maximum hourly concentrations of some VOCs can be 100 times larger than the average, even in rural air. Experimental studies have rarely extended for longer than a few days, so there is little information on potential long-term effects of exposure to small concentrations. This review considers the available evidence for long-term effects, based on laboratory and field data. Previous reviews of the literature from Germany and the USA are cited, prior to an assessment of the effects of individual VOCs. Although hydrocarbons from vehicle exhausts have been implicated in the observed effects on roadside vegetation, the evidence suggests that it is the nitrogen oxides in the exhaust gases that are mostly responsible. There is evidence that aromatic hydrocarbons can be metabolised in plants, although the fate of the metabolites is not known. There is a large literature on the effects of ethylene, because of its role as a plant hormone. Effects have been reported in the field, in response to industrial emissions, and dose-response experiments over several weeks in laboratory studies have clearly identified the potential for effects at ambient concentrations. The main responses are morphological (e.g. epinasty), which may be reversible, and on the development of flowers and fruit. Effects on seed production may be positive or negative, depending on the exposure concentration. Chlorinated hydrocarbons have been identified as potentially harmful to vegetation, but only one long-term experiment has studied dose-response relationships. As for ethylene, the most sensitive indication of effect was on seed production, although long-term accumulation of trichloroacetic acid in tissue may also be a problem. There is little evidence of the direct effects of oxygenated hydrocarbons on plants. Plants are a significant emission source of short-chain alcohols, aldehydes and ketones. Peroxyacetyl nitrate (PAN) has a well-documented history as damaging to vegetation. There have been few long-term experimental studies despite the field evidence for damaging effects. Early studies in California have been followed by more recent data from east Asia, but there is still a dearth of information on the potential for effects of PAN and related peroxyacyl nitrates on vegetation typical of regions around tropical and sub-tropical cities where PAN pollution is increasingly important. The lack of long-term measurements, coupled with the available evidence that effects are not linearly related to 'dose' measured as the product of exposure concentration and time, means that the possibility of adverse effects of VOCs on vegetation cannot be safely rejected, particularly in urban and industrial areas. Although reproductive processes (flowering, seed production) appear to be most sensitive, there have been no experimental studies on subsequent seed viability and the consequences at the ecosystem level of changes to plant phenology. The potential for VOC metabolites to accumulate in plant tissue has been demonstrated, but any subsequent effects on herbivores and phytophagous insects have yet to be investigated. PMID:12535603

Cape, J N

2003-01-01

328

Rapid NMR method for the quantification of organic compounds in thin stillage.  

PubMed

Thin stillage contains organic and inorganic compounds, some of which may be valuable fermentation coproducts. This study describes a thorough analysis of the major solutes present in thin stillage as revealed by NMR and HPLC. The concentration of charged and neutral organic compounds in thin stillage was determined by excitation sculpting NMR methods (double pulse field gradient spin echo). Compounds identified by NMR included isopropanol, ethanol, lactic acid, 1,3-propanediol, acetic acid, succinic acid, glycerophosphorylcholine, betaine, glycerol, and 2-phenylethanol. The concentrations of lactic and acetic acid determined with NMR were comparable to those determined using HPLC. HPLC and NMR were complementary, as more compounds were identified using both methods. NMR analysis revealed that stillage contained the nitrogenous organic compounds betaine and glycerophosphorylcholine, which contributed as much as 24% of the nitrogen present in the stillage. These compounds were not observed by HPLC analysis. PMID:21875138

Ratanapariyanuch, Kornsulee; Shen, Jianheng; Jia, Yunhua; Tyler, Robert T; Shim, Youn Young; Reaney, Martin J T

2011-09-15

329

Organic compounds in the water column of the eastern Baltic  

SciTech Connect

This article describes the transport, distribution, concentration, chemistry, environmental consequences, and chemical control strategies of organic wastes--including waste hydrocarbons, industrial effluents and oil spills--in the Baltic Sea and in the regions along its shorelines. Data on seasonal and compositional variations in organic waste content are provided.

Nemirovskaya, I.A.; Nesterova, M.P.; Pustel'nikov, O.S.

1987-11-01

330

METHODS OF REDUCING WATER CONTAMINANTS: REMOVAL OF ORGANIC COMPOUNDS  

EPA Science Inventory

Much of the recent concern by regulatory agencies about drinking water quality has been directed toward organic contamination in drinking water. lthough organic contamination has been thought to primarily affect surface waters, there is a growing awareness and concern over ground...

331

Development and validation of an automated monitoring system for oxygenated volatile organic compounds and nitrile compounds in ambient air  

Microsoft Academic Search

Few studies were conducted on oxygenated volatile organic compounds (OVOC) because of problems encountered during the sampling\\/analyzing steps induced by water in sampled air. Consequently, there is a lack of knowledge of their spatial and temporal trends and their origins in ambient air. In this study, an analyzer consisted of a thermal desorber (TD) interfaced with a gas chromatograph (GC)

J. Roukos; H. Plaisance; T. Leonardis; M. Bates; N. Locoge

2009-01-01

332

Correlation of liquid densities of some halogenated organic compounds  

Microsoft Academic Search

Experimental saturated and compressed liquid densities of 15 halogenated hydrocarbons have been correlated using the Hankinson-Thomson correlation and the liquid density model proposed by Aalto et al. New pure component parameters have been obtained and are reported here for the fluids studied, which are considered as potential alternative refrigerants. The compounds included in this work are trichlorofluoromethane (R11). chlorodifluoromethane (R22),

Mika M. Aalto

1997-01-01

333

Reactivity of nitrogenous and other organic compounds with aqueous chlorine  

Microsoft Academic Search

Chlorine has been used to disinfect municipal water supplies in this country since 1908. Chlorine has become the primary drinking water disinfectant in the United States used to prevent the transmission of waterborne diseases. Free aqueous chlorine exists as hypochlorous acid (HOCI) and hypochlorite ion (OCI-). These forms react readily with ammonia and other nitrogenous compounds to form combined chlorine

Edward L. Katz

1986-01-01

334

Green Synthetic Alternatives to Organic Compounds and Nanomaterials  

EPA Science Inventory

A brief account of reactions involving microwave (MW) exposure of neat reactants or catalyzed by mineral support surfaces, such as alumina, silica, clay, or their ?doped? versions, for the rapid one-pot assembly of heterocyclic compounds from in situ generated reactive intermedia...

335

Separation of volatile organic compounds by pervaporation for a binary compound combination: Trichloroethylene and 1,1,1-trichloroethane  

SciTech Connect

This study evaluates the behavior of sweeping air pervaporation when used to separate trichloroethylene (TCE) and 1,1,1-trichloroethane (TCEthane) from wastewater. Selectivity and membrane preference are studied. Models for binary compounds are studied to evaluate the extent of cross influence on TCE flux due to the presence of another volatile organic compound, TCEthane. Using the models, the integral dry diffusion coefficient for TCEthane is evaluated. Results indicate that the membrane exhibits a preference for TCE over TCEthane. However, the values of the diffusion rates are found to be comparable. Selectivity values are found to be independent of the air flow rate but dependent on the relative concentration of the compounds in the feed solution. It is found that, due to the presence of TCEthane, the flux of TCE decreased. Further, it is found that the ratio of the integral dry diffusion coefficients of the compounds is inversely proportional to the ratio of their molecular weights.

Visvanathan, C.; Basu, B. [Asian Inst. of Tech., Bangkok (Thailand). Environmental Engineering Program; Mora, J.C. [Inst. National Polytechnique de Toulouse (France)

1995-11-01

336

MEASUREMENT OF POLYCYCLIC ORGANIC MATERIALS AND OTHER HAZARDOUS ORGANIC COMPOUNDS IN STACK GASES - STATE OF THE ART  

EPA Science Inventory

This report documents and reviews state-of-the-art methods for the measurement of polycyclic organic matter (POM) and other hazardous organic materials which are present in industrial stack emissions. Measurement methods for many hazardous compounds, such as POM and nitrosamines,...

337

Secondary organic aerosols formed from oxidation of biogenic volatile organic compounds in the Sierra Nevada Mountains of California  

Microsoft Academic Search

Biogenic volatile organic compound (BVOC) emissions, such as isoprene and terpenes, can be oxidized to form less volatile carbonyls, acids, and multifunctional oxygenated products that may condense to form secondary organic aerosols (SOA). This research was designed to assess the contribution of oxidized BVOC emissions to SOA in coniferous forests by collecting high-volume particulate samples for 6 days and 5

Thomas M. Cahill; Vincent Y. Seaman; M. Judith Charles; Rupert Holzinger; Allen H. Goldstein

2006-01-01

338

Emission of volatile organic compounds during composting of municipal solid wastes  

Microsoft Academic Search

The objective of this study was to identify and quantify volatile and semi-volatile organic compounds (VOCs) produced during composting of the organic fraction of municipal solid wastes (MSW). A laboratory experiment was conducted using organic components of MSW that were decomposed under controlled aerobic conditions. Mixed paper primarily produced alkylated benzenes, alcohols and alkanes. Yard wastes primarily produced terpenes, alkylated

Dimitris P Komilis; Robert K Ham; Jae K Park

2004-01-01

339

EMISSION OF ORGANIC COMPOUNDS AND COMBUSTION GASES DURING HAZARDOUSWASTE COFIRING IN A WATERTUBE PACKAGE BOILER  

EPA Science Inventory

The primary objective of this study was to evaluate the sorptionand desorption of organic compounds on combustion-generated sootduring the cofiring of hazardous organics with fuel oil in afull-scale boiler. orption of organics was accomplished by firinga watertube package boiler ...

340

ORGANIC COMPOUNDS MEASURED IN PM2.5 DURING NEOPS  

EPA Science Inventory

Secondary formation of submicron ambient particulate matter occurs when organic and inorganic constituents having sufficiently low volatility condense onto preexisting particles in the atmosphere. The presence of the resulting submicron particles has led to three important env...

341

MEASUREMENT OF ORGANIC COMPOUND EMISSIONS USING SMALL TEST CHAMBERS  

EPA Science Inventory

The paper discusses the measurement of organic emissions from a variety of indoor materials, using small (166 liter) environmental test chambers. he following materials were tested: adhesives, caulks, pressed wood products, floor waxes, paints, and solid insecticides. or each mat...

342

Uptake and Assimilation of Organic Compounds by Marine Protists.  

National Technical Information Service (NTIS)

An analysis of the capacity of the phytoplankter, Platymonas subcordiformis, to take up and assimilate dissolved amino acids was made. This takes place very rapidly at low ambient concentrations. When the organism is grown under conditions of low nutrient...

G. C. Stephens

1969-01-01

343

Organic compounds in rainfall at Hornsund SW Spitsbergen: qualitative results  

Microsoft Academic Search

Abstract: Research on the chemistry of atmospheric precipitation in the Hornsund region of Svalbard has been extended by analysis of the organic contents. In rainfall samples col? lected in September 2003, the organics were separated by solid phase extraction (SPE), eluted and analysed on gas chromatograph,coupled to a mass selective detector (GC\\/MS). Rainfall pH was in the range 4.72–5.45, the

Wies?awa Ewa Krawczyk; Urszula Skr?t

344

Organic-Inorganic Layer Compounds as Molecular Functional Materials  

Microsoft Academic Search

Many molecular charge transfer salts synthesised over the last 20 years contain alternating layers of organic donor cations and inorganic metal-complex anions. Here we survey some features of one of the most prolific families of such salts: (BEDT-TTF)4[AM(C2O4)3]. G, where BEDT-TTF is bis-ethylene-dithiotetrathiafulvalene, A is a monopositive cation, M a tri-positive cation and G an organic guest molecule. The roles

Peter Day

2006-01-01

345

[Using compost of agricultural solid waste to produce organic-inorganic compound fertilizer].  

PubMed

Techniques of compound fertilizer production from solid waste compost were studied. Different ratio of water moisture, proportion between organic and inorganic and infection of different granularity to the effect of granulation is separately determined through experiments at the pilot scale in the field. The optimal parameters of the techniques are determined. The moisture content is 35%-40%; the rate of organic matter is 80%-90%; granularity is 20 mu. According the data of the organism's concentration, height and weight in crop, the crop was fertilized compound fertilizer is batter than chemical fertilizer. And the ability of increasing the production of the compound fertilizer was testified. PMID:16881331

Yang, Bo-jing; Wang, Hong-tao

2006-07-01

346

Organic phase resistance to dissolution of polycyclic aromatic hydrocarbon compounds  

SciTech Connect

The dissolution of naphthalene, phenanthrene, and pyrene from viscous organic phases into water was studied in continuous-flow systems for time periods ranging from several months to more than 1 year. By selecting nonaqueous phases ranging from low viscosity to semisolid, i.e., from a light lubricating oil to paraffin, the governance of mass transfer was shown to vary from water phase control to nonaqueous phase control. An advancing depleted-zone model is proposed to explain the dissolution of PAHs from a viscous organic phase wherein the formation of a depleted zone within the organic phase increases the organic phase resistance to the dissolution of PAHs. The experimental data suggest the formation of a depleted zone within the organic phase for systems comprising a high-viscosity oil, petrolatum (petroleum jelly), and paraffin. Organic phase resistance to naphthalene dissolution became dominant over aqueous phase resistance after flushing for several days. Such effects were not evident for low viscosity lubricating oil. The transition from aqueous-phase dissolution control to nonaqueous-phase dissolution control appears predictable, and this provides a more rational framework to assess long-term release of HOCs from viscous nonaqueous phase liquids and semisolids.

Ortiz, E.; Kraatz, M.; Luthy, R.G. [Carnegie Mellon Univ., Pittsburgh, PA (United States). Dept. of Civil and Environmental Engineering

1999-01-15

347

Charge-density matching in organic–inorganic uranyl compounds  

Microsoft Academic Search

Single crystals of [C10H26N2][(UO2)(SeO4)2(H2O)](H2SeO4)0.85(H2O)2 (1), [C10H26N2][(UO2)(SeO4)2] (H2SeO4)0.50(H2O) (2), and [C8H20N]2[(UO2)(SeO4)2(H2O)] (H2O) (3) were prepared by evaporation from aqueous solution of uranyl nitrate, selenic acid and the respective amines. The structures of the compounds have been solved by direct methods and structural models have been obtained. The structures of the compounds 1, 2, and 3 contain U and Se atoms in

Sergey V. Krivovichev; Ivan G. Tananaev; Boris F. Myasoedov

2007-01-01

348

Preparation of certain organic compounds labeled with carbon-14  

Microsoft Academic Search

Chemical preparation of the following compounds is described: n-decane-; 2C¹⁴, decanone-5-5C¹⁴, decanone-5-6C¹⁴, decanone-54C¹⁴, ; decanone-3-3C¹⁴, decanone-2-2C¹⁴, 2-heptanone-2C¹⁴ , decanol-4-; 5C¹⁴, and 1-methylcyclohexane-1C¹⁴. (LK);

A. M. Synroezhko; N. T. Selivanov

1973-01-01

349

Organic sulfur compounds in crude oils of West Kazakhstan  

Microsoft Academic Search

The group composition of these compounds in the crude oils and cuts was determined by methods that have been used previously [1-4]. The data are listed in Table 1. The oils from the Tortai, Kultuk, and Zhilankabak fields are classed as low-sulfur(total sulfur contents 0.22%, 0.44%, and 0.47%, respectively). The yield of light cuts below 200~C varies from 7.7%to 30.4%,

V. V. Ryzhenko; A. V. Kotova; N. S. Buyanova; N. K. Nadirov

1982-01-01

350

Analysis of organic sulfur compounds in wine aroma.  

PubMed

Sulfur-containing compounds in wines have been extensively studied because of their effect on wine aroma. The aim of this paper was to give an overview on the analytical methods developed to determine them in wines with special emphasis on gas chromatographic methods, as well as the results obtained. In addition, the problems occurring in application of the common extraction procedures, such as liquid-liquid extraction, static and dynamic headspace and solid-phase microextraction, are presented and discussed. PMID:10905736

Mestres, M; Busto, O; Guasch, J

2000-06-01

351

Transformations of halogenated organic compounds under denitrification conditions.  

PubMed Central

Trihalomethanes, carbon tetrachloride, 1,1,1-trichloroethane, 1,2-dibromoethane, chlorinated benzenes, ethylbenzene, and naphthalene at concentrations commonly found in surface and groundwater were incubated under anoxic conditions to study their transformability in the presence of denitrifying bacteria. None of the aromatic compounds showed significant utilization relative to sterile controls at initial concentrations from 41 to 114 micrograms/liter after 11 weeks of incubation. Of the halogenated aliphatic compounds studied, transformations of carbon tetrachloride and brominated trihalomethanes were observed after 8 weeks in batch denitrification cultures. Carbon from the decomposition of carbon tetrachloride was both assimilated into cell material and mineralized to carbon dioxide. How this was possible remains unexplained, since carbon tetrachloride is transformed to CO2 by hydrolysis and not by oxidation-reduction. Chloroform was detected in bacterial cultures with carbon tetrachloride initially present, indicating that reductive dechlorination had occurred in addition to hydrolysis. The data suggest that transformations of certain halogenated aliphatic compounds are likely to occur under denitrification conditions in the environment.

Bouwer, E J; McCarty, P L

1983-01-01

352

Biodegradation of volatile organic compounds from paint industries.  

PubMed

Methyl ethyl ketone (MEK) and methyl iso-butyl ketone (MIBK) constitute significant proportion of the total VOC emissions from manufacturing and application processes of surface coatings. Biodegradation of MEK and MIBK using an acclimatized mixed culture was evaluated, under aerobic condition. Biodegradation studies were carried out using MEK and MIBK as single substrates and in combination. Mixed-pollutant studies were conducted in MEK-dominated system, MIBK-dominated system, and MEK-MIBK equi-concentration systems to understand the concentration-dependent interaction of these compounds in a biosystem. Experimental data obtained from single-pollutant system was used to estimate the biokinetic parameters, viz. ?(max), K(s), K(i), and Y(T), for these compounds. Among the several bio-kinetic models tested, Monod inhibition model was best suited for predicting the biodegradation of these two VOCs. Four multiple-substrate models, viz. no-interaction, competitive, un-competitive, and non-competitive were used to study the nature of inhibition for different combinations of these compounds. The biodegradation of MEK and MIBK mixtures was found to be best described by competitive inhibition model. However, the predictions were not very good for systems where MEK concentration was higher than MIBK concentration. PMID:22573008

Datta, Aviraj; Philip, Ligy

2012-05-10

353

In situ measurements of gas/particle-phase transitions for atmospheric semivolatile organic compounds.  

PubMed

An understanding of the gas/particle-phase partitioning of semivolatile compounds is critical in determining atmospheric aerosol formation processes and growth rates, which in turn affect global climate and human health. The Study of Organic Aerosol at Riverside 2005 campaign was performed to gain a better understanding of the factors responsible for aerosol formation and growth in Riverside, CA, a region with high concentrations of secondary organic aerosol formed through the phase transfer of low-volatility reaction products from the oxidation of precursor gases. We explore the ability of the thermal desorption aerosol gas chromatograph (TAG) to measure gas-to-particle-phase transitioning for several organic compound classes (polar and nonpolar) found in the ambient Riverside atmosphere by using in situ observations of several hundred semivolatile organic compounds. Here we compare TAG measurements to modeled partitioning of select semivolatile organic compounds. Although TAG was not designed to quantify the vapor phase of semivolatile organics, TAG measurements do distinguish when specific compounds are dominantly in the vapor phase, are dominantly in the particle phase, or have both phases present. Because the TAG data are both speciated and time-resolved, this distinction is sufficient to see the transition from vapor to particle phase as a function of carbon number and compound class. Laboratory studies typically measure the phase partitioning of semivolatile organic compounds by using pure compounds or simple mixtures, whereas hourly TAG phase partitioning measurements can be made in the complex mixture of thousands of polar/nonpolar and organic/inorganic compounds found in the atmosphere. PMID:20142511

Williams, Brent J; Goldstein, Allen H; Kreisberg, Nathan M; Hering, Susanne V

2010-02-08

354

Xenobiotic organic compounds in runoff from fields irrigated with treated wastewater.  

PubMed

Investigations of agricultural nonpoint source pollution typically focus on a relatively narrow range of targeted toxic and biostimulatory compounds (e.g., specific pesticides, nutrients). Regular application of numerous other organic compounds to agricultural fields in pesticide formulations, irrigation water, soil amendments, and fertilizers may result in their transport into surface waters via runoff. We examined whether potentially toxic dissolved and particle-associated "nontarget" organic compounds were present in surface runoff from agricultural fields irrigated with disinfected tertiary recycled water or wastewater effluent-dominated streamwater. Gas chromatographic-mass spectrometric analyses of filtered runoff samples revealed the presence of numerous nontarget compounds of potential toxicological significance including pesticide transformation products, pesticide adjuvant chemicals, plasticizers, flame retardants, pharmaceuticals, and personal care product ingredients. Although the toxicity of many of these compounds is poorly characterized, some may elicit subtle but profound toxicological effects. Agricultural runoff also represented a source of allochthonous natural organic matter to the stream system. PMID:12590482

Pedersen, Joel A; Yeager, Matt A; Suffet, I H

2003-02-26

355

AQUATIC PHOTOLYSIS OF OXY-ORGANIC COMPOUNDS ADSORBED ON GOETHITE.  

USGS Publications Warehouse

Organic materials that will not absorb light at wavelengths longer than 295 nanometers (the solar wavelength cutoff) may nevertheless, undergo electron transfer reactions initiated by light. These reactions occur when the organic materials are adsorbed as ligand complexes to the surface of iron oxy-hydroxide (goethite). The adsorbed materials can be either inner or outer coordination sphere complexes. Goethite was chosen as the iron oxyhydroxide surface because it has the highest thermodynamic stability of any of the oxyhydroxides in water and it can be synthesized easily, with high purity.

Goldberg, Marvin, C.

1985-01-01

356

A new organic compound for the synthesis of gold nanoparticles  

Microsoft Academic Search

2,3,5,6-Tetrakis-(morpholinomethyl)hydroquinone (1) is used for the first time in the preparation of gold nanoparticles by the reduction of HAuCl4 in water–methanol medium without using any capping agent. Compound 1 was prepared by Mannich-type aminomethylation of hydroquinone with morpholine. It is characterized by elemental analysis, FT-IR, UV–Vis and mass spectra and finally by single crystal X-ray diffraction. The ratio of HAuCl4

Partha Roy; Koushik Dhara; Mario Manassero; Pradyot Banerjee

2008-01-01

357

Development of technology performance specifications for volatile organic compounds  

Microsoft Academic Search

The Office of Technology Development (OTD) within the Office of Environmental Restoration and Waste Management of the Department of Energy has a mission to deliver needed and usable technologies to its customers. The primary customers are individuals and organizations performing environmental characterization and remediation, waste cleanup, and pollution prevention at DOE sites. DOE faces a monumental task in cleaning up

C. Purdy; W. E. Schutte; M. D. Erickson; S. C. Carpenter; P. V. Doskey; P. C. Lindahl; A. D. Pflug

1993-01-01

358

ENZYMATIC PROCESSES USED BY PLANTS TO DEGRADE ORGANIC COMPOUNDS  

EPA Science Inventory

This is a review of recent plant enzyme systems that have been studied in uptake and transformation of organic contaminants. General procedures of plant preparation and enzyme isolation are covered. Six plant enzyme systems have been investigated for activity with selected pollut...

359

Anaerobic degradation of organic compounds at high salt concentrations  

Microsoft Academic Search

A number of obligately anaerobic fermentative bacteria are known to degrade a variety of organic substrates such as sugars, amino acids, and others, in the presence of high salt concentrations (up to 3–4 M) to products such as hydrogen, CO2, acetate and higher fatty acids, and ethanol. Our understanding of the fate of these products in hypersaline environments is still

Aharon Oren

1988-01-01

360

ORGANIC AND ORGANOTIN COMPOUNDS LEACHED FROM PVC AND CPVC PIPE  

EPA Science Inventory

The primary objective of this research program was to determine whether organotins, contained in heat stabilizers of polyvinyl chloride (PVC) and chlorinated polyvinyl chloride (CPVC) pipe, and other organics present in pipe sealing cement solvents may leach into potable water su...

361

Neurotoxic Effects of Controlled Exposure to a Complex Mixture of Volatile Organic Compounds.  

National Technical Information Service (NTIS)

Subjective reactions of discomfort, impaired air quality, irritation of mucosal membranes, and impaired memory have been reported in chemically sensitive subjects during exposure to volatile organic compounds (VOCs) found in new buildings. 66 normal healt...

D. A. Otto L. Molhave H. K. Hudnell G. Goldstein J. O'Neil

1990-01-01

362

Preliminary evaluation of selected in situ remediation technologies for Volatile Organic Compound contamination at Arid sites.  

National Technical Information Service (NTIS)

To support the Volatile Organic Compounds-Arid Site (VOC-Arid) Integrated Demonstration (ID) in its technical, logistical, institutional, and economical testing of emerging environmental management and restoration technologies. Pacific Northwest Laborator...

R. J. Lenhard M. A. Gerber J. E. Amonette

1992-01-01

363

Diamagnetic susceptibility contribution of methylene group (-CH2-) in different classes of organic compounds  

NASA Astrophysics Data System (ADS)

This document is part of Subvolume C `Diamagnetic Susceptibility and Magnetic Anisotropy of Organic Compounds' of Volume 27 `Diamagnetic Susceptibility and Anisotropy' of Landolt-Börnstein - Group II Molecules and Radicals.

Kumar, M.; Gupta, R.

364

Indoor Residence Times of Semivolatile Organic Compounds: Model Estimation and Field Evaluation  

EPA Science Inventory

Indoor residence times of semivolatile organic compounds (SVOCs) are a major and mostly unavailable input for residential exposure assessment. We calculated residence times for a suite of SVOCs using a fugacity model applied to residential environments. Residence times depend on...

365

Plant-Associated Bacterial Degradation of Toxic Organic Compounds in Soil  

PubMed Central

A number of toxic synthetic organic compounds can contaminate environmental soil through either local (e.g., industrial) or diffuse (e.g., agricultural) contamination. Increased levels of these toxic organic compounds in the environment have been associated with human health risks including cancer. Plant-associated bacteria, such as endophytic bacteria (non-pathogenic bacteria that occur naturally in plants) and rhizospheric bacteria (bacteria that live on and near the roots of plants), have been shown to contribute to biodegradation of toxic organic compounds in contaminated soil and could have potential for improving phytoremediation. Endophytic and rhizospheric bacterial degradation of toxic organic compounds (either naturally occurring or genetically enhanced) in contaminated soil in the environment could have positive implications for human health worldwide and is the subject of this review.

McGuinness, Martina; Dowling, David

2009-01-01

366

Supercritical Fluid Extraction of Organic Compounds from Solids and Aqueous Solutions.  

National Technical Information Service (NTIS)

In this thesis, the extraction of organic compounds from solid and liquid matrices using supercritical carbon dioxide as a solvent was studied. Dense carbon dioxide is a very good solvent for the cyclic amide, 6-caprolactam. 6-caprolactam exhibits relativ...

A. Laitinen

2000-01-01

367

Emissions of Volatile and Potentially Toxic Organic Compounds from Sewage Treatment Plants and Collection Systems.  

National Technical Information Service (NTIS)

Publicly-owned treatment works (POTWs) are a source of potentially toxic organic compound (PTOC) emissions for which limited data are available. The study assesses the potential for PTOC emissions from municipal wastewater treatment plants (MWTPs) and col...

D. P. Y. Chang E. D. Schroeder R. L. Corsi

1987-01-01

368

SOIL SORPTION OF VOLATILE AND SEMIVOLATILE ORGANIC COMPOUNDS IN A MIXTURE  

EPA Science Inventory

Studies were conducted to evaluate lipophilicity as a predictor sorption for a mixture of organic compounds with high vapor pressures commonly present at hazardous waste sites. Sorption partition coefficients (Kp) for the mixture of 16 volatile and semivolatile ...

369

Development of a Universally Accepted Test Method for Volatile Organic Compounds.  

National Technical Information Service (NTIS)

Test methods published by the American Society for Testing and Materials (ASTM) and used for the determination of Volatile Organic Compound (VOC) content of coatings are known to have cumulatively poor reproducibility. The VOC calculations are contained i...

D. P. Fairley R. Gill R. Haffner

1991-01-01

370

Compendium of methods for the determination of toxic organic compounds in ambient air  

SciTech Connect

Determination of toxic organic compounds in ambient air is a complex task, primarily because of the wide variety of compounds of interest and the lack of standardized sampling and analysis procedures. This compendium of methods was prepared to provide current, peer-reviewed procedures in a standardized, written format for measuring toxic organic pollutants of primary importance in ambient air. The various methods provide both sampling and analytical procedures for a variety of pollutants, including pesticides, PCBs, formaldehyde and other aldehydes, phosgene, n-nitrosodimethylamine, cresol/phenol, dioxin, non-speciated non-methane organic compounds, polynuclear aromatic hydrocarbons, and various other volatile nonpolar organic compounds. The compendium is a consolidation and republishing of Methods T01-105 from the original Compendium (EPA 600/4-84-041), Methods T06-T09 from the First Supplement (EPA-600/4-87-006), and T010-T014 from the Second Supplement (EPA-600/4-89/018).

Riggin, R.M.; Winberry, W.T.; Murphy, N.T.

1988-06-01

371

Nonmethane Organic Compound and Three-Hour Air Toxics Monitoring Program, 1990.  

National Technical Information Service (NTIS)

In certain areas of the country where the National Ambient Air Quality Standard (NAAQS) for ozone is being exceeded, additional measurements of ambient nonmethane organic compounds (NMOC) are needed to assist the affected States in developing revised ozon...

R. A. McAllister P. L. O'Hara D. P. Dayton J. E. Robbins R. F. Jongleux

1991-01-01

372

Analysis of Ambient Polar Volatile Organic Compounds Using Chemical Ionization-Ion Trap Detector.  

National Technical Information Service (NTIS)

The current approach to measuring trace levels of volatile organic compounds (VOCs) in ambient air requires cryogenic trapping of the analytes, followed by thermal desorption and low-temperature refocusing onto a column for analysis by capillary gas chrom...

S. M. Gordon M. Miller

1989-01-01

373

FIELD EVALUATION OF A SIMPLE MICROCOSM SIMULATING THE BEHAVIOR OF VOLATILE ORGANIC COMPOUNDS IN SUBSURFACE MATERIALS  

EPA Science Inventory

A simple batch microcosm had previously been developed to simulate the behavior of volatile organic compounds in unconsolidated subsurface material. The microcosm was evaluated by comparing the behavior of tetrachloroethylene, bromoform, carbon tetrachloride, 1,2-dichlorobenzene,...

374

Detection, Composition and Treatment of Volatile Organic Compounds from Waste Treatment Plants  

PubMed Central

Environmental policies at the European and global level support the diversion of wastes from landfills for their treatment in different facilities. Organic waste is mainly treated or valorized through composting, anaerobic digestion or a combination of both treatments. Thus, there are an increasing number of waste treatment plants using this type of biological treatment. During waste handling and biological decomposition steps a number of gaseous compounds are generated or removed from the organic matrix and emitted. Different families of Volatile Organic Compounds (VOC) can be found in these emissions. Many of these compounds are also sources of odor nuisance. In fact, odors are the main source of complaints and social impacts of any waste treatment plant. This work presents a summary of the main types of VOC emitted in organic waste treatment facilities and the methods used to detect and quantify these compounds, together with the treatment methods applied to gaseous emissions commonly used in composting and anaerobic digestion facilities.

Font, Xavier; Artola, Adriana; Sanchez, Antoni

2011-01-01

375

POLAR ORGANIC COMPOUNDS IN FINE PARTICLES FROM THE NEW YORK, NEW JERSEY, AND CONNECTICUT REGIONAL AIRSHED  

EPA Science Inventory

Five key scientific questions guiding this research were explored. They are given here with results generated from the project.   B.1.        How can polar organic compounds be measured in atmospheric fine particulate matter? Is there potential a...

376

COMPARISON OF THE METHODS FOR COLLECTING INTERSTITIAL WATER FOR TRACE ORGANIC COMPOUNDS AND METAL ANALYSES  

EPA Science Inventory

Several common materials and methods used to collect interstitial water were evaluated to determine their effect on the accuracy and precision of measured concentrations of selected organic compounds and metals. e compared the concentration of pollutants in doses seawater before ...

377

Metabolism Summaries of Selected Halogenated Organic Compounds in Human and Environmental Media, A Literature Survey.  

National Technical Information Service (NTIS)

The Office of Program Integration and Infomation's Survey and Analysis Division is currently conducting a preliminary assessment of halogenated organic compounds in human and environmental media. This effort was undertaken in response to the detection and...

C. M. Latanich J. A. Caldwell J. D. Wiese R. D. Huffman T. K. Collins

1979-01-01

378

PREDICTION OF THE VAPOR PRESSURE, BOILING POINT, HEAT OF VAPORIZATION AND DIFFUSION COEFFICIENT OF ORGANIC COMPOUNDS  

EPA Science Inventory

The prototype computer program SPARC has been under development for several years to estimate physical properties and chemical reactivity parameters of organic compounds strictly from molecular structure. SPARC solute-solute physical process models have been developed and tested...

379

PREDICTION OF CHEMICAL REACTIVITY PARAMETERS AND PHYSICAL PROPERTIES OF ORGANIC COMPOUNDS FROM MOLECULAR STRUCTURE USING SPARC  

EPA Science Inventory

The computer program SPARC (SPARC Performs Automated Reasoning in Chemistry) has been under development for several years to estimate physical properties and chemical reactivity parameters of organic compounds strictly from molecular structure. SPARC uses computational algorithms...

380

ESTIMATION OF PHYSICAL PROPERTIES AND CHEMICAL REACTIVITY PARAMETERS OF ORGANIC COMPOUNDS  

EPA Science Inventory

The computer program SPARC (Sparc Performs Automated Reasoning in Chemistry)has been under development for several years to estimate physical properties and chemical reactivity parameters of organic compounds strictly from molecular structure. SPARC uses computational algorithms ...

381

Performance specifications for technology development: Application for characterization of volatile organic compounds in the environment.  

National Technical Information Service (NTIS)

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 chromatogra...

S. E. Carpenter P. V. Doskey M. D. Erickson P. C. Lindahl

1994-01-01

382

Total Exposure and Risk Assessment for Drinking Water Contaminated with Volatile Organic Compounds.  

National Technical Information Service (NTIS)

A total exposure and cancer risk assessment was conducted on nine volatile organic compounds (VOCs) frequently found in contaminated drinking water. Routes of exposure considered in the analysis included ingestion, inhalation and dermal uptake. A total of...

J. M. Clark C. L. Fuller

1987-01-01

383

40 CFR Appendix Viii to Part 266 - Organic Compounds for Which Residues Must Be Analyzed  

Code of Federal Regulations, 2010 CFR

...Must Be Analyzed VIII Appendix VIII to Part 266 Protection of Environment ENVIRONMENTAL PROTECTION...OF HAZARDOUS WASTE MANAGEMENT FACILITIES Pt. 266, App. VIII Appendix VIII to Part 266âOrganic Compounds for Which Residues Must...

2009-07-01

384

VOLATILE ORGANIC COMPOUNDS INHIBIT HUMAN AND RAT NEURONAL NICOTINIC ACETYLCHOLINE RECEPTORS EXPRESSED IN XENOPUS OOCYTES.  

EPA Science Inventory

This manuscript provides evidence to indicate that rats and humans are equally sensitive at the pharmacodynamic level to effects of volatile organic compounds. ? This manuscript also presents novel data that provides a plausible mechanism, disruption of ion channel functi...

385

VOLATILE ORGANIC COMPOUNDS IN INDOOR AIR: A SURVEY OF VARIOUS STRUCTURES  

EPA Science Inventory

Co-workers collected indoor air samples in their homes in SUMMA polished canisters. Upon receipt in the laboratory, the whole air samples were analyzed for volatile organic compounds (VOCs) using cryogenic sample preconcentration and subsequent capillary column chromatography. Ea...

386

National Ambient Volatile Organic Compounds (VOCs) Data Base, 1970-1987 (for Microcomputers),  

National Technical Information Service (NTIS)

The National Ambient Volatile Organic Compounds (VOCs) Data Base update is the result of an ongoing effort to gather, evaluate, and compile the measured concentrations of a large number of VOCs. Data on the observed concentrations of three hundred twenty ...

J. J. Shah L. T. Cupitt

1987-01-01

387

Methods for the Determination of Organic Compounds in Drinking Water, Supplement 1.  

National Technical Information Service (NTIS)

Nine analytical methods covering 54 organic contaminants which may be present in drinking water or drinking water sources are described in detail. Seven of these methods cover compounds designated for regulation under the Safe Drinking Water Act Amendment...

1990-01-01

388

Interlaboratory Study of a Test Method for Measuring Total Volatile Organic Compound Content of Consumer Products.  

National Technical Information Service (NTIS)

Consumer products are potentially significant sources of volatile organic compounds (VOCs), which contribute to formation of ozone in photochemical smog. Currently, the U.S Environmental Protection Agency (EPA) has no approved method for measuring the VOC...

E. E. Rickman G. B. Howe R. K. M. Jayanty

1995-01-01

389

INTERLABORATORY STUDY OF A TEST METHOD FOR MEASURING TOTAL VOLATILE ORGANIC COMPOUND CONTENT OF CONSUMER PRODUCTS  

EPA Science Inventory

The report describes results of an interlaboratory study to estimate repeatability (precision of analyses performed by a single laboratory) and reproducibility (precision analyses performed by different laboratories) of a consumer products volatile organic compound (VOC) measurem...

390

NEUROTOXIC EFFECTS OF CONTROLLED EXPOSURE TO A COMPLEX MIXTURE OF VOLATILE ORGANIC COMPOUNDS  

EPA Science Inventory

Subjective reactions of discomfort, impaired air quality, irritation of mucosal membranes, and impaired memory have been reported in chemically sensitive subjects during exposure to volatile organic compounds (VOC's) found in new buildings. 6 normal healthy male subjects aged 18-...

391

ANALYTICAL REFERENCE STANDARDS AND SUPPLEMENTAL DATA FOR PESTICIDES AND OTHER ORGANIC COMPOUNDS  

EPA Science Inventory

;Contents: List of available pesticide standards and ordering information; Compounds deleted from 1978 stock and name changes; List of non-pesticide organic chemical standards; Safe handling of primary reference standards; Preparation and storage of reference standards; Decoding ...

392

EVALUATION USING AN ORGANOPHILIC CLAY TO CHEMICALLY STABILIZE WASTE CONTAINING ORGANIC COMPOUNDS  

EPA Science Inventory

A modified clay (organophilic) was utilized to evaluate the potential for chemically stabilizing a waste containing organic compounds. hemical bonding between the binder and the contaminants was indicated. eachate testing also indicated strong binding. Copy available at NTIS as ...

393

LITERATURE REVIEW OF PERSONAL AIR MONITORS FOR POTENTIAL USE IN AMBIENT AIR MONITORING OF ORGANIC COMPOUNDS  

EPA Science Inventory

The open literature, Federal publications, industrial reports, and other sources published between 1975 and 1980 were reviewed for information relevant to personal air samplers potentially useful in sampling organic compounds at ambient levels (50-200 ppt). Seventy one references...

394

CONTROL OF INDUSTRIAL VOC (VOLATILE ORGANIC COMPOUND) EMISSIONS BY CATALYTIC INCINERATION. VOLUME 9. QUALITY ASSURANCE  

EPA Science Inventory

Radian Corporation, under contract to the U.S. Environmental Protection Agency, performed site selection, test plan development, and performance tests of catalytic incinerators used for volatile organic compound (VOC) emissions control at industrial sites. VOC emissions are of co...

395

Organic solid state switches incorporating porphyrin compounds and method for producing organic solid state optical switches  

DOEpatents

A light-intensity dependent molecular switch comprised of a compound which shuttles an electron or a plurality of electrons from a plurality of electron donors to an electron acceptor upon being stimulated with light of predetermined wavelengths, said donors selected from porphyrins and other compounds, and a method for making said compound.

Wasielewski, Michael R. (Naperville, IL); Gaines, George L. (River Forest, IL); Niemczyk, Mark P. (Wheaton, IL); Johnson, Douglas G. (Grayslake, IL); Gosztola, David J. (Bolingbrook, IL); O' Neil, Michael P. (San Leandro, CA)

1996-01-01

396

Organic solid state switches incorporating porphyrin compounds and method for producing organic solid state optical switches  

DOEpatents

A light-intensity dependent molecular switch comprised of a compound which shuttles an electron or a plurality of electrons from a plurality of electron donors to an electron acceptor upon being stimulated with light of predetermined wavelengths, said donors selected from porphyrins and other compounds, and a method for making said compound are disclosed. 4 figs.

Wasielewski, M.R.; Gaines, G.L.; Niemczyk, M.P.; Johnson, D.G.; Gosztola, D.J.; O`Neil, M.P.

1996-07-23

397

Gas and particulate-phase specific tracer and toxic organic compounds in environmental tobacco smoke  

Microsoft Academic Search

Cigarette smoke constituents are worthy of concern and characterized as carcinogens. Different experiment conditions may affect the environmental tobacco smoke (ETS) constituents. A study was undertaken in a 75.5-m3 spare office to evaluate ETS constituents in a real environment. Thirty-four volatile organic compounds (VOCs) including three ETS tracers: nicotine, 2,5-dimethylfuran and 3-ethenylpyridine (3-EP), 19 carbonyl compounds, 54 semi-volatile compounds (24

Xinhui Bi; Guoying Sheng; Yanli Feng; Jiamo Fu; Juexin Xie

2005-01-01

398

Determination of volatile organic compounds in emissions by coal-fired power stations from Spain.  

PubMed

This study concerns the emissions of volatile organic compounds (VOCs) by coal fired power stations. The main compounds are monoaromatic hydrocarbons and aliphatic hydrocarbons, chlorinated compounds have less importance. The influence of combustion parameters can not be clearly established. Emissions factors were calculated and they are smaller than those of other anthropogenic combustions. A comparative study of two sources of VOCs, power stations and motor vehicles, indicates that the environmental impact of the latter are most important. PMID:11424734

Fernández-Martínez, G; López-Vilariño, J M; López-Mahía, P; Muniategui-Lorenzo, S; Prada-Rodríguez, D; Fernández-Fernández, E

2001-05-01

399

Solute transport model for trace organic neutral and charged compounds through nanofiltration and reverse osmosis membranes  

Microsoft Academic Search

Rejection of trace organic compounds, including disinfection by-products (DBPs) and pharmaceutical active compounds (PhACs), by high-pressure membranes has become a focus of public interest internationally in both drinking water treatment and wastewater reclamation\\/reuse. The ability to simulate, or even predict, the rejection of these compounds by high-pressure membranes, encompassing nanofiltration (NF) and reverse osmosis (RO), will improve process economics and

Tae-Uk Kim; Jörg E. Drewes; R. Scott Summers; Gary L. Amy

2007-01-01

400

Chemical class separation and characterization of organic compounds in synthetic fuels  

Microsoft Academic Search

A separation method is described for the identification of organic compounds in synthetic fuel products. Prefractionation of crude synfuel materials into discrete chemical classes was prformed by adsorption column chromatography using small quantities of neutral aluminum oxide and silicic acid. Subsequent high-resolution separation of individual components was achieved by using capillary column gas chromatography, and specific compound types were determined

Douglas W. Later; Milton L. Lee; Keith D. Bartle; Robert C. Kong; Daniel L. Vassilaros

1981-01-01

401

Individual organic compounds in water extracts from podzolic soils of the Komi Republic  

NASA Astrophysics Data System (ADS)

The contents of organic compounds in water extracts from organic horizons of loamy soils with different water contents from the medium taiga zone of the Komi Republic were determined by gas-liquid chromatography and chromatography-mass spectrometry. The mass concentration of organic carbon in the extracts was in the range of 290-330 mg/dm3; the mass fraction of the carbon from the identified compounds was 0.5-1.9%. Hydrocarbons made up about 60% of the total identified compounds; acids and their derivatives composed less than 40%. Most of the acids (40-70%) were aliphatic hydroxy acids. The tendencies in the formation of different classes of organic compounds were revealed depending on the degree of the soil hydromorphism. The acid properties of the water-soluble compounds were studied by pK spectroscopy. Five groups of compounds containing acid groups with similar pKa values were revealed. The compounds containing groups with pKa < 4.0 were predominant. The increase in the surface wetting favored the formation of compounds with pKa 3.2-4.0 and 7.4-8.4.

Shamrikova, E. V.; Punegov, V. V.; Gruzdev, I. V.; Vanchikova, E. V.; Vetoshkina, A. A.

2012-10-01

402

Delivery of Complex Organic Compounds from Planetary Nebulae to the Solar System  

Microsoft Academic Search

Infrared spectroscopic observations of planetary nebulae and proto-planetary nebulae have shown that complex organic compounds are synthesized in these objects over periods as short as a thousand years. These compounds are ejected into the interstellar medium and spread throughout the Galaxy. Evidence from meteorites has shown that these stellar grains have reached the Solar System, and may have showered the

Sun Kwok

2009-01-01

403

Barbecue charcoal combustion as a potential source of aromatic volatile organic compounds and carbonyls  

Microsoft Academic Search

The emission concentrations of a number of aromatic volatile organic compounds (VOCs) and carbonyl compounds were quantified during the combustion of commonly used barbecue charcoal. The concentrations of VOC and carbonyls were determined by gas chromatography coupled with thermal desorption and HPLC method, respectively. The analysis of VOC emission concentrations showed that toluene (116±444ppb) was the most abundant. On the

Ehsanul Kabir; Ki-Hyun Kim; Ji-Won Ahn; Jong Ryeul Sohn

2010-01-01

404

Emissions of volatile organic compounds from vegetation and the implications for atmospheric chemistry  

Microsoft Academic Search

Vegetation provides a major source of reactive carbon entering the atmosphere. These compounds play an important role in (1) shaping global tropospheric chemistry, (2) regional photochemical oxidant formation, (3) balancing the global carbon cycle, and (4) production of organic acids which contribute to acidic deposition in rural areas. Present estimates place the total annual global emission of these compounds between

Fred Fehsenfeld; Jack Calvert; Ray Fall; Paul Goldan; A. B. Guenther; C. N. Hewitt; Brian Lamb; Shaw Liu; Michael Trainer; Hal Westberg; Pat Zimmerman

1992-01-01

405

Toxicity of halogenated organic compounds. (Latest citations from the NTIS bibliographic database). Published Search  

SciTech Connect

The bibliography contains citations concerning health and environmental effects of halogenated organic compounds. Topics include laboratory and field investigations regarding bioaccumulation and concentration, metabolic aspects, and specific site studies in industrial and commercial operations. Pesticides, solvents, and a variety of industrial compounds are discussed. (Contains 250 citations and includes a subject term index and title list.)

Not Available

1993-09-01

406

Sorbent-based sampling methods for volatile and semi-volatile organic compounds in air  

Microsoft Academic Search

Sorbent tubes\\/traps are widely used in combination with gas chromatographic (GC) analytical methods to monitor the vapour-phase fraction of organic compounds in air. Target compounds range in volatility from acetylene and freons to phthalates and PCBs and include apolar, polar and reactive species. Airborne vapour concentrations will vary depending on the nature of the location, nearby pollution sources, weather conditions,

Elizabeth Woolfenden

2010-01-01

407

Organic compounds in the flue gas of a hazardous waste incinerator  

Microsoft Academic Search

This study describes organic compounds in the flue gas of a hazardous waste incinerator. Polycyclic and heterocyclic aromatics, phthalate esters, phosphate esters, halogenated benzenes, biphenyls, naphthalenes, phenols as well as nitro compounds were separated by capillary gas chromatography, characterized and quantified by mass spectroscopy.

J. Wienecke; H. Kruse; U. Huckfelct; W. Eickhoff; O. Wassermann

1995-01-01

408

Fabrication of ZnO nanostructures: Effect of organic and inorganic compounds  

Microsoft Academic Search

Varieties of Zinc Oxide nanostructures have been fabricated by a simple wet chemical method. The growth of the nanostructures was also studied with the use of various organic and inorganic compounds. A morphological change from rod-like structure to nanosheets was observed in presence of those compounds. We also observed a preferential growth of the nanostructure when hexamine was used and

P. K. Samanta; S. Basak; P. R. Chaudhuri

2010-01-01

409

Application of the principle of corresponding states to orthobaric densities of organic and inorganic compounds  

Microsoft Academic Search

Most non-associated organic and inorganic compounds are shown to obey the principle of corresponding states with regard to the orthobaric or saturated densities. The compounds are divided into two classes: one class containing those substances which behave like the perfect gases (Ar, Kr, Xe) with respect to this principle; the other consists of all other non-associated species. Each class follows

N van Meurs

1995-01-01

410

Laboratory study of the adsorption of organic and inorganic compounds by coal  

Microsoft Academic Search

A laboratory study of the adsorption of organic and inorganic compounds by coal was conducted by the University of Caifornia Lawrence Livermore Laboratory to elucidate earlier experiments on ground-water contamination by underground coal gasification. In those studies, there was a continuous decrease in the concentrations of all pollutants, including phenolic compounds, aromatic hydrocarons, cyanide and metal ions (e.g., Ni, Zn,

1979-01-01

411

RADIOACTIVATION ANALYSIS OF BROMINE AND IODINE IN ORGANIC COMPOUNDS USING A LOW-LEVEL NEUTRON SOURCE  

Microsoft Academic Search

Some experimental results are given for the activation analysis of Br ; and I in organic compounds using a Ra-Be neutron source. The sample was ; dissolved in a solvent, adjusted to constant volume, and irradiated. The results ; are tabulated for a large number of compounds. Although the sensitivity is low, ; the results are satisfactory. (D.L.C.);

Haruo Tsuji; Yuzuru Kusaka; Yasuo Namikawa

1962-01-01

412

Source Apportionment of Ambient Volatile Organic Compounds in Bursa, a Heavily Industrialized City in Turkey  

Microsoft Academic Search

Weekly passive sampling campaigns were carried out over two sample periods to measure volatile organic compounds (VOCs) in Bursa, one of the most heavily industrialized cities in Turkey. The measurements, taken at 40 points in October 2005 and 49 points in April 2006, revealed concentrations of 34 VOCs, including aromatics, olefins, paraffin and halogenated compounds; with benzene, toluene, ethylbenzene, and

Mihriban Yilmaz Civan; Öznur O?uz Kuntasal; Gürdal Tuncel

2011-01-01

413

Volatile Organic Compounds in Ground Water From Rural Private Wells, 1986 to 1999  

Microsoft Academic Search

The U.S. Geological Survey (USGS) collected or compiled data on volatile organic compounds (VOCs) in samples of untreated ground water from 1,926 rural private wells during 1986 to 1999. At least one VOC was detected in 12 percent of samples from rural private wells. Individual VOCs were not commonly detected with the seven most frequently detected compounds found in only

Michael J. Moran; Wayne W. Lapham; Barbara L. Rowe; John S. Zogorski

2004-01-01

414

Volatile chlorinated organic compound levels in rain water from Kobe City in Japan  

Microsoft Academic Search

Water pollution by volatile chlorinated organic compounds has become a serious environmental problem. The Environmental Agency of Japan has defined the regulations on trichloroethylene, tetrachloroethylene, 1,1,1-trichloroethane and carbon tetrachloride in wastewater in 1989. In order to protect against water pollution, it is important to keep concentrations in these compounds in environmental water as low as possible. Therefore, the determination of

Atsuko Adachi; Tadashi Kobayashi

1994-01-01

415

Volatile organic compound emissions in relation to plant carbon fixation and the terrestrial carbon budget  

Microsoft Academic Search

A substantial amount of carbon is emitted by terrestrial vegetation as biogenic volatile organic compounds (VOC), which contributes to the oxidative capacity of the atmosphere, to particle production and to the carbon cycle. With regard to the carbon budget of the terrestrial biosphere, a release of these carbon compounds is regarded as a loss of photosynthetically fixed carbon. The significance

Jürgen Kesselmeier; Paolo Ciccioli; Uwe Kuhn; Paolo Stefani; Thomas Biesenthal; Stefanie Rottenberger; Annette Wolf; Marina Vitullo; Ricardo Valentini; Antonio Nobre; Pavel Kabat; Meinrat O. Andreae

2002-01-01

416

TEMPERATURE-DEPENDENT COLLECTION EFFICIENCY OF A CRYOGENIC TRAP FOR TRACE-LEVEL VOLATILE ORGANIC COMPOUNDS  

EPA Science Inventory

Reduced temperature preconcentration of volatile organic compounds in a packed trap is examined experimentally as a function of trapping temperatures ranging from -180C to +100C. Trapped compounds are thermally desorbed into a capillary column-equipped gas chromatograph and quant...

417

Heterogeneous Photocatalysis for Control of Volatile Organic Compounds in Indoor Air  

Microsoft Academic Search

Research results concerning the photocatalytic activity and selectivity of benzene are discussed. This compound, which represents one of an important class of volatile organic compounds found in indoor air, was oxidized in an annular photocatalytic reactor featuring a thin film of titanium dioxide and illuminated by a fluorescent black light. The gas phase products, carbon dioxide and carbon monoxide, were

William A. Jacoby; Daniel M Blake; John A. Penned; James E. Boulter; LeAnn M. Vargo; Marya C George; Suzanne K. Dolberg

1996-01-01

418

Removal of organic compounds by a biofilm supported on GAC: modelling of batch and column data  

Microsoft Academic Search

The performance of a biofilm of Arthrobacter viscosus supported on granular activated carbon on the retention of organic compounds was evaluated. The presence of functional groups\\u000a on the cell wall surface of the biomass that may interact with the organic compounds was confirmed by Fourier transform infrared\\u000a spectroscopy, to assess the applicability of this system to the removal of those

Cristina Quintelas; Bruna Silva; Hugo Figueiredo; Teresa Tavares

2010-01-01

419

Guideline series: Control of volatile organic compound emissions from offset lithographic printing. Draft report  

SciTech Connect

The report is a draft control techniques guideline (CTG) document for control of volatile organic compound emissions from offset lithographic printing. The document address sheet fed, non-heatset web, newspapers, and heat-set web offset lithographic printing. The principle emission sources addressed are fountain solution, cleaning solvents (blanket and roller washes) and heatset dryers. The purpose of a CTG document is to assist state and local air pollution agencies in developing regulations to limit emissions of volatile organic compounds.

NONE

1993-09-01

420

Volatile organic compounds and particulates as components of diesel engine exhaust gas  

Microsoft Academic Search

Volatile organic compounds (VOC) and soot particles have been determined in a Diesel’s exhaust gas. A new sampling method allowed the measurement of emissions of organic compounds (C1 to C20) in a gas chromatogram at a detection limit of ca. 0.2 mg\\/m3. Particles were collected with a filter bed of ceramic particles and characterized by temperature programmed desorption (TPD) and

Hans Schulz; Gilberto Bandeira De Melo; Farid Ousmanov

1999-01-01

421

Structure-property relationship between half-wave potentials of organic compounds and their topology  

Microsoft Academic Search

A significant correlation was found between half-wave potentials of organic compounds and their topological indices, Ax1, Ax2, and Ax3. The simplicity of calculation of the index from the connectivity in the molecular skeleton, together with the significant correlation, indicates its practical value. Good results have been obtained by using them to predict the half-wave potentials of some organic compounds.

Hua Li; Lu Xu; Qiang Su

1995-01-01

422

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

SciTech Connect

The theoretical potential for the formation of clusters of vapor-phase organic compounds found in indoor air around the [sup 218]PoO[sub x][sup +] ion was investigated as well as which compounds were most likely to form clusters. A compilation of measurements of indoor organic compounds has been made for future experiments and theoretical calculations by the radon research community. Forty-four volatile and semivolatile organic compounds out of the more than 300 that 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 [sup 218]PoO[sub x][sup +] 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 semivolatile organic compounds (pentachlorophenol, nicotine, chlordane, chlorpyrifos). Although the estimated diameters are consistent with the measured diameters for the unattached fraction, the state of experimental and theoretical knowledge in this area is not sufficiently developed to judge the quantitative validity of these predictions. 48 refs., 1 fig., 5 tabs.

Daisey, J.M. (Lawrence Berkeley Lab., CA (United States)); Hopke, P.K. (Clarkson Univ., Potsdam, NY (United States))

1993-07-01

423

Examination of organic compounds from insoluble organic matter isolated from some Antarctic carbonaceous chondrites by heating experiments  

NASA Astrophysics Data System (ADS)

Insoluble organic matter isolated from five Antarctic CM2 chondrites was heated in a thermal analyzer from room temperature to 800 C under helium atmosphere. Organic compounds from the thermal decomposition of the Yamato-791198 sample were studied by a gas chromatograph-mass spectrometer (GC-MS). The number of compounds identified was over 120, belonging mainly to the two following groups: (1) benzene and naphthalene, and their alkyl derivatives; and (2) sulfur-containing heterocycles and their alkyl derivatives. Small amounts of aliphatic hydrocarbons and nitriles were also detected. Relative amounts of compounds released from the five chondrite samples were monitored by the MS with increasing temperature. Yamato-74662 and Yamato-791198 showed organic compounds mainly over the temperature range of 300-600 C, while the other three (Yamato-793321, Yamato-86720, and Belgica-7904) did not show any, except small amounts of benzene. These results indicate that the insoluble organics in Yamato-74662 and Yamato-791198 possess a thermally labile organic fraction, whereas those in Yamato-793321, Yamato-86720, and Belgica-7904 do not and are graphitic. The difference between the insoluble organic fractions may be related to aqueous alteration and thermal metamorphism on the parent bodies.

Komiya, M.; Shimoyama, A.; Harada, K.

1993-02-01

424

Laboratory and field screening strategies for measuring volatile organic compounds in landfill gas  

SciTech Connect

Distinct patterns often exist in the presence and absence of hazardous contaminants in the environment. These patterns can be used to select efficient screening tools, or groups of compounds that provide the most information on overall occurrences of a larger target group of compounds. By using these screens to indicate whether a sample is contaminated with detectable amounts of the compounds of interest, attention can be focused on those samples considered most likely to contain measurable concentrations of targeted compounds. The cost savings that result from eliminating samples that are most likely uncontaminated can be applied to obtaining additional samples that more accurately characterize the spatial or temporal variability of the environmental problem. In a retrospective application of screening techniques to the State of California's database of volatile organic compounds in landfill gas, two laboratory screening compounds, perchloroethylene and methylene chloride, represent over 95% of the total number of positive detections of a target group of 10 volatile organic compounds. Benzene and vinyl chloride, two field screening compounds that were selected using the characteristics of commercially available colorimetric detector tubes, recorded 74% of the total contaminant detections and a 52% savings in analytical costs as compared to an exhaustive analysis of every sample for all 10 volatile organic compounds. The number of detections recorded could have been improved if more sensitive and less selective field screening devices were available.

Emerson, C.W.

1999-11-01

425

Volatile organic compounds at a coastal site. 1. Seasonal variations  

SciTech Connect

Alkylaromatics, alkanes, aldehydes, dimethyl polysulfides, and miscellaneous compounds were determined over a 15-month period at a coastal site. Alkylbenzenes appear dominated by anthropogenic inputs and air-sea exchange, with selective biodegradation showing minor effects in the summer. Offshore mixing and adsorption to sediments seems minor. Alkylnaphthalenes showed a contrasting pattern, best explained by a dominant wintertime source such as space heating oil use. Alkanes were frequently petroleum derived, but pentadecane, heptadecane, and pristane showed evidence of strong biogenic sources as well. The aldehydes exhibited complex behavior, with evidence for autooxidative as well as plankton sources. The dimethyl polysulfides had great variability; they may contribute significant sea-to-air sulfur fluxes if our measured levels are typical of the larger coastal region. An incompletely identified octatriene occurs briefly; it may be an algal product related to the pheromone ''fucoserraten''.

Gschwend, P.M.; Zafiriou, O.C.; Mantoura, R.F.C.; Schwarzenbach, R.P.; Gagosian, R.B.

1982-01-01

426

Cyclodextrin-based chemical microsensors for Volatile Organic Compounds (VOCs)  

SciTech Connect

This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). This project addressed the development of surface-acoustic-wave (SAW)-based chemical sensors for remote, real-time sensing in air, groundwater, and possibly soil, of chlorinated and aromatic hydrocarbons using innovative molecular self-assembly techniques. Our goal is parts per billion (ppb) sensitivity to specific aromatic and chlorinated hydrocarbons using cyclodextrin as the selective layer of a SAW-based mass sensor. We have demonstrated that SAW sensors can differentiate between compounds with similar composition, structure, and polarity. These efforts, however, can be enhanced by using sensor arrays and smart data processing systems. Secondly, ionic interactions provide a convenient way to fabricate thin films for sensor applications. The potential of these thin films for sensor applications is currently being evaluated. 3 figs.

Li, DeQuan

1998-12-31

427

Interactions of aqueous metal ions with organic compounds found in coal gasification: model systems  

SciTech Connect

The interaction of metal ions with organic compounds indigenous to coal gasification materials was studied in a model system. Aqueous solutions of FeT , CuS and NiS in contact with mixtures of selected organic compounds were examined by using chromatographic and spectroscopic techniques. Aqueous FeT ions and, to a lesser extent, CuS ions extract organic compounds from the nonaqueous layer and associate with these organic molecules in aqueous solution. Quantitative aspects of the extraction process were measured by gas chromatographic methods, while spectroscopic measurements were used to characterize the association between metal ions and organic molecules. The interaction of the metal ion solutions was compared to that of buffers of similar pH. The behavior of both the iron and copper ion solutions differed from that of the buffers.

Jorgensen, A.D.; Stetter, J.R.; Stamoudis, V.C.

1985-10-01

428

Effects of additional nonmethane volatile organic compounds, organic nitrates, and direct emissions of oxygenated organic species on global tropospheric chemistry  

NASA Astrophysics Data System (ADS)

This work evaluates the sensitivity of tropospheric ozone and its precursors to the representation of nonmethane volatile organic compounds (NMVOCs) and organic nitrates. A global 3-D tropospheric chemistry/transport model (IMPACT) has been exercised initially using the GEOS-Chem chemical reaction mechanism. The model was then extended by adding emissions and photochemical reactions for aromatic and terpenoid hydrocarbons, and by adding explicit representation of hydroxy alkyl nitrates produced from isoprene. Emissions of methanol, phenol, acetic acid and formic acid associated with biomass burning were also added. Results show that O3 increases by 20% in most of the troposphere, peroxyacetyl nitrate (PAN) increases by 30% over much of the troposphere and OH increases by 10%. NOx (NO + NO2) decreases near source regions and increases in remote locations, reflecting increased transport of NOx away from source regions by organic nitrates. The increase in O3 was driven largely by the increased role of PAN as a transporter of NOx and by the rerelease of NOx from isoprene nitrates. The increased PAN production was associated with increases in methyl glyoxal and hydroxyacetone. Comparison with measured values show reasonable agreement for O3 and PAN, but model measurement agreement does not either improve or degrade in the extended model. The extended model shows improved agreement with measurements for methanol, acetic acid and peroxypropional nitrate (PPN). Results from the extended model were consistent with measured alkyl nitrates and glycolaldehyde, but hydroxyacetone and methyl glyoxal were overestimated. The latter suggests that the effect of the isoprene nitrates is somewhat smaller than estimated here. Although the model measurement comparison does not show specific improvements with the extended model, it provides a more complete description of tropospheric chemistry that we believe is important to include.

Ito, Akinori; Sillman, Sanford; Penner, Joyce E.

2007-03-01

429

Transformations of Model Organic Compounds on Snow Grains at Summit, Greenland  

NASA Astrophysics Data System (ADS)

Photochemical reactions in snowpacks produce a number of chemicals species that can significantly impact the overlying atmosphere and transform many organic pollutants. During this past summer's field season at Summit we examined the kinetics for the disappearance of a suite of model organic compounds in surface snowpack. Our compounds (2-nitrobenzaldehyde, sodium benzoate, syringol, 4-chlorophenol, 2-oxo-butanoic acid, and phenanthrene) were chosen because they represent markers from several different emission sources and because they have a range of expected fates, i.e., their lifetimes will be determined by different processes. These processes include direct photolysis and reactions with oxidants such as hydroxyl radical (OH) and singlet molecular oxygen (1O2*) In addition to measuring the rates of loss of the model organics, we also measured concentrations of OH and 1O2* in the snow samples, as well as rates of direct photolysis of the organics in frozen, purified water. Our goal was to compare the measured lifetimes of the organic compounds with calculated lifetimes based on reactions with OH and 1O2* and direct photolysis. While certain compounds behaved as expected, others decayed more slowly, or more rapidly, than expected, indicating that other, unidentified, snow grain reactions and/or mechanisms are significant. The rates of organic compound loss, the potential reasons for the observed differences, and the implications for lifetimes of trace organic pollutants in polar regions will be discussed.

Galbavy, E. S.; Ram, K.; Anastasio, C.

2005-12-01

430

Distribution and biological turnover of dissolved organic compounds in the water column of the Black Sea  

NASA Astrophysics Data System (ADS)

Water column concentrations and turnover rates were determined for a suite of low molecular weight organic compounds in the Black Sea. The classes of compounds studied included amino acids, simple sugars, ?-keto acids, aldehydes, ketones, carboxylic acids, flavins and thiols. Our study yielded some new insights, as well as a few surprising discoveries, regarding the composition and cycling of organic matter in the Black Sea. (1) Uptake rates of organic compounds were from 2 to 4640 times faster in oxic surface waters than in anoxic waters. (2) Sharp maxima or minima in concentrations of organic compounds coincided with zones of enhanced microbial activities, especially in the vicinity of the oxic-suboxic and suboxic-anoxic interfaces. (3) The benthic boundary layer, 300-400 m thick, had a markedly different organic composition and substantially higher concentrations of organic acids, and to a lesser extent sugars and thiols, than the overlying water. (4) A dramatic change in the composition and concentration of dissolved free amino acids occurred in the water column during the cruise and appeared to be related to biological patchiness. (5) Organic thiols constituted a significant portion (e.g. 10-20%) of the total reduced sulfur near the top of the sulfidic zone, and may contribute to the origin of hydrogen sulfide in this zone. (6) Major unknown amine and carbonyl compounds were discovered in the anoxic zone, providing evidence that the Black Sea contains unique anaerobic bacteria with possibly new biochemical pathways.

Mopper, Kenneth; Kieber, David J.

431

Study of two-photon excitation spectra of organic compounds absorbing in the UV region  

SciTech Connect

A method is proposed for recording two-photon excitation (TPE) spectra of organic compounds with the help of picosecond pulses from a dye laser tunable in the range from 550 to 640 nm. The TPE spectra are obtained for organic scintillators and drugs: paraterphenyl in liquid and solid phases, stilbene single crystal and Streptocid powder, having a one-photon absorption band in the region from 270 to 350 nm. It is shown that the vibronic structure in the TPE spectra of these compounds is independent of their aggregate state and is an individual characteristic of each of the compounds. (active media)

Babenko, V A; Sychev, Andrei A [P.N. Lebedev Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

2004-12-31

432

Deuterium enrichment by selective photo-induced dissociation of an organic carbonyl compound  

DOEpatents

A method for producing a deuterium enriched material by photoinduced dissociation which uses as the working material a gas phase photolytically dissociable organic carbonyl compound containing at least one hydrogen atom bonded to an atom which is adjacent to a carbonyl group and consisting of molecules wherein said hydrogen atom is present as deuterium and molecules wherein said hydrogen atom is present as another isotope of hydrogen. The organic carbonyl compound is subjected to intense infrared radiation at a preselected wavelength to selectively excite and thereby induce dissociation of the deuterium containing species to yield a deuterium enriched stable molecular product. Undissociated carbonyl compound, depleted in deuterium, is preferably redeuterated for reuse.

Marling, John B. (Livermore, CA)

1981-01-01

433

Studies on volatile organic compounds of Tuber borchii and T. asa-foetida.  

PubMed

Ascomata of two truffle species, Tuber borchii and T. asa-foetida, both naturally growing in woodlands of the Basilicata region (southern Italy), were identified on the basis of ascospore morphology and compared under a volatile organic compound profile to determine the particular volatile organic compounds that characterize each taxon. Solid-phase microextraction-gas chromatography-mass spectrometry analysis of the samples showed the presence of 1-methyl-1,3-butadiene as a primary component in both truffles. T. asa-foetida showed a compound, toluene, not present in T. borchii, which creates the penetrating "solvent" smell of the truffle. PMID:22685100

D'Auria, Maurizio; Rana, Gian Luigi; Racioppi, Rocco; Laurita, Alessandro

2012-06-08

434

Exposure to Volatile Organic Compounds and Possibility of Exposure to By-product Volatile Organic Compounds in Photolithography Processes in Semiconductor Manufacturing Factories  

PubMed Central

Objectives The purpose of this study was to measure the concentration of volatile organic compound (VOC)s originated from the chemicals used and/or derived from the original parental chemicals in the photolithography processes of semiconductor manufacturing factories. Methods A total of four photolithography processes in 4 Fabs at three different semiconductor manufacturing factories in Korea were selected for this study. This study investigated the types of chemicals used and generated during the photolithography process of each Fab, and the concentration levels of VOCs for each Fab. Results A variety of organic compounds such as ketone, alcohol, and acetate compounds as well as aromatic compounds were used as solvents and developing agents in the processes. Also, the generation of by-products, such as toluene and phenol, was identified through a thermal decomposition experiment performed on a photoresist. The VOC concentration levels in the processes were lower than 5% of the threshold limit value (TLV)s. However, the air contaminated with chemical substances generated during the processes was re-circulated through the ventilation system, thereby affecting the airborne VOC concentrations in the photolithography processes. Conclusion Tens of organic compounds were being used in the photolithography processes, though the types of chemical used varied with the factory. Also, by-products, such as aromatic compounds, could be generated during photoresist patterning by exposure to light. Although the airborne VOC concentrations resulting from the processes were lower than 5% of the TLVs, employees still could be exposed directly or indirectly to various types of VOCs.

Shin, Jung-Ah; Park, Hyun-Hee; Yi, Gwang Yong; Chung, Kwang-Jae; Park, Hae-Dong; Kim, Kab-Bae; Lee, In-Seop

2011-01-01

435

Sorption of organic compounds in the aqueous phase onto tire rubber  

SciTech Connect

Batch sorption tests were conducted to investigate the sorption capacity of organic compounds by ground tire and to assess the effects of the presence of other organic compounds, ionic strength, pH, ground tire particle size, and temperature on sorption. None of the factors were significant under the conditions tested, m-Xylene had the highest partition coefficient, followed by ethylbenzene, toluene, trichloroethylene, 1,1,1-trichloroethane, chloroform, and methylene chloride (13 L/kg). The partition coefficients had a logarithmic linear relationship with the octanol-water partition coefficients. The diffusion coefficients of the compounds tested were in the range of 10{sup {minus}8} cm{sup 2}/s. The diffusion coefficients did not correlate well with the physical/chemical properties, such as molecular size, of the compounds tested. The heat of solutions of the compounds tested had relatively low values. Thus, the sorption may not be affected significantly by temperature change. Organic compounds sorbed onto tire rubber appear to be sorbed primarily onto tire rubber polymeric materials and partially carbon black in the tire rubber. Overall, ground tire shows significant capacity as a sorbent of organic compounds.

Kim, J.Y.; Park, J.K.; Edil, T.B. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Civil and Environmental Engineering

1997-09-01

436

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

NASA Astrophysics Data System (ADS)

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.

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

2012-08-01

437

Fenton degradation of organic compounds promoted by dyes under visible irradiation.  

PubMed

The influence of dyes on the Fenton reaction of organic compounds under visible irradiation (lambda > 450 nm) was examined. It was found that the presence of dyes could accelerate greatly the Fenton reaction of organic compounds such as salicylic acid, sodium benzenesulfonate, benzyltrimethylammonium chloride, and trichloroacetic acid under visible irradiation and that a complete mineralization of those compounds could also be achieved. The dyes such as Alizarin Violet 3B which has an anthraquinone structure unit showed much more significant effect on the reaction than the dyes such as malachite green without the quinone unit. A reaction mechanism of dye AV as a cocatalyst in the photo-Fenton reaction of organic compounds under visible irradiation is proposed based on the cycle of Fe(3+)/Fe(2+) catalyzed by quinone species and an electron transfer from the excited dye molecule to Fe3+. PMID:16124319

Ma, Jiahai; Song, Wenjing; Chen, Chuncheng; Ma, Wanhong; Zhao, Jincai; Tang, Yalin

2005-08-01

438

Ion-trap detection of volatile organic compounds in alveolar breath  

SciTech Connect

We describe a method for the collection and microanalysis of the volatile organic compounds in human breath. A transportable apparatus supplies subjects with purified air and samples their alveolar breath; the volatile organic compounds are captured in an adsorptive trap containing activated carbon and molecular sieve. The sample is thermally desorbed from the trap in an automated microprocessor-controlled device, concentrated by two-stage cryofocusing, and assayed by gas chromatography with ion-trap detection. Compounds are identified by reference to a computer-based library of mass spectra with subtraction of the background components present in the inspired air. We used this device to study 10 normal subjects and determined the relative abundance of the volatile organic compounds in their alveolar breath. The breath-collecting apparatus was convenient to operate and was well tolerated by human volunteers.

Phillips, M.; Greenberg, J. (Department of Medicine, St. Vincent's Medical Center of Richmond, Staten Island, NY (United States))

1992-01-01

439

Catalytic Hydrogenation of Organic Compounds without H2 Supply: An Electrochemical System  

ERIC Educational Resources Information Center

|An experiment developed for an undergraduate organic chemistry laboratory course that can be used to introduce the catalytic hydrogenation reaction, catalysis electrochemical principles and gas chromatography is presented. The organic compounds hydrogenated by the electrocatalytic hydrogenation (ECH) process were styrene, benzaldehyde and…

Navarro, Daniela Maria do Amaral Ferraz; Navarro, Marcelo

2004-01-01

440

Microbial community related to volatile organic compound (VOC) emission in household biowaste  

Microsoft Academic Search

Summary Malodorous emissions and potentially pathogenic microorganisms which develop during domestic organic waste collection are not only a nuisance but may also pose health risks. The aim of the present study was to determine whether the presence of spe- cific microorganisms in biowastes is directly related to the composition of the emitted volatile organic compounds (VOCs). The succession of microbial

Sabine Mayrhofer; Tomas Mikoviny; Sebastian Waldhuber; Andreas O. Wagner; Gerd Innerebner; Ingrid H. Franke-Whittle; Tilman D. Märk; Armin Hansel; Heribert Insam

2006-01-01

441

Partial nitrification in a SHARON reactor in the presence of salts and organic carbon compounds  

Microsoft Academic Search

Partial nitrification of ammonia to nitrite was studied as a shortcut process to reduce the oxygen consumption during nitrification and the necessities of organic carbon compounds for denitrification in wastewater treatment plants (WWTP). This process is specially recommended for the treatment of wastewater containing low total organic carbon to nitrogen ratios (C\\/N) like the effluents of anaerobic digesters from the

A. Mosquera-Corral; F. González; J. L. Campos; R. Méndez

2005-01-01

442

Evaluation of the walkthrough survey method for detection of volatile organic compound leaks. Final report  

Microsoft Academic Search

During 1978 and 1979, the Emission Standards and Engineering Division of EPA's Office of Air Quality Planning and Standards conducted a fugitive volatile organic compound (VOC) emission sampling program in organic chemical manufacturing plants and petroleum refineries. As a part of their sampling program, several 'walkthrough surveys,' also called 'unit area surveys,' were conducted. The assistance of EPA's Industrial Environmental

R. C. Weber; K. Mims

1981-01-01

443

Interaction of organic compounds with calcium carbonate--I. Association phenomena and geochemical implications  

Microsoft Academic Search

Stearic acid and albumin dissolved in distilled water, as well as lipoid and amino acid-containing substances dissolved in seawater, interact with carbonate mineral surfaces. In seawater, these compounds represent 14 per cent of the total dissolved organic carbon which is removed from solution by adsorption processes onto carbonate minerals. The mineral surfaces are saturated with organic carbon after adsorbing 0.1

Erwin Suess

1970-01-01

444

Hygroscopic properties of levoglucosan and related organic compounds characteristic to biomass burning aerosol particles  

Microsoft Academic Search

Biomass burning, which is characterized by pyrolysis as well as vaporization and condensation of biomass constituents, is a significant source of atmospheric organic aerosols. In this study, hygroscopic properties of five organic compounds (levoglucosan, D-glucose, and vanillic, syringic, and 4-hydroxybenozoic acids), which are major pyrolysis products of wood, were measured using a tandem differential mobility analyzer. Levoglucosan, which is typically

Michihiro Mochida; Kimitaka Kawamura

2004-01-01

445

TECHNICAL ASSISTANCE DOCUMENT FOR SAMPLING AND ANALYSIS OF TOXIC ORGANIC COMPOUNDS IN AMBIENT AIR  

EPA Science Inventory

The guidance document was originally issued in June 1983. ince then significant changes have occurred in the regulations that cover volatile and semivolatile organic air pollutants. There have also been significant advances in the collection and analysis of organic compounds and ...

446

The search for organic substances and inorganic volatile compounds in the surface of Mars  

Microsoft Academic Search

A total of four Martian samples, one surface and one subsurface sample at each of the two Viking landing sites, Chryse Planitia and Utopia Planitia, have been analyzed for organic compounds by a gas chromatograph-mass spectrometer. In none of these experiments could organic material of Martian origin be detected at detection limits generally of the order of parts per billion

K. Biemann; J. Oro; P. Toulmin III; L. E. Orgel; A. O. Nier; D. M. Anderson; D. Flory; A. V. Diaz; D. R. Rushneck; P. G. Simmonds; J. E. Biller; A. L. Lafleur

1977-01-01

447

Evolution and Kinetics of Volatile Organic Compounds Generated during Low-Temperature Polymer Degradation  

Microsoft Academic Search

A method using direct flame ionization detector (FID) measurement was developed to study total volatile organic compound (VOC) emissions during thermal degradation of polymers. This method was used to estimate organic emissions from different polymers, such as low-density polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and commingled postconsumer streams, such as recycled carpet residue and auto shredder residue (ASR). The

Qin Xiang; Somenath Mitra; Marino Xanthos; Subir K. Dey

2002-01-01

448

EXPERIMENTAL DEVELOPMENT OF THE MASTER ANALYTICAL SCHEME FOR ORGANIC COMPOUNDS IN WATER: PART 2. APPENDICES  

EPA Science Inventory

The Master Analytical Scheme (MAS) for Organic Compounds in Water provides for analysis of purgeable and extractable, as well as neutral and ionic-water-soluble, organics in surface and drinking water and in leachates and various effluents. This report describes experiments in th...

449

Use of sonication for in-well softening of semivolatile organic compounds. 1998 annual progress report  

SciTech Connect

'This project investigates the in-situ degradation of semivolatile organic compounds (SVOCs) and volatile organic compounds (VOCs) using in-well sonication, in-well vapor stripping, and biodegradation. The project has the primary objectives of developing this integrated system for efficient and economical removal and degradation of SVOCs and VOCs from groundwater. The project has as its goal the partial degradation (softening) of the more recalcitrant organic compounds in order to convert them into compounds that are more amenable to both air sparging and biological treatment. By performing the softening in-well, the treated organics can be reinjected and percolated through the subsurface, thereby enhancing biodegradation by generating organics that are more easily biodegraded. This report summarizes work after nearly 2 years of a 3-year project. Argonne National Laboratory is developing a new technology that combines in-well sonication, in-well vapor stripping, and in-situ biodegradation for removal of SVOCs and VOCs from solution. Bench-scale batch experiments have been performed investigating the separate treatment systems involving stripping and sonication of halogenated organics in groundwater, along with the combined sonication/stripping system. Organic contaminants studied include: trichloroethylene (TCE), carbon tetrachloride (CCl4 ), tetrachloroethylene (PCE), trichloroethane (TCA), and ethylene dibromide (EDB). Initial organic concentrations range from {approximately}10 to {approximately}100 mg/L. Results of the sonication and vapor stripping experiments are available upon request.'

Peters, R.W.; Manning, J.F. [Argonne National Lab., IL (US); Hoffmann, M.R. [California Inst. of Tech., Pasadena, CA (US); Gorelick, S. [Stanford Univ., CA (US)

1998-06-01

450

Catalytic Hydrogenation of Organic Compounds without H2 Supply: An Electrochemical System  

ERIC Educational Resources Information Center

An experiment developed for an undergraduate organic chemistry laboratory course that can be used to introduce the catalytic hydrogenation reaction, catalysis electrochemical principles and gas chromatography is presented. The organic compounds hydrogenated by the electrocatalytic hydrogenation (ECH) process were styrene, benzaldehyde and…

Navarro, Daniela Maria do Amaral Ferraz; Navarro, Marcelo

2004-01-01

451

Effects of pesticides and related organic compounds in the sea  

NASA Astrophysics Data System (ADS)

The majority of organic chemicals identified so far in the sea are pesticides and products of technical use; most contain chlorine. Only a limited amount of the actual pollutant load is detectable because few data for “unconventional ” pollutants are available. In view of the considerable structural variety of the large number of chemicals produced, there is a need for prediction measurements of bioconcentration and toxic effects. Physico-chemical data may be used for predicting bioconcentration and life-cycle toxicity tests for the estimation of safe levels. The degree of biomagnification via food chains increases with half lives of the pollutants. When comparing pollutant concentrations with toxicological data it becomes apparent that estuaries and coastal areas deserve special concern, whereas pollutant levels of open ocean waters are unlikely to endanger marine life at present.

Ernst, W.

1980-03-01

452

Henry`s law constant for selected volatile organic compounds in high-boiling oils  

SciTech Connect

Absorption systems are often used to remove and recover organic vapors from process air/gas streams. A high boiling and inert liquid like silicone oil is an excellent absorbent for volatile organic compounds in air. Henry`s law constants of four different volatile organic compounds, namely, acetone, methanol, methylene chloride, and toluene between air and high-boiling oils were determined experimentally by the headspace-GC technique over a temperature range. The Henry`s law constants were fitted as a function of temperature to an equation.

Poddar, T.K.; Sirkar, K.K. [New Jersey Inst. of Tech., Newark, NJ (United States). Dept. of Chemical Engineering, Chemistry and Environmental Science

1996-11-01

453

Factors affecting bioabsorption, metabolism, and storage of organic compounds by aquatic biota  

SciTech Connect

Biological concentration and transfer of organic chemicals through aquatic food webs can be influenced by a variety of environmental, biological, and biochemical factors. Bioaccumulation can be significantly altered by the presence of suspended matter or complex organic mixtures in the water column. In addition, the bioaccumulation factor of a compound is dependent on the species of an organism, its life stage, and the available food supply. Metabolic changes in structure of absorbed organics can alter both the rate and the mechanism of absorption and elimination of organics. In the case of quinoline absorption by trout, both the rate of absorption and the metabolic disposition depended upon whether exposure was through ingestion or through direct water column exposure. All of these factors can be used to explain why the physical properties of organic compounds (most notably octanol/water partition coefficients) are unreliable predictors of bioaccumulation potential. 24 refs., 1 tab.

Bean, R.M.; Dauble, D.D.; Thomas, B.L.; Hanf, R.W.; Chess, E.K.

1985-12-01

454

(Semi)volatile Organic Compounds and Microbiological Entities in Snow during OASIS Barrow 2009  

NASA Astrophysics Data System (ADS)

Snow has recently been shown to be 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). Additional grab samples were taken for analysis of non-methane hydrocarbons in air. Moreover we analyzed for microbial species in air and snow. Identifed organic compounds covered a wide range of functionalities and molecular weights, 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 implications of the results for organic snow chemistry.

Kos, G.; Nafissa, A.; Lutchman, D.; Mortazavi, R.; Ariya, P.

2009-12-01

455

Kinetics of the electrochemical oxidation of organic compounds at BDD anodes: modelling of surface reactions  

Microsoft Academic Search

This paper presents the results of a numerical study of the kinetics of electrochemical oxidation of different organic substances\\u000a at boron doped diamond (BDD).\\u000a \\u000a It is well established that oxidation of organics at BDD anodes takes place in the potential region of oxygen evolution, through\\u000a reaction steps in which OH radicals are involved: these radicals can react with organic compounds

Michele Mascia; Annalisa Vacca; Simonetta Palmas; Anna Maria Polcaro

2007-01-01

456

Development of technology performance specifications for volatile organic compounds  

SciTech Connect

The Office of Technology Development (OTD) within the Office of Environmental Restoration and Waste Management of the Department of Energy has a mission to deliver needed and usable technologies to its customers. The primary customers are individuals and organizations performing environmental characterization and remediation, waste cleanup, and pollution prevention at DOE sites. DOE faces a monumental task in cleaning up the dozen or so major sites and hundreds of smaller sites that were or are used to produce the US nuclear weapons arsenal and to develop nuclear technologies for national defense and for peaceful purposes. Contaminants and waste materials include the radionuclides associated with nuclear weapons, such as plutonium and tritium, and more common pollutants and wastes of industrial activity such as chromium, chlorinated solvents, and polychlorinated biphenyls (PCBs). Quite frequently hazardous wastes regulated by the Environmental Protection Agency are co-mingled with radioactive wastes regulated by the Nuclear Regulatory Commission to yield a [open quotes]mixed waste,[close quotes] which increases the cleanup challenges from several perspectives. To help OTD and its investigators meet DOE's cleanup goal, technology performance specifications are being implemented for research and development and DT E projects. Technology performance specifications or [open quotes]performance goals[close quotes] describe, quantitatively where possible, the technology development needs being addressed. These specifications are used to establish milestones, evaluate the status of ongoing projects, and determine the success of completed projects.

Purdy, C.; Schutte, W.E. (Dept. of Energy, Germantown, MD (United States)); Erickson, M.D.; Carpenter, S.C.; Doskey, P.V.; Lindahl, P.C.; Pflug, A.D. (Argonne National Lab., IL (United States))

1993-01-01

457

Development of technology performance specifications for volatile organic compounds  

SciTech Connect

The Office of Technology Development (OTD) within the Office of Environmental Restoration and Waste Management of the Department of Energy has a mission to deliver needed and usable technologies to its customers. The primary customers are individuals and organizations performing environmental characterization and remediation, waste cleanup, and pollution prevention at DOE sites. DOE faces a monumental task in cleaning up the dozen or so major sites and hundreds of smaller sites that were or are used to produce the US nuclear weapons arsenal and to develop nuclear technologies for national defense and for peaceful purposes. Contaminants and waste materials include the radionuclides associated with nuclear weapons, such as plutonium and tritium, and more common pollutants and wastes of industrial activity such as chromium, chlorinated solvents, and polychlorinated biphenyls (PCBs). Quite frequently hazardous wastes regulated by the Environmental Protection Agency are co-mingled with radioactive wastes regulated by the Nuclear Regulatory Commission to yield a {open_quotes}mixed waste,{close_quotes} which increases the cleanup challenges from several perspectives. To help OTD and its investigators meet DOE`s cleanup goal, technology performance specifications are being implemented for research and development and DT&E projects. Technology performance specifications or {open_quotes}performance goals{close_quotes} describe, quantitatively where possible, the technology development needs being addressed. These specifications are used to establish milestones, evaluate the status of ongoing projects, and determine the success of completed projects.

Purdy, C.; Schutte, W.E. [Dept. of Energy, Germantown, MD (US). Office of Environmental and Waste Management; Erickson, M.D.; Carpenter, S.C.; Doskey, P.V.; Lindahl, P.C.; Pflug, A.D. [Argonne National Lab., IL (US)

1993-07-01

458

Biodegradation of organic compounds in vadose zone and aquifer sediments  

SciTech Connect

The microbial processes that occur in the subsurface under a typical Midwest agricultural soil were studied. A 26-m bore was installed in November of 1988 at a site of the Purdue University Agronomy Research Center. Aseptic collections of soil materials were made at 17 different depths. Physical analysis indicated that the site contained up to 14 different strata. The site materials were primarily glacial tills with a high carbonate content. The N,P, and organic C contents of sediments tended to decrease with depth. Ambient water content was generally less than the water content, which corresponds to a -0.3-bar equivalent. No pesticides were detected in slurry incubations of up to 128 days. The sorption of atrazine and metolachlor was correlated with the clay content of the sediments. Microbial biomass (determined by direct microscopic count, viable count, and phospholipid assay) in the tills was lower than in either the surface materials or the aquifer located at 25 m. The biodegradation of glucose and phenol occurred rapidly and without a lag in samples from the aquifer capillary fringe, saturated zone, and surface soils. In contrast, lag periods and smaller biodegradation rates were found in the till samples. Subsurface sediments are rich in microbial numbers and activity. The most active strata appear to be transmissive layers in the saturated zone. This implies that the availability of water may limit activity in the profile.

Konopka, A.; Turco, R. (Purdue Univ., West Lafayette, Indiana (USA))

1991-08-01

459

Source apportionment of airborne particulate matter using organic compounds as tracers  

NASA Astrophysics Data System (ADS)

A chemical mass balance receptor model based on organic compounds has been developed that relates source contributions to airborne fine particle mass concentrations. Source contributions to the concentrations of specific organic compounds are revealed as well. The model is applied to four air quality monitoring sites in southern California using atmospheric organic compound concentration data and source test data collected specifically for the purpose of testing this model. The contributions of up to nine primary particle source types can be separately identified in ambient samples based on this method, and approximately 85% of the organic fine aerosol is assigned to primary sources on an annual average basis. The model provides information on source contributions to fine mass concentrations, fine organic aerosol concentrations and individual organic compound concentrations. The largest primary source contributors to fine particle mass concentrations in Los Angeles are found to include diesel engine exhaust, paved road dust, gasoline-powered vehicle exhaust, plus emissions from food cooking and wood smoke, with smaller contribution from tire dust, plant fragments, natural gas combustion aerosol, and cigarette smoke. Once these primary aerosol source contributions are added to the secondary sulfates, nitrates and organics present, virtually all of the annual average fine particle mass at Los Angeles area monitoring sites can be assigned to its source.

Schauer, James J.; Rogge, Wolfgang F.; Hildemann, Lynn M.; Mazurek, Monica A.; Cass, Glen R.; Simoneit, Bernd R. T.

460

Partitioning of Organic Contaminants and Tracer Compounds in a CO2-Brine System at High Salinities  

NASA Astrophysics Data System (ADS)

Nonionic chemical species including gases and organic compounds partition between the fluid CO2 phase and the aqueous phase in geologic carbon sequestration systems. The injection and migration of CO2 in geologic carbon sequestration systems covers a wide range of pressure and temperature, so it is important to understand the partitioning of these compounds at various P-T conditions and salinities. Geochemical data is particularly lacking for the partitioning of organic contaminant compounds and tracer compounds between highly saline brines and CO2. Most groundwater is relatively low in organic contaminants; however, groundwater associated with hydrocarbon migration pathways, enhanced oil recovery (EOR), and hydrocarbon storage or extraction can contain high concentrations of known organic contaminants. CO2 injection in these systems may therefore be more likely to result in partitioning of contaminants into the CO2 phase that could, upon migration, represent an important risk to groundwater resources. We present the experimental apparatus and determination of partition coefficients between brine and CO2 for a suite of compounds including benzene, toluene, ethylbenzene, xylene (BTEX), and low molecular weight polynuclear aromatic hydrocarbons (PAHs). In addition, partition coefficients are determined for the important gas phase tracer compounds: SF6 and Krypton covering a P-T envelope consistent with CO2 injection and plume migration to the near surface.

Thomas, B.; Kharaka, Y. K.; Rosenbauer, R. J.; Janesko, D.; Trutna, J.

2011-12-01

461

Organic compounds downstream from a treated-wastewater discharge near Dallas, Texas, March 1987  

USGS Publications Warehouse

Water and streambed-sediment samples were collected on March 9 and 10, 1987 from one site upstream and three sites downstream of the discharge from a municipal wastewater-treatment plant on Rowlett Creek. Purge-and-trap, closed-loop stripping, and ph-adjusted solvent extraction methods for water samples, and a Soxhlet-solvent extraction method for streambed sediment were used with gas chromatography/mass spectrometry for separation and identification of organic compounds. Results of the analyses confirm the persistence of many organic compounds in water as far as 13.5 kilometers down- stream from the wastewater-discharge point. These compounds include: (1) the volatile organic com- pounds chloroform, 1,2-dichlorobenzene, 1,4-dichlorobenzene, tetrachloroethene, and trichlo- roethene; (2) several linear alkylbenzene compounds, octyl phenol, and a tetramethylbutyl phenol isomer that are related to detergent use; (3) 9-phenyl- 9H-carbazole, a compound related to cal tars and coal compustion residues; and (4) caffeine. The only compound detected in water in concentrations greater than U.S. Environmental Protection Agency's maximum contamination levels for drinking water was tetra- chloroethene (6.0 micrograms per liter) in a sample collected 13.5 kilometers downstream from the dis- charge point. Compounds identified in the streambed- sediment samples include a xylene isomer at 7.7 kilometers and chrysene, fluoranthene, pyrene, and a xylene isomer at 13.5 kilometers downstream from the wastewater discharge.

Buszka, P. M.; Barber, L. B., II; Schroeder, M. P.; Becker, L. D.

1994-01-01

462

In silico estimation of DMSO solubility of organic compounds for bioscreening.  

PubMed

Solubility of organic compounds in DMSO is an important issue for commercial and academic organizations handling large compound collections or performing biological screening. In particular, solubility data are critical for the optimization of storage conditions and for the selection of compounds for bioscreening compatible with the assay protocol. Solubility is largely determined by the solvation energy and the crystal disruption energy, and these molecular phenomena should be assessed in structure-solubility correlation studies. The authors summarize our long-term experimental observations and theoretical studies of physicochemical determinants of DMSO solubility of organic substances. They compiled a comprehensive reference database of proprietary data on compound solubility (55,277 compounds with good DMSO solubility and 10,223 compounds with poor DMSO solubility), calculated specific molecular descriptors (topological, electromagnetic, charge, and lipophilicity parameters), and applied an advanced machine-learning approach for training neural networks to address the solubility. Both supervised (feed-forward, back-propagated neural networks) and unsupervised (Kohonen neural networks) learning methods were used. The resulting neural network models were validated by successfully predicting DMSO solubility of compounds in independent test selections. PMID:15006145

Balakin, Konstantin V; Ivanenkov, Yan A; Skorenko, Andrey V; Nikolsky, Yuri V; Savchuk, Nikolay P; Ivashchenko, Andrey A

2004-02-01

463

Characterization and mass load estimates of organic compounds in agricultural irrigation runoff.  

PubMed

Investigations of agricultural chemicals in surface runoff typically target nutrients or specific pesticides; however, numerous other organic compounds are regularly applied to agricultural fields in pesticide formulations, irrigation water, soil amendments and fertilizers. Many of these compounds have toxicological significance. We conducted a broad spectrum analysis of surface runoff from individual irrigated agricultural fields in coastal southern California to characterize organic compounds amenable to analysis by gas chromatography-mass spectrometry and to estimate the mass flux of selected chemicals. Aqueous phase extracts contained several pesticides, as well as personal care product ingredients and pharmaceutically active compounds