classifications of volatile organic compounds

... concentrations of volatile organic compounds (VOCs) is a matter of significant concern with respect to the long term impacts on human health and environment While transport is the greatest contributor of ... multitude of sources for these compounds and the spectrum of health effects that VOCs are required to be monitored in urban atmospheres This report gives a comparative account of concentrations of BTX ... State of Maharashtra, namely, Mumbai, Nagpur and Pune Diurnal and seasonal variability of these compounds has been analyzed average annual temperature of 27°C and average annual rainfall of 2422...

Ngày tải lên: 13/01/2020, 05:26

... the transcript level of defense-related genes [3,13], and end with metabolic changes including release of volatile organic compounds (VOCs) [1,3,13-15] and production of toxic compounds in the plants ... the VEG gland of Spodoptera exigua caterpillars contain elicitors that induce plant defenses by regulating the expression of genes involved in the biosynthesis of volatile organic compounds (VOCs) ... Secretions from the ventral eversible gland of Spodoptera exigua caterpillars activate defenserelated genes and induce emission of volatile organic compounds in tomato, Solanum lycopersicum Simon...

Ngày tải lên: 27/05/2020, 01:24

... concentration of compounds in the headspace of the urine samples by increasing the ionic strength of these samples, which result in a richer profile of VOCs detected by GC-MS [11] Although the addition of ... GC-MS, Volatile organic compounds, Urine, Freeze-dry *Correspondence: ragg005@aucklanduni.ac.nz Department of? ?Cellular and Molecular Physiology, Institute of? ?Translational Medicine, University of? ?Liverpool, ... °C, freeze-dried, with the addition of 1 ml of saturated NaCl solution (salt), with the addition of 1 ml of 5M HCl solution (acid) or with the addition of ml of 5M NaOH solution (base) The results...

Ngày tải lên: 29/05/2020, 13:33

... MINISTRY OF EDUCTION AND TRAINING HA NOI UNIVERSITY OF SCIENCE AND TECHNOLOGY Ngo Quoc Khanh LOW TEMPERATURE CATALYTIC OXIDATION OF VOLATILE ORGANIC COMPOUNDS (VOCs) OVER CATALYSTS OF CuO-Co3O4 ... LIST OF PUBLICATIONS 107 REFERENCES 108 APPENDIX 117 v|Page LIST OF TABLES Table 1.1 Definition of volatile organic compounds (VOCs) Table 1.2 Summary of ... DISSERTATION OF ENVIRONMENTAL ENGINEERING Ha Noi – 2021 MINISTRY OF EDUCTION AND TRAINING HA NOI UNIVERSITY OF SCIENCE AND TECHNOLOGY Ngo Quoc Khanh LOW TEMPERATURE CATALYTIC OXIDATION OF VOLATILE ORGANIC...

Ngày tải lên: 07/12/2021, 19:37

... and fate of contaminants in the subsurface and is often applied to volatile organic compounds (VOC) in groundwater samples [1–4] The principle is based on monitoring the isotopic ratio of one or ... injection of soil extracts containing VOC, limited to a volume of a few μL for splitless injection, the use of purge & trap allows the analysis of 2.5 mL of TGDE soil extract, or 830 μL of methanol ... selected volatile organic compounds detected in ground water - a review of selected literature, Open-File Report 20 06-1338 (20 06) http://pubs.usgs.gov/ofr/20 06/1338/, doi:10.3133/ofr20061338...

Ngày tải lên: 25/12/2022, 02:13

... Department of Commerce (US) Department of Energy (US) Division of Energy Resources (Massachusetts) Electrical Generation unit Energy Information Administration (US Department of Energy) Department of ... contain emission inventories of the three precursors of ozone: VOCs, NOx, and CO.4 This report is part of that SIP submittal Massachusetts is in attainment of all of the other NAAQS so is not ... includes estimates of annual emissions of PM10, PM2.5, SO2, and NH3, all of which contribute to regional haze and PM concentrations 1.3 USES OF EMISSION INVENTORIES Different types of inventories...

Ngày tải lên: 17/10/2022, 23:58

... capability of multiplexing [10] Taking advantage of great potential that fiber optic sensors offer, a novel vapochromic material, whose optical properties change reversely in presence of organic ... (a) Detail of the rise and stabilization of the optical reflected power when the response of the sensor when exposed to different ethanol concentrations (b) Detail of the fall response of the sensor ... The response of the sensor has been evaluated for five different VOCs, and a deeper study has been made for vapors of three different alcohols Keywords: Fiber optic sensor, Volatile Organic Compound,...

Ngày tải lên: 24/11/2022, 17:41

... boiling point of the solvent for a long time § Co-extraction of non -volatile compounds § Losses of volatile compounds if concentration steps are required due to the use of large volumes of organic ... Potential losses of most polar terpenes (oxygenated ones) and chemically most active compounds § Loss of volatile compounds § Low efficiency (in terms of volume of essential oil per g of plant) Foliage ... case, relative amounts of compounds should be more representative of the amounts of the headspace, due to the absence of the selectivity effects of specific coatings However, compounds present in...

Ngày tải lên: 17/03/2023, 16:32

... 1 NOMENCLATURE OF ORGANIC COMPOUNDS ©2010, 2003, 1980, by David A. Katz. All rights reserved. Organic chemistry is the chemistry of carbon compounds. Carbon has the ability ... are skeletal or line structures: There are a range of structures used to represent organic compounds: Before we start naming organic compounds, it is important to understand how carbon ... and physical properties of another class of compounds. A. Halogen Derivatives of Hydrocarbons Functional Group: - X (F, Cl, Br, I) General Formula: R-X Naming of Halides Halogens attached...

Ngày tải lên: 14/02/2014, 08:20

... provided by the Technical Services Division of the Bay Area Air Quality Management District Abstract Trends in the composition and reactivity of volatile organic compound (VOC) emissions from motor ... has occurred since that time due to the phase-out of methyl tert-butyl ether (MTBE) and other ethers in gasoline Introduction Volatile organic compounds are important precursors to ozone and secondary ... global climate (Seinfeld and Pandis, 1997; IPCC, 2001) The main anthropogenic sources of volatile organic compounds are motor vehicle-related, with significant additional emissions arising from...

Ngày tải lên: 05/03/2014, 20:20

... The 12 of 17 MILLET ET AL.: VOLATILE ORGANICS AT THE PITTSBURGH SUPERSITE D07S07 Figure 8 Coefficient of determination... tunnel, Switzerland) part III: Results of organic compounds, ... timed to coincide with the elution of the compounds of interest. Calibration curves for all of the individual compounds were obtained by dynamic dilu- tion of multicomponent low-ppm level standards ... January 2005. [1] Primary and secondary contributions to ambient levels of volatile organic compounds (VOCs) and aerosol organic carbon (OC) are determined using measurements at the Pittsburgh...

Ngày tải lên: 05/03/2014, 21:20

... profiles of individual oxygenated species. (b) Comparison of total oxygenated volatile organic chemical (SOVOC) abundance with that of total nonmethane hydrocarbons (SNMHC). TAN is the sum of ... twice that of nonmethane hydrocarbons (SC 2 -C 8 NMHC). Throughout the troposphere, the OH reactivity of OVOC is comparable to that of methane and far exceeds that of NMHC. A comparison of these ... differences. Mixing ratios of OVOC were strongly correlated with each other as well as with tracers of fossil and biomass/biofuel combustion. Analysis of the relative enhancement of selected OVOC with...

Ngày tải lên: 14/03/2014, 20:20

... for determination of organic compounds in finished drinking water, source water, or drinking water in any treatment stage The method is applicable to a wide range of organic compounds that are ... EXPOSURE RESEARCH LABORATORY OFFICE OF RESEARCH AND DEVELOPMENT U.S ENVIRONMENTAL PROTECTION AGENCY CINCINNATI, OHIO 45268 525.2-1 METHOD 525.2 DETERMINATION OF ORGANIC COMPOUNDS IN DRINKING WATER ... base, and generating a list of tentatively identified compounds with their retention times and scan numbers The software must also allow integration of the ion abundance of any specific ion between...

Ngày tải lên: 22/03/2014, 14:20

... body cavity, primarily the abdominal organs VOC Volatile organic compound(s) volatile Compounds with a boiling range of 0° to 290°C yeasts—Species of fungi that grow as single cells zeophylic—Dry-loving ... ideal conditions, detect as little as 10-20 grams of some elements, and 10-19 grams of most elements It is fully capable of analysis of trace amounts of material from samples as small as micron and, ... residences of asthma patients Identify areas or sources of elevated levels of allergen(s) Determine the effectiveness of allergenic-dust control measures ©2002 CRC Press LLC Most of the information...

Ngày tải lên: 11/08/2014, 07:20

... Two natural sources of benzene are volcanoes and forest fires Benzene is a natural part of crude oil, gasoline, and cigarette smoke Benzene is one of the major components of JP-8 fuel Industry ... moderate levels of trichloroethylene can get enlarged livers, and high levels of exposure can cause liver and kidney damage Studies of people exposed over long periods to high levels of trichloroethylene ... oil, gas, and coal, and from discharges of ethylbenzene from factories Ethylbenzene gets into the soil by spills of gasoline or other fuels and poor disposal of industrial and household wastes People...

Ngày tải lên: 14/02/2014, 03:20

... fraction of non-exempted volatile organic compounds in the non-propellant portion n = number of non-exempted volatile organic compounds in the non-propellant portion WL = weight (gm) of the non-propellant ... DETERMINATION OF VOLATILE ORGANIC COMPOUNDS (VOC) IN CONSUMER PRODUCTS AND REACTIVE ORGANIC COMPOUNDS IN AEROSOL COATING PRODUCTS APPLICABILITY 1.1 This method (Method 310) applies to the determination of ... the total volatile material in a product and the presence of any compounds prohibited by ARB regulations (“prohibited compounds ) Components of the product that not meet the definition of a VOC...

Ngày tải lên: 14/03/2014, 20:20

... and si are the values of wind direction and wind speed of sample i The ranges of wind direction and wind speed are divided into a series of subranges having similar numbers of samples in each Then ... The principle of the PTR-MS is the reaction of organic species in ambient air with H3O+ ions, generated from the hollow cathode discharge of water vapor, to produce the protonated organic species ... overfitting of c13-benzene for the case of 10 sources Neither poor fit nor over fit is acceptable So the number of sources for this analysis was chosen to be During the experiments, FIGURE Profiles of...

Ngày tải lên: 22/03/2014, 14:20

... 2370 E C Apel et al.: Chemical evolution of volatile organic compounds Fig 14 Results of a MM model run to test of the sensitivity of the model to specific compounds The model was initialized with ... evolution of volatile organic compounds Fig The top 20 compounds measured at T0 (top panel) and T1 (lower panel) in terms of mixing ratios between 09:00 and 18:00 local time averaged over the month of ... of volatile organic compounds Fig The top 20 compounds measured from T0 (top panel), T1 (middle panel) and the C130 platform (lower panel), in terms of OH reactivity averaged over the month of...

Ngày tải lên: 28/03/2014, 20:20

... Three-dimensional molecular configuration and composition of some of the compounds discussed in this report The Quality of Our Nation’s Waters Volatile Organic Compounds in the Nation’s Ground Water and Drinking-Water ... environment, other compounds occur only as a result of manmade activities, and some compounds have both origins V olatile organic compounds (VOCs) are ground-water contaminants of concern because of very ... well samples PCE–TCA Chloroform–PCE Chloroform–MTBE PCE–TCE Dibromochloromethane– chloroform Chloroform–TCA TCA–TCE PCE–MTBE Bromoform– dibromochloromethane Bromoform–chloroform Public well samples...

Ngày tải lên: 14/03/2014, 19:20

... Statement of typical rates of consumption of chemicals, a description of the physical and chemical nature of wastes, and rates of waste production; concentrates, residues, etc.; Definition of the ... Testing Plan for Removal of Volatile Organic Chemicals by Air Stripping Technology 2-1 Chapter 3: EPA/NSF ETV Equipment Verification Testing Plan for Removal of Volatile Organic Chemicals by ... by a statistical analysis of the data An example of a satisfactory statement of performance objectives would be: “This system is capable of reducing the concentration of 1,1,2-trichloroethylene...

Ngày tải lên: 14/03/2014, 19:20