volatile organic compounds in the atmosphere

... products, and plastics, as well as in the synthesis of other organic compounds VOCs also are used in the dry cleaning of clothing, in refrigeration units, and in the degreasing of equipment and home septic ... restricts the downward movement of water and contaminants to the underlying confined part of the Edwards aquifer, resulting in a smaller VOC occurrence in the confined area than in the unconfined ... understanding the quality of drinking-water supplies including the monitoring of river intakes and production wells of large CWSs, as well as the continued sampling of domestic wells In addition,...

Ngày tải lên: 14/03/2014, 19:20

... identified as a single point in Fig Point (∼17:00) is an interception of the plume at a lower altitude upon return into the MCMA The higher mixing ratios of MTBE at the beginning and the end of the flights ... evolution of volatile organic compounds (lower panel) shows the averaged mixing ratios for the top 20 VOCs obtained on the C130 during the over-flights and the pie chart to the right of the bar chart ... further reduction of the boundary layer height in the morning together with some contribution from traffic and industry during the early morning before the boundary layer has expanded During the...

Ngày tải lên: 28/03/2014, 20:20

... noise in mfc Although it is difficult to determine the exact starting and ending points of the noise interval, the selected noise range should be sufficiently long to reflect the noise information ... are presented in Figures 10-14 The plot showing emitter locations was produced by superimposing the wind directional plot (blue area) onto the map where the corresponding emitters in the observed ... corresponds to the wind direction plot for this source The red × at the center of the blue area is the sampling site of the reasons why isoprene and M87 occur in the same source The KD value of...

Ngày tải lên: 22/03/2014, 14:20

... 19% The total explained variance of the model was therefore 66.5% In order to test the discriminant power of the exhaled VOC pattern, a multinomial logistic regression was made using the coding ... identifying biomarkers of early lung cancer probably require the use of a panel rather than single substances [17] The main finding of our study was that none of selected VOCs alone distinguished the ... [20]; furthermore, it allowed us to measure most of the substances of interest proposed in the literature Another reason for the difference in VOC identification may be the different clinical characteristics...

Ngày tải lên: 12/08/2014, 18:21

... weight of the reactive organic compounds contained in aerosol coating products, for the purpose of determining compliance with the Aerosol Coatings Regulation 5.1 The testing begins when the Executive ... to determine the boiling point for a compound or for a mixture If the boiling point exceeds 216oC, the compound or mixture is an LVP-VOC If the boiling point is less than 216oC, then the weight ... portion of the product sample is analyzed to determine the reactive organic compounds in the sample, including the presence of any prohibited compounds This analysis is conducted by performing the following...

Ngày tải lên: 14/03/2014, 20:20

... and Lindvall, T., 1993 Volatile organic compounds in ventilating air in buildings at different sampling points in the building and their relationship with the prevalence of occupant symptoms Indoor ... of volatile compounds (VOC) and formaldehyde in the Swedish housing stock In: Indoor Air '93, Proceedings of the 6th Interantional Conference on Indoor Air Quality and Climate, Helsinki, Finland, ... Cometto-Muniz and Cain (1995) An evaluation of the usefulness of these refined indices of VOC exposure is beyond the scope set out for the working group, and is therefore not included in the present...

Ngày tải lên: 28/03/2014, 19:20

... naturally in crude oil and in the tolu tree It is produced in the process of making gasoline and other fuels from crude oil Toluene is also used in making paints, paint thinners, fingernail polish, ... as a cleaning fluid, in industry and dry cleaning businesses, and in the household Carbon tetrachloride also was used in fire extinguishers and as a fumigant to kill insects in grain These uses ... naturally in petroleum and coal tar and is formed during forest fires Xylene is used as a solvent and in the printing, rubber, and leather industries It is used as a cleaning agent and a thinner...

Ngày tải lên: 14/02/2014, 03:20

... are marked increases in the future demand of all organic products This augurs well for the growth of the organic industry in the Eastern Cape and in South Africa in general The findings of this ... the Ciskei include the economic and industrial hub of the province harbouring the major towns, airports and industrial zones The provincial headquarters are also located in the Ciskei According ... respectively The results presented in Figure and can be explained by the fact that the organic industry in South Africa is relatively new and the domestic market is limited in the variety of organic...

Ngày tải lên: 14/02/2014, 03:20

... in 2004, an 11% increase due to the growing popularity of regional markets, the on 2003 increase of green conscience including The formation of The organic food production is stepping up in the ... concern, beginning with the first step of organic product getting The achievement of the organic product under the Obtaining organic products is possible, if the green form a reference model is the result ... recent amendment to the organic The NOP has raised the profile of organic products and legislation has allowed some in the second largest in the they are becoming highly visible in mainstream retailers...

Ngày tải lên: 14/02/2014, 08:20

... confirms the hypothesis that the silk is indeed present in two states, soluble and insoluble, the latter being in some way protected from dissolution in water The peculiarity of the WSM led to the ... characterize these proteins are presently in progress Above all these distinctions, the global amino acid composition showed clearly that the proteins extracted by the two methods are not the same On the ... extract and study organic compounds of the biomineral nacre, by bypassing the demineralization step We think that it may present a new perception of how the different fractions of the organic matrix...

Ngày tải lên: 21/02/2014, 01:21

... aeruginosa This bacterium was able to survive the routine disinfection of the inhalant during manufacturing by forming a biofilm comprised of many colonies The contaminated inhalers contained ... Soil contains organic matter only near the surface The organic compounds arise mostly from the action of microorganisms Most of the organic matter is trapped in colloids and is not in equilibrium ... and the immune system Biofilms were recognized in 1994 following a case that involved the infection of hundreds of asthmatics It was found that all the asthmatics used the same inhalant contaminated...

Ngày tải lên: 14/03/2014, 19:20

... consequences during conductive heating in the subsurface Boiling of water in the vicinity of the heater can markedly dry the formation and decrease the thermal conductivity, steepening the temperature ... well, but also the rate of recovery increases by slowing the transmission of the pressure signal and increasing the pressure differential between the well and the atmosphere Other factors, such ... of them are intended to increase the partitioning of organic chemicals into vapor phases where they can be recovered by SVE processes In addition, one of the heating methods, conductive heating,...

Ngày tải lên: 14/03/2014, 19:20

... interesting when thinking about installing them in a building All of them could be controlled on line and real time in parallel, so if one doesn’t work properly, it wouldn’t affect the rest of the ... is fixing the sensing material onto the fiber In many cases, it is in solid state and has to be solved and then deposited The implementation of the sensor involves several steps: removing the cladding, ... connect the fibers and avoid noise due to a bad alignment Other gases can interfere the measure, but it can be overcome making the input signal more robust using modulations [17] Depending on the final...

Ngày tải lên: 14/03/2014, 20:20

... which contains the papers presented during the Study Week on “Chemical Events in the Atmosphere and their Impact on the Environment” held at the seat of the Academy from the 7th to the 11th of ... present some information about the philosophy, the methodology and the scope o the present meeting, that is, the guidelines f followed by $allthe previous Study Weeks The main object of the Pontifical ... as well as in the laboratory on models, on the causes of acid depositions and on the role of fluorocarbons on the ozone layer and the impact of the COz increase in the atmosphere on the climate...

Ngày tải lên: 16/03/2014, 12:29

... by adding the solvent to the disk, drawing about half through the disk, allowing it to soak the disk for about a minute, then drawing the remaining solvent through the disk Note: Soaking the disk ... homogeneous The resulting concentration of these compounds in the water should be µg/L 11.1.4 Periodically transfer a portion of the sample into the solvent reservoir The water sample will drain into the ... procedures 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...

Ngày tải lên: 22/03/2014, 14:20

... the absorption at the wavelength followed (e.g DA420Æ min)1), in keeping with the literature [9] The complexity of the kinetic trend, i.e a biphasic profile (Fig 3), and the possibility that the ... red, in this case, would remove the H-atom from the OH group of the hindered phenol in an almost thermoneutral step; the resulting 2,4,6tri-t-butylphenoxyl radical drives the reaction towards the ... electrochemical determinations in order to verify whether there was any pH dependence of the Ep of sulfonephthaleins, and, if any, whether it proceeded in the same direction as the pH dependence of the sulfonephthalein...

Ngày tải lên: 23/03/2014, 21:20

... means, in general, an increase of CBZ in the effluent within the whole treatment process Similar findings for CBZ are mentioned in the literature [6] At this point, there is no information about the ... endorsed in the present study Page of 13 (Figure 4) In summary, the polar fraction exhibited, in comparison with the other remaining wastewater fractions, the highest inhibition values in the influent ... assurance The negative controls documented the alterations in the bioluminescence intensity of the tested bacteria in the absence of any toxicant during incubation The inhibition of the positive...

Ngày tải lên: 20/06/2014, 20:20

... of the genes involved in sulfate assimilation and the synthesis of the sulfur-containing amino acids (Figure 2c) This appears to conflict with our phenotypic observations at the sampling point ... formation during fermentation is well studied, the factors leading to residual H S in the final wine remain to be elucidated Previous studies have pointed out a link between the kinetics of H2S ... evaluated whether the source for the initial increase in H2S production, which was observed following rehydration with nutrients, was the amino acid component of the mixture (detailed in Table 2)...

Ngày tải lên: 20/06/2014, 23:20

... means, in general, an increase of CBZ in the effluent within the whole treatment process Similar findings for CBZ are mentioned in the literature [6] At this point, there is no information about the ... endorsed in the present study Page of 13 (Figure 4) In summary, the polar fraction exhibited, in comparison with the other remaining wastewater fractions, the highest inhibition values in the influent ... assurance The negative controls documented the alterations in the bioluminescence intensity of the tested bacteria in the absence of any toxicant during incubation The inhibition of the positive...

Ngày tải lên: 21/06/2014, 17:20

... Important Compounds, and Uses 1116 Inorganic Tin Compounds 1116 Organotin Compounds 1116 Distribution in the Environment, Foods, and Living Organisms 1117 Contamination of the Environment 1117 Inorganic ... Inorganic Tin 1117 Organic Tin 1118 Contamination of Food and Living organisms 1119 Uptake, Absorption and Elimination in Plants, Animals and Humans 1120 Tin and Inorganic Tin Salts 1120 Organotin Compounds ... slightly changed title influencing the length of the whole text, the organization of the introductory and the analytical part as well Subsequently the final working phase started in 2002 This updated...

Ngày tải lên: 03/07/2014, 16:08