Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 321-336). Available also in a digital version from Dissertation Abstracts.

Thesis (Ph.D.) - University of Queensland, 2005. / Includes bibliography.

Thesis (M.S.)--Ball State University, 2009. / Title from PDF t.p. (viewed on June 07, 2010). Includes bibliographical references (p. [53]-56).

Thesis (Ph.D.) - University of Queensland, 2004. / Includes bibliography.

Thesis (Ph. D. in Chemical Engineering)--Vanderbilt University, Aug. 2005. / Title from title screen. Includes bibliographical references.

No description available.

Indiana University-Purdue University Indianapolis (IUPUI) / Researchers have shown links between various hydrocarbons and carbonyl compounds and diseases, such as cancer using exhaled breath analysis through gas chromatography/mass spectroscopy (GC/MS) analysis of volatile organic compounds (VOCs). Trained canines can detect these VOCs and can differentiate a patient suffering from cancer from a healthy control patient. In this project, an attempt has been made to develop highly sensitive sensors for the detection of low concentrations of aldehyde VOCs, such as nonanal, using conductive polymer composites (CPCs) and functionalized gold nanoparticles (f-GNPs). Facile methods have been used to enhance the sensitivity and cross-selectivity of the fabricated sensors towards nonanal. Interdigitated electrodes (IDEs) are fabricated through a photolithography process. Sensors of PEI/carbon black (CB) composite were developed via spin-coating of the material followed by the heat treatment process. Sensors of 1-Mercapto-(triethylene glycol) methyl ether functionalized GNPs are developed via drop-casting of nanomaterial and f-GNP/PEI sensors are fabricated by spin casting PEI film on top of f-GNPs. Fourier Transform Infrared (FTIR) analysis, X-Ray Diffraction (XRD) analysis, contact angle measurement, and Field Emission Scanning Electron Microscopy (FESEM) analysis was conducted to characterize the fabricated devices. The fabricated sensors have been tested with a low concentration of nonanal, nonanone, dodecane, and 1-octanol in dry air. Multiple sensors are fabricated to ensure sensors reproducibility. The sensors have been exposed repeatedly to the targeting VOC toxiv assess the repeatability of the sensors. PEI/CB sensor degradation was studied over a period of 36 days. The fabricated PEI/CB film could detect (1-80 ppm) of nonanal with higher selectivity, than the f-GNPs. The sensor0s sensitivity to nonanal was over fourteen times higher than 2-nonanone, 1-octanol, and dodecane. This shows the high selectivity of the fabricated sensor toward nonanal. In addition, the proposed sensor maintained its sensitivity to nonanal over time showing minimal degradation. The sensor response to nonanal at a relative humidity (RH) of 50% and 85% dropped less than 13% and 32% respectively. The Response of f-GNP sensors to nonanal (400 ppb - 15 ppm), dodecane (5 - 15 ppm), 1-octanol (5 - 15 ppm), and 2-nonanone (5 - 15 ppm) presented a sensitivity (∆R=R0) of 0.217%, 0.08%, 0.192% and 0.182% per ppm of the VOCs respectively. Despite the high sensitivity to the targeting VOCs, the fabricated sensors were damaged in an environment with relative humidity (RH) at 45%. A thin layer of PEI over the film was developed to ensure the sensor could tolerate longtime exposure to water vapor in an environment with RH up to 85% and enhance the sensor selectivity towards nonanal. The f-GNP/PEI sensors with nonanal (400 ppb- 15 ppm), dodecane (100 -200 ppm), 1-octanol (5 - 15 ppm) and 2-nonanone (5 - 15 ppm) presented sensitivity (∆R=R0) of 0.21%, 0.017%, 0.0438% and 0.0035% per ppm of the VOCs respectively. / 2021-04-24

M. Tech. (Chemistry, Department of Chemistry, Faculty of Applied and Computer Science), Vaal University of Technology / The dissertation deals with volatile organic compounds that evaporate from the water-oil separate in the refinery, which causes bad odour around the neighbouring communities, the existence of these compounds are being identified and quantified in different seasons for the year. VOC are emitted whenever wastewater is exposed to the atmosphere. As such, emission points include open drains ditches, manhole sewer outfalls and surface fore bays, separators and treatment ponds. Refinery units such as reactors, fractionators are periodically shutdown and emptied for internal inspection and maintenance. The amount of VOC entering the wastewater is not monitored. The effluent water discharged from the refinery is not checked for the amount ofVOC present. The monitoring of the amount of VOC in wastewater stream may lead to a decrease in the emission. From the quantified results at different season, the summer session has the highest VOC emission due to the heat that causes more vapours. The preparation of a method for determination of VOC's in air presents many difficulties, because of their high volatilities and low concentrations in air. As well, the results of determination are affected by the properties of the sorbent used, mainly its sorption capacity, depending on the properties of the compound under determination. The methods for sampling and analytical procedures for the measurements of volatile organic compounds that are hazardous to air pollution are compendium method T0-14 and sorbent tube method compendium T0-17. Both methods (sorbent tube and canister) differ from each other in their extraction and detection techniques. The well suitable method for the VOC determination is canister method; this method gives more representative sample of the ambient monitoring of 24 hours, where as sorbent tube can do for 2 hours only. The canister method is more advantages due to the sample that will be still remaining for further analyses or re-check. The integrity of API water-oil separator has been improved to cause less evaporation during high temperature season. As the temperature drops from season to season, the VOC also comes down as its being seen in this study that on the winter results that all the VOC were below 90 1-lg/kg. / National Petroleum Refiners of South Africa laboratory

Thesis (Ph. D.)--University of Canterbury, 2009. / Typescript (photocopy). "16 September 2009." Includes bibliographical references (p. [217]-222). Also available via the World Wide Web.

Source: Masters Abstracts International, Volume: 47-06, page: 3475. Adviser: Thomas H. Stock. Includes bibliographical references.