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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Revised suspension and transport methods for the rapid assessment of exposure to particulate emissions from surface contamination sites

Stewart, Duncan Francis, 1947- 03 August 2011 (has links)
Not available / text
2

Revised suspension and transport methods for the rapid assessment of exposure to particulate emissions from surface contamination sites

Stewart, Duncan Francis, Liljestrand, Howard M. January 2004 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisor: Howard Liljestrand. Vita. Includes bibliographical references. Also available from UMI.
3

Research to determine source efficiences (E[subscript s]) for scrabbled and rough concrete surfaces

Bak, Michael T. 18 March 2003 (has links)
The Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM) requires that Final Status Surveys be performed on materials and surfaces that vary in surface smoothness and/or uniformity. To obtain accurate survey data, it may be necessary to adjust detector response for these surface variations. NUREG-1507 refers to such surface efficiency adjustment factors as ��[subscript s], the source efficiency. This parameter is meant to be a detector-independent, yet surface and nuclide-dependent parameter that can be used to adjust observed count rate to provide a true measure of the degree of contamination present. Key measurements in the calculation of (��[subscript s]) are the energy of the radionuclide contaminant and the average height of the detector above the contaminated surface. During the last year, Oregon State University, Department of Nuclear Engineering and Radiation Health Physics provided technical support for a Final Status Survey of a commercial nuclear plant. OSU NE/RHP has conducted research and experimentation to determine site-specific source efficiency (��[subscript s]) values for concrete surfaces which had undergone simulated decommissioning activities, such as surface scabbling. Source efficiency (��[subscript s]) values were determined for seven separate scabbled concrete surfaces which had been prepared using 5 tool types. Fourteen concrete cores were intentionally contaminated with known amounts of two beta emitting radionuclides: ��������Tl and ������Tc. The ��[subscript s] values were examined as a function of the type of scabbled surface as well as the contaminating nuclide. / Graduation date: 2003
4

Resistance of adsorbed nisin to exchange with bovine serum albumin, ��-lactalbumin, ��-lactoglobulin, and ��-casein at silanized silica surfaces

Muralidhara, Lakamraju 20 December 1994 (has links)
Nisin is an antibacterial peptide, which when adsorbed on a surface can inhibit bacterial adhesion and viability. The ability of noncovalently immobilized nisin to withstand exchange by the milk proteins bovine serum albumin, ��-lactoglobulin, ��-lactalbumin, and ��-casein on surfaces that had been silanized with dichlorodiethylsilane to exhibit high and low hydrophobicities was examined using in situ ellipsometry. Kinetic behavior was recorded for nisin adsorption for 1h and 8h, followed in each case by rinsing in protein-free buffer solution, and sequential contact with a single milk protein for 4h. Concerning nisin adsorption to each surface, a higher adsorbed mass was consistently recorded on the hydrophilic relative to the hydrophobic surface, independent of adsorption time. While desorption was greater from the hydrophilic surface in the 1h test, the amount desorbed was quite similar on each surface in the 8h tests. The sequential data were consistent with the assumptions that nisin organization at the interface involved adsorption in at least two different states, possibly existing in more than one layer, and that in the absence of exchange, upon addition of the second protein adsorbed mass would increase by an amount equivalent to its experimentally observed monolayer coverage. The Mass of nisin exchanged was generally higher on the hydrophobic compared to the hydrophilic surface presumably because of the presence of a more diffuse outer layer in the former case. ��-casein was the most effective eluting agent among the proteins studied, while ��-lactalbumin was the least effective, apparently adsorbing onto the nisin layers with little exchange. Both bovine serum albumin and ��-lactoglobulin were moderately effective in exchanging with adsorbed nisin, with the amount of nisin removed by bovine serum albumin being more substantial, possibly due to its greater flexibility. / Graduation date: 1995
5

Laser induced desorption time of flight mass spectrometer analysis of adsorbed surface contaminants on vacuum ultraviolet lithography optic materials

Surpaneni, Yamini. Allen, Susan D. January 2003 (has links)
Thesis (M.S.)--Florida State University, 2003. / Advisor: Dr. Susan Davis Allen, Florida State University, College of Engineering, Dept. of Electrical and Computer Engineering. Title and description from dissertation home page (viewed Apr. 12, 2004). Includes bibliographical references.
6

Applications of grazing-angle reflection absorption Fourier transform infrared spectroscopy to the analysis of surface contamination : a thesis submitted in the partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry at the University of Canterbury, Christchurch, New Zealand /

Hamilton, Michelle January 1900 (has links)
Thesis (Ph. D.)--University of Canterbury, 2007. / Typescript (photocopy). "January 2007." Includes bibliographical references. Also available via the World Wide Web.
7

Effectiveness of a closed system device in reducing occupational exposure and environmental concentrations of anticancer drugs

Vyas, Nitin January 2014 (has links)
Owing to their non-selective nature, anti-cancer drugs affect both cancerous and non-cancerous cells and present a major health risk to healthcare staff working with them. This project was conducted at Derriford Hospital, Plymouth, to investigate the extent of contamination with anti-cancer drugs on work surfaces and the environmental emissions of these drugs. In the Isolator study, surface contamination arising from the preparation of five anticancer drug infusions (epirubicin, fluorouracil, cisplatin, oxaliplatin and carboplatin) in a pharmaceutical isolator and external surfaces of infusion bags and syringes using a conventional syringe and needle technique was investigated and compared with that obtained using a closed system drug transfer device (Tevadaptor). Wipe samples were taken for a period of one week from pre-defined areas in a pharmaceutical isolator and from the surface of prepared Intra-Venous (IV) infusion bags and pre-filled syringes to obtain baseline data. Gloves and preparation mats used during this period were also collected. Following a one-week operator familiarisation period, the Tevadaptor device was then introduced for cytotoxic preparation and wipe-sampling of surfaces and collection of consumables was continued for a further week (intervention period). The samples obtained were then analysed by HPLC and ICP-MS. The baseline contamination data from Tevadaptor isolator study was undetected to 0.9 ng cm-2 (epirubicin), undetected to 3.58 ng cm-2 (5-FU) and 0.05-0.92 ng cm-2 (Pt) in the wipe samples from the pharmaceutical isolator surfaces; amounts on glove samples were 1100-6100 ng/glove (epirubicin), 300-8100 ng/glove (5-FU) and 1-6 ng/glove (platinum). During the intervention phase isolator surface contamination was not detected in all samples for 5-FU and epirubicin and platinum was detected on the isolator surfaces in the range of 0.002-0.09 ng cm-2. The use of Tevadaptor resulted in a reduction of contamination on external surfaces by a factor of 10 or more for all marker drugs. A ward study investigated the surface contamination in the oncology out-patient department caused by cisplatin, oxaliplatin, carboplatin and gemcitabine. The study compared the effect of using the Tevadaptor to prepare and administer anticancer drugs infusions on ward surface contamination to the current UK standard practice. A questionnaire was also distributed to participating staff members to assess the user-friendliness of Tevadaptor. Wipe samples were taken from pre-defined areas from the oncology out-patients department and gloves used by nursing staff for assembly and administration of the above drugs were also collected. Sample collection followed a similar schedule to the Tevadaptor isolator study. The baseline ward surface contamination ranged from undetected to 4.97 ng cm-2 (gemcitabine) and 3.1 ng cm-2 (platinum). In the case of gloves used by nursing staff the levels of contamination ranged from undetected to 1251 ng/glove (gemcitabine) and 405.4 ng/glove (platinum). The contamination on ward surfaces during the intervention phase ranged from undetected to 3.21 ng cm-2 (gemcitabine) and 2.69 ng cm-2 (platinum) and contamination levels on gloves ranged from undetected to 9252 ng/glove (gemcitabine) and 1319 ng/glove (platinum). During the intervention phase there was a reduction in frequency of contamination, even though the total amount of surface contamination by anticancer drugs did not always decrease in comparison to baseline data, presumably due to unaccounted spillages. A drain study investigated the presence of platinum in hospital wastewater as a measure of contamination caused by the excretion of platinum-based anticancer drugs by patients. Platinum was measured over a three week period in one of the main drains and in the effluent of the oncology ward. The study showed the presence of measurable quantity of platinum which ranged from 0.02 to 140 μg L-1 in the oncology effluent and 0.03 to 100 μg L-1 in the main drain. Data from this study was coupled with published measurements on the removal of the drugs by conventional sewage treatment and then concentration of platinum arising from each drug was predicted in recipient surface waters as a function of water flow rate. Although predicted concentrations were below EMEA guidelines warranting further risk assessment, the presence of potentially carcinogenic, mutagenic and teratogenic substances in surface waters is cause for concern. The results showed that a closed system drug transfer device (CSTD) used in conjunction with an isolator is highly efficient in reducing surface contamination with anti-cancer drugs. However, despite current best practice contamination on ward surfaces remained even after the use of a CSTD. Nursing as well as healthcare staff should be educated of these results and the risks of occupational exposure to low levels of anti-cancer drugs and the use of PPE should be emphasised. Results of the drain study form the basis of preliminary estimates of the likely concentrations of platinum-based drugs in surface waters and their potential environmental impacts.
8

Applications of grazing-angle reflection absorption Fourier transform infrared spectroscopy to the analysis of surface contamination

Hamilton, Michelle LoAnn January 2007 (has links)
Cleaning validation of pharmaceutical manufacturing equipment is required by legislation. Generally, wet chemical techniques are employed using swabbing and/or rinse sampling methods. These are generally either selective and time consuming, or less selective and give results in a shorter period. The infrared reflection absorption spectroscopy (IRRAS) technique explored here attempts to deliver accurate, selective surface contamination information in real time to complement current methods and reduce down-time. The IRRAS instrument used in this research is a Fourier transform infrared (FTIR) spectrometer coupled by an IR fibre-optic cable to a grazing-angle sampling head with a fixed incidence angle of 80°. The introduced flexibility permits collection of in situ spectra from contaminated surfaces. Calibration models are developed using the multivariate, linear partial least squares (PLS) statistical method. The research focuses on sodium dodecyl sulfate (SDS), a model cleaning agent, on metal (aluminium and stainless steel) and dielectric (glass, EPDM and silicone) surfaces. The effects of surface finish are investigated for SDS on stainless steel. Calibrations for SDS and paracetamol in the presence of each other on glass surfaces are examined, as well as a common industrial cleaner (P3 cosa® PUR80) on polished stainless steel. For the calibration sets in this thesis, RMSECV values were < 0.41 µg cm⁻², corresponding to conservative surface residues detection limits of better than ~0.86 µg cm⁻². However, RMSECV values depend on the calibration loading range, and the detection limits were typically ~0.2 µg cm⁻² for loading ranges 0-2.5 µg cm⁻². These are below visual detection limits, generally taken to be 1-4 µg cm⁻², depending on the analyte and substrate. This shows that IRRAS is a viable method for the real-time detection and quantification of surface contamination by surfactants and active pharmaceutical ingredients on metals and dielectrics.
9

Large scale entrance surface dose survey and organ dose measurements during diagnostic radiology using the Harshaw 5500 and 6600 TLD systems

Broadhead, Dawn January 2001 (has links)
No description available.
10

Applications of grazing-angle reflection absorption Fourier transform infrared spectroscopy to the analysis of surface contamination

Hamilton, Michelle LoAnn January 2007 (has links)
Cleaning validation of pharmaceutical manufacturing equipment is required by legislation. Generally, wet chemical techniques are employed using swabbing and/or rinse sampling methods. These are generally either selective and time consuming, or less selective and give results in a shorter period. The infrared reflection absorption spectroscopy (IRRAS) technique explored here attempts to deliver accurate, selective surface contamination information in real time to complement current methods and reduce down-time. The IRRAS instrument used in this research is a Fourier transform infrared (FTIR) spectrometer coupled by an IR fibre-optic cable to a grazing-angle sampling head with a fixed incidence angle of 80°. The introduced flexibility permits collection of in situ spectra from contaminated surfaces. Calibration models are developed using the multivariate, linear partial least squares (PLS) statistical method. The research focuses on sodium dodecyl sulfate (SDS), a model cleaning agent, on metal (aluminium and stainless steel) and dielectric (glass, EPDM and silicone) surfaces. The effects of surface finish are investigated for SDS on stainless steel. Calibrations for SDS and paracetamol in the presence of each other on glass surfaces are examined, as well as a common industrial cleaner (P3 cosa® PUR80) on polished stainless steel. For the calibration sets in this thesis, RMSECV values were < 0.41 µg cm⁻², corresponding to conservative surface residues detection limits of better than ~0.86 µg cm⁻². However, RMSECV values depend on the calibration loading range, and the detection limits were typically ~0.2 µg cm⁻² for loading ranges 0-2.5 µg cm⁻². These are below visual detection limits, generally taken to be 1-4 µg cm⁻², depending on the analyte and substrate. This shows that IRRAS is a viable method for the real-time detection and quantification of surface contamination by surfactants and active pharmaceutical ingredients on metals and dielectrics.

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