Dissertations / Theses on the topic 'Dose to water'
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1
Rosser, Karen Elizabeth. "Measurement of absorbed dose to water for medium energy x-rays." Thesis, University College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338897.
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Das, Chandan (Chandan K. )., and Justin Holland. "Hand powered portable ultraviolet sterilizing water bottle with active UV dose sensing." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/59490.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, September 2007 [first author]; and, (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, June 2006 [second author].Includes bibliographical references (p. 71).
A portable hand powered water sterilization device was created to address a portion of the growing epidemic of global water contamination. As being more supply chain independent and having an active dose sensing component that monitors the water to insure sterilization, our device boasts far more than any current off-the-shelf devices. The device is completely hand powered via a hand crank generator. A spermicidal ultraviolet light bulb, rated at 253.7nm (UV-C), was integrated with a common NalgeneTM water bottle. Along with the bulb, UV. dose sensing electronics and a hand crank generator were incorporated as well, with the generator supplying power to both the bulb and the photodiode circuitry. Results show that eradication of common waterborne bacteria, protozoa, and viruses occurs after cranking the generator for approximately 41 seconds in clear water and up to 65 seconds in turbid water. The total weight added to the water bottle was less than a pound.
by Chandan Das and Justin Holland.
S.B.
3
Isam, Salih M. Musa. "Radon in natural waters : analytical methods, correlation to environmental parameters, radiation dose estimation, and GIS applications /." Linköping, 2003. http://www.bibl.liu.se/liupubl/disp/disp2003/med820s.pdf.
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Maniquis, Virginia. "Monte Carlo Dose Verification of an X-Ray Beam in a Virtual Water Phantom." Thesis, Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/10559.
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Monte Carlo (MC) methods are widely accepted as the most accurate technique for calculating dose distributions in radiation therapy physics. Simulating the particle transport through the treatment head of a linear accelerator utilizing a MC based code is both a widespread and practical approach to determining detailed clinical beam characteristics such as the energy, angular and spatial distribution of particles which are needed to properly quantify dose. One particular and versatile MC code, the Monte Carlo N-Particle (MCNP) radiation transport code, developed by Los Alamos National Laboratory, has been commonly used to model ionizing radiations for medical physics applications.
In this thesis, a Varian 2100C linear accelerator (linac) is modeled and the electron and photon transport through the primary components of the treatment head are simulated using MCNP Version 5_1.3. The 6 MV photon spectra was characterized in a standard 10 x 10 cm2 field and subsequent dose calculations were made in a Virtual Water (VW) phantom. Energy fluence, percent depth dose and beam profile measurements were taken in a modeled VW phantom and the calculated data was compared to measured reference data. In addition, a human phantom was modeled for future dose calculations using the modeled linac.
The linac model created can incorporate different beam energies for determining the dose distribution of multiple beam treatments in phantoms for standard 6 MV plans. The adaptability of this MCNP model allows for any number of geometries and sources encountered in medical physics to be computed and applied with relative ease. Future studies can involve adding complex multi-leaf collimator beam shaping and calculating the dose in human phantom models, which would serve as a basis for studies involving MCNP modeling for dose optimization in medical physics applications.
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Hodges, Jennifer Susan. "Radionuclide contaminated sediments in the Lune and Wyre estuaries and their dose implications." Thesis, Lancaster University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337344.
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Lobdell, John Llewellyn. "Dose rate and spectral photon measurements around a loarge BWR using a tissue equivalent plastic scintillator." Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/15861.
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Ma, Jie. "Alternative Water Soluble Polymeric Films to Poly(vinyl alcohol) for Single Unit Dose Products." Doctoral thesis, Universitat Rovira i Virgili, 2020. http://hdl.handle.net/10803/669413.
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La beina de detergent de safareig és una bossa soluble en aigua que conté detergent de roba altament concentrat, actualment la bossa és de poli (alcohol vinílic) (PVA). A mesura que el negoci continua creixent, P&G voldria trobar altres materials capaços de substituir el film PVA. L’objectiu d’aquest projecte de doctorat és buscar materials alternatius per al film SUD, que tinguessin una compatibilitat detergent similar, solubilitat en aigua, permeabilitat i propietats mecàniques com la pel·lícula PVA. A més, voldríem descobrir si el nou material aportaria nous beneficis.
En aquesta tesi, es van preparar films fetes de polietil·len glicol (PEG), alginat de sodi, material Lactips, material de caseinat, així com les seves barreges amb PVA, es van provar propietats d’aquestes films i es van preparar prototips d’algunes de les films. Es va seleccionar la colada de solucions com a mètode per preparar les films.
Aquesta tesi està composta per 8 capítols. A part del capítol 1 (introducció general i objectius), el capítol 2 (materials i mètodes de prova) i el capítol 8 (conclusions generals i treballs futurs),
El capítol 3 descriu les films basades en PEG i les seves propietats;
El capítol 4 descriu les films basades en alginat de sodi i les seves propietats;
El capítol 5 descriu les films basades en materials de Lactips, així com les seves propietats;
El capítol 6 descriu el prototipat de bossa amb la film Lactips i tracta l'estabilitat de la bossa;
El capítol 7 descriu les films basades en caseinat de sodi i les seves propietats.La cápsula de detergente para ropa es una bolsa soluble en agua que contiene detergente para ropa altamente concentrado, actualmente la bolsa está hecha de poli (alcohol vinílico) (PVA). A medida que el negocio continúa creciendo, P&G desea encontrar algunos otros materiales capaces de reemplazar la film de PVA. El objetivo de este proyecto de doctorado es buscar materiales alternativos para la película SUD, que tendrían una compatibilidad detergente similar, solubilidad en agua, permeabilidad y propiedades mecánicas como la film PVA. Además, nos gustaría descubrir si el nuevo material traería nuevos beneficios. En esta tesis, se prepararon películas hechas de polietilenglicol (PEG), alginato de sodio, material Lactips, material de caseinato, así como sus mezclas con PVA, se probaron las propiedades de esas films y se prepararon prototipos de bolsa de algunas de las films. Se seleccionó la solución de fundición como método para preparar las films. Esta tesis se compone de 8 capítulos. Además del Capítulo 1 (Introducción general y objetivos), el Capítulo 2 (Materiales y métodos de prueba) y el Capítulo 8 (Conclusiones generales y trabajo futuro), El Capítulo 3 describe las films basadas en PEG y sus propiedades; El Capítulo 4 describe las films a base de alginato de sodio y sus propiedades; El Capítulo 5 describe las films basadas en materiales de Lactips, así como sus propiedades; El Capítulo 6 describe la creación de prototipos de bolsa con film Lactips y discute la estabilidad de la bolsa; El Capítulo 7 describe las films a base de caseinato de sodio y sus propiedades.
Laundry detergent pod is a water-soluble pouch that contains highly concentrated laundry detergent, currently the pouch is made of Poly(vinyl alcohol) (PVA). As business continues to grow P&G would like to find some other materials able to replace PVA film. The objective of this PhD project is to look for alternative materials for SUD film, which would have similar detergent compatibility, water solubility, permeability and mechanical properties as PVA film. Additionally, we would like to discover whether the new material would bring new benefits. In this thesis, films made of polyetheylen glycol (PEG), sodium alginate, Lactips material, caseinate material, as well as their blends with PVA were prepared, properties of those films were tested, and pouching prototypes of some of the films were prepared. Solution casting was selected as the method for preparing the films. This thesis is composed of 8 chapters. Apart from Chapter 1 (General introduction and objectives), Chapter 2 (Materials and test methods), and Chapter 8 (General conclusions and future work), Chapter 3 describes PEG-based films and their properties; Chapter 4 describes sodium alginate-based films and their properties; Chapter 5 describes Lactips material-based films, as well as their properties; Chapter 6 describes pouch prototyping with Lactips film and discusses pouch stability; Chapter 7 describes sodium caseinate-based films and their properties.
8
Kelm, Robert S. "In-water neutron and gamma dose determination for a new Cf-252 brachytherapy source." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28121.
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Salih, Isam M. Musa. "Radon in natural waters : Analytical Methods; Correlation to Environmental Parameters; Radiation Dose Estimation; and GIS Applications." Doctoral thesis, Linköpings universitet, Medicinsk radiofysik, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-5221.
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Investigations of radon in natural water and its relation to physical and chemical parameters are outlined in this thesis. In particular, a method for measuring 222Rn in water at low concentrations (~20 mBq.l-1) is described, followed by discussions concerning the design and its application to study both radon and parameters influencing radon levels in natural waters. A topic considered is the impact of fluoride and other aquatic parameters on radon in water. Moreover, variables such as uranium series radionuclides and stable elements in water, bedrock and sediment radioactivity and geology are investigated in two case studies. This was performed by employing radiometric-, chemical-, statistical- and GIS & geostatistical- analyses. The general water chemistry and presence of some elements such as fluoride was observed to influence radon levels in water. Health aspects of radon in drinking water are discussed based on radiation dose assessments. The radiation doses are compared with and added to doses incurred from ingestion of uranium, radium and polonium isotopes in drinking water and inhalation of radon in air in order to estimate total exposures for different age categories. The results may have a potential for future epidemiological studies.
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Phetxumphou, Katherine. "Novel Approaches to Exposure Assessment and Dose Response to Contaminants in Drinking Water and Food." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/94582.
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In the fields of water safety, food safety, and public communications, the overarching goal is to improve public health. Thus, this dissertation focuses on risk assessment and applying novel methods for exposure assessments and dose responses to contaminants in drinking water and foods. Factors that greatly impact contaminant exposures and human dose response include: population susceptibility (i.e., healthy adults or children), different routes of exposures (i.e., ingestion or inhalation), carrier matrices (i.e., water or food), and intricacies of chemical and biological mixtures. Chemical spills, such as the 2014 crude MCHM spill in Charleston, WV, revealed the complexities of both minor and major components in the chemical mixture. Slight shifts in geometric structures (isomers) can affect the fate and transport properties of the chemical mixture and as a result, the level of human exposure and dose response to each component in the chemical mixture. Odorous properties of both minor and major components can affect human inhalation exposure, especially during showering, and can be as detrimental as the ingestion route exposure and are different for healthy adults versus for children. Food contaminants, such as Shiga toxin producing Escherichia coli (STEC) in beef products, can be mitigated through a quantitative microbial risk assessment (QMRA) framework that follows a farm-to-fork model. Methods to ensure greatest microbial reduction include: employed intervention strategies at slaughter plants (i.e., water washing of beef carcass), improved cooking times and temperature methods at the consumer and retail level, and assessed minimum effective dose response modeling for different population susceptibilities. Current public communication tools, including the Drinking Water Taste-and-Odor Wheel or Consumer Confidence Reports (better known as water quality reports), should be redeveloped to uphold water safety. Furthermore, public health campaigns that uses social media strategies and informative websites can better educate the public on food contaminants. Ultimately, the objective is to prevent human illnesses due to water contaminants and foodborne pathogens and to bridge the communication gap between the consumers and the experts concerned with water and food safety.Ph. D.
11
Taylor, Anne Marie, and n/a. "Biomarkers of Cadmium, Lead and Selenium Toxicity in the Marine Bivalve Molluscs Tellina deltoidalis and Anadara trapezia: Linking Exposure, Dose and Response." University of Canberra. Environmental Science, 2009. http://erl.canberra.edu.au./public/adt-AUC20091214.104734.
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The relationships between metal exposure, dose and response were investigated in two
sediment dwelling marine bivalves: a deposit feeder Tellina deltoidalis and a filter feeder
Anadara trapezia. The bivalves were exposed in the laboratory to individual metal spiked
sediments: Cadmium 10 and 50 Ag/g; lead 100 and 300 Ag/g; selenium 5 and 20 Ag/g dry
mass, T. deltoidalis for 28 days A. trapezia for 56 days. A. trapezia was also exposed in the
laboratory for 56 days to sediments from three sites along a metal contamination gradient of
cadmium, lead, selenium, zinc and copper from Lake Macquarie, NSW. Metal total tissue
dose was measured in whole tissue of T. deltoidalis over 28 days and in gill, hepatopancreas
and haemolymph tissues in A. trapezia over 56 days. Subcellular metal distribution,
biologically active metal (BAM) versus biologically detoxified metal (BDM) was measured
in whole tissues of T. deltoidalis at day 28 and in gill and hepatopancreas tissues of
A. trapezia at day 56. Biomarkers of response measured in spiked sediment exposed, at day
28 T. deltoidalis and day 56 A. trapezia were: total antioxidant capacity (TAOC); glutathione
peroxidase enzyme activity (GPx); total glutathione concentration (GSH+2GSSG); reduced to
oxidised glutathione ratio (GSH:GSSG); lipid peroxidation (TBARS); lysosomal membrane
stability and micronuclei frequency. Response indices measured in A. trapezia exposed to
Lake Macquarie sediments were: TAOC, TBARS, lysosomal membrane stability,
micronucleus frequency and condition index. Native A. trapezia and sediments were also
collected from Lake Macquarie and measured for sediment and tissue metal concentrations,
TAOC, TBARS, lysosomal membrane stability and condition index to allow comparison
between chronically exposed and previously unexposed organisms.
T. deltoidalis and A. trapezia accumulated metal over time in all sediment metal exposures
with most reaching equilibrium tissue metal concentrations by the end of the exposure period.
T. deltoidalis generally reached equilibrium with the exposure concentration for cadmium and
lead but had significantly higher selenium tissue concentrations than the sediment metal at the
5 Ag/g exposure. A. trapezia tissue lead was below the sediment concentration for all
exposures including in the native organisms. A high proportion of accumulated lead and
copper in A. trapezia was in the haemolymph, probably associated with haemoglobin which
has a high affinity for these metals`. A. trapezia cadmium tissue concentrations were higher
than the sediment metal in the 10 Ag/g spiked sediment exposure and between half and one
eighth the sediment concentrations in other treatments, including in native organisms.
A. trapezia including the native organisms exposed to selenium sediment concentrations at or
below 5 Ag/g in the Lake Macquarie mixed metal sediments accumulated significantly higher
than ambient selenium tissue concentrations while those exposed to 5 and 20 Ag/g selenium
spiked sediments had lower than ambient selenium tissue concentrations. The majority of
accumulated cadmium, selenium and zinc was associated with the gill/mantle tissues.
A. trapezia hepatopancreas contributed significant selenium concentrations in the later part of
the exposure period indicating and increased contribution from dietary derived selenium.
Native A. trapezia had significantly lower tissue concentrations of selenium, copper and zinc,
higher cadmium and approximately equal lead compared to organisms exposed to similar
sediment metal concentrations in the laboratory.
T. deltoidalis detoxified around 50 % of accumulated cadmium and 70 % of lead while
A. trapezia detoxified around 70 % of accumulated cadmium and 60 % of lead. Much of
T. deltoidalis BDM cadmium was converted to metal rich granules (MRG), while A. trapezia
had most in the metallothionein like proteins (MTLP) fraction. The conversion of lead to
MRG was 75 % of the total BDM in T. deltoidalis while A. trapezia had an even distribution
between MRG and MTLP. The majority of recovered selenium in both species was
associated with the nuclei+cellular debris fraction, probably as protein bound selenium
associated with plasma and selenium bound directly to cell walls. Selenium exposed
organisms had increased BDM selenium burdens which were associated with both MRG and
MTLP fractions, indicating selenium detoxification. The majority of BAM cadmium, lead
and selenium was associated with the mitochondrial fraction in both species with increases in
cadmium burden in this organelle of T. deltoidalis up to 7200 fold; lead 154 fold; and
selenium 7 fold and in A. trapezia up to 84 fold cadmium, 50 fold lead and selenium 7 fold in
exposed organisms compared to controls. The subcellular distribution of all three metals in
T. deltoidalis and A. trapezia indicates active metal detoxification processes which at these
exposure concentrations were unable to prevent significant metal burdens from accumulating
in sensitive organelles.
A contamination gradient of zinc, lead, copper, cadmium and selenium was established in
Lake Macquarie sediments which emanated from the same source. A. trapezia accumulated
all metals in each sediment exposure. Accumulation and tissue distribution patterns of
cadmium, lead and selenium were similar to those of the single metal spiked sediment
exposures. Cadmium and lead BAM burdens increased at all exposures while selenium, zinc
and copper did not.
T. deltoidalis and A. trapezia in the spiked sediment metal exposures generally had reduced
GPx activity. This resulted in an increase in total glutathione concentrations which the
reduced GSH:GSSG ratios indicated was due to a build up of oxidised glutathione.
T. deltoidalis and A. trapezia had reduced TAOC in all laboratory sediment metal exposures
which corresponded with increased TBARS concentrations, lysosomal destabilisation and
micronucleus frequency. A. trapezia exposed to Lake Macquarie metal contaminated
sediments also had a reduction in physiological condition, indicated by the reduced condition
index, after 56 days at the higher metal exposures.
Clear exposure - dose - response relationships have been demonstrated for T. deltoidalis and
A. trapezia exposed to single cadmium, lead and selenium spiked sediments and for
A. trapezia exposed to Lake Macquarie mixed metal contaminated sediments. Detoxification
of all metals was evident in both T. deltoidalis and A. trapezia but detoxification capacity was
exceeded for cadmium, lead and selenium leading to significant accumulation of these metals
in sensitive organelles. The significant relationships, in the laboratory exposed T. deltoidalis
and A. trapezia, between TAOC reduction with increased TBARS, lysosomal destabilisation
and micronuclei frequency and between increased TBARS with lysosomal destabilisation and
micronuclei frequency indicates that increased tissue metal dose and BAM burdens caused
significant impairment of the antioxidant reduction capacity which resulted in a cascade of
effects from lipid peroxidation to cellular perturbation and genotoxic damage. The reduction
in physiological condition in the organisms with the highest tissue metal doses suggests the
response goes beyond subcellular perturbations to whole organism and potentially population
effects.
Chronically metal exposed native Lake Macquarie A. trapezia did not show a clear metal
exposure - dose - response relationship. Accumulation of the essential elements zinc, copper
and selenium appeared to be regulated while cadmium and lead were not. TAOC was
significantly reduced and TBARS significantly increased compared to reference organisms
but lysosomal stability and condition were not significantly affected.
The suite of interrelated biomarkers used offers a weight of evidence approach for
demonstrating adverse effects of metal tissue accumulation in T. deltoidalis and A. trapezia
12
Holm, Kim Marina [Verfasser], and Joao [Akademischer Betreuer] Seco. "Absorbed dose to water measurements in the SOBP of a clinical carbon-ion beam using water calorimetry / Kim Marina Holm ; Betreuer: Joao Seco." Heidelberg : Universitätsbibliothek Heidelberg, 2021. http://d-nb.info/1236403126/34.
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Piyaratna, Nelson, of Western Sydney Nepean University, and Faculty of Science and Technology. "Radiotherapy X-ray dose distribution beneath retracted patient compensators." THESIS_FST_XXX_Piyaratna_N.xml, 1995. http://handle.uws.edu.au:8081/1959.7/363.
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Computer designed missing tissue and dose compensators have been produced and dosimetrically tested under a linear accelerator 6MV X-ray beam. Missing tissues compensators were developed to correct for patient external contour change only. Target dose compensators were developed to achieve a uniform dose throughout the target volume. With compensators present in the beam, data acquisition was repeated in a water phantom and an Anthropomorphic phantom. Clinically acceptable dose uniformity was achieved within these phantoms. For external contour compensation flat isodose curves were obtained giving an even dose in the region of interest. The dose difference found was within plus/minus 3% only. For the phantoms containing inhomogeneities dose uniformity to target volume was achieved within plus/minus 7%. Prediction of radiation dose was made using a GE Target Series 2 Treatment Planning Computer for each of the phantoms. Validation of the computer predicted dose was carried out using diode and TLD measurements. The measured data in the water tank was consistent with the computer data within plus/minus 2% for external contour changes and for inhomogeneities. The TLD measured results in the anthropomorphic phantom agreed with the planning computer results within 6%. Up to 4% of the difference is explainable due to supra-linearity and scatter effectsMaster of Science (Hons) (Physics)
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CHANDRASEKARAN, LATHA. "PREDICTING DISEASE INCIDENCE DUE TO CONTAMINATED INTRUSION IN A WATER DISTRIBUTION SYSTEM." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1155506232.
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McKinney, Julie. "Minimum Ultraviolet Light Dose Determination and Characterization of Stress Responses that Affect Dose for Listeria monocytogenes Suspended in Distilled Water, Fresh Brine, and Spent Brine." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/26756.
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Foodborne illnesses caused by Listeria monocytogenes have long been associated with ready-to-eat (RTE) meats contaminated after the primary thermal process has been applied. It is believed that brine solutions used to chill cooked RTE products may serve as a reservoir for L. monocytogenes becoming a potential point of post-processing contamination for RTE meats. Re-circulating ultraviolet light (UV) systems are being used to inactivate L. monocytogenes in chill brines; however very little has been reported on the dose response of healthy and stressed L. monocytogenes to UV in brine solutions. The objectives of this research were to determine 1) minimum dose of UV required to inactivate L. monocytogenes in distilled water, fresh brine, undiluted spent brine, and diluted spent brine, 2) if adaptation to food processing stresses affects the dose response, and 3) if the acquisition of antibiotic resistance mechanisms provides resistance to ultraviolet light 4) effect of stress adaptation on survival in brine solutions. After UV exposure, populations were reduced as follows from greatest to least: water > fresh brine > 5% spent brine > 35% spent brine > 55% spent brine > 100% spent brine (P â ¤ 0.05). There were no population differences between acid stressed and antibiotic resistant or healthy and heat shocked (P > 0.05). However, acid-stressed and sulfanilamide-resistant were more resistant to UV light than healthy and heat shocked L. monocytogenes (P â ¤ 0.05). Survival in brine solutions (no UV) followed the trend, from greatest to least (P â ¤ 0.05): sulfanilamide-resistant > acid-stressed > healthy > heat-shocked. Population estimates decreased from initial inoculation to final sampling for each cell type suspended in spent brine (P â ¤ 0.05), but only healthy and heat- shocked cells suspended in fresh brine were significantly reduced (P â ¤ 0.05). Knowledge of UV dosing required to control L. monocytogenes in brines used during RTE meat processing, and a greater understanding of the interactions that may influence dose will aid manufacturers in establishing appropriate food safety interventions for these products.Ph. D.
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Zheng, Yifeng. "Studies on biological activities of low dose of phenethylamine from hot water extract of Chlorella pyrenoidosa." Doctoral thesis, Kyoto University, 2020. http://hdl.handle.net/2433/259745.
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京都大学0048
新制・課程博士
博士(農学)
甲第22849号
農博第2432号
新制||農||1082(附属図書館)
学位論文||R2||N5309(農学部図書室)
京都大学大学院農学研究科応用生物科学専攻
(主査)教授 佐藤 健司, 教授 澤山 茂樹, 教授 菅原 達也
学位規則第4条第1項該当
Doctor of Agricultural Science
Kyoto University
DGAM
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Gandhi, Varun N. "Visualization and quantification of hydrodynamics and dose in UV reactors by 3D laser induced fluorescence." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45895.
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The validation of UV reactors is currently accomplished by biodosimetry, in which the reactor is treated as a "black-box" and hence cannot account for the dependence of the dose delivery on the complex hydrodynamics and the spatial variation in UV intensity. Alternative methods, such as fluorescent microspheres as non-biological surrogates and computational fluid dynamics (CFD) simulations, have been developed; however, each method has its shortcomings.
In this study, a novel technique for the spatial and temporal assessment of the hydrodynamics and the UV dose delivered and the link between these two factors in a lab-scale UV reactor using three dimensional laser induced fluorescence (3DLIF) is developed. This tool can also be utilized for the optimization of UV reactors and to provide data for validation of CFD-based simulation techniques. Regions of optimization include areas around the UV lamp where short-circuiting occurred, a longer inlet approach section that enhances the performance of the reactor by reducing short circuiting paths and a longer outlet region to provide greater mixing.
3DLIF allows real time characterization of mixing and dose delivery in a single lamp UV reactor placed perpendicular to flow by capturing fluorescence images emitted from a laser dye, Rhodamine 6G, using a high speed CCD camera. In addition to three-dimensional mixing, the technique successfully visualized the two-dimensional, transient mixing behaviors such as the recirculation zone and the von Karman vortices and the fluence delivery within the reactor, which has not been possible with traditional tracer test techniques. Finally, a decomposition technique was applied to the flow and fluence delivery based concentration data to reveal similar structures that affect these phenomena. Based on this analysis, changing the flow in the reactor, i.e. the Reynolds number, will directly affect the fluence delivery.
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TOYODA, EDUARDO Y. "Evolução das doses no ambiente do Reator IEA-R1 e tendências com base nos resultados atuais." reponame:Repositório Institucional do IPEN, 2016. http://repositorio.ipen.br:8080/xmlui/handle/123456789/26615.
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O Ipen/Cnen-SP possui um Reator de Pesquisa(IEA-R1) em operação desde 1957. Ele utiliza água leve como blindagem, moderador e como fluido refrigerante, o volume desta piscina é de 273m3. Até 1995 a operação do Reator era descontinua, ou seja, operava diariamente sendo desligado no final do dia, a uma potência de 2,0 MW. A partir daquele ano, após algumas modificações de segurança, o Reator passou a operar de forma continua, ou seja, de segunda-feira a quarta-feira sem ser desligado, totalizando 64 horas semanais. A potência também foi aumentando até 4,5 MW em 2012. Em virtude dessas alterações, a saber, operação contínua e do aumento da potência, as doses dos trabalhadores aumentaram e por isso foram realizados vários estudos para diminui-las. Estudos demonstraram que uma das principais limitações para operação de um reator em potência elevada, provém das radiações gama emitidas pelo sódio-24. Outros elementos como magnésio-27, Alumínio-28, Argônio-51, contribuem de forma considerável para a atividade da água da piscina. A introdução de uma camada de água quente em sua superfície, estável e isenta de elementos radioativos com 1,5m a 2m de espessura constituiria uma blindagem às radiações provenientes dos elementos radioativos dissolvidos na água. Estudos de otimização provaram que a instalação da camada quente não era necessária para o regime e potência atual de operação do Reator, pois outros procedimentos adotados eram mais eficazes. A partir desta decisão o serviço de Proteção Radiológica do Reator IEA-R1, montou um programa de avaliação das doses para certificar-se de que elas se mantinham em valores razoáveis baseados em princípios estabelecidos em normas nacionais e internacionais. O intuito deste trabalho é realizar uma análise das doses individuais dos IOE (Individuo Ocupacionalmente Expostos), considerando as mudanças no regime de operação do Reator e sugerir opções de proteção e segurança, viáveis em primeira instância, para reduzir as doses analisadas, visando se chegar aos níveis de referencia de 3 mSv/ano adotados pela instalação em apreço.
Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
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Ververs, James. "A quantitative method for reproducible ionization chamber alignment to a water surface for external beam radiation therapy depth dose measurements." VCU Scholars Compass, 2011. http://scholarscompass.vcu.edu/etd/2600.
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Ionization chambers (ICs) are the most commonly used detectors for radiation therapy dose measurements. Typical IC measurements use cylindrical ICs in a water phantom and therefore require initial IC alignment to the water surface. This alignment has long been ignored and only recently has a qualitative governing recommendation been made. This thesis describes a reproducible methodology for quantitative ionization chamber water surface alignment. Depth-ionization measurements are taken with twenty-eight IC designs under varying conditions including, but not limited to, changes in scan direction, speed, and resolution, radiation beam type, field size, energy, and electron contamination. Measurements are acquired using standard radiotherapy accelerators in the Virginia Commonwealth University Department of Radiation Oncology and at the National Research Council of Canada, where a customized scanning system capable of better than 0.15 mm IC positioning precision is used. Measurements are also performed with standard commercial scanning equipment on the Accuray CyberKnife, a specialized radiosurgery-class accelerator. An analytical model is developed from basic principles to test the theoretical foundations of IC response near a water surface. The theoretical foundation is further validated via Monte Carlo simulation models that fully account for all details of the ICs used to take measurements. It is determined that the dose gradient as a function of depth is maximized when a given IC reaches the water surface when moving from depth in water. This effect is unchanged under all of the measurement scenarios tested. Measurements taken at 0.1 mm resolution for several seconds per point over several millimeters near the surface will yield a gradient peak that can be used for quantitative alignment. Using developed software, multiple scans at variant resolutions can be stitched into typical clinical scans so as not to significantly affect clinical measurement workflow. The recommended measurement method is developed in a format suitable for inclusion into a clinical protocol for depth-ionization measurement acquisition.
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Moji, Kabelo McDonald. "Comparison of measured photon and electron beam dose distributions between 3D water phanton and profiler 2 scanning system, South Africa." Thesis, University of Limpopo (Medunsa Campus), 2013. http://hdl.handle.net/10386/1086.
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Thesis ( MSc ( Physics) ) -- University of Limpopo, 2013.Background and Objectives: To establish whether the profiler 2 scanning system can be used as a substitute for the 3D-water phantom, by comparing the percentage depth doses and beam profiles for both the photons and electron beams, and validating the results using CMS XiO treatment planning system. Methods: Beam data (profiles, percentage depth doses and absolute dosimetry) were acquired for the two systems: (3D-water phantom and profiler 2 scanning system) for beam energies 6 MV and 15 MV photon beams, and 4, 6, 8, 10, 12 and 15 MeV electron beams generated by the Elekta Synergy linear accelerator (linac) for the field sizes of 6 × 6 cm2, 10 × 10 cm2, 14 × 14 cm2, 20 × 20 cm2, and 25 × 25 cm2 at depths of 0.5 cm, 1.0 cm, 2.0 cm, and 5.0 cm respectively. These measurements were acquired using ionization chambers in water and diode detectors in Perspex. The acquired data was sent to CMS XiO treatment planning system for validation. Results: In general, the dose distributions for both systems compared very well with uncertainties within recommended limits. The largest maximum difference in symmetry was 1.6 % for a 6 MV photon beam defined at 25 × 25 cm2 field size. The largest maximum difference in flatness was 2.77 % for a 4 MeV electron beam defined at 10 × 10 cm2 applicator size. The penumbra largest maximum difference was 1.708 cm for 8 MeV electron beam defined at 25 × 25 cm2 applicator size, which was outside the recommended limit of 1.2 cm. The largest maximum difference in field size was 2.388 cm for a 6 MeV electron beam defined at 20 × 20 cm2 applicator size, which was outside the recommended limit of 0.4 cm. The largest maximum difference in percentage depth dose at 10 cm depth was 1.69 % for the 6 MV photon beam. The absolute dose output measurements showed a very good agreement between the two systems to a maximum percentage difference and highest standard deviation of -0.99 % and 0.69 % respectively for the 6 MV photon beam. Validation measurements showed an agreement to less than 1 % and 2 mm for percentage depth doses and beam profiles respectively. Conclusion and recommendation: From the results obtained, it is evident that the profiler 2 scanning system can be used as a substitute for the 3D-water phantom beam data acquisitions during linear accelerator commissioning. The future work based on this study could be to study the limitations involved with the profiler 2 scanning system when used during measurements for commissioning of a linear accelerator. Limitations like field size (maximum field size of 20 × 30 cm2 at SSD = 100 cm), number of Perspex slabs to be used on top of the profiler 2 scanning system and diagonal profile measurements.
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Osinga-Blättermann, Julia-Maria [Verfasser], and Wolfgang [Akademischer Betreuer] Schlegel. "Determination of absorbed dose to water in a clinical carbon ion beam by means of fluorescent nuclear track detectors, ionization chambers, and water calorimetry / Julia-Maria Osinga-Blättermann ; Betreuer: Wolfgang Schlegel." Heidelberg : Universitätsbibliothek Heidelberg, 2017. http://d-nb.info/1180738578/34.
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Silva, Maria Hercília da. "Modelo de procedimentos para elaboração de metodologia de valoração econômica de impactos ambientais em bacia hidrográfica - estudo de caso - Guarapiranga - aplicação da função dose-resposta." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/3/3147/tde-28032008-180244/.
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Este trabalho apresenta a análise dos resultados obtidos, através de pesquisa bibliográfica, sobre o uso dos recursos hídricos na Bacia Hidrográfica do Guarapiranga na Região Metropolitana de São Paulo, cujo uso prioritário é o Abastecimento Público. Identifica os impactos decorrentes tanto pela ocupação desordenada, quanto pela sobreposição de outros usos incompatíveis com a manutenção de sua qualidade e quantidade, existentes em diagnósticos realizados, no intuito de avaliar as distorções na valoração econômica dos danos ambientais. Para valoração desses impactos foi adotada a metodologia da produtividade marginal, onde o papel do recurso ambiental no processo produtivo é representado por uma função dose-resposta, que relaciona o nível de provisão do recurso ambiental (água bruta) ao de produção respectiva do produto no mercado (água tratada). A aplicação desta função permite a mensuração do impacto no sistema produtivo, dada uma variação marginal na provisão do bem ou serviço ambiental, e a partir desta variação, pode - se estimar o valor econômico de uso do recurso ambiental.This paper presents the analysis of the results obtained by means of bibliographic research on the use of water resources in the Guarapiranga River Basin in the metropolitan region of São Paulo, whose use is the priority Utilities. It identifies the impacts caused by the occupation both disorderly, as the overlapping of the other uses incompatible with the maintenance of their quality and quantity, existing in diagnoses made, in order to assess the distortions in the economic valuation of environmental damage. For valuation of these impacts was adopted the methodology of marginal productivity, where the role of the environmental resource in the production process is represented by a dose-response function, which relates the level of provision of the environmental resource (water gross) to the production of their product on the market (treated water). The application of this function allows the measurement of impact on the production system, given a marginal variation in the provision of environmental goods or services, and from this change, one can estimate the economic value of resource usage environment.
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Stewart, Kristin Joy. "The development of new devices for accurate radiation dose measurement: a guarded liquid ionization chamber and an electron sealed water calorimeter." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=18423.
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In this work we developed two new devices that aim to improve the accuracy of relative and reference dosimetry for radiation therapy: a guarded liquid ionization chamber (GLIC) and an electron sealed water (ESW) calorimeter. With the GLIC we aimed to develop a perturbation-free energy-independent detector with high spatial resolution for relative dosimetry. We achieved sufficient stability for short-term measurements using the GLIC-03, which has a sensitive volume of approximately 2 mm3. We evaluated ion recombination in pulsed photon beams using a theoretical model and also determined a new empirical method to correct for relative differences in general recombination which could be used in cases where the theoretical model was not applicable. The energy dependence of the GLIC-03 was 1.1% between 6 and 18 MV photon beams. Measurements in the build-up region of an 18 MV beam indicated that this detector produces minimal perturbation to the radiation field and confirmed the validity of the empirical recombination correction. The ESW calorimeter was designed to directly measure absorbed dose to water in clinical electron beams. We obtained reproducible measurements for 6 to 20 MeV beams. We determined corrections for perturbations to the radiation field caused by the glass calorimeter vessel and for conductive heat transfer due to the dose gradient and non-water materials. The overall uncertainty on the ESW calorimeter dose was 0.5% for the 9 to 20 MeV beams and 1.0% for 6 MeV, showing for the first time that the development of a water-calorimeter-based standard for electron beams over a wide range of energies is feasible. Comparison between measurements with the ESW calorimeter and the NRC photon beam standard calorimeter in a 6 MeV beam revealed a discrepancy of 0.7±0.2% which is still under investigation. Absorbed-dose beam quality conversion factors in electron beams were measured using the ESW calorimeter for the Exradin A12 and PTW Roos ionizationDans ce travail nous avons développé deux nouveaux détecteurs qui visent à améliorer l'exactitude de la dosimétrie relative et de référence en radiothérapie: une chambre d'ionisation liquide gardée (GLIC) et un calorimètre d'eau scellé pour les électrons (ESW). Avec la GLIC nous avons visé à développer un détecteur indépendant de l'énergie et libre de perturbations avec une résolution spatiale élevée pour la dosimétrie relative. Nous avons atteint une stabilité suffisante pour des mesures à court terme en utilisant la GLIC-03, qui a un volume sensible d'approximativement 2 mm3. Nous avons évalué la recombinaison générale des ions dans des faisceaux de photons pulsés en utilisant un modèle théorique et nous avons également déterminé une nouvelle méthode empirique, permettrant de corriger pour les différences relatives de recombinaison générale, qui pourrait être employée dans les cas où le modèle théorique ne serait pas applicable. La dépendance d'énergie du GLIC-03 était 1.1% dans des faisceaux de photon entre 6 et 18 MV. Les mesures dans la région de déséquilibre électronique ('build-up') d'un faisceau du 18 MV ont indiqué que ce détecteur introduit une perturbation minimale du champ de rayonnement et ont confirmé la validité de la correction empirique de recombinaison. Le calorimètre ESW a été conçu pour mesurer directement la dose absorbée dans les faisceaux d'électrons cliniques. Nous avons obtenu des mesures reproductibles pour des faisceaux de 6 à 20 MeV. Nous avons déterminé les corrections nécessaires pour tenir compte des perturbations du champ de rayonnement introduites par le récipient de verre du calorimètre et du transfert thermique de conduction dû au gradient de dose et au fait que les matériaux ne sont pas de l'eau. L'incertitude globale sur la dose pour le calorimètre ESW était 0.5% pour les faisceaux de 9 à 20 MeV et 1.0% pour 6 MeV, prouvant pour la première fois que le d
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ANDRADE, LIMA RICARDO de. "Avaliacao da dose na populacao da regiao urano-fosfatica do Nordeste que utiliza os recursos hidricos da regiao." reponame:Repositório Institucional do IPEN, 1996. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10470.
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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Hartmangruber, David Patrick. "Using MAVRIC sequence to determine dose rate to accessible areas of the IRIS nuclear power plant." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37123.
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The objective of this thesis is to determine and analyze the dose rate to personnel throughout the proposed IRIS nuclear power plant. To accomplish this objective, complex models of the IRIS plant have been devised, advanced transport theory methods employed, and computationally intense simulations performed.
IRIS is an advanced integral, light water reactor with a 335 MWe expected power output (1000 MWth). Due to its integral design, the IRIS pressure vessel has a large downcomer region. The large downcomer and the neutron reflector provide a great deal of additional shielding. This increase in shielding ensures that the IRIS design easily accomplishes the regulatory dose limits for radiation workers. However, The IRIS project set enhanced objectives of further reducing the dose rate to significantly lower levels, comparable or below the limit allowed for general public.
The IRIS nuclear power plant design is very compact and has a rather complex geometric structure. Programs that use conventional methods would take too much time or would be unable to provide an answer for such a challenging deep penetration problem. Therefore, the modeling of the power plant was done using a hybrid methodology for automated variance reduction implemented into the MAVRIC sequence of the SCALE6 program package. The methodology is based on the CADIS and FW-CADIS methods. The CADIS method was developed by J.C. Wagner and A. Haghighat. The FW-CADIS method was developed by J.C. Wagner and D. Peplow. Using these methodologies in the MAVRIC code sequence, this thesis shows the dose rate throughout most of the inhabitable regions of the IRIS nuclear power plant. This thesis will also show the regions that are below the dose rate reduction objective set by the IRIS shielding team.
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Nilsson, Kenneth A. "Simulating Accidental Exposures to deliberate Intrusions in Pipe Networks." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1091122400.
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Patel, Raj B., and Raj B. Patel. "Prediction of Human Intestinal Absorption." Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/624487.
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The proposed human intestinal absorption prediction model is applied to over 900 pharmaceuticals and has about 82.5% true prediction power. This study will provide a screening tool that can differentiate well absorbed and poorly absorbed drugs in the early stage of drug discovery and development. This model is based on fundamental physicochemical properties and can be applied to virtual compounds. The maximum well-absorbed dose (i.e., the maximum dose that will be more than 50 percent absorbed) calculated using this model can be utilized as a guideline for drug design, synthesis, and pre-clinical studies.
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Barreta, Priscila Aparecida Teixeira de Muno. "Influência da administração concomitante de fluoreto através da água de beber no metabolismo e incorporação de chumbo em ratos: estudo dose-resposta." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/25/25149/tde-16072014-134512/.
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O objetivo deste estudo foi avaliar os níveis de F e Pb circulantes, excretados e incorporados no tecido ósseo em ratos expostos simultaneamente ao F e Pb através da água de beber desde a gestação, levando-se em consideração diferentes doses de Pb e F e dois tipos de sais fluoretados. Para tal, 280 ratos Wistar machos foram divididos em 28 grupos contendo 10 animais cada. As diferenças entre os grupos foram as concentrações, na água de beber, de Pb (0, 1, 10 ou 30 mg/L) e de F (0, 5, 50 ou 100 mg/L), em dois tipos de sais (NaF ou H2SiF6). Os animais foram expostos ao tratamento desde a gestação até completarem 80 dias de vida, quando foram eutanasiados e o sangue foi removido para análise de Pb e F (no sangue total e plasma, respectivamente). Também foi coletado o fêmur direito, para análises de F e Pb. Ainda foram coletadas amostras de urina e fezes (24 horas) dos animais alojados em gaiolas metabólicas (n=6 por grupo) a cada 14 dias, desde o desmame até a eutanásia, para análises de F e Pb. As análises de Pb foram feitas por ICP-MS e as análises de F foram feitas com o eletrodo, após difusão facilitada por hemametildisiloxano (plasma, fêmur e fezes) ou pelo método direto (urina). Os dados foram analisados por ANOVA a 3 critérios, seguida pela teste de Tukey (p<0,05). Observou-se que o composto fluoretado, a concentração de F na água e a concentração de Pb na água interferiram na retenção de F e de Pb no organismo, indicando que a administração concomitante de F e Pb através da água de beber é capaz de aumentar a incorporação de F e de Pb no tecido ósseo e que a excreção urinária e fecal destes elementos não é suficiente para explicar a maior retenção dos mesmos no organismo. Quando o F foi adicionado à água na forma de H2SiF6, concentrações significativamente mais altas de F foram observadas no plasma e osso, e quantidades significativamente menores de F foram excretadas através da urina, aumentando a biodisponibilidade do F no organismo. Maior biodisponibilidade do Pb também foi observada quando o H2SiF6 foi utilizado em comparação ao NaF, com concentrações significativamente maiores de Pb no osso, a despeito de uma maior excreção urinária e fecal de Pb. Estes resultados confirmam achados de estudos epidemiológicos e de prova-de-conceito prévios de que a exposição concomitante a sílicofluoretos e Pb é capaz de aumentar a biodisponibilidade do Pb, assim como também do F no organismo. Estudos adicionais devem ser conduzidos para investigar os mecanismos que levam a estes efeitosThe aim of this study was to evaluate the circulating levels of F and Pb, as well as the levels of F and Pb excreted and uptaken by bone, in rats co-exposed to F and Pb from the drinking water, taking into account different doses of Pb and F and two types of fluoridated salts. For this purpose, 280 male Wistar rats were divided into 28 groups (n=10). The differences among the groups were the concentrations of Pb (0, 1 , 10 or 30 mg/L ) and F [0, 5, 50 or 100 mg/L in two types of salts (NaF or H2SiF6)] added in the drinking water to which the females and their offspring were exposed, 1 week before mating until the pups completed 80 days of life. At 80 days of age, the animals were euthanized. Blood was collected for Pb and F analysis (whole blood and plasma, respectively). The right femur was also collected for Pb and F analyses. In addition, throughout the experimental period, urine and feces were collected from the animals housed in metabolic cages (n=6/group) every 14 days, for F and Pb analyses. Pb was analyzed by ICP-MS and F was measured with the electrode, after hexamethyldisiloxane-facilitated diffuson (plasma, femur and feces) or by the direct method (urine). Data were analyzed by 3-way ANOVA and Tukey´s test (p<0.05). It was observed that the F compound, the F concentration and the Pb concentration in the drinking water interfered in the retention of Pb and F in the organism. These data indicate that co-exposure to F and Pb from the drinking water increases the F and Pb uptake by bone. This cannot be completely explained by the urinary and fecal excretion of F and Pb. When F was added to the water as H2SiF6, significantly higher F concentrations were observed in plasma and bone, while significantly lower amounts of F were excreted through urine, increasing the bioavailability of F in the organism. Also higher bioavailability of Pb was observed upon administration of H2SiF6 when compared to NaF (significantly higher concentrations of Pb were observed in bone, despite the excretion of Pb from feces and urine was higher). These results reinforce the findings of previous epidemiological and proof-of-concept studies that report increased bioavailability of Pb and F in the organism upon coexposure to silicofluorides and Pb. Additional studies should be conducted to investigate the mechanisms that lead to these effects.
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Kubalík, David. "Možnosti zlepšení agregace a separace suspenze při úpravě pitné vody." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2013. http://www.nusl.cz/ntk/nusl-216952.
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This work is focused on improvement of particle formation and separation processes in drinking water. These include the comparison of the dynamics of different coagulation reagents (aluminum sulphate and ferric sulphate) to find the optimal dose of coagulant. During centrifugation test is important to find such a setting centrifuge where we get the best results. In this work we studied the influence of the total mineralization at the optimum dose of coagulant.
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Perichon, Nicolas. "Etablissement des références nationales, en termes de dose absorbée, par calorimétrie dans l’eau, pour les faisceaux de rayons X de moyenne énergie, applicables en radiothérapie." Thesis, Paris 11, 2012. http://www.theses.fr/2012PA112153/document.
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Les références actuelles, pour les rayons X de moyenne énergie en radiothérapie, sont établies au LNHB en termes de kerma dans l’air. La dose absorbée dans l’eau, grandeur d’intérêt pour la radiothérapie, est déduite de ces valeurs par transfert conformément aux protocoles internationaux. Ce travail de thèse a permit d’établir les références en termes de dose absorbée dans l’eau dans les conditions de référence des protocoles en utilisant la méthode de calorimétrie dans l’eau. La calorimétrie est la mesure de la dose absorbée à partir de l’élévation de température. Un « calorimètre-eau » a été conçu et réalisé afin d’effectuer des mesures à 2 cm de profondeur : conditions de référence définies par le protocole AIEA TRS-398. Les débits de dose absorbée dans l’eau ainsi déterminés ont été comparés aux valeurs issues de l’application des protocoles fondés sur le kerma dans l’air. Un écart maximum inférieur à 2.1 % a été trouvé par rapport à la calorimétrie. L’incertitude type associée aux valeurs calorimétriques étant inférieure à 0.8 % et celle associée aux valeurs issues des protocoles étant de l’ordre de 3.0 %, les résultats sont compatibles aux incertitudes des méthodes près. Grâce à ces nouvelles références, la détermination de la dose absorbée dans l’eau dans ce type de faisceau pourra désormais être réalisée en appliquant le protocole AIEA TRS-398, conduisant ainsi à une forte réduction des incertitudes (facteur 3 par rapport au protocole AIEA TRS-277). Actuellement, aucun autre laboratoire primaire ne possède un tel instrument permettant l’établissement direct de ces références dans les conditions recommandées par les protocolesLNE-LNHB current references for medium energy X-rays are established in terms of air kerma. Absorbed dose to water, which is the quantity of interest for radiotherapy, is obtained by transfer dosimetric techniques following a methodology described in international protocols. The aim of the thesis is to establish standards in terms of absorbed dose to water in the reference protocol conditions by water calorimetry. The basic principle of water calorimetry is to measure the absorbed dose from the rise in temperature of water under irradiation. A calorimeter was developed to perform measurements at a 2 cm depth in water according to IAEA TRS-398 protocol for medium energy x-rays. Absorbed dose rates to water measured by calorimetry were compared to the values established using protocols based on references in terms of air kerma. A difference lower than 2.1% was reported. Standard uncertainty of water calorimetry being 0.8%, the one associated to the values from protocols being around 3.0%, results are consistent considering the uncertainties. Thanks to these new standards, it will be possible to use IAEA TRS-398 protocol to determine absorbed dose to water: a significant reduction of uncertainties is obtained (divided by 3 by comparison with the application of the IAEA TRS-277 protocol). Currently, none of the counterparts’ laboratories own such an instrument allowing direct determination of standards in the reference conditions recommended by the international radiotherapy protocols
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Kassouf, Helene. "Formation of Trihalomethanes (THMs) as Disinfection by-Products (DBPs) when Treated Municipal Wastewater is Disinfected with Sodium Hypochlorite." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6522.
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Disinfection is an essential process in the treatment of municipal wastewater before the treated wastewater can be discharged to the environment. Hillsborough County's Northwest Regional Water Reclamation Facility (NWRWRF) in Tampa, Florida, currently uses ultraviolet (UV) light for disinfection. However, this method has proven expensive to implement and maintain, and may not be effective if the light transmission is poor. For these reasons, Hillsborough County is considering switching from UV light to sodium hypochlorite for disinfection. However, hypochlorite (chlorine) disinfection has disadvantages as well, such as the production of disinfection by-products (DBPs) such as trihalomethanes (THM) and haloacetic acids (HAAs), which may have adverse impacts on the quality of surface waters that receive the treated wastewater.
Therefore, the objectives of this research are (1) to compare NWRWRF typical operating conditions and water quality to those of two nearby facilities (River Oaks and Dale Mabry Advanced Wastewater Treatment Plants) that currently employ chlorine disinfection, (2) to determine the chlorine demand of treated effluent from NWRWRF, (3) to quantify the DBP formation potential of treated effluent from NWRWRF, and (4) to determine the effects of temperature, reaction time, and chlorine dose on chlorine demand and THM formation.
To inform laboratory experiments, the quality of final effluent was monitored at NWRWRF and at two nearby wastewater treatment plants that currently use hypochlorite for disinfection. At these two facilities, pH of 7.0-8.0, chemical oxygen demand (COD) of 12-26 mg/L, alkalinity of 200-250 mg/L as CaCO3, chlorine residual of 1.5-6.0 mg/L, and total trihalomethanes of 100-190 ix μg/L (mostly chloroform) were observed. Conditions at NWRWRF were similar to those at Dale Mabry and River Oaks AWWTP, suggesting that chlorine demand and THM formation at NWRWRF would be similar to those at the two AWWTP, if chlorination is to be used. THM experimental results agreed with this suggestion.
Chlorine dose and temperature effects on the free chlorine residual and THMs production in NWRWRF filtered wastewater effluent were determined. Filtered effluent was collected and transported to USF laboratory where it was tested for 3 different chlorine doses (6 mg/L, 9 mg/L and 12 mg/L as Cl2) and 3 different temperatures (16°C, 23°C, and 30°C) at 7 different contact times (15, 30, 45, 60, 75, 90, and 120 min) in duplicate. The total number of batches prepared was: 3 different chlorine doses × 3 different temperatures × 7 different reaction times = 126 reactors.
According to Florida Administrative code 62-600.440, total chlorine residual should be at least 1 mg/L after a contact time of at least 15 min at peak hourly flow. Also, according to Florida Administrative code 62-600.440, if effluent wastewater has a concentration of fecal coliforms greater than 10,000 per 100 mL before disinfection, FDEP requires that the product of the chlorine concentration C (in mg/L as Cl2) and the contact time t (in minutes) be at least 120. Results showed that free chlorine residual was always above 1 mg/L in 15 min contact time for all chlorine doses and temperatures tested in this thesis. However, to be conservative, thesis conclusions and recommendations were based on the more stringent regulation: C*t ≥ 120 mg.min/L, assuming that the number of fecal coliform in NWRWRF wastewater effluent exceeds 10,000 per 100 mL prior to disinfection. The analysis showed that free chlorine residual for 6 mg/L was below the FDEP standard at all temperatures. At 16 °C and 23 °C, chlorine doses of 9 and 12 mg/L resulted in an appropriate free chlorine residual above the FDEP standard. However, a chlorine dose of 12 mg/L was resulting in high residual, which means high THM would be expected. Therefore, at 16 x and 23°C, 9 mg/L would be preferable. At 30 °C, only the chlorine dose of 12 mg/L met the standard at all contact times.
As expected, free chlorine residual decreased with an increase in temperature from 23°C to 30°C. Surprisingly, the residual at 16°C was lower than residual at 23°C. The production of THMs increased with higher contact time in all the experiments completed. Chlorine dose didn't have an effect on THM formation at 23°C, but it did at 30°C and 16°C, where THM concentrations were generally higher with the increase of chlorine dose. Temperature effect was noticed in most of the experiments, where THM production was usually higher at higher temperatures, except some cases where formation was similar for different temperatures. Chloroform, dichlorobromomethane, dibromochloromethane production ranges were respectively: 20-127 μg/L, 18-59 μg/L, and 3-7 μg/L. Bromoform concentrations were not observed in this experiment at any temperature or chlorine dose.
According to Florida Administrative code 62-302.530, Criteria for Surface Water Quality Classifications, the Florida Department for Environmental Protection (FDEP) set the following limits for THM concentrations in wastewater effluent to be as the following; 470 μg/L for chloroform, 22 μg/L for dichlorobromomethane, 34 μg/L for dibromochloromethane, and 360 μg/L for bromoform. Experimental results on NWRWRF filtered effluent showed that only dichlorobromomethane exceeded the limits set by FDEP at about 30 min contact time for all temperatures and chlorine doses tested. However, according to Florida Administrative code 62- 302-400, proposed changes to the code have set higher DCBM limit of 57 μg/L. Chlorination would be recommended at NWRWRF if the DCBM regulated limit increases to 57 μg/L. The recommended chlorine dose would be 9 mg/L for water temperatures around 16-23 °C and 12 mg/L for water temperatures around 30 °C
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Morgan, M. K., Phillip R. Scheuerman, C. S. Bishop, and Rebecca A. Pyles. "Teratogenic Potential of Atrazine and 2,4-D Using Fetax." Digital Commons @ East Tennessee State University, 1996. https://dc.etsu.edu/etsu-works/2871.
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The teratogenic potential of commercial formulations of atrazine (40.8%) and 2,4-D was evaluated using FETAX (frog embryo teratogenic assay--Xenopus). Because these herbicides have been detected in ground and surface water, this study was designed to determine the adverse effects in buffer and natural water for both herbicides. All treatments showed a significant concentration-response effect on exposed embryos, except for the 2,4-D natural water sample. Atrazine (solubility of the commercial formula used 70 mg/L at 20 degrees C), compared to 2,4-D (solubility = 311 mg/L at pH = 1 and 25 degrees C), had a significantly greater teratogenic effect in both the buffer (atrazine EC50 = 33 mg/L, LC50 = 100 mg/L, TI = 3.03; 2,4-D EC50 = 245 mg/L, LC50 = 254 mg/L, TI = 1.04) and natural water samples (atrazine EC50 < 8 mg/L, LC50 = 126 mg/L; 2,4-D EC50 and LC50 > 270 mg/L). The 2,4-D EC50 and LC50 values for the buffer were similar at 245 mg/L and 254 mg/L. These similar values and the teratogenic index (TI) of 1.04 suggested that 2,4-D was more embryotoxic than teratogenic to frog embryos at high concentrations. Atrazine in natural water demonstrated a significantly greater EC50 (100% abnormality at 8 mg/L, the lowest test concentration) to frog embryos than the buffer experiment (EC50 = 33 mg/L). The extrapolated lowest observable adverse effect concentration (LOAEC) for the natural water experiment was 1.1 mg/L. These results suggest that atrazine toxicity is enhanced by the synergistic or additive effects of some component of the water or atrazine was already present in the sample. In contrast to atrazine, 2,4-D was less toxic in natural water than buffer. These results suggest that both atrazine and 2,4-D pose little threat, since their embryotoxicity and teratogenicity to frog embryos occur at high concentrations approaching their maximum solubility levels in water.
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Zaragoza, Serrano Francisco José [Verfasser], and y. Barberà Lorenzo [Akademischer Betreuer] Brualla. "Monte Carlo estimation of absorbed dose distributions in water and anthropomorphic phantoms obtained from homogeneous and heterogeneous 106Ru eye plaques / Francisco José Zaragoza Serrano ; Betreuer: Lorenzo Brualla y Barberà." Duisburg, 2021. http://d-nb.info/1240145063/34.
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Plante, Ianik. "Développement de codes de simulation Monte-Carlo de la radiolyse de l'eau par des électrons, ions lourds, photons et neutrons applications à divers sujets d'intérêt expérimental." Thèse, Université de Sherbrooke, 2008. http://savoirs.usherbrooke.ca/handle/11143/4292.
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Water is a major component of living organisms, which can be 70-85% of the weight of cells. For this reason, water is a main target of ionizing radiations and plays a central role in radiobiology. Heavy ions, electrons and photons interact with water molecules; mainly by ionization and excitation. Neutrons interact with water molecules by elastic interactions, which generate recoil ions that will create ionizations and excitations in water molecules. These fast events (~10[superscript -12] s) lead to the formation of Reactive Oxygen Species (ROS). The ROS, in particular the hydroxyl radical (¨OH), interact with neighbour molecules such as proteins, lipids and nucleic acids by chemical interaction. Microbeams can irradiate selectively either the external membrane, the cytoplasm and the cell nucleus. These studies have shown that cell survival is greatly reduced when the nucleus is irradiated, but that this is not the case when cytoplasm or cell membrane is irradiated. Thus, DNA is a very sensitive site to ionizing radiation and ROS. For this reason, DNA has long been considered the most important molecule to explain radiobiological effects such as cell death. However, this concept has been challenged recently by new experimental results that have shown that cells which have not been directly in contact with radiation are also affected. This is called the bystander effect. Further studies have shown that a group of cells and their environment reacts collectively to radiation. A hypothesis put forward to explain this radiobiological phenomenon is that a irradiated cell will secrete signalling molecules that will affect non-irradiated cells. The implicated phenomenon and molecules are poorly understood at this moment. The purpose of this work is to improve our comprehension of the phenomenon in the microsecond that follows the irradiation. To these ends, a new Monte-Carlo simulation program of water radiolysis by photons has been generated. For photons of energy <2 MeV, they interact with water mainly by Compton and photoelectric effects, which create energetic electrons in water. The created electrons are then followed by our existing programs to simulate the radiolysis of water by photons. Similarly, a new code has been built to simulate the neutrons interaction with water. This code simulates the elastic collisions of a neutron with water molecules and calculates the number and energy of recoil protons and oxygen ions. The main part of this Ph.D. work was the generation of a non-homogeneous Monte-Carlo Step-By-Step (SBS) simulation code of non-homogeneous radiation chemistry. This new program has been used successfully to simulate radiolysis of water by ions of various LET, pH, ion types ([superscript 1]H[superscript +], [superscript 4]He[superscript 2+], [superscript 12]C[superscript 6+]) and temperature. The program has also been used to simulate the dose-rate effect and the Fricke and Ceric dosimeters. More complex systems (glycine, polymer gels and HCN) have also been simulated.
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Fuks, Josef. "Upravitelnost povrchových vod." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226152.
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The aim of the master´s thesis is the topic of the treatability of surface water with the focus on the process of suspension formation. For this work I took water samples from five different places around the Brno Dam which has contended with water quality deterioration for a long period. With these water samples, the series of jar coagulation tests were done with the application of three different commonly used coagulants. In the theoretical part of the master´s thesis I deal with the composition and attributes of surface water and the technology of its treatment. Each process of treatment is briefly described here with the emphasis on the process of suspension formation. The experimental part of the master´s thesis summarizes and presents the results gained through the coagulation tests in the laboratory. I evaluate the influence of different parameters on final effectiveness of water treatment and I try to find an optimal amount of coagulant, pH and speed of fast or slow mixing. Finally I compare the suitability of each coagulant and the influence of the sampling site on the effectiveness of water treatment.
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Ruiz, González Néstor A. "Use of GAFCHROMIC® EBT film for in-water measurements of surface dose, buildup region, and other dosimetric parameters of 6, 9, 12, 16, and 20 MeV electron beams a thesis /." San Antonio : UTHSC, 2008. http://learningobjects.library.uthscsa.edu/cdm4/item_viewer.php?CISOROOT=/theses&CISOPTR=38&CISOBOX=1&REC=1.
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Nasreddine, Abbas. "Alanine/EPR dosimetry for low to medium energy X-ray radiation processing control." Thesis, Strasbourg, 2020. http://www.theses.fr/2020STRAE025.
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L’irradiation par des rayons X de faible à moyenne énergie devient de plus en plus une technique répandue qui remplace des irradiations réalisées par des sources radioactives pour différentes applications telles que l’irradiation du sang, les traitements Sterile Insect Technology et la décontamination des produits alimentaires. Afin de s’assurer que la bonne dose est délivrée au produit, un dosimètre est placé sur ce dernier. Un type de dosimètres utilisé pour ces applications est le dosimètre à l’alanine, qui est équivalent à l’eau dans le cas des photons d’énergie supérieure à 200 keV. Cette thèse présente l’utilisation de l’alanine pour le control et la validation des process d’irradiations réalisés avec des rayons X de faible à moyenne énergie, ainsi que différentes méthodes développées pour déterminer des facteurs correctifs à appliquer à la réponse de ce dosimètre. Ces méthodes reposent sur des mesures expérimentales, des simulations Monte Carlo et des calculs analytiquesNowadays, low to medium energy X-ray irradiators are starting to replace irradiators using radioactivesources, mainly in the fields of blood irradiations, Sterile Insect Technique and food irradiations. A dosimeter is placed on the irradiated product to ensure that the desired dose is well delivered. One of the dosimetry systems that is used in radiation processing is the alanine/EPR dosimetry system. Alanine is considered as water equivalent, from a dosimetric point of view for photon energies that are higher than 200 keV. However, it loses its water equivalency for lower photon energies.This thesis presents the use of alanine for the control and validation of irradiation processes performed with low to medium energy X-rays, as well as different methods developed to determine corrective factors to be applied to the response of this dosimeter. These methods are based on experimental measurements, Monte Carlo simulations and analytical calculations
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Althanyan, Mohammed S. "Use of nanoemulsion liquid chromatography (NELC) for the analysis of inhaled drugs. Investigation into the application of oil-in-water nanoemulsion as mobile phase for determination of inhaled drugs in dosage forms and in clinical samples." Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5184.
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There has been very little research into the bioanalytical application of Microemulsion High Performance Liquid Chromatography (MELC), a recently established technique for separating an active pharmaceutical ingredient from its related substances and for determining the quantity of active drug in a dose. Also, the technique is not good at separating hydrophilic drugs of very similar chemical structures.
Different phase diagrams of oil (octane or ethyl acetate), co-surfactant (butanol), surfactant (sodium dodecyl sulphate (SDS) or Brij-35) and buffer (Phosphate pH 3) were developed and several nanoemulsion mobile phases identified. Nanoemulsion mobile phase that is, prepared with SDS, octane, butanol and a phosphate buffer, failed to separate hydrophilic compounds with a very close chemical structure, such as terbutaline and salbutamol. A nanoemulsion mobile phase containing a non-ionic surfactant (Brij-35) with ethyl acetate, butanol and a phosphate buffer, was, however, successful in achieving a base line separation, and the method was validated for simultaneous determination of terbutaline and salbutamol in aqueous and urine samples.
An oil-in-water (O/W) NELC method was developed and validated for the determination of formoterol in an Oxis® Turbuhaler® using pre-column fluorescence derivatisation. Although the same mobile phase was extended for separation of formoterol in urine, the formoterol peak¿s overlap with endogenous peaks meant that fluorescence detection could not determine formoterol in urine samples. Solid phase extraction, concentrating the final analyte 40 times, enabled determination of a low concentration of formoterol in urine samples by UV detection. The method was validated and an acceptable assay precision %CV <4.89 inter-day and %CV <2.33 intra-day was achieved. Then after the application of O/W nanoemulsion mobile phase for HPLC was extended for the separation of lipophilic drugs. The nanoemulsion liquid chromatography (NELC) method was optimised for the determination of salmeterol and fluticasone propionate in good validation data was achieved.
This thesis shows that, in general, the performance of O/W NELC is superior to that of conventional High Performance Liquid Chromatography (HPLC) for the analysis of both hydrophilic and lipophilic drugs in inhaled dosage formulations and urine samples. It has been shown that NELC uses cheaper solvents and that analysis time is faster for aqueous and urine samples. This considerable saving in both cost and time will potentially improve efficiency within quality control.
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Althanyan, Mohammed Saad. "Use of nanoemulsion liquid chromatography (NELC) for the analysis of inhaled drugs : investigation into the application of oil-in-water nanoemulsion as mobile phase for determination of inhaled drugs in dosage forms and in clinical samples." Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5184.
Full textAbstract:
There has been very little research into the bioanalytical application of Microemulsion High Performance Liquid Chromatography (MELC), a recently established technique for separating an active pharmaceutical ingredient from its related substances and for determining the quantity of active drug in a dose. Also, the technique is not good at separating hydrophilic drugs of very similar chemical structures. Different phase diagrams of oil (octane or ethyl acetate), co-surfactant (butanol), surfactant (sodium dodecyl sulphate (SDS) or Brij-35) and buffer (Phosphate pH 3) were developed and several nanoemulsion mobile phases identified. Nanoemulsion mobile phase that is, prepared with SDS, octane, butanol and a phosphate buffer, failed to separate hydrophilic compounds with a very close chemical structure, such as terbutaline and salbutamol. A nanoemulsion mobile phase containing a non-ionic surfactant (Brij-35) with ethyl acetate, butanol and a phosphate buffer, was, however, successful in achieving a base line separation, and the method was validated for simultaneous determination of terbutaline and salbutamol in aqueous and urine samples. An oil-in-water (O/W) NELC method was developed and validated for the determination of formoterol in an Oxis® Turbuhaler® using pre-column fluorescence derivatisation. Although the same mobile phase was extended for separation of formoterol in urine, the formoterol peak's overlap with endogenous peaks meant that fluorescence detection could not determine formoterol in urine samples. Solid phase extraction, concentrating the final analyte 40 times, enabled determination of a low concentration of formoterol in urine samples by UV detection. The method was validated and an acceptable assay precision %CV <4.89 inter-day and %CV <2.33 intra-day was achieved. Then after the application of O/W nanoemulsion mobile phase for HPLC was extended for the separation of lipophilic drugs. The nanoemulsion liquid chromatography (NELC) method was optimised for the determination of salmeterol and fluticasone propionate in good validation data was achieved. This thesis shows that, in general, the performance of O/W NELC is superior to that of conventional High Performance Liquid Chromatography (HPLC) for the analysis of both hydrophilic and lipophilic drugs in inhaled dosage formulations and urine samples. It has been shown that NELC uses cheaper solvents and that analysis time is faster for aqueous and urine samples. This considerable saving in both cost and time will potentially improve efficiency within quality control.
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Li, Zijian. "Analysis of Worldwide Pesticide Regulatory Models and Standards for Controlling Human Health Risk." Case Western Reserve University School of Graduate Studies / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=case1470137430.
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Fojtíková, Radka. "Vznik mikrosuspenze perikinetickou a ortokinetickou koagulací." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216203.
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This diploma thesis is focused on study of physico-chemical influences on model surface-water treatment which contain humic compounds. From those factors were monitored especially the dose of destabilizing reagent, pH value, temperature, velocity gradient of mixing and time of its duration. As destabilizing reagents were used Al2(SO4)3 .18H2O a Fe2(SO4)3 . 9H2O.
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KATSUOKA, LIDIA. "Avaliacao do impacto da atividade agropecuaria na qualidade da agua em areas de captacao superficial nas bacias hidrograficas dos rios Mogi - Guacu e Pardo, Sao Paulo." reponame:Repositório Institucional do IPEN, 2001. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10848.
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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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JESUS, SUELI C. de. "Levantamento dos niveis de radioatividade natural em aguas do Alto Vale do Ribeira a planicie costeira do litoral Sul do estado de Sao Paulo." reponame:Repositório Institucional do IPEN, 2010. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9598.
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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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SOUSA, KEILA C. P. M. de. "Estudo dos fluxos fluviais de isótopos naturais de rádio e bário dissolvido para as enseadas de Ubatuba, Litoral Norte do Estado de São Paulo." reponame:Repositório Institucional do IPEN, 2008. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11706.
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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
45
TEIXEIRA, WASHINGTON E. "Determinacao das concentracoes dos isotopos naturais de Ra em amostras costeiras do litoral norte do estado de Sao Paulo." reponame:Repositório Institucional do IPEN, 2004. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11173.
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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
46
Franck, Jerome Bruce. "Laser-induced desorption and damage of water- and heavy water-dosed optical thin films." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184882.
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Previous work has shown that laser-induced desorption (LID) can prove useful for the determination of surface contamination. However, because of the nature of small-spot sampling utilized in the previous work, it proved rather difficult to gather statistically significant data. A solution to this problem that still allowed sampling the surface with small focused laser spots was to automate the sample manipulation, laser control, and data acquisition of the system. With the automation of the LID facility in place, a detailed study of the LID of water/heavy water (H₂O/D₂O) was undertaken. As in the earlier work, samples were irradiated with a hydrogen fluoride/deuterium fluoride (HF/DF) laser beam focused inside an ultrahigh vacuum (UHV) chamber. The molecules desorbed from the sample surface were partially contained in a glass envelope that also contained a quadrupole mass analyzer. Samples consisted of bulk-etched CaF₂ and optical thin-film coatings of CaF₂--undosed or H₂O/D₂O dosed--on a variety of substrates. Some analysis was performed on cleaved, single-crystal alkali halides. The focused laser spot size was 155 μm (l/e² diameter) for the HF laser and 138 μm (l/e² diameter) for the DF laser. Between 400 and 800 sites per sample were tested for each desorption onset analysis. A study was also performed to test the possibility of correlation between (1) laser-induced damage and defects and (2) laser-induced desorption and adsorption sites for some of the samples listed above. Attempts to deuterate and hydrate CaF₂ thin films met with limited success as laser-induced desorption samples. Other analysis techniques showed that dosing during the coating process produced a more ordered coating; in fact, dosing with H₂O reduced the optical absorption in the "H₂O" band, modified the damage morphology, and, along with a low temperature bakeout, raised the laser-damage threshold.
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Lajhar, Fathi. "Electrospray for pulmonary drug delivery." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/electrospray-for-pulmonary-drug-delivery(b8aeaea9-9032-40f5-a8e0-b51c1ba8c8f8).html.
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Drug administration through the pulmonary route is an ancient technique that evolved from inhaling the smoke of certain leaves as a medicine. The optimum droplet diameter for the pulmonary system deposition has been identified to be in the range from 2 to 3.5 μm, with potential deposition rates of up to 80% of this size range. Currently, the most used aerosol generator methods are the pressurized metered dose inhalers. However, they generally exhibit low deposition efficiency with less than 20 % of the spray reaching the target area of the lungs as most of the drug deposited in the upper airways. This is for the most part due to the droplet size polydispersity that is inherent in these systems. The droplets of the biggest diameter will deposit in the upper airways, and then the deposited medicine will be swallowed and absorbed in the gastrointestinal tract. This can produce adverse medical side effects. Electrospray (ES) or electrohydrodynamic atomization (EHDA) is a promising atomization process due to its ability to produce a spray with monodisperse droplet size. The current study will investigate the feasibility of using electrospray in a pulmonary drug delivery system. Assessments, selection and characterization of suitable biocompatible solvents that can be used as a lung obstruction relief drug were carried out. Tests to identify the electrospray setup necessary to produce droplet sizes in the appropriate range for deposition in the lungs were carried out. The study found that both stable and pulsating cone jet modes can produce the required droplet size and the pulsating mode can produce at least four times higher flow than stable cone jet mode. A low-cost image analysis technique developed for this work gave satisfactory results that could be compared to droplet size scaling laws from the literature. However, it proved to be relatively time consuming and further automation of this technique would make it more suitable for large-scale studies. The image analysis results show a correlation between the cone length, cone angle and the applied voltage. The droplet scaling laws discrepancies such as the solution flow rate exponent and the constant that is used by some scaling laws may be attributed to the droplet evaporation time which is quite short for the water/ ethanol solutions. The emitter diameter and the conductivity effect on the I(Q) power law and the sensitivity of the onset voltage (Vonset) to the liquid flow rate (Q), were demonstrated for solutions of triethylene-glycol (TEG), and for an ethanol-water mixture solution.
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Matos, Rodolfo Rafael Andrade de. "Estimativa dos componentes azul e verde da pegada hídrica da batata-doce no agreste sergipano." Universidade Federal de Sergipe, 2016. https://ri.ufs.br/handle/riufs/6187.
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Among the various water use methods adopted by humanity, which uses more water is agriculture through irrigation procedure, allowing the crops in a larger space and being able to meet the demand for food both for human consumption as animal consumption. This work presents the concept of Water Footprint, which is the amount of water, directly and indirectly used in the production of a product. The water footprint is divided into three components: Green, Blue and Grey. The objective of this study was to determine the values of the water footprint of the blue and green components for the production of sweet potatoes through the traditional method using CROPWAT model during the years 2010, 2011 and 2012. The work developed in the Perimeter Irrigation Poção da Ribeira (PIPR) belongs to the Water Resources and Irrigation Development Company (COHIDRO), located in the municipalities of Itabaiana and Campo do Brito, Sergipe. The results showed that the Water Footprint Green in 2010, 2011 and 2012 was 494.75 (m³ / ton), 672.13 (m³ / ton) and 402.81 (m³ / ton) respectively. Have the Blue Water Footprint in 2010, 2011 and 2012 was 351.1 (m³ / ton), 448.4 (m³ / ton) and 570.06 (m³ / ton) respectively. The results showed no relationship between the average rates of crop yield with a higher consumption of water resulting in a higher Water Footprint, there is influence of precipitation on Water Footprint of sweet potato and that there is no direct relationship between productivity levels with weather variables used in calculations of the Water Footprint.Entre os diversos métodos de aproveitamento da água adotados pela humanidade, o que mais utiliza recursos hídricos é a agricultura através do procedimento da irrigação, permitindo os cultivos agrícolas em um espaço mais abrangente e sendo capaz de atender a demanda por alimentos tanto para consumo humano como consumo animal. Este trabalho apresenta o conceito de Pegada Hídrica (water footprint) que é a quantidade de água, direta e indiretamente, usada na produção de um produto. A pegada hídrica é dividida em três componentes: Verde, Azul e Cinza. O objetivo deste estudo foi determinar os valores da pegada hídrica dos componentes azul e verde para a produção da batata-doce através do método tradicional utilizando o modelo CROPWAT durante os anos de 2010, 2011 e 2012. O trabalho desenvolveu-se no Perímetro de Irrigação Poção da Ribeira (PIPR) pertencente à Companhia de Desenvolvimento de Recursos Hídricos e Irrigação (COHIDRO), localizado nos municípios de Itabaiana e Campo do Brito, em Sergipe. Os resultados obtidos evidenciaram que a Pegada Hídrica verde em 2010, 2011 e 2012, foi de 494,75 (m³/ton), 672,13 (m³/ton) e 402,81 (m³/ton) respectivamente. Já a Pegada Hídrica azul em 2010, 2011 e 2012 foi de 351,1 (m³/ton), 448,4 (m³/ton) e 570,06 (m³/ton) respectivamente. Os resultados obtidos mostraram que há relação entre os índices médios de produtividade da cultura com um maior consumo de água refletindo em maior Pegada Hídrica, que há influência da precipitação na Pegada Hídrica da batata-doce e que não há relação direta entre os índices de produtividade com as variáveis meteorológicas utilizadas no cálculos da Pegada Hídrica.
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BRITO, CARLOS F. de. "Avaliação dos efeitos da construção do rodoanel na qualidade da água e sedimento da Represa do Parque Pedroso, Santo André, SP. Estudo geoquímico de hidrocarbonetos policíclicos aromáticos (HPAs) metais e elementos traço com vistas ao abastecimento público." reponame:Repositório Institucional do IPEN, 2014. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11806.
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Tese (Doutorado em Tecnologia Nuclear)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Negrão, Sergio Garcia. "Determinação dos isótopos naturais de Rádio de meias-vidas longas, 226Ra e 228Ra, em águas minerais utilizadas nos balneários de Caxambú (MG) e Águas de Lindóia (SP)." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-03042012-083738/.
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Este trabalho teve por objetivos estudar a distribuição das concentrações de atividade dos isótopos de rádio de meias-vidas longas, 226Ra e 228Ra, em amostras de águas minerais coletadas no Balneário de Caxambu (MG) e no Balneário de Águas de Lindóia (SP). Foram observadas concentrações de atividade de 228Ra relativamente aumentadas em relação às de 226Ra nas águas minerais estudadas no Balneário de Caxambu. As concentrações elevadas de carbonatos e bicarbonatos destas águas podem resultar em um conseqüente aumento da solubilidade dos isótopos de Ra e pode ter um papel importante para a distribuição do 228Ra e para as reações de equilíbrio entre as fases sólida e líquida das soluções. No Balneário de Caxambu, as concentrações de atividade médias aritméticas variaram de 83 mBq L-1 a 3599 mBq L-1 e de 60 mBq L-1 a 4481 mBq L-1 para 226Ra e 228Ra, respectivamente. O maior valor de atividade de 226Ra foi observado nas águas da Fonte Venâncio, enquanto que a concentração máxima de 228Ra foi determinada na Fonte Ernestina Guedes. As razões de atividade 228Ra/ 226Ra variaram de 0,079 (Fonte Conde DEau e Princesa Isabel) a 4,2 (Fonte Mairink II). Em Águas de Lindóia as concentrações de atividade médias aritméticas variaram de 4,6 mBq L-1 a 41 mBq L-1 e de 30 mBq L-1 a 54 mBq L-1 para 226Ra e 228Ra, respectivamente. O maior valor de atividade de 226Ra foi observado nas águas da Fonte Engarrafada São Jorge, enquanto que a concentração máxima de 228Ra foi determinada na Fonte Santa Filomena (torneira pública 2). As razões de atividade 228Ra/ 226Ra variaram de 1,2 (Fonte Engarrafada São Jorge) a 9,1 (Fonte Engarrafada Jatobá 1). A exposição de indivíduos do público à radiação natural em virtude do consumo das águas minerais também foi avaliada neste trabalho. As doses efetivas foram estimadas utilizando-se um modelo dosimétrico conservativo, e integrando-se os resultados ao longo de 70 anos de vida de um indivíduo adulto, após a incorporação de 226Ra e 228Ra. Os resultados desta avaliação radiossanitária demonstraram que o nível de referência de dose efetiva comprometida recomendado pela Organização Mundial de Saúde de 0,1 mSv a-1 foi ultrapassado em quase todas as fontes de Caxambu, exceto para a Fonte Viotti, Fonte Dom Pedro e Fonte Dona Leopoldina. Em Águas de Lindóia e Lindóia as maiores doses efetivas comprometidas obtidas foram 8,4 10-3 mSv a-1 para o 226Ra (Fonte engarrafada São Jorge) e 2,6 10-2 mSv a-1 para o 228Ra (Fonte Santa Filomena torneira pública 2). Estes valores são menores que o limite recomendado pela Organização Mundial de Saúde. Doses efetivas comprometidas de até 7,4 x 10-1 mSv a-1 para o 226Ra (Fonte Venâncio, Caxambu) e 2,2 mSv a-1 para o 228Ra (Fonte Ernestina Guedes, Caxambu) foram estimadas no presente trabalho. No caso do 226Ra, este valor representa menos que 31% da dose efetiva média anual atribuída a radioatividade natural. Contudo, no caso do 228Ra, o limite anual de dose efetiva comprometida recomendado pela ICRP (considerando-se todas as fontes de exposição da população mundial à radiação) foi excedido não só na Fonte Ernestina Guedes, mas também na Fonte Beleza.The aim of this work was to study the long-lived Ra isotopes, 226Ra and 228Ra, natural distribution in mineral and spring waters from Caxambu (MG) and Águas de Lindóia (SP) waterparks. In Caxambu mineral waters it was observed 228Ra acitivity concentrations slightly higher than those of 226Ra. The elevated content of carbonates and bicarbonates of these waters can result in an increased solubility of the both Ra isotopes and may play an important role for the fate of 228Ra and its equilibrium distribution between solid and liquid phases. In Caxambu Thermal Spa, arithmetic mean activities ranged from 83 mBq L-1 to 3599 mBq L-1 and from 60 mBq L-1 to 4481 mBq L-1 for 226Ra and 228Ra, respectively. The highest 226Ra activity was found in Venancio Spring, while the maximum 228Ra activity value was determined in Ernestina Guedes. 228Ra/ 226Ra activity ratios varied from 0.079 (Conde DEau and Princesa Isabel Spring) to 4.2 (Mairink II Spring). In Águas de Lindóia, arithmetic mean activities ranged from 4.6 mBq L-1 to 41 mBq L-1 and from 30 mBq L-1 to 54 mBq L-1 for 226Ra and 228Ra, respectively. The maximum 226Ra activity concentration was found in the bottled mineral water São Jorge, while the higher 228Ra activity concentration was determined in Santa Filomena Spring (public station 2). 228Ra/ 226Ra activity ratios varied from 1.2 (bottled mineral water São Jorge) to 9.1 (bottled mineral water Jatobá 1). This work also performed the dose assessment due to the ingestion of 226Ra and 228Ra in Caxambu and Águas de Lindóia mineral and spring waters. The committed effective doses were estimated by using a conservative dosimetric model and taking into account the results over a lifetime (70 years) following intake of both long-lived Ra isotopes. The results from this radiological evaluation showed that the guindance committed effective dose level of 0.1 mSv y-1 recommended by World Health Organization was exceeded in almost all samples studied in Caxambu, except for Viotti Spring, Dom Pedro Spring and Dona Leopoldina Spring. In Águas de Lindóia and Lindóia, the highest committed effective doses estimated were 8.4 10-3 mSv y-1 for the intake of 226Ra (bottled mineral water São Jorge) and 2.6 10-2 mSv y-1 for 226Ra (Santa Filomena spring station 2). Both values are below the limit recommended by World Health Organization. The maximum commited effective doses per year obtained in this work were 7.4 10-1 mSv y-1 for 226Ra (Venancio Spring) and 2.2 mSv y-1 for 228Ra (Ernestina Guedes Spring). Considering the case of 226Ra intake via mineral water, the dose obtained represents less than 31 % of the average effective dose attributable annually from natural background radiation. However, in the case of 228Ra the annual committed effective dose limit recommended by ICRP (considering all sources of radiation exposure for the world population) was exceeded not only in Ernestina Guedes Spring, but also in Beleza Spring.