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1

Nelson, Andrew Wyatt. "Naturally occurring radioactive materials associated with unconventional drilling for natural gas". Diss., University of Iowa, 2016. https://ir.uiowa.edu/etd/5579.

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As unconventional drilling has emerged as a major industry in the US and around the world, many environmental health and pollution risks have surfaced. One emerging concern is the risk of environmental contamination arising from unconventional wastes that are enriched in naturally-occurring radioactive materials (NORM). Although NORM has been a well-documented contaminant of oil and gas wastes for decades, there are new challenges associated with unconventional drilling. This thesis discusses several of these challenges, focusing on NORM from black shale formations. Chapter 1 provides background information on environmental radioactivity and unconventional drilling. Chapter 2 describes the potential for NORM to migrate into groundwater around unconventional drilling operations. Chapters 3 and 4 describe radiochemical methods developed for the analysis of Marcellus Shale unconventional drilling wastes. Chapter 5 describes environmental partitioning of Marcellus Shale unconventional drilling wastes. Collectively, this thesis attempts to broaden the scientific understanding of NORM in unconventional drilling wastes so that potential environmental impacts may be mitigated.
2

Alharbi, Sami Hamad. "Measurements and monitoring of naturally occurring radioactive materials for regulation". Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/98122/1/Sami_Alharbi_Thesis.pdf.

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This project investigated the measurement of naturally occurring radioactive material. Such measurements are usually conducted to demonstrate compliance with the national and international requirements for radiation protection. The thesis reviewed the current regulation of these radioactive materials and identified the key regulatory challenges that relevant authorities face when implementing or establishing a regime for NORM. Limitations on the measurement of the release of radon (a radioactive gas) from surfaces were determined. The parameters influencing radon and thoron levels in indoor environments were investigated. The potential use of a broad energy germanium detector for the application of NORM was examined.
3

Larijani, C. "Production and evaluation of 236gNp and reference materials for naturally occurring radioactive materials". Thesis, University of Surrey, 2017. http://epubs.surrey.ac.uk/814166/.

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This thesis is based on the development of a radiochemical separation scheme capable of separating both 236gNp and 236Pu from a uranium target of natural isotopic composition (~1 g uranium) and ~200 MBq of fission decay products. The isobaric distribution of fission residues produced following the bombardment of a natural uranium target with a beam of 25 MeV protons has been evaluated. Decay analysis of thirteen isobarically distinct fission residues were carried out using high-resolution γ-ray spectrometry at the UK National Physical Laboratory. Stoichiometric abundances were calculated via the determination of absolute activity concentrations associated with the longest-lived members of each isobaric chain. This technique was validated by computational modelling of likely sequential decay processes through an isobaric decay chain. The results were largely in agreement with previously published values for neutron bombardments on natural uranium at energies of 14 MeV. Higher relative yields of products with mass numbers A~110–130 were found, consistent with the increasing yield of these radionuclides as the bombarding energy is increased. Using literature values for the production cross-section for fusion of protons with uranium targets, it is estimated that an upper limit of approximately 250 Bq of activity from the 236Np ground state was produced in this experiment. Using a radiochemical separation scheme, Np and Pu fractions were separated from the produced fission decay products, with analyses of the target-based final reaction products made using Inductively Couple Plasma Mass Spectrometry (ICP-MS) and high-resolution α and γ-ray spectrometry. In a separate research theme, reliable measurement of Naturally Occurring Radioactive Materials is of significance in order to comply with environmental regulations and for radiological protection purposes. The thesis describes the standardisation of three reference materials, namely Sand, Tuff and TiO2 which can serve as quality control materials to achieve traceability, method validation and instrument calibration. The sample preparation, material characterization via γ, α and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and the assignment of values for both the 4n Thorium and 4n + 2 Uranium decay series are presented.
4

Eitrheim, Eric Steven. "Characterization of wastes pertaining to naturally occurring radioactive materials (NORM) and the nuclear fuel cycle". Diss., University of Iowa, 2017. https://ir.uiowa.edu/etd/5464.

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Radioactive wastes from a range of sources are of great concern for their potential to negatively affect the environment and human health. There is a substantial need to develop new methods and techniques for management and disposal that are economically feasible and environmentally suitable. Such methods require better characterization and chemical understanding of these wastes, including advancements pertaining to the interaction between radioactive elements and non-radioactive constituents within the complex waste matrix. This thesis focuses on the fundamental chemistry of three types of waste forms: (1) solid drill cuttings from hydraulic fracturing activities; (2) Weapons grade plutonium; and (3) solid aluminum hydroxide phases associated with Hanford Tank wastes. The first study characterizes naturally occurring radioactive materials (NORM) in solid “drill cuttings” from hydraulic fracturing activities for natural gas extraction. NORM (uranium (U), thorium (Th), radium (Ra), lead (Pb), and polonium (Po) isotopes) associated with three samples from the Marcellus Shale formation were analyzed using radiometric techniques and found to have elevated radioactivity levels and isotopic disequilibria. NORM mobility within a landfill environment was also evaluated and these studies suggested some leaching of NORM from the solid waste form. Nuclear weapons technologies have also produced significant amounts of wastes, including some forms can be processed into useable, mixed-oxide (MOX) nuclear fuels. MOX solids require a complete separation of the gallium (Ga) originally present in the original weapons materials from Pu and other actinides to ensure the conversion was effective. A radiochemical method for the separation of Ga, Pu, U, Th, and americium (Am) was developed using chromatographic resins and radiochemical tracers. The innovation within this study included the novel use of 68Ga, an isotope developed for nuclear medicine applications. This research can be translated to nuclear forensics applications because it provides isotope ratios that can be used to determine the method or location of production of the original nuclear weapons material. The third research area focuses on the fundamental chemistry of the aluminum bearing wastes associated with the Hanford Site in Washington State. These mixed radioactive wastes have large quantities of aluminum (Al) that interferes with effective management and treatment strategies. There is a critical need to improve our fundamental understanding of Al chemistry in these systems to develop methods to improve our ability to work with the current waste streams. For example, Al is known to form oxyhydroxy polyaluminum species, or soluble molecular nanoclusters that exhibit different physical and chemical properties than isolated monomeric or dimeric forms of Al and contribute to much of the problematic chemistry in this system. There are significant challenges for the identification and characterization of these clusters in simple aqueous solutions and in more-complex solutions such as nuclear wastes. This body of work focuses on the isolation and identification of some of these clusters, including three Al30 clusters, and their interaction with other contaminants that are likely to be present in nuclear waste streams. Other clusters, including the elusive aluminum octamer, have also been synthesized and isolated, allowing for further characterization and understanding of these model clusters.
5

Liberati, Blake P. "Removal of Naturally Occurring Radioactive Material From Flowback/Produced Water From the Hydraulic Fracturing Process". Ohio University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1438968751.

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6

Frignani, Ilaria. "Tecniche di riduzione della quantità di rifiuti prodotti dall’attività di estrazione petrolifera e contenenti NORM (Naturally Occurring Radioactive Materials)". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.

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I rifiuti prodotti dall'estrazione petrolifera si presentano come incrostazioni o fanghi oleosi e viscosi, che si formano all'interno delle tubazioni e dei condotti nelle riserve petrolifere, soprattutto in prossimità di angoli e gomiti. Il loro contenuto radioattivo è di origine naturale ed è composto principalmente da Ra-226. A causa dell'elevata quantità di materiale che supera i valori limite di 10 Bq/g, i NORM (Naturally Occurring Radioactive Materials) rappresentano un notevole problema di rifiuto per l'industria petrolifera. In questo elaborato si descrivono le proprietà dei materiali NORM ed il metodo della riduzione del volume di incrostazione oleosa. Inoltre si sviluppa il metodo di digestione acida, analizzando i rifiuti NORM. Lo scopo delle attività di laboratorio è quello di cercare di ridurre la quantità dei rifiuti prodotti dall'estrazione di petrolio, concentrando la radioattività in un'unica fase. Una prova è stata svolta sul campione tal quale, mentre l'altra è stata eseguita sottoponendo il campione ad un pre-trattamento termico. Infine sono stati descritti alcuni metodi di smaltimento relativi ai rifiuti NORM.
7

Shams, Hasan M. "Determination of levels of naturally occurring radioactive materials in lagoon samples containing water from oil fields in the State of Kuwait". Thesis, University of Surrey, 2018. http://epubs.surrey.ac.uk/848601/.

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An evaluation of the specific activity concentrations associated with technologically enhanced naturally occurring radioactive materials (TENORM) and anthropogenic radionuclides has been undertaken, with particular focus on produced water from the Kuwait oil industry. This work is part of a systematic study to provide a radiological map of the outer boundary of the produced water lagoon located in the Minagish oil field in the south west region of the State of Kuwait. This particular lagoon contains material from the discharge of produced water which is a by-product of oil production in the region. The lagoon samples were prepared and placed into sealed, marinelli beakers for a full gamma-ray spectrometric analysis using a high-resolution, low-background, high-purity germanium detection systems at the University of Surrey Environmental Radioactivity Laboratory. Of particular interest are the calculation of the activity concentrations associated with members of the decay chains following decays of the primordial radionuclides of the 238U chain (226Ra, 214Pb, 214Bi) and the 232Th chain (228Ra, 228Ac, 212Pb, 212Bi, 208Tl), and the enhanced concentrations of radium isotopes. This thesis presents overview of the experimental samples which have been measured and the analysis techniques applied, including isotopic correlation plots across the sample region. The result shows the expected significant increase in 226Ra (and progeny) concentrations compared to the NORM values were taken from outside of the lagoon, with 226Ra activity concentrations ranging from approximately 10 Bq/kg to 2 kBq/kg from different samples. Radium equivalent and hazard indices are calculated for different regions of the pool boundary, with some regions have hardard indices greater than unity, and therefore constituting a potential radiological hazard. The analysis also investigates the correlations between members of the 232Th and 238U chain in these samples, and shows evidence for enhancement of radium isotopes (226Ra and 228Ra) in the lagoon produced water samples compared to the background levels.
8

Alazemi, Naser. "Determination of levels of naturally occurring radioactive materials in environmental samples in the State of Kuwait by high-resolution γ-ray spectrometry". Thesis, University of Surrey, 2015. http://epubs.surrey.ac.uk/807973/.

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A passively shielded, low-background hyper-pure germanium detector system was used to analyze and determine the radioactivity levels and content of soil samples taken from across the State of Kuwait. Samples were collected from 180 separate locations using a grid pattern with a 10km grid spacing with the result of creating a surface radiological map of the State of Kuwait. It was found that naturally occurring radioactive materials, 238U, 232Th and 40K, had average concentrations of 18.5±4.3, 17.1±4.1 and 410 ±110 Bq/kg respectively. Artificially created radionuclides were not found or were below the minimum level of detection. The Radium Equivalent Activity was determined to be 26.1±2.9 . Analysis was also carried out on isotopic abundances of uranium to determine any locations for evidence of enriched or depleted uranium deposits and/or elevated levels of 226Ra arising from fractionation effects. Typical elemental concentrations of uranium, uhorium and potassium in the samples across Kuwait were found to lie in the range 0.63±0.01 to 2.39±0.04 ppm, 1.34±0.03 to 6.70±0.11 ppm and 0.40±0.03 to 2.53±0.19 ppm respectively. Correlations between uranium, thorium and potassium abundances were measured, with clear correlations between the measured uranium and thorium elemental abundances.
9

Torres, Luisa Fernanda. "Holistic Risk Assessment of Surface Water Contamination by Naturally Occurring Radioactive Material in Oil Produced Water from the Bakken Shale". Thesis, North Dakota State University, 2016. https://hdl.handle.net/10365/28216.

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The risks to the environment and human health due to hydraulic fracturing (HF) in onshore unconventional oil and gas (O&G) development have been studied in the past but results are inconclusive. A common shortcoming in previous studies is the absence of social risk perception and awareness analysis. This thesis research proposes the combination of statistical methods to analyze risks to human health due to improper management of produced water, the major by-product of HF. This study focuses on the Bakken Shale located in North Dakota. A risk assessment of radium-226 was performed from a technical perspective only. A second assessment, focused on lead-210, combined technical analysis with risk perception and awareness of ND residents. Results indicate that the latter offers more holistic information that could greatly contribute to the mitigation of risks in O&G development by creation and implementation of standards and regulations that consider technical and social aspects.
Civil and Environmental Engineering Department; North Dakota Water Resources Research Institute Fellowship program; Industrial and Manufacturing Engineering Department; College of Engineering
10

Daggag, Dalia. "Computational Study on Binding of Naturally Occurring Aromatic and Cyclic Amino Acids with Graphene". DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 2019. http://digitalcommons.auctr.edu/cauetds/203.

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The knowledge on the conformations of amino acids is essential to understand the biochemical behaviors and physical properties of proteins. Comprehensive computational study is focused to understand the conformational landscape of three aromatic amino acids (AAAs): tryptophan, tyrosine, and phenylalanine. Three different density functionals (B3LYP, M06-2X and wB97X-D) were used with two basis sets of 6-31G(d) and 6-31+G(d,p) for geometry optimizations of the conformers of AAAs followed by the vibrational frequencies. The goal was to identify the right choice of density functional theory (DFT) level for conformational analysis of amino acids by comparing the computational data against the available experimental results. Calculated infrared (IR) frequency values indicated that wB97X-D/6-31+G(d,p) level is less favorable than other DFT levels in case of O-H and N-H stretching frequencies for the conformers of AAAs. The C=O stretching frequencies at different computational levels were in good agreement with the experimental results. Interactions of AAAs (tryptophan, tyrosine, and phenylalanine) and two cyclic amino acids (histidine and proline) individually with two finite-sized graphene sheets (C62H20 and C186H36) were explored using M06-2X/6-31G(d) level. Computational investigations of the binding of amino acids with graphene provide knowledge for designing of new graphene-based biological/biocompatible materials. Selected conformers for each amino acid with different orientations on the surface of graphene were examined. The purpose of computational study on graphene-amino acids interactions was to identify the preferred conformer of amino acid to bind on graphene as well as to find the influence of amino acid binding on the band gap of graphene. Different conformers of AAAs generally prefer parallel orientation through π-π interactions to bind with graphene. However, bent orientation is more preferred over parallel to bind on the surface of graphene in case of conformer having relative energy approximately equal to 5 kcal/mol for all three AAAs. Histidine generally exhibits higher binding affinity than proline to form complex with graphene. The binding energies in the aqueous medium were slightly lower than those obtained in the gas phase with some exceptions. The adsorption of amino acids did not affect the band gap of graphene.
11

Santawamaitre, Todsadol. "An evaluation of the level of naturally occuring radioactive materials in soil samples along the Chao Phraya river basin". Thesis, University of Surrey, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.555934.

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The aim of this study was to evaluate the level of natural radioactivity in river sediments and riverbank surface soils collected along the Chao Phraya River and its tributaries in Thailand. The activity concentrations of naturally occurring radioactive materials in the 238U and 232Th decay chains and from 40K were determined by means of a gamma-ray spectrometry system using a hyper-pure germanium (HPGe) detector in a low background configuration. The ranges of activity concentrations of 238U, 232Th and 40K were found to be 13.9 ± 0.4 ~ 76.8 ± 1.7, 12.9 ± 0.3 ~ 142.9 ± 2.8 and 178.4 ± 6.1 ~ 810.7 ± 26.7 Bq.kg-1, respectively. The results of this current study have been compared with the world mean values of 35, 30 and 400 Bq.kg-1, respectively, specified by the UNSCEAR (2000). The artificial radionuclide, 137Cs, was not observed in statistically significant amounts above the background level in the current study. Additionally, the -, distribution of the activity concentrations to various particle sizes of soil was . investigated in this current study. It can be assumed from the results that the grain size or the fraction of sand and clay content is one of the factors that affects the activity concentrations of 238U and 232Th in the soil samples, while only a weak correlation between the activity concentration of 40K and the particle size in soil samples was observed in this current study. Concerning radiological risk to human health, the absorbed gamma dose rate (D) in air at 1 metre above the ground surface was estimated to lie in the range 21.7±0.4 to 155.7±2.2 nGy.h-1; the outdoor annual effective dose equivalent (AEDE) was evaluated to vary from 26.6±0.4 to 190.9±2.7 ~SV.il, with the arithmetic mean value of 79.06±33.23 ~Svf\ which is comparable to the worldwide effective dose of 70~Svfl. Also, the values of the Raeq and the Hex for all soil samples in the present work are lower than the accepted safety limit value of 370 Bq.ki1 and below the limit of unity, respectively. The results indicate that the radiation hazard from primordial radionuclides in all soil samples from the area studied in this current work is not significant.
12

Peña, Gomez Natalie. "Development of polymeric and silica filtering materials functionalized with antimicrobial compounds for the elimination of microorganisms in liquid food". Doctoral thesis, Universitat Politècnica de València, 2020. http://hdl.handle.net/10251/137041.

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[ES] En la presente tesis doctoral se ha evaluado el uso de nuevos soportes celulósicos y silíceos como sistemas de filtración para la estabilización y conservación de alimentos líquidos con el fin de afrontar dos grandes retos de la industria de bebidas. Por un lado, evitar o minimizar los cambios en las propiedades nutricionales, estructurales y organolépticas de los alimentos, ocasionados por la pasteurización térmica tradicional, y ofrecer una alternativa al problema de la baja viabilidad debida a los altos costos de inversión/producción al aplicar nuevas tecnologías no térmicas. Por ello, esta tesis doctoral se centra en el desarrollo y evaluación de una nueva tecnología no térmica de conservación de alimentos líquidos basada en la filtración. Se han desarrollado sistemas de filtración a partir de soportes celulósicos y silíceos, sin funcionalizar o funcionalizados con compuestos antimicrobianos. En el primer capítulo se evaluó el uso de materiales de celulosa como soportes filtrantes para el tratamiento de alimentos líquidos. Como primera aproximación se desarrolló un material poroso nano-micro tubular a partir de la extracción y deslignificación del material celulósico presente en el corazón o raquis de la mazorca de maíz. El uso de este soporte resultó ser efectivo como material filtrante para el tratamiento de agua y zumo de naranja, en un sistema de flujo continuo, eliminando la carga microbiana. La aplicación de este soporte como sistema de filtración presenta diversas ventajas como su capacidad de retención microbiana, la reutilización de sub-productos del maíz y, por tanto, su respeto al medioambiente. Sin embargo, sería necesario optimizar el proceso de filtrado para evitar la frecuente obturación de sus poros que requirió varios ciclos de lavado durante el proceso, así como establecer un método de regeneración del material para incrementar su vida útil. Además, este sistema afectó al color del zumo filtrado, que no se mantuvo constante durante el proceso, lo que supone una importante desventaja que es necesaria abordar. Como segunda aproximación, se evaluó el potencial de la inmovilización de una molécula bioactiva sobre membranas de celulosa, para mejorar la capacidad de retención microbiana del material celulósico, así como permitir su reutilización. Los filtros de celulosa funcionalizados con poliaminas demostraron ser eficaces en la eliminación de patógenos en agua, debido a las cargas positivas generadas por los grupos amina inmovilizados en la superficie de las membranas, que atraen y retienen las bacterias cargadas negativamente. Dada la fácil preparación y procedimiento de uso de las membranas de celulosa funcionalizadas con poliaminas, éstas podrían ser consideradas una buena opción para el desarrollo de sistemas de tratamiento de aguas in situ, rápidos, de fácil manejo y de bajo coste. El segundo capítulo describe el desarrollo y aplicación de partículas de sílice funcionalizadas con compuestos de aceites esenciales, con el fin de diseñar coadyuvantes de filtración con actividad antimicrobiana. La filtración de diversas matrices alimentarias (agua, cerveza y zumo de manzana) a través de los soportes funcionalizados con los antimicrobianos naturales demostró ser eficaz en la reducción del recuento de la cepa patógena Escherichia coli, así como frente a la microflora endógena de la cerveza y el zumo (bacterias acidolácticas, aerobios mesófilos, psicrófilos, mohos y levaduras). La eficacia en el control microbiano se debe a la combinación de la adsorción física y la inactivación por contacto con los compuestos de aceites esenciales inmovilizados. Además, la evaluación de las propiedades físico-químicas y sensoriales de los alimentos líquidos demostró un efecto poco significativo, éste depende del tamaño de las partículas de sílice usadas y de la molécula bioactiva inmovilizada. Por lo tanto, el sistema de conservaci�
[CAT] En la present tesi doctoral s'ha avaluat l'ús de nous suports cel·lulòsics i silicis com a sistemes de filtració per a l'estabilització i conservació d'aliments líquids, amb la finalitat d'afrontar dos grans reptes de la indústria de begudes. D'una banda, evitar o minimitzar els canvis en les propietats nutricionals, estructurals i organolèptiques dels aliments, ocasionats per la pasteurització tèrmica tradicional, i oferir una alternativa al problema de la baixa viabilitat deguda als alts costos d'inversió/producció en aplicar noves tecnologies no tèrmiques. Per això, aquesta tesi doctoral es centra en el desenvolupament i avaluació d'una nova tecnologia no tèrmica de conservació d'aliments líquids basada en la filtració. S'han desenvolupat sistemes de filtració a partir de suports cel·lulòsics i silicis, sense funcionalitzar o funcionalitzats amb compostos antimicrobians. En el primer capítol es va avaluar l'ús de materials de cel·lulosa com a suports filtrants per al tractament d'aliments líquids. Com a primera aproximació es va desenvolupar un material porós nano-micro tubular a partir de l'extracció i deslignificació del material cel·lulòsic present en el cor o raquis de la panolla de dacsa. L'ús d'aquest suport va resultar ser efectiu com a material filtrant per al tractament d'aigua i suc de taronja, en un sistema de flux continu, eliminant la càrrega microbiana. L'aplicació d'aquest suport com a sistema de filtració presenta diversos avantatges com la seua capacitat de retenció microbiana, la reutilització de subproductes de la dacsa i, per tant, el seu respecte al medi ambient. No obstant això, seria necessari optimitzar el procés de filtrat per a evitar la freqüent obturació dels seus porus que va requerir diversos cicles de rentada durant el procés, així com establir un mètode de regeneració del material per a incrementar la seua vida útil. A més, aquest sistema va afectar el color del suc filtrat, que no es va mantenir constant durant el procés, la qual cosa suposa un important desavantatge que és necessari abordar. Com a segona aproximació, es va avaluar el potencial de la immobilització d'una molècula bioactiva sobre membranes de cel·lulosa, per a millorar la capacitat de retenció microbiana del material cel·lulòsic, així com permetre la seua reutilització. Els filtres de cel·lulosa funcionalitzats amb poliamines van demostrar ser eficaces en l'eliminació de patògens en aigua, a causa de les càrregues positives generades pels grups amina immobilitzats en la superfície de les membranes, que atrauen i retenen els bacteris carregats negativament. Donada la fàcil preparació i procediment d'ús de les membranes de cel·lulosa funcionalitzades amb poliamines, aquestes podrien ser considerades una bona opció per al desenvolupament de sistemes de tractament d'aigües in situ, ràpids, de fàcil maneig i de baix cost. El segon capítol descriu el desenvolupament i aplicació de partícules de sílice funcionalitzades amb compostos d'olis essencials, amb la finalitat de dissenyar coadjuvants de filtració amb activitat antimicrobiana. La filtració de diverses matrius alimentàries (aigua, cervesa i suc de poma) a través dels suports funcionalitzats amb els antimicrobians naturals va demostrar ser eficaç en la reducció del recompte del cep patogen Escherichia coli, així com enfront de la microflora endògena de la cervesa i el suc (bacteris àcid làctics, aerobis mesòfils, psicròfils, floridures i llevats). L'eficàcia en el control microbià es deu a la combinació de l'adsorció física i la inactivació per contacte amb els compostos d'olis essencials immobilitzats. A més, l'avaluació de les propietats fisicoquímiques i sensorials dels aliments líquids estudiats va demostrar un efecte poc significatiu, aquest depèn de la grandària de les partícules de sílice usades i de la molècula bioactiva immobilitzada. Per tant, el sistema de conserv
[EN] In the present doctoral thesis the use of new cellulosic and silica supports as filtering systems for the stabilization and preservation of liquid foods has been evaluated to overcome two major challenges of the beverage industry. On the one hand, avoid or minimize the changes in the nutritional, structural and organoleptic properties of food caused by traditional thermal pasteurization, and offer an alternative to the problem of low viability due to high investment/production costs when applying new non-thermal technologies. Therefore, this doctoral thesis focuses on the development and evaluation of a new non-thermal technology for the preservation of liquid foods based on filtration. The filtering systems have been developed from cellulosic and silica supports, non-modified or functionalized with antimicrobial compounds. In the first chapter, the use of cellulose materials as filtering supports for the treatment of liquid foods was evaluated. As first approximation, a porous nano-micro tubular material was developed from the extraction and delignification of the cellulosic material present in the corn stalk. The use of this support was effective as filtering material for the treatment of water and orange juice, in a continuous flow system, eliminating the microbial load. The application of this support as filtering system has several advantages, such as its microbial retention capacity, the reuse of corn by-products and, therefore, its respect for the environment. However, it would be necessary to optimize the filtering process to avoid the frequent clogging of its pores that required several washing cycles during the process, as well as to establish a method of material regeneration to increase its life. In addition, this system affected the color of the filtered juice, which did not remain constant during the process, representing an important disadvantage that must be addressed. As a second approach, the potential of the immobilization of a bioactive molecule on cellulose membranes was evaluated to improve the microbial retention capacity of the cellulosic material, as well as to allow its reuse. The cellulose filters functionalized with polyamines proved to be effective in eliminating pathogens in water, due to the positive charges generated by the amine groups immobilized on the surface of the membranes, which attract and retain the negatively charged bacteria. Given the easy preparation and usage of the polyamines-functionalized cellulose membranes, these could be considered a good option for the development of fast, easy to use and low cost in situ water treatment systems. The second chapter describes the development and application of silica particles functionalized with essential oil components to design filtering aids with antimicrobial activity. The filtration of various food matrices (water, beer and apple juice) through the supports functionalized with natural antimicrobials proved to be effective in reducing the load of the pathogenic strain Escherichia coli, as well as reducing the endogenous microflora of beer and the juice (lactic acid bacteria, mesophilic, psychrophilic, mold and yeast). The removal capability is due to the combination of physical adsorption and contact inactivation with the essential oil compounds immobilized. In addition, the evaluation of the physicochemical and sensory properties of the liquid foods studied showed a not significant effect, it depends on the size of the silica particles used and the immobilized bioactive molecule. Therefore, the proposed preservation system has a high potential for cold beverage pasteurization processes.
N. Peña-Gomez would like to thank for financial support in the frame of her PhD project to Operational Programme of the European Social Fund (ESF) 2014-2020, the Agencia Estatal de Investigación, Generalitat Valenciana and FEDER-EU (Projects RTI2018-101599-B-C21 and AGL2015-70235-C2-1-R). The authors also thank the Electronic Microscopy & Microanalysis Laboratory at Patras University for support.
Peña Gomez, N. (2020). Development of polymeric and silica filtering materials functionalized with antimicrobial compounds for the elimination of microorganisms in liquid food [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/137041
TESIS
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Motimedi, T. C. "Evaluation of soil to plant transfer factors of naturally occurring radioactive materials (norms) in some vegetables / T.C Motimedi". Thesis, 2012. http://hdl.handle.net/10394/15769.

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Bahmaid, Mohammad A. "Application of the gamma pathway exemption rule for naturally occurring radioactive materials in industrial waste using ISOSHLD-II". Thesis, 1995. http://hdl.handle.net/1957/34658.

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Shiau, Tz-Jau, i 蕭子昭. "Feasibility Study Of Polyhydroxyalkanoates Production For Materials Recycling Using Naturally-occurring Pollutant Degraders". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/63362230681898030492.

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Streszczenie:
碩士
國立宜蘭大學
化學工程與材料工程學系碩士班
100
Considering eco-friendliness of recycling and reuses of biomaterials for sustainable development, this first-attempt study used indigenous pollutant degrading bacteria for the production of biodegradable polymers polyhydroxyalkanoates (PHAs) during wastewater treatment. First, the candidate strains of poly-3-hydroxybutyrate (PHB) production were inspected among isolated pollutant-degrading microbes via Sudan black B staining (SB staining). Next, according to batch cultures using lauric acid (C12) as the sole carbon source for PHB production, the promising PHB-generating strains were obtained via comparative analysis upon the characteristics of cell growth and/or PHB production. Our findings indicated that Aeromonas hydrophila NIU01 cultured at 10 g L-1 lauric acid-supplemented medium could generate intracellular PHB content at ca. 36.02 wt%. At optimal concentration of lauric acid, cultures containing dyes or amines at different concentrations were conducted to simulate of microbial production PHB in parallel with dye decolorization. Here, our finding indicated that strains NIU01 could significantly tolerate dye pollutant(s) and aromatic amines for cell growth and PHB-production, suggesting promising feasibility to be used for simultaneous PHB production and wastewater decolorization. In addition, dye-decolorized wastewaters (WWs) were used as carbon source for batch cultivation. With CO2 respirometer analysis, inhibitory effects of WW on microbial growth and PHAs-generating capabilities were disclosed to reveal the feasibility of materials recycling and reuses during WW treatment. Follow-up studies also inspected the economic-viability of using various industrial WWs for PHAs production for practical industrial applications. This study also isolated functioning microorganisms from guts of indigenous earthworm Eisenia fetida for production of green biopolymer materials and explored the feasibility of simultaneous dye-bearing wastewater treatment and production of biodegradable polymer PHAs. After serial acclimation to evolve most stable microbial decolorizes, lauric acid-bearing batch cultures of these consortia were conducted in nutrient-limiting conditions to evaluate efficiencies of PHB production. These strains were found to be EPMG01, EPMG02, EPMG03, ESB01 and ESB03, indicating the promising feasibility of simultaneous generation of biopolymer PHAs and industrial dye-wastewater treatment.
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Leopold, Karsten [Verfasser]. "Chemical types of bounding of natural radionuclides in TENORM : (technologically enhanced naturally occuring radioactive materials) / presented by Karsten Leopold". 2007. http://d-nb.info/988995603/34.

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