Teses / dissertações sobre o tema "Contamination de surfaces – Nettoyage"
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Abbadie, Alexandra. "Nettoyage chimique humide de surfaces silicium (appliqué au recyclage), nettoyage chimique humide et préparation de surface d'alliages silicium-germanium et de couches de germanium pur". Toulouse 3, 2004. http://www.theses.fr/2004TOU30082.
Texto completo da fonteMettler, Eric. "Etude des caractéristiques microbiologiques et physico-chimiques, après nettoyage et désinfection, de surfaces colonisées par des biofilms, dans divers ateliers de l'industrie alimentaire et au laboratoire". Dijon, 1996. http://www.theses.fr/1996DIJOS067.
Texto completo da fonteLelièvre, Caroline. "Nettoyabilité d'équipements fermés agro-industriels : modélisation des cinétiques de nettoyage de surfaces contaminés par des spores de Bacillus et caractérisation de l'influence de l'hydrodynamique". Compiègne, 2001. http://www.theses.fr/2001COMP1355.
Texto completo da fonteDari, Carolina. "New innovative methods for cleaning surfaces using foams based on bio-based surfactants". Electronic Thesis or Diss., Université de Lille (2022-....), 2024. http://www.theses.fr/2024ULILR038.
Texto completo da fonteIn the food industry, surfaces contaminated with microorganisms are a major cause of cross-contamination, resulting in foodborne illness and food waste. Despite thorough cleaning efforts, foodborne illness rates are rising, suggesting current practices are insufficient. Traditional cleaning methods also consume large amounts of water, energy, and chemicals, raising sustainability and environmental concerns. The industry is exploring more sustainable alternatives, such as dry-cleaning methods, eco-friendly products, and advanced control systems, to reduce resource consumption while maintaining hygiene standards. One promising alternative for cleaning closed surfaces is the use of foam, a method already used for open surfaces. Foam cleaning can potentiallyreduce water, energy, and chemical consumption. The aim of this thesis is to study the links between foam properties and removal of microorganisms from both open and closed surfaces, and explores innovative cleaning techniques to develop more sustainable and efficient methods for the food industry.The first part is dedicated to the cleaning of open surfaces, i.e., static foam cleaning. Here we study the removal of hydrophilic and hydrophobic Bacillus subtilis spores from stainless steel surfaces by using foams. The model foams are formulated with bio-based surfactants (10-hydroxystearic acid and sodium cocoyl isethionate). The relationship between bubbles size and foam liquid fraction and the decontamination efficiency is investigated to determine the mechanisms of foam action. Foams themselves can decontaminate surface soiled with spores, most probably by wiping and imbibition mechanisms. Foams with smaller bubbles size have the highestdecontamination efficiency. Under the conditions studied, the liquid fraction is not the main parameter governing the decontamination efficiency.The second part is dedicated to the cleaning of closed surfaces, i.e., foam flow cleaning. Here we study the efficiency of foam flow formulated with a model surfactant (Sodium dodecyl sulfate) in comparison with foam flow formulated with bio-based surfactants (alkyl polyglucosides) to remove hydrophilic spores from pipes. We demonstrate similar efficiency for short cleaning times). In addition, through a life cycle assessment we demonstrate the reduction of several environmental impacts with the use of bio-based surfactant compared to the model surfactant.The third part is dedicated to the stabilization of water-in-water emulsions and the production of a foamulsion based ont these emulsions. We study the stabilization of PEG-in-Dextran emulsions with lamellar gel networks based on alkyl polyglucosides and fatty alcohols. We show that highly stable emulsions are obtained over a long period of time for specific formulation conditions. We also demonstrate for the first time the production of a foamulsion based on water-in-water emulsions
Tauveron, Grégoire. "Propriétés de surface des spores de Bacillus cereus et capacité de contamination des équipements agro-industriels : influence des conditions environnementales". Compiègne, 2006. http://www.theses.fr/2006COMP1650.
Texto completo da fonteBacillus cereus, responsible for food toxi-infections, frequently contaminates heated-processed foods. Indeed, beyond its resistance to heat and chemical treatment, the B. Cereus spore possesses a strong capacity to adhere to inert materials such as steel and therefore may be considered as a major food contamination risk. Mastery of equipment hygiene requires a deeper knowledge of factors which influence B. Cereus spores' adhesion capacity and their resistance to cleaning techniques. The adhesion of micro-organisms is linked to their surface properties, which may vary according to the environmental conditions they encounter. Ln the course of this study, we reveal a wide variability in surface properties (morphology, hydrophobia, surface protein content) from one spore strain to another. These differences are associated with a significant variability in each strain's capacity to adhere to steel and in its resistance to cleaning-in-place (CIP). Close examination of these data has shown that the longer their appendages, the stronger the spores' adhesion, whereas resistance to cleaning-in-place is inversely proportional to the size of the exosporia. The use of mutants (from B. Cereus and B. Anthracis) allowed us to show that brush-like exosporial filaments (made up of BclA) inhibit resistance to cleaning. An absence of the ExsY protein stops the exosporium from developing and leads to a consequent decrease in adhesion and an increase in resistance to cleaning. Thus, surface contamination risk is higher for strains with long appendages and small exosporia. Furthermore, spores' surface properties are affected by the conditions encountered by the bacteria. We have studied the influence of conditions likely to be encountered by spores in the agro-food industry. Sporulation at high temperature and sporulation in a liquid environment respectively affect the exosporium's size and integrity and result in lesser adhesion. Ln addition, the application of hydrodynamic conditions close to those encountered in the agro-food industry, induces greater or lesser damage to the exosporia according to the conditions in which they sporulated. This damage leads to a decrease in spore adhesion coupled with an increase in their resistance to eleaning. These behavioural differences must therefore be taken into account in analytical procedures applied in the determination of risk associated with the presence of B. Cereus
Negri, Fabienne. "Traitement des plaquettes de GaAs (100) de grand diamètre : mise au point du procédé, préparation et caractérisations de surface pour l'épitaxie par jets moléculaires". Toulouse 3, 2001. http://www.theses.fr/2001TOU30208.
Texto completo da fonteFeve, Séverine. "Validation du nettoyage appliquée à du matériel de développement industriel". Bordeaux 2, 2000. http://www.theses.fr/2000BOR2P055.
Texto completo da fonteDoumbia, Faman. "Étude du nettoyage de surfaces encrassées par des produits carnés". 63-Aubière : Impr. U.E.R. Sci, 1985. http://catalogue.bnf.fr/ark:/12148/cb36110021j.
Texto completo da fonteSergent, Delphine. "Validation d'un système de nettoyage automatique". Bordeaux 2, 2000. http://www.theses.fr/2000BOR2P071.
Texto completo da fonteCôte, Sophie. "Validation de procédures de nettoyage dans un laboratoire industriel de recherche et développement galénique". Paris 5, 1994. http://www.theses.fr/1994PA05P172.
Texto completo da fonteHody, Virginie. "Préparation de surfaces industrielles par plasmas froids : contribution à l'étude des mécanismes élémentaires d'interaction entre une post-décharge N2-O2 et l'hexatriacontane". Vandoeuvre-les-Nancy, INPL, 2004. http://www.theses.fr/2004INPL105N.
Texto completo da fonteThe presented works deal with preparation of industrial surfaces and more particularly with surface cleaning by plasma. In order to clarify the role played by the different active species during the surface cleaning, we studied the mechanisms of interaction between Nz-Oz post-discharges and hexatriacontane. The hexatriacontane modifications have been brought to the fore by means of numerous analytical techniques (weighing, elementary chemical analysis, Fourier transformed infrared analysis, size exclusion chromatography analysis). We studied also the gas phase by optical emission spectroscopy and determined the concentrations of atomic oxygen and nitrogen by NO titration for some gas mixtures. The correlation of these experimental results with the modeling results of the post-discharge permitted to determine precisely what are the species and the reactional mechanisms which take place during the fonctionnalisation and the grafting of the polymer. Owing to the conclusions obtained during these basic studies, it was possible to apprehend more easily the three industrial problematics submitted as a part of the TIAG ministerial project. Then we have studied the surface preparation of copper samples by radio-frequency and pulsed DC plasmas, the surface preparation of samples in copper-lead alloy by pulsed DC plasmas and finally, the elimination by pulsed DC plasmas of the contaminants which can sweat from polycarbonate and polysulfone samples
Attal, Yasser. "Optimisation d'un procédé de nettoyage et de décontamination des surfaces métalliques par laser : conception d'un système laser associé". Châtenay-Malabry, Ecole centrale de Paris, 1998. http://www.theses.fr/1998ECAP0639.
Texto completo da fonteGauthier, Dominique. "Contribution à l'étude de la contamination bactérienne des respirateurs". Bordeaux 2, 1993. http://www.theses.fr/1993BOR2P118.
Texto completo da fonteLatrubesse, Anne. "Validation des procédures de nettoyage d'une turbine Glatt". Bordeaux 2, 1992. http://www.theses.fr/1992BOR2P074.
Texto completo da fonteWilliamson, Becky. "Mechanisms of fixed contamination of commonly engineered surfaces". Thesis, Lancaster University, 2018. http://eprints.lancs.ac.uk/127789/.
Texto completo da fonteGuillet, Karelle. "Hygiène industrielle : maîtrise de l'environnement dans un établissement pharmaceutique". Bordeaux 2, 1999. http://www.theses.fr/1999BOR2P084.
Texto completo da fonteCalendreau, Christelle. "Validation du nettoyage du matériel de production d'un laboratoire pharmaceutique". Bordeaux 2, 1995. http://www.theses.fr/1995BOR2P094.
Texto completo da fonteNoel, Cédric. "Plasmas micro-ondes d'argon à la pression atmosphérique : diagnostics et applications au nettoyage de surfaces". Thesis, Vandoeuvre-les-Nancy, INPL, 2009. http://www.theses.fr/2009INPL020N/document.
Texto completo da fonteThe present work deals with the study of argon microwave plasmas generated in resonant cavity at atmospheric pressure and their application to surface cleaning. First, a study of the aim of surface cleaning of industrial surfaces is presented, followed by a state of the art of existing solutions and their limitations, showing the interest of plasmas as an alternative, especially atmospheric pressure microwave resonant cavity plasmas. In the case of argon, these plasmas have the particularity to be inhomogeneous and constituted of one or many small diameter filaments, depending on experimental conditions. The study of the filamentation of these discharges is the subject of the second chapter. In the case of one filament, correlations have been evidenced between its size, its temperature and the dissipated power. A simple electromagnetic simulation allowed us to describe the influence of the main plasmas parameters on the filamentation process. The third chapter presents results from the characterisation of a single argon filament by the mean of diode laser absorption in continuous and pulsed plasma mode. The effect of oxygen addition is also studied. The last chapter deals with the study of the use of atmospheric pressure microwave post-discharges in argon-nitrogen or argon-oxygen mixtures for surface cleaning application. We studied the interaction of such post-discharges with model organic molecules (stearic acid and 1-octadecene). Surface analyses by the mean of extreme surface analysis techniques based on mass spectrometry (ToF-SIMS and FTMS) allow us to improve our understanding of cleaning mechanisms
Noël, Cédric Belmonte Thierry. "Plasmas micro-ondes d'argon à la pression atmosphérique diagnostics et applications au nettoyage de surfaces /". S. l. : S. n, 2009. http://www.scd.inpl-nancy.fr/theses/2009_NOEL_C.pdf.
Texto completo da fonteDecraene, Valerie. "Light-activated antimicrobial coatings for reducing microbial contamination of surfaces". Thesis, University College London (University of London), 2008. http://discovery.ucl.ac.uk/1446168/.
Texto completo da fonteJacquin, Daniel. "Diagnostics et modélisation d'un plasma multipolaire d'hydrogène utilisé dans le nettoyage de surfaces d'arséniure de gallium". Paris 11, 1988. http://www.theses.fr/1988PA112193.
Texto completo da fonteLissonde, Anne. "Validation du nettoyage d'une chaine de production aprés fabrication d'un produit antimitotique". Bordeaux 2, 1994. http://www.theses.fr/1994BOR2P069.
Texto completo da fonteChen, Bowei. "Détection du facteur d'encrassement par onde de coda ultrasonore lors de la contamination et le nettoyage d'un substrat solide". Thesis, Valenciennes, 2019. http://www.theses.fr/2019VALE0016.
Texto completo da fonteFouling of equipment occurs in many industrial sectors. For example, contamination of surfaces in contact with foodstuff, caused by fouling, causes considerable economic losses and increases public health risks. The cleaning of the fouled surface is generally carried out using highly polluting chemicals. Therefore, it is important to develop devices to monitor the formation / removal of fouling on these surfaces (without disrupting production) in order to reduce the microbiological risks and environmental/economic impacts associated with the cleaning processes. In this work, the detection of fouling factor using a noninvasive ultrasonic method, called "coda wave interferometry", abbreviated in English (CWI), was investigated. This technique has been tested for various types of applications (wax cleaning, biofilm formation detection and protein deposit cleaning). The results obtained are very promising and show that the CWI is able to detect even a slight change in the fouling factor. In particular, the evolution of the decorrelation coefficient for each application shows good agreement with the actual fouling factor. Overall, this work has provided evidence that the CWI method is applicable to the monitoring of fouling factor of solid surfaces
Saucedo-Alderete, Raúl O. "Post-harvest spray treatments to reduce Salmonella contamination on cantaloupe surfaces". Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/51831.
Texto completo da fontePh. D.
Richard, Marlène. "Nettoyage des surfaces métalliques vis-àvis des protéines et du risque prion : Etudes des interfaces protéines/métal". Ecully, Ecole centrale de Lyon, 2006. http://bibli.ec-lyon.fr/exl-doc/mrichard.pdf.
Texto completo da fonteCleaning of reusable medical devices is essential and must be effective before sterilization or disinfection. At the present time, few methods are available to evaluate the effectiveness of cleaning with respect to organic soils. With the emergence of the prion risk and the exceptional resistance of this infectious agent to the conventional disinfection procedures, a special attention is paid to the detergency of the proteinic soils. Moreover, the treatment processes currently recommended for prion inactivation are extremely drastic and cannot be applied to the thermosensitive medical devices. In this context, the development of effective formulations or processes seems to be a real need and constitutes the goal of this study. Initially, we set up a system allowing an evaluation of formulation and/or process performances with respect to proteinic soils adsorbed on stainless steel surfaces. This system is based on the use of the X ray photoelectron spectroscopy (XPS) and of protein radioloabelling techniques by 125 iodine. The performances of five formulations could be established and treated on a hierarchical basis making it possible to validate the reliability of this system. Next, our efforts were concentrated on the prion risk with the development of a biochemical method of indirect detection of the residual protein prion (PrP) on stainless steel support. The implementation of this method enables us to propose an effective process of cleaning in vitro with respect to protein prion, and this independently of the types of human protein prion or the animal stains used. Nevertheless, we showed that the lipidic environment of proteins significantly facilitated the cleaning process effectiveness and that the exclusively proteinic soils were resistant. This process will have to be validated by inoculation to animal. Convinced of the interaction forces governing the protein adsorption on metal surfaces, we wished to study in situ formation of the interfaces proteins/metal by XPS. Thus, chemical modifications of protein were observed in the interfaces formed with chromium, the oxide chromium and gold, by protein metallization. Although these conditions are not representative of the physiological conditions, we think that these data underline the chemical nature of the proteins/metal interactions and translate the protein resistance to the cleaning processes
Raynaud, Patrice. "Nettoyage de surfaces de silicium par plasma (PMM) d'argon et d'hydrogène : étude de la désorption de l'hydrogène". Grenoble 1, 1991. http://www.theses.fr/1991GRE10135.
Texto completo da fonteRichard, Marlène Martin Jean-Michel. "Nettoyage des surfaces métalliques vis-àvis des protéines et du risque prion Etudes des interfaces protéines/métal /". [S.l.] : [s.n.], 2006. http://bibli.ec-lyon.fr/exl-doc/mrichard.pdf.
Texto completo da fonteEl, Ghzaoui Abdeslam. "Evaluation de la contamination minérale et organique ; application au lavage d'une surface polymérique". Montpellier 2, 1997. http://www.theses.fr/1997MON20224.
Texto completo da fonteLecrigny-Nolf, Sophie. "Maîtrise de l'hygiène des circuits fermés nettoyés en place en industrie laitière : Identification de voies d'amélioration". Compiègne, 2000. http://www.theses.fr/2000COMP1269.
Texto completo da fonteSampson, Gareth Milo. "Hydrogen atom and argon ion reactions for removing hydrocarbon adsorbates and contamination from silicon surfaces /". Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
Texto completo da fonteJacquin, Daniel. "Diagnostics et modélisation en volume d'un plasma multipolaire d'hydrogène utilisé pour le nettoyage de surfaces d'arseniure de gallium". Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37614452w.
Texto completo da fontePelleïeux, Sandra. "Intéraction de bactériophages avec des surfaces colonisées par des biofilms d'eau potable et évaluation de protocoles de nettoyage". Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0082/document.
Texto completo da fonteAlthough pathogens remain widely uncommon in water distribution networks, they may constitute a real threat for human health when accidentally introduced in the system. There is a lack of knowledge about virus behaviour into water distribution systems whereas such information is critical for a better viral risk management. In this context, three F-specific RNA bacteriophages -MS2, GA and Qbeta- were used as models, in experimental conditions mimicking water distribution systems. The purpose of the present work was at first to compare the viral accumulation of bacteriophages on high-density polyethylene (HDPE) colonised or not with drinking water biofilms. The second objective was to evaluate, on phages adsorbed in the biofilm, the efficiency of a cleaning protocol, based on chlorination and increase in the hydrodynamic strengths. To sum up, the water velocities tested in this work had little influence on both the bacterial and virus accumulation on surfaces, but applying a water flow led to an increase in the number of adsorbed phages in comparison with hydrostatic conditions. Whatever the conditions (water velocity, colonisation or not with a biofilm) MS2 phage was found to be the less adherent one. On HDPE colonised with a two-month old biofilm, the adhesion sequence was consistent with the sequence of hydrophobicity of the phages. The chlorination protocol tested in our study (4 to 5 mg CL2/L) can be applied punctually in distribution networks. After 60 minutes of chlorination the log-reduction was about 0.7 log10 for bacteria and between 2 and 3 log10 for bacteriophages, while no more infectious phages were detected in water after 5 minutes. Those results highlight that even two-month-old biofilms provide to viruses a protection against disinfection protocol. At last, the chlorination appears to be more efficient to inactivate viruses adsorbed on surfaces than an increase in the water flow velocity
Fauveau, Cédrine. "Validation de nettoyage appliquée à un produit liposoluble dans un atelier de fabrication de formes solides". Paris 5, 1998. http://www.theses.fr/1998PA05P186.
Texto completo da fontePigeon, Timothy David. "Studies of plume condensation contamination upon surfaces of the Terrestrial Planet Finder spacecraft". Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/34680.
Texto completo da fonteIncludes bibliographical references (leaves 81-82).
There are two competing concepts for the Terrestrial Planet Finder (TPF) mission, one which involves a single spacecraft, and another comprised of a five craft formation. In addition, there are several propulsion options under consideration. Unique contamination issues affect the formation-flying concept due to the close proximity of the spacecrafts. Select surfaces must be maintained at the low temperature of 40 K. There is concern that propellant expelled from one craft will condense on the cryogenic surfaces of a neighboring craft, adversely affecting performance and the integrity of the observational data. The condensation properties of warm Xenon, Krypton, and Argon upon a cryogenically-chilled QCM were characterized at a range of temperatures and pressures. Heats of adsorption were predicted with a model to solve for intermolecular forces, and experimental data was used to assess the model's validity. Knowledge of the heat of adsorption was used to determine the equilibrium level of surface coverage for both a pulsed and constant operation thruster, for a range of impinging gas fluxes. The model aims to aid in the selection of an appropriate propulsion system and propellant for the TPF spacecraft.
by Timothy David Pigeon.
S.M.
Vatanyoopaisarn, Savitri. "Formation of biofilms on stainless steel by Pseudomonas fluorescens and Listeria monocytogenes". Thesis, University of Nottingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310957.
Texto completo da fonteMoreau, Olivier. "Synthèse de greffons organiques à fonctionnalités antimicrobiennes. Greffage sur wafer de silicium. Aspects physico-chimiques de l'adhésion particulaire". Reims, 2006. http://theses.univ-reims.fr/sciences/2006REIMS034.pdf.
Texto completo da fontePreserving food safety implies, inter alia, to control the microbiological contamination of surfaces which are likely to be in contact with the foodstuffs. Various studies showed that this contamination by pathogenic germs resulted in fact from the adhesion of micro-organisms on the surfaces of materials, which is directly in contact with food. It is thus necessary to develop some strategies, ensuring that surfaces, which are in contact with food are not responsible for transmission of the pathogenic agents. With this intention, our approach is to modify the surface of the materials by grafting in order to either limit adhesion, or to develop antimicrobial activity. The design of these modified materials requires, initially, the synthesis of monomers, which have the possibility to graft and at the same time a fragment carrying the anti-bacterial activity. The covalent grafting of these monomers enable to increase the durability of the modified material and to limit the migration of the antimicrobial agent towards the foodstuffs
Pereira, Alexandre. "Processus physico-chimiques de contamination moléculaire phot-assistée sur satellites". École nationale supérieure de l'aéronautique et de l'espace (Toulouse ; 1972-2007), 2004. http://www.theses.fr/2004ESAE0010.
Texto completo da fonteAzar, Fadi. "Gels à révélateurs chimiques pour la détection de la contamination radioactive de surfaces solides". Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20063.
Texto completo da fonteThis work deals with the formulation of new gels to detect visually radioactive surface contamination α or γ by color changing. A thin gel film (<1mm) is sprayed onto the wall and is easily recovered after drying, Transparent, viscoelastic polymer xanthan gels and with radiosensitive dyes were selected.γ irradiation of organic dyes and colored complex Fe (II)- xylenol orange in silica and Xanthan gel were performed. Mechanisms and kinetics of oxidation by radiolysis were identified as a function of absorbed dose. The gel iron (II)-xylenol orange- Xanthane, noted FXX, revealed a spot of contamination by 137cesium (γ emitter of Activity0 = 20 KBq) after 48 hours by oxidation of the complex xylenol orange- ion (II). Moreover, the same gel detected a surface contamination by 239plutonium (transmitter Activity0 = 3720 Bq) after one day.For recovering after drying, the addition of silica to xanthan gel helped highlight a final dry residue delaminates at low concentration of silica or fracture at high silica concentration. However, the addition of acid (> 2 M) led to a partial drying of the gel giving a wet film recoverable
Obee, Peter. "Hospital surfaces and their importance in cross contamination and the spread and transmission of bacteria". Thesis, Cardiff Metropolitan University, 2009. http://hdl.handle.net/10369/844.
Texto completo da fonteGuay, Marianne. "Utilisation de la spectroscopie de fluorescence pour la vérification du nettoyage d'un ingrédient pharmaceutique actif sur les surfaces des équipements de production". Master's thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/28220.
Texto completo da fonteCleaning verification is used to assess the cleanliness of pharmaceutical process equipment. Cleanliness is established when the concentration of the residue of a pharmaceutical ingredient is lower than an acceptance limit. The method used to perform this verification consists of collecting a sample using a swab, and to analyze it using high performance liquid chromatography. The issue with this method is that it can take up to 2 days before the results are obtained, and before the equipment can be released for the production of another batch of drugs. Therefore, there is an opportunity to develop a new analytical method to quantify cleanliness in real-time without sampling (contactless). The new method investigated in this thesis uses fluorescence for direct quantification of ibuprofen residue. In this proof of concept, the impact of various parameters on the fluorescence signal was assessed. The best way to prepare the standards and how to analyze them with the instrument (the TraC) were determined. Following the verification of a first calibration curve using in situ data collection, the equipment was modified to allow the evaluation of equipment with an acceptance limit lower than the quantification limit of the TraC. The plant tests also revealed that the TraC always gives a higher concentration than the traditional method. An upgraded unit was calibrated, and the limit of quantification was lowered. It was established that the method is accurate (recovery is between 85 and 115%) and precise (relative standard deviation is lower than 5%), and that the excipients studied have no impact on the signal. Calibration curves were also built for aluminum, bronze, polyethylene and brass. Finally, the proof of concept for the use of the TraC for the cleaning verification of ibuprofen was demonstrated, and it is recommended to implement the method at a first plant.
Tran, Van Ba Thanh-Thuy. "Analyse des contaminations microbiennes des surfaces et mise au point de revêtements anti-biofilms". Lyon, INSA, 2000. http://www.theses.fr/2000ISAL0046.
Texto completo da fonteDevelopment of bio films on a bio tic surfaces raises a lot of problems in economic, sanitary and medicine fields. In order to fight this nuisance, there is a strong need to design non-toxic surface coating able to prevent, or at least to limit, the colonization process and the contamination of surfaces (marine materials, indwelling medical devices. . . ). In this purpose, we tried to develop surface treatments which « deceived » bacteria by modifying the microenvironment that they encounter at the interface between the material and the liquid medium. In a fist time, we designed a method of quantification of the colonization process based on epi-fluorescent microscopy. We utilized this technique to estimate the efficiency of surface coating obtained by cold plasma (at The Centre of Technological Transfer of Le Mans). Some surface coating delay colonization for several hours. This results lead to the deposit of a patent and allowed us to consider the treatment of urinary catheters with the aim to limit infections of the urinary tract following their implantation. A clinical study has therefore been initiated in collaboration with the Services of Urinary and Microbiology of the Edouard Herriot Hospital of Lyon. We received a lot of urinary catheters taken from infected patients and analyzed them by a method of visualization and identification of contaminating bacteria based on hybridization of oligo-nucleotide probes to ribosomal RNA (Fluorescent In Situ Hybridization\ We have also developed a method of imrnuno-detection of bacteria that have a particular structure of adherence to surfaces. These techniques give us the basis to begin the clinical study of urinary catheter treated by the coatings that we have designed
Chevallier, Isabelle. "Influence des interactions acido-basiques sur l'encrassement et la biocontamination de supports métalliques oxydés". Paris 11, 2002. http://www.theses.fr/2002PA112172.
Texto completo da fonteMetallic materials are of frequent use in food industry, where they are always in contact with macromolecular substances and a bacterial environment which can attach to metallic surfaces. To control this problem, a better understanding of the adhesion phenomenon is required. Adhesion of microorganisms to food processing equipment surfaces is the result of physicochemical interactions between cells and solid surfaces. If the role of Lewis acid-base interactions is often evoked, their real implication in the adhesion phenomenon has been not clearly demonstrated so far. To evaluate the role of Lewis acid-base interactions in serum albumin bovine (BSA) fouling and Listeria monocytogenes adhesion, we have prepared metallic surfaces with different acido-basic degrees: ferritic stainless steels, tantalum and cobalt. Physicochemical characterization of passive films has shown the significant contribution of the minor oxidisable elements in ferritic stainless steels, which can modify surface chemical composition and then lead to a variation of surface energy characteristics. The results obtained following BSA adsorption have shown that the protein adapts her molecular conformation to the substrate and underlined the role of Lewis acid-base interactions in surfaces fouling. The study of Listeria monocytogenes adhesion has revealed the importance of the adsorbed layer to reduce the microbial contamination. Thus the control of surface acid-base properties should allow to obtain a controlled adsorbed layer which is a natural conditioning film of surfaces and can either inhibit the microbial adhesion or, reversely, increase this phenomenon
Martin, Cabañas Bruna. "Comportement des produits de corrosion dans le circuit primaire des centrales REP : sorption du cobalt et du nickel sur des ferrites représentatifs". Paris 11, 2010. http://www.theses.fr/2010PA112245.
Texto completo da fonteThe corrosion of the metal parts in the primary circuit of PWR Ieads to the release of metal oxides particles and ionic species. These corrosion products circulate through the primary circuit and may be activated when they pass through the core. The deposition of the activated particles in areas out of flux is then responsible for surface contamination. These particles can also interact with thc ionic species in the primary medium, contributing to their transport and to their deposition on surfaces outside the flux. Ln order to have better contamination control, characterization (specific surface, sire, PZC. . . ) of differents particles of primary circuit and study of their interaction with soluble species and surfaces (adhesion, sorption. . . ) is necessary. Species take into account in this study are for particles : nickel and cobalt ferrites and magnetite, for primary circuit materials: Inconel 690, Zircaloy 4 and stainless steel 304L. Cobalt and nickel sorption, main responsible of primary circuit contamination, on several corrosion products were experimentally realized and modelised with ECOSAT code. Surface charge were also studied. Data obtained will be introduced in different calculation code in order to modelised contamination in primary circuit under dynamics conditions
Fatima, Nowshir. "Wet clutch friction reliability : influence of water contamination and system design". Licentiate thesis, Luleå tekniska universitet, Maskinelement, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26351.
Texto completo da fonteGodkänd; 2012; 20120813 (nowfat); LICENTIATSEMINARIUM Examinator: Professor Roland Larsson, Institutionen för teknikvetenskap och matematik, Luleå tekniska universitet Diskutant: Donald McCarthy, Volvo Tid: Fredag den 14 september 2012 kl 10.00 Plats: D770, Luleå tekniska universitet
Dittes, Nicholas J. "Condition Monitoring of Water Contamination in Lubricating Grease for Tribological Contacts". Licentiate thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-25635.
Texto completo da fonteMeylheuc, Thierry. "Influence de biosurfactants sur l'adhesion de listeria monocytogenes a des surfaces inertes : consequences sur la desinfection (doctorat : microbiologie)". Paris 11, 2000. http://www.theses.fr/2000PA114835.
Texto completo da fonteParis, Jean-Baptiste. "Développement de surfaces plastiques aux propriétés antibactériennes par immobilisation covalente de produits naturels". Rouen, 2016. http://www.theses.fr/2016ROUES001.
Texto completo da fonteIn the field of cosmetics, legislation on the use of preservatives in formulations, for ensuring microbiological integrity of the products, becomes more and more restrictive (as the recent example of parabens). To overcome these changes, a possible solution is the development of active packaging. The work described herein consisted of developing high density polyethylene (PE) surfaces by covalent immobilization of natural compounds to introduce antibacterial properties to those surfaces. Thus, antifouling surfaces, based on hyaluronic acid (HA) immobilization, and bactericidal or bacteriostatic surfaces, based on antimicrobial peptides (AMPs), have been developed. Various parameters such as the activation rate, molecular weight of HA or orientation of AMPs have been studied by various techniques such as contact angle measurements and XPS analysis. Finally the two approaches have been combined by various strategies to immobilize together the two families of compounds. The developed surfaces based on AMPs showed activity against S. Epidermidis and P. Aeruginosa, depending especially of the peptide used and its concentration. HA-based surfaces have led to a reduction of bacterial adhesion by more than 1 log (90%). Combination of biocidal and antiadhesive properties, although based on opposed physicochemical phenomena, produces surfaces with antibacterial activity that exceeds 2-Log reduction (99%) against S. Epidermidis
Al, Saabi Alexandre-Ahmad. "Mousses en écoulement pour le nettoyage d’équipements fermés contaminés par des spores de Bacillus cereus ou des biofilms de Pseudomonas fluorescens". Thesis, Lille 1, 2020. http://www.theses.fr/2020LIL1R015.
Texto completo da fonteContaminants such as spores/biofilms are problematic in many food industry sectors. Indeed even after hygiene procedures, biofilms/spores could be found on every surface that is in direct contact or not with food (Bénézech & Faille, 2018). Risks associated with microorganisms can be controlled either by limiting the number of adherent cells or by facilitating the removal of adherent bacteria. Even though Cleaning in Place (CIP) is widely used and it is a common cleaning practice in food industries; however, it remains at some level a high- water consumption procedure. In addition, some studies, presented some bacterial species that still survived even after CIP and maybe a probable source of product contamination. On the other hand, a double phase fluid such as foam can impose the same wall shear stress with less water being consumed. Foam with its properties such as shearing can be key a parameter for a mechanical cleaning of closed systems such as pipes with a lower consumption of water.In this study we investigated the effect of flowing foam in pipes and compared its efficiency with standard CIP like conditions on the detachment of spores and biofilms. The first approach was working with different foam flow regimes (1D, 2D, 3D while increasing the velocity from 2 to 6 cm s-1) having different foam qualities (amount of air: 50%, 60%, 70%) on different species of microorganisms where fouling was performed either by using spores of B. amyloliquefaciens 98/7 or B. cereus 98/4 that shows a difference by their hydrophobic/hydrophilic character. As for P. fluorescens pf1 it was used as a good biofilm former (24 hrs. biofilm) widely encountered in the food industry. Fouling was performed either vertically or horizontally inducing biofilms with different structures. Results from foam cleaning were compared with CIP like conditions results (the same mean mechanical action, and the same concentration of surfactant). The second approach was subjecting foam flow to different singularities (sudden expansion gradual reduction – bends) while working with one foam flow regime (1D 50%) and one species (B. amyloliquefaciens 98/7 spores) to highlight any changes in the foam flow cleaning efficiency. The third approach was working also with one species (B. amyloliquefaciens 98/7) considered as a good “microbial tool” producing foam from the use of different surfactants (SDS, Capstone® FS 30, Ammonyx® LO) that differs by their chemical properties ( nonionic, anionic and zwitterion) thus producing different foams having different physical properties in terms of bubbles size , number and repartition, and flow pattern. Comparing to previous related works on foam flow characterization, it was possible to highlight the potential role on the cleaning efficiency of the Wall Shear Stress variations in parallel to the liquid film thickness variation at the wall with the bubbles' passage. In addition, according to previous work, the possible capillary forces exerted under the lowest flow rates and considering the hydrophilic/hydrophobic nature of the spores, in addition to biofilm structure would explain at least partly the surprising efficiency in the spores' removal by foam
Al, Saabi Alexandre-Ahmad. "Mousses en écoulement pour le nettoyage d’équipements fermés contaminés par des spores de Bacillus cereus ou des biofilms de Pseudomonas fluorescens". Electronic Thesis or Diss., Université de Lille (2018-2021), 2020. http://www.theses.fr/2020LILUR015.
Texto completo da fonteContaminants such as spores/biofilms are problematic in many food industry sectors. Indeed even after hygiene procedures, biofilms/spores could be found on every surface that is in direct contact or not with food (Bénézech & Faille, 2018). Risks associated with microorganisms can be controlled either by limiting the number of adherent cells or by facilitating the removal of adherent bacteria. Even though Cleaning in Place (CIP) is widely used and it is a common cleaning practice in food industries; however, it remains at some level a high- water consumption procedure. In addition, some studies, presented some bacterial species that still survived even after CIP and maybe a probable source of product contamination. On the other hand, a double phase fluid such as foam can impose the same wall shear stress with less water being consumed. Foam with its properties such as shearing can be key a parameter for a mechanical cleaning of closed systems such as pipes with a lower consumption of water.In this study we investigated the effect of flowing foam in pipes and compared its efficiency with standard CIP like conditions on the detachment of spores and biofilms. The first approach was working with different foam flow regimes (1D, 2D, 3D while increasing the velocity from 2 to 6 cm s-1) having different foam qualities (amount of air: 50%, 60%, 70%) on different species of microorganisms where fouling was performed either by using spores of B. amyloliquefaciens 98/7 or B. cereus 98/4 that shows a difference by their hydrophobic/hydrophilic character. As for P. fluorescens pf1 it was used as a good biofilm former (24 hrs. biofilm) widely encountered in the food industry. Fouling was performed either vertically or horizontally inducing biofilms with different structures. Results from foam cleaning were compared with CIP like conditions results (the same mean mechanical action, and the same concentration of surfactant). The second approach was subjecting foam flow to different singularities (sudden expansion gradual reduction – bends) while working with one foam flow regime (1D 50%) and one species (B. amyloliquefaciens 98/7 spores) to highlight any changes in the foam flow cleaning efficiency. The third approach was working also with one species (B. amyloliquefaciens 98/7) considered as a good “microbial tool” producing foam from the use of different surfactants (SDS, Capstone® FS 30, Ammonyx® LO) that differs by their chemical properties ( nonionic, anionic and zwitterion) thus producing different foams having different physical properties in terms of bubbles size , number and repartition, and flow pattern. Comparing to previous related works on foam flow characterization, it was possible to highlight the potential role on the cleaning efficiency of the Wall Shear Stress variations in parallel to the liquid film thickness variation at the wall with the bubbles' passage. In addition, according to previous work, the possible capillary forces exerted under the lowest flow rates and considering the hydrophilic/hydrophobic nature of the spores, in addition to biofilm structure would explain at least partly the surprising efficiency in the spores' removal by foam
Buchholz, Florian. "Metal surface contamination in c-Si solar cell processing". Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2016. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-203660.
Texto completo da fonte