Dissertations / Theses: 'In situ injection'

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Gujar, Surabhi Satyajit. "Detecting Electromagnetic Injection Attack on FPGAs Using In Situ Timing Sensors." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/97006.

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Nowadays, security is one of the foremost concerns as the confidence in a system is mostly dependent on its ability to protect itself against any attack. The area of Electromagnetic Fault Injection (EMFI) wherein attackers can use electromagnetic (EM) pulses to induce faults has started garnering increasing attention. It became crucial to understand EM attacks and find the best countermeasures. In this race to find countermeasures, different researchers proposed their ideas regarding the generation of EM attacks and their detection. However, it is difficult to see a universal agreement on the nature of these attacks. In this work, we take a closer look at the analysis of the primary EMFI fault models suggested earlier. Initial studies had shown that EM glitches caused timing violations, but recently it was proposed that EM attacks can create bit sets and bit resets. We performed a detailed experimental evaluation of the existing detection schemes on two different FPGA platforms. We present their comparative design analysis concerning their accuracy, precision, and cost. We propose an in situ timing sensor to overcome the disadvantages of the previously proposed detection approaches. This sensor can successfully detect most of the electromagnetic injected faults with high precision. We observed that the EM attack behaves like a localized timing attack in FPGAs which can be identified using the in situ timing sensors.
MS

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Walter, David J. "Soil enhancement by fluid injection for in situ treatment of contaminated soil." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0008/NQ52695.pdf.

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Chuah, Siew Peng. "In-situ fibre formation & management of thermotropic liquid crystalline polymers in thermoplastic matrices." Thesis, Brunel University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295188.

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Mohammad, Ahmad A. A. "Experimental investigation of in situ upgrading of heavy oil by using a hydrogen donor and catalyst during steam injection." Texas A&M University, 2008. http://hdl.handle.net/1969.1/86051.

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Experiments were conducted to investigate the feasibility of in situ upgrading of heavy oil by the use of an orgametallic catalyst and a hydrogen donor (tetralin). The experiments used a vertical injection cell into which a mixture of sand, water, and Jobo oil was thoroughly mixed and packed. Two types of runs were conducted: a run where the tetralin and catalyst were mixed within the mixture before packing into the cell, and the other was conducted by injecting a slug of the tetralin-catalyst solution before commencing with the steam injection. The Jobo oil used had an oil gravity of 12.4° API and a viscosity of 7800 cp at 30°C. The injection cell was placed in a vacuum jacket and set to a reservoir temperature of 50°C. Superheated steam at 273°C was then injected into the injection cell at a rate of 5.5 cc/min (cold water equivalent). The cell outlet pressure was maintained at 500 psig. Produced liquid samples were collected periodically through a series of separators. The produced oil was divided into two halves and several measurements and analyses were carried out on them. These included viscosity, density, elemental analysis and liquid composition. Experimental results indicated that tetralin alone was a worthy additive and increased recovery by 15% compared to that of pure steam. The premixed tetralincatalyst run showed improved recovery to that of pure steam by 20%. Experiments also showed that, when the tetralin-catalyst solution was injected rather than mixed, the results were equivalent to tetralin injection runs. Oil production acceleration was displayed by all the runs with tetralin and tetralin-catalyst but was more pronounced with the availability of catalyst.

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Palmén, Anders. "Stabilization of frictional soil through injection using CIPS (Calcite In-situ Precipitation System)." Thesis, KTH, Jord- och bergmekanik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-109361.

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The precipitation system CIPS (Calcite In-situ Precipitation System) has been created as a permeation grouting system based on a two component fluid with the intention of slowly permeate and fill the pores. It causes cementation through a chemical reaction which bonds the soil particles together at the contact points. CIPS mimics one of the natural reactions in nature where sandstone is formed through calcite precipitation. This system is used in Australia with excellent results and there are many factors governing the outcome of the method, some of these factors are: flow rate, pressure, time, chemical recipe, temperature, composition of the soil matrix and number of performed injections at the same point of location. Some of these factors have been the focus of this report and where they have been examined from a Scandinavian point of view where our ground temperature conditions and soil compositions have governed the outcome of the accomplished results. The strength increase has been examined through laboratory tests where natural sand from a building site with known particle size and dry density has been treated once with the CIPS Fluid. This treatment was completed in a temperature controlled room of 12 degrees after which the treated soil was tested by unconfined compression tests. Even a rather low increase in bearing capacity of the soil would result in benefits during the construction of temporary constructions during the early building stages foundation work. Since the desired increase in bearing capacity of the soil is fairly low, 50-100 kPa, the investigations has concentrated on one single injection, in order to study if there is a clear trend in the increase in bearing capacity, and if it can be roughly predicted. In addition to the above mentioned laboratory work a small scale field test has been conducted, where the CIPS Fluid was injected into the ground with the aim of creating a column shaped object. This column was left for a certain time, a time long enough for the calcite crystal to bond the soil grains and generate an increase in strength. When the assumed cementation had occurred an ocular assessment was carried out in order to predict whether the strength had increased or not, and to what degree. Based on the laboratory results, some evidence of that strength increase occurs due to either the discharge of the spent fluid containing ammonium chloride or the process of drying. Either way, the strength increase takes place during the grounds natural process of adjusting towards the natural water content equilibrium for the specific site of interest. A strength increase at the laboratory experiments of between approximately 60-220 kPa has been achieved. The field tests where slightly less rewarding when difficulties of injecting the CIPS Fluid into the sandy soil arose due to challenging task of designing a pumping system where both a low pressure, less than the overburden pressure, and a low flow rate, less than 7 litres per minute, could be controlled. The flow rate could be controlled but with the effect of the pressure rising to too high levels. Due to the observations of CIPS Fluids exiting the ground at other points than near the injection spear, soil fractures are assumed to have occurred at one ore many locations. The volumes treated with CIPS Fluid displayed no increase in strength as long as they appeared somewhat wet with the spent fluid. When this fluid containing ammonium chloride vanished from the treated soil and the pH-value dropped, the build up in strength through calcite crystallisation at the contact points began. This crystallization which leads to a cementation was observed at the centre of the small spheres achieved through injection in the ground, which proves that the Calcite In-situ Precipitation System has caused a cementation of the soil grains treated.

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David, Anthony R. J. "Flow injection instrumentation for the in situ monitoring of nutrients in sea water." Thesis, University of Plymouth, 1996. http://hdl.handle.net/10026.1/1690.

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In order to investigate the biogeochemistry of aquatic ecosystems, a quantitative understanding of primary production and the temporal and spatial distribution of nutrients is necessary. This thesis describes the development of a submersible FI based nutrient sensor for the in situ determination of nitrate in estuarine and coastal waters. Chapter One describes the role of nitrogen in the global and marine nitrogen cycles and provides an overview of laboratory and in situ methods for its determination. Chapter Two describes the key parameters for a field instrument and culminates with the overall design specification for the system. Chapter Three describes in detail the design, build and optimisation of the key individual components of the system, e.g. sample delivery system, injection valve, reduction column, reaction column, flowcell, on-board control system and the housing of the complete integrated system. Chapter Four describes the optimisation and analytical performance of the FI instalment prior to field trials. The key operational parameters such as flowcell path length, injection volume and detector response were investigated. LOD, reproducibility and linear range were determined and the control programme for the onboard computer is reported. For example, a LOD of 0.01 Nitrate-N, a linear range of 0-140 | iM Nitrate-N and a reproducibility of ± 5 % were achieved. Chapter Five describes the field experiments where the FI system was initially used as a bench instrument and compared to a laboratory FI method which had been validated by participation in two interlaboratory exercises and for nitrate in river and sea water. The first submersed deployments involved the optimisation of the system operational characteristics and developing the field techniques. The final part of this chapter describes the weekly field studies of Barn Pool in Plymouth Sound using the submersed nutrient sensor for a period of two months. The operation and performance of the submersed sensor was assessed against an air segmented continuous flow analyser during a Land Ocean Interaction Study (LOIS) North Sea cruise aboard the RVS Challenger. The results from this exercise and the relevant salinity and turbidity measurements are presented in Chapter Six.

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McCormack, Trevor. "Flow injection chemistries for the in situ monitoring of nutrients in sea water." Thesis, University of Plymouth, 1996. http://hdl.handle.net/10026.1/494.

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Pitterle, Mark Thomas. "Push-pull Tests to Quantify In-situ Naphthalene Phytoremediation Rates." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/41282.

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Ten strategically placed push-pull wells were installed to determine in-situ degradation rates at a creosote contaminated site and to assess the contribution of hybrid poplar trees to polynuclear aromatic hydrocarbon (PAH) remediation. Well positioning enabled comparison between contaminated and non-contaminated locations, as well as comparisons between locations with and without trees. Comparison of areas with and without trees enabled an improved understanding of the role that the phytoremediation system has on the overall degradation of PAHs at the site. Bromide, a conservative, non-reactive tracer, was injected in solution along with dissolved oxygen. Twelve push-pull tests (PPTs) were performed, of which three did not include naphthalene in the injection solution, so that the developed method could be evaluated, tested, and yield an initial set of rates to make seasonal and spatial varying in-situ comparisons. Method comparison used for rate analysis found the highest confidence in the method of Snodgrass and Kitanidis (1998) for zero order rates and the method of Haggerty et al. (1998) for first order rates. The largest zero and first order rates, 2.43 mgnaphthalene/L-hr and 1.25 1/hr, respectively, occurred at treed regions in June. Zero and first order winter rates at treed regions were greater by a factor of at least 2.5 when compared to non-treed regions. Degradation rates at treed regions were found to steadily increase by over four times from winter to summer. Results validate that decay variations attributed to phytoremediation can be detected with the push-pull method. PPTs performed at the Oneida site verified observed trends determined from six years of monitoring data, microbial characterization, and microcosm studies.
Master of Science

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Tingas, John. "Numerical simulation of air injection processes in high pressure light & medium oil reservoirs." Thesis, University of Bath, 2000. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343763.

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Research, pilot scale and field developments of In-Situ Combustion (ISC) for enhanced oil recovery (EOR) in shallow, low pressure, heavy oil reservoirs intensified between the first and the second oil crisis from 1973 to 1981. A decline of interest in EOR followed the collapse of the oil prices in 1986. Renewed interest on in-situ combustion EOR research in the late 1980’s and beginning of the 1990’s was expanded and focused on high pressure medium and light oil reservoirs. The applicability of air injection in deep high pressure light petroleum reservoirs was established by research work of Greaves et al. in 1987 & 1988, Yannimaras et al. in 1991 and Ramey et a l in 1992. Accelerating rate calorimeter (ARC) tests were used to screen the applicability of various types of light oil reservoirs for in-situ combustion EOR by Yannimaras and Tiffin in 1994. The most successful light oil air injection project in the 1990s in the Medicine Pole Hills Unit, Williston Basin, N. Dakota started in 1987 and was reported by Kumar, Fassihi & Yannimaras, in 1994. Low temperature oxidation of light North Sea petroleum was studied at the University of Bath. A high-pressure combustion tube laboratory system was built at Bath University to evaluate performance of medium and light petroleum in-situ combustion processes. Gravity effects and the impact of horizontal wells in Forced Flow In-Situ Combustion Drainage Assisted by Gravity (FFISCDAG) were studied with three-dimensional combustion experiments. In this study, the university of Bath combustion tube experiments have been simulated and history matched. The tube experiments were up-scaled and field simulation studies were performed. A generic PVT characterization scheme based on 5 hydrocarbon pseudo-components was used, which was validated for light Australian and medium ‘Clair’ oil. A generic chemical reaction characterization scheme was used, which was validated for light Australian and medium ‘Clair’ oil. Advanced PVT and chemical reaction characterizations have been recommended for future work with more powerful hardware platforms. Extensive front track and flame extinction studies were performed to evaluate the performance of currently available non-iso-thermal simulators and to appraise their necessity in air injection processes. Comparative ISC field scale numerical simulation studies of Clair medium oil and light Australian petroleum were based on up-scaled combustion tube experimental results. These studies showed higher than expected hydrocarbon recovery in alternative EOR processes for both pre and post water flood implementation of ISC. Further in this study field scale numerical simulation studies revealed high incremental hydrocarbon recovery was possible by gravity assisted forced flow. The applicability of light oil ISC to gas condensate and sour petroleum reservoirs has been examined in this study with promising results. Light petroleum ISC implemented by a modified water flood including oxidants such as H2O2 and NH4NO3 are expected to widen the applicability of ISC processes in medium and light petroleum reservoirs, especially water flooded North Sea reservoirs.

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O'Donnell, Hugh J. "In situ composites of compatibilized polypropylene/liquid crystalline polymer blends." Diss., This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-02052007-081243/.

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Benali, Samira Maazouz Abderrahim Dupuy Jérôme. "Etude cinétique et rhéologique de systèmes polyuréthanes application au suivi in-situ du procédé RIM /." Villeurbanne : Doc'INSA, 2005. http://docinsa.insa-lyon.fr/these/pont.php?id=benali.

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Al-Honi, Mohamed Al-Arbi. "Three-dimensional physical model studies of air injection- in-situ combustion process : effect of reservoir heterogeneity." Thesis, University of Bath, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242786.

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Bordenave, Alexandre. "Traitement in situ des HAPs par co-injection air-vapeur : mécanismes physico-chimiques et optimisation énergétique." Thesis, Bordeaux 3, 2015. http://www.theses.fr/2015BOR30021/document.

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La contamination du milieu naturel, notamment des aquifères, par des hydrocarbures lourds de type HAP (Hydrocarbure Aromatique Polycyclique) se révèle être une pollution pérenne très difficile à traiter. La dépollution de ces sous-sols par un traitement in situ efficace et peu coûteux constitue encore aujourd’hui un challenge. Cette étude cible une technique de co-injection air-vapeur en zone saturée comme alternative aux techniques thermiques et chimiques en vigueur pour le traitement de cette catégorie d’hydrocarbures. Une première partie expérimentale introductive estime l’influence d’un simple traitement vapeur sur la libération de HAPs par les matrices de sol au sein de l’aquifère, montrant la nécessité de coupler à ce procédé une technique d’oxydation chimique. Si le front de vapeur permet de mobiliser totalement les composés légers, les concentrations des composés les plus lourds augmentent en phase dissoute (augmentation des fractions molaires des composés résiduels). Réalisées en milieu fermé, dans des conditions de température dictées par l’injection de vapeur (120 ̊C), des expériences en laboratoire ont permis de caractériser et de quantifier les réactions d’oxydation chimique mises en jeu. Les résultats démontrent une efficacité modérée de l’oxydation à moyenne température. Des sous-produits de réaction sont identifiables et quantifiables à compter de plusieurs semaines de réaction. A l’inverse l’étude met en évidence l’absence totale de minéralisation, démontrant que l’ana- lyse du CO2 ne peut renseigner sur l’évaluation du phénomène d’oxydation. Hormis la réactivité par oxydation, les conclusions de l’étude montrent que la technique favorise la sorption irréversible des composés organiques en surface des matrices de sol. Ces phénomènes de sorption sont très marqués en présence d’argile ou de matière organique naturelle dans le milieu et augmentent au cours du temps. La technique HPO se pose donc en traitement de soutien à l’injection de vapeur par oxydation mais surtout par stabilisation de la zone de contamination. Enfin nous nous sommes intéressés aux problématiques liées à l’injection d’eau chaude et de vapeur dans un sous-sol au travers d’expériences sur site. La technique d’injection de vapeur étant financièrement et énergétiquement coûteuse, des solutions techniques ont été proposées, appliquées et modélisées. Il en ressort une comparaison en bilans énergétiques pour différents modes d’injection, permettant de mieux appréhender les véritables besoins d’une telle technique. Parmi les paramètres influents, le rayon d’influence est un paramètre essentiel qui conditionne la distance entre chaque puits pour une efficacité optimale. Les résultats de l’étude démontrent que dans certains scénarios d’injection (injection à grande profondeur) le préchauffage de la zone d’étude par injection d’eau chaude couplé à un pompage en profondeur permettra d’accroître significativement le rayon d’influence et d’améliorer le bilan énergétique du traitement global. Les principaux résultats de la thèse sont comparés aux autres études sur l’injection de vapeur pour dégager les meilleures conditions d’application de cette technique, et mettre en évidence les verrous techniques ayant pu être levés au cours de la thèse
PAHs are the largest, ubiquitous and carcinogenic environmental chemical groups. In a context of polluted soil remediation, today it is still a challenge to reach an effective in situ treatment. This study aims to evaluate as an alternative way the potential of a technology combining a thermal process (injection of steam) and a chemical process (co-injection of air) in the saturated zone. A first introductory experimental section considers the influence of a single steam treatment on the release of PAHs from soil matrices within the aquifer. Results prove the necessity of coupling a chemical oxidation technique with this process. If the steam front allows to recover light com- pounds, concentrations of heavier compounds in the dissolved phase are more important after the steam treatment (molar fractions of residual compounds increase). In order to study the fate of PAHs in polluted soils under medium temperature oxidation, numerous experiments in presence of soil spiked matrices were carried out in closed reactors. The catalytic potential of different mineral surfaces was investigated by studying reactivity of different PAHs. Results demonstrate that the efficiency of oxidation remains moderate. They suggest a lack of mineralization and reactions producing partly polycyclic aromatic compounds (PACs) with equivalent molecular weight as the initial contaminants. Along short term experiments (9 days), the major effect of heating is an increase in irreversible sorption of original compounds. Interestingly, this sorption mostly occurs in presence of natural organic matter and oxygen in the gas phase, suggesting a specific reactivity of the natural organic matter. In long term experiments (6 months), new oxygenated PACs were formed and remained fixed on the solid phase. Consequently, air oxidation catalyzed by minerals and natural organic matter may be a new pathway concerning PAH stabilization in soils. The steam injection technique is still considered as a costly technique. In this last part some technical solutions have been proposed, implemented and modelized. The economic aspect of some injection cases are compared, based on the results of a real field application and some general calculations regarding the costs of wells and energy. Among influential parameters, the radius of influence is a key parameter that determines the distance between each well for an optimum efficiency. The results of this study show that in some scenarios of injection (when the injection takes place in a deeper zone), a preheating phase can be an interesting option to reduce the financial costs of the technique. The main results of the thesis are compared with other steam injection studies to identify the best conditions for the technique application

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Greene, John A. "An Investigation of Engineered Injection and Extraction as an in situ Remediation Technique for Uranium-Contaminated Groundwater." Thesis, University of Colorado at Boulder, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10682286.

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During in situ remediation of contaminated groundwater, a treatment chemical is injected into the contaminated groundwater to degrade a contaminant through chemical reaction that occurs in the subsurface. Reactions and subsequent contaminant degradation occur only where the treatment chemical contacts the contaminant long enough to complete degradation reactions. Traditional in situ groundwater remediation relies on background groundwater flow to spread an injected treatment chemical into a plume of contaminated groundwater.

Engineered Injection and Extraction (EIE), in which time-varying induced flow fields are used to actively spread the treatment chemical into the contaminant plume, has been developed to increase contact between the contaminant and treatment chemical, thereby enhancing contaminant degradation. EIE has been investigated for contaminants degrading through irreversible, bimolecular reaction with a treatment chemical, but has not been investigated for a contaminant governed by complex biogeochemical processes. Uranium fate and transport in subsurface environments is governed by adsorption, oxidation reduction, solution, and solid-phase interactions with naturally occurring solution species, microbial communities, minerals and aquifer media. Uranium primarily occurs in aqueous, mobile U(VI) complexes in the environment but can be reduced to sparingly soluble, immobile U(IV) solid-phase complexes by native dissimilatory metal reducing bacteria.

This work investigates the ability of EIE to promote subsurface delivery of an acetate-amended treatment solution throughout a plume of uranium-contaminated groundwater to promote in situ growth of native microbial communities to immobilize uranium. Simulations in this investigation are conducted using a semi-synthetic flow and reactive transport model based on physical and biogeochemical conditions from two uranium contaminated sites: the Naturita Uranium Mill Tailings Remedial Action (UMTRA) Project site in southwestern Colorado and the Old Rifle UMTRA Project site in western Colorado.

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Beckmann, Annika. "Direct oxygen injection experiments and investigation of multi-component mass transfer processes." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola&quot, 2009. http://nbn-resolving.de/urn:nbn:de:swb:105-223858.

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The aim of this thesis was to investigate the impact of a direct oxygen injection as a potential remediation strategy for contaminated aquifers on a bench scale. The mass transfer between a multi-component trapped gas phase and a mobile water phase was studied. Column experiments with dynamically compressed sediments and a direct gas injection of pure oxygen gas were performed. In addition, a new developed kinetic multi-component model was used to describe the experiments. The amount of gas that could be captured in the pore space during direct oxygen injection and the time needed for a complete dissolution of the trapped gas phase were determined. Varying influences of different gases already dissolved in the mobile water phase on the dissolution process of a trapped oxygen gas phase were described for different flow regimes and confirmed by the model results. Finally, on the basis of the experimental and model results obtained in this thesis, predictions for an application of a direct oxygen injection in the field were discussed.

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LUNA, MICHELA. "Injection of zerovalent iron particles: from laboratory scale to field application." Doctoral thesis, Politecnico di Torino, 2013. http://hdl.handle.net/11583/2507554.

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L’attività di ricerca, e di conseguenza della tesi di dottorato, si inserisce all’interno di un Progetto Europeo riguardante la Gestione dei bacini idrografici contaminate (AQUAREHAB). In particolare, la tesi riguarda l’iniezione in siti contaminati da solventi clorurati di particelle di ferro zerovalente nano e micro-metriche disperse in sospensioni acquose. Le sospensioni ferrose sono sospensioni colloidali fortemente instabili, in cui le particelle tendono ad aggregare e successivamente sedimentare. Dal punto di vista operativo in campo questo comporta scarsa mobilità delle particelle nel mezzo poroso (basso raggio di influenza) e possibilità che le particelle sedimentino nel mezzo di iniezione. Sono stati condotti test di laboratorio per valutare l’efficacia di alcuni polimeri biodegradabili nella stabilizzazione delle sospensioni; inoltre queste sospensioni sono state caratterizzate dal punto di vista reologico e sono stati condotti test di trasporto per valutarne la mobilità nel mezzo poroso. Successivamente è stata condotta una ricerca sulle tecnologie di iniezione per permeazione e fatturazione. Le prime garantiscono una distribuzione uniforme di particelle nel mezzo poroso ma richiedono elevato grado di stabilizzazione e non assicurano elevati raggi di influenza. Contrariamente, la fatturazione risulta più semplice da realizzare, ma generando percorsi preferenziali, rende impossibile prevedere o modellizzare la distribuzione delle particelle nel sottosuolo. Sulla base dei risultati emersi dalle prove di laboratorio e dalla ricerca sulle tecniche di iniezione, è stato progettato un test pilota, eseguito a Aarschot (Belgio) a novembre 2011, il cui monitoraggio è durato sino a giugno 2012.

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Nickson, Robert Anthony. "In-situ preconcentration of trace metals in natural waters and brines with analysis by flow injection atomic spectrometry." Thesis, University of Plymouth, 1998. http://hdl.handle.net/10026.1/2091.

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Atomic spectrometric techniques such as ICP-MS offer exceptional sensitivity and multi-element capability for trace metal analysis but the formation of polyatomic ions (particularly below m/z = 80) can cause serious interferences. Such interfering species may be introduced via precursor atoms in atmospheric gases, the sample matrix or impurities in the reagents and gases. There is an environmental need to establish rapid multi-element methods of analysis for trace metals in environmental waters and the subsequent speciation of these trace elements. Natural waters, particularly those with a high dissolved solids content such as sea water are difficult to analyse directly by ICP techniques due to the sample matrix forming polyatomic ion interferences when using ICP-MS and matrix modification of the background when undertaking ICP-AES studies. This thesis describes the development of analytical methodologies involving on-line sample preconcentration and matrix removal for the determination of trace elements in natural waters and brines using ICP-MS and ICPAES detection for the determination of a suite of trace elements including cadmium, cobalt, copper, lead manganese, nickel, selenium and zinc. Chapter one summarises the techniques used for such analyses and a review of solid phases used for sample preconcentration and matrix removal is given. Chapter two describes the development of an on-line Fl-atomic spectrometric matrix elimination method for the determination of trace metals in the samples discussed. The method involved the chelation of the analytes onto a Metpac CC-1® IDA resin with the simultaneous removal of matrix ions, e.g. Na and CI. The method was successfully validated for the analysis of open ocean sea water and riverine water, and the application of FI-FAAS to the determination of Mn in riverwater using extended preconcentration times to improve sensitivity is described. The influence of sample matrix on the atomic emission of these trace analytes is also discussed. Chapter three describes the application of the developed method to the quantification of trace elements in produced water samples from the north sea oil and gas production fields. Results using FI-ICP-MS and FI-ICP-AES are compared, and a sample is digested using U.V. radiation in order to determine the amount of trace analytes bound to organic material. The influence of matrix concentration on analyte retention and column capacity is investigated, and data obtained from a series of breakthrough curves is used to predict the maximum breakthrough volumes of sample required before analyte is lost as the operating capacity of the column is exceeded, for samples of differing salinities. Chapter four describes the development of an in-situ method of preconcentration of a suite of trace elements using the column system described previously. In-situ preconcentration offers a number of advantages over traditional sample collection and preservation techniques and minimises the potential for sample contamination. The in-situ method involves the use of a battery powered preconcentration unit containing columns, reagents and suitable reagent and sample pumping facilities, and subsequent analysis of these samples in the laboratory by the use of FI-ICP-AES. The method is successfully validated using a coastal sea water certified reference material, and the method is applied to the determination of trace elements in a sample taken from the Tamar Estuary, Devon. Chapter five describes the development of an on-line FI preconcentration-HG-ICP-AES method for the speciation of inorganic selenium in water. Sample was preconcentrated on a Benson BA-XIO® exchange resin. On-line separation of Se(IV) and Se(VI) was achieved, and sensitivity was improved by the adoption of hydride generation prior to analysis for the determination of Se(IV). Se(VI) was determined after off-line pre-reduction to Se(IV). The method was tested by the determination of inorganic selenium in an SRM, NIST 1643C, Trace elements in water and results compared with previous work.

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Al-Saghr, Abdulbaset Mohammed. "Three-dimensional physical model studies of air injection : in-situ combustion and downhole catalytic upgrading using horizontal wells." Thesis, University of Bath, 1998. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760710.

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Beckmann, Annika. "Direct oxygen injection experiments and investigation of multi-component mass transfer processes." Doctoral thesis, [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=980851246.

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Rodriguez, Jose Ramon. "Experimental and analytical study to model temperature profiles and stoichiometry in oxygen-enriched in-situ combustion." Texas A&M University, 2003. http://hdl.handle.net/1969.1/134.

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A new combustion zone analytical model has been developed in which the combustion front temperature may be calculated. The model describes in the combustion zone, the amount of fuel burned based on reaction kinetics, the fuel concentration and produced gas composition based on combustion stoichiometry, and the amount of heat generated based on a heat balance. Six runs were performed in a 3-inch diameter, 40-inch long steel combustion tube with Jobo crude oil (9-11°API) from the Orinoco Belt in Venezuela. These runs were carried out with air containing three values of oxygen concentration, 21%, 30%, and 40%. The weight percentage of sand, clay, water, and oil in the sand mix was kept constant in all runs at 86.6%, 4.7%, 4.0%, and 4.7% respectively. Injection air rates (3 L/min) as well as the production pressure (300 psig) were kept constant in all runs. The results indicate that the calculated combustion zone temperatures and temperature profiles are in good agreement with the experimental data, for the range of oxygen concentration in the injected air. The use of oxygen-enriched air slightly increased the combustion front temperature from 440°C in a 21 mole % O2 concentration to a maximum of 475°C for air with 40 mole % O2 concentration. Oxygen-enriched air injection also increased the combustion front velocity from 13.4 cm/hr (for 21% oxygen) to 24.7 cm/hr (for 40% oxygen), thus reducing the start of oil production from 3.3 hours (for 21% oxygen) to 1.8 hours (for 40% oxygen). In the field, the use of oxygen-enriched air injection could translate into earlier oil production compared to with not-enriched air injection. The new analytical model for the combustion zone developed in this study will be beneficial to future researchers in understanding the effect of oxygen-enriched in-situ combustion and its implications on the combustion front temperature and combustion front thickness.

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Ara?jo, Edson de Andrade. "Estudo do processo de combust?o in-situ usando po?os horizontais como produtores de ?leo (Toe-to-Hell Air Injection)." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12965.

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The method "toe-to-heel air injection" (THAITM) is a process of enhanced oil recovery, which is the integration of in-situ combustion with technological advances in drilling horizontal wells. This method uses horizontal wells as producers of oil, keeping vertical injection wells to inject air. This process has not yet been applied in Brazil, making it necessary, evaluation of these new technologies applied to local realities, therefore, this study aimed to perform a parametric study of the combustion process with in-situ oil production in horizontal wells, using a semi synthetic reservoir, with characteristics of the Brazilian Northeast basin. The simulations were performed in a commercial software "STARS" (Steam, Thermal, and Advanced Processes Reservoir Simulator), from CMG (Computer Modelling Group). The following operating parameters were analyzed: air rate, configuration of producer wells and oxygen concentration. A sensitivity study on cumulative oil (Np) was performed with the technique of experimental design, with a mixed model of two and three levels (32x22), a total of 36 runs. Also, it was done a technical economic estimative for each model of fluid. The results showed that injection rate was the most influence parameter on oil recovery, for both studied models, well arrangement depends on fluid model, and oxygen concentration favors recovery oil. The process can be profitable depends on air rate
O m?todo toe-to-heel air injection (THAITM) ? um processo de recupera??o de petr?leo avan?ado, que consiste na integra??o da combust?o in-situ com os avan?os tecnol?gicos na perfura??o de po?os horizontais. Este m?todo utiliza po?os horizontais como produtores de ?leo, mantendo po?os injetores verticais para a inje??o de ar. Este processo ainda n?o foi aplicado no Brasil, tornando necess?rio, avalia??o destas novas tecnologias aplicadas ?s realidades locais, por isso, este trabalho teve como objetivo principal realizar um estudo param?trico do processo de combust?o in-situ com produ??o de ?leo em po?os horizontais, usando um reservat?rio semi sint?tico, com caracter?sticas das encontradas no Nordeste Brasileiro. As simula??es foram realizadas em um programa comercial de processos t?rmicos, denominado STARS (Steam, Thermal, and Advanced Processes Reservoir Simulator), da empresa CMG (Computer Modelling Group). Foram realizadas an?lises dos par?metros operacionais: vaz?es de inje??o, configura??o dos po?os e concentra??o de oxig?nio. O estudo de sensibilidade dos fatores foi realizado com a t?cnica de an?lise de planejamento experimental, com uma combina??o de dois e tr?s n?veis (32x22), totalizando 36 simula??es, 18 para cada modelo, em fun??o da produ??o acumulada de ?leo (Np). Tamb?m foi realizada uma estimativa econ?mica de an?lise de custo para cada modelo de fluido. Os resultados mostraram que a configura??o de po?os e a vaz?o de inje??o foram o par?metro que apresentou maior influ?ncia no ?leo recuperado para os dois modelos de fluidos analisados, respectivamente, que a configura??o de po?os ? influenciada pelo modelo de fluido, e que um aumento da concentra??o de oxig?nio favorece a recupera??o de ?leo, no processo estudado. Tamb?m foi encontrado que o processo pode ser rent?vel dependendo da quantidade de ar injetado no processo

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Catonho, Humberto Sampaio. "Estudo do processo de combust?o in-situ em reservat?rios maduros de ?leos m?dios e leves (high pressure air injection)." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12989.

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Nearly 3 x 1011 m3 of medium and light oils will remain in reservoirs worldwide after conventional recovery methods have been exhausted and much of this volume would be recovered by Enhanced Oil Recovery (EOR) methods. The in-situ combustion (ISC) is an EOR method in which an oxygen-containing gas is injected into a reservoir where it reacts with the crude oil to create a high-temperature combustion front that is propagated through the reservoir. The High Pressure Air Injection (HPAI) method is a particular denomination of the air injection process applied in light oil reservoirs, for which the combustion reactions are dominant between 150 and 300?C and the generation of flue gas is the main factor to the oil displacement. A simulation model of a homogeneous reservoir was built to study, which was initially undergone to primary production, for 3 years, next by a waterflooding process for 21 more years. At this point, with the mature condition established into the reservoir, three variations of this model were selected, according to the recovery factors (RF) reached, for study the in-situ combustion (HPAI) technique. Next to this, a sensitivity analysis on the RF of characteristic operational parameters of the method was carried out: air injection rate per well, oxygen concentration into the injected gas, patterns of air injection and wells perforations configuration. This analysis, for 10 more years of production time, was performed with assistance of the central composite design. The reservoir behavior and the impacts of chemical reactions parameters and of reservoir particularities on the RF were also evaluated. An economic analysis and a study to maximize the RF of the process were also carried out. The simulation runs were performed in the simulator of thermal processes in reservoirs STARS (Steam, Thermal, and Advanced Processes Reservoir Simulator) from CMG (Computer Modelling Group). The results showed the incremental RF were small and the net present value (NPV) is affected by high initial investments to compress the air. It was noticed that the adoption of high oxygen concentration into the injected gas and of the five spot pattern tends to improve the RF, and the wells perforations configuration has more influence with the increase of the oil thickness. Simulated cases relating to the reservoir particularities showed that smaller residual oil saturations to gas lead to greater RF and the presence of heterogeneities results in important variations on the RF and on the production curves
Aproximadamente 3 x 1011 m3 de ?leos m?dios e leves restar?o nos reservat?rios ao redor do mundo ap?s a aplica??o dos m?todos convencionais de recupera??o e grande parte desse volume seria recuper?vel com o uso de m?todos especiais. A combust?o in-situ (CIS) ? um m?todo de recupera??o avan?ada de petr?leo no qual um g?s que cont?m oxig?nio ? injetado no reservat?rio onde reage com o ?leo cru para criar uma frente de combust?o de alta temperatura que se propaga pelo reservat?rio. O m?todo HPAI (High Pressure Air Injection) ? uma denomina??o particular do processo de inje??o de ar aplicado em reservat?rios de ?leos leves, onde as rea??es de combust?o s?o dominantes entre 150 e 300?C e a gera??o de flue gas ? o principal fator de deslocamento do ?leo. Um modelo de simula??o de fluxo de um reservat?rio homog?neo foi constru?do para o estudo, o qual foi inicialmente submetido ? produ??o prim?ria, por 3 anos, e em seguida, ao processo de inje??o de ?gua por mais 21 anos. Nesse ponto, com a condi??o madura estabelecida no reservat?rio, foram selecionadas tr?s varia??es desse modelo, de acordo com o fator de recupera??o (FR) obtido, para o estudo da t?cnica de combust?o in-situ (HPAI). Em seguida realizou-se uma an?lise de sensibilidade sobre o FR de par?metros operacionais pr?prios do m?todo: vaz?o de inje??o de ar por po?o, concentra??o de oxig?nio no g?s injetado, esquema de inje??o de ar e configura??o dos canhoneados dos po?os. Essa an?lise, para um per?odo adicional de at? 10 anos produ??o, foi efetuada com o aux?lio da t?cnica de planejamento composto central. O comportamento do reservat?rio e os impactos de par?metros envolvendo as rea??es qu?micas e de particularidades de reservat?rio sobre o FR tamb?m foram avaliados. Adicionalmente foram elaborados uma an?lise econ?mica e um estudo de maximiza??o do FR do processo. As simula??es foram realizadas com o simulador de processos t?rmicos em reservat?rios STARS (Steam, Thermal and Advanced Process Reservoir Simulation) da CMG (Computer Modelling Group). Os resultados mostraram que os FR incrementais foram baixos e que o valor presente l?quido (VPL) ? impactado negativamente pelos elevados investimentos iniciais para compress?o do ar. Observou-se que a ado??o de maiores concentra??es de oxig?nio no g?s injetado e do esquema de inje??o de ar tipo five spot tende a favorecer o FR, e que a configura??o dos canhoneados dos po?os apresenta influ?ncia crescente com o aumento da espessura porosa com ?leo do reservat?rio. Casos simulados referentes ?s particularidades de reservat?rio indicaram que menores satura??es residuais de ?leo ao g?s levam a FR maiores e que a exist?ncia de heterogeneidades resulta em varia??es consider?veis nos FR e nas curvas de produ??o

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Zavala, Rosmery Violeta Quispe. "Ondas viajantes para combustão in-situ com efeito de perdas térmicas em meios porosos." Universidade Federal de Juiz de Fora (UFJF), 2018. https://repositorio.ufjf.br/jspui/handle/ufjf/8003.

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Apresentamos um modelo para a injeção de ar em um meio poroso que contém combustível sólido levando em conta as perdas térmicas para rocha circundante. Em trabalhos anteriores, o modelo foi simplificado e todas as sequências de ondas para a solução de problemas de Riemann foram obtidas sem levar em conta as perdas térmicas. Nesse trabalho, é feito um primeiro passo para entender o efeito das perdas de calor, que são importantes especialmente em experimentos de laboratório. Para provar a existência e unicidade da solução de ondas viajantes, os efeitos de difusão e a dependência da densidade do gás na temperatura são desconsiderados. Também são apresentadas simulações numéricas que validam os resultados obtidos, bem como simulações numéricas para um sistema mais geral que considera termos difusivos. Por fim são comparadas as soluções numéricas para ambos sistemas e um exemplo numérico com valores típicos dos parâmetros para um modelo de combustão é apresentado.
We present a model for the injection of air into an underground porous medium that contains a solid fuel. In previous works the model was simplified and all wave sequences for the Riemann problem solution were obtained without taking into account thermal losses to the surrounding rock. In that work the first step was made to understand the effect of heat losses, which are important especially in laboratory experiments. In order to prove of the existence and uniqueness of the traveling wave solution, diffusion effects and the dependence of gas density on temperature were disregarded. We will also present numerical simulations that validate the results obtained, as well as numerical simulations for a more general system that considers diffusive terms. Furthermore, we will compare the numerical solutions for both systems and a numerical example with typical values of the parameters for a combustion model is presented.

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Arif, Muhamad Fatikul. "Mécanismes d’endommagement du polyamide-66 renforcé par des fibres de verre courtes, soumis à un chargement monotone et en fatigue : Influence de l’humidité relative et de la microstructure induite par le moulage par injection." Thesis, Paris, ENSAM, 2014. http://www.theses.fr/2014ENAM0008/document.

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Le présent travail s'appuie sur une approche expérimentale étendue visant l'identification des mécanismes d'endommagement en chargement quasi-statique et en fatigue du PA66/GF30, en prenant notamment en compte l'influence de la teneur en eau et de la microstructure induite par le moulage par injection. Les essais et les observations in situ au MEB mettent en exergue le rôle déterminant de l'humidité relative sur l'initiation, le niveau et la chronologie de l'endommagement. Une analyse par micro-tomographie aux rayons X sur des échantillons ayant subi un chargement de fatigue montre que l'endommagement augmente continuellement et progressivement au cours de la fatigue, et plus significativement dans la deuxième moitié de sa durée de vie. Les résultats obtenus en quasi-statique et en fatigue révèlent des mécanismes d'endommagement similaires, notamment une décohésion des interfaces fibre/matrice. Une chronologie générale de l'endommagement est établie. Celui-ci s'initie en extrémités de fibres ou plus globalement là où les fibres sont relativement proches les unes des autres. Il s'ensuit des décohésions interfaciales se propageant le long des fibres. A une contrainte en flexion plus élevée, des microfissures de la matrice peuvent apparaître et se propager par coalescence, ce qui aboutira à la rupture. Ces résultats expérimentaux permettent d'alimenter une modélisation multi-échelles de l'endommagement à fort contenu physique. Celle-ci contribuera alors à une prédiction pertinente de l'endommagement dans les thermoplastiques renforcés pour application automobile
The current work focuses on extensive experimental approaches to identify quasi-static and fatigue damage behavior of PA66/GF30 considering various effects such as relative humidity and injection process induced microstructure. By using in situ SEM tests, it was observed that relative humidity conditions strongly impact the damage mechanisms in terms of their initiation, level and chronology. The X-ray micro-tomography analysis on fatigue loaded samples demonstrated that the damage continuously increases during fatigue loading, but the evolution occurs more significantly in the second half of the fatigue life. From the results of damage investigation under quasi-static and fatigue loading, it was established that both loading types exhibit the same damage mechanisms, with fiber/matrix interfacial debonding as the principal damage mechanisms. General damage chronologies were proposed as the damage initiates at fiber ends and more generally at locations where fibers are relatively close to each other due to the generation of local stress concentrations. Afterwards, interfacial decohesions further propagate along the fiber/matrix interface. At high relative flexural stress, matrix microcracks can develop and propagate, leading to the damage accumulation and then the final failure. The experimental findings are important to provide a physically based damage mechanisms scenarios that can be integrated into multiscale damage models. These models will contribute towards reliable predictions of damage in reinforced thermoplastics for lightweight automotive applications

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Elalaoui, Abdellah. "Synthèse de zéolithes à partir de solutions aqueuses contenant des ions fluorurés, en système clos par décomposition in situ de bases-retard ou ouvert, par injection de composés basiques ou acides." Mulhouse, 1993. http://www.theses.fr/1993MULH0275.

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L'objet de ce travail est d'étudier les possibilités offertes par l'exploitation d'une méthode de synthèse de zéolithes originale. La synthèse hydrothermale a lieu à partir de solutions aqueuses stables contenant généralement des ions F-, la génération d'espèces polycondensables étant produite grâce à la modification du pH initial. Cette modification du pH peut être provoquée soit suite à la décomposition in situ d'un modificateur de pH (système clos) soit suite à l'injection dans le système réactionnel de composés basiques ou acides (système ouvert). L'emploi de tels systèmes permet à priori d'espérer contrôler, contrairement au cas habituel ou des gels sont employés, la concentration en espèces polycondensables (sursaturation) dans le milieu, et donc finalement les phénomènes de cristallisation (nucléation et croissance). Les nombreuses variantes de la méthode ont été appliquées essentiellement à la synthèse de la zéolithe de type MFI. Dans chaque cas l'influence des paramètres physiques et chimiques a été examinée. En règle générale la formation de cristaux est accompagnée ou précédée de celle du gel sauf peut-être dans le cas particulier ou le mélange réactionnel contient une quantité importante de germes. Dans certaines conditions des cristaux d'une longueur supérieure à 1 mm ont été obtenus. Les caractérisations effectuées montrent que l'accélération de la cinétique de cristallisation va de pair avec l'augmentation de la densité de défauts dans les cristaux formés. Cette méthode de synthèse a aussi été appliquée à la préparation de la zéolithe Nu-1. Dans nos milieux réactionnels agités la présence des espèces F- et dipropylamine s'avère nécessaire à côté de celle des ions tétraméthylammonium habituels. L'ion F- semble occuper une position spécifique dans la charpente ; le rôle de la dipropylamine, non incorporée à la structure, est difficile à définir

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Manivannan, Sivaprasath. "Measuring permeability vs depth in the unlined section of a wellbore using the descent of a fluid column made of two distinct fluids : inversion workflow, laboratory & in-situ tests." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLX086/document.

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Dans les puits de production d’eau, de pétrole, de gaz et de chaleur géothermique, ou dans les puits d’accès à un stockage d’hydrocarbures, il est précieux de connaître la perméabilité de la formation ou de sa couverture en fonction de la profondeur, soit pour améliorer le modèle de réservoir, soit pour choisir les zones dans lesquelles procéder à des opérations spéciales.On propose une technique qui consiste à balayer la hauteur du découvert par une interface entre deux liquides de viscosités très contrastées. Le débit total qui pénètre la formation à chaque instant est ainsi une fonction de la position de l’interface et de l’historique des pressions dans le puits. On doit alors résoudre un problème inverse : rechercher la perméabilité fonction de la profondeur à partir de l’historique des débits dans le temps. Dans la pratique, le puits est équipé d’un tube central. Le balayage est effectué par injection d’un liquide à pression d’entrée constante dans le tube central et soutirage d’un autre liquide par l’espace annulaire. On mesure les débits d’injection et de soutirage dont la différence est le débit qui entre dans la formation.Pour valider et améliorer cette technique, on a d’abord utilisé une maquette simulant un découvert multi-couches disponible au LMS. On a exploité aussi des essais en place réalisés dans la couverture peu perméable d’un stockage souterrain de gaz. Dans ces essais, un liquide visqueux placé dans le découvert était déplacé par un liquide moins visqueux (méthode dite « opening »). Les couches plus perméables étaient correctement identifiées (Manivannan et al. 2017), mais une estimation quantitative était un défi en raison des phénomènes transitoires qui affectent le voisinage immédiat des puits. De plus, le rayon investigué dans le massif était petit.La thèse a relevé ces défis en proposant un essai légèrement différent et une nouvelle technique d’interprétation. Les essais avec une maquette modifiée ont montré la supériorité d’une méthode « closing » dans laquelle le puits est d’abord rempli du liquide le moins visqueux. On ménage une période de stabilisation avant l’injection du liquide visqueux pour réduire les effets transitoires ; elle permet aussi d’estimer la perméabilité moyenne et l’influence de la zone endommagée à la paroi (le « skin »).Puis on conduit l’essai proprement dit. L’historique des débits mesurés en tête de puits constitue le profil d’injection dont on déduit le profil de perméabilité.. Cette estimation suppose un écoulement monophasique dans chaque couche et la même « skin » pour toute la formation. Les incertitudes principales portent sur les pressions de formation et les variations possibles du « skin ». Elles sont estimées au moyen d’un calcul analytique. On a vérifié sur la maquette que les profils de perméabilité estimés présentent une bonne concordance avec les perméabilités mesurées avant les essais.On a réalisé un essai sur un sondage de 1750 m de long atteignant une couche de sel dont on a correctement estimé la perméabilité moyenne pendant la période de stabilisation. Toutefois elle était si faible (4.0E-21 m²) que l’utilisation de deux fluides n’a pas permis de faire une différence entre les diverses parties du puits
In wells producing water, oil, gas or geothermal energy, or in access wells to hydrocarbon storage, it is critical to evaluate the permeability of the formation as a function of depth, to improve the reservoir model, and also to identify the zones where additional investigation or special completions are especially useful.A new technique is proposed, consisting of scanning the open hole (uncased section of the wellbore) with an interface between two fluids with a large viscosity contrast. The injection rate into the formation depends on interface location and well pressure history. An inverse problem should be solved: estimate permeability as a function of depth from the evolution of flow rates with time. The wells are usually equipped with a central tube. The scanning is done by injecting a liquid in the central tube at constant wellhead pressure. Injection and withdrawal rates are measured at the wellhead; the difference between these two rates is the formation injection rate.To validate and improve this technique, we used a laboratory model mimicking a multi-layer formation, already available at LMS. We also made use of in-situ tests performed on an ultra-low permeable cap rock above an underground gas storage reservoir. In these tests, a viscous fluid contained in the open hole was displaced by a less-viscous fluid (a method called opening WTLog). The more permeable layers were correctly identified (Manivannan et al. 2017), but a quantitative estimation was challenging due to transient phenomena in the vicinity of the wellbore (near-wellbore zone). In addition, the investigation radius was small.These challenges are addressed by proposing a slightly modified test procedure and a new interpretation workflow. Laboratory tests with a modified test setup showed the advantages of the ‘closing’ method in which the well is filled with a less-viscous fluid at the start of the test. We also added a stabilization period before the injection of viscous fluid to minimize the transient effects; this period is also used to estimate the average permeability of the open hole and the effect of near-wellbore damage (skin).Then the test proper is performed (closing WTLog). The injection profile of the less-viscous fluid is computed from the wellhead flow rate history. A permeability profile is estimated from the injection profile. The permeability estimation considers a monophasic flow in each layer and the same skin value for all the formation layers. Major uncertainties in the permeability estimates are caused by formation pressures and heterogeneities in skin values; they are estimated using an analytical formula. We have verified on the laboratory setup that the estimated permeability profiles are well correlated to the permeabilities measured before the tests.An attempt was made to perform a WTLog in a 1750-m long wellbore opening in a salt formation. The first phase was successful and the average permeability was correctly assessed. However, this permeability was so small (4.0E-21 m² or 4 nD) that the gauges and the flowmeters were not accurate enough to allow a clear distinction between the permeabilities of the various parts of the open hole

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Evans, Daniel Christopher. "Predicting Injection Site Drug Precipitation." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/312666.

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Administering drug therapy through the intravenous route ensures rapid, and complete, bioavailability, which can be critical in an emergency situation. However, bypassing all of its protective barriers leaves the body vulnerable to harm if the parenteral formulation becomes unstable when mixed with the blood. An example of this formulation instability is the precipitation of poorly water-soluble drugs after mixing with the blood's aqueous environment. This happens when parenteral formulations rely too heavily upon the solution pH, and excipients, to increase the drug solubility. This precipitation in the blood can damage venous cell membranes producing symptoms ranging from mild skin irritation to death. To screen potential drug formulations for problems such as injection site drug precipitation, pharmaceutical companies have traditionally used costly and time consuming animal studies. To reduce the amount of pre-clinical animal studies necessary to find an optimal IV formulation, an in vitro device to detect injection site drug precipitation is introduced. In addition to the device, software that simulates the dilution of a parenteral drug formulation with blood upon administration has been developed and is introduced. Both the device and software were tested on commercially available formulations plus one formulation currently in clinical trials. The results and capabilities of the new device were compared to those obtained using an earlier in vitro device. Finally, a robust model for early screening of injection site precipitation is developed using both the in vitro device and software.

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Galhardo, Cristiane Xavier. "Potencialidade da injeção seqüencial no monitoramento em tempo real de indicadores de qualidade de águas naturais e residuais." Universidade de São Paulo, 2001. http://www.teses.usp.br/teses/disponiveis/46/46133/tde-10102014-131230/.

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O presente trabalho apresenta o desenvolvimento de metodologias baseadas no sistema de Análise por Injeção Seqüencial (SIA) para a determinação de fosfato e silicato, nitrito e nitrato, assim como a especiação de Fe(II) e Fe(III) em amostras de interesse ambiental, com ênfase para sistemas aquáticos. Para todas as determinações utilizou-se a espectrofotometria de absorção molecular na região do visível como técnica de detecção. A determinação de fosfato e silicato foi baseada na reação de ambos os ânions com molibdato de amônio em meio ácido e posterior redução do Mo(VI) à Mo(V) com ácido ascórbico. O procedimento SIA foi desenvolvido para contornar a interferência mútua das duas espécies explorando o efeito de complexação do molibdato pelo ácido oxálico. A determinação de nitrito foi baseada na reação de diazotação com sulfanilamida e diclorato de N-1 naftil etilenodiamina (NED), enquanto a determinação de Fe(II) baseou-se na sua complexação com 1,10 fenantrolina. A determinação de nitrato e Fe(III) foi efetuada pelas mesmas reações após a redução a nitrito e Fe(II) em colunas de cádmio e zinco amalgamado, respectivamente. A estabilidade das curvas analíticas foi avaliada em diferentes dias de trabalho, obtendo-se variações não superiores a 5% durante um período de 4 dias. O sistema de injeção seqüencial foi explorado também no sentido de regenerar as colunas redutoras no intervalo de tempo entre duas amostras. A estabilidade das curvas analíticas, a viabilidade de regeneração das colunas redutoras e a possibilidade de realizar a amostragem através de filtração tangencial, permitindo a realização de análises com características de tempo real, sugerem que o sistema de injeção seqüencial tem grande potencial para ser implementado em estações automáticas de monitoramento da fração solúvel de indicadores de poluição em águas naturais e residuais.
The present work presents the development of analytical methodologies based on Sequential Injection Analysis (SIA) for determination of phosphate and silicate, nitrite and nitrate, as well as speciation Fe(II)/Fe(III) in environmental samples with emphasis for aquatic environments. All determinations were performed using molecular absorption spectrophotometry at the visible range of the spectrum as the detection technique. The determination of phosphate and silicate was based on the reaction of both anions with ammonium molybdate in acidic medium, followed by reduction of Mo(VI) to Mo(V) with ascorbic acid. The SIA procedure was developed to avoid the mutual interference of both species exploiting the complexation of the molybdate by oxalic acid. The determination of nitrite was based on the diazotation reaction with sulfanilamide and N-l naphtyl ethylenediamine dihydrochlorine (NED), while the determination of Fe(II) were based on the complexation with 1,10 phenantroline. The determination of nitrate and Fe(III) were based on the same reactions, performed after their reduction to nitrite and Fe(II) in reducing columns containing cooperized cadmium and amalgamated zinc, respectively. The stability of the analytical curves was evaluated in different working days, in which no variations greater than 5% were observed during a period of 4 consecutive days. The sequential injection analysis was exploited to regenerate the reducing columns in the time interval between two sample. The stability of the analytical curves, the easy and automatic regeneration of the reducing columns, as well as the possibility to perform sampling through tangential filtration, which permits the analysis to be performed in real time, are characteristics that show the potential application of the sequential injection systems in automatic stations for monitoring the soluble fraction of pollution indicators in natural waste waters.

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29

Loulier, Karine. "Etude de la voie de signalisation Sonic Hedgehog et du contrôle de la prolifération cellulaire dans le cerveau mature de rongeurs." Phd thesis, Université Paris Sud - Paris XI, 2005. http://tel.archives-ouvertes.fr/tel-00429497.

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La voie de signalisation du morphogène Sonic Hedgehog (Shh) met en jeu des processus complexes étudiés, jusque là principalement, au cours du développement embryonnaire, où Shh est primordial pour le développement du tissu nerveux. Shh transmet son action via le complexe-récepteur Patched/Smoothened (Ptc/Smo) et le facteur de transcription Gli1, et interagit avec la glycoprotéine Hip (Hedgehog interacting protein) proposée comme antagoniste des protéines Hedgehog. Des analyses biochimiques ont permis de montrer qu'en plus de la forme membranaire, une forme soluble de Hip existe, notamment dans le cerveau adulte, et inhibe la voie de signalisation Shh in vitro. Par ailleurs, une cartographie de Hip dans le cerveau de souris embryonnaire (E13.5) et adulte supporte l'hypothèse que Hip interviendrait dans la régulation négative de la voie Shh. Enfin l'expression de Hip dans des cellules exprimant l'enzyme de synthèse de l'oxide nitrique (NO) dans le cerveau mature suggère des interactions entre les voies de signalisation impliquant respectivement Hip et le neuromédiateur gazeux NO. Pour étudier le rôle de Shh in vivo sur les progéniteurs neuraux du cerveau mature, la protéine recombinante ShhN a été injectée par stéréotaxie dans le ventricule latéral (VL) de souris adultes. En plus d'une forte activation de la voie Shh, reflétée par l'augmentation de la transcription de Ptc et Gli1 dans plusieurs régions cérébrales, telles que la zone sous ventriculaire (ZSV), le striatum, le septum latéral, le corps calleux et le cortex cérébral, le nombre de cellules ayant incorporé le marqueur de prolifération Bromodésoxyuridine (BrdU), est augmenté d'un facteur 3-4 dans le corps calleux et le cortex cérébral des souris ayant reçu la protéine Shh en comparaison avec des souris contrôles. Une telle augmentation n'a pas été observée dans la ZSV, une aire de neurogenèse majeure chez l'adulte. Par ailleurs, deux jours après l'injection de ShhN, un nombre significativement plus important de cellules en prolifération exprimant le protéoglycan membranaire NG2, marqueur des précurseurs oligodendrocytaires, est observé dans le cortex cérébral des souris ayant reçu la protéine ShhN. Afin d'analyser l'effet à long terme de la surexpression continue de la protéine Shh, un vecteur adénoviral Ad5-hShh-ires-eGFP destiné à exprimer la forme humaine de la protéine Shh a été développé puis caractérisé in vitro. Ce vecteur a ensuite été délivré dans le VL de cerveau de souris adultes et quatre jours après, la protéine Shh a été détectée dans les régions épendymaire et subépendymaire. Vingt-six jours après l'injection du vecteur Ad5-hShh-ires-eGFP, la voie Shh est toujours active comme révélé par la présence de nombreuses cellules exprimant le transcrit Gli1 dans plusieurs aires cérébrales. Une augmentation de 50% du nombre de cellules BrdU+ exprimant le marqueur oligodendroglial dm20+ est détectée dans le cortex cérébral et le corps calleux des souris ayant reçu le vecteur adénoviral Ad5-hShh-ires-eGFP par rapport aux souris ayant reçu le vecteur contrôle Ad5-eGFP. Dans leur ensemble, ces résultats suggèrent la capacité de la voie Shh à stimuler les cellules oligodendrocytaires pré-matures dans plusieurs régions du cerveau de rongeurs adultes. La modulation de cette voie apparaît donc potentiellement intéressante pour le traitement des maladies affectant le lignage oligodendrocytaire.

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30

Stendahl, Jonas. "Domain-Driven Security : Injection & Cross-site scripting." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-189326.

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Many web applications are vulnerable to Injection and Cross-site scripting. These attacks are often focused on infrastructural parts of the application. This thesis investigates if Domain-Driven Design can unify existing technical protection mechanisms as well as provide protection for attacks aimed at the business logic of an application. The performance of data validation and transformation performed with components from Domain-Driven Design is evaluated. The evaluation is performed by exposing an E-commerce application to dangerous injection and cross-site scripting strings. The data validation was found to be accurate and flexible and context mapping aided the understanding of correct data treatment depending on where in the application it is located or travelling to.

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31

ARIF, Muhamad Fatikul. "Mécanismes d'endommagement du polyamide-66 renforcé par des fibres de verre courtes, soumis à un chargement monotone et en fatigue : Influence de l'humidité relative et de la microstructure induite par le moulage par injection." Phd thesis, Ecole nationale supérieure d'arts et métiers - ENSAM, 2014. http://pastel.archives-ouvertes.fr/pastel-01064878.

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Le présent travail s'appuie sur une approche expérimentale étendue visant l'identification des mécanismes d'endommagement en chargement quasi-statique et en fatigue du PA66/GF30, en prenant notamment en compte l'influence de la teneur en eau et de la microstructure induite par le moulage par injection. Les essais et les observations in situ au MEB mettent en exergue le rôle déterminant de l'humidité relative sur l'initiation, le niveau et la chronologie de l'endommagement. Une analyse par micro-tomographie aux rayons X sur des échantillons ayant subi un chargement de fatigue montre que l'endommagement augmente continuellement et progressivement au cours de la fatigue, et plus significativement dans la deuxième moitié de sa durée de vie. Les résultats obtenus en quasi-statique et en fatigue révèlent des mécanismes d'endommagement similaires, notamment une décohésion des interfaces fibre/matrice. Une chronologie générale de l'endommagement est établie. Celui-ci s'initie en extrémités de fibres ou plus globalement là où les fibres sont relativement proches les unes des autres. Il s'ensuit des décohésions interfaciales se propageant le long des fibres. A une contrainte en flexion plus élevée, des microfissures de la matrice peuvent apparaître et se propager par coalescence, ce qui aboutira à la rupture. Ces résultats expérimentaux permettent d'alimenter une modélisation multi-échelles de l'endommagement à fort contenu physique. Celle-ci contribuera alors à une prédiction pertinente de l'endommagement dans les thermoplastiques renforcés pour application automobile.

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32

Gerlach, Bryce Mark. "Incidence and severity of Arcanobacterium pyogenes injection site abscesses with needle and needle-free injection methods." Thesis, Kansas State University, 2010. http://hdl.handle.net/2097/4644.

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Master of Science
Department of Animal Sciences and Industry
Terry A. Houser
Nursery age pigs (n=198) were used to evaluate the difference in the occurrence of injection site abscesses between needle-free jet injection and conventional needle-and-syringe injection systems. Pigs were fed for 21 d prior to treatment administration to acclimate the pigs to the environment of the Kansas State University Segregated Early Weaning (SEW) unit. On d 21 each pig was injected with aluminum hydroxide adjuvant in the neck and ham with needle-free jet injection (Pulse Needle-Free Systems, Lenexa, KS) and conventional needle-and-syringe injection. Needle-free and conventional needle-and-syringe injections were randomly assigned to pig side yielding a total of 396 injections per treatment with a total of 792 injections sites. Immediately prior to injection, the external surface of the injection sites were contaminated with an inoculum of Arcanobacterium pyogenes, a bacterium commonly associated with livestock abscesses. The pigs were then fed for a period of 27 or 28 d. On d 27 or d 28 the pigs were humanely euthanized and sent to the Kansas State Veterinary Diagnostics Laboratory where necropsies were performed and the injection sites harvested for histopathological evaluation. The needle-free jet injection system was associated with more injection site abscesses than the conventional needle-and-syringe injection method for both neck (P=0.0625) and ham (P=0.0313) injection sites. Twelve abscesses were found at injection sites administered via needle-free jet injection method while only 1 abscess was found with the conventional needle-and-syringe injection method. 5 abscesses were found at the neck injection sites and 8 abscesses were found at ham injection sites. There were no significant differences seen in tissue granulation resulting from reaction to the adjuvant. In summary, the implementation of needle-free jet injection systems in market hog production will be beneficial to eliminate needles and needle fragments in meat products but, when in the presence of Arcanobacterium pyogenes, it may increase the occurrence of injection site abscesses in pork carcasses that will need to be trimmed in pork processing plants. Although more abscesses were associated with needle-free jet injection, their occurrence was observed at a very low rate given that all injection sites were intentionally contaminated prior to injection.

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33

Robbins, Stephen Delbert. "Situating "evidence" and constructing users : communicative authority and the production of knowledge in harm reduction evaluation." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/5115.

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Despite thirty published evaluation reports citing the effectiveness of Vancouver’s safe injection site (Small 2008), the Canadian federal government refuses to endorse safe injection sites as a health service option available to injection drug users (IDUs). Insite’ s evaluation results are undergoing debate, because two communicative spheres of knowledge, each with a unique authoritative language, are conflicting as each is attempting to gain moral authority over the right to recontextualize drug users. Drawing on a literature review of two harm reduction programs in Vancouver, Insite and Sheway, and expert interviews with evaluators, I show that what constitutes “evidence” is in fact subjective, determined by spheres of communicability that are built upon social, professional and political contexts. To confront the problematic nature of this issue, I suggest that evaluators and overseers need to treat program evaluation as a process of negotiation, best approached in a fluid manner. By obscuring multiple user experiences in the evaluation of harm reduction programs, evaluators and overseers risk imposing their communicative ideologies on what it means to be a drug user.

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34

Nadeem, Muhammad. "Reservoir screening criteria for deep slurry injection." Thesis, University of Waterloo, 2005. http://hdl.handle.net/10012/1254.

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Deep slurry injection is a process of solid waste disposal that involves grinding the solid waste to a relatively fine-grained consistency, mixing the ground waste with water and/or other liquids to form slurry, and disposing of the slurry by pumping it down a well at a high enough pressure that fractures are created within the target formation. This thesis describes the site assessment criteria involved in selecting a suitable target reservoir for deep slurry injection. The main goals of this study are the follows:

Identify the geological parameters important for a prospective injection site
Recognize the role of each parameter
Determine the relationships among different parameters
Design and develop a model which can assemble all the parameters into a semi-quantitative evaluation process that could allow site ranking and elimination of sites that are not suitable
Evaluate the model against several real slurry injection cases and several prospective cases where slurry injection may take place in future

The quantitative and qualitative parameters that are recognized as important for making a decision regarding a target reservoir for deep slurry injection operations are permeability, porosity, depth, areal extent, thickness, mechanical strength, and compressibility of a reservoir; thickness and flow properties of the cap rock; geographical distance between an injection well and a waste source or collection centre; and, regional and detailed structural and tectonic setup of an area. Additional factors affecting the security level of a site include the details of the lithostratigraphic column overlying the target reservoir and the presence of overlying fracture blunting horizons. Each parameter is discussed in detail to determine its role in site assessment and also its relationship with other parameters. A geological assessment model is developed and is divided into two components; a decision tree and a numerical calculation system. The decision tree deals with the most critical parameters, those that render a site unsuitable or suitable, but of unspecified quality. The numerical calculation gives a score to a prospective injection site based on the rank numbers and weighting factors for the various parameters. The score for a particular site shows its favourability for the injection operation, and allows a direct comparison with other available sites. Three categories have been defined for this purpose, i. e. average, below average, and above average. A score range of 85 to 99 of 125 places a site in the ?average? category; a site will be unsuitable for injection if it belongs to the ?below average? category, i. e. if the total score is less than 85, and the best sites will generally have scores that are in the ?above average? category, with a score of 100 or higher. One may assume that for sites that fall in the ?average? category there will have to be more detailed tests and assessments. The geological assessment model is evaluated using original geological data from North America and Indonesia for sites that already have undergone deep slurry injection operations and also for some possible prospective sites. The results obtained from the model are satisfactory as they are in agreement with the empirical observations. Areas for future work consist of the writing of a computer program for the geological model, and further evaluation of the model using original data from more areas representing more diverse geology from around the world.

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35

Zhang, Kelly. "'No easy fix': The Supervised Injection Site Debate in Canada." Thesis, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31789.

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Supervised injection sites (SISs) have become subject to much political and social controversy in Canada since the late 1990s. Since the implementation of North America’s first SIS, Insite, in 2003 in Vancouver, the controversy has reached new levels. Despite the increasing evidence base available regarding the effectiveness of SISs as a harm reduction strategy trans-nationally, the implementation of this intervention in Canada prevails within public and parliamentary debates. Guided by the theoretical contributions of Joel Best (2008) on claims-making and the construction of social problems, this thesis explores the SIS debate in Canada and the assertions advanced with respect to the implementation of SISs. Building on the available literature, the author identifies numerous types of claims advanced by proponents and opponents of SISs through a qualitative content analysis of 164 newspaper documents from The Vancouver Sun, The Ottawa Sun and The Ottawa Citizen. It was determined that claimsmakers often present the intervention as a solution to the ‘drug problem’ or part in parcel of the problem. Opponents in particular attempt to construct the intervention as harmful for the community in that the implementation of a SIS would exacerbate various aspects of the ‘drug problem’ including drug abuse and crime. Very rarely, however, claimsmakers suggest the SIS is merely one strategy to addressing public health issues related to injection drug use and that there is ‘no easy fix’ to this ‘drug problem’. Further, the author applies the findings from this analysis to make sense of the Canadian federal government’s proposed policy response, The Respect for Communities Act, towards the establishment of SISs.

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36

Longo, M. "MULTI MODALITY IMAGING APPROACHES TO INJECTION-SITE SARCOMA IN CATS." Doctoral thesis, Università degli Studi di Milano, 2017. http://hdl.handle.net/2434/487980.

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The aim of this study was to investigate different diagnostic imaging approaches for Injection-Site Sarcomas in cats (ISS) and their mutual relationships with the surrounding tissues between December 2014 and October 2016. In the literature there is a lack of anatomical references about the interscapular region of the cat, with very few publications displaying the musculoskeletal anatomy in transverse sections. Computed Tomography (CT) has been proven to be useful in the staging process of feline patients affected by ISS, not only for correct estimation of the volumetric balance of the tumour but also for thorough staging of distant and local metastatic spread. ISS are mesenchymal soft tissue tumours characterized by a typical interscapular location and highly infiltrative behaviour. CT can be considered the modality of choice for ISS staging and a double positioning (dynamic approach) was reported to successfully detect the exact amount of infiltration of the muscles. A correct estimation of the spatial relationship between neoplastic, inflammatory and normal tissue is crucial, since the indicated treatment is mainly characterized by wide surgical excisions of the neoplasm, including 3-5 cm of perilesional tissues. Our study consists of an anatomic atlas of the interscapular region of the cat in a clinically normal population, using magnetic resonance imaging (MRI), computed tomography (CT) and gross sectional anatomy. In addition we compared both clinical and CT findings for pre-surgical assessment of the tumour. We performed a final volumetric estimation utilising dynamic double positioning in a cohort of 84 patients. Results from our study provide a new and dynamic way to investigate the interscapular region of the cat, with anatomical references for in vivo CT and MRI, considering muscular changes according to forelimb positioning. Analysing the discrepancy between clinical and CT tumour measurements there was a tendency for CT measurements to be greater than clinical dimensions, and this difference increased with increasing tumour size. Based on our results, further studies focusing on ISS in cats, should specify the kind of assessment used to define tumour dimensions (CT versus clinical examination) in order to interpret surgical results and prognostic impact of this variable. Finally, results from the investigation of the use of the dynamic approach in patients referred for pre-surgical staging of interscapular ISS demonstrated good agreement between observers, with higher tumour volumes detected via the ellipsoid method. Lower tumour volumes showed slightly decreased muscular infiltration. In conclusion, the dynamic approach should be performed for a complete evaluation of the invasiveness of the ISS along with an appropriate selection of tumour volume methodology, which could potentially affect the pre-surgical assessment of ISS.

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37

Lacrampe, Marie-France. "Ecoulement des polymères thermoplastiques dans le moule d'injection : Analyse expérimentale et validation d'un modèle de calcul." Valenciennes, 1993. https://ged.uphf.fr/nuxeo/site/esupversions/b265390d-1490-4919-bd16-24982b59b519.

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Cette étude a nécessité l'instrumentation de quatre outillages d'injection en capteurs de pressions et thermocouples. Nous avons montré que les débits volumiques moyens mesures pendant le remplissage sont différents des débits volumiques imposes, et que le paramètre le plus significatif est la géométrie de l'empreinte. Nous avons également montré que le débit volumique au front de matière évolue de façon significative pendant la phase de remplissage. Un modèle simple a permis d'attribuer ces différents phénomènes à la compressibilité du matériau et à sa viscosité de volume (tres supérieure à sa viscosité de cisaillement) qui ne sont généralement pas pris en compte lors des simulations de la phase de remplissage. Une étude paramétrique de l'influence des conditions de transformation, et de la géométrie de l'empreinte sur les pressions mesurées en fin de remplissage pour différents matériaux a été réalisée. La comparaison des résultats de cette étude à ceux des simulations correspondantes par un logiciel commercial de référence est en tendance satisfaisante. Les écarts calcul-mesuré pour des conditions de transformation extrêmes ont été attribué d'une part à l'utilisation par ce modèle d'une loi de comportement trop simple, et d'autre part à la méthode de calcul employée qui n'utilise pas de discrétisation dans l'épaisseur de l'empreinte. Une comparaison similaire a ponctuellement été réalisée sur l'évolution de la pression en différents points du disque d'épaisseur 2 mm pendant le remplissage. Elle a validé le choix de la pression de fin de remplissage comme critère de jugement de la qualité de la modélisation. Nous avons ponctuellement réalisé des simulations avec un logiciel plus élaboré. Les résultats obtenus sont similaires à ceux fournis pour cette géométrie par le logiciel de référence.

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38

Kopp, Andreas. "Evaluation of CO2 injection processes in geological formations for site screening." Stuttgart Inst. für Wasserbau, 2009. http://d-nb.info/996804145/34.

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39

Wu, Zimei, and n/a. "Formulation approaches to minimise injection site reactions of poorly soluble drugs." University of Otago. School of Pharmacy, 2006. http://adt.otago.ac.nz./public/adt-NZDU20070503.122315.

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Purpose: The aim of this study was to investigate the usefulness of formulation approaches to minimise injection site reactions for poorly soluble drugs. The specific objectives were to modify the injection site reactions by identification of irritant components in the formulation and control of their release kinetics; and to gain understanding of formulation approaches to create a favourable microenvironment in the tissues allowing better tissue tolerance and drug absorption. Methods: Physicochemical properties of the model drug, ricobendazole (RBZ) were characterised using conventional methods. Three formulation approaches to minimise irritancy of the low pH RBZ solution were assessed. An in vitro method using 96-well microplates and a microtiter plate reader was used for detection of drug precipitation on dilution for formulation characterisation. Cellular damage by the formulations was investigated in L929 fibroblasts using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxy phenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) and lactate dehydrogenase (LDH) assays. Tissue tolerance and pharmacokinetics were simultaneously investigated after subcutaneous injection in sheep. A low pH RBZ solution was used as a reference formulation. Results: Preformulation studies showed that RBZ was practically insoluble in water and oils, and was slightly soluble in commonly used co-solvents. Solubility was slightly improved by complexation with hydroxypropyl-β-cyclodextrin (HP-β-CD, K₁:₁ = 311 M⁻�) or a combination of low pH (> 2) with surfactants or co-solvents. A U-shaped pH-solubility profile in aqueous solutions indicated that RBZ is an ampholyte. pKa values measured by absorbance spectroscopy and pH solubility methods were 3.45 and 3.76 (basic) and 9.82 and 9.53 (acidic) respectively. The partition coefficient was 14.3 - 15.2 at pH 6 - 9 and less at higher or lower pH. In aqueous solutions, RBZ showed a V-shaped pH-degradation rate profile and was most stable at pH 4.8. Degradation pathways were identified as hydrolysis and oxidation. Three RBZ injectables (5%) were obtained by modification of the low pH RBZ solution; addition of 20% HP-β-CD, incorporation into a w/o emulsion, and a microemulsion (ME). On dilution with SPB, the onset time of drug precipitation was prolonged and the rate was reduced in the presence of HP-β-CD. The w/o emulsion had a low viscosity (< 60 mPa.s) and exhibited Newtonian flow. Drug release versus the square root of time was linear and the release rate could be adjusted by phase ratio and droplet size. Drug release was found to be by diffusion. A coarse emulsion layer appeared at the interface between the ME and buffer. Drug release from the ME was faster than from the emulsion and was linear with the square root of time. On titration into SPB, the three formulations showed controlling effects on the release of H₃O⁺ compared to the reference formulation. RBZ (0.1 mg/ml) was more toxic to L929 cells than the co-solvent propylene glycol (50 mg/ml). The formulations showed greater cytotoxicity than their vehicles in the order: ME > RBZ solution = emulsion > HP-β-CD. HP-β-CD and emulsion excipients showed little or no cytotoxicity. The MEs exhibited more toxicity in the LDH assay than in the MTS assay. A reversed phase HPLC assay for simultaneous determination of RBZ and its metabolite in sheep plasma using an isocratic system with UV detection was developed and used in the pharmacokinetic studies. Plasma samples were prepared by solid phase extraction. A suitable internal standard was selected by quantitative structure-retention relationships analysis. The composition of a ternary mobile phase was optimised with the assistance of multiple linear regression. The assays were linear over the concentration range 10 - 1000 ng/ml for both analytes (r > 0.999) with satisfactory inter-day and intra-day precision and accuracy (CV < 10%). The recoveries for all analytes were > 96%. A pilot study in sheep suggests that injection of the vehicles (the CD, emulsion and ME) caused virtually no pain on injection or site reactions. Both the reference formulation and its vehicle induced pain on injection and resulted in swollen tissues. Histology after two weeks showed granulation for the formulation, but not the vehicle. In contrast, animals showed virtually no injection site reactions with the ME and emulsion. The HP-β-CD formulation gave transient pain on injection but a two-fold increase in bioavailability compared with the reference. The emulsion produced sustained drug release and increased drug absorption. In the main study, the HP-β-CD vehicle showed good tissue compatibility. Irritation by the HP-β-CD formulation was attributed to the low pH. Cmax, tmax and AUC0-[infinity] for the reference formulation were 1.3 � 0.3 [mu]g/ml, 9.6 � 2.9 h and 36.7 � 9.2 [mu]g�h/ml respectively, while the corresponding data for the HP-β-CD formulation were 2.9 � 0.8 [mu]g/ml, 5.0 � 0.6 h and 54.5 � 15.3 [mu]g�h/ml respectively. The half-life following the injection of the HP-β-CD formulation (5.5 � 2.8 h) was shorter than that of the reference formulation (8.5 � 3.4 h). Conclusions: Injection site reactions may be minimised by identification of irritant components in a formulation and by controlling their release. Controlling the burst release of the poorly water soluble drug RBZ in a low pH solution could improve tissue tolerance and minimise post-injection precipitation, and hence increase drug bioavailability. In addition, HP-β-CD was a useful local injectable carrier which significantly enhanced the absorption of RBZ after subcutaneous injection in sheep.

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40

Dean, Rachel Sarah. "The epidemiology of feline injection site sarcomas in the United Kingdom." Thesis, Royal Veterinary College (University of London), 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.558961.

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41

Mosca, Flaviana <1978&gt. "Activation of innate immunity by human vaccine adjuvants at injection site." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1409/1/Mosca_Flaviana_tesi.pdf.

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42

Mosca, Flaviana <1978&gt. "Activation of innate immunity by human vaccine adjuvants at injection site." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1409/.

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43

Abarca, Betancourt Alberto Javier. "The Stability of Uranium-Bearing Precipitates Created as a Result of Ammonia Gas Injections in the Hanford Site Vadose Zone." FIU Digital Commons, 2017. http://digitalcommons.fiu.edu/etd/3359.

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Uranium (U) is a crucial contaminant in the Hanford Site. Remediation techniques to prevent contaminant migration of U located in the soils to other important water resources such as the Columbia River are of paramount importance. Given the location of the contaminant in the deep vadose zone, sequestration of U caused by ammonia (NH3) gas injections appears to be a feasible method to decrease U mobility in the contaminated subsurface via pH manipulation, ultimately converting aqueous U mobile phases to lower solubility precipitates that are stable in the natural environment. This study evaluated the stability of those U-bearing precipitates via preparation of artificial precipitates mimicking those that would be created after NH3 gas injections and sequential extractions experiment. Results showed that most of the U was recovered with the extracting solutions targeted to remove uranyl silicates and hard-to-extract U phases, suggesting that U present in the solid particles has strong bonds to the vadose zone sediments, causing the precipitates to be stable and therefore the remediation technology to be effective under the simulated conditions.

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Scholte, Theodoor. "Amélioration de la sécurité par la conception des logiciels web." Thesis, Paris, ENST, 2012. http://www.theses.fr/2012ENST0024/document.

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L'internet est devenu un environnement omniprésent dans le monde du travail et du loisir. La popularité sans cesse croissante des applications web ainsi que des services associés entraînent l'exécution de nombreuses transactions critiques, qui soulèvent des questions de sécurité. Du fait de cette croissance, des efforts ont été entrepris durant cette dernière décennie pour rendre les applications web plus sûres. Malgré ces efforts, de récents rapports provenant de l'institut SANS estiment que plus de 60 % des attaques commises sur l'Internet ciblent les applications web en se concentrant sur les vulnérabilités inhérentes aux problèmes de validation, comme le Cross-Site Scripting ou les injections SQL. Dans cette thèse, nous avons conduit deux études de recherche empirique, analysant un grand nombre d'application web vulnérables. Nous avons assemblé une base de données contenant plus de 10.000 rapports de vulnérabilités depuis l'an 2000. Ensuite, nous avons analysé ces données pour déterminer si les développeurs ont pris conscience des problématiques de sécurité web de nos jours, comparé à la période où ces applications émergeaient. Puis nous avons analysé l'étroit lien entre le langage de programmation utilisé pour développer l'application web et le nombre de vulnérabilité reporté. Avec ces résultats empiriques comme base, nous présentons notre solution IPAAS qui aide les développeurs novice en termes de sécurité à écrire des applications sécurisées par défaut. Nous montrons par ailleurs que cette technique améliore de manière probante la sécurité des applications web
The web has become a backbone of our industry and daily life. The growing popularity of web applications and services and the increasing number of critical transactions being performed, has raised security concerns. For this reason, much effort has been spent over the past decade to make web applications more secure. Despite these efforts, recent data from SANS institute estimates that up to 60% of Internet attacks target web applications and critical vulnerabilities such as cross-site scripting and SQL injection are still very common. In this thesis, we conduct two empirical studies on a large number of web applications vulnerabilities with the aim of gaining deeper insights in how input validation flaws have evolved in the past decade and how these common vulnerabilities can be prevented. Our results suggest that the complexity of the attacks have not changed significantly and that many web problems are still simple in nature. Our studies also show that most SQL injection and a significant number of cross-site scripting vulnerabilities can be prevented using straight-forward validation mechanisms based on common data types. With these empirical results as foundation, we present IPAAS which helps developers that are unaware of security issues to write more secure web applications than they otherwise would do. It includes a novel technique for preventing the exploitation of cross-site scripting and SQL injection vulnerabilities based on automated data type detection of input parameters. We show that this technique results in significant and tangible security improvements for real web applications

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Hassan, Mohamad. "Conversion en diesel-gaz d'un moteur diesel à injection directe de faible puissance." Valenciennes, 1992. https://ged.uphf.fr/nuxeo/site/esupversions/be2998f3-db38-4ee2-a7bd-e9ed853663aa.

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Nous étudions le problème de la conversion en diesel-gaz naturel d'un moteur diesel standard à injection directe de 55 kw et l'influence des principaux paramètres de fonctionnement. Les limites imposées pour les charges thermiques et les contraintes mécaniques sont celles du diesel. Il faut refroidir les injecteurs pour éviter leur grippage et pouvoir effectuer à tout moment la commutation diesel-gaz-diesel. Le taux d'injection pilote minimum acceptable pour un fonctionnement stable du moteur qui est de 7% avec les injecteurs d'origine peut être ramené à 2,5% avec des injecteurs monotrous.

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Sanderson, Alicia. "Insite as Representation and Regulation: A Discursively-Informed Analysis of the Implementation and Implications of Canada's First Safe Injection Site." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20113.

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This study consisted of a qualitative analysis of articles from two Canadian newspapers related to North America’s only safe injection facility for drug users, Vancouver’s Insite, and examined the texts for latent themes derived from a review of harm reduction and governmentality literature. The investigation asked “In what ways are Insite and its clients represented in the media and what implications do those portrayals have in terms of Insite’s operation as a harm reduction practice as well as a governmental strategy designed to direct the conduct of drug users who visit the site?” The analysis revealed conflicting representations, some which have positive potential in terms of Insite’s adherence to the fundamental principles of harm reduction and others that undermined those principles and suggested that the site may have traditional governmental functions, perhaps indicating less distance between the harm reduction and governmentality philosophies in the discourse surrounding the SIS than expected.

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47

Kopp, Andreas [Verfasser]. "Evaluation of CO2 injection processes in geological formations for site screening / von Andreas Kopp." Stuttgart : Inst. für Wasserbau, 2009. http://d-nb.info/996804145/34.

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48

Ivanova, Alexandra. "Geological Structure and Time-Lapse Studies of CO2 Injection at the Ketzin Pilot Site, Germany." Doctoral thesis, Uppsala universitet, Geofysik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-196127.

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3D seismic time-lapse surveys (“4D seismics”) are an essential tool for large scale reservoir characterization. The target reservoir of the Ketzin pilot project for CO2 storage is a saline aquifer of the heterogeneous Stuttgart Formation (Upper Triassic) in the Northeast German Basin. The focus of this project is on testing and further developing monitoring CO2 storage technologies. For time-lapse seismic monitoring, three seismic surface sources were characterized with respect to S/N (signal to noise) ratios, signal penetration, and frequency content by analysis of raw shot gathers and stacked sections along two lines at the Ketzin site. Differences in reflectivity between these 2D lines reflect the differences in the nature of the sources tested and how they influence the signal bandwidth (resolution) and signal energy. All three sources image the target horizon. The weight drop source was recommended as the primary source for 3D surveys based mainly on logistics and cost. Results of processing, including equalization of a 4D (3D time-lapse) data set from the Ketzin site and cross-correlation, indicate that the injected CO2 can be monitored. The highly irregular amplitude response on the time-lapse data can be attributed to the reservoir heterogeneity. Time-lapse seismic processing, petrophysical measurements on core samples and geophysical logging of CO2 saturation levels allow for an estimate of the total amount of CO2 visible in the seismic data to be made. In spite of some uncertainty, the close agreement between the injected and observed amount is encouraging for quantitative monitoring of a CO2 storage site using seismic methods. By integrating seismic modeling and multiphase fluid flow simulations, the impact of the reservoir temperature on the 4D seismic data from Ketzin was estimated. The modeled time-lapse seismic differences for two temperature scenarios present in the reservoir are minor regarding the qualitative analysis. However, the influence of temperature on the volumetric estimation of the CO2 using the 4D seismic data is significant. Future issues to be considered include expanding the temperature range (34-38°C in this study) to be investigated and the resulting effects on the seismic response, as well as the role of the reservoir heterogeneity. In addition, it would be important to investigate the impact of temperature on the CO2 storage at other sites with favorable P-T conditions in the reservoir. Further seismic modeling using results of petrophysical experiments for estimating the effect of the CO2 injection at the Ketzin site on the AVA/AVO response on time lapse seismic data was performed. Two effects were considered: the CO2-saturation- and the pore-pressure-related effects. The results indicate that it is worth investigating if it is possible to discriminate between these effects on future 3D repeat surveys at the Ketzin site.

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Caproni, Elena. "Distinctive innate immune signatures at injection site boost the adaptive response to flu subunit vaccine." Doctoral thesis, Università degli studi di Padova, 2011. http://hdl.handle.net/11577/3427448.

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Vaccine adjuvants activate specific innate immune pathways which boost the adaptive responses to co-administered antigens. Experimental data in mouse and human have shown that the efficacy of vaccine adjuvants is often antigen-dependent. For example, alum has been used for years as an efficient adjuvant for many subunit vaccines including Hepatitis B and Diphteria-Tetanus, but is not very efficient in enhancing the response to flu HA antigen. Recently, several human studies have shown that oil-in-water emulsions such as MF59 are superior to alum in enhancing the response to flu subunit vaccines. However, the mechanism of action of flu adjuvanticity is not fully understood. In this study we wanted to identify the innate immune signatures that are associated to adjuvanticity to flu subunit vaccine in the mouse system. First we immunized mice with seasonal trivalent flu antigens or tetanus toxoid (TT) mixed with MF59, alum or three TLR-dependent adjuvants: the oligonucleotide CpG (TLR9), the small molecule resiquimod (TLR7/8) and the lipopeptide Pam3CSK4 (TLR2). All adjuvants were similarly efficient in inducing an adaptive immune response to TT. By contrast, MF59 and, to a lesser extent, Pam3CSK4, enhanced the antibody responses to HA. In order to correlate innate immune gene signatures induced by the vaccine adjuvants with the ability to boost flu adaptive responses, we performed microarray analysis with the same set of adjuvants both in vitro in mouse splenocytes and in vivo in mouse muscle and draining lymph nodes. Unlike TLR agonists, MF59 and alum did not affect gene expression of blood cells in vitro and draining LN in vivo. On the other hand, MF59 was the strongest activator of cytokine, chemokine and leukocyte transendothelial migration genes in the muscle, suggesting an early and stronger cell recruitment potential. Indeed MF59 and Pam3CSK induced a stronger and more rapid recruitment of CD11b+ cells (monocytes, DCs and granulocytes) at injection site compared to the other adjuvants tested. It has been recently proposed that TLR7-dependent activation of the interferon type 1 pathway is the innate immune pathway required for adjuvanticity to flu vaccines. Surprisingly, we found that the TLR7 adjuvant resiquimod did not affect the adaptive response to flu despite a strong activation of the interferon pathway in the muscle and in the LNs. In summary, here we show that strong activation of innate immunity in the muscle, but not in draining LNs, and local recruitment of CD11b+ blood cells at injection site by MF59 and TLR2 vaccine adjuvants correlates with their ability to enhance antibody responses to flu antigens.
Studio in modello animale della regolazione trascrizionale indotta dalla somministrazione di alcune molecole con attività immunostimolatoria. In particolare il lavoro è focalizzato sull’effetto che ha l’emulsione MF59 sull’immunità innata a livello del sito di iniezione, rispetto ad altre classi di adiuvanti. Dati riguardanti la risposta anticorpale hanno dimostrato con MF59 sia il miglior adiuvante per gli antigeni dell’influenza rispetto agli altri adiuvanti classici come alum e CpG. Per questo si è deciso di investigare, tramite analisi microarray, l’effetto di MF59, rispetto alle altre molecole, a livello di espressione genica al sito di iniezione (nel muscolo) e distalmente (nel linfonodo). È stato osservato come MF59 sia il più forte attivatore di geni codificanti per chemochine e citochine al sito di iniezione, suggerendo un suo effetto sull’immunità innata. Essendo inoltre l’emulsione anche in grado di attivare l’espressione di geni codificanti per proteine coivolte nel pathway di migrazione transendoteliale e per i recettori delle chemochine, è stato selezionato il gene Itgam, codificante per l’integrina CD11b, appunto coinvolta in tale meccanismo: lo studio di localizzazione tramite microscopia confocale di sezioni di muscolo, ha evidenziato come MF59, rispetto agli altri adiuvanti, induca un “recruitment” di cellule CD11b+ al sito di iniezione. Inoltre la regolazione dell’espressione di alcuni marcatori di superficie in cellule del linfonodo è stata confermata mediante citofluorimetria.

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Johns, Martin [Verfasser], and Joachim [Akademischer Betreuer] Posegga. "Code Injection Vulnerabilities in Web Applications : Exemplified at Cross-site Scripting / Martin Johns. Betreuer: Joachim Posegga." Passau : Universitätsbibliothek der Universität Passau, 2011. http://d-nb.info/101488456X/34.

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Dissertations / Theses on the topic 'In situ injection'

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