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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Étude dynamique et effet du changement d'échelle pour plusieurs systèmes particulaires en mélangeur Turbula® : application à un mélange destiné à la fabrication de plaques composites / Dynamic study and impact of scale-up for different particulate system in Turbula mixer : application to a mixture use for composite plate manufacturing

Mayer-Laigle, Claire 02 July 2012 (has links)
L'optimisation d'une opération de mélange de poudre repose essentiellement sur un travail expérimental à l'échelle du laboratoire qui doit pouvoir être transposer aux mélangeurs de plus grandes tailles. Définir des lois d'extrapolation et améliorer notre connaissance de la dynamique du mélange est donc nécessaire. Dans ces travaux, la dynamique de mélange au sein des mélangeurs Turbula® a été étudiée en s'appuyant sur l'analyse des cinétiques de mélange et des fonctions d'autocorrélation pour plusieurs systèmes particulaires. Selon les vitesses de rotation de l'axe moteur, 3 régimes d'écoulement ont été définis et les principaux mécanismes de mélange et de ségrégation apparaissant pour chacun de ces régimes ont été identifiés en lien avec les propriétés d'écoulement des produits. Dans un deuxième temps, les qualités de mélange obtenues dans différentes tailles de mélangeurs ont été comparées sur la base du principe des similitudes afin de mettre en évidence les facteurs ayant une influence lors du passage d'une taille de mélangeur à une autre. Enfin dans le cadre d'une application industrielle, une méthodologie s'appuyant sur l'intensité de ségrégation et l'autocorrélation spatiale, a été développée pour identifier des défauts d'homogénéité au sein de plaques bipolaires composites / The optimization of a powder mixing step typically involves an experimental work at lab scale in order to be transposed to larger mixers. Defining scale-up laws and improving our knowledge of the mixing dynamics remains some of the mains industrial issues of this century. In this work, the mixing dynamics of several particulate systems has been studied in Turbula mixers thanks to the analysis of mixing kinetics and autocorrelation functions. According to the engine speed, three flow regimes have been defined. The corresponding main mixing and segregation mechanisms at play for each of these regimes have been identified in relation with the flow properties of the products. In a second phase, the qualities of the mixtures obtained in the different mixer sizes have been compared on the basis of the principle of similarities in order to shed light the factors which influencing scale-up. Finally, as part of an industrial application, a methodology has been developed using the concept of intensity of segregation and the spatial autocorrelation tools to identify heterogeneities in bipolar plates made of composite materials
72

Scale-up d'un procédé continu aérobie à lit fluidisé granulaire pour le traitement des effluents / Scale-up of a fluidized bed reactor for effluent treatment by aerobic granular sludge

Henriques, Justine 21 March 2019 (has links)
Pour faire face à des réglementations de plus en plus contraignantes, des procédés compacts et performants doivent être développés pour assurer un traitement des effluents efficace et pérenne. La technologie des boues granulaires aérobies permet de coupler productivité et compacité pour autant qu’elle soit maîtrisée. La formation des granules implique des conditions opératoires définies principalement dans des réacteurs discontinus. Afin d’améliorer la capacité de traitement, ce travail a pour objectif de proposer des conditions opératoires permettant l’utilisation des boues granulaires aérobies dans un réacteur en régime continu. Pour cela, la technique de granulation de l’écosystème est contrôlée par l’optimisation du fonctionnement d’un réacteur de laboratoire fonctionnant en discontinu (mode transitoire) puis la procédure obtenue est transposée à une taille de réacteur plus importante. Cette étude montre que la charge massique, le cisaillement et la pression de sélection des boues conditionnent la formation des granules et leurs propriétés. Le fonctionnement du réacteur en régime continu a ensuite été étudié. Il est montré que la structure granulaire a pu être maintenue tout en augmentant l’efficacité du procédé, tout paramètre équivalent par ailleurs (capacité de traitement doublée pour le réacteur continu). In fine, le système a été testé avec un effluent industriel. Un logiciel industriel a été utilisé afin de représenter pour l’optimiser le fonctionnement d’un réacteur fluidisé granulaire tel qu’obtenu expérimentalement. Si le module proposé dans ce logiciel a montré ses limites pour simuler un régime SBR, le modèle MBBR , bien que ne considérant pas la granule dans son ensemble, semble être adéquat pour représenter le fonctionnement en continu. L’utilisation des boues granulaires dans un réacteur continu est une technologie prometteuse mais nécessite des investigations sur son fonctionnement à long terme et sa modélisation. / Due to more stringent regulations, wastewater processes need to be more compact and effective. The utilization of aerobic granular sludge conjugates compactness and productivity with the control of the operational. Granulation, which need specific conditions, are mostly operated in batch reactors. To improve the capacity of treatment, this study investigates process conditions for an optimal operation for a continuous reactor working with aerobic granular sludge. First of all, granulation technique is optimized in a laboratory batch reactor (SBR) and results reveal that food to microorganism ratio, shear and selection pressure applied influence pellets’ formation and their properties. Then, this optimized method is successfully scaled-up. After that, the utilization of granules in continuous is studied and this mode increases the reactor capacity while the granular structure is maintained. The utilization of an industrial influent shows reserved results. A commercial software was used to simulate experimental results obtained for a fluidized reactor using pellets. The model, proposed by the software, shows inconsistencies in batch mode. The MBBR model seems more appropriate to simulate continuous mode although the whole pellet is not considered. So, the utilization of aerobic granular sludge in a continuous reactor is a promising technology but further research is needed in the long term operation and its modeling.
73

Control of Proteolysis of Recombinant Proteins in Escherichia coli

Rozkov, Aleksei January 2001 (has links)
No description available.
74

Control of Proteolysis of Recombinant Proteins in Escherichia coli

Rozkov, Aleksei January 2001 (has links)
No description available.
75

Modeling conformance control and chemical EOR processes using different reservoir simulators

Goudarzi, Ali 16 September 2015 (has links)
Successful field waterflood is a crucial prerequisite for improving the performance before EOR methods, such as ASP, SP, and P flooding, are applied in the field. Excess water production is a major problem in mature waterflooded oil fields that leads to early well abandonment and unrecoverable hydrocarbon. Gel treatments at the injection and production wells to preferentially plug the thief zones are cost-effective methods to improve sweep efficiency in reservoirs and reduce excess water production during hydrocarbon recovery. There are extensive experimental studies performed by some researchers in the past to investigate the performance of gels in conformance control and decreasing water production in mature waterflooded reservoirs, but no substantial modeling work has been done to simulate these experiments and predict the results for large field cases. We developed a novel, 3-dimensional chemical compositional and robust general reservoir simulator (UTGEL) to model gel treatment processes. The simulator has the capability to model different types of microgels, such as preformed particle gels (PPG), thermally active polymers (TAP), pH-sensitive microgels, and colloidal dispersion gels (CDG). The simulator has been validated for gel flooding using laboratory and field scale data. The simulator helps to design and optimize the flowing gel injection for conformance control processes in larger field cases. The gel rheology, adsorption, resistance factor and residual resistance factor with salinity effect, gel viscosity, gel kinetics, and swelling ratio were implemented in UTGEL. Several simulation case studies in fractured and heterogeneous reservoirs were performed to illustrate the effect of gel on production behavior and water control. Laboratory results of homogeneous and heterogeneous sandpacks, and Berea sandstone corefloods were used to validate the PPG transport models. Simulations of different heterogeneous field cases were performed and the results showed that PPG can improve the oil recovery by 5-10% OOIP compared to waterflood. For recovery from fractured reservoirs by waterflooding, injected water will flow easily through fractures and most part of reservoir oil will remain in matrix blocks unrecovered. Recovery from these reservoirs depends on matrix permeability, wettability, fracture intensity, temperature, pressure, and fluid properties. Chemical processes such as polymer flooding (P), surfactant/polymer (SP) flooding and alkali/surfactant/polymer (ASP) flooding are being used to enhance reservoir energy and increase the recovery. Chemical flooding has much broader range of applicability than in the past. These include high temperature reservoirs, formations with extreme salinity and hardness, naturally fractured carbonates, and sandstone reservoirs with heavy and viscous crude oils. The recovery from fractured carbonate reservoirs is frequently considered to be dominated by spontaneous imbibition. Therefore, any chemical process which can enhance the rate of imbibition has to be studied carefully. Wettability alteration using chemicals such as surfactant and alkali has been studied by many researchers in the past years and is recognized as one of the most effective recovery methods in fractured carbonate reservoirs. Injected surfactant will alter the wettability of matrix blocks from oil-wet to water-wet and also reduce the interfacial tension to ultra-low values and consequently more oil will be recovered by spontaneous co-current or counter-current imbibition depending on the dominant recovery mechanism. Accurate and reliable up-scaling of chemical enhanced oil recovery processes (CEOR) are among the most important issues in reservoir simulation. The important challenges in up-scaling CEOR processes are predictability of developed dimensionless numbers and also considering all the required mechanisms including wettability alteration and interfacial tension reduction. Thus, developing new dimensionless numbers with improved predictability at larger scales is of utmost importance in CEOR processes. There are some scaling groups developed in the past for either imbibition or coreflood experiments but none of them were predictive because all the physics related to chemical EOR processes (interfacial tension reduction and wettability alteration) were not included. Furthermore, most of commercial reservoir simulators do not have the capability to model imbibition tests due to lack of some physics, such as surfactant molecular diffusion. The modeling of imbibition cell tests can aid to understand the mechanisms behind wettability alteration and consequently aid in up-scaling the process. Also, modeling coreflood experiments for fractured vuggy carbonates is challenging. Different approaches of random permeability distribution and explicit fractures were used to model the experiments which demonstrate the validity and ranges of applicability of upscaled procedures, and also indicate the importance of viscous and capillary forces in larger scales. The simulation models were then used to predict the recovery response times for larger cores.
76

Geochemical and microbiological characterization of effluent and pore water from low-sulfide content waste rock

Bailey, Brenda Lee 15 April 2013 (has links)
Laboratory and field studies were completed to characterize the geochemistry and microbiology of drainage emanating from low-S content waste-rock test piles at the Diavik Diamond Mine (Diavik) from 2007 through 2010. The potential use of small-scale laboratory humidity-cell experiments to predict the water quality from larger-scale field-based experiments also was examined. Waste rock at Diavik is segregated into three categories according to sulfide content: Type I (target concentration: < 0.04 wt. % S), Type II (target concentration: 0.04 to 0.08 wt. % S) and Type III (target concentration: > 0.08 wt. % S). Four high-density polyethylene tanks, 2 m in diameter by 2 m in height, were filled with and surrounded by waste rock (active zone lysimeters; AZLs) at the Diavik site to study the upper 2 m of the active zone within a waste-rock pile and to evaluate the quality of effluent released from waste rock with differing S contents (Type I AZLs: 0.014 wt. % S and Type III AZLs: 0.035 wt. % S). In addition, three waste-rock test piles also were constructed at Diavik, two uncovered test piles (Type I test pile: 0.035 wt. % S and Type III test pile: 0.053 wt. % S) and a third pile was constructed based on the mine-closure plan which consists of waste rock (Type III: 0.082 wt. % S) capped with a 1.5 m layer of till and a 3 m layer of Type I material (Covered test pile). Each test pile is underlain by a high-density polyethylene geomembrane that captures and directs water to outflow drains. Results show that the release and transport of blasting residuals could be used as a resident tracer, indicating the first flush of water through the AZLs and the test piles. Variations in concentrations of blasting residuals and the gradual rate of dissipation provide an indication of the heterogeneity of the distribution of blasting residuals and the relative contributions of water and solutes from different flow paths. As temperatures within the test piles increase in response to ambient air temperature increases, larger proportions of the test pile contributed to the outflow, and increased concentrations of blasting residuals were observed in waste-rock test pile effluent. Effluent from the Type I AZLs and test pile maintained near-neutral pH (ranged from 5.8 to 8) with concentrations of SO₄²⁻ < 500 mg L⁻¹. These results suggest that the near-neutral pH values were associated with the presence of carbonates in the waste rock and the lack of intense acid generation. As ambient air temperatures increased in spring and summer of each year, the measured pH in the Type III test-pile drainage decreased from near-neutral in May (pH 7.5) to acidic conditions by October (ranged from 5 to 4.5). As the pH in the Type III test pile decreased, concentrations of SO₄²⁻ and dissolved metals increased (e.g. SO₄²⁻ > 1500 mg L⁻¹) suggesting sulfide oxidation was occurring. Maximum concentrations of SO₄²⁻, Al, Zn, Ni, Co, and Cu were observed in 2009 during the first flush of water through the Type III test pile. A sequence of acid-neutralization reactions was inferred based on the water chemistry of the effluent derived from the Type III AZLs and waste-rock test pile. This acid-neutralization sequence is similar to those observed at other AMD impacted sites. A series of mineral dissolution-precipitation reactions controlled pH and metal mobility; carbonate-mineral dissolution consumed H⁺ generated from sulfide-mineral oxidation at near neutral pH and the dissolution of Al and Fe (oxy)hydroxides consumed H⁺ at pH < 5.0. The cover system on the Covered test pile dampened the effects of ambient air temperature on the internal temperatures within the core of the Covered test pile. As a result, the Covered test pile had a relatively steady change in flow rate, with decreased flow from June to August, which led to a slow but prolonged release of sulfide-mineral oxidation products, such as SO₄²⁻ and dissolved metals, including Ni, Co, Zn, Cd, and Cu, compared to the uncovered Type III test pile. The pH decreased in 2008 and remained low for the duration of the study, whereas the pH in the uncovered test pile was near-neutral at the beginning of each field season in May and decreased to < 4.2 by the end of the field season in November. The microbiological-community profiles observed in the AZLs and waste-rock test piles suggest typical AMD-related species were present in acidic effluent with elevated concentrations of metals, whereas typical soil microbes were present in effluent with a near-neutral pH and lower concentrations of SO₄²⁻ and dissolved metals. The Type III AZLs, Type III test pile, and Covered test pile maintained populations of acidophilic Fe-oxidizers, whereas, the Type I AZLs and Type I test pile maintained populations of neutrophilic S-oxidizers. Laboratory humidity-cell (1 kg) results were scaled up to estimate the water quality from the Type III AZLs (6 t) using measured physical and chemical parameters. The results suggested over-prediction of SO₄²⁻ and metal concentrations when low mean annual precipitation occurred, limiting flushing of predicted oxidation products. In subsequent years with higher mean annual precipitation oxidation products from previous years were liberated and resulted in the under prediction of SO₄²⁻ and metal concentrations. Additionally, Fe and Al were over-predicted because Fe and Al concentrations in the AZL effluent may be controlled by the solubility and formation of secondary minerals, such as Fe oxyhydroxides, jarosite, and goethite, which were not included in the scaling procedure.
77

Geochemical and microbiological characterization of effluent and pore water from low-sulfide content waste rock

Bailey, Brenda Lee 15 April 2013 (has links)
Laboratory and field studies were completed to characterize the geochemistry and microbiology of drainage emanating from low-S content waste-rock test piles at the Diavik Diamond Mine (Diavik) from 2007 through 2010. The potential use of small-scale laboratory humidity-cell experiments to predict the water quality from larger-scale field-based experiments also was examined. Waste rock at Diavik is segregated into three categories according to sulfide content: Type I (target concentration: < 0.04 wt. % S), Type II (target concentration: 0.04 to 0.08 wt. % S) and Type III (target concentration: > 0.08 wt. % S). Four high-density polyethylene tanks, 2 m in diameter by 2 m in height, were filled with and surrounded by waste rock (active zone lysimeters; AZLs) at the Diavik site to study the upper 2 m of the active zone within a waste-rock pile and to evaluate the quality of effluent released from waste rock with differing S contents (Type I AZLs: 0.014 wt. % S and Type III AZLs: 0.035 wt. % S). In addition, three waste-rock test piles also were constructed at Diavik, two uncovered test piles (Type I test pile: 0.035 wt. % S and Type III test pile: 0.053 wt. % S) and a third pile was constructed based on the mine-closure plan which consists of waste rock (Type III: 0.082 wt. % S) capped with a 1.5 m layer of till and a 3 m layer of Type I material (Covered test pile). Each test pile is underlain by a high-density polyethylene geomembrane that captures and directs water to outflow drains. Results show that the release and transport of blasting residuals could be used as a resident tracer, indicating the first flush of water through the AZLs and the test piles. Variations in concentrations of blasting residuals and the gradual rate of dissipation provide an indication of the heterogeneity of the distribution of blasting residuals and the relative contributions of water and solutes from different flow paths. As temperatures within the test piles increase in response to ambient air temperature increases, larger proportions of the test pile contributed to the outflow, and increased concentrations of blasting residuals were observed in waste-rock test pile effluent. Effluent from the Type I AZLs and test pile maintained near-neutral pH (ranged from 5.8 to 8) with concentrations of SO₄²⁻ < 500 mg L⁻¹. These results suggest that the near-neutral pH values were associated with the presence of carbonates in the waste rock and the lack of intense acid generation. As ambient air temperatures increased in spring and summer of each year, the measured pH in the Type III test-pile drainage decreased from near-neutral in May (pH 7.5) to acidic conditions by October (ranged from 5 to 4.5). As the pH in the Type III test pile decreased, concentrations of SO₄²⁻ and dissolved metals increased (e.g. SO₄²⁻ > 1500 mg L⁻¹) suggesting sulfide oxidation was occurring. Maximum concentrations of SO₄²⁻, Al, Zn, Ni, Co, and Cu were observed in 2009 during the first flush of water through the Type III test pile. A sequence of acid-neutralization reactions was inferred based on the water chemistry of the effluent derived from the Type III AZLs and waste-rock test pile. This acid-neutralization sequence is similar to those observed at other AMD impacted sites. A series of mineral dissolution-precipitation reactions controlled pH and metal mobility; carbonate-mineral dissolution consumed H⁺ generated from sulfide-mineral oxidation at near neutral pH and the dissolution of Al and Fe (oxy)hydroxides consumed H⁺ at pH < 5.0. The cover system on the Covered test pile dampened the effects of ambient air temperature on the internal temperatures within the core of the Covered test pile. As a result, the Covered test pile had a relatively steady change in flow rate, with decreased flow from June to August, which led to a slow but prolonged release of sulfide-mineral oxidation products, such as SO₄²⁻ and dissolved metals, including Ni, Co, Zn, Cd, and Cu, compared to the uncovered Type III test pile. The pH decreased in 2008 and remained low for the duration of the study, whereas the pH in the uncovered test pile was near-neutral at the beginning of each field season in May and decreased to < 4.2 by the end of the field season in November. The microbiological-community profiles observed in the AZLs and waste-rock test piles suggest typical AMD-related species were present in acidic effluent with elevated concentrations of metals, whereas typical soil microbes were present in effluent with a near-neutral pH and lower concentrations of SO₄²⁻ and dissolved metals. The Type III AZLs, Type III test pile, and Covered test pile maintained populations of acidophilic Fe-oxidizers, whereas, the Type I AZLs and Type I test pile maintained populations of neutrophilic S-oxidizers. Laboratory humidity-cell (1 kg) results were scaled up to estimate the water quality from the Type III AZLs (6 t) using measured physical and chemical parameters. The results suggested over-prediction of SO₄²⁻ and metal concentrations when low mean annual precipitation occurred, limiting flushing of predicted oxidation products. In subsequent years with higher mean annual precipitation oxidation products from previous years were liberated and resulted in the under prediction of SO₄²⁻ and metal concentrations. Additionally, Fe and Al were over-predicted because Fe and Al concentrations in the AZL effluent may be controlled by the solubility and formation of secondary minerals, such as Fe oxyhydroxides, jarosite, and goethite, which were not included in the scaling procedure.
78

Optimisation and scale-up of a biotechnological process for production of L(+)-Lactic Acid form waste potato starch by Rhizopus arrhizus.

Zhang, Zhanying January 2008 (has links)
L(+)-Lactic acid is a commonly occurring organic acid, which is valuable due to its wide use in food and food-related industries, and its potential for the production of biodegradable and biocompatible polylactate polymers. The aim of this study was to optimize and scale-up a biotechnological process of L(+)-lactic acid production by suspended cells of R. arrhizus DAR 36017 with waste potato starch as the substrate. Commonly used inorganic and organic nitrogen sources, including ammonium sulphate, ammonium nitrate, urea, yeast extract and peptone, were assessed in conjunction with various ratios of carbon to nitrogen (C:N). Fermentation media with a low C:N ratio enhanced the production of lactic acid, biomass and ethanol, while a high C:N ratio led to production of more fumaric acid as a by-product. The use of organic nitrogen sources (yeast extract, peptone and urea) resulted in a significant reduction of lactic acid yields by 15% - 34% with a decrease of C:N from 168 to 28. The use of inorganic nitrogen sources (ammonium nitrate and ammonium sulphate) led to a high lactic acid yield of 84% - 91% at a C:N below 168. Therefore, ammonium nitrate and ammonium sulphate were considered to be better nitrogen sources for lactic acid production. Small pellets are the favoured morphological form for many fermentation processes by filamentous fungi. However, to control filamentous Rhizopus sp in the pellet form in a submerged fermentation system is difficult due to its filamentous characteristics. An acidadapted preculture technique was developed to induce the formation of the pellet form in bioreactors. Using the acid-adapted precultures, the fungal biomass can be controlled in small dispersed pellets as a dominant morphological form. With these small pellets, a lactic acid yield of 86-89%, corresponding to a concentration of 86-89g/L, was obtained in a laboratory scale process using a stirred tank reactor (STR) and a bubble column reactor (BCR). A batch bioprocess for lactic acid production was successfully scaled-up from shake flasks to laboratory scale bioreactors. Results from a simulated scale-up process revealed that the concentration and productivity of lactic acid decreased with the increase of the scale-up steps because of increased pellet size. This suggested that a one-step scale-up process using the acid-adapted preculture may be feasible in an industrial-scale bioreactor system. A comprehensive investigation of the impact of cultivation parameters on the morphology of R. arrhizus and lactic acid production was carried out in the BCR. The results showed that the fungal morphology was significantly influenced by carbon sources, pH, starch concentrations, sparger designs and aeration rates. The favoured morphology for lactic acid production was freely dispersed small pellets, which could be retained as a dominant morphology under operation conditions at pH 5.0 – 6.0, starch concentrations of 60 – 120 g/L and aeration rates of 0.2 – 0.8 vvm, using a sintered stainless steel disc sparger. The optimal cultivation conditions at pH 6.0 and aeration rate of 0.4 vvm resulted in the formation of the freely dispersed small pellets and production of 103.8 g/L lactic acid, with a yield of 87%, from 120 g/L liquefied potato starch in 48 h. This study shows a technically feasible and economically promising process for the production of lactic acid from waste potato starch. The use of waste potato starch instead of pure glucose or starch as substrate can significantly reduce the production cost, making this technology environmentally and economically attractive. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1339122 / Thesis (Ph.D.) -- University of Adelaide, School of Chemical Engineering, 2008
79

Alteração do processo de fabricação de comprimidos de diclofenaco sódico - foco na granulação úmida / Changing the manufacturing of diclofenac sodium tablets process - focus on wet granulation

Silveira, Larissa dos Santos da January 2014 (has links)
Made available in DSpace on 2016-06-21T13:45:02Z (GMT). No. of bitstreams: 2 9.pdf: 5002800 bytes, checksum: 1aab555cfe6db1a0cf1577ab298c8017 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2014 / Made available in DSpace on 2016-07-05T22:38:04Z (GMT). No. of bitstreams: 3 9.pdf.txt: 252589 bytes, checksum: b070d500ec1baafb988fc3fbf27085c1 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) 9.pdf: 5002800 bytes, checksum: 1aab555cfe6db1a0cf1577ab298c8017 (MD5) Previous issue date: 2014 / Fundação Oswaldo Cruz. Instituto de Tecnologia em Fármacos/Farmanguinhos. Rio de Janeiro, RJ, Brasil. / O escalonamento no processo de fabricação de comprimidos é um processo complexo e ainda bastante empírico, feito por método de tentativas e erros, cujos desafios são ainda maiores quando trata-se de formulação obtida por granulação úmida. Este trabalho realizou a transposição de escala de uma formulação de comprimidos revestidos contendo diclofenaco de sódio, fármaco de ação antiinflamatória,não esteroide e inibidor não seletivo das COX 1 e 2, avaliando os fatores relevantes para a obtenção tanto de uma formulação robusta, no que diz respeito ao processo de escalonamento em si, quanto de um medicamento que atendesse às exigências legais necessárias ao registro junto ao órgão regulador.Como resultado, o medicamento originário da formulação proposta apresentou-se aprovado em todos os ensaios exigidos, inclusive mostrando-se bioequivalente ao de referência. Este resultado ratificou a importância dos trabalhos preliminares,como a caracterização do ativo e os estudos referentes aos parâmetros a serem observados na transposição de escala. Na caracterização, as análises mostraram que a forma polimórfica do diclofenaco de sódio utilizado na formulação era a anidra,forma mais solúvel do fármaco; nas etapas de transposição de escala, identificou-se problemas com a alteração dos tempos de mistura do lote experimental para o lote piloto, pois não obteve-se uma boa compressibilidade para o lote piloto. Foi verificada, nas análises do granulado, uma diferença de granulometria que poderia justificar a diferença de desempenho entre os dois lotes. Um novo piloto foi manipulado, com a manutenção dos tempos de mistura do lote experimental, sendo que, dessa forma, os resultados satisfatórios do referido lote experimental foram reproduzidos para o segundo piloto, tanto em processabilidade quanto na avaliação granulométrica e demais ensaios. / Scaling up in the tabletting process is still a rather complex and empirical process carried out by trial and error methods, whose challenges are even greater when the formulation is obtained through wet granulation. Through this work, the development of large-scale production of a formulation of coated tablets containing diclofenac sodium, an anti-inflammatory drug, non-steroidal and non-selective inhibitor of COX 1 and 2, was conducted, evaluating the relevant factors for obtaining both a robust formulation with regard to the scale-up process itself and a drug which meets the legal requirements necessary for registration with the regulatory body. As a result, the product originating from the proposed formulation passed all of the required tests, and it was also proven to be bioequivalent to the reference drug. This result confirmed the importance of preliminary work, such as the characterization of active and studies concerning the parameters to be observed in the development of largescale production. In the characterization, the analysis showed that the polymorphic form of diclofenac sodium used in formulating was the anhydrous one, the more soluble form of the drug. In the steps of the development of large-scale production, there were problems with the alteration of the mixing times from the experimental batch to the pilot batch, as there was no good compressibility for the pilot batch. In the analyzes of the granulate, a difference of particle size was identified. It could explain the difference in performance between the two batches. Therefore, a new pilot batch was manipulated, with the maintenance of the mixing times of the experimental batch, and thus satisfactory results of the experimental batch were reproduced for the second pilot batch, regarding processability, particle assessment and other tests.
80

FinTech-startups i Stockholm : En kvalitativ studie om hur FinTech-startups arbetar för att skala upp verksamheten

Viinikka, Claudia, Svanberg, Pamela January 2018 (has links)
Dagens samhälle är digitaliserat och vi lever i ett paradigmskifte. Det sker en stor förändring inom finansmarknaden. Innovativa FinTech-startups tar över då traditionella finansinstitut inte klarar av att tillgodose kundernas ökade behov. Dessa FinTech-startups är viktiga och driver innovationen framåt i samhället och uppfyller kundernas allt högre krav. Dock har dessa företag svårigheter i att skala upp sin verksamhet vilket gör att de får svårigheter att överleva. Utmaningar de möter är främst inom finansiering och reglering. Syftet med studien är att undersöka hur FinTech-startups arbetar för att skala upp sin verksamhet samt hur de påverkas av och hanterar utmaningar i form av finansiering och reglering. Teorier som används är: FinTechs ekosystem, startups livscykel och teknologisk innovation. Studien är en kvalitativ undersökning med ett abduktivt angreppssätt och datainsamlingen har gjorts genom semistrukturerade intervjuer med personer från sex stycken Stockholmsbaserade FinTech-startups. Studiens resultatet visar att FinTech-startups möjligheter för att skala upp verksamheten till störst del är beroende av den finansiering som de får in. Dock upplever företagen svårigheter i att hitta investerare och hamnar i en ond cirkel. Tillstånd som krävs har en stor påverkan på företagens möjlighet att skala upp. / Digitizaliation charactarizes todays society and a new paragdim is a fact. There are considerable changes within the financial market where innovative FinTech-startups more and more take over the industry. This, due to that the traditional institutions cannot meet the costumers demands. The FinTech-startups are essential for the society and drives the innovation forward in order to fulfill the costumers requirements. However, these start-ups face difficulties with scaling-up which makes it hard for them to survive on the market. Financial funds and regulations are the main challanges they need to overcome. The purpose with this thesis is to examine how FinTech-startups work in order to scale-up their business and how they face challenges as financing and regulation. Theories used in this thesis are: FinTechs ecosystem, Startups life cycle and Technological innovation. A qualitative method is used with semistructured interviews with people from six different FinTech-startups based in Stockholm. The result of the studie shows that the FinTech-startups possibility to scale up mostly depends on financial funds. The companies experience challenges in finding investors and are placed in a vicious circle. In addition, conditions required have a major impact on the abilities to scale-up their business.

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