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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.
181

In Situ Polarization Modulation Infrared Reflection Absorption Spectroscopic and Kinetic Investigations of Heterogeneous Catalytic Reactions

Cai, Yun 14 January 2010 (has links)
A molecular-level understanding of a heterogeneous catalytic reaction is the key goal of heterogeneous catalysis. A surface science approach enables the realization of this goal. However, the working conditions (ultrahigh vacuum (UHV) conditions) of traditional surface science techniques restrict the investigations of heterogeneous catalysis system under industrial working conditions (atmospheric pressures). Polarization Modulation Infrared Reflection-Absorption Spectroscopy (PM-IRAS) can be operated in both UHV and atmospheric pressure conditions with a wide temperature span while providing high resolution (4 cm-1 is used in this dissertation) spectra. In this dissertation, PM-IRAS has been employed as a major technique to: 1) obtain both electronic and chemical information of catalysts from UHV to elevated pressure conditions; 2) explore reaction mechanisms by in situ monitoring surface species with concurrent kinetic measurements. In this dissertation, NO adsorption and dissociation on Rh(111) have been studied. Our PM-IRAS spectra show a transition of NO adsorption on three-fold hollow sites to atop sites occurs at low temperatures (<275 K). NO dissociation is found to account for this transition. The results indicated the dissociation of NO occurs well below the temperature previously reported. Characterizations of highly catalytically active Au films have also been carried out. Electronic and chemical properties of (1 x 1)- and (1 x 3)-Au/TiOx/Mo(112) films are investigated by PM-IRAS using CO as a probe molecule. The Au overlayers are found to be electron-rich and to have significantly different electronic properties compared with bulk Au. The exceptionally high catalytic activity of the Au bilayer structure is related to its unique electronic properties. CO oxidation reactions on Rh, Pd, and Pt single crystals are explored from low CO pressures under steady-state conditions (less than 1 x 10-4 Torr) to high pressures (0.01-10 Torr) at various gaseous reactant compositions. Surface CO species are probed with in situ PM-IRAS to elucidate the surface phases under reaction conditions. These experimental results are used to correlate reaction kinetics and surface reactant species. It is evident that there is a continuum over the pressure range studied with respect to the reaction mechanism. The most active phase has been shown to be an oxygen-dominant surface. The formation of a subsurface oxygen layer is found to deactivate the reaction.
182

Corrosion des aciers revetus de zinc dans les zones confinées des carrosseries automobiles

Lefevre, Bruno 06 1900 (has links) (PDF)
La corrosion automobile peut être classée en deux catégories: la corrosion cosmétique et la corrosion perforante. La corrosion cosmétique touche à l'aspect extérieur du véhicule, tandis que la corrosion perforante se produit lorsque de l'eau pénètre dans les corps creux du véhicule. Ce type de corrosion est particulièrement pernicieux puisqu'il aboutit à la perforation des tôles. L'objectif de ce travail est de comprendre les mécanismes régissant la corrosion perforante. Une cellule de corrosion a été développée afin de reproduire en laboratoire les conditions d'apparition de ce type de corrosion et permettre des mesures locales de pH dans un accostage. Le séchage des accostages et le développement de la corrosion ont été suivis par vidéo dans une enceinte climatique, les surfaces ont été caractérisées par XPS, IRRAS et MEB. Une enceinte couplée à un spectromètre PM-IRRAS a été développée pour suivre in situ la cinétique d'apparition des produits de corrosion du zinc en milieu humide.
183

Styrning av stegmotor för robot med NICompactRIO

Augustsson, Joacim, Larsson, Gustaf January 2009 (has links)
<p>Arbetet handlar om styrning och reglering av stegmotorer och permanentmagnetmotorer, genom attanvända det grafiska programmeringsspråket Labview från National Instruments (NI) tillsammansmed hårdvara i form av NI CompactRIO och NI USB datainsamlingskort. Implementeringen har sketti form av en robot med ett för uppgiften specialbyggt styrsystem, PWM – styrning av enpermanentmagnetmotor och en egenkonstruerad manöverdosa.</p> / <p>This report deals about controlling and regulating stepping motors and PM-motors by using thegraphical programming language NI Labview, with hardware NI CompactRIO and NI DAQ-USB.The implementation has been done by controlling a robot with a for the task built system, controllinga PM-motor by PWM and a own created controller.</p>
184

Klaipėdos miesto šiaurinės dalies oro taršos tyrimai ir modeliavimas / Investigation and modeling of the ambient pollution in Klaipeda city northern part

Petrauskas, Linas 21 June 2006 (has links)
Particulate matters – affected air pollution and air pollution sources in the Northern part of Klaipeda are being analysed in the final work. The first part of the work focuses on the air pollution in Lithuania and worldwide, leteron methods and devices for measuring the concentration of the particulate matters in the air are being analysed. Earlier research works on this subject are being analysed together with various information sources. With the help of modern efficient air polution measurement devices, particulate matters – affected air pollution and air pollution causes in the Northern part of Klaipeda were examined. After collecting data on transport concentration in certain streets of the seaport, it was possible to do the modelling of segments of these streets. the resuls of the modelling are being compared with the results of the pre-existing research. The conclusions and recommendations of the final work are based on the analyses of the particulate matters – affected air pollution and itas spread in Klaipeda. the work consists of 8 parts; the Introduction, the Literature overview, the analyses of the air pollution estimation methods and devices, Particulate matters – affected air pollution analyses in Klaipeda city, the modelling of the particulate matters spread in the seaport, Conclusions, Suggestions and References. The volume of work is 119 p., excluding appendices, 56 illustrations, 17 Figures, 58 reference sources. Articles for publication and publications... [to full text]
185

Airborne Particles in Indoor Residential Environment: Source Contribution, Characteristics, Concentration, and Time Variability

He, Congrong January 2005 (has links)
The understanding of human exposure to indoor particles of all sizes is important to enable exposure control and reduction, but especially for smaller particles since the smaller particles have a higher probability of penetration into the deeper parts of the respiratory tract and also contain higher levels of trace elements and toxins. Due to the limited understanding of the relationship between particle size and the health effects they cause, as well as instrument limitations, the available information on submicrometer (d < 1.0 µm) particles indoors, both in terms of mass and number concentrations, is still relatively limited. This PhD project was conducted as part of the South-East Queensland Air Quality program and Queensland Housing Study aimed at providing a better understanding of ambient particle concentrations within the indoor environment with a focus on exposure assessment and control. This PhD project was designed to investigate comprehensively the sources and sinks of indoor aerosol particles and the relationship between indoor and outdoor aerosol particles, particle and gaseous pollutant, as well as the association between indoor air pollutants and house characteristics by using, analysing and interpreting existing experimental data which were collected before this project commenced, as well as data from additional experiments which were designed and conducted for the purpose of this project. The focus of this research was on submicrometer particles with a diameter between 0.007 - 0.808 µm. The main outcome of this project may be summarised as following: * A comprehensive review of particle concentration levels and size distributions characteristics in the residential and non-industrial workplace environments was conducted. This review included only those studies in which more general trends were investigated, or could be concluded based on information provided in the papers. This review included four parts: 1) outdoor particles and their effect on indoor environments; 2) the relationship between indoor and outdoor concentration levels in the absence of indoor sources for naturally ventilated buildings; 3) indoor sources of particles: contribution to indoor concentration levels and the effect on I/O ratios for naturally ventilated buildings; and 4) indoor/outdoor relationship in mechanically ventilated buildings. * The relationship between indoor and outdoor airborne particles was investigated for sixteen residential houses in Brisbane, Australia, in the absence of operating indoor sources. Comparison of the ratios of indoor to outdoor particle concentrations revealed that while temporary values of the ratio vary in a broad range from 0.2 to 2.5 for both lower and higher ventilation conditions, average values of the ratios were very close to one regardless of ventilation conditions and of particle size range. The ratios were in the range from 0.78 to 1.07 for submicrometer particles, from 0.95 to 1.0 for supermicrometer particles and from 1.01 to 1.08 for PM2.5 fraction. Comparison of the time series of indoor to outdoor particle concentrations showed a clear positive relationship existing for many houses under normal ventilation conditions (estimated to be about and above 2 h-1), but not under minimum ventilation conditions (estimated to be about and below 1 h-1). These results suggest that for normal ventilation conditions and in the absence of operating indoor sources, outdoor particle concentrations could be used to predict instantaneous indoor particle concentrations but not for minium ventilation, unless air exchange rate is known, thus allowing for estimation of the "delay constant". * Diurnal variation of indoor submicrometer particle number and particle mass (approximation of PM2.5) concentrations was investigated in fifteen of the houses. The results show that there were clear diurnal variations in both particle number and approximation of PM2.5 concentrations, for all the investigated houses. The pattern of diurnal variations varied from house to house, however, there was always a close relationship between the concentration and human indoor activities. The average number and mass concentrations during indoor activities were (18.2±3.9)×10³ particles cm-³ and (15.5±7.9) µg m-³ respectively, and under non-activity conditions, (12.4±2.7)x10³ particles cm-³ (11.1±2.6) µg m-³, respectively. In general, there was a poor correlation between mass and number concentrations and the correlation coefficients were highly variable from day to day and from house to house. This implies that conclusions cannot be drawn about either one of the number or mass concentration characteristics of indoor particles, based on measurement of the other. The study also showed that it is unlikely that particle concentrations indoors could be represented by measurements conducted at a fixed monitoring station due to the large impact of indoor and local sources. * Emission characteristics of indoor particle sources in fourteen residential houses were quantified. In addition, characterizations of particles resulting from cooking conducted in an identical way in all the houses were measured. All the events of elevated particle concentrations were linked to indoor activities using house occupants diary entries, and catalogued into 21 different types of indoor activities. This enabled quantification of the effect of indoor sources on indoor particle concentrations as well as quantification of emission rates from the sources. For example, the study found that frying, grilling, stove use, toasting, cooking pizza, smoking, candle vaporizing eucalyptus oil and fan heater use, could elevate the indoor submicrometer particle number concentration levels by more than 5 times, while PM2.5 concentrations could be up to 3, 30 and 90 times higher than the background levels during smoking, frying and grilling, respectively. * Indoor particle deposition rates of size classified particles in the size range from 0.015 to 6 µm were quantified. Particle size distribution resulting from cooking, repeated under two different ventilation conditions in 14 houses, as well as changes to particle size distribution as a function of time, were measured using a scanning mobility particle sizer (SMPS), an aerodynamic particle sizer (APS), and a DustTrak. Deposition rates were determined by regression fitting of the measured size-resolved particle number and PM2.5 concentration decay curves, and accounting for air exchange rate. The measured deposition rates were shown to be particle size dependent and they varied from house to house. The lowest deposition rates were found for particles in the size range from 0.2 to 0.3 µm for both minimum (air exchange rate: 0.61±0.45 h-1) and normal (air exchange rate: 3.00±1.23 h-1) ventilation conditions. The results of statistical analysis indicated that ventilation condition (measured in terms of air exchange rate) was an important factor affecting deposition rates for particles in the size range from 0.08 to 1.0 µm, but not for particles smaller than 0.08 µm or larger than 1.0 µm. Particle coagulation was assessed to be negligible compared to the two other processes of removal: ventilation and deposition. This study of particle deposition rates, the largest conducted so far in terms of the number of residential houses investigated, demonstrated trends in deposition rates comparable with studies previously reported, usually for significantly smaller samples of houses (often only one). However, the results compare better with studies which, similarly to this study, investigated cooking as a source of particles (particle sources investigated in other studies included general activity, cleaning, artificial particles, etc). * Residential indoor and outdoor 48 h average levels of nitrogen dioxide (NO2), 48h indoor submicrometer particle number concentration and the approximation of PM2.5 concentrations were measured simultaneously for fourteen houses. Statistical analyses of the correlation between indoor and outdoor pollutants (NO2 and particles) and the association between house characteristics and indoor pollutants were conducted. The average indoor and outdoor NO2 levels were 13.8 ± 6.3 ppb and 16.7 ± 4.2 ppb, respectively. The indoor/outdoor NO2 concentration ratio ranged from 0.4 to 2.3, with a median value of 0.82. Despite statistically significant correlations between outdoor and fixed site NO2 monitoring station concentrations (p = 0.014, p = 0.008), there was no significant correlation between either indoor and outdoor NO2 concentrations (p = 0.428), or between indoor and fixed site NO2 monitoring station concentrations (p = 0.252, p = 0.465,). However, there was a significant correlation between indoor NO2 concentration and indoor submicrometer aerosol particle number concentrations (p = 0.001), as well as between indoor PM2.5 and outdoor NO2 (p = 0.004). These results imply that the outdoor or fixed site monitoring concentration alone is a poor predictor of indoor NO2 concentration. * Analysis of variance indicated that there was no significant association between indoor PM2.5 and any of the house characteristics investigated (p > 0.05). However, associations between indoor submicrometer particle number concentration and some house characteristics (stove type, water heater type, number of cars and condition of paintwork) were significant at the 5% level. Associations between indoor NO2 and some house characteristics (house age, stove type, heating system, water heater type and floor type) were also significant (p < 0.05). The results of these analyses thus strongly suggest that the gas stove, gas heating system and gas water heater system are main indoor sources of indoor submicrometer particle and NO2 concentrations in the studied residential houses. The significant contributions of this PhD project to the knowledge of indoor particle included: 1) improving an understanding of indoor particles behaviour in residential houses, especially for submicrometer particle; 2) improving an understanding of indoor particle source and indoor particle sink characteristics, as well as their effects on indoor particle concentration levels in residential houses; 3) improving an understanding of the relationship between indoor and outdoor particles, the relationship between particle mass and particle number, correlation between indoor NO2 and indoor particles, as well as association between indoor particle, NO2 and house characteristics.
186

Analysis and modelling of jitter and phase noise in electronic systems : phase noise in RF amplifiers and jitter in timing recovery circuits

Tomlin, Toby-Daniel January 2004 (has links)
Timing jitter and phase noise are important design considerations in most electronic systems, particularly communication systems. The desire for faster transmission speeds and higher levels of integration, combined with lower signal levels and denser circuit boards has placed greater emphasis on managing problems related to phase noise, timing jitter, and timing distribution. This thesis reports original work on phase noise modelling in electronic systems. A new model is proposed which predicts the up-conversion of baseband noise to the carrier frequency in RF amplifiers. The new model is validated by comparing the predicted phase noise performance to experimental measurements as it applies to a common emitter (CE), bipolar junction transistor (BJT) amplifier. The results show that the proposed model correctly predicts the measured phase noise, including the shaping of the noise about the carrier frequency, and the dependence of phase noise on the amplifier parameters. In addition, new work relating to timing transfer in digital communication systems is presented. A new clock recovery algorithm is proposed for decoding timing information encoded using the synchronous residual time-stamp (SRTS) method. Again, theoretical analysis is verified by comparison with an experimental implementation. The results show that the new algorithm correctly recovers the source clock at the destination, and satisfies the jitter specification set out by the ITU-T for G.702 signals.
187

VM allocation in cloud datacenters based on the multi-agent system : an investigation into the design and response time analysis of a multi-agent-based virtual machine (VM) allocation/placement policy in cloud datacenters

Al-ou'n, Ashraf M. S. January 2017 (has links)
Recent years have witnessed a surge in demand for infrastructure and services to cover high demands on processing big chunks of data and applications resulting in a mega Cloud Datacenter. A datacenter is of high complexity with increasing difficulties to identify, allocate efficiently and fast an appropriate host for the requested virtual machine (VM). Establishing a good awareness of all datacenter’s resources enables the allocation “placement” policies to make the best decision in reducing the time that is needed to allocate and create the VM(s) at the appropriate host(s). However, current algorithms and policies of placement “allocation” do not focus efficiently on awareness of the resources of the datacenter, and moreover, they are based on conventional static techniques. Which are adversely impacting on the allocation progress of the policies. This thesis proposes a new Agent-based allocation/placement policy that employs some of the Multi-Agent system features to get a good awareness of Cloud Datacenter resources and also provide an efficient allocation decision for the requested VMs. Specifically, (a) The Multi-Agent concept is used as a part of the placement policy (b) A Contract Net Protocol is devised to establish good awareness and (c) A verification process is developed to fully dimensional VM specifications during allocation. These new results show a reduction in response time of VM allocation and the usage improvement of occupied resources. The proposed Agent-based policy was implemented using the CloudSim toolkit and consequently was compared, based on a series of typical numerical experiments, with the toolkit’s default policy. The comparative study was carried out in terms of the time duration of VM allocation and other aspects such as the number of available VM types and the amount of occupied resources. Moreover, a two-stage comparative study was introduced through this thesis. Firstly, the proposed policy is compared with four state of the art algorithms, namely the Random algorithm and three one-dimensional Bin-Packing algorithms. Secondly, the three Bin-Packing algorithms were enhanced to have a two-dimensional verification structure and were compared against the proposed new algorithm of the Agent-based policy. Following a rigorous comparative study, it was shown that, through the typical numerical experiments of all stages, the proposed new Agent-based policy had superior performance in terms of the allocation times. Finally, avenues arising from this thesis are included.
188

Operational management through key performance Indicators : A case study performed at the warehouses at Fresenius Kabi

Salin Gustafsson, Martin, Frost, Carl January 2018 (has links)
Purpose: The purpose of this study is to identify and develop relevant keyperformance indicators within the warehouse operations in amanufacturing company, and how they can be used for control. Research question: In a manufacturing company, which are the most important KPIs forcontrolling and monitoring the warehouse operations, and how can thoseKPIs be developed?Methodology: This master thesis is based on a case study at a pharmaceutical companynamed Fresenius Kabi. A qualitative approach has been used whereprimary data was collected through 10 structured &amp; semi structuredinterviews and through observations in the warehouses to understand thecurrent state. Secondary data was used in form of academic papers to seewhat previous research had to say about KPIs and operation &amp; processmanagement. Internal documents were also used as a secondary source. Findings: Two key performance indicators have been developed, productivity andcost efficiency. A template has been designed to produce the KPIs. Thisstudy contributes to the understanding of how to develop KPIs that fits amanufacturing company´s warehouse operations and a recommendation onhow you could develop a system for producing the data.
189

Développement d'un capteur de suies pour application automobile - Etude des paramètres clés affectant sa réponse / Development of a soot sensor for automotive applications - Study of key parameters affecting his response

Grondin, Didier 19 April 2017 (has links)
Le transport routier est responsable d’une part des émissions de particules fines, notamment dans les grandes agglomérations. Celles-ci ayant des répercussions graves sur la santé humaine et l’environnement, des normes d’émissions des véhicules de plus en plus strictes sont mises en place. Des limites en nombre de particules sont imposées et une obligation de connaitre l’état de santé des organes de post-traitement des gaz d’échappement est également entrée en vigueur (On-Board Diagnostic : OBD).Les capteurs résistifs ont montré de bons résultats pour la mesure de la concentration massique des particules et ont l’avantage d’être simples à mettre en oeuvre, robustes et peu onéreux. Le principe de fonctionnement du capteur est basé sur la mesure de la conductance entre des électrodes de platine. Celle-ci augmente avec le dépôt de suies.L’objectif de ce travail de thèse est de parvenir à déterminer les paramètres clés qui affectent la réponse du capteur. Trois flux de suies présentant des distributions en taille différentes ont été sélectionnés et caractérisés. Un quatrième flux de suies a permis d’appréhender l’impact d’une concentration massique inférieure. La réponse du capteur à ces différents flux de suies a été étudiée. Nous avons montré que la sensibilité et le temps de réponse du capteur sont optimaux pour une tension de polarisation donnée entre les deux électrodes dont la valeur dépend de la distribution en taille des suies. Ce phénomène a été expliqué par les propriétés électriques différentes des suies et modélisé par un équilibre entre accumulation et combustion par effet Joule des suies déposées permettant de simuler la réponse temporelle du capteur. / Road transport contributes to a part of the particulate matter emissions, especially in big cities. Due to the negative effect of these pollutants on the human health and environment, more and more stringent emission standards for automotive are applied. These emissions are now limited in number of particles per kilometer and the vehicle need to indicate when there is some failure of the systems of depollution (OBD: On-Board diagnostic).Resistive sensors have shown good results to measure soot particles mass concentration. They have advantage of being a simple and robust technology that can be easily manufactured at a cheap price. The sensor principle consists of conductance measurement between two platinum electrodes. Conductance increases with soot deposition. This work aims to define the key parameters that affect the sensors response. Three particles flow with different particles size distributions (centered at 90, 70 and 50 nm) were used and characterized. A fourth flow was used to see the impact of a lower mass concentration. The sensor response exposed to these different flows was studied. It was shown that the sensor sensibility and response times are optimal for a given polarization voltage between the electrodes whose value depends on the size distribution. This phenomenon was explained by the different electrical properties of the soot particles and modeled by equilibrium of soot accumulation and their combustion by Joule heating that permitting to simulate the sensor temporal response.
190

Interação entre modelos de membrana biológica e poluentes emergentes / Interaction between biological membrane models and emerging pollutants

Maximino, Mateus Dassie [UNESP] 23 February 2018 (has links)
Submitted by Mateus Dassie Maximino (mateusmaximino23@gmail.com) on 2018-04-23T13:55:51Z No. of bitstreams: 1 Dissertação Mestrado - Mateus Dassie Maximino.pdf: 5933036 bytes, checksum: 96040f746ca01578e5036f01f3d89e6e (MD5) / Approved for entry into archive by Claudia Adriana Spindola null (claudia@fct.unesp.br) on 2018-04-23T14:37:07Z (GMT) No. of bitstreams: 1 maximino_md_me_prud.pdf: 5933036 bytes, checksum: 96040f746ca01578e5036f01f3d89e6e (MD5) / Made available in DSpace on 2018-04-23T14:37:07Z (GMT). No. of bitstreams: 1 maximino_md_me_prud.pdf: 5933036 bytes, checksum: 96040f746ca01578e5036f01f3d89e6e (MD5) Previous issue date: 2018-02-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho trata do estudo da interação entre os poluentes emergentes amoxicilina (AMX) e azul de metileno (AM) com modelos-simples de membrana biológica compostas de fosfolipídios zwiteriônicos (DPPC e DOPC), através de filmes de Langmuir e vesículas unilamelares gigantes (GUVs). As membranas foram expostas aos poluentes de forma individual e também misturados (MIX) para que se aproximasse de uma situação real, neste caso, o chamado efeito coquetel, no qual os poluentes são encontrados misturados no ambiente. O objetivo principal foi investigar as possíveis interações entre os poluentes e os fosfolipídios e os consequentes efeitos nas membranas. Nos filmes de Langmuir, as isotermas π-A (pressão superficial por área molecular média) de DPPC revelaram que a AMX e o AM são expulsos da interface ar-água conforme a fase condensada é atingida. O DOPC demonstrou ser menos afetado pela AMX, uma vez que a isoterma não apresentou deslocamento. Contudo, o DOPC se mostrou mais susceptível a interagir com o AM, visto que um deslocamento significativo foi observado. Para ambos os lipídios a MIX causou maiores efeitos, evidenciados por deslocamentos maiores nas isotermas. Análises de módulo compressional mostraram um pequeno aumento na fluidez do filme de DPPC, não observado para o DOPC. As medidas de microscopia de ângulo de Brewster (BAM) na presença dos poluentes revelaram mudanças na morfologia dos filmes, afetando a formação dos domínios de DPPC e impedindo a formação dos mesmos nas monocamadas de DOPC. Os espectros de PMIRRAS para o DPPC indicaram possíveis interações eletrostáticas dos poluentes com a cabeça polar do lipídio, assim como uma desordem na região da sua cauda apolar. A monocamada de DOPC foi bastante afetada pois ocorreram mudanças nas vibrações de quase todos os grupos químicos do lipídio, apresentando inclusive mudanças na região da cauda do lipídio. Os espectros de emissão da sonda LAURDAN nas LUVs revelaram um aumento da rigidez para ambos os lipídios, diferentemente do observado pelas análises de elasticidade da monocamada de Langmuir. As GUVs para ambos os fosfolipídios, ao contrário das monocamadas, apresentaram maior efeito sobre os poluentes aplicados de forma individual, visto que para os poluentes avaliados individualmente foram observados a perda de contraste de fase para os lipídios na presença do AM, assim como mudanças na estabilidade para as GUVs de DOPC em AMX. Tais efeitos não foram observados para a MIX, devido as diferenças estruturais dos modelos de membrana. / The present work is about the interaction between the emerging pollutants amoxicillin (AMX) and methylene blue (MB), with biological membrane models of zwitterionic phospholipids (DPPC and DOPC), through Langmuir films and giant unilamellar vesicles (GUVs). The membrane was exposed to the presence of the pollutants individually, still being performed the analysis with the mixture (MIX) of both in order to get closer to a real situation, in which the pollutants are found mixed in the environment. The main goal was to investigate the possible interactions between the pollutants and phospholipids. The π-A (surface pressure by mean molecular area) isotherms of DPPC reveal that in the condensed phase the lipid expelled the AMX and MB of the air-water interface. The DOPC showed to be less affected by the AMX, once the isotherm did not present a displacement. However, the DOPC showed to be more susceptible to interact with the MB, since significant displacements were observed. In both lipids, the MIX showed to be more effective, causing bigger displacements. The analysis of compressional modulus showed a small increase of the fluidity of the DPPC film, which was not observed to the DOPC. The Brewster Angle Microscopy (BAM) measurements in the presence of the pollutants revealed changes in the morphology, affecting the domains formation of DPPC and inhibiting the formation of the same in monolayers. The PM-IRRAS specters to the DPPC indicated possible electrostatic interactions with the head, as well as a disorder in the tail. The DOPC monolayer was quite affected because there have been changes in almost all chemical groups of lipid, including changes in the tail region of the lipid. The emission spectrum from the dye LAURDAN in the LUVs revealed an increase in the rigidity for both lipids, different from the observed in the analysis of elasticity in the Langmuir monolayers. The GUVs for both phospholipids, unlike the monolayers, showed a major effect on the pollutants applied individually since that were observed losses of phase contrast for the lipids in the presence of MB, such as changes in the stability of the DOPC GUVs in AMX. Such effects were not observed in the MIX, due to the structural differences in the membrane models.

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