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Barrick, Andrew. "Ecotoxicological study of the impact of nanomaterials on marine mussels through a high throughput screening approach". Electronic Thesis or Diss., Nantes, 2018. http://www.theses.fr/2018NANT4042.
Pełny tekst źródłaNanotechnology is an emerging field that is considered the industrial revolution of the 21st century. In this context, Manufactured nanomaterials (MNMs) will inevitably be released into the aquatic environment. In the objective of MNM regulation, the aim is to implement a read-across (grouping) approach based on high throughput screening (HTS) techniques as a way of quickly prescreening many MNMs in a cost-effective manner. Regulation is also focused on developing safe(r)-by-design (SbD) concept to integrate safety into the production of products. In this sense, for this work, an HTS platform on Mytilus edulis hemocytes has been developed using endpoints for cell viability as well as gene expression. Industrial case studies were investigated in in vitro testing following the HTS approach. In parallel an in vivo approach was assessed to determine if both testing strategies would come to the same conclusions on which product was SbD. In addition, a wide array of MNMs were also tested for effects on cell viability to establish a relevant database to investigate a grouping approach for MNM. This work demonstrated the relevance of using an HTS platform for M. edulis hemocytes to prescreen MNMs for environmental risk. Gene expression also provides a promising framework for investigating modes actions for MNM toxicity as well as the potential to develop adverse outcome pathways for SbD. This thesis established a preliminary database for ecotoxicology that could be implemented in a regulatory approach for NMs
Dubascoux, Stéphane. "Développement d’une méthode de fractionnement par couplage flux force (FFF) multi détection pour la caractérisation de colloïdes naturels". Pau, 2007. http://www.theses.fr/2007PAUU3038.
Pełny tekst źródłaThe role of colloids is crucial in environmental processes. They can control the transport of chemical pollutants and play a major role in biogeochemical cycles. Despite colloids are known for a long time, they remain often neglected in environmental studies due to the lack of convenient analytical tools. This work concerns the development of analytical conditions for the analysis and the fractionation of two main natural colloid populations (nanoparticles and humic acids) by As-Fl-FFF (Asymmetrical Flow-Field Flow Fractionation). This fractionation tool is associated to several detectors as Ultraviolet/Visible and Multi-Angle Laser Light Scattering (MALLS). Monitoring and quantification of trace elements were also performed thanks to the hyphenation with an Inductively Coupled Plasma Mass Spectrometer (ICP-MS). Finally an original approach combining colloidal fractionation of a landfill leachate and chemical speciation of tin associated to its different colloidal fractions was realised. This new approach has shown the potentiality and the importance of colloidal consideration in environmental studies
Lansade, David. "Stabilisation de résines poly(diméthylsiloxane) en environnement spatial radiatif". Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0219.
Pełny tekst źródłaSatellites on orbit near Earth have to face a radiative environment, which strongly degrades materials that constitute them. In particular, in geostationary orbit, many electromagnetic radiations and particles shorten the lifespan of such materials. Poly(dimethylsiloxane) resins are used in large amounts on satellites as binders or insulators and are degraded by these radiations, which translates into a loss of transparency and the formation of cracks at their surface. The work presented herein aims at limiting the degradations suffered by the resins when they undergo simulated ageing, especially through proton irradiation. In a first approach, the embedding of a layer of silica nanoparticles assembled in a compact way at the surface of the resins was studied. The size of the nanoparticles, their diameter, as well as their covalent binding to the matrix were investigated. A second approach was to synthetize a poly(dimethylsiloxane) resin in which all or part of the crosslinking is achieved via a thermically reversible (retro-)Diels-Alder reaction
Eymard-, Vernain Elise. "Etude des interactions entre trois types de nanoparticules métalliques et une bactérie du sol, Bacillus subtilis". Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAV065/document.
Pełny tekst źródłaMetallic nanoparticles are used in variety of consumer products (solar screen, paint or medicine), which results in an increasing release of nanoparticles in the environment. There is a need of better evaluating their fate and impacts in the environment. Microorganisms are one of the first targets of nanoparticles in the environment. Most studies on microorganisms and bacteria have focused on cellular mortality, and did not take into account possible transformations of NPs in the environment, which modify their toxicity. This study is focused on model bacteria, Bacillus subtilis and three nanoparticles: Ag-NPs, ZnO-NPs and TiO2-NPs. We evaluate on one hand the impact of nanoparticles on the metabolism on the metabolism of Bacillus subtilis, and on the other hand the impact of Bacillus subtilis and of its secretome on the nanoparticles, both being mutually dependent
Plan, Anouchka. "Nanoparticules en environnement cellulaire : Impact de la nano-architecture sur l'internalisation, la biodégradation et les fonctionnalités thérapeutiques". Thesis, Sorbonne Paris Cité, 2019. http://www.theses.fr/2019USPCC033.
Pełny tekst źródłaInorganic nanoparticles represent innovative solution to face current limitations in early diagnostic or targeted therapies.First part focuses on the interactions between magnetic nanoparticles and stem cells to understand better the parameters which impact internalization and biodegradation. We evidenced an impact from the nanoparticle’s coating, the presence of proteins and the aggregation. Nanoparticles’ impact on cellular differentiation shown a process of re-magnetization of the iron products of degradation for some differentiation ways.In the second part, we studied anti-cancerous hyperthermal therapies and more precisely the impact of the intracellular confinement. We shown that the cellular environment can completely inhibit the heating delivered by magnetic hyperthermia but at the contrary can also be beneficial for applying photothermia at biocompatible wavelengths. Finally, the combination of photothermia with a drug leaded to an increase of the efficiency of both therapies separated with reduces secondary effects
Dzumedzey, Yuliya. "Mobility of manufactured nanoparticles within a natural organic gel". Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0159/document.
Pełny tekst źródłaThe mobility and fate of manufactured nanoparticles (NPs) in the environment drive the exposure behaviour. This study deals with the question on how NPs interact with environmental components, and how this interaction may alter the NPs fate and impact on the biota. We investigated the interaction of variably charged and sized NPs (TiO2 NPs, as analogues of those typically released from sunscreen, and Au NPs as models) with pure polysaccharide YAS34 as analogue of bacterial gels. The release of TiO2 NPs from a typical sunscreen under aqueous aging was first studied. The interaction between NPs and the bacterial polysaccharide was studied (1) in diluted suspension conditions, (2) by deposition on the gel surface as compared to a bare SiO2 mineral collector, and (3) by measuring the NPs transfer through the gel. Favorable and unfavorable conditions for NPs attachment to the polysaccharide were prepared by selecting appropriate pH and NPs coating.Under favorable conditions, the NPs tended to heteroaggregate with the EPS in suspension, leading to their partial sedimentation. On the EPS substrate, the NPs deposition was influenced by the physicochemical conditions. The NPs deposition is driven by electrostatic interactions with the collector and is also affected by the interactions between the neighbouring NPs. Surprisingly, under unfavourable conditions, some weak attractive interactions were again evidenced both in suspension and deposition experiments that we attributed to be dependent on the NP organic coating competing with the EPS.The NPs transfer through the gel was favored under repulsive electrostatic interaction, and affected by the NPs size and by the solution pH
Dedeh, Amina. "Impact d'un sédiment dopé aux nanoparticules d'or ou de sulfure de cadmium sur un invertébré et un poisson d'eau douce". Electronic Thesis or Diss., Bordeaux, 2014. http://www.theses.fr/2014BORD0068.
Pełny tekst źródłaThe aim of this thesis was to determine the impact of two types of metal nanoparticles (cadmium sulphide - CdS - and gold - Au) on two aquatic models (tubifex worms and zebrafish Danio rerio). The approach has been to dope the Garonne sediment with the two types of nanoparticles and characterize the effect of this contamination on the two animals using multiple markers at different levels of biological organization (biochemical responses, neurotransmission activity, genotoxicity, gene expression and bioturbation activity). The effects were evaluated after exposure to contaminated sediment in experimental microcosms systems for twenty days. In a number of cases this work revealed an effect of the nanoparticles that was not due to metal but to the nanoparticulate properties. Indeed, in the case of CdS nanoparticles, we observed alterations in the genome as well as the modification of the bioturbation activity of worms tubifex in response to the contamination of nanoparticles but not to that of the ionic form. In this work we observed the release of gold nanoparticles from the sediment into the water column, and its potential bioavailability to fish. These nanoparticles were causing DNA damage in both organisms, modifying the expression of certain genes and increased acetylcholinesterase activity in zebrafish. Bioturbation results showed no effects of gold nanoparticles on the movement of worms
Kebe, Seydina Ibrahima. "Synthèse de matériaux monolithiques pour la séparation et la catalyse en phase liquide : problématiques environnementales et du développement durable". Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1127/document.
Pełny tekst źródłaPolymeric materials have gained immense popularity with the golden age of petroleum and they still today meet with great success through Green polymer chemistry approaches and numerous high added value dedicated application in scientific domains such as analytical chemistry, medicine, space investigations, where one of the key for success is the design of miniaturized objects. In this contribution, micro-sized monolithic materials have been designed though either in microchannel immobilization (I.D. = 75 µm) or surface attachment on glass substrates (hundredths of microns in thickness). Polymers exhibiting monolithic morphology were considered to benefit of high permeability, mechanical and thermal resistances which are mandatory to flow chemistry applications. With the aim to control the interfacial interaction ability, a generic monolith having N-hydroxysuccinimide ester groups was used and on purpose functionalized. Molecular segments acting as selector – for electrochromatographic applications – of metal nanoparticles ligands – for supported catalysis applications – have been immobilized on the monolith surface via classical (nucleophilic substitution) or original (photo-induced thiol-ene click) grafting reactions.The so-designed materials were characterized through spectroscopic, microscopic, diffraction, thermogravimetric methods providing insight into correlation between the observed separation and catalytic abilities and the interfacial structure of the monolith. As representative examples of application, one may cite the electrochromatographic separation of toxic molecules such as organic pollutants (phenols, anilines, polycyclic aromatic hydrocarbons, polychlorobiphenyls), preservatives in cosmetics (parabens) and biomarkers (polycyclic aromatic hydrocarbons, pyrimidic bases). The analyses were conducted on model solutions and complex matrices (cosmetics, extraterrestrial analog samples). Flow catalytic reaction meant for the reduction of nitroarenes, the oxidation of aromatic alcohol, the carbon-carbon coupling and the sensitive detection of pesticides and synthesis intermediates (para-nitrophenol) have been achieved
Schulz, Aurélie. "Analyse de l'impact du cycle de vie des NPs TiO2 manufacturées à l'échelle du site spécifiqe : cas de la vallée de la Thur, 68, France". Electronic Thesis or Diss., Strasbourg, 2020. http://www.theses.fr/2020STRAH022.
Pełny tekst źródłaThe impact of engineered TiO2 NPs was assessed using the Life cycle assessment methodology at a site-specific scale. A first approach was carried out to detect them in the environment. Experimental data collected in the field were used to characterize these nanoparticles for terrestrial ecotoxicity at a local scale. TiO2 NPs were detected in the water and sediments of the Thur river and in soils of the study area up to 2,5 km from a production site. The residence time (fate factor) of TiO2 NPs in area soils of Thann is approximately 8500 years. A specific effect factor (12,46 PAF.m3.kg-1) was also developed using date from a bibliographic synthesis on the toxicity of TiO2 NPs for organisms in terrestrial ecosystem. The determination of these two parameters allows us to calculate the first characterization factor for TiO2 NPs for terrestrial ecotoxicity in the Thann region (1,06.105 PAF.m3.an.kg-1)
Larue, Camille. "Impact de nanoparticules de TiO2 et de nanotubes de carbone sur les végétaux". Phd thesis, AgroParisTech, 2011. http://pastel.archives-ouvertes.fr/pastel-00765312.
Pełny tekst źródłaLe, Bars Maureen. "Devenir du zinc des produits résiduaires organiques après méthanisation et recyclage agricole : rôle des nanoparticules de sulfure de zinc". Electronic Thesis or Diss., Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0034.
Pełny tekst źródłaAgricultural recycling of organic waste (OW), raw or after a treatment like anaerobic digestion (AD) and/or composting is common. It is necessary to assess the environmental impact of OW agricultural recycling after anaerobic digestion since this technology is gaining interest, particularly regarding zinc, an abundant element in OW. In order to properly evaluate the risk, zinc speciation must be known. First, we have shown that AD promote the formation of nano-ZnS that is therefore the main species of Zn (> 70%) in AD digestates. This unstable species is transformed during composting of 1 to 3 months. Size and strain are parameters that can explain nanocrystals reactivity. We showed that the more nano-ZnS are small and the higher the strain is. Interaction with thiol containing organic molecules, potentially present in anaerobic digesters, release nano-ZnS structural strain and control its growth. Finally, amended soil characteristics have a key role for nano-ZnS fate: the components of clayey and iron-oxide-rich soils are able to immobilize Zn released by nano-ZnS dissolution, unlike sandy soils components. This work gives a better understanding of zinc dynamics in cultivated ecosystems subject to spreading of organic waste
Déniel-Babin, Maureen. "Spectroscopies infrarouge et Raman de microalgues : étude des interactions avec des micro et nanoparticules". Thesis, Le Mans, 2020. http://www.theses.fr/2020LEMA1012.
Pełny tekst źródłaIn a context of contamination of natural waters by anthropogenic micro and nanoparticles (plastics, metals, oxides...), the study of their interactions with freshwater microalgae, the first link in the trophic chain, is essential. Techniques such as vibrational spectroscopies (Raman and infrared), which allow sensitive and rapid analysis without sample preparation, may be of interest. They have been tested here on the model microalga Chlamydomonas reinhardtii to quickly detect the effects of environmental stresses (light, drop of nutrients and presence of metals). Infrared spectroscopy proved to be a good tool, allowing rapid variation in biochemical composition to be monitored, helping to easily discriminate between the different stresses on the microalgae. This technique was then used to assess the impact of the presence of particulate pollutants (metallic and plastic nanoparticles in particular). The short- and medium-term impact of nanoparticles on freshwater microalgae was characterized in parallel with another known stress (nitrogen nutrient deficiency) in order to compare the different responses. The main results of exposure to nanoparticles show overall the immediate non-toxicity of nanoparticles at the tested concentrations. However, a loss of membrane integrity in contact with polystyrene nanoparticles suggests a stronger interaction of the microalgae studied with nanoplastics than with gold nanoparticles of similar size. Infrared spectra of C. reinhardtii showed a modification of protein and carbohydrate bands following environmental changes. In order to understand the variations observed at the level of carbohydrates, components of the microalgae structure and representing an important and complex part of the infrared spectrum, an in-depth study of this area was carried out by deconvolution of the infrared spectra. In order to better understand the response mechanisms involved, a study of the expression of genes (RT-QPCR) related to stress and carbohydrates production was carried out in parallel with infrared spectroscopy. The results thus obtained showed that polystyrene nanoparticle and C. reinhardtii interactions resulted in a genetic and macromolecular response at the carbohydrate level. Thus, the nanoparticle type effect was confirmed by the expression of the gene linked to the biosynthesis of galactose. Understanding the role of the cell-wall in the interaction with nanoparticles, particularly in case of polymers, was also studied by comparing two strains of C. reinhardtii (with and without cell-wall). Finally, microalgae response as a function of the interaction time with nanoparticles was investigated in order to try to understand whether, in the medium term, the responses presented a temporal variation. In addition, in order to better understand the effect of plastic particles at a higher trophic level, complementary work on the impact of microplastics on daphnia was carried out
Germande, Ophélie. "Impact environnemental et sanitaire des particules de nickel émises par les activités minières en Nouvelle Calédonie". Electronic Thesis or Diss., Bordeaux, 2022. http://www.theses.fr/2022BORD0282.
Pełny tekst źródłaBy producing about 158,000 tons of nickel (Ni) per year, New Caledonia is one of the largest producers of Ni in the world, with soils rich in trace metals (Ni; chromium, Cr; cobalt, Co; manganese, Mn and iron, Fe). This massive Ni exploitation is a major economic issue for the country (8 to 17% of annual GDP) to the detriment of potential environmental and health impacts. Indeed, the exploitation of these open-pit nickel laterite mines leads to the emission of ultrafine particles of Ni and nickel oxide (NiO) disseminated in the environment, by the wind, or via run-off from watercourses but also of other metals present in these soils. These particles can be inhaled by mine workers and the surrounding population, raising questions relating to human toxicology, and can also be transported along freshwater streams close to the mines, to be deposited or washed downstream as far as the lagoon, thus impacting aquatic organisms, the study of which is a matter of ecotoxicology.From an environmental point of view, few studies have been conducted in New Caledonia. However, initial work on freshwater rivers near mines has shown very high levels of Ni accumulated in organisms under the mining influence, particularly in Pacific eels. In order to document the significance of the toxic impacts potentially inflicted on eels present at these sites, different types of approaches have been conducted: (i) Analysis of the toxic impacts of metals on Anguilla marmorata collected in situ during a mission (morphometric measurements, metal levels in organs, transcriptomic); (ii) Impact of exposure to NiO nanoparticles (NPs) on eel hepatocytes in vitro, the liver being a prime target of metal toxicity and an essential organ for eels. These approaches made it possible to early identify the cellular and molecular mechanisms of cytotoxic impact, oxidative stress, inflammation and mitochondrial dysfunction following this exposure.In parallel, human exposure to NPs is a public health concern. NPs can thus cross the alveolar-capillary barrier, find their way into the general circulation and exert deleterious effects through direct interactions with the cardiovascular system and, in particular, the endothelial cells (HPAEC) lining the lumen of the vessels and controlling vascular reactivity, which is modified after Ni NPs exposure. These effects could thus be amplified in cardiovascular pathologies. People suffering from pathologies of the pulmonary circulation (pulmonary hypertension, PH) could therefore constitute populations at risk. Thus, it is necessary to better characterize, in exposed populations, the toxic mechanisms induced by Ni-rich dusts and by NiO NPs on the cardiovascular system. For this purpose, we studied, on HPAEC, the effects induced by NiO NPs on calcium signaling , the pro-inflammatory response and the role of oxidative stress in the observed modifications, as well as the impacts of these NPs in a pathological conditions by using an in vitro model mimicking the vascular dynamics observed during PH with the STREX® stretching system. Our results show that exposure to NiO NPs induces oxidative stress, a pro-inflammatory response as well as alterations in calcium homeostasis and that these effects are amplified when the cells are under pathological conditions. This work therefore suggests that exposure to NiO NPs could aggravate some pathophysiological events in patients suffering from pre-existing cardiovascular diseases such as PH, and that these patients would be more sensitive to these particulate pollutants
Al-Sid-Cheikh, Maya. "Impact des oxydes de fer naturels et des nanoparticules manufacturées sur la dynamique des éléments traces dans les sols de zones humides". Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S144.
Pełny tekst źródłaNanoscience is based on changes in particle properties when their diameter is below 100 nm (ie nanoparticles, NPs). Considering the increasing use of such NPs and their discharge into the environment, the assessment of their risks to human health and the environment is a major issue. Underneath the protection of waters and soils, the surface water assessment quality is particularly important, especially in wetlands, where the toxic metals dynamic (e.g. As, Pb, Ni, Cr , Hg) is complex and depends on the redox conditions of the environment. As magnetite (nano-Fe3O4), a natural or manufactured NP, is known for its significant adsorption capacity with heavy metals, their interactions in riparian wetlands with trace metals (TMs) remain critical concerning their direct of indirect impact on trace metals (TMs) mobility. The objective of this thesis was to study the role of manufactured nano-Fe3O4 (~ 10nm) and natural iron oxides on the TMs dynamics in wetland surface waters and soils. Therefore, in a first part considering natural colloidal precipitates from reoxidation products from riparian areas (subject to redox oscillations), a spatial distribution of elements was performed using nanoSIMS isotope mapping (i.e. 75As-, 56Fe16O-, sulfur (32S-) and organic matter (12C14N-), while the sulfur speciation was evaluated X-ray adsorption at K edge of the sulfur (S) (XANES). These analyzes allowed to highlight the interactions between natural iron oxides, natural organic matter (NOM) and a toxic metalloid, As. Our results suggest, with a statistical colocalization of nanoSIMS images, the existence of two interaction types: (1) 12C14N-, 32S-, 56Fe16O- and 75As-, and (2) 12C14N-, 32S- and 75As-. The coexistence of the oxidized and reduced forms of S, confirmed by the XANES analyses might be attributed to the slow oxidation kinetic of MON. Thus, this first part shows that in addition to the known interactions between MON, iron oxides and As, a possible direct interaction between As and NOM through sulfur functional groups (e.g. thiols) are also possible in oxidized environment. In a second part, the effect of nano-Fe3O4 (~ 10 nm) on trace elements (TEs) and colloids mobility in the organomineral horizon of a natural wetland soil was assessed using soil columns. Our results show that the nanoparticles coating influences the mobility of NOM and TMs. Indeed, the TMs mobility increases in presence of naked nano-Fe3O4, suggesting associations where NOM stabilizes the nanoparticles and increase the nanoparticles and associated TMs mobility. This mechanism seems less possible with coated nano-Fe3O4 where MON blocks the coating adsorption sites and therefore the adsorption of metals
Ivaneev, Aleksandr. "Utilisation complémentaire des techniques de fractionnement flux-force asymétrique et en colonne tournante pour la caractérisation d'échantillons environnementaux de particules". Electronic Thesis or Diss., Pau, 2020. http://www.theses.fr/2020PAUU3035.
Pełny tekst źródłaEnvironmental particles, especially nanoparticles (NPs), have a potential risk for human health and ecosystems due to their ubiquity, specific characteristics and properties (extremely high mobility in the environment, abilities of accumulation of toxic elements and penetration in living organisms) and, hence, should be scrutinized. The study of environmental NPs remains a challenge for analytical chemistry. In fact, NPs in a polydisperse environmental sample may represent only one thousandth or less of the bulk sample. Consequently, a considerable sample weight must be handled to separate amount of NP fraction sufficient for their dimensional and quantitative characterization. The group of field-flow fractionation (FFF) techniques can serve as a relevant basis for the development of methodology applicable to the study of environmental NPs.This doctoral thesis focuses on the use of asymmetrical flow and coiled tube field-flow fractionation techniques (A4F and CTFFF, respectively) in the investigation of environmental particulate samples. The results obtained demonstrate the advantages of these techniques applied to the study of volcanic ash nanoparticles. It should be highlighted that CTFFF technique has an increased separation capacity as compared to A4F, while A4F has an increased resolution. CTFFF was applied to the separation of NPs from environmental samples and a new coiled tube field-flow fractionation procedure was proposed. Dimensional and elemental characterization was carried out using A4F coupled to laser light scattering and ICP-MS. Furthermore, the results related to the investigation of stability of environmental nanoparticles are also given
Perrier, Fanny. "Nanocontamination d'organismes aquatiques par des particules inorganiques : transfert trophique et impacts toxiques". Electronic Thesis or Diss., Bordeaux, 2017. http://www.theses.fr/2017BORD0959.
Pełny tekst źródłaDue to an increasing and massive use, engineered nanoparticles are raising as potentialemerging contaminants in the environment, including aquatic ecosystems. While trophictransfer appears to constitute a major exposure route for organisms, scientific literature hasdifficulties to respond to the questions raised to explore the range of the interactions existingbetween nanoparticles and living organisms at different scales from the trophic interactionsto the cellular impacts. This problem is partly due to experimental difficulties inherent tothis exposure type. For this work performed in controlled laboratory conditions, sphericalgold nanoparticles (10 nm, coated with PEG-amines, positively charged) were chosen tostudy the trophic transfer and toxic effects on aquatic organisms. Trophic chains concernedseveral trophic levels (up to three) with a variety of species considered : the basis of thetrophic web with natural biofilms or microalgae, intermediate levels with grazing fish orsuspensivorous bivalves, and up to top food chain organisms, with the European eel, a carnivorousfish.With relatively low doses for exposures, this work tends to represent environmentalconditions. Integrative methodological approaches from subcellular to tissue levels(RT-qPCR, RNA-sequencing, histology) were performed in order to assess toxic impacts.The results indicate a high retention capacity of nanoparticles by natural biofilms. Followinga 21-day exposure, gold quantifications reveal a transfer from biofilms to grazing fish, witha gold distribution in all organs. Moreover, this transfer is associated with an inflammatoryresponse according to the histological lesions observed in the liver, spleen and muscle ofexposed fish. A longer food chain, with three trophic levels involving microalgae - bivalves- European eels, is set up to give a better representation of the complexity of trophic interactionsin the aquatic environment. It shows a significant transfer to the predatory fish.Transcriptomic analyses, using the RNA-sequencing approach, for the liver and the brain ofexposed eels by nanoparticles’ enriched food, highlight a joint response for these two organsin the biological processes associated with the immune system and its regulation, includingNOD-like receptors involved in inflammasome.All the experimental results suggest long-term harmful effects that nanoparticles would generatein aquatic ecosystems, emphasizing the ability of these contaminants to be transferredthroughout trophic chains
Purohit, Bhagyesh. "Precursors-guided synthesis of upconverting nanomaterials for near-infrared driven photocatalysis". Electronic Thesis or Diss., Lyon, 2021. https://n2t.net/ark:/47881/m6sn08q4.
Pełny tekst źródłaThe utilization of solar energy to solve environmental problems such as water detoxification, air purification and hydrogen production has attracted great interest from the scientific community over the last two decades. Solar photocatalysis is an interesting avenue to target all these environmental issues. Currently, technologies do not yet allow for the efficient use of a significant portion of the solar spectrum, namely the infrared, which corresponds to nearly ~48% of the total solar spectrum. This thesis aims at preparing nanocomposite materials that use these low energy solar photons by converting them into high energy UV and visible photons and then using them for classical photocatalysis. To achieve this, two major aspects of the preparation of this modified photocatalyst were emphasized. Firstly, the synthesis of materials that could efficiently convert currently unused photons and secondly, the preparation of their composite with TiO2, the most widely used photocatalyst.This doctoral thesis focuses on an approach based on "upconversion" in order to extend the range of use of the solar spectrum. To achieve this goal, two optimization strategies were addressed. The optimization of the quantum efficiency of upconversion nanoparticles (UCNPs) using new anhydrous precursors and, the preparation of UCNPs-TiO2 nanocatalyst using metallogels and/or core-shell structures. Finally, we test the objective of using low energy infrared solar photons by performing photocatalysis under IR irradiation only using the platform developed in this work
Buffet, Pierre-Emmanuel. "Évaluation du risque environnemental des nanoparticules métalliques : biodisponibilité et risque potentiel pour deux espèces clés des écosystèmes estuariens". Nantes, 2012. https://archive.bu.univ-nantes.fr/pollux/show/show?id=4222b036-2cc9-45e7-a146-038b3361bae3.
Pełny tekst źródłaThe advent of nanotechnologies is leading to the increase production of nanoparticles which could be released in the environment. Metal nanoparticles are used in a variety of commercial applications (bactericides, UV protection, medical imaging) and their toxicity is a source of concern. The aim of this work was to evaluate the fate of metal-bearing nanoparticles (Ag, Au, CuO, Cd, ZnO) in the marine environment and their effects on two marine endobenthic species : the bivalve Scrobicularia plana and the worm Hediste diversicolor by using a set of biomarkers at different levels of biological organization (behaviour, biochemical responses and genotoxicity). Effects were evaluated after exposure to different environmental sources (water, food, sediment independently or combined in mesocosms). In a number of cases, our work revealed a toxic effect of nanoparticles which is not due to the constituent metal but directly to the nanoproperties. Results show that biomarkers are promising tools to evaluate the ecotoxicity of nanoparticles and could be used to improve risk assessment
Barrick, Andrew. "Ecotoxicological study of the impact of nanomaterials on marine mussels through a high throughput screening approach". Thesis, Nantes, 2018. http://www.theses.fr/2018NANT4042/document.
Pełny tekst źródłaNanotechnology is an emerging field that is considered the industrial revolution of the 21st century. In this context, Manufactured nanomaterials (MNMs) will inevitably be released into the aquatic environment. In the objective of MNM regulation, the aim is to implement a read-across (grouping) approach based on high throughput screening (HTS) techniques as a way of quickly prescreening many MNMs in a cost-effective manner. Regulation is also focused on developing safe(r)-by-design (SbD) concept to integrate safety into the production of products. In this sense, for this work, an HTS platform on Mytilus edulis hemocytes has been developed using endpoints for cell viability as well as gene expression. Industrial case studies were investigated in in vitro testing following the HTS approach. In parallel an in vivo approach was assessed to determine if both testing strategies would come to the same conclusions on which product was SbD. In addition, a wide array of MNMs were also tested for effects on cell viability to establish a relevant database to investigate a grouping approach for MNM. This work demonstrated the relevance of using an HTS platform for M. edulis hemocytes to prescreen MNMs for environmental risk. Gene expression also provides a promising framework for investigating modes actions for MNM toxicity as well as the potential to develop adverse outcome pathways for SbD. This thesis established a preliminary database for ecotoxicology that could be implemented in a regulatory approach for NMs
Marchyk, Nataliya. "Molecularly imprinted polymers as synthetic receptors for glucuronates, and their use for biochemical sensing". Compiègne, 2012. http://www.theses.fr/2012COMP2053.
Pełny tekst źródłaMolecular recognition is a fundamental process in biological systems. The creation of synthetic receptors mimicking the biological processes is of high importance in practical application due to their higher stability to harsh environments, long on-shelf life and application flexibility comparing to natural counterparts. Molecularly imprinted polymers (MIP) readily meet these conditions. MIPs are tailor-made synthetic receptors that are able to specifically recognize a certain target molecule. Their synthesis is based on the presence of a molecular template that directs the self-assembly of functional monomers around. In an excess of cross-linking agent the monomers copolymerize, and subsequent removal of the template molecule generates three-dimensional binding sites in the material that are complementary to the template in size, shape and position of the functional groups. Due to complexity of composition and various influencing factors, the rational design should be employed in order to improve the performance of MIP systems. Core-shell nanoparticles provide a unique possibility to incorporate agents with optical or magnetic properties into the core, providing broader possibilities for MIPs application, such as in bioimaging and monitoring. The work of the thesis is focused on development of MIPs for the specific recognition of glucuronates in aqueous environment with outlook for applicability in biological systems. The rational design framework included molecular modelling, spectroscopic analysis and the design of experiments. Molecular modelling simulated intermolecular interactions and allowed to discover the most promising analyte-monomer combinations which could be verified in situ via spectroscopic (NMR) method. The design of experiments with multi-objective optimization allowed finding the composition of MIP with the best performance to glucuronate as well as to understand the effects of influencing factors, compounds concentrations in particular, onto the MIP performance. Förster resonance energy transfer (FRET) was applied in order to evaluate the recognition event of the target analyte in the MIP system. Bearing in mind the application in biological systems, a new approach for the synthesis of core-shell nanoparticles was proposed. The principle is based on one-pot synthesis by conventional emulsion polymerization of iniferter seeds which serve as cores for final particles. The up-converting particles (UCPs) possess unique optical properties to absorb the light at higher wavelength and emit it at lower wavelength. That makes them very promising in bioimaging, since the autofluorescence of biological samples can be decreased significantly. A novel strategy was proposed to synthesize composite core-shell nanoparticles where UCPs were employed as the second local light source to initiate the polymerization from the particles’ surface
Brackx, Gwennhaël. "Approche multidisciplinaire pour la détection de métaux lourds en environnements aquatiques". Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCC004/document.
Pełny tekst źródłaFreshwater management is a major problem all over the world. Anthropogenic activities related to industry, agriculture and human settlements are the main sources of water pollution. In order to makes policies for pollution prevention, rehabilitation of aquatic environments or waste water recycling, it is necessary to acquire massive data on water quality. Current contaminant monitoring methods have high costs and low frequency of measurement due to the incompatibility with field deployment. These two major brakes do not make it possible to monitor pollutant and especially heavy metal concentrations in aquatic environments at relevant spatial and temporal scales. Several international organizations, including the United Nations, have therefore recommended the development of new and better analytical methods.We propose here a technique for measuring heavy metal contaminants based on Surface Enhanced Raman Spectroscopy (SERS), which would allow a large scale deployment in the field.SERS has many advantages for environmental analysis including sensitivity, specificity, speed of measurement, adaptability to complex matrix and the moderate cost of portable instrument. We will therefore detail the construction of the SERS probe dedicated to the quantification of the target heavy metal ion Zn2+, which is a geochemical marker of anthropogenic contamination, as well as the data processing necessary for the establishment of quantification. Then, we will examine the robustness of the method of quantification with respect to the sources of variability that will inevitably be encountered in natural waters, when used directly in the field
Wang, Yuheng. "Etude cristallochimique de l'immobilisation de l'arsenic par les (hydr)oxydes de fer dans les environnements anoxiques". Paris 6, 2007. http://www.theses.fr/2007PA066384.
Pełny tekst źródłaDedeh, Amina. "Impact d'un sédiment dopé aux nanoparticules d'or ou de sulfure de cadmium sur un invertébré et un poisson d'eau douce". Thesis, Bordeaux, 2014. http://www.theses.fr/2014BORD0068/document.
Pełny tekst źródłaThe aim of this thesis was to determine the impact of two types of metal nanoparticles (cadmium sulphide - CdS - and gold - Au) on two aquatic models (tubifex worms and zebrafish Danio rerio). The approach has been to dope the Garonne sediment with the two types of nanoparticles and characterize the effect of this contamination on the two animals using multiple markers at different levels of biological organization (biochemical responses, neurotransmission activity, genotoxicity, gene expression and bioturbation activity). The effects were evaluated after exposure to contaminated sediment in experimental microcosms systems for twenty days. In a number of cases this work revealed an effect of the nanoparticles that was not due to metal but to the nanoparticulate properties. Indeed, in the case of CdS nanoparticles, we observed alterations in the genome as well as the modification of the bioturbation activity of worms tubifex in response to the contamination of nanoparticles but not to that of the ionic form. In this work we observed the release of gold nanoparticles from the sediment into the water column, and its potential bioavailability to fish. These nanoparticles were causing DNA damage in both organisms, modifying the expression of certain genes and increased acetylcholinesterase activity in zebrafish. Bioturbation results showed no effects of gold nanoparticles on the movement of worms
Mikosch, Cuka Andi. "Développement d'expérimentations mécanique in situ dans un microscope électronique à balayage et en transmission environnemental pour étudier à l'échelle nanométrique les propriétés et le comportement de nanoparticules sous contraintes mécanique et environnementale". Thesis, Antilles, 2019. http://www.theses.fr/2019ANTI0329/document.
Pełny tekst źródłaThe need to be able to visualize and manipulate nano-samples of mineral or biological materials, while conducting quantitative tensile, compression, bending and shearing experiments, led to the development of a nano-manipulation device that can evolve in an electron microscope. scanning in environmental transmission.Such a device will therefore make it possible to measure the various forces involved and to visualize the interface of interest during the various manipulations performed under controlled environmental conditions (gas partial pressure of 10-8 to 2500 Pa, liquid medium).For each of these experiments a precise and meticulous analysis of the images realized with the SEM allowed us to extract data making it possible to quantify the phenomena studied
Metjari, Anas. "Méthodologie de calibration DC/AC de sondes thermorésistives pour la microscopie thermique. Applications à la quantification des échanges pointe/environnements et à la mesure de résistances thermiques de contact". Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0291.
Pełny tekst źródłaThis PhD-thesis work focuses on the characterization of heat transport in nanomaterials by scanning thermal microscopy (SThM). This technique is used to measure the thermal properties of micro-objects at the scale of a few tens of nanometers. Achieving quantitative measurements at these scales remains a challenge due to the complexity of the heat exchanges at the interface between the probe and the sample. To address these issues, we have developed an experimental bench to control the environment and thus control the heat transfer modes. We have also set up a frequency approach (3ω) for the thermal study. The experimental signals obtained on this bench were compared and analyzed using detailed finite element modeling of the SThM tip. In this framework we have demonstrated the reliability of our bench to study materials with a thermal conductivity between 0.1 and 100 W/m.K
Shandilya, Neeraj. "Study of the (nano) particles emission during mechanical solicitation and environmental weathering of the products". Thesis, Compiègne, 2015. http://www.theses.fr/2015COMP2170/document.
Pełny tekst źródłaEngineering nanomaterials (ENM) like metal oxide nanoparticles, carbon nanotubes, nanofibers, etc. possess various innovative properties and their industrial use creates new opportunities. However, they also present new risks and uncertainties. There is an ever growing production and use of the products containing these ENM, like nanocomposites or nanocoatings, which result in an increasing number of workers and consumers exposed to ENM upon their emission (in the form of aerosols) from the products containing them. One of the most favored approaches, to minimize this emission, would be a preventive one which would focus on altering the product’s material properties during its design phase itself without compromising with any of its added benefits.This thesis advocates this approach. It attempts to understand the ENM emission phenomenon and its yielding mechanisms on the basis of combined experimental and theoretical approaches. The experimental set-up, developed during this thesis, is equipped with the necessary elements which can (i) seek to reproduce the real life activities on a laboratory scale (ii) identify the emission mechanism (iii) carry out both qualitative as well as quantitative*analysis of the emitted ENM simultaneously. Whilst the mean chosen for applying the mechanical solicitation or stress is an abrasion process, for the environmental weathering, it is an accelerated UV exposure process in the presence of humidity and heat. The results suggest that depending upon 18 material and process properties/parameters, the microscopic entities present on the surface of a product, called asperities, undergo mainly 4 types of removal mechanisms during abrasion. It is these mechanisms that decide the shape, size and the number of the aerosol particles emitted. Moreover, for the given test samples and experimental conditions studied during the thesis, application of the mechanical stresses alone was found to generate the emitted ENM aerosols in which ENM is always embedded inside the product matrix, thus, a representative product element. In such a case, the emitted aerosols comprise of both nanoparticles as well as microparticles. But if the mechanical stresses are coupled with the environmental weathering, then the eventual deterioration of the product, after a certain weathering duration, may lead to the emission of the free ENM aerosols too. All these experimental findings, pertaining to the effect of the mechanical stresses alone, have also been put into the perspective with classical material and mechanics state laws using a predictive analytical model. A close agreement** of the estimated results of this model with the experimentally measured ones has validated its functioning. This model was used to perform a sensitivity analysis on the aforementioned 18 parameters to rank the influence of a25% variation in each of their values on the particle emission for the given conditions.Thus, during the present thesis, both experimental and theoretical approaches have been developed to study the emission. Despite the fact that these approaches are perfectible, they can still be used during product design phase for the product to be “nanosafe by design”
Xiong, Tiantian. "Biodisponibilité des métaux et métalloïdes de particules micro- et nanométriques en relation avec leur phytotoxicité". Thesis, Toulouse, INPT, 2015. http://www.theses.fr/2015INPT0081/document.
Pełny tekst źródłaUltrafine particles including nanosized enriched with metal(loid)s (PM) are emitted into the atmosphere of industrial or urban areas, these PM can transfer into soil and water ecosystems and have consequences on plant quality and human health. In a global socio-scientific context that regulation on (eco)toxicity of chemicals and public space pressures are recently increased, studies of environmental and health impacts throughout the life cycle of PM are of crucial sanitary concern. The PhD aims first to study metal(loid)s present in the PM: their transfer kinetic and mechanism of phytoavailability, phytotoxicity, and human health risks-ingestion bioaccessibility. Then, through the case of vegetable gardens near an incinerator and a highway in China, a socio-scientific study was performed in order to give suggestions for sustainable environmental and health risk management for these sites. Vegetables can significantly accumulate metal(loid)s by foliar uptake when PM directly enter into leaves through stomata apertures. Ultrafine PbO and nano-CuO particles caused serious phytotoxicity (reduced biomass and gaseous exchange, and necrosis) after interaction with leaf surface. Phytotoxicity of metal(loid)s is not simply governed by their total concentration, but also depended on the potential bio-transformation. Electron paramagnetic resonance (EPR) analysis clearly evidenced copper speciation change in leaf tissues. Moreover, a significant influence of the nature of metal, plant species and the exposure pathways (foliar/root) on gastro-bioaccessibility of metal(loid)s had been demonstrated. For a social-scientific study near waste incinerator and roadside, we found that atmosphere PM fallouts can induce significant metal foliar uptake in addition to soil-plant transfer. The relatively high human bioaccessibility of metal (60-79%) was measured, suggesting a potential health risk in the case of regular consumption of polluted vegetables. Vegetable gardens present a low (waste incinerator) or moderate (highway) health risk with respect to human consumption quantity of the investigated vegetables, but exposure to different organic pollutants in addition to metals is often possible. Our studies highlight the importance of taking atmosphere and soil quality into account for estimating the quality of consumed plants grown in anthropic areas (farms and kitchen gardens), and for sustainable management of urban agricultures
Perrier, Fanny. "Nanocontamination d'organismes aquatiques par des particules inorganiques : transfert trophique et impacts toxiques". Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0959/document.
Pełny tekst źródłaDue to an increasing and massive use, engineered nanoparticles are raising as potentialemerging contaminants in the environment, including aquatic ecosystems. While trophictransfer appears to constitute a major exposure route for organisms, scientific literature hasdifficulties to respond to the questions raised to explore the range of the interactions existingbetween nanoparticles and living organisms at different scales from the trophic interactionsto the cellular impacts. This problem is partly due to experimental difficulties inherent tothis exposure type. For this work performed in controlled laboratory conditions, sphericalgold nanoparticles (10 nm, coated with PEG-amines, positively charged) were chosen tostudy the trophic transfer and toxic effects on aquatic organisms. Trophic chains concernedseveral trophic levels (up to three) with a variety of species considered : the basis of thetrophic web with natural biofilms or microalgae, intermediate levels with grazing fish orsuspensivorous bivalves, and up to top food chain organisms, with the European eel, a carnivorousfish.With relatively low doses for exposures, this work tends to represent environmentalconditions. Integrative methodological approaches from subcellular to tissue levels(RT-qPCR, RNA-sequencing, histology) were performed in order to assess toxic impacts.The results indicate a high retention capacity of nanoparticles by natural biofilms. Followinga 21-day exposure, gold quantifications reveal a transfer from biofilms to grazing fish, witha gold distribution in all organs. Moreover, this transfer is associated with an inflammatoryresponse according to the histological lesions observed in the liver, spleen and muscle ofexposed fish. A longer food chain, with three trophic levels involving microalgae - bivalves- European eels, is set up to give a better representation of the complexity of trophic interactionsin the aquatic environment. It shows a significant transfer to the predatory fish.Transcriptomic analyses, using the RNA-sequencing approach, for the liver and the brain ofexposed eels by nanoparticles’ enriched food, highlight a joint response for these two organsin the biological processes associated with the immune system and its regulation, includingNOD-like receptors involved in inflammasome.All the experimental results suggest long-term harmful effects that nanoparticles would generatein aquatic ecosystems, emphasizing the ability of these contaminants to be transferredthroughout trophic chains
Théoret, Trevor. "Détermination du destin des nanoparticules d'argent dans les eaux usées et dans les biosolides en utilisant la microscopie en champ sombre et analyse hyperspectrale". Thèse, 2016. http://hdl.handle.net/1866/19073.
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