Rozprawy doktorskie na temat „Sulfure de cadmium – Environnement”
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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
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". 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
BOUCHENAKI, CHOUKRI. "Preparation, caracterisation et proprietes photothermiques bistables de couches minces de sulfure de cadmium". Université Louis Pasteur (Strasbourg) (1971-2008), 1991. http://www.theses.fr/1991STR13105.
Pełny tekst źródłaCHERKAOUI, EDDEQAQI NOUR-EDDINE. "Etude de la bistabilite absorptive dans le sulfure de cadmium : dynamique de commutation". Université Louis Pasteur (Strasbourg) (1971-2008), 1990. http://www.theses.fr/1990STR13037.
Pełny tekst źródłaOberlé, Jean. "Non-linearites optiques du sulfure de cadmium a la temperature ambiante : caracterisation et applications". Université Louis Pasteur (Strasbourg) (1971-2008), 1992. http://www.theses.fr/1992STR13026.
Pełny tekst źródłaFrégnaux, Mathieu. "Élaboration et caractérisation de nanocristaux de sulfure de cadmium - dépôt en couches minces nanostructurées". Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0284/document.
Pełny tekst źródłaTwo chemical methods are developed to synthesize cadmium sulfide (CdS) nanocrystals (NC) in bottom-up approach: (i) single-source precursor methodology and (ii) microwave synthetic route. These two growth techniques are complementary in the size range obtained and allow production of small NC (2.8 nm - 5.2 nm) in only (i) 120 min and (ii) some minutes. A joint technique characterization protocol is developed to study the synthesized NC. Mass spectrometry (MS) coupled to soft ionization sources allows to control the purity and stability of the precursors and to estimate the NC size and size distribution. These estimations are confirmed by transmission electron microscopy (TEM). Comparison between SM and TEM results suggests that NC have (i) spherical and (ii) prolate shapes. X-ray diffraction reveals nanoparticle crystalline structure in (i) wurtzite and (ii) zinc blende symmetries. Room temperature optical spectrometry (absorption and photoluminescence - PL) evidences quantum confinement effects by the shift of the excitonic response as a function of the NC size, in the blue-UV spectral range. These results are consistent with the well-known empirical energy-size correspondence. For optoelectronic application purpose, thin film deposition of polymer (PMMA) containing CdS NC is initiated by spin coating. The previous characterization protocol, extended to techniques dedicated to thin film studies, shows that NC maintain their integrity and PL properties after inclusion in PMMA layer
Ortega, Borges Raúl. "Etude du depot de couches minces semiconductrices de sulfure de cadmium par voie chimique en solution". Paris 6, 1994. http://www.theses.fr/1994PA066749.
Pełny tekst źródłaEbothe, Jean. "Etude des proprietes photoelectrochimiques des couches minces polycristallines de sulfure de cadmium deposees par pulverisation reactive". Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13012.
Pełny tekst źródłaRIBLET, PHILIPPE. "Etude comparee des nonlinearites optiques de nanocristaux et de monocristaux de sulfure et seleniure de cadmium". Université Louis Pasteur (Strasbourg) (1971-2008), 1995. http://www.theses.fr/1995STR13102.
Pełny tekst źródłaEbothe, Jean. "Etude des propriétés photoélectrochimiques des couches minces polycristallines de sulfure de cadmium déposées par pulvérisation réactive". Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37604791d.
Pełny tekst źródłaSENE, CHEIKH. "Proprietes electrochimiques et photovoltaiques du poly(methyl-3 thiophene) electrolytique sur films polycristallins de sulfure de cadmium". Université Louis Pasteur (Strasbourg) (1971-2008), 1992. http://www.theses.fr/1992STR13155.
Pełny tekst źródłaLAMI, JEAN-FREDERIC. "Proprietes optiques non-lineaires induites par absorption a deux photons. Un semi-conducteur type : le sulfure de cadmium". Université Louis Pasteur (Strasbourg) (1971-2008), 1997. http://www.theses.fr/1997STR13040.
Pełny tekst źródłaDjazouli, Nasr-Eddine. "Biolixiviation du sulfure de cadmium en présence de thiobacillus ferrooxiadans : optimisation des paramètres opératoires et réalisation d'un procédé en cuve agitée". Châtenay-Malabry, Ecole centrale de Paris, 1994. http://www.theses.fr/1994ECAP0393.
Pełny tekst źródłaAntoine, Claire. "Composés d'insertion inorganiques en films de Langmuir-Blodgett". Paris 11, 1989. http://www.theses.fr/1989PA112328.
Pełny tekst źródłaBaliardini, Cecilia. "Genetic analysis of cadmium tolerance in Arabidopsis halleri: contribution of CAX1". Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/218852.
Pełny tekst źródłaDoctorat en Sciences
info:eu-repo/semantics/nonPublished
Chottier, Claire. "Composés Organiques Volatils du Silicium et sulfure d'hydrogène - Analyse - Traitement - Impact sur la valorisation des biogaz". Phd thesis, INSA de Lyon, 2011. http://tel.archives-ouvertes.fr/tel-00715818.
Pełny tekst źródłaKa, Oumar. "Composes 2-6 serigraphies : preparation et caracterisation de cds et cdte". Paris 6, 1988. http://www.theses.fr/1988PA066319.
Pełny tekst źródłaAfifi, Hussein. "Couches évaporées de CdS et CdTe : étude des propriétés et application à la réalisation de photopiles solaires". Paris 7, 1988. http://www.theses.fr/1988PA077173.
Pełny tekst źródłaRaulin-Woznica, Katarzyna. "Étude du dopage par des ions actifs et des nanoparticules semi-conductrices de matériaux sol-gel pour l'optique : interaction dopant-matrice et croissance localisée de nanoparticules par irradiation laser". Thesis, Lille 1, 2008. http://www.theses.fr/2008LIL10100/document.
Pełny tekst źródłaThis work concerns the elaboration by sol-gel process and the characterization of porous SiO2 xerogels doped with active ions and/or with semiconducting nanoparticles of CdS. The aim of the study was to contribute to the comprehension of the doping effects on structural and optical properties of the final material. We showed by Raman spectroscopy and nitrogen absorption-desorption that the insertion of active ions, such as Cd2+, Pb2+ or Eu3+, changes the kinetics and the mechanisms of the gelation and densification of the network of SiO2. The choices of the pH and of the concentration of the doping ion have distinct effects on the kinetics. This study was completed by emission spectroscopy using Eu3+ ion as luminescent probe to describe the environment of this ion in the porous matrix. The SiO2 xerogels were post-doped with CdS nanoparticles. The post-doping technique consists in the diffusion of an aqueous solution containing cadmium and sulphur precursors in the porous matrix. The nanoparticles crystallize in situ by heat treatment. The nanoparticle size and their emission properties were determined by UVvisible absorption as well as emission and excitation spectroscopies. The results showed the influence on optical properties of trap levels introduced by the surface defects of nanoparticles and an enhancement of the Eu3+ emission in SiO2 xerogel co-doped with CdS :Eu3+. A second method for the formation of CdS nanoparticles was used. CdS microstructures were created locally by pulsed laser irradiation of sol-gel matrices containing the CdS precursors
Bui, Hong Son. "Etude de l'influence physicochimique des environnements gazeux sur le comportement tribomécanique du bi-sulfure de molybdène MoS2". Poitiers, 2012. http://www.theses.fr/2012POIT2331.
Pełny tekst źródłaThe aim of this study is to characterize experimentally and theoretically the evolution of the friction coefficient of molybdenum disulfide MoS2 in various gases such as in the high vacuum at 10-5 Pa and in the various components gases of the ambient air. We present and discuss the experimental results of the contact XC48/ MoS2/XC48. Our tribological tests are performed on a pin on disk tribometer which located in an ultra high vacuum chamber and which is equipped with one system of gas introduction valves. To clarify the effect of each gas, tribological tests were carried out in the high vacuum (10-5 Pa), in the helium and in the argon at 105 Pa as inert gases, in the nitrogen and in the carbon dioxide at 105 Pa as the less reactive gases, in the oxygen at 105 Pa as the strong reactive gas, in the water vapour with a permanent dipole and in the air ambient with or without the presence of moisture. The tribological nature of molybdenum disulfide MoS2 obtained in high vacuum will be discussed. The influence of gases on the tribological behaviour of molybdenum disulfide will be also discussed and interpreted according to the dipolar character of these gases. A simple calculation of interaction forces MoS2-gas in terms of Van der Waals forces will be presented. Moreover, the influence of Van der Waals forces according to the nature of the gas around the tribocontact on the elastic tensor or on the stress of cleavage of the anisotropic lamellar layers of MoS2 will be discussed too
Juodkazis, Saulius. "Propriétés structurales et optiques des couches minces guidantes dopées par des nanocristaux de CdS". Lyon 1, 1997. http://www.theses.fr/1997LYO10272.
Pełny tekst źródłaOthmani, Abdelhak. "Nanocristaux de CdS confinés dans un xérogel de silice : élaboration et caractérisation : propriétés optiques non-linéaires". Lyon 1, 1994. http://www.theses.fr/1994LYO10146.
Pełny tekst źródłaMoussavou, Moudouma Chris Fabien. "Etude des mécanismes d’accumulation du cadmium chez Arabidopsis thaliana (écotype Wassilewskija) et chez un mélèze hybride (Larix x eurolepis) par des approches moléculaire et développementale". Limoges, 2010. https://aurore.unilim.fr/theses/nxfile/default/f5bd5ea2-630d-4f8b-9f9e-8f604b8f77c7/blobholder:0/2010LIMO4011.pdf.
Pełny tekst źródłaThe presence of trace metal elements in the environment led plants to develop diverse defense mechanisms. However, no exhaustive study (molecular, biochemical and developmental) had been led to date in Arabidopsis thaliana in response to cadmium (Cd) stress. Our work thus consisted in the study of defense mechanisms in response to Cd in the ecotype Wassilewskija (Ws) of Arabidopsis thaliana using molecular and biochemical approaches and the study of phonotype. A “stress-induced morphogenic response” (SMIR) is observed in the roots of 14 day-old plants since 50 μM Cd. This SMIR is characterized by the shortening of the main root and multiple initiations of secondary roots. At the same time, the activity of the enzymes involved in the synthesis of phytochelatins (PC) (glutamylcystein synthetase, glutathione synthetase and phytochelatin synthase) is stimulated in the whole plant, PC and Cd however being more accumulated in roots than in shoots. At the transcriptional level, only PC synthase is spatially regulated in the presence of 100 μM Cd with an up-regulation of the genes PCS1 and PCS2 in the shoots and the roots respectively. The transcriptomic study on the whole genome of A. Thaliana showed an up-regulation the of genes coding particularly potential Cd transporters in roots and shoots, what is in agreement with the presence of the metal in various organs of the plant. Finally, we showed that the ecotype Ws is a better Cd tolerant than ecotypes Columbia and Landsberg erecta. Our work also focused on the response to Cd of young hybrid larch plants (Larix x eurolepis) obtained by somatic embryogenesis. A part from a shortening of the main root, the development of the larch is not altered with 1. 5 mM Cd. Although the PC synthesis pathway is also stimulated in response to Cd, another way of metal chelation, probably at the cell wall level, seems to be involved in tolerance mechanisms of the larch
Oger-Duroy, Cécile. "Etude des bactéries résistantes au cadmium portant le gène cadA dans un environnement naturel contaminé par les métaux lourds : l'estuaire de la Seine". Rouen, 2003. http://www.theses.fr/2003ROUES019.
Pełny tekst źródłaIn the Seine estuary cadmium-resistant bacterial communities was studied with different approaches of classical microbiology and molecular ecology. Molecular quantification of the cadA gene level in the total extracted DNA from environmental samples (water and sediments) in the microbial community, enabled us to study modifications in the genetic background of these communities. Those modifications could be related to the selection pressure by cadmium occurring on bacterial communities in contaminated sites such as the Northern intertidal mudflats. Moreover, high level of cadA gene in the water column of the mouth could be relied to the hydrodynamic of the environment during the maximum turbidity zone formation in low riverflow periods. This study focalized on the Staphylococcus population harboring cadA gene. The conservation of cadA gene sequences in the bacteria of this genus could be related to the dissemination of this gene with plasmids or insertion sequences IS257 intermediates
Le, 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
Sigot, Léa. "Epuration fine des biogaz en vue d'une valorisation énergétique en pile à combustible de type SOFC : Adsorption de l'octaméthylcyclotétrasiloxane et du sulfure d'hydrogène". Thesis, Lyon, INSA, 2014. http://www.theses.fr/2014ISAL0098/document.
Pełny tekst źródłaBiogas energy use is hampered by the presence of trace compounds. Three contaminant families are particularly detrimental for external reforming catalysts and solid oxide fuel cell (SOFC) anodes: sulfur-containing compounds, volatile organic silicon compounds (VOSiC) and chlorinated compounds. Therefore, a thorough biogas treatment is necessary for such an application. This experimental work deals with the development of a polishing treatment for the adsorption of these contaminants. Adsorbents were selected for their efficiency to remove hydrogen sulfide (H2S – sulfur-containing compound), octamethylcyclotetrasiloxane (D4 – VOSiC) and cis-1,2-dichloroéthene (C2H2Cl2 – chlorinated compound), molecules representative of the three harmful families. The studied zeolite showed the best efficiency for H2S removal whereas silica gel performed best for D4 adsorption. A parametric study highlighted the influence of adsorbent bed height, contaminant concentration, gas flow rate, the presence of contaminants in mixture and humidity on purification performance. Adsorption tests with a raw landfill biogas showed that it is possible to guarantee an H2S concentration below the 1 ppmvH2S tolerance limit of the reformer. Using adsorbent physicochemical characterizations, hypothesis about retention mechanisms were proposed for the couples zeolite + H2S and silica gel + D4. H2S is adsorbed and then oxidized into elemental sulfur at the surface of the zeolite. During the adsorption on silica gel, D4 seems to polymerize on the surface. These two phenomena prevent the regeneration of the adsorbents. A first modeling approach of the adsorption phenomena involved for the couple silica gel + D4 allowed the determination of the global mass transfer coefficient. Experimental breakthrough curves obtained for different masses of adsorbent were successfully simulated. Some “dimensioning rules” were proposed for the industrial design of a polishing treatment able to produce a biogas with the quality required to feed an SOFC. The techno-economic analysis showed that the SOFC solution is technically feasible but not economically viable because SOFC technology is still too costly compared to conventional conversion devices. However, the solution seems promising from an environmental point of view
Nguyen, Van Trang. "Sorption et désorption du cadmium dans deux sols agricoles amendés de composts et de coquilles d'oeufs de poules". Thesis, Université Laval, 2010. http://www.theses.ulaval.ca/2010/26631/26631.pdf.
Pełny tekst źródłaDelhaye, Hélène. "Développement d'un bioessai de toxicité chronique en microcosme aquatique de laboratoire et évaluation de l'outil au travers de l'étude des effets du cadmium". Phd thesis, INSA de Lyon, 2012. http://tel.archives-ouvertes.fr/tel-00814732.
Pełny tekst źródłaPaille, Françoise. "Xérogels de silice dopés par des nanocristaux de CdS : élaboration, caractérisation structurale et propriétés optiques". Lyon 1, 1997. http://www.theses.fr/1997LYO10140.
Pełny tekst źródłaSouchon, Vincent. "Ingénierie moléculaire et fluorescence pour la reconnaissance de cations toxiques". Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2007. http://tel.archives-ouvertes.fr/tel-00255005.
Pełny tekst źródłaFaye, Djibril. "Détection fluorimétrique en circuit microfluidique des ions Pb2+, Hg2+ et Cd2+ en milieu aqueux". Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2011. http://tel.archives-ouvertes.fr/tel-00722906.
Pełny tekst źródłaGeszke-Moritz, Malgorzata. "Synthesis of stable and non-cadmium containing quantum dots conjugated with folic acid for imaging of cancer cells". Thesis, Vandoeuvre-les-Nancy, INPL, 2011. http://www.theses.fr/2011INPL066N/document.
Pełny tekst źródłaSemiconductor QDs are tiny light-emitting crystals, and are emerging as a new class of fluorescent labels for medicine and biology. The aim of this work was to develop a new class of non-toxic QDs probes with essential attributes such as water dispersibility, photostability, biocompatibility, high luminescence and possible excitation with low-energy visible light, using simple processing method. Such nanoprobes could be used for bio-imaging of cancer cells. In the performed studies, I focused on ZnS and ZnSe QDs as they are cadmium-free and might be excited biphotonically.The synthesis protocols of ZnS and ZnSe QDs doped with two ions such as Mn or Cu and stabilized by 3-mercaptopropionic acid or 1-thioglycerol were established, followed by NCs characterization (diameter, surface charge, photophysical properties, …) using analytical techniques such as spectrophotometry UV-vis, fluorimetry, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), dynamic light scattering (DLS), infra-red analysis (FT-IR), thin layer chromatography (TLC) and electron paramagnetic resonance (EPR). The cytotoxicity of synthesized bare and conjugated NPs was evaluated on cancer cell lines using MTT, XTT and ferrous oxidation-xylenol orange assay.Finally, chosen well fluorescent and weakly toxic types of as-prepared and characterized QDs were used for bio-imaging of cancer cells. In these experiments, FA-functionalized NCs were excited biphotonically. The performed experiments showed the potential of QDs as cancer cells fluorescent markers and that they accumulate around the cell nuclei
Ha-Thi, Minh-Huong. "Nouvelles architectures supramoléculaires à base de ligands phosphorés fluorescents : synthèse, études photophysiques et applications". Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2007. http://tel.archives-ouvertes.fr/tel-00254039.
Pełny tekst źródłaPapazia, Mariam Eugénie. "Comportement de molécules biocides thiocyanées dans l'environnement : étude de leur dégradation : décomposition du sulfure de diméthyle, modèle de molécule soufrée, légère, malodorante : interactions de surface DMS-TiO2". Université Joseph Fourier (Grenoble), 1995. http://www.theses.fr/1995GRE10172.
Pełny tekst źródłaGERARD, BRUNO. "Luminescence retardee stimulee electriquement dans les sulfures de zinc et de cadmium actives au cuivre, a l'or ou a l'argent et coactives a l'aluminium : application a un imageur mammographique numerique a memoire". Paris 6, 1988. http://www.theses.fr/1988PA066252.
Pełny tekst źródłaArgane, Rabei. "Valorisation des rejets miniers à faible teneur en sulfures comme granulats pour mortiers". Thesis, Lyon, INSA, 2015. http://www.theses.fr/2015ISAL0039.
Pełny tekst źródłaMine tailings represent the finely ground industrial by products generated throw beneficiation of ore minerals. During mine exploitation, these tailings are generally transported in slurry form to large storage facilities, called tailings ponds or impoundments. These facilities are, in most cases, difficult to manage and expensive to rehabilitate. They are responsible for the generation of important environmental impacts and significant ecological disruptions, depending on their pollution potential, management technique, physical stability and the climate conditions. In this context, numerous studies have been conducted to develop new techniques for a sustainable management of mine tailings. The feasibility of reusing some tailings in the construction sector as cementing materials and additives for mortars or concretes were successfully achieved. However, the majority of the conducted studies are still at laboratory stages. Moreover the reuse of tailings as construction material is yet subject of numerous difficulties in term of social acceptance. Various parameters are also of concern, especially the physical and chemical stability of tailings as well as their eco-compatibility. In parallel, the uncontrolled reuse of low sulfide tailings as construction material is increasing in some developing countries (e.g. Morocco). In fact, nearby some abandoned mine sites, these tailings are considered as natural sands and are used for the manufacture of surface finishing mortars. This traditional recycling may constitute mechanical and environmental risks, principally related to tailings mechanical unconformity and to their non-negligible residual metal concentrations. Therefore, the aim of the current research is to evaluate the actual impact of two Moroccan mine tailings (named Zeida and Mibladen), commonly used as aggregates in the Upper-Moulouya region, on the mechanical properties of mortars and on their long term environmental behavior. This work has also as specific aim, to study the technical feasibility of using low sulfide tailings as sand substitute for the manufacture of rendering and masonry mortars. To attain this aim, a thorough characterization of the physical, chemical and mineralogical properties as well as the geochemical behavior of mine tailings was carried out. Mechanical properties of tailings-based mortars were then measured and compared to reference samples (sand-based mortars) using different tests such as setting time, entrained air volume and compressive strength. In parallel, mortars durability and hydration products were evaluated by mean of durability tests (wetting drying cycles, sulfate attack and acid rain simulation) and analytical methods (scanning electron microscopy, X-ray diffraction and thermo-gravimetric analysis). Finally, mortar samples were submitted to various leaching tests to evaluate the pollution potential of these matrices
Pouget, Stéphanie. "Contribution à l'étude de l'influence de la dilution sur les propriétés magnétiques de composés isolants frustrés". Toulouse, INSA, 1993. http://www.theses.fr/1993ISAT0039.
Pełny tekst źródłaBen, Ahmed Nada. "Conception de bio-indicateurs de polluant organique et de métaux lourds par encapsulation de micro-algues dans une matrice de silice synthétisée par le procédé sol-gel". Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCC247.
Pełny tekst źródłaThe work is an interdisciplinary framework, at the interface of the sol-gel chemistry, biology and physics of materials. First, we are interested to the study of a silica matrix obtained by sol-gel process from a mixture of colloidal silica and sodium silicate. The goal was to understand the interactions between the precursors and to study the effect of different synthesis parameters on the structure of the matrix in order to find the best optical and mechanical properties. These matrices have been extensively characterized using various techniques (UV-Visible absorption, IR, TGA, BET, NMR, TEM and SEM). This study allows us for the first time to choose final properties and to specify the initial combination to get them in terms of concentrations of precursors and pH. Next, we studied the effect of the matrix properties on the survival of photosynthetic encapsulated cells and we got phyco-compatible materials with a wide range of optical and mechanical properties. After precising the best synthesis conditions for the survival of microorganisms, one could proceed to study the functionality in the presence of toxic contaminants (heavy metals Cd (II) and Pb (II) and a polycyclic aromatic hydrocarbon: anthracene) and we managed to get a functional biosensor. Interestingly, some specificity of detection could be obtained according to the combination of microalga / selected matrix
Mambingo, Doumbe Samuel. "Simulation de la phase gazeuse des réactions tribochimiques des additifs phosphorés et soufrés". Thesis, Ecully, Ecole centrale de Lyon, 2012. http://www.theses.fr/2012ECDL0063.
Pełny tekst źródłaMastering the addivation is one of the biggest issues for the lubricants formulation, especially in the automobile industry. However automotive lubricants are very complex systems due to the numerous additives mixed with base oils. Many interactions can occur between additives, especially between surface additives. Organic phosphites and organic polysulphides have already demonstrated their effectiveness as surface additives. However, despite their widespread use in the formulations of automotive lubricants, few studies deal with the interactions taking place between these two types of compounds. The aim of this study is to understand the interactions, antagonistic or synergetic effect between these kinds of additives using Gas Phase Lubrication (GPL) approach. A Environmental Controlled Tribometer (TEC) was used as a tool to simulate the interaction between organophosphate additives and polysulfurous additives. In situ surface analysis was performed in the tribofilm formed during friction using of X-ray Photoelectron Spectroscopy (XPS) and Auger Electron Spectroscopy(AES) in order to avoid any oxidation or air contamination. The molecules selected for the study can be same as the additive like the TPS molecules which are widely used as lubricant additives. Howeverto simulate the phosphite chemical function of phosphite additives, we need to select smaller molecule having the same chemical function. These molecules are dimethyl phosphite (DMPi), trimethylphosphate (TMPi) for simulating the phosphite chemical function and organic polysulphides (TPS44and TPS32). The study of the tribochemical reactions of organic phopshites allowed to clearly characterise the ambivalence of DMPi, which can react like a phosphite and induce iron phosphide formation or react like a phosphate. Ab initio numerical simulation on TMPi dissociative adsorption was carried out to identify the reactions pathways leading to iron phosphide formation. The tribochemical reaction of TPS44 on metallic iron surface leads to the formation of iron disulphidebased tribofilm. The binary vapours mixtures studied by GPL allowed to clearly identify the importance of the vapour concentration ratio between phosphite and polysulphide. Liquid phase experiments were also carried out to confirm the trend observed in GPL approach
Ben, slimen Fedia. "Caractérisation des verres luminescents préparés par la méthode sol-gel". Thesis, Angers, 2016. http://www.theses.fr/2016ANGE0019/document.
Pełny tekst źródłaGlasses doped with rare earth ions and/or semiconductor nanoparticles continues to be the subject of several studies due to their effectiveness in optoelectronic fields. Indeed, these materials are among the potential candidates for photonic applications such as optical fiber amplifiers, light converters, sensors and 3D waveguides. As part of this thesis, silica-based glasses (SiO2) doped with europium ions (Eu3+) were prepared by the sol-gel process. In order to better disperse the rare earth ions and improve their emission, the glasses were codoped with phosphorus and/or aluminum. Semiconductor nanoparticles (CdS) were also introduced into the glass in order to increase the absorbance of the excitation light and to obtain a more intense emission of Eu3+ ions. The prepared glasses were analyzed by photoluminescence and by the technique of Fluorescence line narrowing (FLN). These experimental measurements were followed by theoretical simulations using the molecular dynamics method (DM) to study the effect of phosphorus and/or aluminum on the local environment of the europium ions and their dispersion in the vitreous matrix. The presence of two types of europium ion sites in the glass silicophosphates has been demonstrated and confirmed by two techniques (FLN and DM). The effect of CdS nanoparticles on the emission of Eu3+ ions in a glass silicophosphate was also studied and it was shown that the emission of Eu3+ ions is considerably dependent on theconcentration of CdS nanoparticles and annealing temperature
Saifi, Ali. "Contribution à l'étude des propriétés magnétiques des systèmes spinelles isolants CdCr2xIn2-2xS4 et ZnCr2xGa2-2xO4 : phases type verre de spin". Paris 6, 1986. http://www.theses.fr/1986PA066519.
Pełny tekst źródłaGasquet, Valentine. "Epuration d’H2S du biogaz à partir de résidus de traitement thermique bruts et formulés : Comparaison des performances et compréhension des mécanismes d’adsorption". Electronic Thesis or Diss., Lyon, 2020. http://www.theses.fr/2020LYSEI106.
Pełny tekst źródłaBiogas is a renewable, local, non-intermittent energy which can be used in different ways. Before its valorization, it is necessary to clean this gas, notably to remove hydrogen sulfide (H2S). This component can be removed by adsorption on noble materials such as activated carbon (AC). In order to reduce the waste disposal and participate to circular economy while reducing the cleaning costs, the use of thermal treatment residues (TTR), close to traditional adsorbents, receives more and more attention to remove H2S from biogas. First, an analytical method was developed in order to quantify the amount of sulfur present in different materials with TGA-DSC under air and nitrogen atmosphere. The amount of organic matter in the material and its porosity affect elemental sulfur oxidation when experiments were carried out with air and also its vaporization. Organic matter vulcanization was also observed, leading to the formation of longer and more complex carbon chains. During this thesis, three types of TTR were used for the removal of H2S from a landfill biogas: biomass ash (BA), biochar (BCH) and incinerated sewage sludge (ISS). It was found that two of them are not sufficiently efficient as themselves for H2S removal. Final adsorption capacities of BCH and ISS were quite low and these materials never adsorbed the total amount of H2S entering in the reactor. On the contrary, BA was a good adsorbent with a final adsorption capacity of 175 mgH2S/gDM. The materials characterization let us understand the adsorption mechanisms leading to H2S removal. For all the materials, at the beginning of the experiment, the conditions are favorable to H2S chimisorption into elemental sulfur. However, while BA and ISS have a buffering capacity leading to the basicity of the solid, BCH begin acid. Then, non-selective physisorption takes place with this TRR. ISS adsorption was limited by its too low porosity and BCH by the absence of catalyst minerals and its too low density. Comparison of removal performances of TTR also highlights the influence of humidity on adsorption efficiency for ISS as well as the effect of gas flow on experimental adsorption test. With the adsorption efficiency comparison between the different TTR, it seems interesting to associate materials with different characteristics in order to try to obtain more efficient adsorbents and consequently find a valorization way for all the TTR. Adsorption experiments with a synthetic biogas were first performed in order to assess the potential of various formulations. A strong synergy was observed with the formulation with ISS and 10-30 % of AC. The encouraging results obtained with the synthetic biogas were confirmed with an experiment using a landfill biogas and a larger reactor. ISS itself was indeed a bad adsorbent but the addition of AC provides enough porosity to efficiently adsorb H2S
Benjelloun, Nadia. "Caracterisation des niveaux profonds dans le materiau photorefractif bi : :(12) geo::(20) par analyse de transitoires de courant photo-induit". Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13183.
Pełny tekst źródłaChebbo, Ghassan. "Solides des rejets pluviaux urbains : caractérisation et traitabilité". Phd thesis, Ecole Nationale des Ponts et Chaussées, 1992. http://pastel.archives-ouvertes.fr/pastel-00569043.
Pełny tekst źródłaBrillant, Ève. "Effets de l'intoxication au chlorure de cadmium chez la truite mouchetée, Salvelinus fontinalis, Mitchill". Thèse, 1993. http://constellation.uqac.ca/1320/1/1485704.pdf.
Pełny tekst źródłaBonet, Amandine. "Effets du cadmium sur l'expression d'enzymes de biotransformation au cours de la différenciation entérocytaire". Mémoire, 2011. http://www.archipel.uqam.ca/4873/1/M12444.pdf.
Pełny tekst źródłaPerceval, Olivier. "Évaluation de la métallothionéine comme biomarqueur d'effets toxiques chez le bivalve d'eau douce Pyganodon grandis dans un environnement aquatique contaminé par les métaux traces". Thèse, 2004. http://hdl.handle.net/1866/17039.
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