Academic literature on the topic 'Composé polaire'
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Journal articles on the topic "Composé polaire"
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Hamelin, Louis-Edmond. "Le Nord et l’hiver dans l’hémisphère boréal." Cahiers de géographie du Québec 44, no. 121 (April 12, 2005): 5–25. http://dx.doi.org/10.7202/022879ar.
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1. La notion de nordicité exploite les dimensions lexicales des racines nord et nordique, c'est-à-dire qu'elle reflète la diversité tant naturelle que culturelle des hautes latitudes de l'hémisphère boréal. Des dictionnaires français et anglais font de nordicité et nordicity des canadianismes. 2. La question de la localisation du Nord a fait naître un indice intégré (1963) composé de dix facteurs et conduisant à l'identification de « valeurs polaires » ou vapos. L'isoligne de 200 vapos suggère la limite sud du Nord. Selon le même indice, la nordicité géographique moyenne du Canada apparaît plus élevée que celle du Norden et même celle de la Russie. Trois zones longitudinales circumterrestres sont identifiées : le Moyen Nord, le Grand Nord et l'Extrême Nord. 3. Durant l'hiver, la froidure occupant des espaces de la zone tempérée fait naître une nordicité saisonnière. Même le Sud des États-Unis n'est pas exempt de manifestations hivernales. Cette hivernité, à l'échelle de mois ou de jours, est à la fois un cosmétique et un vécu atténués d'une nordicité polaire maîtresse. Cet article propose une définition socioclimatique de l'hiver qui considère le tout du Nord et de l'hiver.
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Le Curieux, F., F. Erb, and D. Marzin. "Identification de composés génotoxiques dans les eaux de boisson." Revue des sciences de l'eau 11 (April 12, 2005): 103–18. http://dx.doi.org/10.7202/705333ar.
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Depuis la mise en évidence de trihalométhanes dans les eaux potables en 1974, de multiples travaux ont démontré la présence de nombreux composés génotoxiques dans l'eau de boisson. L'eau potable obtenue à partir d'eau de surface subit un traitement incluant généralement une étape de chloration. Il est aujourd'hui largement admis que l'activité génotoxique des eaux de boisson provient principalement de la chloration des substances humiques, composés organiques naturels contenus dans l'eau brute et issus de la dégradation des déchets animaux et végétaux. Les très faibles concentrations en composés génotoxiques dans les eaux potables nécessitent la concentration des échantillons, procédé qui risque toutefois de modifier la génotoxicité. Plusieurs tests mettant en oeuvre des cellules procaryotes ou eucaryotes, des plantes ou des mammifères, ont permis de mettre en évidence les effets génotoxiques dans des eaux potables chlorées. L'identification des composés génotoxiques est réalisée au moyen des données de la spectrométrie de masse et de la spectroscopie UV ou RMN (proton ou carbone). Ces agents sont généralement non volatils, acides et polaires. Bien que certains composés inorganiques interviennent parfois, la majeure partie de la génotoxicité est attribuée aux agents organohalogénés (bromés ou/et chlorés), les principaux étant les trihalométhanes, acides acétiques, acétonitriles, cétones, et hydroxyfuranones. La fixation de normes contribue à limiter l'exposition des populations aux agents potentiellement dangereux. La qualité des eaux de boisson peut être accrue en utilisant une eau brute moins chargée en matière organique, et en améliorant le traitement chimique tout en veillant à conserver la qualité microbiologique de l'eau produite.
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Bouanga, F., J. de Laat, and M. Doré. "Mode D'elimination de composes organiques polaires par une alumine activee γ‐Al2O3en milieu aqueux. Comparaison avec le charbon actif." Environmental Technology Letters 7, no. 1-12 (January 1986): 239–54. http://dx.doi.org/10.1080/09593338609384409.
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Ben Haj Amara, A., J. Ben Brahim, G. Besson, and C. H. Pons. "Etude d'une nacrite intercalée par du dimethylsulfoxide et n-methylacetamide." Clay Minerals 30, no. 4 (December 1995): 295–306. http://dx.doi.org/10.1180/claymin.1995.030.4.03.
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ResumeUne nacrite est intercalée par deux composés organiques polaires: le diméthylsulfoxide (DMSO) et le n-méthylacétamide (NMA). Les deux solvants ont des moments dipolaires très voisins (4 debyes) mais des constantes diélectriques différentes (49 pour le DMSO et 179 pour le NMA). L'intercalation du NMA est plus rapide que celle du DMSO. Les deux complexes homogènes obtenus sont étudiés par diffraction des rayons X, spectroscopie infrarouge et ATD. L'étude par spectroscopie IR a montré que la nacrite expansée par du DMSO se comporte comme la kaolinite expansée par le même solvant. Dans le cas de la nacrite intercalée par du NMA, trois nouvelles bandes d'absorption dues aux vibrations de valence des OH liés par pont hydrogène avec le groupement C=O et situées respectivement à 3500, 3543 et 3589 cm−1 apparaissent. La fréquence v(N-H) du NMA est intermédiaire entre celles du liquide et d'une solution diluée, indiquant une liaison par pont hydrogène probablement avec les oxygènes de la couche tétraédrique du silicate. La diffraction des rayons X sur des échantillons orientés nous a permis d'obtenir 13 réflexions 00l pour chaque complexe. Une étude quantitative, par transformée de Fourier monodimensionnelle dans la direction perpendiculaire au plan du feuillet, a permis de déterminer le nombre de molécules organiques intercalées (une molécule par Si2Al2O5(OH)4) et leur orientation dans l'espace interlamellaire. L'ATD a montré par ailleurs que le complexe Nac.DMSO est plus stable que le complexe Nac.NMA.
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Sève, Michèle A. De, and Maxwell J. Dunbar. "Structure and Composition of Ice Algal Assemblages from the Gulf of St. Lawrence, Magdalen Islands Area." Canadian Journal of Fisheries and Aquatic Sciences 47, no. 4 (April 1, 1990): 780–88. http://dx.doi.org/10.1139/f90-090.
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Two types of ice algal assemblages were found in the Gulf of St. Lawrence: assemblages composed predominantly of pennate diatoms (abundance > 98.0%) and assemblages with a high abundance of centric diatoms (abundance > 46.2%). The first type is similar to Arctic landfast ice algal assemblages with the pennate diatoms Nitzschia cylindrus, N. polaris, and Navicula kariana as dominant species. The second type is similar to drifting ice algal assemblages previously described from the Gulf of St. Lawrence, with a percentage of centric diatom species > 46.2% due to the dominance of the planktonic diatom Thalassiosira nordenskioeldii. Species richness and the Shannon-Weaver index of diversity were low; density ranged from 104–106 × cells∙L−1 and was negatively correlated with percent centric diatoms. Results on the structure and the composition of the ice algal assemblages are related to ice type, i.e. landfast and drifting pack ice, and compared with ice algal assemblages from higher latitudes.
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Goldstein, Bob, and Jeremy Nance. "Caenorhabditis elegans Gastrulation: A Model for Understanding How Cells Polarize, Change Shape, and Journey Toward the Center of an Embryo." Genetics 214, no. 2 (February 2020): 265–77. http://dx.doi.org/10.1534/genetics.119.300240.
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Gastrulation is fundamental to the development of multicellular animals. Along with neurulation, gastrulation is one of the major processes of morphogenesis in which cells or whole tissues move from the surface of an embryo to its interior. Cell internalization mechanisms that have been discovered to date in Caenorhabditis elegans gastrulation bear some similarity to internalization mechanisms of other systems including Drosophila, Xenopus, and mouse, suggesting that ancient and conserved mechanisms internalize cells in diverse organisms. C. elegans gastrulation occurs at an early stage, beginning when the embryo is composed of just 26 cells, suggesting some promise for connecting the rich array of developmental mechanisms that establish polarity and pattern in embryos to the force-producing mechanisms that change cell shapes and move cells interiorly. Here, we review our current understanding of C. elegans gastrulation mechanisms. We address how cells determine which direction is the interior and polarize with respect to that direction, how cells change shape by apical constriction and internalize, and how the embryo specifies which cells will internalize and when. We summarize future prospects for using this system to discover some of the general principles by which animal cells change shape and internalize during development.
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Peng, Yongtao, Dan Xu, Yaya Li, and Kun Wang. "A Product Service Supply Chain Network Equilibrium Model considering Capacity Constraints." Mathematical Problems in Engineering 2020 (November 16, 2020): 1–15. http://dx.doi.org/10.1155/2020/1295072.
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With the further development of manufacturing servitization, the supply chain established by enterprises has gradually evolved into a product service supply chain. The introduction of service flow has made supply chain management more complicated. In this paper, we build a product service supply chain network composed of raw material suppliers, service providers, manufacturing integrators, and customers. The equilibrium model for decision-makers at all levels is established by variational inequality. In particular, we emphasize the impact of product and service capacity constraints and changes in the product service integration ratio on network equilibrium. The results show that, while capacity constraints on production tend to stabilize and unify the market price, service-related capacity constraints polarize the customer pay price. That is to say, product capability constraints limit the quality of product service systems, while service capability constraints limit the types of product service systems. Furthermore, the introduction of service flow and integration with products creates a more closely networked relationship between the upper and lower layers of the product service supply chain, and an increase in the service proportion will increase the network equilibrium profit.
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Zinkl, G. M., A. Zuk, P. van der Bijl, G. van Meer, and K. S. Matlin. "An antiglycolipid antibody inhibits Madin-Darby canine kidney cell adhesion to laminin and interferes with basolateral polarization and tight junction formation." Journal of Cell Biology 133, no. 3 (May 1, 1996): 695–708. http://dx.doi.org/10.1083/jcb.133.3.695.
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Epithelial cells polarize not only in response to cell-cell contacts, but also to contacts with a substratum composed of extracellular matrix molecules. To probe the role of specific matrix constituents in epithelial cell polarization, we investigated the effects of an adhesion-blocking mAb, 12B12, on initial polarization of MDCK cells. The 12B12 antibody, raised against whole MDCK cells, blocks adhesion to laminin by 65% but has no effect on adhesion of cells to collagen type I. Taking advantage of this antibody's function-blocking activity, as well as the fact that MDCK cells secrete laminin, the role of endogenous laminin in polarization was examined by plating cells on collagen-coated substrata in the presence of the antibody. Under these conditions, cell spreading was reduced 1.5h after plating, and cells were flatter and had fewer microvilli after 24 h. Even though lateral cell membranes were closely apposed, transepithelial resistance in the presence of the antibody was significantly reduced relative to controls. When the polarization of specific apical and basolateral markers was examined both biochemically and immunocytochemically in the presence of the antibody, we observed that the apical marker polarized at normal rates while basolateral markers did not. Surprisingly, the 12B12 antibody was not directed against any known cell adhesion protein but reacted specifically with Forssman antigen, a glycosphingolipid. These results suggest that glycolipids may play a significant role in cell adhesion via laminin and in epithelial cell polarization.
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Kovalenker, V. A., O. Yu Plotinskaya, C. J. Stanley, A. C. Roberts, A. M. McDonald, and M. A. Cooper. "Kurilite – Ag8Te3Se – a new mineral from the Prasolovskoe deposit, Kuril islands, Russian Federation." Mineralogical Magazine 74, no. 3 (June 2010): 463–68. http://dx.doi.org/10.1180/minmag.2010.074.3.463.
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AbstractKurilite, with the simplified formula, Ag8Te3Se, is a new mineral from the Prasolovskoe epithermal Au-Ag deposit, Kunashir Island, Kuril arc, Russian Federation. It occurs as aggregates up to 2 mm in size, composed of brittle xenomorphic grains, up to several μm in size, in quartz, associated with tetrahedrite, hessite, sylvanite and petzite. Kurilite is opaque, grey, with a metallic lustre and a black streak. Under plane-polarized light, kurilite is white with no observed bireflectance, cleavage, or parting observed. Under crossed polars it appears isotropic without internal reflections. Reflectance values in air and in oil, are tabulated. It has a mean VHN (25 g load) of 99.9 kg/mm2 which equates roughly to a Mohs hardness of 3. Electron microprobe analyses yield a mean composition of Ag 63.71, Au 0.29, Te 29.48, Se 5.04, S 0.07, total 98.71 wt.%. The empirical formula (based on 12 atoms) is (Ag7.97Au0.02)Σ7.99Te3.00(Se0.86Te0.12S0.03)Σ1.01. The calculated density is 7.799 g/cm3 (based on the empirical formula and unit-cell parameters refined from single-crystal data). Kurilite is rhombohedral, R3 or , a 15.80(1), c 19.57(6) Å, V 4231(12)Å3, c:a 1.2386, Z = 15. Its crystal structure remains unsolved. The seven strongest lines of the X-ray powder-diffraction pattern [d in Å (I)(hkl)] are: 3.727(20)(131), 2.996(50)(232), 2.510(30)(226,422), 2.201(100)(128,416,342), 2.152(20)(603), 2.079(30)(253), 2.046(20)(336,434). The mineral is named after the locality.
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Ongas, Martin, Joseph Standing, Bernhards Ogutu, Joseph Waichungo, James A. Berkley, and Karin Kipper. "Liquid chromatography–tandem mass spectrometry for the simultaneous quantitation of ceftriaxone, metronidazole and hydroxymetronidazole in plasma from seriously ill, severely malnourished children." Wellcome Open Research 2 (June 19, 2017): 43. http://dx.doi.org/10.12688/wellcomeopenres.11728.1.
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We have developed and validated a novel, sensitive, selective and reproducible reversed-phase high-performance liquid chromatography method coupled with electrospray ionization mass spectrometry (HPLC–ESI-MS/MS) for the simultaneous quantitation of ceftriaxone (CEF), metronidazole (MET) and hydroxymetronidazole (MET-OH) from only 50 µL of human plasma, and unbound CEF from 25 µL plasma ultra-filtrate to evaluate the effect of protein binding. Cefuroxime axetil (CEFU) was used as an internal standard (IS). The analytes were extracted by a protein precipitation procedure with acetonitrile and separated on a reversed-phase Polaris 5 C18-Analytical column using a mobile phase composed of acetonitrile containing 0.1% (v/v) formic acid and 10 mM aqueous ammonium formate pH 2.5, delivered at a flow-rate of 300 µL/min. Multiple reaction monitoring was performed in the positive ion mode using the transitions m/z555.1→m/z396.0 (CEF), m/z172.2→m/z 128.2 (MET), m/z188.0→m/z125.9 (MET-OH) and m/z528.1→m/z 364.0 (CEFU) to quantify the drugs. Calibration curves in spiked plasma and ultra-filtrate were linear (r2 ≥ 0.9948) from 0.4–300 µg/mL for CEF, 0.05–50 µg/mL for MET and 0.02 – 30 µg/mL for MET-OH. The intra- and inter- assay precisions were less than 9% and the mean extraction recoveries were 94.0% (CEF), 98.2% (MET), 99.6% (MET-OH) and 104.6% (CEF in ultra-filtrate); the recoveries for the IS were 93.8% (in plasma) and 97.6% (in ultra-filtrate). The validated method was successfully applied to a pharmacokinetic study of CEF, MET and MET-OH in hospitalized children with complicated severe acute malnutrition following an oral administration of MET and intravenous administration of CEF over the course of 72 hours.
Dissertations / Theses on the topic "Composé polaire"
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Jaumouillé, Valentin. "Aspects cellulaires et moléculaires de la sécrétion d'IpaC, un effecteur et composé du translocateur du système de sécrétion de type III chez Shigella flexneri." Paris 6, 2008. http://www.theses.fr/2008PA066318.
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Shigella, l’agent de la dysenterie bacillaire, utilise un système de sécrétion de type III (T3SS) pour envahir et détruire les cellules de l’épithélium recto-colique. Le T3SS est activé par le contact cellulaire. Les protéines IpaC et IpaB sont sécrétées et s’insèrent dans la membrane de la cellule hôte pour former un translocateur, requis pour l’injection des effecteurs du T3SS. Nous avons montré qu’IpaC est stockée puis sécrétée à un pôle de la bactérie. Cette localisation polaire dirige l’injection des effecteurs lors de l’invasion. IpaC se juxtapose à IcsA, au nouveau ou au vieux pôle. La localisation d’IpaC est indépendante du T3SS. Les régions d’IpaC impliquées dans sa localisation ont été caractérisées. La polarisation d’IpaC conditionne l’efficacité de sa sécrétion. En utilisant une fusion IpaC-CFP qui bloque le T3SS, nous avons mis en évidence un contrôle commun de la sécrétion d’IpaC et IpaB. IpaC s’associe à la base du T3SS, probablement en complexe avec IpaB. In vitro, IpaC est reconnue par l’ATPase du T3SS. Le complexe formé par les composés du translocateur à la base du T3SS pourrait conditionner leur assemblage dans la membrane de la cellule hôte.
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Mansuy-Huault, Laurence. "Rôle du milieu réactionnel au cours de la maturation artificielle de la matière organique : application au prélèvement des effluents en cours de pyrolyse." Vandoeuvre-les-Nancy, INPL, 1995. http://www.theses.fr/1995INPL041N.
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Dans un système de pyrolyse comme dans un système de maturation naturelle de la matière organique, les différentes fractions du pyrolysat, qui constituent le milieu réactionnel, sont en contact intime sous l'effet de la pression développée dans le système. De façon à mettre en évidence les interactions entre ces différentes fractions et leur importance dans les réactions de maturation de la matière organique, cinq milieux réactionnels différents ont été reconstitués (1) une série de pyrolyse en milieu confiné classique du charbon de la Mahakam (280°C à 370°C - 24 h ; 700 bars) (2) une série EC où les hydrocarbures et les composés polaires sont prélevés à chaque étape de pyrolyse (étude du résidu solide au cours de la maturation) (3) une série EP ou le résidu solide et les composés polaires sont préservés dans le milieu tandis que les hydrocarbures sont prélevés (4, 5) l'influence d'un excès d'eau sur le comportement du résidu solide et de l'ensemble résidu solide-composés polaires est étudiée dans les séries ECO et EPO. Les résultats montrent l'importance des hydrocarbures dans les réactions de maturation du charbon. Ils jouent le role de phase mobile dans le milieu réactionnel et favorisent la mobilité des espèces, le transfert d'hydrogène et la plasticité du charbon. L’eau a aussi un rôle actif dans les processus de genèse des hydrocarbures mais sont rôle de source d'hydrogène dépend de la présence des composés polaires qui pourrait être les catalyseurs de la dissociation de l'eau
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Vialatte, Anne. "Effets des entrées énergétiques sur les composés azotés dans la haute atmosphère de la Terre." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAY066/document.
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La météorologie de l’espace est un domaine dédié à l’étude de l’impact des variations de l’activité solaire sur l’environnement spatial de la Terre. Celles-ci peuvent avoir des conséquences importantes sur les technologies humaines, comme les réseaux de lignes haute-tension ou les systèmes de télécommunication par satellites. Ces mêmes variations sont également à l’origine des aurores, phénomènes observés dans la haute atmosphère de la Terre au niveau des pôles, au pied des lignes de champ magnétique. Elles vont pouvoir nous servir de traceur dans l’étude des particules so- laires piégées dans l’environnement spatial de notre planète.Les émissions aurorales, complexes, de part leur étalement et différen- ciation en altitude et de leur diversité spectrale, restent un challenge ob- servationnel.Les émissions atomiques aurorales sont bien documentées, mais ce n’est pas toujours le cas des émissions moléculaires, qui sont pourtant une source d’information potentielle sur les précipitations énergétiques prove- nant de la magnétosphère. C’est dans ce contexte que se place la définition de la mission du nanosatellite ATISE (Auroral Thermospheric and Ionosphe- ric Spectrometer Experiment), développé au Centre Spatial Universitaire de Grenoble. Il aura pour but l’observation de la haute atmosphère terrestre via l’acquisition de spectres dans le proche UV et le visible.Le diazote N2 et son ion N2+ font partie des composés majoritaires de l’atmosphère, et sont donc un choix cohérent afin de définir l’observabilité des émissions moléculaires. Le monoxyde d’azote NO est une espèce mino- ritaire dans la thermosphère, mais va avoir un rôle clé dans la destruction d’ozone stratosphérique, et donc dans la problématique du dérèglement climatique.Les émissions de ces composés, et notamment leurs profils verticaux ainsi que intensités ont été étudiées grâce au modèle TRANS, qui résout l’équation de Boltzmann pour le transport d’électrons. Ceci nous a aidé à caractériser les besoins scientifiques de la mission ATISE. Dans un second temps, l’analyse des résultats du démonstrateur-sol de ce nanosatellite a montré le potentiel de cette mission, bien que certaines spécifications ne soient pas encore atteintes. Enfin, toujours dans cette logique de recherche de nouvelles quantités observables pour la météorologie de l’espace, une dernière partie abordera la polarisation de la lumière aurorale, avec l’étude de la bande à 427,8 nm de N2+Space weather is the study of the Solar activity’s impact on Earth’s space environment. This is relevant as it may have serious consequences over modern technology, such as high-voltage power lines grids or telecommu- nication systems via satellites. Solar activity is also the phenomenon that causes the aurorae, which can be seen in Earth’s upper atmosphere, at the poles, at the base of magnetic field lines. Due to this aurorae may be used as a proxy for the study of Solar particles trapped in Earth’s magnetic field.Auroral emissions are complex, as they are spread over various altitudes and wide spectral ranges. Therefore, they remain an observational chal- lenge.Emissions from atomic lines transitions in aurorae are well documented and understood, but this is not always the case for molecular emissions. These are a potential source of information on energetic inputs from the magnetosphere. This is the context in which the ATISE (Auroral Thermo- spheric and Ionospheric Spectrometer Experiment) nanosatellite was designed in the Grenoble University Space Center. Its purpose will be to observe Earth’s upper atmosphere through the acquisition of spectra in near-UV and visible domains.Dinitrogen N2 and its ion N2+ are major components of Earth’s atmos- phere at larges altitudes, and therefore a logical choice in order to define molecular emission observability. On the other hand, nitrogen monoxide NO is a minor component in the thermosphere, but has a key role in stra- tospheric ozone destruction, and therefore has important consequences on the climate.Auroral emissions, and more particularly their vertical profiles and in- tensities were studied with the TRANS model, which solves the Boltzmann equation for electron transport in the atmosphere. We used these results to define the scientific requisites for the ATISE mission. In a second phase, we tested and analyzed the results of a ground demonstrator of the instru- mentation that will be found in the nanosatellite. It showed great potential, despite the fact that part of the specifications are not yet fulfilled. Finally, still looking for new observables quantities for space weather, we studied the polarisation of auroral light, with a focus on the 427,8 nm band of N2+
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Vidoni, Olivia. "Synthèse et approche de la réactivité catalytique de nanoparticules métalliques en milieu organique polaire." Toulouse 3, 1999. http://www.theses.fr/1999TOU30233.
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Millot, Claude. "Simulation par dynamique moléculaire de liquides composés de molécules polaires et déformables." Nancy 1, 1990. http://www.theses.fr/1990NAN10037.
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Ce mémoire est consacré à l'étude par simulation de dynamique moléculaire de quelques liquides simples composés de molécules polaires et déformables. Dans une première partie, le principe des méthodes de simulation de dynamique moléculaire est exposé et les algorithmes utilisés dans ce travail sont décrits. Dans une seconde partie, les résultats d'une série de simulations d'un modèle simple de chlorure de méthyle en phase liquide en fonction de la température et de la densité sont présentés, la troisième partie décrit une simulation de l'équilibre conformationnel gauche-trans d'un modèle de n-butane. La dernière partie est consacrée à l'étude de l'équilibre conformationnel d'un modèle de 1,2-dichloroéthane. L'accent est mis sur l'effet des intéractions électrostatiques sur les propriétés statiques et dynamiques du système
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Rivière, Emmanuel. "Modélisation physico-chimique de la stratosphère arctique : études des nuages stratosphériques polaires et des interactions entre composés halogénés et composés azotés." Orléans, 2001. http://www.theses.fr/2001ORLE2054.
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Le travail présenté dans ce document s'inscrit dans le contexte de la diminution de l'ozone stratosphérique observée en région polaire, encore mal quantifiée par les modèles. Dans ce contexte général, nous nous focalisons sur deux processus importants de la stratosphère polaire : l'étude des nuages stratosphériques polaires (PSC), et celle des interactions entre composés halogénés et composés azotés. Pour se faire, le modèle lagrangien MiPLaSMO a été développé. Il contient un module détaillé de PSC, un module de chimie et un module de trajectoire. Concernant les PSC, les théories récentes de formation des nuages concernant le seuil de surfusion des particules liquides et la congélation en glace ont été validées. Nous avons également confirmé la nécessité de prendre en compte des ondes de montagne pour interpréter les mesures microphysiques en Arctique. L'impact des PSC d'onde de montagne sur l'activation du chlore semble significative. Concernant l'étude des interactions entre composés halogénés et composés azotés, nous avons montré, pour tous les cas étudiés, une sous-estimation systématique de NO2 par le modèle. Parallèlement, un accord entre mesures et modélisation de OClO est observé en dessous de 21 km. Au-delà un accord est possible dans le vortex si l'on tient compte des incertitudes sur les réactions chimiques faisant intervenir les NOx. En outre, une grande sensibilité de OClO envers NO2 est mis en évidence, due à la réaction BrO + NO2. On montre que résoudre la sous-estimation de NO2 dans les modèles impliquerait une sous-estimation des composés halogénés actifs. Cela met en évidence que les interactions ClOx-NOx sont mal comprises. Un accord simultané de OClO et de NO2 est possible lorsque ces interactions n'ont pas lieu (situation dénoxifiée) ou si le brome est maintenu sous forme active quand le NO2 simulé est en accord avec la mesure. Ces résultats encouragent à effectuer d'autres mesures simultanées de Cly et de NOy.
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Arzel, Ludovic. "Signatures de la compétition des transitions polaire et distortive du titanate de strontium." Montpellier 2, 2001. http://www.theses.fr/2001MON20146.
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Belles, Angel. "Développement et applications environnementales des échantillonneurs passifs pour la surveillance des écosystèmes aquatiques." Thesis, Bordeaux 1, 2012. http://www.theses.fr/2012BOR14723/document.
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Pour une meilleure compréhension en gestion de la qualité de l’environnement le dosage des contaminants dans les différents compartiments naturels reste un premier pas vers l’élucidation de la dynamique des polluants et de leurs impacts sur les écosystèmes. Cependant les stratégies d’échantillonnage usuellement utilisées n’ont pas changé depuis l’avènement de la chimie analytique. Ces techniques consistent en général à prélever une certaine quantité de l’échantillon (eau, air, solide) afin d’en extraire les substances d’intérêt pour les doser. La question de la représentativité de telles pratiques se pose alors ; en effet pour un site donné la contamination peut être très variable au cours du temps et sur de faibles distances. La compréhension fine de la contamination d’un milieu en utilisant de telles techniques impose alors la multiplication des prélèvements dans le temps et l’espace.Depuis les années 80 mais surtout depuis le début des années 2000, des outils d’échantillonnage passif ont été mis au point dans de nombreux domaines permettant d’avoir un suivi de la contamination intégré dans le temps à moindre coût. Ces nouvelles approches consistent à prélever l’échantillon en continu et in-situ sans apport d’énergie, fournissant ainsi une valeur moyenne de la contamination.Afin de pouvoir utiliser ces dispositifs, un certain nombre de développements en laboratoire doivent être au préalable menés afin de déterminer les constantes cinétiques nécessaires pour déduire la contamination du milieu échantillonné à partir des résidus séquestrés par les échantillonneurs. Ainsi, dans le cadre de ces travaux, une sélection d’échantillonneurs existants ont été testés et adaptés en laboratoire puis évalués en conditions réelles sur divers sites environnementaux.Les développements en laboratoire ont eu pour objet de mettre au point différentes configurations d’outils dans le but d’être applicables au plus grand nombre de molécules et ce de la manière la plus quantitative possible. A titre d’exemple, des dispositifs adaptés ont été mis au point pour l’échantillonnage de molécules très polaires qui auparavant n’étaient pas efficacement échantillonnées par les dispositifs existants. Sur site, les outils d’échantillonnage ont principalement été mis en œuvre dans le cadre de programmes de recherche plus vastes et ont à ce titre pu être testés sur de grands terrains d’étude (Bassin d’Arcachon et Estuaire de la Gironde) et être comparés aux techniques d’échantillonnage ponctuels qui font actuellement référence. Les résultats fournis par les outils sont proches de ceux obtenus par échantillonnage ponctuel. Cependant l’aspect quantitatif apparaît probablement encore améliorable soit par l’usage de nouveaux composés référence de performance soit par mise au point de dispositifs plus robustes et faiblement impactés dans leurs performances par les conditions environnementalesFor a better understanding and management of the environmental quality, contaminant analysis in the various compartments is a natural first step in the understanding of the dynamics of pollutants and of their impacts on ecosystems. However sampling strategies commonly used have not changed since the advent of analytical chemistry. These techniques in general consist of taking a certain amount of sample (water, air, solid) to extract the substances of interest to assay. The issue of representativeness of such sampling practices arises since for a given site the contamination can vary over time and over short distances. Detailed understanding of the contamination of an ecosystem using such sampling techniques requires the multiplication of samples over time and space.Since the 80’s and more especially the beginning of 2000, passive sampling tools have been developed in many areas. They provide an integrated monitoring of contamination over time at low cost. These new approaches are based on the fact that the sample are taken continuously in-situ and without energy supply, thus providing an average value of the contamination.To use these devices, a number of laboratory developments must first be conducted to determine the kinetic constants to deduce the necessary characteristics of the environmental contamination. Thus, as part of this work, a selection of existing samplers has been tested and adapted in laboratory experiments and evaluated in real conditions at various environmental sites.Laboratory developments have been conducted to develop different configuration tools in order to be used for a wide range of pollutants with the best quantitative capacity. For example, suitable devices have been developed for sampling highly polar molecules which previously were not strongly sampled by existing devices.On-site, sampling tools were mainly implemented in the framework of broader research programs and consequently have been tested during large field studies (Bassin d'Arcachon, Gironde Estuary) to compare their performance to grab sampling techniques. The results provided by the tools are similar to those obtained by grab sampling. However, the quantitative aspect appears still improvable either by the use of new performance reference compounds or by using devices more robust and slightly affected in their performance by environmental conditions
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Marchal, Jérôme. "Contrôle de la réactivité en polymérisation anionique de monomères vinyliques polaires par des composés azotés." Bordeaux 1, 1998. http://www.theses.fr/1998BOR10517.
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L'etude conduite porte sur l'utilisation de ligands azotes dans le but d'obtenir des polymerisations anioniques vivantes et/ou controlees de monomeres vinyliques polaires. Dans une premiere partie, des multiamines tertiaires ont ete utilisees en tant que complexant et une diminution de la reactivite intrinseque des especes actives a pu etre mise en evidence. Parmi toutes les multiamines tertiaires testees, la sparteine et la pentamethyldiethylenetriamine se sont averees les meilleurs agents complexants en terme de controle de la polymerisation du methacrylate de methyle (mma). Les effets benefiques de ces additifs sur la reactivite d'especes de type enolate lithies ont ete exploites pour preparer des polymethacrylates de methyle (pmma) de structure controlee a temperature ambiante, mais aussi pour synthetiser des pmma -hydroxyles. La diminution de la reactivite a ete demontree d'un point de vue cinetique par la mesure des constantes de vitesse de propagation et de terminaison dans un reacteur tubulaire specialement concu pour les polymerisations rapides. Parallelement, la calorimetrie adiabatique a ete utilisee a des fins cinetiques avec la 2-vinylpyridine (monomere modele). La deuxieme partie de l'etude porte sur la synthese de pmma effectuee en presence de nouveaux ligands - de l'espece en croissance a savoir les aminoalcoolates de lithium. Il a ete montre que l'un de ces ligands, le 2-(dimethylamino-)ethanolate de lithium, est un agent complexant tres efficace pour empecher les reactions secondaires de terminaison propre a la polymerisation anionique du mma. Il apparait que le rapport ligand/amorceur, la polarite du solvant, la temperature, les concentrations en centres actifs et en amorceur sont les parametres clefs pour le controle du processus de polymerisation.
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Duez, Valérie. "Hétérostructures semiconductrices uni-et bi-polaires : de la physique au composant." Lille 1, 2000. https://pepite-depot.univ-lille.fr/RESTREINT/Th_Num/2000/50376-2000-186.pdf.
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Ce memoire est consacre a l'etude des heterostructures formees a partir de materiaux semiconducteurs iii-v appliquees aux dispositifs electroniques quantiques. Trois themes sont plus particulierement abordes. Leur denominateur commun est la simulation des proprietes physiques des heterostructures tant d'un point de vue electrique qu'optique mettant en jeu la resolution autocoherente des equations de poisson et de schrodinger mono-et multi-bandes. Nous avons tout d'abord etudie l'heterostructure inalas/inp, intrinsequement de type ii. L'analyse des spectres de photoluminescence nous a amene a considerer les readaptations d'interface favorisant l'apparition d'une couche intermediaire d'inas qui transforme l'heterostructure en un type mixte type i/type ii. Ensuite nous abordons la multiplication de frequence avec les composants hbv (heterostructure barrier varactor) dont les proprietes de symetrie favorisent la generation d'harmoniques impairs. La non-linearite capacitive a ete optimisee dans les systemes de materiaux inp et gaas par insertion de perturbations de potentiel de part et d'autre de la barriere bloquante. Des contrastes de capacite proches de 10 : 1 associes a des tensions de seuil elevees ont ete obtenus. Des criteres de conception pour un fonctionnement vers les frequences terahertz sont proposes. Enfin nous presentons une etude de la diode a effet tunnel resonnant interbande par une approche multibande. En effet ce type de composant a base d'antimoine favorise un courant electrons-trous legers-electrons dont l'allure est modulee par la reaction de charge d'espace des trous lourds. Ceci est mis a profit pour l'analyse de detecteurs optiques ultra-rapides a haute sensibilite.
Books on the topic "Composé polaire"
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Pullman, Philip. The Golden Compass (His Dark Materials, Book 1). Books On Tape, 2000.
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Pullman, Philip. The Golden Compass (His Dark Materials, Book 1). Del Rey Books, 1998.
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Pullman, Philip. The Golden Compass (His Dark Materials, Book 1). Listening Library, 1999.
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Pullman, Philip. The Golden Compass (His Dark Materials, Book 1). Books on Tape, Inc., 1997.
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Pullman, Philip. The Golden Compass (His Dark Materials, Book 1). Ballantine Books, 1999.
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Pullman, Philip. The Golden Compass (His Dark Materials, Book 1). Knopf Books for Young Readers, 2002.
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(US), National Research Council, Space Studies Board, and Committee on Earth Studies. Issues in the Integration of Research and Operational Satellite Systems for Climate Research: Part II. Implementation (Compass Series (Washington, D.C.).). National Academies Press, 2001.
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(US), National Research Council. Issues in the Integration of Research and Operationsl Satellite Systems for Climate Research: Science and Design (Compass Series (Washington, D.C.).). National Academy Press, 2000.
Find full textBook chapters on the topic "Composé polaire"
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Lyapustina, S. A., H. L. Clercq, J. H. Hendricks, S. T. Arnold, J. G. Eaton, H. S. Sarkas, T. P. Lippa, et al. "Excess Electron Clusters Composed of Polar, Hydrogen Bond-Forming Molecules: Negative Ion Photoelectron Spectroscopic Studies." In Recent Theoretical and Experimental Advances in Hydrogen Bonded Clusters, 339–43. Dordrecht: Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-015-9434-9_23.
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Yung, Yuk L., and William B. DeMore. "Jovian Planets." In Photochemistry of Planetary Atmospheres. Oxford University Press, 1999. http://dx.doi.org/10.1093/oso/9780195105018.003.0008.
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The four giant planets in the outer solar system, Jupiter, Saturn, Uranus, and Neptune, are a distinct group by themselves. The essential astronomical and atmospheric aspects of these planets are summarized in table 5.1. The significance of this group in the chemistry of the solar system is briefly pointed out in chapter 4. These planets are composed primarily of the lightest elements, hydrogen and helium, which were captured from the solar nebula during formation. The planets have rocky cores made of heavier elements. In the case of Jupiter and Saturn the mass of the gas greatly exceeds that of the core, whereas for Uranus and Neptune the masses of gas and core are comparable. Due to the enormous gravity of the giant planets, little mass has escaped from their atmospheres. Hence, the bulk composition of these planets provides a good measure of the initial composition of the solar nebula from which they were derived. Of all planetary bodies in the solar system, the constituents of giant planets are the closest to the cosmic abundances of the elements. The chemistry of the atmospheres of the giant planets is interesting for the following reasons:… 1. chemistry in a dominantly reducing atmosphere 2. interplay between photochemistry and equilibrium chemistry 3. ion chemistry in polar auroral regions 4. heterogeneous chemistry of aerosols 5. chemistry of meteoritic debris 6. lack of a planetary "surface"… We briefly comment on these reasons in this section. Each topic will receive a more detailed treatment in later sections. First of all, the atmospheres of the Jovian planets are more than 90% hydrogen and helium. Since helium is inert, the atmospheric chemistry is dominated by hydrogen. Therefore, we would expect the most stable compounds of carbon, oxygen, nitrogen, and phosphorus to be CH4, H2O, NHa, and PHs. This is in fact confirmed by the available observed composition of the bulk atmospheres of these planets. However, in the upper atmospheres of these planets, the composition is controlled by photochemistry.
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Yung, Yuk L., and William B. DeMore. "Mars." In Photochemistry of Planetary Atmospheres. Oxford University Press, 1999. http://dx.doi.org/10.1093/oso/9780195105018.003.0010.
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Mars has been extensively studied by a series of spacecraft since the dawn of the space age: by Mariners 4, 6, 7, and 9 (1965-1972), Mars 2 through 6 (1971-1974), and the two Viking Landers and Orbiters in 1976. The knowledge from spacecraft is supplemented by ground-based observations. The essential aspects of Mars are summarized in table 7.1. It is a smaller planet than Earth; the radius and mass are, respectively, 53% and 11% of Earth. The surface gravity is 3.71 m s~2, compared with the terrestrial value of 9.82 m s~2. The physical properties and composition of the Martian atmosphere are summarized in tables 7.1 and 7.2; isotopic composition is given in table 7.3. An example of how this knowledge is obtained is illustrated in figure 7.1, showing the mass spectrum obtained by the mass spectrometer experiment on Viking. The bulk atmosphere is composed of CO2, with small amounts of N2 and Ar and a trace amount of water vapor. Located at 1.52 AU from the sun, the mean insolation at Mars is about half that of Earth. As a result, it is a colder planet, with mean surface temperature of 220 K, too cold for water to flow on the surface in the current epoch. The lack of an ocean results in an arid and dusty climate. The obliquity of Mars is 25.2°, close to the terrestrial value of 23.5°; however, Mars has an eccentric orbit, with eccentricity of 0.093. The ratio of incident solar radiation at perihelion to aphelion is 1.45. The large seasonal variation in heating is believed to be responsible for the spectacular global dust storms that can be observed from Earth and have inspired imaginative but erroneous theories about their origin. The polar regions of Mars can be as cold as 125 K, so CO2 will condense as frost on the surface. In fact, according to the Leighton-Murray model, this is what determines the pressure of the atmosphere. Figure 7.2 shows the seasonal pressure variations at the Viking lander sites for 3.3 Mars years from 1976. Note that the magnitude of the pressure changes is of the order of 20%, compared to the maximum change of 1% on the surface of Earth.
Conference papers on the topic "Composé polaire"
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Larciprete, Maria Cristina, Marco Centini, Concita Sibilia, and Roberto Li Voti. "Tuning thermal emission in metamaterials composed by oriented polar inclusions." In Metamaterials, edited by Allan D. Boardman, Kevin F. MacDonald, and Anatoly V. Zayats. SPIE, 2018. http://dx.doi.org/10.1117/12.2307379.
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Tanaka, Yuya, Noritaka Matsuura, Yuki Tazo, Hideyuki Kayaguchi, and Hisao Ishii. "Electret-based vibrational energy generator composed of polar molecules for OLED." In 2021 28th International Workshop on Active-Matrix Flatpanel Displays and Devices (AM-FPD). IEEE, 2021. http://dx.doi.org/10.23919/am-fpd52126.2021.9499201.
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Purwar, Anurag, and Qiaode Jeffrey Ge. "Reconciling Distance Metric Methods for Rigid Body Displacements." In ASME 2009 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/detc2009-87718.
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In the last twenty years, researchers have proposed a few different methods to establish a norm (or, metric) for both planar and spatial rigid body displacements. Desire to meaningfully quantify a displacement composed of rotation and translation stems from a requirement to ascertain “distance” between two given displacements in applications, such as motion approximation and interpolation, mechanism synthesis, collision avoidance, positioning, and robot calibration and control. In this paper, we show that the various seemingly different shape independent norm calculation methods based on approximating displacements with higher dimensional rotations via orthogonal matrices, or polar decomposition (PD) and singular value decomposition (SVD) can be reconciled and unified in the mathematically compact and elegant framework of biquaternions. In the process, we also propose an elegant and fast method for such norm calculations.
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Wang, Youzhen, Guoqing Feng, and Pengfei Li. "Research on Monitoring Point Layout of Health Monitoring System of the Icebreaker." In ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/omae2017-62491.
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As one kind of special ship, polar Ice-breaking ships are used to break the ice for other ships or for researchers going deeper to the polar region. The safety of Ice-breaking ships should be emphasized not only because of it special shape but also because of its unique load case and complex marine environment. Structure Health Monitoring (SHM) should be installed in them owing to reasons mentioned above, even if there are rules that had been used while designing the ships. How to choose appropriate monitoring points is one of the most important things in this whole project. For providing more rational approach to selecting measure points in Structure Health Monitoring by FEM analysis, two methods were proposed and compared in order to determine a better one which can reduce the workload. One of these two methods is design wave approach which can show ultimate strength but just in the case of hogging, sagging and other typical cases, which ignore a large number of cases the ship may meet. The other one is composed of 240 structural responses from 20 kinds of frequencies in 12 directions (Data of spectral analysis), and weighted mean value based on ocean wave spectrum would be seen as an assessment of the damage caused by natural environment. For huge data in the finite element analysis, there must be a set of feasible algorithms to automatically process the results to get monitoring points. After that the monitoring point can be and stress measured by fiber-optic sensor at that point will be monitored in real time.
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Tierno, Nicholas, Nicholas White, and Mario Garcia-Sanz. "Longitudinal Flight Control for a Novel Airborne Wind Energy System: Robust MIMO Control Design Techniques." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-64516.
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This paper deals with the longitudinal flight control for a novel Airborne Wind Energy (AWE) system: the EAGLE System. It is a tethered lighter-than-air flyer wind turbine composed of a blimp, several aerodynamic airfoils (wings) with specific aerodynamic control surfaces (ailerons, elevator, rudder), a counter-rotating aerodynamic rotor for the wind turbine (four identical sections, symmetrically arranged, with three blades each), an electrical synchronous generator attached to the counter-rotating rotors, and a tether to secure the airship and to transmit the generated power. Additional information can be found in US Patent, Provisional Application No. 61/387,432 developed by the authors. The designed system proposed here supports a 2.5 kW generator and flies at approximately 100 meters. The mathematical model developed for the AWE system incorporates a hybrid blimp-airfoil design, modeled using a hybrid Cartesian-polar coordinate system to capture the dynamics of both the airship and the tether, and includes the effect of the counter-rotating aerodynamic rotor of the wind turbine, as well as the aerodynamic control surfaces. This paper presents the design of a robust Multi-Input Multi-Output (MIMO) controller for the 3×3 longitudinal flight dynamics of the tethered airborne wind energy system. The control system is designed by applying sequential MIMO robust Quantitative Feedback Theory (QFT) techniques.
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Nguyen, Khe C., Sinh T. Do, and Thong V. De. "Novel Proton Exchange Membrane Utilizing Nano Composite for Fuel Cell Application." In ASME 2006 Multifunctional Nanocomposites International Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/mn2006-17013.
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In the present report, we conducted the study of chemical top down process which seems to provide better efficiency and better cost saving than the physical top down in the fabrication of nano scale, especially, when applying to carbon materials. It is found that the chemical top down performs effectively with multiple attachments of electrolytic groups onto the surface of the carbon powder by diazo coupling reaction. As a result, we are able to isolate the nano scale of carbon particles with strong polar solvents such as water and believe that it is due to electrostatic repulsive force between same sign charges existing in the polarized electrolytic groups... The cleavage of azo bond in a naked carbon product can occur above 110oC in ambient condition but can also escape by a nano composite structure using specific emulsion polymer as binder matrix. Electrolytic groups carry charge from ionization are proven to reduce electron transport but enhance proton transport capability of carbon material, have successfully demonstrated a proton exchange membrane (PEM) which exhibits better heat resistance and higher current density than the commercial Nafion product in the PEM fuel cell application. The diazo coupling product of carbon exhibits a core-shell structure composed of a nano scale hydrophobic core and electrolytic shell, showing apparent “solubility” and named as “liquid” nano carbon (LNC).
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Rahman, Mosfequr, Gustavo Molina, Sirajus Salekeen, Ana Dungan, Isaac Hyers, Daniel Griffin, and Alexander Berman. "Design Optimization of Driveshaft and Universal Joint Using Finite Element Technique." In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-66241.
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Finite Element Analysis (FEA) has been performed on variety of a driveshaft and universal joints based on different shaft materials and shaft different operating angles. A driveshaft is particularly useful in applications such as taking of transferring torque from one piece of equipment to the other such as in vehicle of all kinds. A driveshaft transfers torque from the transmission to the rear end differential since these two pieces of equipment cannot be connected directly. The driveshaft has universal joints located on both ends of the shaft to allow for fluctuations in the angle of the transmission and rear differential. The driveshaft alone is composed of two parts, a female and male end, connected by a spline to allow changes in the length during operation. The driveshaft must be able to withstand the constant torque that is being applied throughout operation in order to increase safety for the operator and machine. Having a lower polar moment of inertia allows the driveshaft to turn with a lower torque value compared to a driveshaft with a higher moment of inertia. It is noted that driveshaft can be manufactured into a variety of lengths and diameters depending on the use and equipment it will be supporting. This paper describes a method of finite element implemented on variations of driveshaft and universal joints. Effect of material properties, geometry and operating angle of the driveshaft were considered for this numerical investigation. Five different materials such as structural steel, aluminum alloy, polyethylene, titanium, and carbon fiber with an outer diameter of 1.5 in of the driveshaft was used for this analysis. The effect of both metals and composite materials was observed. Based on the analysis it was found that a 15° operating angle allowed for the longest life cycle of the driveshaft, while the carbon fiber composite presented the highest stress resistance and safety factor, approximately 6 GPa of yield tensile strength and a safety factor of 15. It was also found that titanium had an equivalent safety factor of 15. However, the tensile yield strength of titanium was much lower than that of its composite counterpart. All of the numerical experimentation was done using the Finite Element Analysis software ANSYS. Material properties for all materials were preset in the software except the composite carbon fiber whose properties were easily found from other research papers and experiments. Based on the data collected and the general assumptions that the most effective drive shaft is the one that lasts the longest. It can be concluded that a driveshaft made of carbon fiber operating at an angle of 15° presents the optimum driveshaft design.
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Giebmanns, A., R. Schnell, W. Steinert, A. Hergt, E. Nicke, and C. Werner-Spatz. "Analyzing and Optimizing Geometrically Degraded Transonic Fan Blades by Means of 2D and 3D Simulations and Cascade Measurements." In ASME Turbo Expo 2012: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/gt2012-69064.
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The present study deals with the influence of geometrically degraded transonic engine fan blades on the fan’s aerodynamic behavior. The study is composed of three phases; the first consists of 3D simulations to point out changes in the performance parameters caused by blade degradations. In the second phase, 2D optimizations are carried out to determine the potential of redesigning the blade and in the third phase, measurements on a transonic cascade are used to experimentally verify the numeric results. During engine operation as well as maintenance processes, geometric variations of the fan blades, and especially of the blades’ leading edges, are observed. They mainly originate from the ambient conditions under which the engine is operated. Though the deformations of the blade differ widely, several typical degradation types can be identified. In advance of the study, these degradation types have been systematized and simplified models representing different degrees of degradation have been built. In the first phase, the models are aerodynamically analyzed by means of 3D simulations. A high influence on the performance parameters is found for a fan blade exposed to long-term erosion. The model’s characteristics are a blunt leading edge and a reduced chord length. In contrast, the performance parameters of a model representing a re-contoured blade (reduced chord length but reshaped leading edge) are shown to be similar to those of a new fan blade. This leads to the conclusion that an eroded blade may offer almost the initial performance parameters as long as the leading edge is well reshaped. Since the model of the long-term eroded blade shows great changes in the fan’s performance and the best optimization potential, this has been chosen for the further analysis in the following phases. In the second phase, 2D optimizations are applied to three airfoil sections at different heights of the blade. The parameterization used is limited to a small area of the leading edge; the shape of the rest of the blade is kept constant. The optimizations lead to loss reduction and demonstrate the potential of the optimization process. The third phase is carried out in the Transonic Cascade Wind Tunnel of the Institute of Propulsion Technology in Cologne. As the transonic part of the fan blade is the most sensitive to geometric changes, a transonic airfoil with long-term erosion has been chosen. During the tests, the following measurement techniques are applied: Static pressure probes to determine the Mach number distribution, a 3-hole probe to detect exit angle and loss distribution, Schlieren photographs and PIV-measurements to locate the shock system, the L2F method to measure the cascade inflow angle and to resolve the boundary layer distribution and Liquid crystal measurements to observe transition activities. The full analysis of the measurements with PIV, L2F and Liquid Crystals are still in progress, but the evaluation of the loss polar and the Schlieren photographs show increased losses for the degraded blade and a good match with the numeric results.