Journal articles: 'Synthèse graphique'

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Hufty, André. "Situations synoptiques et analyse multivariée des temps à Québec." Cahiers de géographie du Québec 20, no. 49 (April 12, 2005): 69–92. http://dx.doi.org/10.7202/021310ar.

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Les situations synoptiques et les gradients de température dans les basses couches de l'atmosphère ont été étudiés pendant une année à Québec, et les conditions du temps qui en dépendent ont été soumises à une analyse multivariée. Cette dernière montre que les éléments journaliers du temps se regroupent sous deux composantes principales: le rayonnement solaire absorbé au sol et le « potentiel hydrique », une fonction directe de l'humidité absolue et inverse du déficit de saturation. Les relations entre les situations synoptiques et les deux composantes principales qui résument les conditions du temps sont présentées sous forme graphique et dans un tableau de probabilité, qui permettent de faire la synthèse entre les deux types de classements des temps journaliers.

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Khalloufi-Mouha, Faten. "Utilisation du modèle de classe inversée pour l’introduction des Séries de Fourier en première année universitaire." ITM Web of Conferences 39 (2021): 01011. http://dx.doi.org/10.1051/itmconf/20213901011.

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Dans ce papier, nous décrivons la mise en place d’une expérience de classe inversée pour l’introduction de la notion de série de Fourier à des étudiants de première année universitaire en sciences de l’informatique de la faculté des sciences de Bizerte en Tunisie. Dans l’objectif d’explorer l’impact de ce dispositif pédagogique sur l’apprentissage des mathématiques et en se plaçant dans le cadre de la théorie commognitive, nous avons cherché à étudier l’appropriation par les étudiants, des routines identifiées dans les capsules vidéos qui introduisent le contenu mathématique visé. Sur le plan pédagogique, les premiers résultats font apparaitre une hétérogénéité importante chez les étudiants qui a amené l’enseignante que nous sommes à mettre en place une méthode hybride qui consiste à introduire une séance de synthèse qui a suivi la visualisation des capsules vidéos. Sur le plan didactique, nous avons étudié l’individualisation par les étudiants des trois types de routines associées aux séries de Fourier: les routines de traitement graphique, les routines de traitement calculatoire et les routines de justification et de preuve.

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Yagouti, A., I. Abi-Zeid, T. B. M. J. Ouarda, and B. Bobée. "Revue de processus ponctuels et synthèse de tests statistiques pour le choix d'un type de processus." Revue des sciences de l'eau 14, no. 3 (April 12, 2005): 323–61. http://dx.doi.org/10.7202/705423ar.

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Nous nous intéressons dans ce travail de recherche à la modélisation d'une série d'événements par la théorie des processus ponctuels temporels. Un processus ponctuel est défini comme étant un processus stochastique pour lequel chaque réalisation constitue une collection de points. Un grand nombre d'ouvrages traitent particulièrement de ces processus, cependant, il existe dans la littérature peu de travaux qui se préoccupent de l'analyse de séries d'événements. On identifie deux catégories de séries d'événements : une série d'un seul type d'événements et une série de plusieurs types d'événements. L'objectif de ce travail est de mettre en évidence les différents tests statistiques appliqués aux séries d'un seul ou de plusieurs types d'événements et de proposer une classification de ces tests. Nous présentons d'abord une revue de littérature des processus ponctuels temporels, accompagnée d'une classification de ces modèles. Par la suite, nous identifions les tests statistiques de séries d'un seul type d'événements et nous examinons leur applicabilité pour une série de deux ou de plusieurs types d'événements. Les tests statistiques identifiés sont répartis en quatre classes : analyse graphique, tests appliqués au processus de Poisson homogène et non homogène, tests appliqués au processus de renouvellement homogène et les tests de discrimination entre deux processus ponctuels. Ce travail est réalisé avec l'idée d'une application ultérieure dans le cadre de l'analyse du risque. Les résultats de cette recherche ont montré qu'il n'existe dans la littérature que des tests d'une série d'un seul type d'événements et ils sont, généralement, valables pour les processus ponctuels suivants : Poisson homogène et renouvellement homogène. L'application de ces tests aux séries de deux ou de plusieurs types d'événements est possible dans le cas où les événements sont définis par leurs nombres et leurs temps d'occurrence seulement, i.e. la durée de chaque événement n'est pas prise en considération.

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Patin, Nicolas, Eric Monmasson, Jean-Paul Louis, and Lionel Vido. "Schémas dynamiques phasoriels, un formalisme graphique pour la synthèse de commandes de générateurs électriques. Application à la machine asynchrone à double alimentation." Revue internationale de génie électrique 10, no. 1-2 (May 9, 2007): 27–53. http://dx.doi.org/10.3166/rige.10.27-53.

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Matalliotaki, Eirini, and Jean-Marie Boilevin. "Sous quelles conditions les représentations graphiques externes peuvent-elles favoriser l’apprentissage des enfants d’âge préscolaire ?" Revue des sciences de l’éducation 41, no. 2 (November 17, 2015): 219–49. http://dx.doi.org/10.7202/1034034ar.

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Cet article théorique vise à déterminer à quelles conditions l’utilisation des représentations graphiques externes facilite l’apprentissage chez les jeunes enfants, afin de proposer un modèle théorique de conception de tâches cognitivement efficaces pour l’apprentissage. Nous avons repéré trois notions que nous considérons comme essentielles dans le processus d’apprentissage de et à travers la fonction symbolique des représentations graphiques : la décontextualisation, la métacognition et le statut de représentation des représentations graphiques. La synthèse théorique de ces notions, illustrée par des exemples empiriques sur des tâches en mathématiques avec des dessins, conduit à la conception d’un modèle théorique de préparation de tâches qui devrait faciliter l’apprentissage à travers les représentations symboliques. Ce modèle pourrait être applicable dans le domaine des sciences ou sur des données textuelles pour produire des inférences. L’objectif à long terme est de faciliter l’accès des enfants à la conception et à la compréhension des représentations symboliques plus tard dans leur scolarité.

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Kaiser, P., A. Messaoudi, D. Bonnin, R. Erre, and F. Béguin. "Synthèse et caractérisation de métaux finement divisés supportés sur graphite." Journal de Chimie Physique 86 (1989): 1787–92. http://dx.doi.org/10.1051/jcp/1989861787.

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7

Montigaud, Hervé, Bernard Tanguy, Gérard Demazeau, Sébastien Courjault, Marc Birot, and Jacques Dunogues. "Sur la synthèse de C3N4 de structure graphitique par voie solvothermale." Comptes Rendus de l'Académie des Sciences - Series IIB - Mechanics-Physics-Chemistry-Astronomy 325, no. 4 (August 1997): 229–34. http://dx.doi.org/10.1016/s1251-8069(97)88282-6.

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8

Wang, Bingzhe, Verena Engelhardt, Alexandra Roth, Rüdiger Faust, and Dirk M. Guldi. "n- versus p-doping of graphite: what drives its wet-chemical exfoliation?" Nanoscale 9, no. 32 (2017): 11632–39. http://dx.doi.org/10.1039/c7nr03379f.

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We have performed the syntheses of a novel pyrene-porphyrazine conjugate (ZnPzPy) and a reference porphyrazine (ZnPz) to promote the wet-chemical exfoliation of graphite based on the synergetic use of ultrasonication, centrifugation, and doping.

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Claval, Paul. "La logique de l’enseignement de la géographie dans les universités." Cahiers de géographie du Québec 14, no. 31 (April 12, 2005): 49–62. http://dx.doi.org/10.7202/020899ar.

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L'auteur présente les grandes lignes d'un programme d'enseignement supérieur de la géographie, adapté aux tendances modernes de cette discipline. L'initiation à la géographie est abordée par l'étude des mécanismes écologiques. On passe ensuite à l'examen des principes et des lois générales. Un panorama de la géographie naturelle s'impose : la zonalité et ses conséquences écologiques, le rôle des forces internes, la géographie physique générale, les synthèses évolutives et régionales. La géographie humaine doit elle aussi s'appuyer sur les liaisons écologiques. Les forces sociales seront envisagées en rapport avec l'espace, et l'étudiant aura intérêt à s'initier aux branches voisines des sciences humaines : sociologie, sciences économiques, anthropologie. L'enseignement de la géographie humaine générale ne saurait être complet sans l'étude des grandes synthèses historiques et régionales. Il est important de ne pas négliger les méthodes de travail nécessaires à la recherche : l'expression graphique et statistique sont les deux principales, mais il ne faut pas oublier non plus les techniques de documentation et de critique des textes. En terminant, l'auteur conclut que l'enseignement supérieur de la géographie doit réaliser un équilibre judicieux entre l'enseignement de type encyclopédique, qu'il appelle enseignement de contenu, et l'enseignement méthodologique qui nécessite plus d'effort individuel. Il s'agit, en un mot, d'adapter les méthodes d'enseignement de la géographie aux exigences du monde moderne.

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Trusova, Elena A., Klara V. Kotsareva, Alexey N. Kirichenko, Sergey S. Abramchuk, and Igor A. Perezhogin. "Sonochemical Preparation and Subsequent Fixation of Oxygen-Free Graphene Sheets at N,N-Dimethyloctylamine-Aqua Boundary." Advances in Materials Science and Engineering 2018 (2018): 1–11. http://dx.doi.org/10.1155/2018/6026437.

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In this study, the syntheses of oxygen-free graphene sheets and the method of its fixation at an oil-aqua interface were presented. The graphene sheets were prepared by exfoliation of synthetic graphite powder in an aqua-organic medium under ultrasound irradiation. N,N-Dimethyloctylamine- (DMOA-) aqua emulsion was used as the liquid medium, and pH was equal to 3. The obtained graphene nanosuspension was fractionated by sedimentation and decanted according to the weight. The graphene nanoparticle fractions, differing in configuration and number of layers, have been characterized using transmission electron microscopy (TEM), electron diffraction, HRTEM, Raman spectroscopy, and electron energy loss spectroscopy (EELS). It was found that using a DMOA-aqua mixture as the liquid medium in ultrasonic treatment of synthetic graphite leads to the formation of oxygen-free 1-2-layer graphene sheets attached to the DMOA-aqua interface. The proposed method differs from known ones by using a small amount of more environmentally friendly organic substances. It allows to obtain large quantities of oxygen-free graphene, and finally unconverted graphite can be directed for reuse. The proposed method allows to obtain both 2D graphene sheets with micron linear dimensions and 3D packages with a high content of defects. Both these species are in demand in areas related to the development of new materials with unique electrophysical properties.

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Lukowiak, Anna, Yuriy Gerasymchuk, Anna Wedzynska, Leili Tahershamsi, Robert Tomala, Wieslaw Strek, Dominika Piatek, et al. "Light-Activated Zirconium(IV) Phthalocyanine Derivatives Linked to Graphite Oxide Flakes and Discussion on Their Antibacterial Activity." Applied Sciences 9, no. 20 (October 20, 2019): 4447. http://dx.doi.org/10.3390/app9204447.

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In search of an effective antibacterial agent that is useful in photodynamic therapy, new derivatives of zirconium(IV) phthalocyanine (ZrPc) complexes were obtained and linked to graphite oxide flakes. In the syntheses of ZrPc derivatives, two bis-axially substituted ligands with terminal amino group and different lengths of linear carbon chain (C4 in 4-aminobutyric acid or C11 in 11-aminoundecanoic acid) were used. The optical properties (absorption and photoluminescence spectra) of ZrPcs and the composites were examined. Broadband red–near-infrared lamp was tested as an external stimulus to activate ZrPcs and the composites. Optical techniques were used to show generation of singlet oxygen during irradiation. Considering the application of graphite oxide-based materials as bacteriostatic photosensitive additives for endodontic treatment of periapical tissue inflammation, the antibacterial activity was determined on one Escherichia coli strain isolated directly from an infected root canal of a human tooth and one strain with silver and antibiotic resistance. Looking at the obtained results, modified levels of activity toward different bacterial strains are discussed.

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12

Ambroise, B. "Génèse des débits dans les petits bassins versants ruraux en milieu tempéré: 1 - Processus et facteurs." Revue des sciences de l'eau 11, no. 4 (April 12, 2005): 471–96. http://dx.doi.org/10.7202/705317ar.

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La première des deux parties de cette synthèse bibliographique sur la genèse des débits montre que la complexité et la diversité des organisations et fonctionnements hydrologiques constatées dans les petits bassins versants ruraux peuvent s'analyser et s'interpréter à l'aide de "clés de lecture" simples, issues d'une approche systémique et dynamique, et utiles aussi pour les modéliser (cf. Partie 2). Elle présente les différents processus tant superficiels que souterrains pouvant contribuer à cette genèse, ainsi que les facteurs du milieu qui les contrôlent: forçages atmosphériques aux limites, conditions hydriques et hydrologiques initiales, propriétés hydrodynamiques des milieux et interfaces traversés, topographie et morphométrie en 3-D du bassin. Elle rappelle ou introduit plusieurs concepts utiles pour caractériser dans chaque cas les combinaisons de processus et facteurs en jeu et leurs effets hydrologiques: seuils fonctionnels et grandeurs caractéristiques contrôlant la forme et la non-linéarité de la réponse du bassin, concepts de "zone ou période active variable" pour un processus donné et de "zone ou période contributive variable" pour un flux aux limites donné décrivant son organisation interne. Elle discute les avantages et limites des différentes méthodes (graphiques, isotopiques, géochimiques) de décomposition des hydrogrammes de crue ainsi que leur complémentarité dans l'étude du système bassin versant.

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Elizarraras Peñaloza, Alejandro, Miriam Estrada Flores, Carmen Magdalena Reza San Germán, Lucía Graciela Díaz Barriga Arceo, Patricia Santiago Jacinto, and María Elena Manríquez Ramírez. "Change of phase from ?-Bi2O3 to ?-Bi2O3 using the ceramic microwave-assisted approach and its increase of capacitance." Superficies y Vacío 32 (December 15, 2019): 14–21. http://dx.doi.org/10.47566/2019_syv32_1-010014.

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The use of microwaves for the synthesis of materials is very important due to its versatility, it is an economical option, friendly with the environment, generates a low energy demand and the syntheses are carried out in very short times. There are many methods that use microwaves to obtain materials, however, the simplest one is the ceramic method, which consists in blending by grinding the reagents or precursors, which are placed in a quartz cell and finally carried to the microwave oven for synthesis. The reagents used to carry out this research are ?-Bi2O3 and graphite. The phase change in the ?-Bi2O3 was obtained despite the differences in weight composition and the variation of power level and irradiation time inside the microwave oven. X-ray diffraction and scanning electron microscopy were used to verify the phase and morphology of the samples before and after irradiation. The last step of this work was the capacitance measurement of the composites made of 0.39 g of alumina and 0.01 g of the product of graphite and bismuth oxide after irradiation at different conditions. The results demonstrated an increasing of capacitance in all the samples conformed by ?-Bi2O3/C/Al2O3.

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El Gadi, M., C. Herold, and P. Lagrange. "Des doubles couches de potasium insérées dans le graphite: synthèse de composés de stades 1, 2, 3 et 4." Carbon 32, no. 4 (1994): 749–52. http://dx.doi.org/10.1016/0008-6223(94)90099-x.

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15

Behrens, Peter, Mehdi Alidoosti, Frank Schulz, and Wolfgang Metz. "Synthese und Struktur von Graphit-Einlagerungsverbindungen des Quecksilber(II)-chlorids / Synthesis and Structure of the Graphite Intercalation Compounds of Mercuric Chloride." Zeitschrift für Naturforschung B 44, no. 7 (July 1, 1989): 721–28. http://dx.doi.org/10.1515/znb-1989-0702.

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Graphite intercalation compounds (GICs) of mercuric chloride have been synthesized by four different methods: via the vapour phase, from melts of pure HgCl2, from melts of HgCl2, and alkali metal chlorides, and from solutions in concentrated aqueous HCl. Compounds of stages 4, 3 and 2 were obtained, respectively. GICs prepared from solution always show staging disorder. Pure stage compounds of stage three and four exhibit the following repeat distances along the c⃗ axis: c(3) = 1632 pm; c(4) = 1968 pm. Further structural analysis is hindered by the disorder phenomena common to GICs. Rather surprisingly, monochromatic Laue photographs probing the in-plane order of the intercalate reveal that - regardless of the preparation method - the diffraction patterns of all compounds are identical. The main phase possesses a monoclinic in-plane lattice with cell dimensions: a = 390(4) pm, b = 412(4) pm, γ = 108.6(3)°. A structure which resembles certain features of the structure of pristine HgCl2 is proposed for this phase. Another unidentified phase seems to stabilize this structure in spite of different amounts of chlorine excess probably occurring in compounds prepared in different ways.

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Li, Z. G., L. Liang, P. J. Fagan, and M. van Kavelaar. "The Three-Dimensional shape of carbon nanotubes by High Resolution Electron Microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 51 (August 1, 1993): 754–55. http://dx.doi.org/10.1017/s042482010014960x.

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Following the discovery of a large scale synthesis of fullerenes, the existence of the related carbon nanotubes was suggested by high resolution electron microscopy (HREM). Larger scale syntheses of these nanotube-rich materials has now been reported and has sparked interest worldwide. Because the HREM technique essentially observes the projection of a three dimensional object onto a two-dimensional plane, the three dimensional shape of the object is usually not apparent in typical HREM images. However, as we report here, by rotating along the axis of single carbon nanotube, and recording the images in succession by HREM, the non-cylindrical nature of these tubes is revealed, especially near the sealed ends of the nanotubes. In addition, from electon diffraction and X-ray diffraction, we find the spacing between the planes to be 3.398(8) Å on average. This is in contrast to earlier reports which suggested an interlayer distance of 3.35 Å, similar to the graphite interplanar spacing.

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17

Blagoveshchenskiy, Yu V., N. V. Isaeva, E. A. Lantsev, M. S. Boldin, V. N. Chuvil’deev, A. V. Nokhrin, A. A. Murashov, et al. "Spark plasma sintering of WC – 10 Co nanopowders with various carbon content obtained by plasma-chemical method." Perspektivnye Materialy, no. 8 (2020): 73–86. http://dx.doi.org/10.30791/1028-978x-2020-8-73-86.

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The features of high-speed sintering of WC – Co nanopowders with various contents of excess carbon (colloidal graphite) were studied. To obtain powders, a process was used that included plasma-chemical and low-temperature syntheses and a chemical-metallurgical method of applying ultrathin cobalt layers by precipitation from a solution of salts. The consolidation of powder materials was carried out by the method of high-speed Spark Plasma Sintering. It was found that an increase in the concentration of free carbon (colloidal graphite) has the greatest effect on the shrinkage and sintering rate at the stage of intense shrinkage of WC-Co nanopowders. It is shown that an increase in the carbon content in the composition of nanopowders leads to a decrease in the value of sintering activation energy at the stage of intense shrinkage.It has been established that the process of nanopowder compaction at the intense shrinkage stage is determined by the intensity of the plastic flow and the grain boundary diffusion of cobalt. It is shown that the mechanism of plastic deformation of the γ-phase based on cobalt corresponds to the Coble diffusion creep. It was found that an increase in carbon content leads to decreased in activation energy at the intense shrinkage and does not significantly affect at stage III of sintering where decrease in the shrinkage intensity is observed. It was shown that a decrease in the sintering activation energy is due to a decrease in the tungsten concentration in the γ-phase.

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Sopicka-Lizer, Malgorzata, Tomasz Pawlik, Daniel Michalik, and Radosław Lisiecki. "Engineering of Synthesis of Eu,Ca-α-Sialon Phosphor via the Solid-Liquid Synthesis." Materials Science Forum 904 (August 2017): 125–29. http://dx.doi.org/10.4028/www.scientific.net/msf.904.125.

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The aim of this research was to find out the way of the synthesis temperature reduction without deterioration of the phosphors optical properties. Since crystallization of Eu,Ca-α-sialon occurs by means of sialon crystallization from the oversaturated oxynitride liquid, thus a rise of the liquid phase amount could be performed not only via an increase of temperature but also through the application of the low eutectic additives. Al2O3 and AlF3 additives have been chosen as the sources of liquid at the reaction temperature. The syntheses were carried out in a graphite furnace at 1650°C and the powders were characterized for their phase composition, particles morphology, excitation and emission properties and their quantum yield of luminescence was compared. It has been found that alumina addition to the initial mixture of nitrides was the most effective in formation of sialon solid solution with a minor contamination with AlN. Emission intensity of sialon phosphor was doubled if they were synthesized with each of additives. Quantum yield of tested phosphors was over 0.85 if excited at 380 nm for alumina and similar for AlF3 modified composition. A significant particles refinement was observed if AlF3 was applied.

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Dan, Monica, Adriana Vulcu, Sebastian A. Porav, Cristian Leostean, Gheorghe Borodi, Oana Cadar, and Camelia Berghian-Grosan. "Eco-Friendly Nitrogen-Doped Graphene Preparation and Design for the Oxygen Reduction Reaction." Molecules 26, no. 13 (June 24, 2021): 3858. http://dx.doi.org/10.3390/molecules26133858.

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Four N-doped graphene materials with a nitrogen content ranging from 8.34 to 13.1 wt.% are prepared by the ball milling method. This method represents an eco-friendly mechanochemical process that can be easily adapted for industrial-scale productivity and allows both the exfoliation of graphite and the synthesis of large quantities of functionalized graphene. These materials are characterized by transmission and scanning electron microscopy, thermogravimetry measurements, X-ray powder diffraction, X-ray photoelectron and Raman spectroscopy, and then, are tested towards the oxygen reduction reaction by cyclic voltammetry and rotating disk electrode methods. Their responses towards ORR are analysed in correlation with their properties and use for the best ORR catalyst identification. However, even though the mechanochemical procedure and the characterization techniques are clean and green methods (i.e., water is the only solvent used for these syntheses and investigations), they are time consuming and, generally, a low number of materials can be prepared, characterized and tested. In order to eliminate some of these limitations, the use of regression learner and reverse engineering methods are proposed for facilitating the optimization of the synthesis conditions and the materials’ design. Thus, the machine learning algorithms are applied to data containing the synthesis parameters, the results obtained from different characterization techniques and the materials response towards ORR to quickly provide predictions that allow the best synthesis conditions or the best electrocatalysts’ identification.

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Setyowati, Vuri Ayu, Diah Susanti, Lukman Noerochim, Eriek Wahyu Restu Widodo, and Mohammad Yusuf Sulaiman. "Investigation of Carbon Composition for Electrochemical Properties as PEMFC Cathode Catalyst." Materials Science Forum 964 (July 2019): 13–18. http://dx.doi.org/10.4028/www.scientific.net/msf.964.13.

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Nitrogen –doped carbon material using non-precious metal was developed as catalyst fuel cell (PEMFC). In the PEMFC, the cathode reaction occurs three times slower than anode reaction. Oxygen reduction reaction (ORR) in the cathode has major limit performance. Pt/C was used as high-cost catalyst materials but many researchers concerned to improve cathode catalyst performance using high-performance and low-cost materials. Nitrogen based active sites on carbon has important role for oxygen reduction reactions process. In this study, compositions of carbon for Fe-N-C were investigated to understand the electrochemical properties and morphological analysis. Urea and PVP as nitrogen (N) source was mixed with graphite (Gt). The ratio of Gt and N were 1:1, 3:1, and 1:3. The mixture was added to FeCl3.6H2O dissolved in ethanol to produce Fe-N/C catalyst. Subsequently powder was introduced to the furnace for the pyrolysis. The catalyst products were analyzed using Potentiostat to show the electrochemical properties of catalyst, X-Ray Diffractometer (XRD) was used to know the compound or phases after catalyst syntheses, Scanning Electron Microscope – Energy Dispersive X-Ray (SEM-EDX) was used to identify the morphology and the chemical compositions of catalyst. As a result, Fe – Gt : N = 1:3 catalyst had the greatest electrochemical properties which is identified by large area of CV curve. This catalyst also had the highest current density for reduction reaction. The presence of Fe2O3 and FeS caused the degreasing of catalytic activity. As conclusions of this research, carbon composition had the important rule to improve the ORR activity.

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Gayda, Galina Z., Olha M. Demkiv, Yanna Gurianov, Roman Ya Serkiz, Mykhailo V. Gonchar, and Marina Nisnevitch. "“Green” Nanozymes: Synthesis, Characterization, and Application in Amperometric (Bio)sensors." Proceedings 60, no. 1 (November 2, 2020): 58. http://dx.doi.org/10.3390/iecb2020-07072.

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Nanozymes (NZs) are catalytically active nanomaterials that have enzyme-like activity but possess increased stability and greater availability due to the fact of their simpler preparation technologies. Nanozymes as nanoscale artificial enzymes demonstrate various catalytic specificities as oxidoreductases, such as peroxidase, catalase, laccase, and others as well as hydrolases, proteases, endonucleases, DNA-ases, NO synthases, etc. A broad variety of NZs exhibits dual- or multienzyme mimetic activity. Nanozymes as stable, low-cost mimetics of natural enzymes have a high potential for application in different branches of biotechnology including scientific investigations, industry, and ecology. Nanozymes can be applied in medicine as diagnostic tools and components of therapeutic drugs. Since NZs have high catalytic activity and chemical and biological stability, they are very promising in the construction of biosensors and biofuel cells. For these reasons, the search for simple methods of synthesis and characterization of different NZs is a very important and real problem. The “green” synthesis of Prussian blue analogous as peroxidase-like NZs using oxido-reductases is described in this study. The obtained green-synthesized hexacyanoferrates (gHCFs) of transition metals were characterized by structure, size, composition, catalytic properties, electro-mediator activities, and substrate specificity. Copper hexacyanoferrate (gCuHCF) was studied in more detail. When immobilized on a graphite electrode (GE), gCuHCF under special conditions of pH and tension gave amperometric signals on hydrogen peroxide and can be used as a peroxidase mimetic in oxidase-based biosensors. Under other conditions, gCuHCF/GE reacts to other analytes. We propose that gHCFs of transition metals synthesized via enzymes may become prospect platforms for the construction of multi-functional amperometric (bio)sensors.

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Gros, Pierre. "Une nouvelle synthèse sur l'architecture religieuse de l'Afrique romaine - JOHANNES EINGARTNER, TEMPLA CUM PORTICIBUS. AUSSTATTUNG UND FUNKTION ITALISCHER TEMPELBEZIRKE IN NORDAFRIKA UND IHRE BEDEUTUNG FÜR DIE RÖMISCHE STADT DER KAISERZEIT (Internationale Archäologie Bd. 92; Marie Leidorf, Rahden2005). Pp. xiii + 243, 63 fig. dans le texte, 41 pl. hors-texte, 22 annexes graphiques (Beilagen). ISBN 3-89646-364-0. EUR. 71.50." Journal of Roman Archaeology 20 (2007): 525–31. http://dx.doi.org/10.1017/s1047759400005821.

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23

GuÉrard, Daniel, and Vera A. Nalimova. "Synthesis of Graphite Intercalation Compounds with Donor Species." MRS Proceedings 369 (1994). http://dx.doi.org/10.1557/proc-369-155.

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AbstractFor 15 years, the chemistry of the intercalation of donors species into graphite has beenlargely developed and a great number of new phases were discovered : over 100 if one takes into account the various stages and stacking, which involves different properties of the compounds for a given intercalate. Four new systems and synthesis methods were developed : intercalation of metallic alloys containing an alkali metal, ionic species (alkali metal hydrides, hydroxides and, even chlorides), alkali metals with oxygen (by addition to the metal of a small quantity of its peroxide M2O2), intercalation under high pressure of the alkali metal. Those new syntheses, still in progress, lead to compounds in which the first stages exhibit a fairly high intercalate/carbon ratio : from LiC2 to MC4 (M = Na, K, Rb or Cs) instead of LiC6 or MC8 obtained by classical methods.The increase of this ratio confers them interesting properties and possibilities of application, especially in the field of new materials for primary or secondary batteries.

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Wang, Xinpeng, Xiaoliang Tang, and Peter Xianping Feng. "Dielectric-barrier discharge plasma source and its application to synthesis of diamond like carbon films." MRS Proceedings 1083 (2008). http://dx.doi.org/10.1557/proc-1083-r03-04.

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ABSTRACTDielectric barrier discharge plasma sources have been studied and used for syntheses of diamond like carbon thin films. The plasma electrical properties under different gases concentrations and pressures were diagnosed. Based on the results of characterizations, dielectric barrier discharge plasma at different methane-hydrogen-argon gas ratios was used to synthesize large area of diamond like carbon films. Experimental data indicate that only at argon concentration equal to or less than 75% diamond like carbon film fabrication could be accomplished, which has been confirmed based on the Raman spectra and their hardness measurements, whereas high argon content during deposition would result in graphite type of thin films.

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Journal articles on the topic 'Synthèse graphique'

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