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3. Climate and genotype influences on carbon fluxes and partitioning in Eucalyptus plantations

Author

Clayton Alcarde Alvares, Otávio Camargo Campoe, Luiz Fabiano Moraes, James Stahl, Dan Binkley, Rafaela Lorenzato Carneiro, José Luiz Stape, Michael G. Ryan, Gabriela Gonçalves Moreira, Robert M. Hubbard, Universidade Federal de Lavras (UFLA), Universidade Estadual Paulista (Unesp), Forestry Science and Research Institute (IPEF), Northern Arizona University, Colorado State University, Rocky Mountain Research Station, Telêmaco Borba, International Paper, and Suzano

Subjects
0106 biological sciences, Wood production, Range (biology), Clonal plantation, Belowground allocation, Genotypes, chemistry.chemical_element, Primary production, Forestry, Drought tolerant, Zoning, Wood productivity, Management, Monitoring, Policy and Law, Photosynthesis, 010603 evolutionary biology, 01 natural sciences, Eucalyptus, Agronomy, chemistry, Environmental science, Carbon, Silviculture, 010606 plant biology & botany, Nature and Landscape Conservation, Carbon flux
Abstract

Made available in DSpace on 2020-12-12T01:32:48Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-11-01 Clonal plantations of Eucalyptus are among the most productive forests in the world, with intensification of silviculture and genetic breeding doubling the wood mean annual increments over the past four decades. The TECHS Project demonstrated that even with intensive silviculture, wood production varies by more than two-fold across environmental gradients, and growth of highly selected clones differs by more than two-fold within a site. Wood production accounts for less than half of the photosynthesis of a forest, and we tested two hypotheses about the relation between wood production and the entire carbon balance for five genotypes across four of the TECHS sites, varying in temperature and water availability. We hypothesized that the influence of the environment on carbon fluxes and partitioning related to gross primary production would be consistent across genotypes. We also hypothesized that carbon flux and partitioning would be more sensitive to water stress than temperature. Annual average temperatures ranged from 18 to 27 °C, and annual rainfall ranged from about 600 to 1500 mm yr−1. Water stress was further tested by reduction in rainfall within sites using troughs to capture about 30% of incoming rain. The geographic gradient led to a six-fold range in wood net primary production during the two years of measurement (from age 1.5 to 3.5 years, the period of maximum current annual increment). Gross primary production (GPP) differed only by two-fold, highlighting very large differences among sites in partitioning: wood net primary production (NPP) accounted for 44% of GPP on sites with higher GPP, and only 34% of GPP on lower GPP sites. The average differences for wood NPP among clones was also large, with about half of the differences among clones relating to differences in GPP, and half to differences in the partitioning to wood NPP. The clones showed similar partitioning patterns across sites, supporting our first hypothesis. Differences across sites and clones in partitioning of GPP to wood NPP related inversely to belowground allocation. Belowground partitioning of carbon increased with increasing temperature and increasing water stress. Our second hypothesis was rejected, as patterns across sites related somewhat more strongly to temperature than to water stress. Overall, this ecophysiological investigation in the TECHS Project underscored the importance of understanding how carbon budgets differ across sites (even with intensive silviculture), and why clones can largely differ in wood production. Department of Forest Sciences Federal University of Lavras (UFLA) Department of Forest Soils and Environmental Sciences São Paulo State University (UNESP) Forestry Science and Research Institute (IPEF) School of Forestry Northern Arizona University Natural Resource Ecology Laboratory Colorado State University USDA Forest Service Rocky Mountain Research Station Klabin Telêmaco Borba International Paper Suzano Department of Forest Soils and Environmental Sciences São Paulo State University (UNESP)

Published
2020

4. Autonomous hydrogen production for proton exchange membrane fuel cells PEMFC

Author

Manuel Legree, Jean-Louis Bobet, Fabrice Mauvy, F. Bos, Matthieu Faessel, Jocelyn Sabatier, Abdel Salam Awad, Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie Physique des Matériaux (LCPM), Université Libanaise, Laboratoire de l'intégration, du matériau au système (IMS), Université Sciences et Technologies - Bordeaux 1-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS), Université de Bordeaux (UB), and The authors acknowledge the AST society, the Aquitaine SATT, for the funding of the prototype presented in this paper in the form of the HELP maturation project.

Subjects
command law, Materials science, Hydrogen, Magnesium, 020209 energy, Proton exchange membrane fuel cell, chemistry.chemical_element, 02 engineering and technology, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Hydrogen generation, 7. Clean energy, hydrolysis reaction, Hydrolysis, chemistry, Chemical engineering, Transition metal, Yield (chemistry), 0202 electrical engineering, electronic engineering, information engineering, Graphite, Mg-based materials, PEMFC, 0210 nano-technology, green mobility applications, Hydrogen production
Abstract

International audience; This paper focuses on hydrogen production for green mobility applications (other applications are currently under investigation). Firstly, a brief state of the art of hydrogen generation by hydrolysis with magnesium is shown. The hydrolysis performance of Magnesium powder ball–milled along with different additives (graphite and transition metals TM = Ni, Fe, and Al) is taken for comparison. The best performance was observed with Mg–10 wt.% g mixtures (95% of theoretical hydrogen generation yield in about 3 min). An efficient solution to control this hydrolysis reaction is proposed to produce hydrogen on demand and to feed a PEM fuel cell. Tests on a bench fitted with a 100 W Proton Exchange Membrane (PEM) fuel cell have demonstrated the technological potential of this solution for electric assistance applications in the field of light mobility.

Published
2020

5. Cationic Biphotonic Lanthanide Luminescent Bioprobes Based on Functionalized Cross-Bridged Cyclam Macrocycles

Author

Amandine Roux, Damien Curton, Maryline Beyler, Raphaël Tripier, Véronique Patinec, Anh Thy Bui, Sophie Brasselet, Olivier Maury, Jean-Christophe Mulatier, Alexei Grichine, Jonathan Mendy, Chantal Andraud, François Riobé, Alain Duperray, Boris Le Guennic, Yannick Guyot, RENARD, NICOLAS, Chimie, Electrochimie Moléculaires et Chimie Analytique (CEMCA), Université de Brest (UBO)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Brestois Santé Agro Matière (IBSAM), Université de Brest (UBO), Laboratoire de Chimie - UMR5182 (LC), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institute for Advanced Biosciences / Institut pour l'Avancée des Biosciences (Grenoble) (IAB), Centre Hospitalier Universitaire [Grenoble] (CHU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Etablissement français du sang - Auvergne-Rhône-Alpes (EFS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Luminescence (LUMINESCENCE), Institut Lumière Matière [Villeurbanne] (ILM), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), MOSAIC (MOSAIC), Institut FRESNEL (FRESNEL), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), The authors are grateful to the referees for careful reading of the paper and valuable suggestions and comments. The authors also acknowledge support of the Ministère de l'Enseignement Supérieur et de la Recherche, the Centre National de la Recherche Scientifique, the Institut National de la Santé et de la Recherche Médicale and the Agence Nationale de la Recherche (SADAM ANR‐16‐CE07‐0015‐02). M.B. and R.T. thanks the ‘‘Service Commun de RMN’’ of the University of Brest. Confocal and 2P facility of the IAB platform was co‐funded thanks to grants of 'Association pour la Recherche sur le Cancer' (ARC, Villejuif, France), 'Ligue vs Cancer' (LCC Isère/Ardèche) and the CPER program. B.L.G. thanks the French GENCI‐CINES center for high‐performance computing resources., Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), Université de Lyon-Université de Lyon, Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and ANR-16-CE07-0015,SADAM,Diagnostiquer et guérir par des agents azamacrocycliques multimodaux(2016)

Subjects
Lanthanide, Ytterbium, Macrocyclic Compounds, Luminescence, chemistry.chemical_element, 02 engineering and technology, Europium(III), 010402 general chemistry, Photochemistry, 01 natural sciences, Lanthanoid Series Elements, chemistry.chemical_compound, Coordination Complexes, Cations, Cell Line, Tumor, Cyclam, [CHIM] Chemical Sciences, Humans, [CHIM]Chemical Sciences, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Physical and Theoretical Chemistry, Ytterbium(III), Two-photon microscopy, Density Functional Theory, Photons, Aqueous solution, Luminescent Agents, Spectroscopy, Near-Infrared, Molecular Structure, Chemistry, Optical Imaging, Cationic polymerization, Bioprobe, [CHIM.COOR] Chemical Sciences/Coordination chemistry, 021001 nanoscience & nanotechnology, Bioimaging, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, Solvent, 0210 nano-technology, Europium
Abstract

Cationic lanthanide complexes are generally able to spontaneously internalize into living cells. Following our previous works based on diMe-cyclen framework, a second generation of cationic water-soluble lanthanide complexes based on a constrained cross-bridged cyclam macrocycle functionalized with donor-p-conjugated picolinate antennas has been prepared with europium(III) and ytterbium(III). Their spectroscopic properties were thoroughly investigated in various solvents and rationalized with the help of DFT calculations. A significant improvement is observed in the case of the Eu3+ complex, while the Yb3+ analogous conserve an excellent brightness in aqueous solvent. Two-photon (2P) microscopy imaging experiments on living T24 human cancer cells confirmed the spontaneous internalization of the probes and images with good signal-to-noise have been obtained in the classical NIR-to-visible configuration with Eu3+ luminescent bioprobe and in the NIR-to-NIR with the Yb3+ one.

Published
2020

6. Forest production efficiency increases with growth temperature

Author

Alessandro Cescatti, Alessio Collalti, Andreas Ibrom, Giorgio Matteucci, Marcos Fernández-Martínez, Ramdane Alkama, Daniel S. Goll, Julia Pongratz, Philippe Ciais, Anders Stockmarr, Vanessa Haverd, Stephen Sitch, Julia E. M. S. Nabel, Iain Colin Prentice, Pierre Friedlingstein, Almut Arneth, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), FOE-2019 College of Natural Resources, University of California Berkeley, CNR: DTA.AD003.474, We thank R.H. Waring, S. Vicca, M. Campioli, F. Pagani and E. Grieco for early constructive comments and thoughtful suggestions, S. Noce for the map of data points. We thank efforts from all site investigators and their funding agencies. This paper contributes to the AXA Chair Programme in Biosphere and Climate Impacts and the Imperial College initiative Grand Challenges in Ecosystems and the Environment. A.C. and G.M. are partially supported by resources available from the Ministry of University and Research (FOE-2019), under the project 'Climate Change' (CNR DTA.AD003.474), M.F.-M. is a postdoctoral fellow of the Research Foundation—Flanders (FWO), AXA Research Fund, and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)

Subjects
0106 biological sciences, 010504 meteorology & atmospheric sciences, General Physics and Astronomy, adaptation, Atmospheric sciences, 01 natural sciences, Nutrient, Forest production efficiency, ddc:550, SDG 13 - Climate Action, gpp, lcsh:Science, Plant ecology, chemistry.chemical_classification, forest productivity, Carbon dioxide in Earth's atmosphere, Biomass (ecology), Multidisciplinary, Climate-change ecology, Biogeography, [SDE]Environmental Sciences, Engineering sciences. Technology, primary production, biomass production efficienty, Science, carbon use efficiency, chemistry.chemical_element, General Biochemistry, Genetics and Molecular Biology, Article, Latitude, Organic matter, Ecosystem, Precipitation, Biology, 0105 earth and related environmental sciences, Computer. Automation, npp, Primary production, General Chemistry, 15. Life on land, Earth sciences, chemistry, 13. Climate action, Environmental science, lcsh:Q, Forest ecology, Carbon, 010606 plant biology & botany
Abstract

Forest production efficiency (FPE) metric describes how efficiently the assimilated carbon is partitioned into plants organs (biomass production, BP) or—more generally—for the production of organic matter (net primary production, NPP). We present a global analysis of the relationship of FPE to stand-age and climate, based on a large compilation of data on gross primary production and either BP or NPP. FPE is important for both forest production and atmospheric carbon dioxide uptake. We find that FPE increases with absolute latitude, precipitation and (all else equal) with temperature. Earlier findings—FPE declining with age—are also supported by this analysis. However, the temperature effect is opposite to what would be expected based on the short-term physiological response of respiration rates to temperature, implying a top-down regulation of carbon loss, perhaps reflecting the higher carbon costs of nutrient acquisition in colder climates. Current ecosystem models do not reproduce this phenomenon. They consistently predict lower FPE in warmer climates, and are therefore likely to overestimate carbon losses in a warming climate., Many models assume a universal carbon use efficiency across forest biomes, in contrast to assumptions of other process-based models. Here the authors analyse forest production efficiency across a wide range of climates to show a positive relationship with annual temperature and precipitation, indicating that ecosystem models are overestimating forest carbon losses under warming.

Published
2020

7. Differential manganese and iron recycling and transport in continental margin sediments of the Northern Gulf of Mexico

Author

Laurie Bréthous, Bruno Bombled, Jordon S. Beckler, Martial Taillefert, Bruno Lansard, Shannon M. Owings, Anthony D. Boever, Eryn M. Eitel, Edouard Metzger, Benjamin P. Fields, Christophe Rabouille, School of Earth and Atmospheric Sciences [Atlanta], Georgia Institute of Technology [Atlanta], Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Harbor Branch Oceanographic Institute [Fort Pierce], Florida Atlantic University [Boca Raton], Océan et Interfaces (OCEANIS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), National Science Foundation, NSF: OCE-1438648 Office for Science and Technology of the Embassy of France in the United States, OST 2000007281, We would like to thank the captain and crew of the RV Savannah as well as Emily Buckley, Julien Richirt, and Andrew Stancil for help with sample collection and/or analysis. This research was supported by the National Science Foundation ( OCE-1438648 ) to M. Taillefert, EC2CO-DRIL MissRhoDia project to C. Rabouille, National Academies of Science, Engineering, and Medicine Gulf Research Program (Early Career Grant 2000007281 ) to J. Beckler, and the Chateaubriand Fellowship of the Office for Science & Technology of the Embassy of France in the United States awarded to S. Owings. Finally, we thank the editor and two anonymous reviewers for their insightful comments and suggestions which helped improve this paper significantly., Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)

Subjects
0106 biological sciences, Anaerobic respiration, 010504 meteorology & atmospheric sciences, Nepheloid layer, chemistry.chemical_element, Diagenetic processes, Manganese, Oceanography, 01 natural sciences, River-dominated margins, Continental slope sediments, Continental margin, Manganese and iron cycling, River mouth, Environmental Chemistry, Mississippi delta, Reduction, 0105 earth and related environmental sciences, Water Science and Technology, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, geography, geography.geographical_feature_category, Continental shelf, 010604 marine biology & hydrobiology, Sediment, General Chemistry, Sedimentation, Sulfate, Northern Gulf of Mexico, chemistry, 13. Climate action, Environmental chemistry, Environmental science
Abstract

International audience; Pore water and solid phase geochemical profiles of sediment cores collected along two transects on the western and eastern sides of the Mississippi River mouth in the northern Gulf of Mexico were incorporated into a reactive transport model to determine the role of manganese and iron in the remineralization of carbon. Reactive transport model calculations indicate that sedimentation rates control the intensity of anaerobic carbon remineralization and select for the dominant anaerobic carbon remineralization pathways. Although sulfate reduction dominates the shelf station (65 m water depth), denitrification and microbial manganese reduction appear equally significant anaerobic respiration processes along the continental slope the closest to the Mississippi River, whereas microbial iron reduction does not represent an important process in these sediments. These findings suggest that the differential kinetics of manganese and iron redox transformations influence carbon remineralization processes on the continental slope. The fast kinetics of Fe2+ oxidation near the sediment-water interface and high sedimentation rates maintain Fe under the form of Fe(III) oxides and thermodynamically prevent sulfate reduction from dominating carbon remineralization processes on the slope, whereas the much slower Mn2+ oxygenation kinetics allows diffusion of Mn2+ across the sediment-water interface of the shelf station closest to the river mouth. Exposure to oxygenated bottom waters and entrainment within mobile muds typical of deltaic sediments during high riverine discharge likely promote the formation and downslope transport of Mn(III/IV) oxides within the nepheloid layer. This phenomenon appears to form a manganese ‘conveyor belt’ that selectively enriches Mn(III/IV) oxides relative to Fe(III) oxides in the deep sediment. In contrast, the intensity of anaerobic carbon remineralization processes along the eastern continental slope the farthest from the Mississippi River plume is much lower due to the low organic and lithogenic inputs, and denitrification dominates anaerobic respiration. Overall, these findings suggest that manganese cycling and its role in carbon remineralization processes in continental slope sediments exposed to large riverine inputs may be more important than previously considered.

Published
2021

8. Influence of the electrografting method on the performances of a flow electrochemical sensor using modified electrodes for trace analysis of copper (II)

Author

Cecilia Cristea, Robert Săndulescu, Cristelle Mériadec, Florence Geneste, Ionel Fizesan, Bogdan Feier, Soraya Ababou Girard, Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Cluj-Napoca, facultatea, Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), This paper was published under the frame of European Social Found, Human Resources Development Operational Programme 2007–2013, Project No. POSDRU/159/1.5/S/136893. The authors are also thankful for the financial support to 'Iuliu Hatieganu' University of Medicine and Pharmacy of Cluj-Napoca, for the research Grant 1491/8/28.01.2014 and for their help to Ioana Băjan, Ana Gui and Ioana Ionel, students of 'Iuliu Hatieganu' University of Medicine and Pharmacy, Faculty of Pharmacy., Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Copper detection, [CHIM.ORGA]Chemical Sciences/Organic chemistry, General Chemical Engineering, Electrografting, Inorganic chemistry, Open circuit preconcentration, chemistry.chemical_element, Electrochemistry, Copper, Analytical Chemistry, Electrochemical gas sensor, chemistry.chemical_compound, chemistry, Electrode, Cyclam, Graphite, Cyclic voltammetry, Voltammetry, Sensor
Abstract

The performances of carboxylate- and cyclam-modified graphite felt electrodes prepared by different electrografting methods for trace analysis of copper (II) were compared to determine the influence of the immobilization process of the linkers on the sensor properties. The derivatization performed by cathodic reduction of diazonium salts and by anodic oxidation of amines in organic and aqueous media was first evaluated by cyclic voltammetry and X-ray photoelectron spectroscopy analyses, showing a higher surface coverage for the reduction process. Cyclam was subsequently attached on the COOH-modified graphite felts by a coupling reaction. The modified electrodes were then employed in a flow analytical system for trace analysis of copper (II) ions. The influence of the surface coverage and the nature of the linker on the electrochemical signal obtained by linear sweep stripping voltammetry analysis after a preconcentration step performed at open circuit was highlighted. The selectivity estimated in the presence of lead used as a common ion interferent was higher when a selective receptor was used and depends on the nature of the linker.

Published
2015