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Anesthesia, intravenous --- Flumazenil --- Midazolam --- Narcotics --- Nitrogen oxide (n2o) --- Thiopental --- Anesthesia, intravenous --- Flumazenil --- Midazolam --- Narcotics --- Nitrogen oxide (n2o) --- Thiopental
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Ce mémoire a pour objectif d’étudier les variations de concentrations de méthane (CH4) et d’oxyde nitreux (N2O) dans la glace de mer en Arctique central. L’oxyde nitreux et le méthane sont deux des principaux gaz à effet de serre et l’oxyde nitreux est le principal destructeur d’ozone stratosphérique. Malgré tout, la dynamique de ces gaz dans la glace de mer est peu étudiée à ce jour. Ce mémoire s’inscrit dans le cadre de la campagne MOSAiC qui s’est déroulée entre septembre 2019 et octobre 2020, où le R.V . Polarstern a dérivé avec la glace en Arctique central durant un an. Au cours de cette campagne, deux types de glaces ont été échantillonnées, la glace de première année (FYI) et la glace pluri-annuelle (MYI). Les échantillons de glace fondue ont été analysés par chromatographie gazeuse pour la mesure de la concentration en CH4 et N2O. Les gaz se trouvent majoritairement sous forme de bulles au sein de la glace, avec une portion plus faible dissoute dans les saumures. La présence de ces bulles est principalement attribuée à un phénomène physique, le « bubble-driven enrichment ». Le rôle de la glace de mer comme une source ou un puits pour l’atmosphère est discuté, la glace FYI pourrait ainsi agir comme une source de CH4 et de N2O pour l’atmosphère de l’hiver au printemps, le rôle de la glace en été semble moins évident. La formation de « melt ponds » semble fortement impacter les flux de gaz air-glace, notamment pour la MYI. Cette dernière comportait à sa surface des « refrozen melt ponds » qui limitent vraisemblablement le transfert des gaz vers l’atmosphère, aussi les flux vers l’atmosphère de l’hiver au printemps depuis la MYI sont considérés comme très faibles. Notre travail semble montrer la prépondérance des processus physique dans la dynamique du CH4 et N2O durant la campagne MOSAiC, et souligne le peu de compréhension de la perméabilité des gaz dans la glace de mer.
Sea ice --- Methane --- Oxide nitreux --- CH4 --- N2O --- MOSAIC --- Arctic --- glace --- Sciences du vivant > Sciences aquatiques & océanologie
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Report --- TRACE ELEMENTS --- FLUE GASES --- FURNACE FIRING --- SAMPLING --- NITROGEN OXIDE (N2O) --- HALIDES --- ORGANIC COMPOUNDS --- QUALITY CONTROL --- STANDARDS --- ANALYSIS
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Methane. --- Methane --- Nitrates --- Nitrates --- agriculture. --- agriculture --- Gases --- Gases --- Measurement --- Measurement --- Sampling --- Sampling --- Measuring instruments --- Measuring instruments --- methodology --- methodology --- air pollution --- air pollution --- Nonpoint pollution --- Nonpoint pollution --- Nitrogen oxides --- Nitrogen oxides --- Nitrous oxide --- Nitrous oxide --- Manuel --- N2o --- Nox --- Emission --- Manuel --- N2o --- Nox --- Emission
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Methane. --- Methane --- Nitrates --- Nitrates --- agriculture. --- agriculture --- Gases --- Gases --- Measurement --- Measurement --- Sampling --- Sampling --- Measuring instruments --- Measuring instruments --- methodology --- methodology --- air pollution --- air pollution --- Nonpoint pollution --- Nonpoint pollution --- Nitrogen oxides --- Nitrogen oxides --- Nitrous oxide --- Nitrous oxide --- Cta --- Manuel --- N2o --- Nox --- Emission --- Cta --- Manuel --- N2o --- Nox --- Emission
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Azote --- Nitrogen --- Nitrate --- Nitrates --- Polluant --- pollutants --- Pollution --- Enquête --- surveys --- Modèle --- Models --- 546.172.5 --- 614.71 --- 631.814 --- Nitrous oxide N2O and its derivatives --- Hygiene of the air. Air pollution --- Loss of fertilizer principals. Change in manurial value --- Theses --- 631.814 Loss of fertilizer principals. Change in manurial value --- 614.71 Hygiene of the air. Air pollution
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Forest ecosystems are often disturbed by agents such as harvesting, fire, wind, insects and diseases, and acid deposition, with differing intensities and frequencies. Such disturbances can markedly affect the amount, form, and stability of soil organic carbon in, and the emission of greenhouse gases, including CO2, CH4, and N2O from, forest ecosystems. It is vitally important that we improve our understanding of the impact of different disturbance regimes on forest soil carbon dynamics and greenhouse gas emissions to guide our future research, forest management practices, and policy development. This Special Issue provides an important update on the disturbance effects on soil carbon and greenhouse gas emissions in forest ecosystems in different climate regions.
greenhouse gas emission --- heterotrophic respiration --- Camellia oleifera --- Larix principis-rupprechtii Mayr --- soil microbial residue --- assisted natural regeneration --- soil organic carbon --- soil carbon sequestration --- soil CO2 --- surface soil layer --- landform --- anthropogenic effect --- South Korea --- CO2 effluxes --- storm damage --- microbial properties --- calcareous soil --- land use pattern --- soil total nitrogen --- generation --- tree mortality --- land use types --- forest conversion --- DCD --- carbon source–sink --- stoichiometric ratios --- autotrophic respiration --- N2O --- CO2 emission --- organic carbon mineralization --- CH4 emissions --- clear-cutting --- CO2 production and diffusion --- soil quality --- nitrification inhibitor --- organic carbon accumulation --- climate change mitigation --- global change --- greenhouse gas inventory --- warming --- soil properties --- bacterial community --- sensitivity --- soil characteristics --- forest --- insect outbreak --- biochar --- nitrous oxide --- CO2 --- soil respiration --- land-use change --- decomposition --- soil --- natural forest --- calcareous soils --- greenhouse gas --- forest soils --- karst graben basin --- plantation --- rocky desertification --- fitting parameters --- temperature --- forest disturbance --- microbe --- subtropical forest --- N addition --- carbon stock changes --- IPCC --- next-generation sequencing --- nitrogen --- N2O emissions --- red soils --- CH4 --- coastal wetlands --- CO2 emissions --- stand age --- successive planting --- plum plantation ages
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Oxyde nitreux --- Nitrous oxide --- Cycle de l'azote --- nitrogen cycle --- Dioxyde de carbone --- carbon dioxide --- Sol arable --- Arable soils --- Échange gazeux --- Gas exchange --- Pollution atmosphérique --- air pollution --- 631.416.1 --- 546.172.5 --- 631.814 --- Nitrogen --- Nitrous oxide N2O and its derivatives --- Loss of fertilizer principals. Change in manurial value --- Theses --- 631.814 Loss of fertilizer principals. Change in manurial value --- 631.416.1 Nitrogen --- Flandre
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Pâturages --- Pastures --- Engrais azoté --- nitrogen fertilizers --- Oxyde d'azote --- Nitrogen oxides --- Pollution atmosphérique --- air pollution --- Impact sur l'environnement --- Environmental impact --- Cycle de l'azote --- nitrogen cycle --- Modèle --- Models --- Netherlands --- 631.814 --- 614.71 --- 633.2 --- Loss of fertilizer principals. Change in manurial value --- Hygiene of the air. Air pollution --- Forage grasses. Meadow and pasture grasses --- Theses --- 633.2 Forage grasses. Meadow and pasture grasses --- 614.71 Hygiene of the air. Air pollution --- 631.814 Loss of fertilizer principals. Change in manurial value --- N2O --- Agriculture. --- Grasslands. --- Nitrous oxide. --- Laughing-gas --- Anesthetics --- Grass lands --- Lands, Grass --- Grasses --- Farming --- Husbandry --- Industrial arts --- Life sciences --- Food supply --- Land use, Rural --- Monograph --- Relation plante atmosphere
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Kinetics and reactor modeling for heterogeneous catalytic reactions are prominent tools for investigating and understanding catalyst functionalities at nanoscale and the related rates of complex reaction networks. This book illustrates some examples related to the transformation of simple to more complex feedstocks, including different types of reactor designs, i.e., steady-state, transient plug flow reactors, and TAP reactors for which there is sometimes a strong gap in the operating conditions from ultra-high-vacuum to high-pressure conditions. In conjunction, new methodologies have emerged, giving rise to more robust microkinetics models. As exemplified, they include the kinetics and the dynamics of the reactors and span a large range of length and time scales. The objective of this Special Issue is to provide contributions that can illustrate recent advances and novel methodologies for elucidating the kinetics of heterogeneous reactions and the necessary multiscale approach for optimizing the reactor design. This book is dedicated to postgraduate and scientific researchers, and experts in heterogeneous catalysis. It may also serve as a source of original information for the elaboration of lessons on catalysis for Master students.
microkinetics --- n/a --- internal effectiveness factor --- FTIR spectroscopy --- automation --- power-law --- AEIR method --- promoter --- TAP reactor --- rhodium --- Temkin model --- mechanism analysis --- H2S --- N2O --- catalytic decomposition --- cracking --- 1 --- 2 --- methanol-to-olefins (MTO) --- zeolite --- ZSM-23 --- kinetic model --- pilot-scale fixed-bed reactor --- methane --- effective diffusion coefficient --- SAPO-18 --- kinetics --- alkali metal --- ZSM-5 --- digitalization --- gas-phase oxidation --- kinetic modeling --- temporal analysis of products --- selective oxidation --- Methyl Ethyl Ketone --- amorphous calcium phosphate --- reactor modeling --- HNO3 --- 3-Butadiene --- transient kinetics --- catalytic combustion --- cobalt mixed oxide --- 3-Butanediol dehydration --- ammonia decomposition --- heats of adsorption --- Pd/?-Al2O3 --- SAPO-34 --- Langmuir–Hinshelwood --- hierarchical graphite felts
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