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Untersuchungen zur Feinsedimentdynamik unter Turbulenzeinfluss

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Book Series: Dissertationsreihe am Institut für Hydromechanik der Universität Karlsruhe / Universität Karlsruhe (TH), Institut für Hydromechanik ISSN: 14394111 ISBN: 9783866442054 Year: Volume: 2007/2 Pages: VI, 129 p. DOI: 10.5445/KSP/1000007360 Language: GERMAN
Publisher: KIT Scientific Publishing
Subject: General and Civil Engineering
Added to DOAB on : 2019-07-30 20:02:00
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In der vorliegenden Arbeit wurde mit der Entwicklung einer differentiellen Turbulenzsäule das advektionsfreie Turbulenzprofil einer offenen Gerinneströmung im Labor nachgebildet. Hierin konnten die Prozesse der Feinsedimentdynamik nachgebildet und gemessen werden. Die Ergebnisse beschreiben den Prozessablauf in der Feinsedimentdynamik und dienten als Grundlage für die Entwicklung und Validierung eines Modells zur Bilanzierung der Feinsedimentdynamik in der Wassersäule.

Near-critical and supercritical hydrothermal flow synthesis of metal oxide nanoparticles and hybrid metal oxide nanoparticles presenting clickable anchors

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ISBN: 9783731502623 Year: Pages: XIX, 259 p. DOI: 10.5445/KSP/1000043063 Language: ENGLISH
Publisher: KIT Scientific Publishing
Subject: Technology (General)
Added to DOAB on : 2019-07-30 20:02:00
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The continuous hydrothermal flow synthesis of functionalized and non-functionalized nanoparticle dispersions was pursued. Besides improving the understanding of the relationship between process variables and the resulting nanoparticle dispersions, the usability of this process was extended by introducing clickable organic modifiers, a step toward the development of a convenient and versatile process for the synthesis of metal oxide nanoparticles with universal anchors on their surface.

Le mercure en Amazonie : Rôle de l’homme et de l’environnement, risques sanitaires

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ISBN: 9782709917698 Year: DOI: 10.4000/books.irdeditions.2519 Language: French
Publisher: IRD Éditions
Subject: Science (General) --- Social Sciences
Added to DOAB on : 2017-06-09 10:17:46
License: OpenEdition Licence for Books

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Cet ouvrage est le fruit de l’une des premières « expertises collégiales » coordonnées par l’Institut de recherche pour le développement (IRD). Il fait le bilan des connaissances sur la présence, préoccupante, du mercure en Amazonie, sur ses effets sur l’environnement et la santé. Il se conclut par un certain nombre de recommandations opérationnelles. Il existe deux modes spécifiques de contamination humaine par le mercure : l’exposition des travailleurs de l’or (orpailleurs ou raffineurs) aux vapeurs de mercure dégagées lors des opérations d’enrichissement du minerai aurifère et de purification des lingots ; l’exposition de la population à un dérivé du mercure, le méthylmercure, principalement par la consommation de poissons eux-mêmes contaminés. Le premier mode, direct, de contamination peut entraîner des troubles de la santé du fait d’expositions prolongées et répétées. Ceux-ci concernent les voies respiratoires, le système gastro-intestinal et le système nerveux central, ce dernier pouvant être l’objet d’altérations irréversibles. Le caractère souvent clandestin et précaire des activités d’orpaillage ne favorise pas l’usage de techniques qui éviteraient ou du moins réduiraient cette contamination. La seconde forme d’exposition est beaucoup plus difficile encore à maîtriser. La méthylation du mercure, issu de l’orpaillage mais aussi contenu dans les sols à l’état « naturel », relève d’activités bactériennes dans des milieux aquatiques privés d’oxygène et riches en matière organique. L’exportation du mercure est facilitée par la déforestation – les sols dénudés favorisent sa libération – et par l’aptitude de ce métal à se complexer aux fines suspensions argilo-organiques véhiculées par les eaux. La contamination des poissons est l’étape suivante de la chaîne de transfert vers l’homme : comme, pour beaucoup de populations amazoniennes, leur consommation représente la source essentielle de protéines, elle constitue un agent d’exposition quasi quotidienne au méthylmercure dans l’ensemble de l’Amazonie et non dans les seules régions d’orpaillage. Cette imprégnation continue entraîne essentiellement l’apparition, tant chez l’adulte que chez l’enfant, d’atteintes neurologiques sévères, plus graves encore chez le fœtus au moment de la formation des organes. À partir de ces constats, un certain nombre de recommandations sont avancées : la mise en place d’un observatoire amazonien de surveillance, la création d’une structure d’encadrement de l’orpaillage, l’usage généralisé d’équipements de protection contre les vapeurs de mercure, diverses mesures techniques destinées à réduire l’impact du mercure dans l’environnement, une meilleure diffusion de l’information de base sur les risques encourus, l’adoption d’habitudes alimentaires prévenant l’exposition régulière au méthylmercure, une amélioration des suivis sanitaires.

Sediment Transport in Coastal Waters

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ISBN: 9783038978442 9783038978459 Year: Pages: 284 DOI: 10.3390/books978-3-03897-845-9 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Oceanography
Added to DOAB on : 2019-04-25 16:37:17
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The interface of 440,000 km long coastline in the world is subject to global change, with an increasing human pressure (land use, buildings, sand mining, dredging) and increasing population. Improving our knowledge on involved mechanisms and sediment transport processes, monitoring the evolution of sedimentary stocks and anticipating changes in littoral and coastal zones is essential for this purpose. The special issue of Water on “Sediment transport in coastal waters” gathers thirteen papers which introduce the current revolution in the scientific research related to coastal and littoral hydrosedimentary dynamics, and reflect the diversity of concerns on which research in coastal sediment transport is based, and current trends — topics and preferred methods — to address them.

Keywords

suspended sediment --- sediment transport --- coastal hydraulics --- Mekong --- river plume --- monsoon --- mathematical model --- geochemical map --- particle transfer process --- tidal current --- analysis of variance (ANOVA) --- Cluster analysis --- Mahalanobis’ generalized distances --- Seto Inland Sea --- East Coast Low --- nearshore processes --- coastal erosion --- coastal management --- climate change --- numerical modelling --- Southeast Australia --- soil erosion --- SWAT --- water scarcity --- sediment transport modelling --- Tafna catchment --- North Africa --- suspended sediment --- sediment transport --- lagoon --- geochemistry --- Ni mining --- sediment trap --- hydrodynamics --- New Caledonia --- dry season --- Senegal River delta --- Langue de Barbarie spit --- delta vulnerability --- river-mouth migration --- spit breaching --- ERA hindcast waves --- longshore sediment transport --- Vietnam --- South China Sea --- erosion --- recovery --- storminess --- winter monsoon --- typhoons --- shoreline --- waves forcing --- storms --- resilience --- post-storm recovery --- Bight of Benin --- seasonal cycle --- trend --- sand-mud mixture erosion --- numerical modelling --- non-cohesive to cohesive transition --- remote sensing reflectance --- turbidity --- seagrass beds --- bed shear stress --- fresh water runoff --- oceanic water intrusion --- suspended particulate matter --- aggregates --- flocculation --- biomass --- sediment --- turbidity --- remote-sensing --- MODerate Resolution Imaging Spectroradiometer (MODIS) --- Support Vector Regression (SVR) --- oligotrophic lagoon --- bathymetry --- reflectance --- seabed colour --- coral reef --- New Caledonia --- sediment transport --- cohesive sediments --- non cohesive sediments --- sand --- mud --- coastal erosion --- sedimentation --- morphodynamics --- suspended particulate matter --- bedload

Marine Geomorphometry

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ISBN: 9783038979548 / 9783038979555 Year: Pages: 400 DOI: 10.3390/books978-3-03897-955-5 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- General and Civil Engineering
Added to DOAB on : 2019-06-26 08:44:07
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Geomorphometry is the science of quantitative terrain characterization and analysis, and has traditionally focused on the investigation of terrestrial and planetary landscapes. However, applications of marine geomorphometry have now moved beyond the simple adoption of techniques developed for terrestrial studies, driven by the rise in the acquisition of high-resolution seafloor data and by the availability of user-friendly spatial analytical tools. Considering that the seafloor represents 71% of the surface of our planet, this is an important step towards understanding the Earth in its entirety.This volume is the first one dedicated to marine applications of geomorphometry. It showcases studies addressing the five steps of geomorphometry: sampling a surface (e.g., the seafloor), generating a Digital Terrain Model (DTM) from samples, preprocessing the DTM for subsequent analyses (e.g., correcting for errors and artifacts), deriving terrain attributes and/or extracting terrain features from the DTM, and using and explaining those terrain attributes and features in a given context. Throughout these studies, authors address a range of challenges and issues associated with applying geomorphometric techniques to the complex marine environment, including issues related to spatial scale, data quality, and linking seafloor topography with physical, geological, biological, and ecological processes. As marine geomorphometry becomes increasingly recognized as a sub-discipline of geomorphometry, this volume brings together a collection of research articles that reflect the types of studies that are helping to chart the course for the future of marine geomorphometry.

Keywords

bedforms --- forage fish --- Pacific sand lance --- sediment habitats --- bathymetry --- currents --- seabed mapping --- marine geology --- submarine topography --- marine geomorphology --- terrain analysis --- multibeam echosounder --- bathymetry --- DEM --- satellite imagery --- multi beam echosounder --- filter --- geomorphology --- coral reefs --- Acoustic applications --- object segmentation --- seafloor --- underwater acoustics --- Cretaceous --- Cenomanian–Turonian --- paleobathymetry --- paleoclimate --- paleoceanography --- reconstruction --- simulation --- shelf-slope-rise --- geomorphometry --- GIS --- spatial scale --- spatial analysis --- terrain analysis --- seafloor geomorphometry --- domes --- volcanoes --- digital elevation models (DEMs) --- Canary Basin --- Atlantic Ocean --- cold-water coral --- carbonate mound --- habitat mapping --- spatial prediction --- image segmentation --- geographic object-based image analysis --- random forest --- accuracy --- confidence --- global bathymetry --- Seabed 2030 --- Nippon Foundation/GEBCO --- seafloor mapping technologies --- seafloor mapping standards and protocols --- benthic habitats --- shelf morphology --- eastern Brazilian shelf --- geomorphometry --- terrain analysis --- bathymetry --- surface roughness --- benthic habitat mapping --- python --- geomorphology --- submerged glacial bedforms --- deglaciation --- sedimentation --- multibeam --- acoustic-seismic profiling --- swath geometry --- multibeam spatial resolution --- integration artefacts --- Multibeam bathymetry --- benthic habitat mapping --- multiscale --- Random Forests --- pockmarks --- automated-mapping --- ArcGIS --- Glaciated Margin --- North Sea --- Malin Basin --- Barents Sea --- bathymetry --- thalwegs --- canyons --- Alaska --- Bering Sea --- multibeam sonar --- carbonate banks --- semi-automated mapping --- polychaete --- Northwestern Australia --- Oceanic Shoals Australian Marine Park --- Bonaparte Basin --- Timor Sea --- bathymetry --- digital terrain analysis --- geomorphometry --- geomorphology --- habitat mapping --- marine remote sensing

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