Experimental Na-K distribution between amphiboles and aqueous chloride solutions, and a mixing model along the richterite – K-richterite join     

Rolf Zimmermann  M. Gottschalk  Wilhelm Heinrich  Gerhard Franz 《Contributions to Mineralogy and Petrology》1997,126(3):252-264

The cation exchange equilibrium has been investigated by hydrothermal experiments at 700 and 800°C at 200 MPa. To avoid equilibration problems of conventional exchange experiments, we synthesized amphiboles with an excess fluid allowing exchange between solid and fluid during the experiment. The exchangeable cations Na and K were provided as excess 1 to 2n chloridic solution. These exchange syntheses can be described by the reaction equation with ^(aq) for hydroxides and chlorides in aqueous solutions and _{( s )} and _{( p )}?=?start and product fluid. The amphiboles grew in presence of the exchange fluid and adjusted their stoichiometry in equilibrium with the fluid phase. The solid products consist of more than 99% amphibole (Na,K-richterite_ss) with traces of diopside and quartz. The amphiboles are up to 1?mm long and often ≈ 40 μm thick. Detailed EMP- and HRTEM-observations show that they are chemically homogeneous and structurally wellordered. The experimental results give consistent phase relations in the reciprocal ternary system Na-richterite–K-richterite–NaCl–KCl. We analysed the product fluid with AAS- and ICP-methods. The Na-K distribution coefficients between fluid and amphiboles of the richterite–K-richterite join are close to unity at 700°C and 800°C at 200 MPa. Small systematic deviations are explained by a symmetric solution model for the A-position of the amphiboles. Using ideal mixing for H₂O-NaCl-KCl fluids, a mixing model for the system richterite–K-richterite is presented. We suggest that the composition of richterite solid solutions can be used as a sensor for NaCl/KCl-ratios in metamorphic fluids.  相似文献   

Regional vulnerability assessment for debris flows in China—a CWS approach     

Mingtao Ding  Micha Heiser  Johannes Hübl  Sven Fuchs 《Landslides》2016,13(3):537-550

Based on former conceptual models of vulnerability, this paper aims to improve the quantitative model for regional vulnerability assessment by analyzing in-depth the relation between vulnerability, exposure, coping capacity, and resilience. Taking the mountain settlements in the upper reaches of Min River, China, as a case study, the method of Contributing Weight Superposition (CWS) is applied in establishing both a model and a system for the vulnerability assessment of elements at risk. The CWS approach consists of 13 index factors including population, economic and road densities, building and farmland coverage, hazard-affected areas, urbanization rate, and GDP per capita. Accordingly, a debris flow hazard vulnerability zoning map was obtained and the assessment results show that the distribution of high and comparatively high vulnerability zones, where economic activities are considerably high, has a close correlation to the topography of the catchment and population characteristics. The results thus may serve as a pertinent guidance for settlement relocation, population distribution readjustment, and management to prevent and reduce hazards in the upper reaches of Min River and beyond.  相似文献   

Surface hardness as a proxy for weathering behaviour of limestone heritage: a case study on dated headstones on the Isle of Portland,UK     

K. Wilhelm  H. Viles  O. Burke  J. Mayaud 《Environmental Earth Sciences》2016,75(10):931

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Modular development of an inline monitoring system for waterborne pathogens in raw and drinking water     

Daniel Karthe  Ole Behrmann  Verena Blättel  Dennis Elsässer  Christian Heese  Matthias Hügle  Frank Hufert  Andreas Kunze  Reinhard Niessner  Johannes Ho  Buren Scharaw  Matthias Spoo  Andreas Tiehm  Gerald Urban  Silvia Vosseler  Thomas Westerhoff  Gregory Dame  Michael Seidel 《Environmental Earth Sciences》2016,75(23):1481

The state-of-the-art monitoring of drinking water hygiene is based on the cultivation and enumeration of indicator bacteria. Despite its proven reliability, this approach has the disadvantages of being (a) relatively slow and (b) limited to a small number of indicator bacteria. Ideally, alternative methods would be less time-consuming while providing information about a larger set of hygienically relevant microorganisms including viruses. In this paper, we present insights into the design of a modular concentration and detection system for bacteria, bacteriophages and viruses. Following further validation, this or similar techniques have the potential to extend and speed up the monitoring of raw and drinking water hygiene in the future. The system consists of different modules for the concentration of microorganisms, an amplification and detection unit that includes a module for the differentiation between live and dead microorganisms, and an automated system for decision support and self-diagnosis. The ongoing testing under controlled laboratory conditions and real-life conditions in the water supply industry yields further system improvements. Moreover, the increased sensitivity and broader range of microbiological parameters emphasize the need for a reconsideration of the currently used criteria for the assessment of (drinking) water hygiene.  相似文献   

Real-time raster projection for web maps     

Bernhard Jenny  Bojan Šavrič  Johannes Liem 《International Journal of Digital Earth》2016,9(3):215-229

The virtual globe is the default visualization for Digital Earth applications, but it can only show one half of the Earth. This article introduces user-adjustable, on-the-fly projection of georeferenced raster images for web mapping and web GIS applications. This technique allows users to center a map on arbitrary locations, while still seeing the entire Earth surface. Modern web mapping libraries can apply map projection transformations to vector data in the browser, but they do not currently support the projection of raster images at interactive frame rates. We use the cross-platform WebGL (Web Graphics Library) graphics pipeline for hardware-accelerated projection of raster data in web browsers. Two algorithmic techniques – inverse per-fragment projection, and combined forward per-triangle and inverse per-fragment projection – for georeferenced raster imagery are documented. The resulting raster maps combine the ease of use and flexibility of interactive virtual globes with the ability to show the entire Earth. The adjustable projection of raster imagery allows users to observe global phenomena that are difficult to visualize on virtual globes or traditional maps with static projections.  相似文献   

Zur Tektonik des nördlichen Hegaus     

Wilhelm F. Schmidt 《International Journal of Earth Sciences》1951,39(1):143-147

Ohne Zusammenfassung  相似文献   

Eine Sammlung zur Erläuterung des «Windschliffes»     

Wilhelm Delhaes 《International Journal of Earth Sciences》1915,6(4-6):202-206

Ohne ZusammenfassungDer Verfasser ist in der Nacht vom 25./26. September 1915 in der Champagne gefallen.  相似文献   

A. Unter der Redaktion der Geologischen Vereinigung     

Wilhelm Salomon 《International Journal of Earth Sciences》1914,5(7):478-480

Ohne Zusammenfassung  相似文献   

Zur Entstehung der Kantenkiesel     

Geh. San.-Rat Dr. Wilhelm Pfannkuch 《International Journal of Earth Sciences》1920,10(4-8):112-117

Ohne Zusammenfassung  相似文献   

Mineralogie,Geologie, Lagerstättenlehre     

Wilhelm Petrascheck 《International Journal of Earth Sciences》1934,25(1):73-74

Ohne Zusammenfassung  相似文献