Multiphase Thermohaline Convection in the Earth's Crust: I. A New Finite Element - Finite Volume Solution Technique Combined With a New Equation of State for NaCl-H2O

We present a new finite element - finite volume (FEFV) method combined with a realistic equation of state for NaCl-H2O to model fluid convection driven by temperature and salinity gradients. This method can deal with the nonlinear variations in fluid properties, separation of a saline fluid into a high-density, high-salinity brine phase and low-density, low-salinity vapor phase well above the critical point of pure H2O, and geometrically complex geological structures. Similar to the well-known implicit pressure explicit saturation formulation, this approach decouples the governing equations. We formulate a fluid pressure equation that is solved using an implicit finite element method. We derive the fluid velocities from the updated pressure field and employ them in a higher-order, mass conserving finite volume formulation to solve hyperbolic parts of the conservation laws. The parabolic parts are solved by finite element methods. This FEFV method provides for geometric flexibility and numerical efficiency. The equation of state for NaCl-H2O is valid from 0 to 750°C, 0 to 4000bar, and 0-100 wt.% NaCl. This allows the simulation of thermohaline convection in high-temperature and high-pressure environments, such as continental or oceanic hydrothermal systems where phase separation is commo

Multiphase Thermohaline Convection in the Earth's Crust: II. Benchmarking and Application of a Finite Element - Finite Volume Solution Technique with a NaCl-H2O Equation of State

We present the benchmarking of a new finite element - finite volume (FEFV) solution technique capable of modeling transient multiphase thermohaline convection for geological realistic p-T-X conditions. The algorithm embeds a new and accurate equation of state for the NaCl-H2O system. Benchmarks are carried out to compare the numerical results for the various component-processes of multiphase thermohaline convection. They include simulations of (i) convection driven by temperature and/or concentration gradients in a single-phase fluid (i.e., the Elder problem, thermal convection at different Rayleigh numbers, and a free thermohaline convection example), (ii) multiphase flow (i.e., the Buckley-Leverett problem), and (iii) energy transport in a pure H2O fluid at liquid, vapor, supercritical, and two-phase conditions (i.e., comparison to the U.S. Geological Survey Code HYDROTHERM). The results produced with the new FEFV technique are in good agreement with the reference solutions. We further present the application of the FEFV technique to the simulation of thermohaline convection of a 400°C hot and 10 wt.% saline fluid rising from 4km depth. During the buoyant rise, the fluid boils and separates into a high-density, high-salinity liquid phase and a low-density, low-salinity vapor phas

Räumliche Aspekte des Lehrkräftearbeitsmarkts am Beispiel des ostdeutschen Flächenlandes Mecklenburg-Vorpommern

Durch den „Geburtenschock“ nach der Wende und den dadurch ausgelösten Rückgang der Schüler:innenzahlen wurden in den neuen Bundesländern in der Folge kaum Nachwuchslehrkräfte eingestellt. Entsprechend weisen diese Bundesländer gegenüber den alten einen verschobenen Trend in der Altersstruktur der Lehrkräfte auf und mittlerweile erreichen viele der Lehrkräfte die Regelaltersgrenze. In Mecklenburg-Vorpommern zeigt sich die Alterung der Schulkollegien besonders deutlich. Zudem ist das Bundesland stark durch ländliche Räume geprägt, die ebenso wie die Städte um Nachwuchslehrkräfte werben. Im Beitrag wird anhand amtlicher Daten zu Lehrkräftealtersgruppen aufgezeigt, dass jüngere Lehrer:innen auch unter Berücksichtigung ausgewählter Schularten und Fächer bevorzugt in Städten tätig sind. Diese Entwicklung verschärft den Lehrkräftemangel im ländlichen Raum und unterstreicht, dass der Ersatzbedarf regional betrachtet werden sollte. Es werden Maßnahmen diskutiert, die (angehende) Lehrkräfte für eine Tätigkeit im ländlichen Raum werben und dort halten können. (DIPF/Orig.

Comparison of Hop Derived Humulone Constituents in Beer Using UV-Vis, HPLC, and LC-MS

Lupulones and humulones are two families of compounds derived from the hop flower (Humulus lupulus), utilized in brewing beer. Isohumulones are produced during the boiling process by isomerization reactions of humulones and are the primary bittering compounds in beer. The concentration in parts per million (ppm) of isohumulone is reported as IBU (International Bittering Units). Measurement of these compounds is valuable to brewers, but is confounded by other constituents in beer which may also absorb at the 275nm wavelength in UV-Vis spectrometry, the industry standard method. 25 samples were measured using UV-Vis, then analyzed by High Precision Liquid Chromatography (HPLC) and HPLC-Mass Spectrometry (LC-MS). Results were varied with respect to reported IBU. Of note, a sample containing an adjunct had much higher 275nm absorbance than expected, absent when eluted through HPLC, suggesting a falsely higher reading than actual due to interference by the adjunct

D3.5 Report on ECO social network integration features

This document describes how integrations with social networks are being developed in ECO platforms. With these new features, participants will be able to share results and other contents through Facebook, Twitter, Google plus.ICT Policy Support Programme as part of the Competitiveness and Innovation framework Programme (CIP) - grant number 62112

D3.2b Integration Roadmap

The objective of this document is to expose the sequence of steps in time (roadmap) for the integration of the different elements that form the architecture of ECOICT Policy Support Programme as part of the Competitiveness and Innovation framework Programme (CIP) - grant number 62112

D3.1 Validation of technical specifications of ECO modules

The objective of this document is to list the most important technical specifications of each MOOC platform that will be integrated in the overall ECO architecture. The objective of this particular task is to carry out analysis of all the technical specifications of each of the modules/platforms that are to be integrated in the global ECO platform. Once integration will be done, an Open Data exposure solution will be implemented by means of integrating an Open Data Catalog platform such as CKAN.ICT Policy Support Programme as part of the Competitiveness and Innovation framework Programme (CIP) - grant number 62112

Oxygen and hydrogen isotope fractionation in serpentine–water and talc–water systems from 250 to 450°C, 50 MPa

Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Geochimica et Cosmochimica Acta 73 (2009): 6789-6804, doi:10.1016/j.gca.2009.07.036.Oxygen and hydrogen isotope fractionation factors in the talc-water and serpentine-water systems have been determined by laboratory experiment from 250 to 450°C at 50 MPa using the partial exchange technique. Talc was synthesized from brucite + quartz, resulting in nearly 100% exchange during reaction at 350 and 450°C. For serpentine, D-H exchange was much more rapid than 18O-16O exchange when natural chrysotile fibers were employed in the initial charge. In experiments with lizardite as the starting charge, recrystallization to chrysotile enhanced the rate of 18O-16O exchange with the coexisting aqueous phase.This work was supported by NSF Grants OCE-9313980 to the Woods Hole Oceanographic Institution and OCE-9820287 to Bridgewater State College (BSC)