Archaeological Geophysical Prospection in Peatland Environments: case studies and suggestions for future practice

Peatland environments, in contrast to ‘dry-land’ sites, preserve organic material, including anthropogenic objects, because they are anaerobic, and are therefore of great importance to archaeology. Peat also preserves macro- and micro- paleoenvironmental evidence and is the primary resource for understanding past climates and ecology. Archaeological sites often lie within or at the base of wet, deep, homogenous peat rendering them invisible to surface observers. As a result, they most often c..

Inverse kinetic isotope effects in the charge transfer reactions of ammonia with rare gas ions

In the absence of experimental data, models of complex chemical environments rely on predicted reaction properties. Astrochemistry models, for example, typically adopt variants of capture theory to estimate the reactivity...</p

Observational evidence confirms modelling of the long-term integrity of CO2-reservoir caprocks

Anthropogenic CO2 storage, where CO2 is injected into saline geological resevoirs, relies on an impermeable caprock to seal in the CO2, but caprock reaction rates to CO2 acid brines are unclear

The Green River Natural Analogue as a field laboratory to study the long-term fate of CO2 in the subsurface

Understanding the long-term response of CO2 injected into porous reservoirs is one of the most important aspects to demonstrate safe and permanent storage. In order to provide quantitative constraints on the long-term impacts of CO2-charged fluids on the integrity of reservoir-caprock systems we recovered some 300m of core from a scientific drill hole through a natural CO2 reservoir, near Green River, Utah. We obtained geomechanical, mineralogical, geochemical, petrophysical and mineralogical laboratory data along the entire length of the core and from non CO2-charged control samples. Furthermore, we performed more detailed studies through portions of low permeability layers in direct contact with CO2-charged layers. This was done to constrain the nature and penetration depths of CO2-promoted fluid-mineral reaction fronts. The major reactions identified include the dissolution of diagenetic dolomite cements and hematite grain coatings, and the precipitation of ankerite and pyrite and have been used as input for geochemical 1D reactive transport modelling, to constrain the magnitude and velocity of the mineral-fluid reaction front. In addition, we compared geomechanical data from the CO2-exposed core and related unreacted control samples to assess the mechanical stability of reservoir and seal rocks in a CO2 storage complex following mineral dissolution and precipitation for thousands of years. The obtained mechanical parameters were coupled to mineralogy and porosity. Key aim of this work was to better quantify the effect of long-term chemical CO2/brine/rock interactions on the mechanical strength and elastic properties of the studied formations

A Reference High-Pressure CO2\u3c/sub\u3e Adsorption Isotherm for Ammonium ZSM-5 Zeolite: Results of an Interlaboratory Study

© 2018, The Author(s). This paper reports the results of an international interlaboratory study led by the National Institute of Standards and Technology (NIST) on the measurement of high-pressure surface excess carbon dioxide adsorption isotherms on NIST Reference Material RM 8852 (ammonium ZSM-5 zeolite), at 293.15 K (20 °C) from 1 kPa up to 4.5 MPa. Eleven laboratories participated in this exercise and, for the first time, high-pressure adsorption reference data are reported using a reference material. An empirical reference equation nex=d(1+exp[(-ln(P)+a)/b])c, [nex-surface excess uptake (mmol/g), P-equilibrium pressure (MPa), a = −6.22, b = 1.97, c = 4.73, and d = 3.87] along with the 95% uncertainty interval (Uk = 2 = 0.075 mmol/g) were determined for the reference isotherm using a Bayesian, Markov Chain Monte Carlo method. Together, this zeolitic reference material and the associated adsorption data provide a means for laboratories to test and validate high-pressure adsorption equipment and measurements. Recommendations are provided for measuring reliable high-pressure adsorption isotherms using this material, including activation procedures, data processing methods to determine surface excess uptake, and the appropriate equation of state to be used

A Reference High-Pressure CO2\u3c/sub\u3e Adsorption Isotherm for Ammonium ZSM-5 Zeolite: Results of an Interlaboratory Study

© 2018, The Author(s). This paper reports the results of an international interlaboratory study led by the National Institute of Standards and Technology (NIST) on the measurement of high-pressure surface excess carbon dioxide adsorption isotherms on NIST Reference Material RM 8852 (ammonium ZSM-5 zeolite), at 293.15 K (20 °C) from 1 kPa up to 4.5 MPa. Eleven laboratories participated in this exercise and, for the first time, high-pressure adsorption reference data are reported using a reference material. An empirical reference equation nex=d(1+exp[(-ln(P)+a)/b])c, [nex-surface excess uptake (mmol/g), P-equilibrium pressure (MPa), a = −6.22, b = 1.97, c = 4.73, and d = 3.87] along with the 95% uncertainty interval (Uk = 2 = 0.075 mmol/g) were determined for the reference isotherm using a Bayesian, Markov Chain Monte Carlo method. Together, this zeolitic reference material and the associated adsorption data provide a means for laboratories to test and validate high-pressure adsorption equipment and measurements. Recommendations are provided for measuring reliable high-pressure adsorption isotherms using this material, including activation procedures, data processing methods to determine surface excess uptake, and the appropriate equation of state to be used

Symposium on the Scottish labour market

In the post-war period, up to the late 1960s, Britain enjoyed a modicum of unemployment and government policies which were geared to producing Full Employment were considered a success. It was simple - boost demand and more people would find work. But the mid 1970s the economic regency enjoyed by those advocating demand sided policies fell into disrepute as the OPEC nations raised prices dramatically and brought in a new era of both rising prices and unemployment. The laws of economics, which previously had viewed policy decisions as the choice between lower unemployment and higher inflation were now redundant. Both unemployment and inflation were moving in the same direction. The era of stagflation had begun