The greenhouse gas (GHG) emissions associated with aquatic carbon removal during drinking water treatment

Peatlands and other terrestrial ecosystems export large amounts of dissolved organic carbon (DOC) to freshwater ecosystems. In catchments used for supplying drinking water, water treatment works (WTWs) can remove large quantities of this organic matter, and can therefore play a unique modifying role in DOC processing and associated greenhouse gas (GHG) emissions within the fluvial system. During this study we quantified the GHG emissions due to processes associated with carbon (C) removal during water treatment at four contrasting WTWs in the UK. Our results demonstrate that the removal of DOC from raw water supplies via coagulation, leading to the formation of sludge, usually makes it less susceptible to short-term oxidation when compared to DOC remaining in the fluvial system. Although this could be considered a means of reducing CO2 emissions from waterborne carbon, the current practise of land spreading of sludge is unlikely to represent a long-term C sink and therefore water treatment probably only delays the rate at which fluvial C re-enters the atmosphere. Furthermore, we estimate that indirect CO2 missions resulting from electricity use during water treatment, together with the use of chemicals and CO2 degassing from the water during treatment, far outweigh any potential CO2 reductions associated with DOC removal. Thus, the post-treatment handling of sludge has the potential to mitigate, but not to negate, GHG emissions associated with water treatment processes

From ‘Techniums’ to ‘emptiums’: the failure of a flagship innovation policy in Wales

This paper examines the use of European Union Structural Funds to support the development of innovation policy within Wales during the period 2000–06. Drawing on data from the Welsh government and interviews with key stakeholders, it focuses specifically on the Technium programme, a high-profile technology-based innovation intervention that took a predominantly supply-side approach to supporting innovation, resulting in its eventual failure. Consistent within this is an analysis of the efficacy of supply-side policies using European Union funds to support research and development activities to aid economic growth in peripheral, weaker regions

A study and experiment plan for digital mobile communication via satellite

The viability of mobile communications is examined within the context of a frequency division multiple access, single channel per carrier satellite system emphasizing digital techniques to serve a large population of users. The intent is to provide the mobile users with a grade of service consistant with the requirements for remote, rural (perhaps emergency) voice communications, but which approaches toll quality speech. A traffic model is derived on which to base the determination of the required maximum number of satellite channels to provide the anticipated level of service. Various voice digitalization and digital modulation schemes are reviewed along with a general link analysis of the mobile system. Demand assignment multiple access considerations and analysis tradeoffs are presented. Finally, a completed configuration is described

Transformations in DOC along a source to sea continuum; impacts of photo-degradation, biological processes and mixing

Peatlands export significant amounts of dissolved organic carbon (DOC) to freshwaters, but the quantity of DOC reaching marine environments is typically less than the input to the fluvial system due to processing within the water column. Key removal processes include photo-chemical degradation, and heterotrophic bacterial respiration. In this study we examined these processes using 14C-labelled DOC to quantify the extent of DOC breakdown and to determine its fate following irradiation under controlled laboratory conditions. We examined the influence of microbial processes occurring within the water column, the potential role of stream-bed biofilms, and the possible modifying effects of downstream mixing, as DOC in water from the peatland encounters runoff from upland mineral soils (“Mountain”), nutrient-rich runoff from agricultural soils, and seawater in an estuary. Our results demonstrated conservative mixing of DOC from Peatland and Mountain waters but interactive effects when Peatland water was mixed with Agricultural and Estuary waters and exposed to solar radiation. The mixing of Peatland and Agricultural waters led to net DOC production, suggesting that DOC was only partially degraded by solar radiation and that the products of this might have fuelled autotrophic microbial growth in the samples. The mixing of Peatland water with saline estuary water resulted in net DOC loss following irradiation, suggesting a role for sunlight in enhancing the flocculation of DOC to particulate organic carbon (POC) in saline environments

Self-control tames the coupling of reactive radicals

Highly reactive or unstable chemical reagents are challenging to prepare, store, and safely handle, so chemists frequently generate them in situ from convenient precursors. In an ideal case, the rate of release of the reagent would be matched to the rate of its “capture” in the desired chemical reaction, thereby preventing the reagent from accumulating and minimizing any opportunity for decomposition. However, this synchronization is rarely achieved or even attempted: The rate of release is usually dictated by the conditions of the reaction (1), rather than being regulated by capture of the reagent. In this issue, Tellis et al. (2) on page 433 and Zuo et al. (3) on page 437 independently report the use of iridium photocatalysis (4, 5) to supply highly reactive radical coupling partners (R⋅) to a nickel-catalyzed carbon-carbon bond-forming process (see the figure). Intriguingly, the two points of contact between the iridium and nickel cycles enforce autoregulated release of the radical, ensuring its efficient capture by nickel rather than its decomposition via other pathways

Velocity-conductivity relations for cratonic lithosphere and their application : example of Southern Africa

Author Posting. © American Geophysical Union, 2013. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry, Geophysics, Geosystems 14 (2013): 806–827, doi:10.1002/ggge.20075.Seismic velocity is a function of bulk vibrational properties of the media, whereas electrical resistivity is most often a function of transport properties of an interconnected minor phase. In the absence of a minor conducting phase then the two should be inter-relatable primarily due to their sensitivity to temperature variation. We develop expressions between shear wave velocity and resistivity for varying temperature, composition, and water content based on knowledge from two kimberlite fields: Jagersfontein (Kaapvaal Craton) and Gibeon (Rehoboth Terrane). We test the expressions through comparison between a new high-resolution regional seismic model, derived from surface wave inversion of earthquake data from Africa and the surrounding regions, and a new electrical image from magnetotelluric (MT) data recorded in SAMTEX (Southern African Magnetotelluric Experiment). The data-defined robust linear regression between the two is found to be statistically identical to the laboratory-defined expression for 40 wt ppm water in olivine. Cluster analysis defines five clusters that are all geographically distinct and tectonically relate to (i) fast, cold, and variably wet Kaapvaal Craton, (ii) fast and wet central Botswana, (iii) slow, warm, and wet Rehoboth Terrane, (iv) moderately fast, cold, and very dry southernmost Angola Craton, and (v) slow, warm, and somewhat dry Damara Belt. From the linear regression expression and the MT image we obtain predicted seismic velocity at 100 km and compare it with that from seismic observations. The differences between the two demonstrate that the linear relationship between Vs and resistivity is appropriate for over 80% of Southern Africa. Finally, using the regressions for varying water content, we infer water content in olivine across Southern Africa.We wish to again acknowledge the three main funding agencies, the U.S. National Science Foundation’s Continental Dynamics Program (grant EAR0455242 to RLE), the South African Department of Science and Technology (grant to South African Council for Geoscience), and Science Foundation Ireland (grant 05/RGP/GEO001 to AGJ), for their support. Industry support for SAMTEX from De Beers Group Services, BHP Billiton and Rio Tinto Mining and Exploration resulted in a program far more extensive than originally conceived. S.F. has been supported by the NERC New Investigator grant NE/G000859/1. M.M. wishes to thank Science Foundation Ireland (grant 08/RFP/GEO1693 SAMTEX to AGJ) for support. J.F. wishes to thank Enterprise Ireland (grant Topo-Med to AGJ), Science Foundation Ireland (grant 10/IN.1/I3022 IRETHERMto AGJ), and the JAE-DOC Programme from Spanish CSIC, cofunded by FSE for support.2013-10-0

Tablet PCs in schools: Case study report: A report for Becta by the Open University

The publication provides an analysis of twelve case studies involving schools in England that were using Tablet PCs. The analysis is complemented by brief individual reports describing aspects of how each of these schools was using Tablet PCs

The Effect of Weak Interactions on the Ultra-Relativistic Bose-Einstein Condensation Temperature

We calculate the ultra-relativistic Bose-Einstein condensation temperature of a complex scalar field with weak lambda Phi^4 interaction. We show that at high temperature and finite density we can use dimensional reduction to produce an effective three-dimensional theory which then requires non-perturbative analysis. For simplicity and ease of implementation we illustrate this process with the linear delta expansion.Comment: Latex2e, 12 pages, three eps figures, replacement with additional discussion and extra figur