64 research outputs found

    Presence of Priority Polycyclic Aromatic Hydrocarbons, Chromium, Copper and Lead in Two selected Brownfield Sites in United Kingdom

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    In recent years, concerns about adverse effects of increasing land contamination paralleled with the increasing demand for land has emphasized need for sustainable remediation strategies. Soil samples were collected from two brownfield sites, in Saltley, Birmingham and Swansea, South Wales, United Kingdom and analysed to establish the extent of contamination by priority polycyclic aromatic hydrocarbon (PAH) compounds. Saltley site had a total PAH concentration of 41.0 mg kg-1 with high concentrations of phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene, chrysene and benzo[a]pyrene, total benzo[a]pyrene equivalent value of 6.0 mg kg-1 and total carcinogenic PAH of 19.0 mg kg-1. At the Swansea site, total PAH concentration ranged from 5.0 – 85.0 mg kg-1 with pyrene, fluoranthene, benzo[a]anthracene, chrysene, benzo[a]pyrene as the predominant PAHs, total benzo[a]pyrene equivalent value of 0.9 – 2.0 mg kg-1 and total carcinogenic PAH concentration of 2.6 – 11.0 mg kg-1. Heavy metal concentrations were above the ambient background concentrations for urban/industrial area. Both brownfield sites had a mixture of PAH and heavy metal contamination in varying concentrations with implication for the selection of efficient remedial strategies to enable their redevelopment

    A systematic study of element mobilisation from gas shales during hydraulic fracturing

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    The large quantities of wastewater produced throughout the lifetime of a shale gas well can contain heavy metals and other regulated potentially toxic elements. These can be mobilised from the target formation by some of the additives present in the hydraulic fracturing fluids (HFF). High levels of inorganic geogenic chemicals may pose a hazard to the environment through accidental releases such as spills of untreated wastewater. The concentration of mobilised elements and the hazard they pose is uncertain and is likely dependant on the chemical agents used in HFF, groundwater composition and the trace element content of targeted shale gas formation. Laboratory protocols were developed to investigate the release of inorganic contaminants of potential concern (e.g. As, Co, Cu, Pb, Se) from shale gas formations around the world. Powdered rock samples were leached for up to 360 hours at elevated temperature (80°C) and a range of pressures (1-200 bar), with synthetic HFF and synthetic groundwater (SGW). Elemental concentrations released into solution were generally much higher in the HFF leachates than in the SGW treatments, indicating that the chemical additives in the HFF influenced element mobilisation. SEM and EDX images show substantial mineral etching and precipitation of secondary phases on shale chips leached for 360 hours with HFF at 80°C and ~180 bar when compared to the SGW experiment. Time-series data also show evidence of mineral dissolution and subsequent precipitation of new phases, which resulted in sequestration of a number of trace elements that were initially mobilised into the solution. We also observed that the carbonate content of the unreacted shale sample had a strong control on the final pH of the HFF leachates. This study shows that additives can enhance the release of geogenic chemicals, but also that subsequent precipitation within the fracture system could limit ultimate release to surface

    Customer emotions in service failure and recovery encounters

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    Emotions play a significant role in the workplace, and considerable attention has been given to the study of employee emotions. Customers also play a central function in organizations, but much less is known about customer emotions. This chapter reviews the growing literature on customer emotions in employee–customer interfaces with a focus on service failure and recovery encounters, where emotions are heightened. It highlights emerging themes and key findings, addresses the measurement, modeling, and management of customer emotions, and identifies future research streams. Attention is given to emotional contagion, relationships between affective and cognitive processes, customer anger, customer rage, and individual differences

    Volume I. Introduction to DUNE

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    The preponderance of matter over antimatter in the early universe, the dynamics of the supernovae that produced the heavy elements necessary for life, and whether protons eventually decay—these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our universe, its current state, and its eventual fate. The Deep Underground Neutrino Experiment (DUNE) is an international world-class experiment dedicated to addressing these questions as it searches for leptonic charge-parity symmetry violation, stands ready to capture supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector technical design report (TDR) describes the DUNE physics program and the technical designs of the single- and dual-phase DUNE liquid argon TPC far detector modules. This TDR is intended to justify the technical choices for the far detector that flow down from the high-level physics goals through requirements at all levels of the Project. Volume I contains an executive summary that introduces the DUNE science program, the far detector and the strategy for its modular designs, and the organization and management of the Project. The remainder of Volume I provides more detail on the science program that drives the choice of detector technologies and on the technologies themselves. It also introduces the designs for the DUNE near detector and the DUNE computing model, for which DUNE is planning design reports. Volume II of this TDR describes DUNE\u27s physics program in detail. Volume III describes the technical coordination required for the far detector design, construction, installation, and integration, and its organizational structure. Volume IV describes the single-phase far detector technology. A planned Volume V will describe the dual-phase technology

    Deep Underground Neutrino Experiment (DUNE), far detector technical design report, volume III: DUNE far detector technical coordination

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    The preponderance of matter over antimatter in the early universe, the dynamics of the supernovae that produced the heavy elements necessary for life, and whether protons eventually decay—these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our universe, its current state, and its eventual fate. The Deep Underground Neutrino Experiment (DUNE) is an international world-class experiment dedicated to addressing these questions as it searches for leptonic charge-parity symmetry violation, stands ready to capture supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector technical design report (TDR) describes the DUNE physics program and the technical designs of the single- and dual-phase DUNE liquid argon TPC far detector modules. Volume III of this TDR describes how the activities required to design, construct, fabricate, install, and commission the DUNE far detector modules are organized and managed. This volume details the organizational structures that will carry out and/or oversee the planned far detector activities safely, successfully, on time, and on budget. It presents overviews of the facilities, supporting infrastructure, and detectors for context, and it outlines the project-related functions and methodologies used by the DUNE technical coordination organization, focusing on the areas of integration engineering, technical reviews, quality assurance and control, and safety oversight. Because of its more advanced stage of development, functional examples presented in this volume focus primarily on the single-phase (SP) detector module

    Highly-parallelized simulation of a pixelated LArTPC on a GPU

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    The rapid development of general-purpose computing on graphics processing units (GPGPU) is allowing the implementation of highly-parallelized Monte Carlo simulation chains for particle physics experiments. This technique is particularly suitable for the simulation of a pixelated charge readout for time projection chambers, given the large number of channels that this technology employs. Here we present the first implementation of a full microphysical simulator of a liquid argon time projection chamber (LArTPC) equipped with light readout and pixelated charge readout, developed for the DUNE Near Detector. The software is implemented with an end-to-end set of GPU-optimized algorithms. The algorithms have been written in Python and translated into CUDA kernels using Numba, a just-in-time compiler for a subset of Python and NumPy instructions. The GPU implementation achieves a speed up of four orders of magnitude compared with the equivalent CPU version. The simulation of the current induced on 10^3 pixels takes around 1 ms on the GPU, compared with approximately 10 s on the CPU. The results of the simulation are compared against data from a pixel-readout LArTPC prototype

    Session 3-A: Longing in the Work of C.S. Lewis

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    C.S. Lewis: Sixty Years of Letters: A Thematic Overview of His Passions - Jessica Shaver Renshaw Rather than speaking about C.S. Lewis, we will let Jack speak about himself through his letters: what he loved, such as books, seasons/weather, walking tours, bathing, Ireland, animals, convalescence, Joy, and writing; what he loathed: writing letters, Americans, cities, TV, newspapers, movies, modern novels/poetry/theology; what he feared; what he didn\u27t understand; and what he regretted, as well as his descriptions of what he looked like, what he did well, what he did badly. I will force myself with Great Difficulty (because of all the choice bits I will have to leave out) to limit these tastes of his sixty-year three-volume, 3,600 page, 9-1/2 pound correspondence to what can be savored in twenty minutes! \u27Parascriptural\u27 Revelation in C.S. Lewis - J.C. Calhoun In the theology of C.S. Lewis, God is rather verbose and unrestrained in the manners and means of communication. God must be understood as the speaking God; anything less will not do Him justice. The few extant works about Lewis\u27s theology of revelation focus on scripture, and though this is an important topic, one cannot understand it properly without first understanding how God speaks in general. This paper explicates his epistemology as a foundation, and then under the rubric of basic communication theory (author, text, recipient, re-texting), presents eleven \u27parascriptural\u27 paths through which God speaks as mentioned in Lewis\u27s writings. The term \u27parascriptural\u27 - \u27para\u27 in the sense of \u27beside\u27 or \u27alongside of\u27 - is used instead of \u27General Revelation\u27 because the traditional division between General and Special Revelation forces categories upon Lewis that are alien to his thought. After presenting these eleven paths, they are categorized and related back to his epistemology. The paper then finishes as it should, with tantalizing questions about what this means for understanding Lewis and why it is important in our own lives. Moderator: Robert Moore-Jumonvill

    Acetohydroxamatoiron(III) complexes : thermodynamics of formation and temperature dependent speciation.

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    Studies of the thermodynamics of formation of the acetohydroxamatoiron(III) complexes were carried out in acidic media at temperatures ranging from 293 to 323 K. Through the isolation of the unique UV-visible spectra of all three complexes, it was possible to determine their formation constants and deduce enthalpies and entropies of formation as well as their molar absorptivities. The enthalpies of formation of the mono-, bis- and trisacetohydroxamatoiron(III) complexes were found to be -56.4, -17.09 and +19.74 kJ.mol(-1), respectively. Following the determination of the enthalpy and entropy of formation of these complexes, speciation diagrams were calculated for the complexes at temperatures ranging from 293 to 323 K

    Modeling Genome Evolution with a DSEL for Probabilistic Programming

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