42,094 research outputs found

    Diamondoid diacids ('O4' species) in oil sands process-affected water.

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    RATIONALE: As a by-product of oil sands extraction, large volumes of oil sands process water (OSPW) are generated, which are contaminated with a large range of water-soluble organic compounds. The acids are thought to be derived from hydrocarbons via natural biodegradation pathways such as α- and β-oxidation of alkyl substituents, which could produce mono- and diacids, for example. However, while several monoacids ('O2' species) have been identified, the presence of diacids (i.e. 'O4' species) has only been deduced from results obtained via Fourier transform infrared (FTIR) spectroscopy, Fourier transform ion cyclotron resonance high-resolution mass spectrometry (FTICR-HRMS) and nuclear magnetic resonance ((1)H-NMR) spectroscopy and the structures have never been confirmed. METHODS: An extract of an OSPW from a Canadian tailings pond was analysed and the retention times and the electron ionization mass spectra of some analytes were compared with those of bis-methyl esters of authentic diacids by gas chromatography × gas chromatography/time-of-flight mass spectrometry (GCxGC/TOFMS) in nominal and accurate mass configurations. RESULTS: Two diamondoid diacids (3-carboxymethyladamantane-1-carboxylic acid and adamantane-1,3-dicarboxylic acid) were firmly identified as their bis-methyl esters by retention time and mass spectral matching and several other structural isomers were more tentatively assigned. Diacids have substantially increased polarity over the hydrocarbon and monoacid species from which they probably derive: as late members of biodegradation processes they may be useful indicators of weathering and ageing, not only of OSPW, but potentially of crude oil residues more generally. CONCLUSIONS: Structures of O4 species in OSPW have been identified. This confirms pathways of microbial biodegradation, which were only postulated previously, and may be a further indication that remediation of OSPW toxicity can occur by natural microbial action. The presence and abundance of these diacids might therefore be useful as a measure of biodegradation and weathering

    The Normative and the Evaluative: The Buck-Passing Account of Value

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    Many have been attracted to the idea that for something to be good there just have to be reasons to favour it. This view has come to be known as the buck-passing account of value. According to this account, for pleasure to be good there need to be reasons for us to desire and pursue it. Likewise for liberty and equality to be values there have to be reasons for us to promote and preserve them. Extensive discussion has focussed on some of the problems that the buck-passing account faces, such as the 'wrong kind of reason' problem. Less attention, however, has been paid as to why we should accept the buck-passing account or what the theoretical pay-offs and other implications of accepting it are. The Normative and the Evaluative provides the first comprehensive motivation and defence of the buck-passing account of value. Richard Rowland argues that the buck-passing account explains several important features of the relationship between reasons and value, as well as the relationship between the different varieties of value, in a way that its competitors do not. He shows that alternatives to the buck-passing account are inconsistent with important views in normative ethics, uninformative, and at odds with the way in which we should see practical and epistemic normativity as related. In addition, he extends the buck-passing account to provide an account of moral properties as well as all other normative and deontic properties and concepts, such as fittingness and ought, in terms of reasons

    William Godwin and Catholicism

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    This essay traces Godwin‘s changing attitude to Catholicism by exploring a variety of texts generally considered marginal to his oeuvre and a hitherto unexamined selection of his unpublished manuscripts

    Collegiality and intellectual love

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    Utah's Economy: The Future Is Here

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    Provides a snapshot of the state's working poor families and educational and economic trends. Makes policy recommendations for education reforms to meet the needs of a knowledge-based economy, tax reforms to provide work incentives, and support services

    Being there and being then: Ideal presence and historical tourism

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    Should history be affecting? Should we engage with it emotionally? These concerns were central to eighteenth and nineteenth century historiography and remain relevant to historians, especially public historians. Eighteenth century historians like Godwin were highly exercised by the effect of history on the reader, particularly the moral effect. Relatedly, eighteenth and nineteenth historians speculated constantly on the extent to which the reader ought to be proximate to and engaged with their subject(s) and the extent to which they should be detached and maintain a distance from them. There is a tension here – some say a choice – between history as a primarily affective and aesthetic discipline and history as a cognitive, objective, scientific discipline. That history thus has a “curious doubleness” is a perennial observation, going back to Herodotus and Thucydides. But assuming the ongoing, central place of affect in History, I have to account for the general lack of affect on me of the historical place. This seems to put me at odds with most people though not, I suspect, all historians. In what follows I would like to reflect on a recent personal experience of historical tourism in Mexico. I am not an historian of Mexico: I have never formally studied Mexican history nor written about it. Yet I have been fascinated with it since being exposed to parts of William Prescott’s classic History of the Conquest of Mexico (1843) as a young boy. Nearly forty years later I managed to travel to Mexico and visit some of the places about which I had enjoyed such a profound literary-historical experience. In terms of Mexican history I was an amateur historian; above all, I was a tourist
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