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  • Journal article
    Atkin OK, Bloomfield KJ, Reich PB, Tjoelker MG, Asner GP, Bonal D, Boenisch G, Bradford MG, Cernusak LA, Cosio EG, Creek D, Crous KY, Domingues TF, Dukes JS, Egerton JJG, Evans JR, Farquhar GD, Fyllas NM, Gauthier PPG, Gloor E, Gimeno TE, Griffin KL, Guerrieri R, Heskel MA, Huntingford C, Ishida FY, Kattge J, Lambers H, Liddell MJ, Lloyd J, Lusk CH, Martin RE, Maksimov AP, Maximov TC, Malhi Y, Medlyn BE, Meir P, Mercado LM, Mirotchnick N, Ng D, Niinemets U, O'Sullivan OS, Phillips OL, Poorter L, Poot P, Prentice IC, Salinas N, Rowland LM, Ryan MG, Sitch S, Slot M, Smith NG, Turnbull MH, VanderWel MC, Valladares F, Veneklaas EJ, Weerasinghe LK, Wirth C, Wright IJ, Wythers KR, Xiang J, Xiang S, Zaragoza-Castells Jet al., 2015,

    Global variability in leaf respiration in relation to climate, plant functional types and leaf traits

    , New Phytologist, Vol: 206, Pages: 614-636, ISSN: 0028-646X

    Leaf dark respiration (Rdark) is an important yet poorly quantified component of the global carbon cycle. Given this, we analyzed a new global database of Rdark and associated leaf traits.Data for 899 species were compiled from 100 sites (from the Arctic to the tropics). Several woody and nonwoody plant functional types (PFTs) were represented. Mixed‐effects models were used to disentangle sources of variation in Rdark.Area‐based Rdark at the prevailing average daily growth temperature (T) of each site increased only twofold from the Arctic to the tropics, despite a 20°C increase in growing T (8–28°C). By contrast, Rdark at a standard T (25°C, Rdark25) was threefold higher in the Arctic than in the tropics, and twofold higher at arid than at mesic sites. Species and PFTs at cold sites exhibited higher Rdark25 at a given photosynthetic capacity (Vcmax25) or leaf nitrogen concentration ([N]) than species at warmer sites. Rdark25 values at any given Vcmax25 or [N] were higher in herbs than in woody plants.The results highlight variation in Rdark among species and across global gradients in T and aridity. In addition to their ecological significance, the results provide a framework for improving representation of Rdark in terrestrial biosphere models (TBMs) and associated land‐surface components of Earth system models (ESMs).
  • Conference paper
    Ritson JP, Clark JM, Graham NJD, Templeton MR, Freeman Cet al., 2015,

    Dissolved organic carbon (DOC) release following drought: influence of DOC source and drought severity on drinking water treatment

    , 249th American Chemical Society (ACS) National Meeting and Exposition, Denver, Colorado, USA
  • Journal article
    Hewa Dewage HARINI, wu BILLY, Tsoi ANTHONY, Yufit VLADIMIR, Offer GREGORY, Brandon NIGELet al., 2015,

    A novel regenerative hydrogen cerium fuel cell for energy storage applications

    , Journal of Materials Chemistry A, Vol: 3, Pages: 9446-9450, ISSN: 2050-7496

    A novel regenerative hydrogen cerium fuel cell is presented which has the potential to deliver both low cost and high performance. A 5 cm2 prototype is demonstrated, achieving 148 mW cm−2 when fully charged. Rate determining processes within the cell are identified.
  • Journal article
    Niu B, Al-Menhali A, Krevor SC, 2015,

    The impact of reservoir conditions on the residual trapping of carbon dioxide in Berea sandstone

    , WATER RESOURCES RESEARCH, Vol: 51, Pages: 2009-2029, ISSN: 0043-1397
  • Journal article
    Bingham RG, Rippin DM, Karlsson NB, Corr HFJ, Ferraccioli F, Jordan TA, Le Brocq AM, Rose KC, Ross N, Siegert MJet al., 2015,

    Ice-flow structure and ice dynamic changes in the Weddell Sea sector of West Antarctica from radar-imaged internal layering

    , JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE, Vol: 120, Pages: 655-670, ISSN: 2169-9003
  • Journal article
    Foster T, Brozovic N, Butler AP, 2015,

    Analysis of the impacts of well yield and groundwater depth on irrigated agriculture

    , JOURNAL OF HYDROLOGY, Vol: 523, Pages: 86-96, ISSN: 0022-1694
  • Journal article
    Jordan JR, Kimura S, Holland PR, Jenkins A, Piggott MDet al., 2015,

    On the Conditional Frazil Ice Instability in Seawater

    , JOURNAL OF PHYSICAL OCEANOGRAPHY, Vol: 45, Pages: 1121-1138, ISSN: 0022-3670
  • Journal article
    Martin-Short R, Hill J, Kramer SC, Avdis A, Allison PA, Piggott MDet al., 2015,

    .Tidal resource extraction in the Pentland Firth, UK: Potential impacts on flow regime and sediment transport in the Inner Sound of Stroma

    , RENEWABLE ENERGY, Vol: 76, Pages: 596-607, ISSN: 0960-1481
  • Journal article
    Hey J, Malloy AC, Martinez-Botas R, Lamperth Met al., 2015,

    Conjugate heat transfer analysis of an energy conversion device with an updated numerical model obtained through inverse identification

    , ENERGY CONVERSION AND MANAGEMENT, Vol: 94, Pages: 198-209, ISSN: 0196-8904
  • Journal article
    Pfeifer M, Lefebvre V, Turner E, Cusack J, Khoo M, Chey VK, Peni M, Ewers RMet al., 2015,

    Deadwood biomass: an underestimated carbon stock in degraded tropical forests?

    , ENVIRONMENTAL RESEARCH LETTERS, Vol: 10, ISSN: 1748-9326
  • Journal article
    D'Arcy M, Boluda DCR, Whittaker AC, Carpineti Aet al., 2015,

    Dating alluvial fan surfaces in Owens Valley, California, using weathering fractures in boulders

    , EARTH SURFACE PROCESSES AND LANDFORMS, Vol: 40, Pages: 487-501, ISSN: 0197-9337
  • Journal article
    Deledalle F, Kirchartz T, Vezie MS, Campoy-Quiles M, Tuladhar PS, Nelson J, Durrant JRet al., 2015,

    Understanding the Effect of Unintentional Doping on Transport Optimization and Analysis in Efficient Organic Bulk-Heterojunction Solar Cells

    , PHYSICAL REVIEW X, Vol: 5, ISSN: 2160-3308
  • Journal article
    Ruiz-Trejo E, Zhou Y, Brandon NP, 2015,

    On the manufacture of silver-BaCe0.5Zr0.3Y0.16Zn0.04O3−δ composites for hydrogen separation membranes

    , International Journal of Hydrogen Energy, Vol: 40, Pages: 4146-4153, ISSN: 1879-3487

    Silver- BaCe0.5Zr0.3Y0.16Zn0.04O3−δ (Ag/BCZYZ) composites were investigated due to their potential application as hydrogen separation membranes, with emphasis on their fabrication and characterization. A precursor powder of BCZYZ was prepared via a wet chemical route and characterized by XRD, SEM and dilatometry. The precursor powder was coated with silver using Tollens reaction and then sintered under a variety of conditions. It was possible to obtain dense samples with a low level of non-percolating silver (2 vol%). Silver was present even if sintered at 1300 °C as it remained trapped in the ceramic matrix. The overall conductivity of a dense sample with 2 vol% of silver increased when compared to pure BCZYZ, and in particular the grain boundary resistance decreased considerably. A measurement of the open circuit voltage in fuel cell mode indicates the presence of mixed electronic-protonic conductivity in the composite.
  • Journal article
    Voulvoulis N, 2015,

    The potential of water reuse as a management option for water security under the ecosystem services approach

    , DESALINATION AND WATER TREATMENT, Vol: 53, Pages: 3263-3271, ISSN: 1944-3994
  • Journal article
    Staffell I, Green R, 2015,

    Is There Still Merit in the Merit Order Stack? The Impact of Dynamic Constraints on Optimal Plant Mix

    , IEEE Transactions on Power Systems, Vol: 31, Pages: 43-53, ISSN: 1558-0679

    The merit order stack is used to tackle a wide variety of problems involving electricity dispatch. The simplification it relies on is to neglect dynamic issues such as the cost of starting stations. This leads the merit order stack to give a poor representation of the hourly pattern of prices and under-estimate the optimal level of investment in both peaking and inflexible baseload generators, and thus their run-times by up to 30%. We describe a simple method for incorporating start-up costs using a single equation derived from the load curve and station costs. The technique is demonstrated on the British electricity system in 2010 to test its performance against actual outturn, and in a 2020 scenario with increased wind capacity where it is compared to a dynamic unit-commitment scheduler. Our modification yields a better representation of electricity prices and reduces the errors in capacity investment by a factor of two.
  • Journal article
    Kondrashov D, Berloff P, 2015,

    Stochastic modeling of decadal variability in ocean gyres

    , GEOPHYSICAL RESEARCH LETTERS, Vol: 42, Pages: 1543-1553, ISSN: 0094-8276
  • Journal article
    Chiong MS, Rajoo S, Romagnoli A, Costall AW, Martinez-Botas RFet al., 2015,

    Non-adiabatic pressure loss boundary condition for modelling turbocharger turbine pulsating flow

    , Energy Conversion and Management, Vol: 93, Pages: 267-281, ISSN: 0196-8904

    This paper presents a simplified methodology of pulse flow turbine modelling, as an alternative over the meanline integrated methodology outlined in previous work, in order to make its application to engine cycle simulation codes much more straight forward. This is enabled through the development of a bespoke non-adiabatic pressure loss boundary to represent the turbine rotor. In this paper, turbocharger turbine pulse flow performance predictions are presented along with a comparison of computation duration against the previously established integrated meanline method. Plots of prediction deviation indicate that the mass flow rate and actual power predictions from both methods are highly comparable and are reasonably close to experimental data. However, the new boundary condition required significantly lower computational time and rotor geometrical inputs. In addition, the pressure wave propagation in this simplified unsteady turbine model at different pulse frequencies has also been found to be in agreement with data from the literature, thereby supporting the confidence in its ability to simulate the wave action encountered in turbine pulse flow operation.
  • Journal article
    Yokoya K, Zettler LW, Kendon JP, Bidartondo MI, Stice AL, Skarha S, Corey LL, Knight AC, Sarasan Vet al., 2015,

    Preliminary findings on identification of mycorrhizal fungi from diverse orchids in the Central Highlands of Madagascar

    , Mycorrhiza, Vol: 25, Pages: 611-625, ISSN: 1432-1890

    The Orchid flora of Madagascar is one of the most diverse with nearly 1000 orchid taxa, of which about 90 % are endemic to this biodiversity hotspot. The Itremo Massif in the Central Highlands of Madagascar with a Highland Subtropical climate range encompasses montane grassland, igneous and metamorphic rock outcrops, and gallery and tapia forests. Our study focused on identifying culturable mycorrhizae from epiphytic, lithophytic, and terrestrial orchid taxa to understand their diversity and density in a spatial matrix that is within the protected areas. We have collected both juvenile and mature roots from 41 orchid taxa for isolating their orchid mycorrhizal fungi (OMF), and to culture, identify, and store in liquid nitrogen for future studies. Twelve operational taxonomic units (OTUs), of three known orchid mycorrhizal genera, were recognized by analysis of internal transcribed spacer (ITS) sequences of 85 isolates, and, by comparing with GenBank database entries, each OTU was shown to have closely related fungi that were also found as orchid associates. Orchid and fungal diversity were greater in gallery forests and open grasslands, which is very significant for future studies and orchid conservation. As far as we know, this is the first ever report of detailed identification of mycorrhizal fungi from Madagascar. This study will help start to develop a programme for identifying fungal symbionts from this unique biodiversity hotspot, which is undergoing rapid ecosystem damage and species loss. The diversity of culturable fungal associates, their density, and distribution within the Itremo orchid hotspot areas will be discussed.
  • Journal article
    Milner-Gulland EJ, Pan Y, 2015,

    Using local ecological knowledge to assess the status of the Critically Endangered Chinese giant salamander Andrias davidianus in Guizhou Province, China

    , Oryx, ISSN: 1365-3008

    The Critically Endangered Chinese giant salamander Andrias davidianus, the world's largest amphibian, is severely threatened by unsustainable exploitation of wild individuals. However, field data with which to assess the salamander's status, population trends, or exploitation across its geographical range are limited, and recent field surveys using standard ecological field techniques have typically failed to detect wild individuals. We conducted community-based fieldwork in three national nature reserves (Fanjingshan, Leigongshan and Mayanghe) in Guizhou Province, China, to assess whether local ecological knowledge constitutes a useful tool for salamander conservation. We collected a sample of dated salamander sighting records and associated data from these reserves for comparative assessment of the relative status of salamander populations across the region. Although Fanjingshan and Leigongshan are still priority sites for salamander conservation, few recent sightings were recorded in either reserve, and respondents considered that salamanders had declined locally at both reserves. The species may already be functionally extinct at Mayanghe. Although respondent data on threats to salamanders in Guizhou are more difficult to interpret, overharvesting was the most commonly suggested explanation for salamander declines, and it is likely that the growing salamander farming industry is the primary driver of salamander extraction from Guizhou's reserves. Questionnaire-based surveys can collect novel quantitative data that provide unique insights into the local status of salamander populations, and we advocate wide-scale incorporation of this research approach into future salamander field programmes.
  • Journal article
    Stockford C, Brandon N, Irvine J, Mays T, Metcalfe I, Book D, Ekins P, Kucernak A, Molkov V, Steinberger-Wilckens R, Shah N, Dodds P, Dueso C, Samsatli S, Thompson Cet al., 2015,

    H2FC SUPERGEN: An overview of the Hydrogen and Fuel Cell research across the UK

    , International Journal of Hydrogen Energy, Vol: 40, Pages: 5534-5543, ISSN: 1879-3487

    The United Kingdom has a vast scientific base across the entire Hydrogen and Fuel Cell research landscape, with a world class academic community coupled with significant industrial activity from both UK-based Hydrogen and Fuel Cell companies and global companies with a strong presence within the country. The Hydrogen and Fuel Cell (H2FC) SUPERGEN Hub, funded by the Engineering and Physical Sciences Research Council (EPSRC), was established in 2012 as a five-year programme to bring the UK's H2FC research community together. Here we present the UK's current Hydrogen and Fuel Cell activities along with the role of the H2FC SUPERGEN Hub.
  • Journal article
    Maxwell SL, Milner-Gulland EJ, Jones JPG, Knight AT, Bunnefeld N, Nuno A, Bal P, Earle S, Watson JEM, Rhodes JRet al., 2015,

    Being smart about SMART environmental targets

    , SCIENCE, Vol: 347, Pages: 1075-1076, ISSN: 0036-8075
  • Journal article
    Bakewell C, Fateh-Iravani G, Beh D, Myers D, Tabthong S, Hormnirun P, White AJ, Long N, Williams CKet al., 2015,

    Comparing a series of 8-quinolinolato complexes of aluminium, titanium and zinc as initiators for the ring-opening polymerization of rac-lactide.

    , Dalton Transactions, Vol: 44, ISSN: 1477-9226

    The preparation and characterization of a series of 8-hydroxyquinoline ligands and their complexes with Ti(iv), Al(iii) and Zn(ii) centres is presented. The complexes are characterized using NMR spectroscopy, elemental analysis and, in some cases, by single crystal X-ray diffraction experiments. The complexes are compared as initiators for the ring-opening polymerization of racemic-lactide; all the complexes show moderate/good rates and high levels of polymerization control. In the case of the titanium or aluminium complexes, moderate iso-selectivity is observed (Pi = 0.75), whereas in the case of the zinc complexes, moderate hetero-selectivity is observed (Ps = 0.70).
  • Journal article
    Mac Dowell N, Shah N, 2015,

    The multi-period optimisation of an amine-based CO<sub>2</sub> capture process integrated with a super-critical coal-fired power station for flexible operation

    , COMPUTERS & CHEMICAL ENGINEERING, Vol: 74, Pages: 169-183, ISSN: 0098-1354
  • Journal article
    Ren Z, Graham N, 2015,

    Treatment of Humic Acid in Drinking Water by Combining Potassium Manganate (Mn(VI)), Ferrous Sulfate, and Magnetic Ion Exchange

    , ENVIRONMENTAL ENGINEERING SCIENCE, Vol: 32, Pages: 175-178, ISSN: 1092-8758
  • Journal article
    Dimitrov SD, Wheeler S, Niedzialek D, Schroeder BC, Utzat H, Frost JM, Yao J, Gillett A, Tuladhar PS, McCulloch I, Nelson J, Durrant JRet al., 2015,

    Polaron pair mediated triplet generation in polymer/fullerene blends

    , Nature Communications, Vol: 6, ISSN: 2041-1723

    Electron spin is a key consideration for the function of organic semiconductors in light-emitting diodes and solar cells, as well as spintronic applications relying on organic magnetoresistance. A mechanism for triplet excited state generation in such systems is by recombination of electron-hole pairs. However, the exact charge recombination mechanism, whether geminate or nongeminate and whether it involves spin-state mixing is not well understood. In this work, the dynamics of free charge separation competing with recombination to polymer triplet states is studied in two closely related polymer-fullerene blends with differing polymer fluorination and photovoltaic performance. Using time-resolved laser spectroscopic techniques and quantum chemical calculations, we show that lower charge separation in the fluorinated system is associated with the formation of bound electron-hole pairs, which undergo spin-state mixing on the nanosecond timescale and subsequent geminate recombination to triplet excitons. We find that these bound electron-hole pairs can be dissociated by electric fields.
  • Journal article
    Madani K, Khatami S, 2015,

    Water for Energy: Inconsistent Assessment Standards and Inability to Judge Properly

    , Current Sustainable/Renewable Energy Reports, Vol: 2, Pages: 10-16

    The water-energy nexus field is experiencing growing attention to assessing the impacts of energy generation on water resources. Numerous studies in recent years have used a range of metrics and methods for measuring and quantifying the water impacts of energy. This article argues that the field is suffering from a lack of consistency in the interpretation and application of different evaluation metrics due to competition for the development of the ‘correct’ evaluation method. The uncertainties caused by inconsistent analysis methods, assumptions, scales and boundaries make the available information confusing and hamper our abilities to understand comprehensively and judge properly. The article highlights some of the major caveats that need to be considered in using the results of the previous studies and applying the existing metrics for evaluating the impacts of energy production on water resources.
  • Journal article
    Berloff P, 2015,

    Dynamically consistent parameterization of mesoscale eddies. Part I: Simple model

    , Ocean Modelling, Vol: 87, Pages: 1-19, ISSN: 1463-5003

    This work aims at developing a framework for dynamically consistent parameterization of mesoscale eddy effects for use in non-eddy-resolving ocean circulation models. The proposed eddy parameterization framework is successfully tested on the classical, wind-driven double-gyre model, which is solved both with explicitly resolved vigorous eddy field and in the non-eddy-resolving configuration with the eddy parameterization replacing the eddy effects. The parameterization locally approximates transient eddy flux divergence by spatially localized and temporally periodic forcing, referred to as the plunger, and focuses on the linear-dynamics flow solution induced by it. The nonlinear self-interaction of this solution, referred to as the footprint, characterizes and quantifies the induced cumulative eddy forcing exerted on the large-scale flow. We find that spatial pattern and amplitude of the footprint strongly depend on the underlying large-scale and the corresponding relationships provide the basis for the eddy parameterization and its closure on the large-scale flow properties. Dependencies of the footprints on other important parameters of the problem are also systematically analyzed. The parameterization utilizes the local large-scale flow information, constructs and scales the corresponding footprints, and then sums them up over the gyres to produce the resulting eddy forcing field, which is interactively added to the model as an extra forcing. The parameterization framework is implemented in the simplest way, but it provides a systematic strategy for improving the implementation algorithm.
  • Journal article
    Belcher CM, Hadden RM, Rein G, Morgan JV, Artemieva N, Goldin Tet al., 2015,

    An experimental assessment of the ignition of forest fuels by the thermal pulse generated by the Cretaceous-Palaeogene impact at Chicxulub

    , JOURNAL OF THE GEOLOGICAL SOCIETY, Vol: 172, Pages: 175-185, ISSN: 0016-7649
  • Journal article
    Field KJ, Leake JR, Tille S, Allinson KE, Rimington WR, Bidartondo MI, Beerling DJ, Cameron DDet al., 2015,

    From mycoheterotrophy to mutualism: mycorrhizal specificity and functioning in <i>Ophioglossum vulgatum</i> sporophytes

    , NEW PHYTOLOGIST, Vol: 205, Pages: 1492-1502, ISSN: 0028-646X
  • Journal article
    Lomax G, Workman M, Lenton T, Shah Net al., 2015,

    Reframing the policy approach to greenhouse gas removal technologies

    , ENERGY POLICY, Vol: 78, Pages: 125-136, ISSN: 0301-4215

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