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Embracing social procurement: an institutional work perspective on implementation in procurement practices
No full textOrganisations are increasingly using their purchasing power to create social value, a
practice known as social procurement. This involves adapting existing procurement
practices to incorporate social norms and practices. However, this process can lead to
tensions and conflicts, requiring organisations to balance the priorities of different
procurement practices. This study uses an institutional work lens to examine how
organisations change and alter existing practices to navigate the complexity of integrating
social procurement and traditional procurement practices. An analysis of six case studies
reveals that organisations use various strategies of institutional work, which are
influenced by contextual factors
EEG signal processing techniques and applications—2nd Edition
Get PDFElectroencephalography (EEG), as a well-established, non-invasive tool, has been successfully applied to a wide range of conditions due to its many evident advantages, such as economy, portability, easy operation, easy accessibility, and widespread availability in hospitals. EEG signals, with ultra-high time resolution, are vital in understanding brain functions. Traditionally, considerable attention in EEG signal processing and analysis has been paid to understanding brain activities from various perspectives, such as the detection and identification of abnormal frequencies in specific biological states, spatial–temporal and morphological characteristics of neurological disorder behaviours (e.g., paroxysmal or persistent discharges), the response of the brain nervous/neurological system to external stimuli, and the effects and responses to intermittent photic stimulation [1].Sensor
Effect of growing temperature on root carbohydrate content and postharvest asparagus tip breakdown
Get PDFBACKGROUND
Tip breakdown has been identified as the main issue causing deterioration in asparagus quality during storage; however, the underlying mechanisms responsible for its development are unknown. Previous work showed higher incidence of tip breakdown occurring later in the season, when growing temperature was higher. Spears from two growing conditions (cooler vs warmer) were harvested throughout the season to assess tip breakdown incidence and quality attributes (asparagine and non‐structural carbohydrates) during storage, with the aim of enhancing understanding and identifying potential biomarkers of this physiological disorder. Root samples were also collected just after harvest to determine if storage root carbohydrate content was associated with a predisposition to tip breakdown.
RESULTS
Rapid growth due to warmer temperatures (up to 45 °C) resulted in spears with lower sugar content and higher incidence of tip breakdown in comparison with cooler conditions. Asparagine slowly increased through the season (7 to 11 mg g−1 DW) with no differences between growing conditions, suggesting that it is not a biomarker for tip breakdown. Pre‐season spears (warm temperature only) had double the amount of sugar in comparison with early season spears, with no incidence of tip breakdown despite an extended storage period (up to 18 days at 7 °C). Sugar concentration in roots was similar between growing conditions and between pre‐ and early season despite clear differences in spear sugar content.
CONCLUSION
These results showed a strong positive link between cooler growing conditions, high spear sugar content, and low susceptibility to tip breakdown, which was not reflected in root sugar concentrations. However, further research is needed to understand the molecular mechanisms responsible for tip breakdown.This work was supported by Innovate UK (Project number: 102315), the Biotechnology and Biological Sciences Research Council (BBSRC: BB/N004906/1) and Cobrey Farms.Journal of the Science of Food and Agricultur
Calcium looping for pulp and paper industry decarbonisation and hydrogen production from biomass and waste
Get PDFManovic, Vasilije - Associate SupervisorGlobal CO₂ emissions from fossil fuels have been rising for more than a century.
Nevertheless, to meet the ambitious targets set by the Paris Agreement,
greenhouse gas emissions must be substantially reduced. The improvement of
energy efficiency, implementation of carbon capture and reduction of fossil fuel
dependency can play an important role. Of the CO₂ capture technologies, amine
scrubbing is the most mature technology; however, calcium looping has shown
to be a promising one. Thus, this research aimed to assess the techno-economic
feasibility of calcium lopping as a carbon capture technology for combined heat,
power and hydrogen production from biomass and/or waste. First, a new concept
for the conversion of the pulp and paper industry to carbon-negative that relies
on the inherent CO₂ capture capability of the Kraft process was proposed. This
concept has shown that a pulp and paper plant can turn from importer to
electricity exporter with the cost of CO₂ avoided of 39.0 €/tсо₂ . Second, in the
pulp and paper industry, two carbon capture and storage routes were compared,
calcium looping retrofitted to the pulp and paper plant and calcium looping
coupled with black liquor gasification. The latter was assessed for H₂ production
and for electricity generation with a gas turbine combined cycle or solid-oxide fuel
cell. The last alternative has shown that the pulp and paper plant can also
become a net electricity export asset at the expense of the cost of CO₂ avoided,
50.8 €/tсо₂ . On the contrary, the alternative for H₂ production presented the
highest energy penalty but the lowest cost of CO₂ avoided (48.8 €/tсо₂ ). Third,
the feasibility of calcium looping for H₂ production and in-situ CO₂ capture was
assessed for waste-to-energy conversion in a greenfield scenario. However, this
resulted in a significantly higher levelised cost of hydrogen (5.0 €/kgн₂ ) compared
to that estimated for conventional gasification (2.7 €/kgн₂ ). Although calcium
looping is more cost-efficient for carbon capture in a retrofitted scenario, this
technology can become a competitive technology for hydrogen production in a
greenfield scenario.PhD in Energy and Powe
Molecular mechanistic insights towards aggregation of nano-biochar moderated by aromatic components in dissolved organic matter
Get PDFNano-biochar (NBC) is a promising tool for sustainable remediation of contaminants in aquatic environments. However, the presence of ubiquitous ions and dissolved organic matter (DOM) can impact NBC aggregation, resulting in reduced application efficacy and potential ecological risks. Understanding and regulating NBC aggregation offers valuable insights for its deployment. This study integrated batch aggregation experiments, theoretical models, Fourier transform ion cyclotron resonance-mass spectrometry (FTICR-MS), and density functional theory (DFT) calculations to explore the behaviors and mechanisms of NBC aggregation with coexisting ions and model DOM. NBC aggregation kinetics followed the classical Derjaguin-Landau-Verwey-Overbeek (DLVO) theory in both NBC-ions and NBC-ions-fulvic acid (FA) solutions, indicating that the aggregation process is controlled by Van der Waals forces and electrostatic repulsion. Mono/di-valent electrolytes promoted NBC aggregation, whereas FA moderated it, with higher molecular weight FA fractions exhibiting superior performance. Three-dimensional excitation-emission (3D-EEM) fluorescence spectra and Parallel factor analysis (PARAFAC) analyses revealed that HA-like substances, followed by FA-like substances, can form a complex with ions, thereby moderating NBC aggregation. FTICR-MS scans identified lignin substances with aromatic structures as key components that effectively reduce the promoted NBC aggregation with coexisting mono/di-valent electrolytes. DFT calculations confirmed that the aromatic structures in FA spontaneously form complexes with electrolytes, thereby potentially regulating NBC aggregation. This research highlights potential strategies for regulating NBC applications and offers insights into the behavior of nanoparticles in aquatic environments.National Natural Science Foundation of ChinaThis research was supported by the National Natural Science Foundation of China (42130711, 42277399, 42307499, and 42467031), Yunnan Major Scientific and Technological Projects (202202AG050019).Environment Internationa
Supplementation strategies to control propionic acid accumulation resulting from ammonia inhibition in dry anaerobic digestion: osmoprotectants, activated carbon and trace elements
Get PDFPropionic acid accumulation in anaerobic digestion is a common sign of inhibition at high ammonia levels. To mitigate accumulation three supplementations were tested: osmoprotectants, trace elements and activated carbon. Activated carbon and osmoprotectants (MgCl2) achieved a 28 % increase in methane yield and a 3-fold reduction in hydrogen partial pressure compared with the control. Trace elements supplementation increased methane formation by 18 % without preventing instability. No supplementation avoided propionic accumulation, although MgCl2 delayed it. Activated carbon and MgCl2 supported proliferation of strict hydrogenotrophs, increasing microbial redundance with expected positive impacts on process resilience. Evidence beyond previous studies on the role of retention time as a control parameter of versatile archaea's methanogenic pathway is also provided. As retention time is reduced, syntrophic acetate oxidising bacteria are washed out of the system, likely resulting from an increase in their doubling time with inhibitors accumulation, preventing hydrogenotrophic methanogenesis and supporting previous observations of Methanosarcina being forced to conduct acetoclastic methanogenesis. Longer retention times to accommodate longer doubling times or alleviation of inhibition with activated carbon and MgCl2 supported retention of syntrophic acetate oxidising bacteria, enabling strict hydrogenotrophic archaea to proliferate. These supplementations would allow operation of industrial scale ADs at shorter retention times and higher throughputs. Results suggest that osmoprotectants and activated carbon addition were linked to a reduction in archaea's osmotic pressure and enhanced direct interspecies transfer, respectively, leading to increased methane formation despite propionic levels.Engineering and Physical Sciences Research CouncilThis work was undertaken during I. Rocamora’s Engineering Doctorate research at Cranfield University, funded jointly by the Engineering & Physical Sciences Research Council (EPSRC) Skills Technology Research and Management (STREAM) EngD Programme (Grant EP/ L015412/1) and Thalia Waste Management.Journal of Environmental Chemical Engineerin
CFD modelling and simulation on a lambda wing at subsonic speed
Get PDFThis paper presents and discusses the results of a study at subsonic airspeed of the aerodynamic characteristics of the Swept Wing Flow Test (SWIFT) lambda wing configuration, which was undertaken as part of the NATO AVT-298 Task Group activity on “Reynolds Number Scaling Effects on Swept Wing Flows”. While the task group studied the aerodynamics of this unconventional wing shape across the subsonic and transonic Mach number, and a wide range of Reynolds numbers via cryogenic testing in the NASA NTF wind tunnel, this paper focuses only on the Mach 0.2 conditions at a Reynolds number, based on mean chord, of 2.5 million, for which the model was tested at the ARA Transonic Wind Tunnel in the UK. Various fidelity CFD methods were employed for comparison with experimental data, over a pitch sweep from -4 to 20 degrees angle of attack, including the Viscous Full Potential (VFP) method, RANS, Unsteady RANS and Delayed Detached Eddy Simulation (DDES). The results for this case, highlight the complex 3D stall, initiating inboard, associated with this class of swept wing, which is very different from that seen on conventional swept, tapered wings typically seen on civil transport aircraft, which tends to initiate towards the tip. While the results show that, of the RANS turbulence models tested, the k-omega SST turbulence model most effectively predicted the experimental data, but none of the linear eddy viscosity models could resolve the benign stall characteristics captured in the experiment. Only the DDES method was found to effectively predict the post stall characteristics to some degree of accuracy. The VFP method generated results in a fraction of the time (seconds compared with hours), required for higher fidelity CFD solution, and was found to provide data with equivalent accuracy to RANS based methods for pre-stall conditions.The authors acknowledge the NATO AVT organization for sponsoring the activity on which this study is a small part, to the UK DSTL and the US Air Force for funding support for the experiments and ARA and NASA for their support with experimental data and computational analysis.AIAA SCITECH 2025 Foru
Feasibility study on using combined tomography and spectroscopy techniques to evaluate the physical and chemical characteristics of organo-mineral fertilisers
Get PDFFertilisers play a key role in agriculture, providing key nutrients needed by crops to ensure a secure food supply. However, with increasing prices and rising environmental concerns, there is a growing need to rely on alternative and sustainable fertiliser sources, introducing the opportunity to use organic amendments to formulate organo-mineral fertilisers (OMF). Despite their environmental advantages, the inherent variability in composition of organic amendments within OMF poses a challenge for their standardization. This study aims to use OMF derived from anaerobic digestate and coupled with carbon capture technologies to analyze for its physical characteristics and chemical composition using neutron computed tomography (NCT), X-ray computed tomography (XCT) and Raman spectroscopy (RS). This is a feasibility study to assess using non-destructive techniques on OMF as previously this has not been explored. This work represents the first attempt to utilize a combination of imaging techniques to investigate on OMF and demonstrates their feasibility for measuring the variability between individual samples. This is a proof-of-concept study which shows that combining NCT and XCT can provide images on how uniformly packed each OMF pellet are. The use of RS is to characterize OMF is more challenging largely due to the high fluorescence background arising from its matrix. This study needs to be further developed to enable image-based analysis using machine learning algorithms to determine characteristics of large batches of OMF. Further development is needed building on this work to quantify OMF pellet characteristics so that it can be confidently used as novel fertilisers in agriculture.The authors would like to acknowledge funding received from the STFC Food Network + which supported this work and encouraged collaboration with scientists at STFC Rutherford Appleton Laboratory and Diamond Light Source.Frontiers in Sustainable Food System
Energy comparison in terminal area for narrow body, SAF and LH2 aircraft
Get PDFThe aviation industry is transitioning towards sustainable propulsion technologies to address stringent environmental targets and rising operational demands. This study evaluates actuator energy requirements in terminal phase for three narrow-body aircraft architectures: a conventional A320-like platform, a more-electric aircraft powered by Sustainable Aviation Fuel (SAF), and a Liquid Hydrogen (LH2) concept. Detailed actuator models for electro-mechanical and servo-hydraulic systems were developed and integrated into mission-level simulations to capture power and energy profiles across key subsystems, including high-lift devices, landing gear, spoilers, brakes, and steering. Results show that while the baseline aircraft consumes the most energy due to hydraulic inefficiencies, the SAF and LH2 configurations demonstrate notable reductions in actuator energy demands. The findings highlight how system-level electrification and architectural innovations can enhance terminal efficiency, paving the way for greener, high-performance single-aisle aircraft.This research was funded by Innovate UK grant number 10002411, under the ATI/IUK Project: LANDOne, with Airbus UK as Industrial LeadAIAA Aviation Forum and Ascend 202
Use of bioaerosol stakeholder mapping and engagement for the development of future strategic collaborations: a UK perspective
Get PDFThis article is part of the Aerosols and Microbiology: Connecting Disciplines in the Post-Pandemic Era collection.Stakeholder mapping is a process that involves identifying, characterizing and visualizing the connections between stakeholders. It is important to understand the main influencers and those with an interest in or affected by a certain project or field. Stakeholders can have diverse perspectives and priorities, some complementary and others conflicting, and it is important to develop effective engagement strategies to facilitate progress with the desired impact. Here, we present the first such analysis for the bioaerosol research field. This study presents data from a survey and outcomes from workshops attended by researchers with an interest in bioaerosols. Bioaerosols are airborne particles from biological origin that can have diverse and serious effects on public health. Stakeholders were identified and analysed in terms of sector, engagement type, interest and influence scores, expertise and the nature of the relationships between them. Limitations of this study are discussed with suggestions for improvements. The workshops included discussions on missing stakeholders, skills and knowledge gaps, the uses of stakeholder mapping and how to facilitate skill sharing, collaboration and effective progress in the future. We share this to provide a simple but successful approach for researchers with no previous practical experience in stakeholder mapping to modify, use and realize similar benefits within their own fields.The indoor/outdoor bioaerosol interface and relationship network (BioAirNet), funded by UK Research and Innovation grant (NE/V002171/1).The National Institute for Health and Care Research (NIHR) Health Protection Research Unit (HPRU) in Environmental Change and Health (NIHR 200909).A partnership between the UK Health Security Agency (UKHSA) and the London School of Hygiene and Tropical Medicine, University College London and the Met Office.The NIHR HPRU in Environmental Exposures and Health (NIHR 200880).The NIHR HPRU in Chemical and Radiation Threats and Hazards (NIHR 200922).A partnership between UKHSA, Imperial College London, the University of Cambridge and King’s College London.The NIHR HPRU in Environmental Exposures and Health developmental award (NIHR 200901).A partnership between UKHSA, the University of Leicester and the Health and Safety Executive (HSE).Microbiolog