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Review of bioinspired composites for thermal energy storage: preparation, microstructures and properties
Get PDFBioinspired composites for thermal energy storage have gained much attention all over the world. Bioinspired structures have several advantages as the skeleton for preparing thermal energy storage materials, including preventing leakage and improving thermal conductivity. Phase change materials (PCMs) play an important role in the development of energy storage materials because of their stable chemical/thermal properties and high latent heat storage capacity. However, their applications have been compromised, owing to low thermal conductivity and leakage. The plant-derived scaffolds (i.e., wood-derived SiC/Carbon) in the composites can not only provide higher thermal conductivity but also prevent leakage. In this paper, we review recent progress in the preparation, microstructures, properties and applications of bioinspired composites for thermal energy storage. Two methods are generally used for producing bioinspired composites, including the direct introduction of biomass-derived templates and the imitation of biological structures templates. Some of the key technologies for introducing PCMs into templates involves melting, vacuum impregnation, physical mixing, etc. Continuous and orderly channels inside the skeleton can improve the overall thermal conductivity, and the thermal conductivity of composites with biomass-derived, porous, silicon carbide skeleton can reach as high as 116 W/m*K. In addition, the tightly aligned microporous structure can cover the PCM well, resulting in good leakage resistance after up to 2500 hot and cold cycles. Currently, bioinspired composites for thermal energy storage hold the greatest promise for large-scale applications in the fields of building energy conservation and solar energy conversion/storage. This review provides guidance on the preparation methods, performance improvements and applications for the future research strategies of bioinspired composites for thermal energy storage.National Natural Science Foundation of ChinaThis research was funded by the National Natural Science Foundation of China (No. 52002174 and 52372111), Natural Science Foundation of Jiangsu Province (No. BK20200455), State Key Laboratory of Powder Metallurgy, Central South University, Changsha, China and Innovation Project of Nanjing University of Aeronautics and Astronautics (xcxjh20220617 and 2023CX006060).Journal of Composites Scienc
SmartSocks: a new data collection paradigm for dementia and other neurological disorders
Get PDFBackground
Distress and agitation are predictors of entry into long‐term care and health inequalities (Schulz et al., 2004, Weir et al., 2022). Physiological data has been shown to reliably predict distress (Goodwin et al., 2019), yet wearable devices have low acceptance rates (Koumpouros & Kafazis, 2019). The current study discusses findings from a multifaceted approach investigating the detection of early signs of distress via physiological sensors in a foot‐worn device.
Method
Firstly, the acceptance and concern ratings for a foot‐worn device, SmartSocks, wrist‐worn devices, Empatica E4 and Shimmer GSR+, and chest‐worn device, Equivital within a healthy population (N = 10) were assessed with a self‐report questionnaire. Secondly, data accuracy between Shimmer ECG and Polar OH1+ was compared within a healthy population (N = 12) in a standing, sitting and supine position. Finally, an ongoing ecologically valid feasibility trial (N = 2) involving participants with dementia or a learning disability is assessing the reliability of physiological data and AI‐detected stress from SmartSocks relative to subjective ratings of distress, the Abbey Pain Scale (APS), and the Neuropsychiatric Inventory (NPI).
Result
Firstly, the SmartSocks received lowest concern ratings compared to wrist‐ and chest‐worn devices (1.64 vs <1.71). Secondly, the accuracy of SmartSocks pulse rate (PR) estimates obtained using photoplethysmography (PPG) in combination with the delineator algorithm was determined by comparing estimates to a Shimmer 1‐lead ECG, recording Mean Absolute Error (MAE)<5bpm at 64HZ for participants in a supine position (Fig. 1). This led to the development of new features for classifying PPG signal quality using neural networks, achieving approximately 95% accuracy. Finally, the initial stage of the feasibility trial indicated APS and NPI scores were lower after the participant with dementia wore SmartSocks for two weeks. Physiological data collected from the participant with a learning disability using SmartSocks showed moderate correlation (χ2 = 0.45) between the reported and AI‐detected stress over the day (Fig. 2 & 3).
Conclusion
Early findings suggest SmartSocks are more comfortable than comparable wrist‐ and chest‐worn devices, and validity of the data is comparable to other devices. Preliminary data obtained from people with dementia and learning disabilities suggest SmartSocks are capable of detecting distress to alleviate user discomfort.Alzheimer's & Dementi
Exploiting the potential of spherical PAM antenna for enhanced CRISPR-Cas12a: a paradigm shift toward a universal amplification-free nucleic acid test platform
Get PDFThe CRISPR-Cas12a system has shown tremendous potential for developing efficient biosensors. Albeit important, current CRISPR-Cas system-based diagnostic technologies (CRISPR-DX) highly rely on an additional preamplification procedure to obtain high sensitivity, inevitably leading to issues such as complicated assay workflow, cross-contamination, etc. Herein, a spherical protospacer-adjacent motif (PAM)-antenna-enhanced CRISPR-Cas12a system is fabricated for universal amplification-free nucleic acid detection with a detection limit of subfemtomolar. Meanwhile, the clinical detection capability of this sensor was further verified using gold-standard real-time quantitative polymerase chain reaction through Mycobacterium tuberculosis measurement, which demonstrated its good reliability for practical applications. Importantly, its excellent sensitivity is mainly ascribed to high efficiency of target search induced by a localized PAM-enriched microenvironment and improved catalytic activity of Cas12a (up to 4 folds). Our strategy provides some new insights for rapid and sensitive detection of nucleic acids in an amplification-free fashion.This work was supported by the National Natural Science Foundation of China (grant nos. 22176075 and 22476072) and the Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment.Leverhulme Trust, National Natural Science Foundation of China.UKRI NERC Fellowship grant (NE/R013349/2).Analytical Chemistr
Data for feasibility study on using combined tomography and spectroscopy techniques to evaluate the physical and chemical characteristics of organo-mineral fertilisers
No full textThe dataset comprises spectra for Raman Spectroscopy and reconstructed images for X-Ray Computed Tomography and neutron computed tomography.
**Please note, more data will be added here soon.**Fertilisers 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 standardisation. This study aims to use OMF derived from anaerobic digestate and coupled with carbon capture technologies to analyse for its physical characteristics and chemical composition using neutron computed tomography (NCT), X-ray computed tomography (XCT) and Raman spectroscopy (RS). This work represents the first attempt to utilise 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 characterise 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.Science and Technology Facilities Council (STFC
Wind tunnel installation effects on a high-speed exhaust flow under large blockage
Get PDFThis study presents a numerical investigation of wind tunnel installation effects on the exhaust flow for a high-speed system under a blockage ratio of 16.5%. The configuration features a nozzle and a cavity embedded at the base of an ogive-cylindrical body and is representative of future, high-speed exhausts. The work is motivated by the need of testing large, powered-on models and the size of most closed transonic tunnels available in academic research facilities. This combination leads to high blockage ratios and therefore severe flow distortion. The objective is to examine the installation effects and quantify the base flow similarity relative to unbounded conditions. The numerical approach is validated against experimental data. A jet vectoring effect is identified due to the pylon, which is intensified under choked tunnel operation. Additionally, a methodology is proposed, which allows base pressure to be compared to unbounded flow conditions. Results show that the pressure distribution agrees within 1.5% and 0.1% for the base and cavity walls, respectively. This demonstrates that local aerodynamic similarity can be established between large-blockage, tunnel-tested conditions and unbounded flow through the proposed approach. This enables the use of small-scale facilities for base flow studies of high-speed exhausts under large blockage.The authors would like to express their gratitude to Reaction Engines Ltd., Rolls-Royce Plc, and the Cranfield Air and Space Propulsion Institute (CASPI) for funding this project and granting permission to publish this research.Journal of Spacecraft and Rocket
Effective thermal diffusivity measurement using through-transmission pulsed thermography: extending the current practice by incorporating multi-parameter optimisation
Get PDFThrough-transmission pulsed thermography (PT) is an effective non-destructive testing (NDT) technique for assessing material thermal diffusivity. However, the current literature indicates that the technique has lagged behind the reflection mode in terms of technique development despite it offering better defect resolution and the detection of deeper subsurface defects. Existing thermal diffusivity measurement systems require costly setups, including temperature-controlled chambers, multiple calibrations, and strict sample size requirements. This study presents a simple and repeatable methodology for determining thermal diffusivity in a laboratory setting using the through-transmission approach by incorporating both finite element analysis (FEA) and laboratory experiments. A full-factorial design of experiments (DOE) was implemented to determine the optimum flash energy and sample thickness for a reliable estimation of thermal diffusivity. The thermal diffusivity is estimated using the already established Parker’s half-rise equation and the recently developed new least squares fitting (NLSF) algorithm. The latter not only estimates thermal diffusivity but also provides estimates for the input flash energy, reflection coefficient, and the time delay in data capture following the flash event. The results show that the NLSF is less susceptible to noise and offers more repeatable values for thermal diffusivity measurements compared to Parker, thereby establishing it as a more efficient and reliable technique.This research was performed with the help of the EPSRC platform grant (grant number EP/P027121/1). The authors of this paper would also like to thank the Cranfield Industrial Partnership Ph.D. Scholarships Scheme (CIPPS), Cranfield University, and Sun resources for co-funding this research.Sensor
Redefining the documentation of outdoor surface scatter scenes using geographic information systems
Get PDFThe field of forensic archaeology has been primarily associated with the search, location, and excavation of clandestine graves, and thus, other deposition types have been commonly neglected in research. Current literature typically addresses the use of traditional methods implemented for the excavation and recovery of human remains from clandestine graves but fails to provide the same for surface scatter scenes. This study aimed to explore the documentation of such scenes through the integration of traditional archaeological techniques, geophysical surveying techniques, and GIS. A mixed method study was created and utilized in three different simulated scatter scenes, allowing the qualitative and quantitative scope of GIS to be examined and assessed. The techniques were utilized successively and iterated until all simulated scenes had been documented. Within this study, terrain was the independent variable—this was nonrandomized and chosen to best suit sites where scatter scenes are most prevalent. Results demonstrated GIS to be an effective method in the documentation of contextual data at a forensic surface scatter scene, providing both qualitative and quantitative data. Such findings aid in understanding the admissibility of each technique in court and its impact on a case when presented as evidence. This research revealed that further exploration of surveying techniques in sites other than clandestine graves is necessary for forensic archaeology practice.Journal of Forensic Science
Spatial representation of faecal pollution in unsewered urban catchments
Get PDFWaine, Toby - Associate SupervisorIn many secondary cities in Bangladesh and other economically developing
regions in Asia, Africa and Latin America, urban sanitation is dependent on
individually constructed and maintained decentralised sanitation technologies,
e.g., septic tanks operating in the absence of a city-wide support system. In such
urban areas, wastewater is transported through a network of storm drains which
were not designed for this purpose. The release of wastewater runs the risk of
imperfect containment and high risk of exposure to faecal pathogens. Effective
methods to identify the sources and movement pathways of faecal matter within
cities are currently lacking. Here, a Sanitation Infrastructure and Faecal Flow
(SanIFFlow) approach is introduced, representing a novel methodology that
utilises open-source data to map the sanitation infrastructure and the faecal
matter sources and movement pathways. This approach is first demonstrated
through a prototype sub-catchment model within Rajshahi city, Northwest
Bangladesh. The sub-catchment model identifies and characterises the sources,
pathways, and movement of faecal matter. To refine and validate the method, an
uncertainty analysis was conducted, supplemented by a field study, to assess the
reliability of the approach. Sensitivity analysis identified five key factors
influencing the spatial pattern of faecal flow: septic tank emptying, soak pit use,
sludge removal from drains, variations in faecal matter production, and the
absence of toilets in some buildings. While each factor might have a negligible
impact individually, in combination the factors showed almost 50% faecal matter
cannot reach the outlet point. Further insights from the uncertainty analysis and
fieldwork suggest that, although the sub-catchment model has potential for
individual building level sanitation management, the existing ward-level
management system, being the smallest administrative unit in the case study city,
calls for a model at that spatial scale as a more practical approach. Building upon
this, the SanIFFlow approach has been deployed to develop a city-scale model
built from ward-level subunits, tailored for practical application in unsewered cities
like Rajshahi. This approach holds promise for global applicability, given the
widespread availability of open-source data.PhD in Water and Waste Infrastructure and Services Engineered for Resilienc
Developing a supportive organisational culture for continuous improvement in manufacturing firms in Saudi Arabia
Get PDFContinuous improvement (CI) is vital for Saudi manufacturing firms to remain competitive in the global market. However, cultural factors significantly influence CI adoption. This qualitative study, involving 28 interviews and focus groups with employees from five local manufacturing firms, explored these factors. Seven key cultural themes emerged, including communication, employee wellbeing, talent management, ethics, top management support, organisational learning, and compliance. A conceptual framework was developed to assess a firm’s cultural proximity to an ideal CI state. This framework integrates a diagnostic tool to guide firms in evaluating their cultural landscape and implementing targeted interventions for successful CI adoption. Future research should explore the long-term impacts of cultural shifts on performance and competitiveness.This research is part of Adel Algethami’s PhD dissertation funded by Saudi Government.Administrative Science
Modelling and optimising a multi-depot vehicle routing problem for freight distribution in a retail logistics network
Get PDFAn efficient freight distribution network is critical for enhancing competitiveness by lowering transportation costs and increasing profitability. This study adopts a case-based modelling approach to tackle a real-world Multi-Depot Vehicle Routing Problem (MDVRP) faced by a UK-based retailer aiming to expand its operations in northern UK. Due to high fixed costs and a limited branch network, the retailer seeks to improve operational efficiency by reducing transportation costs without establishing additional facilities. A novel mixed-integer programming model is developed to optimise the existing distribution network by incorporating realistic operational constraints. The model addresses key complexities such as driver costs, inter-depot routing, transportation hubs, multiple depots, dynamic demand, a heterogeneous fleet, cross-docking, multiple product types, vehicle capacity and travel time restrictions. Using an exact solution method, the model yields optimal results demonstrating significant reductions in transportation costs while maintaining service constraints. The findings provide valuable research insights and practical recommendations for optimising freight distribution networks under realistic and resource-constrained conditions.Computers & Industrial Engineerin