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  • ItemOpen Access
    Novel ecosystems: the new normal?
    (British Ecological Society, 2024-09-11) Harris, Jim; Bullock, James; Pettorelli, Nathalie; Perring, Michael; Mercer, Theresa
    As humans continue to radically alter the environment, new species assemblages are emerging – combinations of organisms that have never been observed before. What does this changing world mean for ecology?
  • ItemOpen Access
    3D computational fluid dynamics analysis of natural gas separation efficiency in multiphase pumping wells with heterogeneous flow regime
    (Taylor and Francis, 2024-12-31) Okafor, Charles C; Verdin, Patrick G
    This research uses 3D Computational Fluid Dynamics (CFD) simulations to investigate the downhole Natural Gas Separation Efficiency (NGSE) for multiphase pumping wells in the heterogeneous churn flow regime. Results explain the effects of key parameters such as liquid viscosity, intake port sizes/diameter, and casing diameter, on the NGSE. Methods are thus suggested to enhance the NGSE in oil field operations, and key improvements to the widely used mathematical formulations for viscous service are proposed. Transient numerical simulations were performed for a section of an experimental flow loop extracted from the literature, and the flow solution was obtained with the Volume of Fluid (VOF) model. For most simulations, turbulence effects were modelled with the k−ϵ turbulence model. The k−ω SST turbulence model was however considered for the sensitivity analysis on liquid viscosity. The final numerical results validated against the corresponding experimental data showed an average error of less than 6%. Combining past literature and current results confirms that (i), the NGSE is affected by the downhole geometry (i.e annulus space and pump intake port flow area geometry) and (ii), current analytical NGSE models are not ideal for multiphase viscous service (high viscosity Newtonian flow) in the heterogeneous flow regime. The widely used steady-state formulations might thus not be adequate for this flow regime.
  • ItemOpen Access
    Effect of biochar addition on biogas production using konjac waste through mesophilic two-phase anaerobic digestion
    (Springer Science and Business Media LLC, 2024-08-29) Sugiarto, Yusron; Ahmad, Ary Mustofa; Setyaningsih, Yeni Ika; Maharsih, Inggit Kresna; Sunyoto, Nimas Mayang Sabrina; Setyawan, Hendrix Yulis; Zhu, Mingming
    Purpose: This study aimed to investigate the influence of biochar supplementation in the mesophilic two-phase anaerobic digestion process for konjac waste. Methods: Reactors with a working volume of 60 mL were utilised to incubate cultures containing biochar. In the first phase, the cultures were maintained at 32 °C and a pH of 5 to facilitate the production of hydrogen. In the second phase, the cultures were adjusted to 37 °C and a pH of 7 to promote methane production. The concentration of konjac flour waste varied between 0 and 500 g/L, while the ratio of biochar addition ranged from 0 to 25 g/L. Biogas production was measured daily using the volume displacement method, and the pH of the cultures was monitored both before and after the experiment. Results: The findings show that using biochar has a beneficial effect on biogas production from konjac flour waste. During the initial phase of the experiment, incorporating biochar with a concentration of 15 g/L led to substantial improvements, elevating the maximum H2 production rates by 9.6%. Furthermore, the addition of biochar led to an 84% increase in H2 yield during the initial phase. Similarly, in the second phase, introducing biochar with a concentration of 15 g/L resulted in a 22.2% increase in the maximum CH4 production rates and a 2.5 times increase in CH4 yield. Conclusions: Overall, this work confirms the beneficial effects of biochar on the H2 and CH4 production from konjac flour waste using the mesophilic two-phase anaerobic digestion method for sustainable energy.
  • ItemOpen Access
    The road not taken yet: a review of cyber security risks in mobility-as-a-service (MaaS) ecosystems and a research agenda
    (Elsevier BV, 2024-10-01) Alderete Peralta, Ali; Balta-Ozkan, Nazmiye; Li, Shujun
    This paper identifies the state-of-the-art key aspects for the development of mobility-as-a-service (MaaS) ecosystems and provides evidence on the importance of cyber security which has been broadly overlooked in the literature. The analysis is carried out in three stages: (i) a literature review, (ii) a presentation of expert workshop findings, and (iii) a synthesis of both findings to develop a research agenda on cyber security aspects of MaaS ecosystems. The review identifies and bridges the gap between two strands of MaaS literature: the studies that focus on the factors that drive the development of MaaS, and those that create narratives of future MaaS scenarios. The analysis employs the Business Model Canvas to synthesise important factors that underline the development of MaaS in a 7-dimension matrix. This matrix is then used to assess to what extent the available MaaS scenarios cover such dimensions, showing that the literature has overlooked the incentives for users, incentives for MaaS providers, public governance and cyber security elements of the MaaS development. Finally, this paper synthesises the findings from the review of the literature and an expert workshop to develop a research agenda to characterise and analyse the role of incentives to influence the individuals' and organisations' data sharing preferences and emerging cyber security risks in MaaS ecosystems, which will be of interest to both scholars and policymakers. Only through explicit consideration of data-sharing behaviours and risks across individuals and organisations that MaaS ecosystems can support the transition to a net-zero economy.
  • ItemOpen Access
    Exploring agroforestry limiting factors and digitalization perspectives: insights from a european multi-actor appraisal
    (Springer Science and Business Media LLC, 2024-08-03) Tranchina, Margherita; Burgess, Paul; Cella, Fabrizio Giuseppe; Cumplido-Marin, Laura; Gosme, Marie; den Herder, Michael; Kay, Sonja; Lawson, Gerry; Lojka, Bohdan; Palma, João; Pardon, Paul; Reissig, Linda; Reubens, Bert; Prins, Evert; Vandendriessche, Jari; Mantino, Alberto
    Despite its potential for fostering farm sustainability, the adoption of agroforestry faces context-dependent challenges, among which the (perceived) shortage of decision-supporting tools and barriers hindering the assessment of economic, environmental, and social benefits. The process of digitalization offers significant opportunities to enhance sustainability, but it remains crucial to foster a human-centric, fair, and sustainable approach. In the context of the DigitAF Horizon Europe project, we present the results of a multi-stakeholder questionnaire aimed at understanding the perceptions of stakeholders regarding agroforestry and digitalization, as well as the needs of these stakeholders for a successful implementation of this agricultural practice. In the questionnaire, there was a specific focus on the need for and the conditions for the use of digital tools and models, such as generalized digital tools, applications and mapping, climate and weather forecasting and recording, farm management and decision support, and agroforestry and environmental tools. The purpose of this survey was to provide insights to inform agroforestry actors and to foster collaborative initiatives that enhance the potential of digital tools to support the design, implementation, and maintenance of effective and sustainable agroforestry in the European context. Our questionnaire was completed by stakeholders from seven European countries, including farmers, academics, policy actors, farm advisors, and actors in the value chain with an interest in agroforestry. Stakeholders from six living labs, representing Czechia, Finland, Germany, Italy, the Netherlands, and the UK, were involved in the appraisal, along with a multi-stakeholder group from Belgium. Respondents used data and digital tools for various purposes in farming systems and were interested in their potential to improve agroforestry including animal, tree, and crop performance, management guidance, system design, and tree species selection. Our survey revealed that the perceived usefulness of digital tools for agroforestry was substantially higher than stakeholders' awareness of existing tools, indicating a need for better promotion and development of user-friendly, accessible solutions. Additionally, significant obstacles to agroforestry adoption, such as large up-front investments, administrative burdens, and fear of reduced CAP support, were identified, emphasizing the necessity for targeted support and policy improvements. Moving forward, efforts should focus on developing targeted solutions to promote agroforestry according to stakeholder perception, and user-friendly digital tools tailored to the needs and preferences expressed by stakeholders, while also increasing knowledge sharing and capacity building among practitioners and researchers.
  • ItemOpen Access
    Flexible, scalable hierarchical graphene foam decorated with nickel layer for highly sensitive enzyme-free glucose sensing
    (Elsevier BV, 2024-11-05) Ji, Xiaodong; Jin, Huihui; Qian, Wei; Wang, Zhe; Zhang, Zixin; Yang, Zhugen; He, Daping
    Developing functional electrode materials for enzyme-free glucose electrochemical sensing is indispensable and challenging for rapid detection and instant diagnosis. Optimizing the microstructure of electrodes to enhance molecule accessibility, facilitate rapid mass transfer, and enlarge electrochemical active surface area is critical prerequisite for improving the electrochemical analytical performance. Herein, we develop a flexible graphene foam electrode with high conductivity and multilayer channel structure achieving efficient enzyme-free glucose sensor through one-step electrodeposition of nickel. The almost defect-free graphitic structure and layered multi-channel configuration enable the graphene foam to exhibit high conductivity, large specific surface area, and excellent mechanical performance. These properties result in efficient electron transmission and mass transfer, enabling the graphene foam to function as an excellent electrode substrate material in electrochemical sensors. Thus, the detecting electrode (Ni/GF) produced by electrodepositing nickel on graphene foam, demonstrates elevated sensitivity (1719.4 μA mM−1 cm−2), low limit of detection (0.2 μM), exceptional stability, and excellent flexibility for glucose detection. More importantly, the prepared electrode has been successfully applied to artificial sweat and tea, indicating its practical utility. The attractive analytical outcomes suggest that our layered multi-channel graphene foam has the potential to serve as a crucial foundational working electrode for designing efficient electrochemical sensor.
  • ItemEmbargo
    Modeling of dual‐factor drag correction model for bubbly flow under elevated pressure
    (Wiley, 2024-08) Gao, Yibo; Geng, Linlin; Verdin, Patrick G.; Fall, Ibra; Zhang, Ruijie; Tian, Zhongjie; Zhang, Desheng
    A pressure correction method is proposed considering the influence of a dual factor. The applicability of a pressure correction method coupled with a drag model is discussed along with the accuracy of the simulation results obtained by such a pressure correction method. It is found that the present pressure correction method combined with the DBS (dual bubble size) drag model can accurately reflect the changing trend of gas holdup distribution with pressure. It is also established that results from this model applied to a bubble column match well with the experimental data. Finally, when compared with other pressure correction models, the proposed model shows better robustness in three‐dimensional simulations and can predict radial gas holdup distributions with better accuracy.
  • ItemOpen Access
    Energy fluctuation of floating photovoltaic solar panel due to wave-induced motions
    (American Society of Mechanical Engineers, 2024-06-09) Huang, Luofeng
    Solar photovoltaic is predicted to be the most widely used energy method in the future. However, the expansion of solar panels is currently limited by scarce land and lake spaces. To meet the world’s future clean energy target, floating solar panels are expected to be deployed on abundant ocean space, but floating solar panels on the ocean will be subject to loads and motions induced by waves. In particular, a continuous rotation can cause the solar panel surface to constantly change its sunlight intake angle, which could lead to a loss of energy. To investigate this phenomenon, a novel interdisciplinary experimental facility has been established, where a solar simulator was installed on top of a wave tank. A floating solar unit is placed in high-concentration light beams and subject to wave-induced motions. Its motions are measured and related to the power output. It was found that the average power output oscillates due to the motions, and an evident power loss was shown by the rotational motion. For all the tested wave conditions, the highest pitch amplitude of 6.7° corresponds to a significant level of 12.7% average power loss. Overall, the work presents a novel experimental approach and results that can estimate power output for floating solar projects in wave environments. The results also highlight the importance of considering wave attenuation technologies to avoid direct wave interaction with floating solar units.
  • ItemOpen Access
    Compression after impact behavior of asymmetrically tapered laminates: experimental and numerical studies
    (Elsevier BV, 2024-12-01) Yu, Xiaonan; Xu, Xiwu; Huang, Luofeng; Qin, Qing; Zhang, Chao
    This paper presents experimental and numerical studies on the compression after impact (CAI) behavior of composite tapered laminates. It introduces newly designed impact platforms and compression fixtures specifically tailored for the specimens. Drop-weight impacts are applied to the center of the specimens, and the resulting damage is briefly described. Compression tests are then conducted on both non-impacted and impacted specimens, with strain gauges used to monitor the strain distribution. Internal damage is detected using CT scanning and ultrasonic C-scan techniques. The numerical simulations are performed using ABAQUS/Explicit finite element analysis (FEA), incorporating an intra-laminar progressive damage model and an inter-laminar cohesive model, while additionally modeling resin pockets as elastomers. The simulation and experimental results indicate that before compression failure, impact damage in the thin section minimally affects the out-of-plane displacement, which is predominantly influenced by structural asymmetry. Stress concentration is observed at the junction between the thin and tapered sections in the compression test, while in the CAI test, stress concentration appears in the impact zone. The impact induces a notable shift in failure location and damage modes, resulting in decreased compressive strength, although the impact on stiffness remains minimal.
  • ItemOpen Access
    Floating solar power loss due to motions induced by ocean waves: an experimental study
    (Elsevier BV, 2024-11-15) Huang, Luofeng; Yang, Yifeng; Khojasteh, Danial; Ou, Binjian; Luo, Zhenhua
    Whilst there is an interest in floating solar energy systems in coastal and offshore regions to utilise available sea space, they are subject to ocean waves that introduce constant momentum. Consequently, solar panels undergo periodic motions with the waves, causing a continuous change in tilt angle. The tilt angle variation is a sub-optimal process and leads to a loss of energy harnessing efficiency. To investigate this phenomenon, the present study innovatively installed a solar simulator on top of a wave tank. The solar simulator was used to generate high-strength light beams, under which, a floating solar unit was subject to periodic incident waves. Wave-induced motions to the solar system as well as the output power were measured. A systematic analysis of the results indicated that a floating solar unit can have significantly lower power output in waves, compared to its calm-water counterpart. An evident link was established between the wave-induced power loss and the wave-induced rotational movement of the panel. An empirical equation was derived which shows the power loss is predictable through the rotational amplitude. The results also highlight the importance of implementing wave attenuation technologies such as breakwaters to minimise wave-induced motions to floating solar systems. Overall, this research presents a novel experimental approach to assess the difference of floating solar power in ocean-wave versus calm-water scenarios, providing valuable insights for future solar projects on the ocean.
  • ItemOpen Access
    Interactive effects of deformable wave energy converters operating in close proximity
    (Elsevier BV, 2024-11-01) Wang, Chao; Wei, Yujia; Chen, Wenchuang; Huang, Luofeng
    Flexible wave energy converters (FlexWECs) have been gaining increasing research and industrial interest as their deformable nature can potentially remedy the structural issues that limit the development of rigid WECs. To maximise the usage of space and infrastructure and improve energy efficiency, FlexWECs are normally deployed in close proximity, where the wave interaction with one device can influence others, signifying the opportunity to obtain energy efficiency enhancement from the interactions. To investigate the power capture performance of a FlexWEC array, this study employed a validated three-dimensional high-fidelity computational method to simulate the wave interaction with three FlexWECs in various array arrangements including power-take off. Based on systematic simulation cases, the present work analysed the relation between the geometrical characteristics of an isolated FlexWEC's perturbed wave field and the array's overall energy capture efficiency. The constructive interaction of the array was found the strongest when the longitudinal and lateral spacings of the array were 0.6 and 1 times of incident wavelength respectively, with a 15 % enhancement of overall captured energy compared to three devices operating in isolation. Overall, this study provides insights into the fluid-structure interaction of waves with multiple deformable structures, facilitating the modelling and planning of FlexWECs.
  • ItemOpen Access
    Effect of platform configurations and environmental conditions on the performance of floating solar photovoltaic structures
    (TU Delft OPEN Publishing, 2024-05-20) Jifaturrohman, MI; Putranto, T; Utama, IKAP; Huang, L
    The growth and development of floating solar photovoltaic (FPV) power plants is a prominent topic within renewable energy technology. One reason contributing to this desired technology design concept is the possibility of land acquisition issues, whereas the usage of the ocean provides a greater technical alternative area. The objective of the research is to present an innovative design for a floating structure, focusing on investigating and comparing the seakeeping performance of several hull configurations: catamaran, trimaran, quadrimaran and pentamaran. The final computational simulation results indicate a linear negative trend in the motion response graphs, particularly in specific significant response values for heave (Global Z), roll (Global RX), and pitch (Global RY), as the hull configuration increases.
  • ItemOpen Access
    Motion response and energy harvesting of multi-module floating photovoltaics in seas
    (Elsevier BV, 2024-10-15) Zheng, Zhi; Jin, Peng; Huang, Qiang; Zhou, Binzhen; Xiang, Ruoxuan; Zhou, Zhaomin; Huang, Luofeng
    Floating Photovoltaic (FPV) systems are emerging as a new type of ocean renewable energy, offering advantages such as avoiding land use and promoting power generation efficiency. Providing significant cost-effectiveness for manufacturing, transportation, and installation, FPV systems with modular floating platforms exhibit the potential to replace the conventional large steel-frame one. However, the performance of such multi-floating body structures under wave conditions remain underexplored. In this paper, based on potential flow theory, the motion characteristics and power performance of the proposed FPV array connected by the articulated system are evaluated. The results indicate that the FPV arrays with shorter floating structures exhibit greater pitch motion, especially when the wave condition matches the pitch resonance. For multi-float cases, the articulated system, optimized with appropriate parameters, demonstrates efficacy as attenuators. Additionally, the proposed FPV array has great potential to serve as an infrastructure for integrating solar and wave energy. For a selected offshore site, potential wave energy output from motion attenuators between FPV floaters is assessed together with solar energy output. Overall, this study serves as a valuable reference for the design and optimization of the multi-modules FPV and advances the research on combined solar and wave energy utilization on floating structures.
  • ItemOpen Access
    Detection of sugar syrup adulteration in UK honey using DNA barcoding
    (Elsevier BV, 2025-01-01) Dodd, Sophie; Kevei, Zoltan; Karimi, Zahra; Parmar, Bhavna; Franklin, David; Koidis, Anastasios; Anastasiadi, Maria
    Honey is a valuable and nutritious food product, but it is at risk to fraudulent practices such as the addition of cheaper syrups including corn, rice, and sugar beet syrup. Honey authentication is of the utmost importance, but current methods are faced with challenges due to the large variations in natural honey composition (influenced by climate, seasons and bee foraging), or the incapability to detect certain types of plant syrups to confirm the adulterant used. Molecular methods such as DNA barcoding have shown great promise in identifying plant DNA sources in honey and could be applied to detect plant-based sugars used as adulterants. In this work DNA barcoding was successfully used to detect corn and rice syrup adulteration in spiked UK honey with novel DNA markers. Different levels of adulteration were simulated (1 – 30%) with a range of different syrup and honey types, where adulterated honey was clearly separated from natural honey even at 1% adulteration level. Moreover, the test was successful for multiple syrup types and effective on honeys with different compositions. These results demonstrated that DNA barcoding could be used as a sensitive and robust method to detect common sugar adulterants and confirm syrup species origin in honey, which can be applied alongside current screening methods to improve existing honey authentication tests.
  • ItemEmbargo
    Biodegradation of oily waste sludge using vermiremediation and composting process bioaugmentated with isolated hydrocarbon-degrading bacteria: performance and ecotoxicity assessment
    (Elsevier BV, 2024-12-01) Alinoori, Maral; Saeedi, Reza; Coulon, Frederic; Villaseñor, José; Goodini, Kazem; Ghamari, Farhad; Hesampoor, Faezeh; Asghari, Fatemeh; Sartaj, Majid; Koolivand, Ali
    Degradation of petroleum hydrocarbons (PHs) contents of oily waste sludge (OWS) is necessary in order to prevent the related environmental pollution. The present study aimed to investigate the degradation of total petroleum hydrocarbons (TPHs) from OWS using bioaugmentated composting (BC) with hydrocarbon-degrading bacterial consortium (HDBC) as pre-treatment followed by vermicomposting (VC) by Eisenia fetida. After isolating two indigenous bacterial strains from OWS, the ability of their consortium in degradation of crude oil was tested in Bushnell-Haas medium (BHM). Then, biodegradation of OWS was measured in the VC alone, BC alone, simultaneous BC and VC (BCVC), and BC followed by VC (BCFVC) containing high levels (30 g/kg) of TPHs. Toxicity tests including the mortality of mature earthworms and the numbers of juveniles were conducted at the TPHs of 0–40 g/kg. The obtained results indicated that the HDBC removed 18–64 % of TPHs of crude oil (1–5 %) in BHM after 7 days of incubation. After a period of 12 weeks, the removal rates of TPHs in the VC, BC, BCVC, and BCFVC experiments were 23.7, 79.5, 85.2, and 91.8 %, respectively, verifying the efficacy of simultaneous application of HDBC and worms in bioremediation of OWS. The TPHs contents of OWS exhibited toxic effects on E. fetida at some concentrations and the median lethal concentration (LC50) of TPHs was computed to be 14.5 g/kg after 28 days. This study demonstrated the effectiveness of composting bioaugmentated with HDBC as a pre-treatment step followed by vermicomposting in bioremediation of OWS.
  • ItemOpen Access
    Uncovering the impact of metals on the formation and physicochemical properties of fat, oil and grease deposits in the sewer system
    (Elsevier BV, 2024-09-01) Yusuf, Hamza Hassan; Roddick, Felicity; Jegatheesan, Veeriah; Jefferson, Bruce; Gao, Li; Pramanik, Biplob Kumar
    The deposition of fats, oil, and grease (FOG) in sewers reduces conveyance capacity and leads to sanitary sewer overflows. The major contributing factor lies in the indiscriminate disposal of used cooking oil (UCO) via kitchen sinks. While prior investigations have mostly highlighted the significance of Ca2+ from concrete biocorrosion, the influence of common metal ions (e.g., Mg2+, Na+, K+) found in kitchen wastewater on FOG deposition has received limited attention in the existing literature. This study aimed to elucidate the roles of Ca, Mg, Na and K in FOG deposition in sewers and examine the influence of metal ions, fat/oil sources, and free fatty acids (FFAs) on the physicochemical and rheological properties of FOG deposits. To examine FOG deposit formation, synthetic wastewater containing 0.1 g/L of each metal ion was mixed with 40 mL of fat/oil and agitated for 8 h. Following FOG deposition, three distinct phases were observed: unreacted oil, FOG deposit and wastewater. The composition of these phases was influenced by the composition of metal ions and FFA in the wastewater. Mg produced the highest amount of FOG of 242.5 ± 10.6 mL compared to Ca (72.5 ± 3.5 mL) when each FFAs content in UCO was increased by 10 mg/mL. Molar concentration, valency and the solubility of metal ion sources were identified to influence the formation of FOG deposits via saponification and aggregation reaction. Furthermore, Fourier-Transform Infrared spectroscopy indicated that the FOG deposits in this study were similar to those collected from the field. This study showed that the use of Mg(OH)2 as a biocorrosion control measure would increase FOG deposition and highlights the need for a comprehensive understanding of its roles in real sewage systems.
  • ItemOpen Access
    Hydroelastic modelling of a deformable wave energy converter including power take-off
    (Elsevier, 2024-11-01) Wang, Chao; Wei, Yujia; Chen, Wenchuang; Huang, Luofeng
    Given the advantages of flexible wave energy converters (FlexWECs), such as deformation-led energy harnessing and structural loading compliance, there has been a significant interest in FlexWECs in both academia and industries. To simulate the FlexWEC interaction with ocean surface waves, a 3D computational fluid-structure interaction approach is developed in this study. The fluid and solid governing equations are discretized using finite difference and finite element methods, respectively. An immersed boundary method is used to couple the two independent grid systems. A novel numerical technique is introduced to model the dielectric elastomer generator (DEG) as the power take-off (PTO). The wave energy capture performance is analysed for different PTO configurations and at various wave conditions. Based on the obtained results, the PTO damping coefficient and the relative wavelength range that maximizes the capture width ratio (CWR) are determined. The wavefield results also reveal the presence of wave-height enhancement and attenuation points around a single FlexWEC, providing potential site selection references when deploying multiple FlexWECs in an array.
  • ItemOpen Access
    Impact of Irpex lenis and Schizophyllum commune endophytic fungi on Perilla frutescens: enhancing nutritional uptake, phytochemicals, and antioxidant potential
    (Springer Science and Business Media LLC, 2024-12-01) Sharma, Kiran; Verma, Rachna; Kumar, Dinesh; Kumar, Vinod
    Background: Endophytic fungi (EF) reside within plants without causing harm and provide benefits such as enhancing nutrients and producing bioactive compounds, which improve the medicinal properties of host plants. Selecting plants with established medicinal properties for studying EF is important, as it allows a deeper understanding of their influence. Therefore, the study aimed to investigate the impact of EF after inoculating the medicinal plant Perilla frutescens, specifically focusing on their role in enhancing medicinal properties. Results: In the current study, the impact of two EF i.e., Irpex lenis and Schizophyllum commune isolated from A. bracteosa was observed on plant Perilla frutescens leaves after inoculation. Plants were divided into four groups i.e., group A: the control group, group B: inoculated with I. lenis; group C: inoculated with S. commune and group D: inoculated with both the EF. Inoculation impact of I. lenis showed an increase in the concentration of chlorophyll a (5.32 mg/g), chlorophyll b (4.46 mg/g), total chlorophyll content (9.78 mg/g), protein (68.517 ± 0.77 mg/g), carbohydrates (137.886 ± 13.71 mg/g), and crude fiber (3.333 ± 0.37%). Furthermore, the plants inoculated with I. lenis showed the highest concentrations of P (14605 mg/kg), Mg (4964.320 mg/kg), Ca (27389.400 mg/kg), and Mn (86.883 mg/kg). The results of the phytochemical analysis also indicated an increased content of total flavonoids (2.347 mg/g), phenols (3.086 mg/g), tannins (3.902 mg/g), and alkaloids (1.037 mg/g) in the leaf extract of P. frutescens inoculated with I. lenis. Thus, overall the best results of inoculation were observed in Group B i.e. inoculated with I. lenis. GC-MS analysis of methanol leaf extract showed ten bioactive constituents, including 9-Octadecenoic acid (Z)-, methyl ester, and hexadecanoic acid, methyl ester as major constituents found in all the groups of P. frutescens leaves. The phenol (gallic acid) and flavonoids (rutin, kaempferol, and quercetin) were also observed to increase after inoculation by HPTLC analysis. The enhancement in the phytochemical content was co-related with improved anti-oxidant potential which was analyzed by DPPH (% Inhibition: 83.45 µg/ml) and FRAP (2.980 µM Fe (II) equivalent) assay as compared with the control group. Conclusion: Inoculation with I. lenis significantly enhances the uptake of nutritional constituents, phytochemicals, and antioxidant properties in P. frutescens, suggesting its potential to boost the therapeutic properties of host plants. Graphical Abstract: (Figure presented.)
  • ItemOpen Access
    The effect of hydrogen fuel on the performance and emissions of 3 kWe natural gas fuelled microturbine
    (Elsevier BV, 2024-11-15) Jomekian, Abolfazl; Alhasnawi, Bilal Naji; Bazooyar, Bahamin; Nabavi, Ali; Varasteh, Hirbod
    Hydrogen is an alternative fuel to power microturbines. In this work, the application of H2 in a 3 kWe microturbine combustor is investigated. First, the combustor is tested with different molar concentrations of hydrogen in methane fuel (XH2= 5%, 10% and 20%). Afterward, the operation of the microturbine is verified using thermodynamic analysis of the microturbine cycle. The combustion of the fuels is investigated using CFD analysis. The level of gaseous emissions including (CO2, CO, and NOX) and the microturbine overall operability in terms of turbomachine mechanical and thermal efficiencies are compared in each case to find out the influence of hydrogen addition on the natural gas combustion in the microturbine (MT). Findings show that the application of hydrogen in the MT combustor decreases the level of CO2 and CO emissions while increasing NOX emissions. Despite the improvement in combustion, hydrogen could deteriorate the MT effectiveness and overall efficiency. The findings demonstrate that if the hydrogen mole percent in the fuel rises from 0 to 10, the cycle efficiency decreases from 4.73% to 4.7% and if it increases to 20 percent, the efficiency of the cycle increases from 4.7% to 4.92%.
  • ItemOpen Access
    Long-range hydrological drought forecasting using multi-year cycles in the North Atlantic Oscillation
    (Elsevier BV, 2024-09) Rust, William; Bloomfield, John P.; Holman, Ian
    With global temperatures, populations and ecological stressors expected to rise, hydrological droughts are projected to have progressively severe economic and environmental impacts. As a result, hydrological drought forecasting systems have become increasingly important water resource management tools for mitigating these impacts. However, high frequency behaviours in meteorological or atmospheric conditions often limit the lead times of hydrological drought forecasts to seasonal timescales, either through poorer performance of multi-year meteorological forecasts or the lack of multi-year lags in atmosphere-hydrology systems. By contrast, low frequency behaviours in regionally important teleconnection systems (such as the North Atlantic Oscillation, NAO) offer a novel way to forecast hydrological drought at longer lead times. This paper shows that, by using a data-driven modelling approach, long-term behaviours within the NAO can be skilful predictors of hydrological drought conditions at a four-year forecasting horizon. Multi-year semi-periodic patterns in the NAO were used to forecast regional groundwater drought coverage in the UK (proportion of groundwater boreholes in drought), with the greatest forecast performance achieved for longer duration droughts, and for hydrogeological regions with longer response times. Model errors vary from 14 % (proportion of boreholes, (MAE)) in flashy hydrological regions or short droughts (<3 months), to 2 % for longer duration droughts (>8 months). Model fits of r2 up to 0.8 were produced between simulated and recorded regional drought coverage. As such our results show that teleconnection indices can be a skilful predictor of hydrological drought dynamics at multi-year timescales, opening new opportunities for long-lead groundwater drought forecasts to be integrated within existing drought management strategies in Europe and beyond.