| 1. |
- Badr, Hussein O., et al.
(författare)
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Bottom-up, scalable synthesis of anatase nanofilament-based two-dimensional titanium carbo-oxide flakes
- 2022
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Ingår i: Materials Today. - : ELSEVIER SCI LTD. - 1369-7021 .- 1873-4103. ; 54
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Tidskriftsartikel (refereegranskat)abstract
- Two-dimensional (2D) materials offer advantages that their 3D counterparts do not. The conventional method for the bulk synthesis of 2D materials has predominantly been through etching layered solids. Herein, we convert - through a bottom-up approach - 10 binary and ternary titanium carbides, nitrides, borides, phosphides, and silicides into 2D flakes by immersing them in a tetramethylammonium hydroxide solution at temperatures in the 25-85 degrees C range. Based on X-ray diffraction, density functional theory, X-ray photoelectron, electron energy loss, Raman, X-ray absorption near edge structure spectroscopies, transmission and scanning electron microscope images and selected area diffraction, we conclude that the resulting flakes are carbon containing anatase-based layers that are, in turn, comprised of approximate to 6 x 10 angstrom(2) nanofilaments in cross-section some of which are few microns long. Electrodes made from some of these films performed well in lithium-ion and lithium-sulphur systems. These materials also reduce the viability of cancer cells thus showing potential in biomedical applications. Synthesizing 2D materials, at near ambient conditions, with non-layered, inexpensive, green precursors (e.g., TiC) is paradigm shifting and will undoubtedly open new and exciting avenues of research and applications.
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| 2. |
- Fachrizal, Reza, 1993-, et al.
(författare)
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Urban-scale energy matching optimization with smart EV charging and V2G in a net-zero energy city powered by wind and solar energy
- 2024
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Ingår i: eTransporation. - : Elsevier. - 2590-1168. ; 20
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Tidskriftsartikel (refereegranskat)abstract
- Renewable energy sources (RES) and electric vehicles (EVs) are two promising technologies that are widely recognized as key components for achieving sustainable cities. However, intermittent RES generation and increased peak load due to EV charging can pose technical challenges for the power systems. Many studies have shown that improved load matching through energy system optimization can minimize these challenges. This paper assesses the optimal urban-scale energy matching potentials in a net-zero energy city powered by wind and solar energy, considering three EV charging scenarios: opportunistic charging, smart charging, and vehicle-to-grid (V2G). This paper takes a city on the west coast of Sweden as a case study. The smart charging and V2G schemes in this study aim to minimize the mismatch between generation and load and are formulated as quadratic programming problems. Results show that the optimal load matching performance is achieved in a net-zero energy city with the V2G scheme and a wind-PV electricity production share of 70:30. The load matching performance is increased from 68% in the opportunistic charging scenario to 73% in the smart charging scenario and to 84% in the V2G scenario. It is also shown that a 2.4 GWh EV battery participating in the V2G scheme equals 1.4 GWh stationary energy storage in improving urban-scale load matching performance. The findings in this paper indicate a high potential from EV flexibility in improving urban energy system performance.
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| 3. |
- Gao, Yun, et al.
(författare)
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Region separation type bio-photoelectrode based all-solid-state self-powered aptasensor for ochratoxin A and aflatoxin B1 detection
- 2022
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Ingår i: Sensors and actuators. B, Chemical. - : Elsevier. - 0925-4005 .- 1873-3077. ; 364
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Tidskriftsartikel (refereegranskat)abstract
- Ochratoxin A (OTA) and Aflatoxin B1 (AFB1) are two highly toxic and naturally coexistence mycotoxins, which have posed a serious threat to food safety. The coexistence of these two mycotoxins can produce significant synergistic effects, so it is necessary to establish an effective analytical method. In this work, a dual biophotoelectrode based all-solid-state multiplexed self-powered aptasensor was realized for high-throughput analysis of OTA and AFB1. There was a large Fermi level difference between photoanode and photocathode, which ensured the light assisted self-driving of the system. Due to the regional immobilization of aptamers, it could save the dosage of recognition elements, reduce the preparation cost and simplify the operation procedure. Meanwhile, construction strategy of spatial separation could effectively eliminate the overlapping signals and cross interference between targets, achieving the results more accurate and the calculation more convenient. The constructed aptasensor realized OTA and AFB1 detection in corn samples with practicality, good stability, antiinterference ability and repeatability. Therefore, this work not only achieved the high-throughput analysis of mycotoxins, but also provided a new perspective for the construction of all-solid-state multiplexed self-powered sensor.
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| 4. |
- He, Yafang, et al.
(författare)
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Metabolomic Changes Upon Conjugated Linoleic Acid Supplementation and Predictions of Body Composition Responsiveness
- 2022
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 107:9, s. 2606-2615
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Tidskriftsartikel (refereegranskat)abstract
- Context Conjugated linoleic acid (CLA) may optimize body composition, yet mechanisms underlining its benefits are not clear in humans. Objective We aimed to reveal the CLA-induced changes in the plasma metabolome associated with body composition improvement and the predictive performance of baseline metabolome on intervention responsiveness. Methods Plasma metabolome from overnight fasted samples at pre- and post-intervention of 65 participants in a 12-week randomized, placebo-controlled trial (3.2 g/day CLA vs 3.2 g/day sunflower oil) were analyzed using untargeted LC-MS metabolomics. Mixed linear model and machine learning were applied to assess differential metabolites between treatments, and to identify optimal panel (based on baseline conventional variables vs metabolites) predicting responders of CLA-derived body composition improvement (increased muscle variables or decreased adiposity variables) based on dual-energy x-ray absorptiometry. Results Compared with placebo, CLA altered 57 metabolites (P
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| 5. |
- Qian, Kun, et al.
(författare)
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An eye tracking based virtual reality system for use inside magnetic resonance imaging systems
- 2021
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322 .- 2045-2322. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- Patients undergoing Magnetic Resonance Imaging (MRI) often experience anxiety and sometimes distress prior to and during scanning. Here a full MRI compatible virtual reality (VR) system is described and tested with the aim of creating a radically different experience. Potential benefits could accrue from the strong sense of immersion that can be created with VR, which could create sense experiences designed to avoid the perception of being enclosed and could also provide new modes of diversion and interaction that could make even lengthy MRI examinations much less challenging. Most current VR systems rely on head mounted displays combined with head motion tracking to achieve and maintain a visceral sense of a tangible virtual world, but this technology and approach encourages physical motion, which would be unacceptable and could be physically incompatible for MRI. The proposed VR system uses gaze tracking to control and interact with a virtual world. MRI compatible cameras are used to allow real time eye tracking and robust gaze tracking is achieved through an adaptive calibration strategy in which each successive VR interaction initiated by the subject updates the gaze estimation model. A dedicated VR framework has been developed including a rich virtual world and gaze-controlled game content. To aid in achieving immersive experiences physical sensations, including noise, vibration and proprioception associated with patient table movements, have been made congruent with the presented virtual scene. A live video link allows subject-carer interaction, projecting a supportive presence into the virtual world.
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| 6. |
- Qian, Kun, et al.
(författare)
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Large-scale EV charging scheduling considering on-site PV generation by combining an aggregated model and sorting-based methods
- 2024
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Ingår i: Sustainable cities and society. - : Elsevier. - 2210-6707. ; 107
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Tidskriftsartikel (refereegranskat)abstract
- Large-scale electric vehicle (EV) charging scheduling is highly relevant for the growing number of EVs, while it can be complex to solve. A few existing studies have applied a two-stage scheduling approach to reduce computation time. The first stage approximates the optimal overall load, and the second prioritizes the charging. This work also attempts to apply such an approach for large-scale EV charging considering on-site photovoltaic (PV) generation at a workplace. However, validation and analysis are missing to address whether and why the two-stage approach is suitable. Besides, the existing studies lack exploring different methods to prioritize charging. This work investigates the two-stage approach. Simulation results show the non-uniqueness of the optimal solution from the optimal individual model, and guided by the optimal overall load, sorting-based methods can often lead to an optimal solution, while non-optimal solutions only cause decreases in the load-matching performance with a median value of less than 1%. The aggregated model usually cannot achieve the optimal overall load due to model simplifications. However, further applying sorting-based methods will reduce the differences between the final and the optimal overall load. Thus, the two-stage approach is suitable for this study, and further simulations show that it can achieve almost the optimal annual performance with around 1/57 of the computation time. Furthermore, this study explores different methods to prioritize charging. Simulation results show no difference in performance, while the Least Laxity First method leads to around 54.6% more switching.
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| 7. |
- Qian, Kun, et al.
(författare)
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The Impact of Considering State of Charge Dependent Maximum Charging Powers on the Optimal Electric Vehicle Charging Scheduling
- 2023
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Ingår i: IEEE Transactions on Transportation Electrification. - : Institute of Electrical and Electronics Engineers (IEEE). - 2332-7782 .- 2372-2088. ; 9:3, s. 4517-4530
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Tidskriftsartikel (refereegranskat)abstract
- Intelligent charging solutions facilitate mobility electrification. Mathematically, electric vehicle (EV) charging scheduling formulations are constrained optimization problems. Therefore, accurate constraint modeling is theoretically and practically relevant for scheduling. However, the current scheduling literature lacks an accurate problem formulation, including the joint modeling of the nonlinear battery charging profile and minimum charging power constraints. The minimum charging power constraint prevents allocating inexecutable charging profiles. Furthermore, if the problem formulation does not consider the battery charging profile, the scheduling execution may deviate from the allocated charging profile. An insignificant deviation indicates that simplified modeling is acceptable. After providing the problem formulation targeting the maximum possible vehicle battery state of charge (SoC) on departure, the numerical assessment shows how the constraint consideration impacts the scheduling performance in typical charging scenarios (weekday workplace and weekend public charging where the grid supplies up to forty vehicles). The simulation results show that the nonlinear battery charging constraint is practically negligible: For many connected EVs, the grid limit frequently overrules that constraint. The resulting difference between the final mean SoCs using and not using accurate modeling does not exceed 0.2%. Consequently, the results justify simplified modeling (excluding the nonlinear charging profile) for similar scenarios in future contributions.
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| 8. |
- Qian, Kun, et al.
(författare)
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Validating and Improving an Aggregated EV Model for Energy Systems Evaluation
- 2023
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Ingår i: 2023 11th International Conference on Smart Grid, icSmartGrid. - Paris : IEEE. - 9798350310665 - 9798350310672
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Konferensbidrag (refereegranskat)abstract
- With the trend in transportation electrification, electric vehicle (EV) charging/discharging scheduling has become an area of concern. Scheduling can help manage EV charging/discharging activities. Besides, it is also valuable for energy systems evaluation, in which case modeling the individual EV has high complexity and requires a long computation time due to too many EVs. The aggregated model significantly reduces computation time but may sacrifice accuracy. This work investigates the trade-off between accuracy and computational time when designing intelligent EV charging/discharging scheduling by comparing the individual and aggregated models. This work first provides a detailed problem formulation. The simulation results show that the aggregated model can achieve similar energy system performance estimations from the energy-matching perspective compared to the individual model, given that the system allows vehicle-to-grid (V2G). Otherwise, the aggregated model will overestimate the performance. Thus, this work, in the meantime, proposes an extra constraint to avoid such overestimation when V2G is not allowed. Given the validated accuracy of the aggregated model and its advantage of low complexity and computation time, the aggregated model is more suitable for assessing large (e.g., city-level) energy systems.
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| 9. |
- Qin, Shun-Shun, et al.
(författare)
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Dual-functional ionic porous organic framework for palladium scavenging and heterogeneous catalysis
- 2021
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Ingår i: Nanoscale. - : Royal Society of Chemistry. - 2040-3364 .- 2040-3372. ; 13:7, s. 3967-3973
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Tidskriftsartikel (refereegranskat)abstract
- Porous organic frameworks (POFs) with predesigned structures and tunable porosities have been widely studied in adsorption and heterogeneous catalysis. Introducing ionic structure into the framework endows POFs with new functionalities that may extend their applications. Here, we report new applications for a guanidinium-based ionic POF (IPOF-Cl) in palladium scavenging and heterogeneous catalysis. Due to the ionic framework and the porous structure, the IPOF-Cl displays fast adsorption kinetics and high adsorption capacities (up to 754 mg g−1) of Na2PdCl4 in aqueous solutions via a chemisorption (ion exchange) process. Significantly, it shows excellent scavenging activity towards trace amount of [PdCl4]2− in aqueous solution. More importantly, the loaded [PdCl4]2− species on the IPOF substrate are further reduced into ultrafine Pd nanoparticles with size of ∼2–5 nm. The obtained IPOF-Pd(0) nanocomposite containing uniformly distributed Pd nanoparticles and hierarchical porous structure demonstrates high activity in catalyzing a range of Suzuki coupling reactions. This study provides new routes for the development of ionic porous organic materials for applications in metal scavenging and catalysis.
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| 10. |
- Shao, Wen-Ze, et al.
(författare)
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DeblurGAN plus : Revisiting blind motion deblurring using conditional adversarial networks
- 2020
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Ingår i: Signal Processing. - : ELSEVIER. - 0165-1684 .- 1872-7557. ; 168
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Tidskriftsartikel (refereegranskat)abstract
- This work studies dynamic scene deblurring (DSD) of a single photograph, mainly motivated by the very recent DeblurGAN method. It is discovered that training the generator alone of DeblurGAN will result in both regular checkerboard effects and irregular block color excursions unexpectedly. In this paper, two aspects of endeavors are made for a more effective and robust adversarial learning approach to DSD. On the one hand, a kind of opposite-channel -based discriminative priors is developed, improving the deblurring performance of DeblurGAN without additional computational burden in the testing phase. On the other hand, a computationally more efficient while architecturally more robust auto -encoder is developed as a substitute of the original generator in DeblurGAN, promoting DeblurGAN to a new state-of-the-art method for DSD. For brevity, the proposed approach is dubbed as DeblurGAN+. Experimental results on the benchmark GoPro dataset validate that DeblurGAN+ achieves more than 1.5 dB improvement than DeblurGAN in terms of PSNR as trained utilizing the same amount of data. More importantly, the results on realistic non -uniform blurred images demonstrate that DeblurGAN+ is really more effective than DeblurGAN as well as most of variational model-based methods in terms of both blur removal and detail recovery.
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