Recent years have witnessed the flourish of new promising technologies to prolong the lifetime of wireless sensor networks (WSNs). Employing mobile vehicles for wireless charging and data collection ...is able to balance the load of WSNs, and meanwhile, provide a reliable energy replenishment for sustainable network operations. Different from traditional charging scheduling policies where sensor nodes passively wait for the arrival of mobile vehicles, a novel dynamic clustering based mobile-to-cluster (M2C) scheme is proposed to optimize the service process for both sensor nodes and the vehicle in an active way. Requiring only local residual energy information, M2C refreshes the cluster-based network topology to ensure no sensor nodes will run out of energy before getting charged. By estimating the energy consumption of being a cluster head, the sensor nodes with residual energy close to the estimation are actively elected as head nodes. More head nodes with low residual energy will be visited, reducing the travel distance along with higher energy efficiency of charging. Furthermore, the convergence and worst-case performance of M2C are theoretically analyzed. Performance evaluation results show that compared with the state-of-the-art schemes, our design reduces the travel distance and charging latency by about 10% and 50%, respectively.
Layered double hydroxide materials with sheet-like morphologies (i.e., LDH nanosheets) have been proposed to use in supercapacitors. However, the practical application of LDH nanosheets has been ...inhibited by the notorious inter-particle aggregation and poor charge transport between active materials and current collectors. In this work, 3D nickel-iron layered double hydroxide (NiFe-LDH) nanosheet films with porous nanostructures were synthesized using a hydrothermal method. The ultrathin nanosheets are homogeneously and vertically aligned on the surface of Ni foam. The pseudocapacitors assembled using NiFe-LDH nanosheets exhibit a superior specific capacitance of 2708 F g−1 at 5 A g−1, higher than the previously reported LDHs. The effect of growth concentration and Ni/Fe mole ratio on the electrochemical properties was also investigated. Asymmetric supercapacitors with the NiFe-LDH nanosheets film as the positive electrode and active carbon as the negative electrode display a high energy density of 52 Wh kg−1 at an average power density of 800 W kg−1. When two aqueous asymmetric supercapacitors were assembled in series and charged for only 1 min, the stored energy was capable of powering two green light-emitting-diodes for more than 5 min, indicating the great potential of these 3D NiFe-LDH nanosheets for high-performance energy storage.
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•3D ultrathin NiFe-LDH nanosheets were prepared on Ni foam.•The specific capacitance of NiFe-LDH-based electrode is 2708 F/g at 5 A/g.•The asymmetric supercapacitor exhibited a high energy density and power density.•The asymmetric supercapacitors can power two LED more than 5 min after charging for 1 min.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The solid-state method is a mainly adopted large-scale preparation of LiFePO
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cathode materials for Li-ion batteries but suffers from a challenge of irregular morphology and particle agglomeration. ...Herein, a graphene-supported LiFePO
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/C@G composite with uniform morphology and electronic conducting network was synthesized via a freeze-drying assisted solid-state method without ball milling using the integrated LiFePO
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(OH) as precursor. The integrated LiFePO
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(OH) as precursor may avoid segregation of element caused by inhomogeneous mixing of raw materials in the process of solid-state preparation. The as-prepared graphene-coated LiFePO
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/C@G shows excellent electrochemical properties with a specific capacity of 156, 154, 150, 145, 139, 132 mA h g
−1
at 0.1, 0.2, 0.5, 1, 2, 5 C and a capacity retention of around 97.0% for 200 cycles at 2 C. This can be attributed to uniform element distribution and continuous electronic conducting network. The freeze-drying assisted solid-phase method using LiFePO
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(OH) precursor and graphene is a promising route for production of LiFePO
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/C materials with excellent performances.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Purpose In recent years, augmented reality (AR) has shown its potential to assist various construction activities. Its use commonly requires additional refinement to be integrated into the building ...information modeling (BIM) process. Nevertheless, few studies have investigated AR implementation in BIM-enabled projects because of numerous challenges related to its implementation. This study aims to investigate the implementation of AR in construction and identify the critical mechanisms for implementing BIM-AR successfully. Design/methodology/approach A mixed methodology was adopted for this study. First, this work presents a bibliometric analysis covering articles obtained from Scopus database published between 2000 and 2022. A sample size of 65 research papers pertinent to AR in construction was analyzed using VOSviewer software. Second, a participatory case study was conducted for a BIM-enabled project in China to gain insight into how BIM-AR implementation in construction is achieved. Findings The findings from the bibliometric analysis show an increasing interest in AR research within construction. The results indicate that AR research focuses on four clusters: real-time communication, project management, construction activities and education. Findings from the case study provide an empirical experience of AR application scenarios in a BIM-enabled project. Concomitantly, 15 critical success factors that influence BIM-AR implementation were finally identified and demonstrated. Originality/value This study provides a rich insight into the understanding and awareness of implementing AR. First, the findings are beneficial to construction practitioners and researchers because they provide a concentrated perspective of AR for emerging activities in the construction industry. Second, the results obtained from the case study could provide a useful guide for effectively implementing AR in a BIM-enabled construction project. Overall, this study may stimulate further research on AR-related studies in construction, such as BIM integration, factor analysis and construction education.
It is a grand challenge to deep understanding of and precise control over functional sites for the rational design of highly efficient catalysts for methanol electrooxidation. Here, an L12-Pt2RhFe ...intermetallic catalyst with integrated functional components is demonstrated, which exhibits exceptional CO tolerance. The Pt2RhFe/C achieves a superior mass activity of 6.43 A mgPt -1, which is 2.23-fold and 3.53-fold higher than those of PtRu/C and Pt/C. Impressively, the Pt2RhFe/C exhibits a significant enhancement in durability owing to its high CO-tolerance and stability. Density functional theory calculations reveal that high performance of Pt2RhFe intermetallic catalyst arises from the synergistic effect: the strong OH binding energy (OHBE) at Fe sites induce stably adsorbed OH species and thus facilitate the dehydrogenation step of methanol via rapid hydrogen transfer, while moderate OHBE at Rh sites promote the formation of the transition state (Pt-CO···OH-Rh) with a low activation barrier for CO removal. This work provides new insights into the role of OH binding strength in the removal of CO species, which is beneficial for the rational design of highly efficient catalysts.It is a grand challenge to deep understanding of and precise control over functional sites for the rational design of highly efficient catalysts for methanol electrooxidation. Here, an L12-Pt2RhFe intermetallic catalyst with integrated functional components is demonstrated, which exhibits exceptional CO tolerance. The Pt2RhFe/C achieves a superior mass activity of 6.43 A mgPt -1, which is 2.23-fold and 3.53-fold higher than those of PtRu/C and Pt/C. Impressively, the Pt2RhFe/C exhibits a significant enhancement in durability owing to its high CO-tolerance and stability. Density functional theory calculations reveal that high performance of Pt2RhFe intermetallic catalyst arises from the synergistic effect: the strong OH binding energy (OHBE) at Fe sites induce stably adsorbed OH species and thus facilitate the dehydrogenation step of methanol via rapid hydrogen transfer, while moderate OHBE at Rh sites promote the formation of the transition state (Pt-CO···OH-Rh) with a low activation barrier for CO removal. This work provides new insights into the role of OH binding strength in the removal of CO species, which is beneficial for the rational design of highly efficient catalysts.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract It is a grand challenge to deep understanding of and precise control over functional sites for the rational design of highly efficient catalysts for methanol electrooxidation. Here, an L1 2 ...‐Pt 2 RhFe intermetallic catalyst with integrated functional components is demonstrated, which exhibits exceptional CO tolerance. The Pt 2 RhFe/C achieves a superior mass activity of 6.43 A mg Pt −1 , which is 2.23‐fold and 3.53‐fold higher than those of PtRu/C and Pt/C. Impressively, the Pt 2 RhFe/C exhibits a significant enhancement in durability owing to its high CO‐tolerance and stability. Density functional theory calculations reveal that high performance of Pt 2 RhFe intermetallic catalyst arises from the synergistic effect: the strong OH binding energy (OHBE) at Fe sites induce stably adsorbed OH species and thus facilitate the dehydrogenation step of methanol via rapid hydrogen transfer, while moderate OHBE at Rh sites promote the formation of the transition state (Pt‐CO···OH‐Rh) with a low activation barrier for CO removal. This work provides new insights into the role of OH binding strength in the removal of CO species, which is beneficial for the rational design of highly efficient catalysts.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
In this work, a novel cellulose aerogel (CNC-PVAm/rGO) was fabricated using cellulose nanocrystalline (CNC) modified with polyvinylamine (PVAm) and reduced graphene oxide (rGO). The resultant ...CNC-PVAm/rGO was then applied for the adsorption of diclofenac sodium (DCF), a typical non-steroidal anti-inflammatory drug. Characterization using ultra-high-resolution field emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and the Brunauer-Emmett-Teller surface area revealed that the obtained CNC-PVAm/rGO displayed an evident 3D porous structure, which had an ultralight weight, good recovery, abundant surface functional groups (e.g., –NH2 and –OH), and rGO nanosheets. In addition, the material presented a stable crystal structure and large specific surface area (105.73 m2 g−1). During the adsorption of DCF, the CNC-PVAm/rGO aerogel showed a rather excellent adsorption performance, with a maximum adsorption capacity (qmax) of 605.87 mg g−1, which was approximately 53 times larger than that of the bare CNC aerogel (11.45 mg g−1). The adsorption performance of CNC-PVAm/rGO was also better than that of other reported adsorbents. The adsorption of DCF to CNC-PVAm/rGO obeyed the Langmuir isotherm and pseudo-second-order kinetic models, and underwent a spontaneous exothermic process. Moreover, DCF was easily desorbed from CNC-PVAm/rGO with sodium hydroxide solution (0.1 mol L−1), and the absorbent could be reused four times. The introduction of PVAm and rGO to the CNC-PVAm/rGO aerogel also greatly enhanced electrostatic interactions, π-π interactions, and hydrophobic effects. These enhancements significantly promoted the hydrogen bonding interactions between the DCF molecules and CNC-PVAm/rGO, thus resulting in a large improvement in the adsorption performance of the aerogel.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•We have elucidated the pivotal role of OH* as a guiding agent during the MOR process.•Our study offers a rational design for Pt-Cu alloy electrocatalysts, showcasing their superior ...performance.•We provide a deeper understanding of the reaction mechanism, mass-transfer routes of OH*, CH3OH adsorption, intermediate transformation pathways, and the rate-determining step (RDS) in MOR.
The oxidation reaction of methanol (MOR) involves complex intermediate processes, making it difficult to pinpoint the key steps controlling the reaction rate. Although current mechanistic studies encompass various aspects of the MOR process, the lack of an overall consideration of the entire MOR process hinders the effective guidance of catalyst design. In this regard, based on the functional reaction mechanism between OH* and carbon intermediates, we have discovered that OH* as a guiding agent track the oxidation of methanol on the catalyst surface during the MOR process in the alkaline environment. Inspired by the perspective, we rationally design the electrocatalyst (Pt-Cu alloy). Experimental result and density functional theory (DFT) validation revealed that Pt-Cu alloy had strong capabilities for carbon intermediate conversion, meanwhile it possessed lower OH* coverage within a wider potential range. This work makes the MOR process more concrete and coherent transport-conversion mechanism in front of researchers.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The corrosion resistance and biocompatibility of a novel Fe
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Cr
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Mo
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C
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Si
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metallic glass (Fe–MG), are studied by electrochemical measurements and indirect contacting cytotoxicity assays ...for biomedical applications. In Hank’s solution, the Fe–MG shows better corrosion resistance than SS316L, evidenced by the larger polarization resistance in the potentiodynamic and electrochemical impedance spectroscopy (EIS) tests, and the lower amounts of released metallic ions during the immersion test. X-ray photoelectron spectroscopy (XPS) analyses show that a double-layer passive film, consisting of outer Fe-rich oxide and inner Cr-rich oxide, is formed on the Fe–MG. The stable passive film, together with the defect-free nature of the metallic glass, accounts for good corrosion resistance. In addition, in vitro tests suggest that the Fe–MG extracts have good blood compatibility, and no cytotoxicity to murine fibroblast cells. Compared with other Fe-based metallic glasses, the prepared novel Fe–MG contains no toxic elements, and shows a low corrosion rate.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Highlights
A comprehensive summary of the representative promising applications of metal halide perovskite materials, including traditional optoelectronic devices (solar cells, light-emitting diodes, ...photodetectors, lasers), and cutting-edge technologies in terms of neuromorphic devices (artificial synapses and memristors) and pressure-induced emission.
For each application, the fundamentals of the field, the current progress and the remaining challenges are provided, based on the up-to-date works.
Nowadays, the soar of photovoltaic performance of perovskite solar cells has set off a fever in the study of metal halide perovskite materials. The excellent optoelectronic properties and defect tolerance feature allow metal halide perovskite to be employed in a wide variety of applications. This article provides a holistic review over the current progress and future prospects of metal halide perovskite materials in representative promising applications, including traditional optoelectronic devices (solar cells, light-emitting diodes, photodetectors, lasers), and cutting-edge technologies in terms of neuromorphic devices (artificial synapses and memristors) and pressure-induced emission. This review highlights the fundamentals, the current progress and the remaining challenges for each application, aiming to provide a comprehensive overview of the development status and a navigation of future research for metal halide perovskite materials and devices.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
