Utilities are continuously investigating methods to economically reinforce their overhead line (OHL) networks by reconductoring with larger conductors or with novel high-temperature low-sag (HTLS) ...conductor technologies. To further optimise the OHL design, conductor creep ageing is calculated and mitigated at installation, which economically improves an OHLs’ performance. An already established methodology is used to investigate common and HTLS conductors ageing effect on sag and tension in order to highlight the benefits and risks that could result from existing creep mitigation methods particularly on HTLS conductors. The study aims to identify the impact of important design factors such as ice loading and emergency operation events and their frequency of occurrence on creep mitigation as well as to highlight the creep variation of the same materials used particularly on different HTLS conductors. The analysis presented here indicates that pre-tensioning could be more beneficial on soft aluminium HTLS conductors while over-tensioning can result in extensive durations of conductor over-stressing on steel supported and Gap-type conductors. Furthermore, the conductor technology majorly affects the creep of steel core which cannot be considered always as zero. The accuracy of the methodology is also re-validated using recent experimental data from Gap conductor.
The discovery of magnetism in 2D materials offers new opportunities for exploring novel quantum states and developing spintronic devices. In this work, using field‐effect transistors with solid ion ...conductors as the gate dielectric (SIC‐FETs), we have observed a significant enhancement of ferromagnetism associated with magnetic easy‐axis switching in few‐layered Cr2Ge2Te6. The easy axis of the magnetization, inferred from the anisotropic magnetoresistance, can be uniformly tuned from the out‐of‐plane direction to an in‐plane direction by electric field in the few‐layered Cr2Ge2Te6. Additionally, the Curie temperature, obtained from both the Hall resistance and magnetoresistance measurements, increases from 65 to 180 K in the few‐layered sample by electric gating. Moreover, the surface of the sample is fully exposed in the SIC‐FET device configuration, making further heterostructure‐engineering possible. This work offers an excellent platform for realizing electrically controlled quantum phenomena in a single device.
In field‐effect transistors with solid ionic conductors as the gate dielectric, the easy‐axis of the ferromagnetism of Cr2Ge2Te6 thin flakes can be uniformly tuned from the out‐of‐plane direction to the in‐plane direction by an electric field, coinciding with a significant increase of the Curie temperature. The surface of the sample is fully exposed in this type of devices, making further heterostructure‐engineering possible.
A solenoid mock-up called MACQU was designed and tested at CEA Saclay to study the quench propagation in a MADMAX like conductor, i.e. a cable-in-conduit conductor (CICC) with copper conduit cooled ...at 1.8 K with stagnant superfluid helium. Compared with classic CICCs for fusion magnets, the presence of a cable wrapped by a copper tape and inserted in a copper conduit represented new features from the manufacturing point of view that required a R&D program. In this paper the whole process that led to the final conductor designed for the solenoid MACQU, from strand characterization to the fabrication through the R&D and acceptance phases is described.
Conventional stretchable electronics that adopt a wavy design, a neutral mechanical plane, and conformal contact between abiotic and biotic interfaces have exhibited diverse skin‐interfaced ...applications. Despite such remarkable progress, the evolution of intelligent skin prosthetics is challenged by the absence of the monolithic integration of neuromorphic constituents into individual sensing and actuating components. Herein, a bioinspired stretchable sensory‐neuromorphic system, comprising an artificial mechanoreceptor, artificial synapse, and epidermal photonic actuator is demonstrated; these three biomimetic functionalities correspond to a stretchable capacitive pressure sensor, a resistive random‐access memory, and a quantum dot light‐emitting diode, respectively. This system features a rigid‐island structure interconnected with a sinter‐free printable conductor, which is optimized by controlling the evaporation rate of solvent (≈160% stretchability and ≈18 550 S cm−1 conductivity). Devised design improves both areal density and structural reliability while avoiding the thermal degradation of heat‐sensitive stretchable electronic components. Moreover, even in the skin deformation range, the system accurately recognizes various patterned stimuli via an artificial neural network with training/inferencing functions. Therefore, the new bioinspired system is expected to be an important step toward implementing intelligent wearable electronics.
A novel form of stretchable integrated system, namely a bioinspired stretchable sensory‐neuromorphic system, is presented, which comprises an artificial mechanoreceptor, an artificial synapse, and an epidermal photonic actuator as three devices. This system features a bioinspired sensory‐neuromorphic system entailing tactile sensing, pattern learning/inferencing, and visualizing feedback information.
•Reducing the operating temperatures of SOFCs leads to a reduction in power density.•Selection of suitable cathode materials helps to lower the polarization resistance.•MIEC is a promising cathode ...for traditional oxide-conducting O-SOFC.•THOEC shows better performance in proton-conducting H-SOFC environment.
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Solid oxide fuel cells (SOFCs) are energy conversion technologies known for their excellent efficiency and high energy density. However, the application of SOFCs is restrained by their high operating temperatures (800–1000 °C), which result in overall energy system degradation. Reducing the operating temperatures of SOFCs leads to a reduction in power density because of insufficient protonic–ionic conduction. Ionic conduction at the cathode component is related to polarization and area-specific resistance that varies following the selected material. To date, several types of cathode materials have been investigated, namely, pure electronic conductor, mixed protonic–electronic conductor, mixed ionic–electronic conductor (MIEC) and triple protonic–electronic–ionic conductor (THOEC). Amongst these conductors, MIEC and THOEC currently lead in research development and application in conventional and proton-conducting intermediate–low-temperature SOFCs, yet further studies need to be carried out to ensure the continuous improvement of these materials as SOFC cathode. In this review, an explanation on the different types of cathodes will be discussed, with emphasis on MIEC- and THOEC-based cathodes. This review also includes recent progress and challenges encountered for both materials in the SOFC environment.
Despite the breakthrough of over 22% power conversion efficiency demonstrated in organic–inorganic hybrid perovskite solar cells (PVSCs), critical concerns pertaining to the instability and toxicity ...still remain that may potentially hinder their commercialization. In this study, a new chemical approach using environmentally friendly strontium chloride (SrCl2) as a precursor for perovskite preparation is demonstrated to result in enhanced device performance and stability of the derived hole‐conductor‐free printable mesoscopic PVSCs. The CH3NH3PbI3 perovskite is chemically modified by introducing SrCl2 in the precursor solution. The results from structural, elemental, and morphological analyses show that the incorporation of SrCl2 affords the formation of CH3NH3PbI3(SrCl2)x perovskites endowed with lower defect concentration and better pore filling in the derived mesoscopic PVSCs. The optimized compositional CH3NH3PbI3(SrCl2)0.1 perovskite can substantially enhance the photovoltaic performance of the derived hole‐conductor‐free device to 15.9%, outperforming the value (13.0%) of the pristine CH3NH3PbI3 device. More importantly, the stability of the device in ambient air under illumination is also improved.
A new compositional perovskite, CH3NH3PbI3(SrCl2)0.1 with more compact morphology and lower defect concentration is presented. Consequently, a power conversion efficiency of 15.9% with enhanced stability is achieved by employing the structure of hole‐conductor‐free fully printable mesoscopic perovskite solar cell.
We realize superconductor–insulator transitions (SIT) in mechanically exfoliated Bi2Sr2CaCu2O8+δ (BSCCO) flakes and address simultaneously their transport properties as well as the evolution of ...density of states. Back-gating via the solid ion conductor (SIC) engenders a SIT in BSCCO due to the modulation of carrier density by intercalated lithium ions. Scaling analysis indicates that the SIT follows the theoretical description of a two-dimensional quantum phase transition (2D-QPT). We further carry out tunneling spectroscopy in graphite(G)/BSCCO heterojunctions. We observe V-shaped gaps in the critical regime of the SIT. The density of states in BSCCO gets symmetrically suppressed by further going into the insulating regime. Our technique of combining solid state gating with tunneling spectroscopy can be easily applied to the study of other two-dimensional materials.
Overhead lines are used to transmit electricity from where it is generated to the receiving stations. The correct design of an overhead line affects public safety, because it should ensure the ...required clearances between conductors and the ground and objects located in the space under the overhead line. The temperature of conductors in overhead lines depends on the load current and weather conditions, and affects the sag and tension of the conductors. Calculations of sags and tensions of overhead conductors can be performed using simplified calculation methods that do not consider insulator sets. In some situations, this approach may cause calculation errors. This article discusses algorithms for calculating overhead conductor tensions and sags in the tensioning sections of high-voltage overhead lines, accounting for and excluding insulator sets. The analysis is carried out for different lengths of tensioning sections and various thermal and mechanical states of the conductors.
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