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Seabed unexploded ordnance that resulted partly from the high failure rate among munitions from more than 80 years ago and from decades of military training and testing of weapons systems poses an increasing concern all around the world. Although existing magnetic systems can detect clusters of debris, they are not able to tell whether a munition is still intact requiring special removal (e.g. in situ detonation) or is harmless scrap metal. The marine environment poses unique challenges, and transferring knowledge and approaches from land to a marine environment has not been easy and straightforward. On land, the background soil conductivity is much lower than the conductivity of the unexploded ordnance and the electromagnetic response of a target is essentially the same as that in free space. For those frequencies required for target characterization in the marine environment, the seawater response must be accounted for and removed from the measurements. The system developed for this study uses fields from three orthogonal transmitters to illuminate the target and four three-component receivers to measure the signal arranged in a configuration that inherently cancels the system's response due to the enclosing seawater, the sea–bottom interface and the air–sea interface for shallow deployments. The system was tested as a cued system on land and underwater in San Francisco Bay – it was mounted on a simple platform on top of a support structure that extended 1 m below and allowed the diver to place metal objects to a specific location even in low-visibility conditions. The measurements were stable and repeatable. Furthermore, target responses estimated from marine measurements matched those from land acquisition, confirming that the seawater and air–sea interface responses were removed successfully. Thirty-six channels of normalized induction responses were used for the classification, which was done by estimating the target principal dipole polarizabilities. Our results demonstrated that the system can resolve the intrinsic polarizabilities of the target, with clear distinctions between those of symmetric intact unexploded ordnance and irregular scrap metal. The prototype system was able to classify an object based on its size, shape and metal content and correctly estimate its location and orientation.

FeNi3@MnO2/FeNi3 (FMF) nanocomposite with different weight ratios of FeNi3 to FeNi3@MnO2 was prepared under 100 ℃ for 3 h. Then, these compounds’ structural and microstructural properties were characterized using X-ray diffraction, field emission scanning electron microscopy, and transmission electron microscopy. Also, the electromagnetic properties of the samples were characterized using a vibrating sample magnetometer, and microwave absorption in the 2–18 GHz frequency range. The results show that the magnetic characteristics of the samples increased with the increase in the ratio of FeNi3 nanoparticles. However, the excessive growth of FeNi3 nanoparticles decreased the dielectric properties (the dielectric constant) so that the electrical conductivity of the FMF (4) sample is lower than the FMF (3) sample. The reflection loss of the FMF (1) sample was better than the other samples and about − 27 db. [ABSTRACT FROM AUTHOR]

FeNi3@MnO2/FeNi3 (FMF) nanocomposite with different weight ratios of FeNi3 to FeNi3@MnO2 was prepared under 100 ℃ for 3 h. Then, these compounds’ structural and microstructural properties were characterized using X-ray diffraction, field emission scanning electron microscopy, and transmission electron microscopy. Also, the electromagnetic properties of the samples were characterized using a vibrating sample magnetometer, and microwave absorption in the 2–18 GHz frequency range. The results show that the magnetic characteristics of the samples increased with the increase in the ratio of FeNi3 nanoparticles. However, the excessive growth of FeNi3 nanoparticles decreased the dielectric properties (the dielectric constant) so that the electrical conductivity of the FMF (4) sample is lower than the FMF (3) sample. The reflection loss of the FMF (1) sample was better than the other samples and about − 27 db. [ABSTRACT FROM AUTHOR]

As an effective geophysical tool, ground penetrating radar (GPR) is widely used for environmental and engineering detections. Numerous numerical simulation algorithms have been developed to improve the computational efficiency of GPR simulations, enabling the modeling of complex structures. The discontinuous Galerkin method is a high efficiency numerical simulation algorithm which can deal with complex geometry. This method uses numerical fluxes to ensure the continuity between elements, allowing Maxwell's equations to be solved within each element without the need to assemble a global matrix or solve large systems of linear equations. As a result, memory consumption can be significantly reduced, and parallel solvers can be applied at the element level, facilitating the construction of high-order schemes to enhance computational accuracy. In this paper, we apply the discontinuous Galerkin (DG) method based on unstructured meshes to 3D GPR simulation. To verify the accuracy of our algorithm, we simulate a full-space vacuum and a cuboid in a homogeneous medium and compare results, respectively, with the analytical solutions and those from the finite-difference method. The results demonstrate that, for the same error level, the proposed DG method has significant advantages over the FDTD method, with less than 20% of the memory consumption and calculation time. Additionally, we evaluate the effectiveness of our method by simulating targets in an undulating subsurface, and further demonstrate its capability for simulating complex models. [ABSTRACT FROM AUTHOR]

The conventional total-field/scatter-field (TF/SF) technique is commonly used in electromagnetic scattering simulations, but it has a limitation in that it confines the scatterer within the TF/SF boundary, and thus cannot be employed directly in simulations of infinite rough surfaces. Introducing incident waves accurately and effectively becomes a challenge for the finite-difference time-domain method when dealing with rough surfaces. To address this issue, this paper extends a generalized total-field/scattered-field (G-TF/SF) method that embeds the TF/SF boundary within the convolutional perfectly matched layer to handle three-dimensional (3-D) electromagnetic scattering from rough surfaces. The numerical results demonstrate that the G-TF/SF technique can effectively eliminate the edge effect caused by ground truncation. Moreover, the accuracy of the G-TF/SF method is verified by comparing its simulation results for the flat ground with the theoretical solution. Finally, the G-TF/SF technique is applied to simulate the electromagnetic environment for rough surfaces. [ABSTRACT FROM AUTHOR]

A comprehensive framework for designing a micro-nuclear magnetic resonance (NMR) front-end is presented. Key radio frequency (RF) engineering principles are established to enable efficient excitation and detection of NMR signals. This foundation aims to guide the optimal design of novel handheld NMR devices operating with magnetic fields ( B 0 ) below 0.5 Tesla and RF frequencies under 30 MHz. To address the complexities of signal-to-noise ratio optimization in this regime, a specialized metric called the coil performance factor (CPF) is introduced, emphasizing the role of coil design. Through systematic optimization under realistic constraints, an optimal coil configuration maximizing the CPF is identified. This design, with three turns, a coil width of 0.22 mm, and a coil spacing of 0.15 mm, achieves an optimal balance between magnetic field strength, homogeneity, and noise. This work serves as a valuable resource for engineers developing optimized coil designs and RF solutions for handheld NMR devices, providing clear explanations of essential concepts and a practical design methodology. [ABSTRACT FROM AUTHOR]

Purpose: Due to the priority of small damping, magnetic rolling pendulum (MRP) system has been utilized in the area of energy harvesting, and numerous studies focused on the broadband response characteristic and practical applications of the harvesters. By combining the magnetic force and gravity of the rolling magnet, bistable configurations can be achieved, and the complex nonlinear dynamics under parametric excitation remain an open issue. Therefore, this paper investigate the complex dynamic behaviors of a gravity-induced bistable MRP harvester under parametric excitation. Methods: By establishing the dynamic model, the outcomes of the harvester are predicted through electromagnetic induction and finite element analysis. Under sweep and constant frequency excitation, numerical simulations are undertaken to study the dynamics of the system. In addition, the multiple solution characteristics are considered through the basins of attraction. Results: Under sweep frequency excitation with a level of 0.3 g, the system could oscillate across the potential barrier over a wide range of low frequencies from 4.36 Hz to 14.13 Hz. Regarding the constant frequency excitations, bifurcation diagrams, and cloud maps of mean square voltage and 0–1 test demonstrate that the system exhibits complex dynamic behaviors including multiple patterns of interwell and intrawell oscillations, and these can be identified by the means of phase orbit, Poincaré map, multiscale entropy, and reconstructed phase-space. Additionally, the multi-solution phenomena of the system reveal that the number of solutions is closely related to the excitation amplitude and frequency. Conclusion: In general, this study offers a novel strategy for realizing multistable oscillation, and the optimization and experimental verification of the harvester for enabling low-power consumption devices will be considered in future studies. [ABSTRACT FROM AUTHOR]

Featured Application: Magnetic FEM analysis results for quasi-static cases can be used in dynamic simulations through Look-Up Tables, which reduce the computation time. This study presents the design and analysis of a proportional solenoid used in electro-pneumatic brake systems for heavy vehicles. The solenoid was designed using a traditional method, and its static and dynamic characteristics were investigated both theoretically and experimentally. ANSYS 2024 R1 Maxwell was employed for theoretical static analysis, focusing on the effects of the geometric dimension parameters in the fixed and moving pole contact regions on the force–displacement characteristics. The optimal dimensions for proportionality were determined under constraint parameters. The static analysis results provided the magnetization curve data, which were used to create Look-Up Tables for a dynamic model in MATLAB R2024b-Simulink, and this method reduced the simulation time and increased the dynamic simulation accuracy. Following static analysis, a prototype electromagnet was manufactured and tested. The solenoid achieved a constant magnetic force of 45 ± 3 N with a current of 1.3 A over a working range of 1–3 mm. The dynamic model, incorporating data from ANSYS, yielded results that closely matched the experimental findings. [ABSTRACT FROM AUTHOR]

Grid-integrated photovoltaic (PV) systems are currently undergoing explosive growth in Malaysia. However, as more PV systems are installed close to transmission lines, there are concerns about the impact of electromagnetic (EM) properties affecting the performance and operation of the PV systems if they are exposed to lightning strikes, particularly indirect ones. Therefore, this study aims to model the impact of indirect lightning strikes on PV systems installed in proximity to transmission lines. The model involves developing a 3D model of the PV system together with a sample transmission line and creating an artificial lightning event to study the EM activity within the area. The results are compared to the IEC 61000 standard to determine its level of r\hazard. From the simulation results, it was found that the current intensity, H, of the disturbance, can reach up to 63% more than the standard limit stipulated in the standards. The significance of the study ensures that PV systems installed within the vicinity of power lines or substations have adequate lightning protection systems (LPS) as well as proper earthing systems. [ABSTRACT FROM AUTHOR]

Electromagnetic pulse welding (EMPW) is commonly used for welding copper and aluminum alloy. The welding gap is important in the EMPW process. The research focused on the effect of welding gap on the welding process and the mechanical property of joints. During the EMPW experiments, the deformation, collision, and metal jet were recorded with a high-speed camera. The joint mechanical property was tested. SEM and EDS were employed to examine the bonding interface. Results indicated that the welding gap length did not significantly influence the aluminum alloy plate motion behavior when it was long enough. With the welding gap width increasing, the collision velocity initially increased and subsequently decreased, and the angle between the two plates when they first collided increased continuously. The intensity and duration of the metal jet and the joint mechanical properties also increased first and then decreased. The welding marks widened first and then narrowed. [ABSTRACT FROM AUTHOR]

Energy harvesting technology plays an important role in converting ambient energy into useful electrical energy to power wireless sensing and system monitoring, especially for systems operating in isolated, abandoned or embedded locations where battery replacement or recharging is not a feasible solution. This paper provides an integrative study of the methodologies and technologies of energy harvesting from fluid flow-induced vibration (FIV). The recent research endeavors contributing to flow-based energy harvesting have been reviewed to present the state-of-the-art issues and challenges. Several mechanisms on FIVs including vortex-induced vibrations (VIVs), flutter, galloping and wake galloping are thoroughly discussed in terms of device architecture, operating principles, energy transduction, voltage production and power generation. Additionally, advantages and disadvantages of each FIV energy harvesting mechanism are also talked about. Power enhancement methods, such as induced nonlinearities, optimized harvester's configuration, hybridization and coupling of aerodynamic instabilities, for boosting the harvester's output are also elucidated and categorized. Moreover, rotary wind energy harvesters are reviewed and discussed. Finally, the challenges and potential directions related to the flow-based energy harvesters (FBEHs) are also mentioned to provide an insight to researchers on the development of sustainable energy solutions for remote wireless sensing and monitoring systems. [ABSTRACT FROM AUTHOR]

In response to the challenges posed by the complexity and potential hazards of traditional chemical methods for detecting the surface density of carbon fiber prepreg materials, this paper explores the use of eddy current testing principles. It establishes the relationship between coil impedance variation and the surface density of carbon fiber prepreg materials and designs a quadrupolar excitation eddy current detection probe. This probe can detect the surface density of both single-line and woven carbon fiber prepreg structures. The overall structure and dimensions of the designed quadrupolar probe were optimized using finite element simulation software. The results show that the number of coil turns significantly affects the sensor performance, with more turns leading to increased sensitivity. Moreover, with the same number of coil turns, smaller inner diameters and larger outer diameters of the coil enhance sensor sensitivity. A comprehensive comparison between unidirectional and woven carbon fiber models suggests that woven structures have superior electrical conductivity at identical excitation frequencies, while unidirectional models show more pronounced electrical anisotropy. These findings provide valuable insights for analyzing electrical properties, numerical simulations, and eddy current testing in composite materials. [ABSTRACT FROM AUTHOR]

In this paper wide angle wide band polarization insensitive Metamaterial absorber (MA) has been proposed. The proposed unit cell structure consists of hexagonal concentric ring along with hexagonal packing. The structure is fabricated on FR4 substrate. The advantage of hexagonal packing is that it covers less area as compared to square packing. The unit cell structure is scaled w.r.t hexagonal ring and resistance of the substrate. The absorptivity achieved range from 6.54 to 14.85 GHz having Bandwidth (BW) of 8.31 GHz. The metamaterial behaviour of the structure is proven by plotting real and imaginary pat of permittivity and permeability. Absorption mechanism is shown by plotting surface current distribution at the top and bottom of the surface. The proposed MA structure is analysed for normal and oblique incidence. From the normal incidence it was found that structure has wide angle polarization insensitive. The absorptivity of the fabricated structure is measured inside the anechoic chamber. The simulated and measured plot is compared and found that both the results are very close to each other. At last, the proposed and already reported MAs are compared and from the observation it was found that proposed unit cell have larger BW compact in size, polarization insensitive and have hexagonal packing. The proposed MA covers partial C band, full X band and partial Ku band. The Proposed MA found practical applications for satellite communication, Wi-Fi devices, cordless telephone, military, air traffic control, defence tracking, vehicle speed detection. [ABSTRACT FROM AUTHOR]

Aims: Electromagnetic induction heating has demonstrated in vitro antibacterial efficacy over biofilms on metallic biomaterials, although no in vivo studies have been published. Assessment of side effects, including thermal necrosis of adjacent tissue, would determine transferability into clinical practice. Our goal was to assess bone necrosis and antibacterial efficacy of induction heating on biofilm-infected implants in an in vivo setting. Methods: Titanium-aluminium-vanadium (Ti6Al4V) screws were implanted in medial condyle of New Zealand giant rabbit knee. Study intervention consisted of induction heating of the screw head up to 70°C for 3.5 minutes after implantation using a portable device. Both knees were implanted, and induction heating was applied unilaterally keeping contralateral knee as paired control. Sterile screws were implanted in six rabbits, while the other six received screws coated with Staphylococcus aureus biofilm. Sacrifice and sample collection were performed 24, 48, or 96 hours postoperatively. Retrieved screws were sonicated, and adhered bacteria were estimated via drop-plate. Width of bone necrosis in retrieved femora was assessed through microscopic examination. Analysis was performed using non-parametric tests with significance fixed at p ≤ 0.05. Results: The width of necrosis margin in induction heating-treated knees ranged from 0 to 650 μm in the sterile-screw group, and 0 to 517 μm in the biofilm-infected group. No significant differences were found between paired knees. In rabbits implanted with sterile screws, no bacteria were detected. In rabbits implanted with infected screws, a significant bacterial load reduction with median 0.75 Log10 colony-forming units/ml was observed (p = 0.016). Conclusion: Induction heating was not associated with any demonstrable thermal bone necrosis in our rabbit knee model, and might reduce bacterial load in S. aureus biofilms on Ti6Al4V implants. Cite this article: Bone Joint Res 2024;13(12):695–702.

Carbon fiber laminates enjoy a wide range of applications from innovative architectural design to aerospace and the safety overwrap for pressure vessels. In the case of carbon fiber overwrapped pressure vessels (COPVs), the overwrap thickness can vary from 6 mm (∼ 0.25 inch) for thin-walled COPV up to 25 mm (∼ 1”) or more for thick walled COPV, depending on the vessel type. The failure mechanisms for carbon fiber are more complex than for metals and monitoring COPVs for defects or fatigue over their lifetime is further complicated by the thickness of the carbon fiber used. Traditional electromagnetic NDE methods, such as eddy current testing (ECT) for imaging defects in these structures has been severely limited, achieving accurate identification to about 4 mm in depth. In this paper, a new technique is introduced to address these shortcomings, Electro-Magnetic-Inductive-Coupling-Analysis, or EMICA, can be used to detect damage inside thick carbon fiber laminate pieces. EMICA is based on the interaction of the repeating three-dimensional structure of carbon fiber and low-frequency electromagnetic waves that are allowed to actively spread through the conductive bulk composite material highlighting defects such as delamination and fiber disruptions, well below the laminate surface. In this paper, EMICA is demonstrated in flat carbon fiber laminates up to ∼ 12 mm (0.5”) thick, made in-house, with known defects hidden through the thickness of the piece that cannot be detected via visual inspection. Delaminations, cuts/cracks, and the underlying ply layup structure can all be identified in the EMICA images. It is shown that three imbedded PTFE delaminations at varying depths (3 mm, 6 mm, 9 mm) are simultaneously imaged using EMICA in a ½” thick CF laminate [0°/90°] panel with an excitation frequency of 40 kHz. Furthermore, the electromagnetic focal point can be chosen within the depth of CF composites by intelligently selecting the excitation frequency for the ply layup being probed, while the traditional penetration depth equation does not hold true in these complex structures. [ABSTRACT FROM AUTHOR]

Micro-electro-discharge drilling (μ EDD) is a type of non-traditional machining process used for drilling micro-holes of desired dimensions with a high aspect ratio. But, there are no such research works that could have explained the desired accurate circular shape of micro-holes. The need for a more advanced hybrid machining process to improve the overall efficiency in terms of mainly desired circular shape and radial overcut is evolved. In this research work, an electromagnetic field force-assisted micro-EDM process has been carried out on Inconel 800 with a copper tool of 450 μ m. Experimental results showed that measured metal removal rate and tool wear rate decreased for ascending values of magnetic flux density, peak current and gap voltage, whereas circularity increases linearly with an increase in magnetic flux density and also the effects of magnetic field on circularity of micro-holes on Inconel 800 are more predominant than other parameters. [ABSTRACT FROM AUTHOR]

This paper introduces a new mathematical modeling of a thermoelastic and electromagnetic infinite body with a cylindrical cavity in the context of four different thermoelastic theorems; Green–Naghdi type-I, type-III, Lord–Shulman, and Moore–Gibson–Thompson. Due to the convergence of the four theories under study and the simplicity of putting them in a unified equation that includes these theories, the theories were studied together. The bunding plane of the cavity surface is subjected to ramp-type heat and is connected to a rigid foundation to stop the displacement. The novelty of this work is considering Maxwell's time-fractional equations under the Caputo fractional derivative definition. Laplace transform techniques were utilized to obtain solutions by using a direct approach. The Laplace transform's inversions were calculated using Tzou's iteration method. The temperature increment, strain, displacement, stress, induced electric field, and induced magnetic field distributions were obtained numerically and represented in figures. The time-fractional parameter of Maxwell's equations has a significant impact on all the mechanical studied functions and does not affect the thermal function. The time-fractional parameter of Maxwell's equations works as a resistance to deformation, displacement, stress, and induced magnetic field distributions, while it acts as a catalyst to the induced electric field through the material. [ABSTRACT FROM AUTHOR]

ABSTRACT Background Aim Methods Results Conclusion Energy‐based photoelectric and ultrasonic devices are essential for skin rejuvenation and resurfacing in the field of plastic surgery and dermatology. Both functionality and appearance are impacted by factors that cause skin to age, and various energy types have variable skin penetration depths and modes of transmission.The objective is to advise safe and efficient antiaging treatment while precisely and sensitively controlling and assessing the extent of thermal damage to tissues caused by different kinds of energy‐based devices.A literature search was conducted on PubMed to review the mechanisms of action and thermal effects of photoelectric and ultrasonic devices in skin remodeling applications.This paper reviews the thermal effects of energy‐based devices in skin resurfacing applications, including the tissue level and molecular biochemical level. It seeks to summarize the distribution form, depth of action, and influencing factors of thermal effects in combination with the mechanisms of action of various types of devices.Accurate control of thermal damage is crucial for safe and effective skin remodeling treatments. Thorough investigation of molecular biochemical indicators and signaling pathways is needed for real‐time monitoring and prevention of severe thermal injury. Ongoing research and technological advancements will improve the accuracy and control of thermal damage during treatments. [ABSTRACT FROM AUTHOR]

This work presents the development of a magnetic levitation system with a ferrite core, designed for electromagnetic energy harvesting from mechanical vibrations. The system consists of a fixed enamel-coated copper coil and five neodymium-iron-boron permanent magnets housed within a PVC spool. To enhance magnetic flux concentration, a manganese-zinc ferrite (Mn-Zn) ring was employed within the spool. Experimental tests were conducted at frequencies up to 20 Hz, demonstrating the device's potential for harvesting energy from small vibrations, such as those generated by human biomechanical movements, achieving operating voltages up to 3 V. Additionally, the architecture is scalable for larger systems and allows for the integration of multiple transducers without magnetic field interference, independent of the frequency or excitation phase of each transducer. [ABSTRACT FROM AUTHOR]

Highlights To achieve the wave‐transparent and anti/de‐icing requirements of electromagnetic functional structural components on the windward surface of the aircraft, the PTFE capillary hot air tubes were pre‐buried inside the quartz fiber cloth and the hot air anti/de‐icing quartz fiber/PTFE capillary/epoxy resin (QF/PTFE/EP) composite components was prepared to that met the wave‐transparent performance. A multi‐field coupled numerical finite element simulation model was established, and the anti/de‐icing performance of the QF/PTFE/EP composite with different built‐in tube diameters were investigated by combining experiments and simulations under different hot air temperatures and pressures. The feasibility of hot air anti/de‐icing was verified through anti/de‐icing experiments and numerical simulation. The electromagnetic transmittance of the prepared hot air anti/de‐icing QF/PTFE/EP composite components was tested to characterize the effect on the stealth performance of the aircraft under the service environment. The experimental results demonstrated that with 5 mm tube pitch and hot air of 60°C ± 1°C, the surface temperature of the component with three tube diameters could reach more than 10°C. Furthermore, the decrease in the transmittance of the hot air anti/de‐icing QF/PTFE/EP composite components caused by different incidence angles and two polarization modes was less than 3%. The hot air QF/PTFE/EP anti/de‐icing composite components were fabricated. The heat transfer, anti/de‐icing, and electromagnetic transmittance performance of the hot air QF/PTFE/EP anti/de‐icing QF/PTFE/EP components were investigated. The experimental and simulation results verified the hot air anti/de‐icing QF/PTFE/EP components met the requirement of aircraft anti/de‐icing and wave transmission. [ABSTRACT FROM AUTHOR]

This paper introduces a new mathematical modelling method of a thermoelastic and electromagnetic half-space in the context of four different thermoelastic theorems: Green–Naghdi type-I, and type-III; Lord–Shulman; and Moore–Gibson–Thompson. The bunding plane of the half-space surface is subjected to ramp-type heat and traction-free. We consider that Maxwell's time-fractional equations have been under Caputo's fractional derivative definition, which is the novelty of this work. Laplace transform techniques are utilized to obtain solutions using the state-space approach. Laplace transform's inversions were calculated using Tzou's iteration method. The temperature increment, strain, displacement, stress, induced electric field, and induced magnetic field distributions were obtained numerically and are illustrated in figures. The time-fraction parameter of Maxwell's equations had a major impact on all the studied functions. The time-fractional parameter of Maxwell's equations worked as resistant to the changing of temperature, particle movement, and induced magnetic field, while it acted as a catalyst to the induced electric field through the material. Moreover, all the studied functions have different values in the context of the four studied theorems. [ABSTRACT FROM AUTHOR]

All physical phenomena that occur in nature are related to one or another mutual effects. Electric and magnetic phenomena are of particular importance in order to gain extensive knowledge about the structure of the world around us. Electric and magnetic forces can be transmitted over a certain distance like gravitational forces. While the source of the gravitational field is mass, the source of the electromagnetic field is electric charge. The only reason for such a contradiction may be the discrepancy between the research methods used by science and the essence of the problem being studied. Historically, all research methods should be divided into methods before and after the advent of the computer era. It was the former that were at the disposal of researchers whose recommendations were used in the formation of the existing regulatory framework. [ABSTRACT FROM AUTHOR]

Results from clinical trials show that serotonergic psychedelics have efficacy in treating psychiatric disorders, where currently approved pharmacotherapies are inadequate. Developing psychedelic medicines, however, comes with unique challenges, such as tempering heightened anxiety associated with the psychedelic experience. We conceived a new strategy to potentially mitigate psychedelic effects with defined electromagnetic signals (ES). We recorded the electromagnetic fields emitted by the serotonin 2 receptor (5-HT2R) agonist (±)-2,5-dimethoxy-4-iodoamphetamine (DOI) and converted them to a playable WAV file. We then exposed the DOI WAV ES to mice to assess its effects on th DOI-elicited, 5-HT2AR dependent head-twitch response (HTR). The DOI WAV signal significantly attenuated the HTR in mice elicited by 0.1 and 0.3 mg/kg subcutaneous DOI (p < 0.05 and p < 0.01, respectively). A scrambled WAV signal did not affect the DOI-elicited HTR, suggesting specificity of the DOI WAV signal. These results provide evidence that defined ES could modulate the psychoactive effects of serotonergic psychedelics. We discuss putative explanations for the distinct effects of the DOI WAV signal in the context of previous studies that demonstrate ES's efficacy for treating other conditions, including pain and cancer. Plain Language Summary: Numerous clinical studies demonstrate that psychedelic drugs can treat psychiatric disorders. A challenge with psychedelic drugs is that they can elicit distressing experiences, which require psychological support in some patients. Recent developments have allowed for the recording of the electromagnetic shell or field of molecules in solution. These electromagnetic signals (ES) can be emitted (as a magnetic field) to emulate the effects of the recorded drug. By using ES, we have the potential to manage or mitigate the negative effects of a drug, simply by turning off the magnetic field. The main target of serotonergic psychedelic drugs is the serotonin receptor, 5-HT2A. A reliable and well-studied drug used in psychedelic research is (±)-2,5-dimethoxy-4-iodoamphetamine (DOI). DOI binds and activates the 5-HT2A receptor. DOI is known to elicit head twitching in mice (called the head-twitch response or HTR) that is indicative of 5-HT2A receptor activation. A recording of DOI was played to evaluate its effect on the head-twitch response in mice. Here we report that the DOI WAV signal decreased the head-twitch response observed after treating mice with the DOI drug. The effects were measurable, reproducible and demonstrated the ability of the DOI recording to dampen the head-twitch response. This WAV recording has the potential to interfere with the unwanted effects of psychedelics, making their use safer. [ABSTRACT FROM AUTHOR]

A study and performance analysis of magnet positions in different topology on the surface of rotor in permanent magnet synchronous motors (PMSMs) based on finite element method is observed here. A 3-phase interior PMSM is numerically simulated with ANSYS Maxwell 2018.1. Differently positioned permanent magnets improve the performance of PMSMs. Apart from handling nonlinear equations, FEM is used for simulation. ANSYS is used to analyze PMSM performance under variable conditions. This proposal examines a three-phase, 0.55 kW PMSM at 220 V, 50 Hz. Here rotor topologies of five types, namely, (i) spoke/tangential, (ii) saturable bridge / u-shape, (iii) V-shape, (iv) radial, and (v) segmented bridge permanent magnet rotor are taken for observation. The motive of this study is to analyze the performance of PMSMs in different rotor designs with different magnet positions. All topologies have been modeled and simulated with ANSYS. Each topology is compared in terms of electromagnetic and mechanical parameters. The 2D model is used to model the distribution of magnetic fields and the performance of operating parameters under transient and steadystate conditions. Magnetic flux, and efficiency are heavily influenced by the rotor shape with the volume of magnet. A study of radial force distribution and mechanical stress across rotor surface is also discussed. Motor performance is affected by the design of PMs. [ABSTRACT FROM AUTHOR]

Microwave energy will soon be used in material manufacturing. Microwaves may generate a lot of heat. Through many interactions, microwaves convey electromagnetic energy straight to the material's molecules. Direct molecular interaction transfers electromagnetic energy to materials. Microwaves are increasingly used to process materials because to their time and energy economy, shorter process cycle times, enhanced mechanical characteristics, and reduced environmental dangers. Microwave processing transfers linearly equal electric and magnetic energy between molecules. Microwaves can process several materials. Metal matrix composites, fibre reinforced polymers (FRP), alloys, ceramics, metals, pulverised metallurgy, metal coatings, and metal cladding are examples. This article lists basic microwave properties and briefly discusses the mechanisms that regulate microwave-material interactions. The essay also discusses the systems that control interactions. Microwave heating basics have been covered here. Cladding, coating, and glazing are the main uses of microwave energy in surface engineering. [ABSTRACT FROM AUTHOR]

In this paper, we explore the benefits of using a magnetostrictive component in a variable reluctance energy harvester. The intrinsic magnetic field bias and the possibility to utilize magnetic force to achieve pre-stress leads to a synergetic combination between this type of energy harvester and magnetostriction. The proposed energy harvester system, to evaluate the concept, consists of a magnetostrictive cantilever beam with a cubic magnet as proof mass. Galfenol, Fe81.6Ga18.4, is used to implement magnetostriction. Variable reluctance is achieved by fixing the beam parallel to an iron core, with some margin to create an air gap between the tip magnet and core. The mechanical forces of the beam and the magnetic forces lead to a displaced equilibrium position of the beam and thus a pre-stress. Two configurations of the energy harvester were evaluated and compared. The initial configuration uses a simple beam of aluminum substrate and a layer of galfenol with an additional magnet fixing the beam to the core. The modified design reduces the magnetic field bias in the galfenol by replacing approximately half of the length of galfenol with aluminum and adds a layer of soft magnetic material above the galfenol to further reduce the magnetic field bias. The initial system was found to magnetically saturate the galfenol at equilibrium. This provided the opportunity to compare two equivalent systems, with and without a significant magnetostrictive effect on the output voltage. The resonance frequency tuning capability, from modifying the initial distance of the air gap, is shown to be maintained for the modified configuration (140 Hz/mm), while achieving RMS open-circuit coil voltages larger by a factor of two (2.4 V compared to 1.1 V). For a theoretically optimal load, the RMS power was simulated to be 5.1 mW. Given the size of the energy harvester (18.5 cm3) and the excitation acceleration (0.5 g), this results in a performance metric of 1.1 mW/cm3g2. [ABSTRACT FROM AUTHOR]

This paper comprehensively investigates the performance characteristics of a long-stroke electromagnetic double-reel hammer compared to a conventional hammer. Quantitative analysis indicates that the long-stroke hammer shows a significant increase in striker speed and impact energy. The impact energy has increased by 255%, and energy losses in copper windings have decreased by 124% per operating cycle. Additionally, the long-stroke hammer demonstrates a 105% reduction in energy consumption and a 52% improvement in overall efficiency per cycle compared to the conventional hammer. This study examines the operational characteristics of the longstroke hammer throughout its cycle using field theory methods, MATLAB simulations, and experimental tests. Results indicate higher impact energy and speed, lower energy losses in copper windings, and higher efficiency per cycle for the long-stroke hammer. Furthermore, a mathematical model of the long-stroke hammer is developed, incorporating static parameters and oscillograms of striker movement and current flow. A comprehensive comparison of the performance indicators of both hammers reveals significant improvements in lifting height, cycle duration, impact frequency, and striker speed for the long-stroke hammer. Overall, these findings suggest that the long-stroke operating mode can significantly enhance the efficiency and performance of conventional hammers while simultaneously reducing impact frequency and machine heating. [ABSTRACT FROM AUTHOR]

Although much information can be gained about thermally induced microstructural changes in metals through the measurement of their thermophysical properties using a differential scanning calorimeter (DSC), due to competing influences on the signal, not all microstructural changes can be fully characterised this way. For example, accurate characterisation of recrystallisation, tempering, and changes in retained delta ferrite in alloyed steels becomes complex due to additional signal changes due to the Curie point, oxidation, and the rate (and therefore the magnitude) of transformation. However, these types of microstructural changes have been shown to invoke strong magnetic and electromagnetic (EM) responses; therefore, simultaneous EM measurements can provide additional complementary data which can help to emphasise or deconvolute these complex signals and develop a more complete understanding of certain metallurgical phenomena. This paper discusses how a DSC machine has been modified to incorporate an EM sensor consisting of two copper coils printed onto either side of a ceramic substrate, with one coil acting as a transmitter and the other as a receiver. The coil is interfaced with a custom-built data acquisition system, which provides current to the transmit coil, records signals from the receive coil, and is controlled by a graphical user interface which allows the user to select multiple excitation frequencies. The equipment has a useable frequency range of approximately 1–100 kHz and outputs phase and magnitude readings at a rate of approximately 50 samples per second. Simultaneous DSC-EM measurements were performed on a nickel sample up to a temperature of 600 °C, with the reversable ferromagnetic to paramagnetic transition in the nickel sample invoking a clear EM response. The results show that the combined DSC-EM apparatus has the potential to provide a powerful tool for the analysis of thermally induced microstructural changes in metals, feeding into research on steel production, development of magnetic and conductive materials, and many more areas. [ABSTRACT FROM AUTHOR]

Simple, instantaneous, contactless, multiple-point metamaterial-inspired microwave sensors, composed of multi-band, low-profile metamaterial-inspired antennas, were developed to detect and identify meningioma tumors, the most common primary brain tumors. Based on a typical meningioma tumor size of 5–20 mm, a higher operating frequency, where the wavelength is similar or smaller than the tumor target, is crucial. The sensors, designed for the microwave Ku band range (12–18 GHz), where the electromagnetic property values of tumors are available, were implemented in this study. A seven-layered head phantom, including the meningioma tumors, was defined using actual electromagnetic parametric values in the frequency range of interest to mimic the actual human head. The reflection coefficients can be recorded and analyzed instantaneously, reducing high electromagnetic radiation consumption. It has been shown that a single-band detection point is not adequate to classify the nonlinear tumor and head model parameters. On the other hand, dual-band and tri-band metamaterial-inspired antennas, with additional detecting points, create a continuous function solution for the nonlinear problem by adding extra observation points using multiple-band excitation. The point mapping values can be used to enhance the tumor detection capability. Two-point mapping showed a consistent trend between the S11 value order and the tumor size, while three-point mapping can also be used to demonstrate the correlation between the S11 value order and the tumor size. This proposed multi-detection point technique can be applied to a sensor for other nonlinear property targets. Moreover, a set of antennas with different polarizations, orientations, and arrangements in a network could help to obtain the highest sensitivity and accuracy of the whole system. [ABSTRACT FROM AUTHOR]

Increasingly ambitious space missions rely upon the advancement of propulsion systems, and innovations in electric propulsion represent a vital step toward potential solutions. Electric propulsion research has indicated improved thruster performance at higher magnetic fields, but real-world implementations have been encumbered by available magnet technology. In this study, a new class of superconducting magnet designed for such space applications is demonstrated. A central cathode electrostatic thruster was paired with a conduction cooled high temperature superconducting magnet operated in non-pulsed mode. Using Xe propellant, thrust of 38–73 mN was measured at a central bore magnetic field of 1.13 T and on-anode field of 1.28 T, and the thruster's specific impulse was throttled between 1050s and 1450s. The peak thruster efficiency was 18.7%, inclusive of the power consumption of the magnet subsystems. This was performed without the onset of plasma instabilities, and is the first case in the literature of a high temperature superconducting plasma thruster operating at >1 T. [ABSTRACT FROM AUTHOR]

This study investigates wind energy harvesting from electromagnetic dual cantilever flutter (DCF) and multi cantilever flutter (MCF) arrays. Initially, the bare DCF was tested under several wind speeds at four different gap distances to analyse and verify its behaviour. Results suggest that the characteristics of the DCF is ideal for electromagnetic energy harvesting. Two identical sets of wounded coils and magnets were then fixed onto the DCF to generate an induced voltage output from the anti-phase motion. Experimental findings demonstrated a significant power density of 11 × 10−3 mW/cm3 at a wind speed of 18.0 ms−1 when using shorter and thicker beams, which is comparable to previous flutter-based energy harvesters. An additional magnet-holding beam was then added beside the DCF beams to form a multi cantilever flutter (MCF) array of three identical beams. Visual observation confirms that alternate beams in the MCF array also flutter in an anti-phase motion. The power output per beam and power density recorded for the MCF array was 38.0% higher than the DCF harvester due to the increase in functional coil output and magnetic flux density. Finally, further analysis suggest that an odd number of beams is more favourable for electromagnetic MCF array harvesters. [ABSTRACT FROM AUTHOR]

This study investigates the effect of electromagnetic energy implementation in the use of electric, magnetic, and hybrid nanofluids for enhanced oil recovery. The challenge lies in comprehending the intricate interplay of these factors to enhance the recovery factor (RF) of oil. We conducted a comprehensive analysis of parameters influencing oil recovery at its primary, secondary, and tertiary stages using finite-element-based simulations. Transitioning to the secondary stage, we observe a positive correlation between increasing brine flow rates and heightened RF. In the tertiary stage, a comparative assessment of nanofluids, including magnetite (Fe3O4), zinc oxide (ZnO), and copper oxide (CuO), reveals that enhancing nanofluid concentrations up to 0.001 % positively impacts RF, with Fe3O4 leading the pack at 22.20 %, followed by ZnO at 21.00 %, and CuO at 11.02 %. The introduction of electromagnetic field consistently augments RF for all nanofluids by a minimum of 4.8 %. Furthermore, this study explores the effect of hybrid nanofluids on RF, which tend to exhibit lower RF values. However, the introduction of electromagnetic energy significantly enhances RF for all hybrid nanofluids. The study offers valuable insights into the potential of nanomaterials and electromagnetic methods in the oil and gas industry.

A piezoelectric‐electromagnetic composite energy harvester (PECEH) has been designed, to mainly study the relationship between the length and angle of piezoelectric cantilever beams and their power generation performance, and the analysis of dynamic models in magnetic levitation systems and the impact of magnet size on power generation performance. In this device, piezoelectric energy harvester (PEH) and electromagnetic harvester (EMH) are used as powered and sensing, respectively. The PEH collects vibration to generate electricity and supplies energy to the EMH, which then transmits the wireless signal. EMH adopts a magnetic levitation device with higher sensitivity, while PEH uses a direct contact strike piezoelectric plate to increase power generation. The paddles are made of flexible materials, which increase the durability of the device. The prototype was tested at different excitation frequencies. Research has shown that at a frequency of 1.4 Hz, the optimal voltage and power are 126.28, 4.04 V, and 4.9 mW and 0.57 μW. 60 light emitting diode can be lit when pedestrians are walking. Therefore, PECEH can be used to collect the vibration energy of pedestrians while walking, providing power to sensors and microstructure. [ABSTRACT FROM AUTHOR]

AbstractAiming at the problems of high environmental vibration frequency, low output power and short life of the energy harvesters, a noncontact magnetically coupled piezo-electromagnetic rotary energy harvester is proposed in this paper. It consists of a base, a top cover, a rotating body, a cantilever beam, a permanent magnet, a coil, a hollow tube and a clamp. The novel hybrid harvester can produce both piezoelectric and electromagnetic energy at the same time, and in addition, it can efficiently generate electricity at low ambient vibration. Moreover, the piezoelectric material is protected from direct collision by noncontact magnetic coupling excitation. In order to conduct a comprehensive study on the performance of the piezoelectric-electromagnetic rotary energy harvester, we set up a rotating test platform to carry out systematic test verification, and to determine the distance between the permanent magnet and the rotating body and the number of permanent magnets on the rotating body. The test results show that when four permanent magnets are uniformly pasted on the rotating body and the rotating speed is 775 r/min, the piezoelectric and electromagnetic output power are 3.4 mW and 2.69 mW, respectively, and the total hybrid output power is 6.09 mW. [ABSTRACT FROM AUTHOR]

An array of published cell-based and small animal studies have demonstrated a variety of exposures of cancer cells or experimental carcinomas to electromagnetic (EM) wave platforms that are non-ionizing and non-thermal. Overall effects appear to be inhibitory, inducing cancer cell stress or death as well as inhibition in tumor growth in experimental models. A variety of physical input variables, including discrete frequencies, amplitudes, and exposure times, have been tested, but drawing methodologic rationale and mechanistic conclusions across studies is challenging. Nevertheless, outputs such as tumor cytotoxicity, apoptosis, tumor membrane electroporation and leak, and reactive oxygen species generation are intriguing. Early EM platforms in humans employ pulsed electric fields applied either externally or using interventional tumor contact to induce tumor cell electroporation with stromal, vascular, and immunologic sparing. It is also possible that direct or external exposures to non-thermal EM waves or pulsed magnetic fields may generate electromotive forces to engage with unique tumor cell properties, including tumor glycocalyx to induce carcinoma membrane disruption and stress, providing novel avenues to augment tumor antigen release, cross-presentation by tumor-resident immune cells, and anti-tumor immunity. Integration with existing checkpoint inhibitor strategies to boost immunotherapeutic effects in carcinomas may also emerge as a broadly effective strategy, but little has been considered or tested in this area. Unlike the use of chemo/radiation and/or targeted therapies in cancer, EM platforms may allow for the survival of tumor-associated immunologic cells, including naïve and sensitized anti-tumor T cells. Moreover, EM-induced cancer cell stress and apoptosis may potentiate endogenous tumor antigen-specific anti-tumor immunity. Clinical studies examining a few of these combined EMplatform approaches are in their infancy, and a greater thrust in research (including basic, clinical, and translational work) in understanding how EM platforms may integrate with immunotherapy will be critical in driving advances in cancer outcomes under this promising combination. [ABSTRACT FROM AUTHOR]

A novel wave energy harvester (WEH) that can recover energy in the direction of heave, sway, and surge is designed under the background of low recovery efficiency and complex installation of the existing wave energy harvester. The harvester consisted of four main components: energy input module, energy transfer module, energy conversion module, and energy store module. In the paper, to convert more wave energy into electrical energy and improve the energy conversion efficiency of WEH, the motion transfer module is divided into vertical and horizontal motion transfer modules, which are used to harvest vertical and horizontal wave energy, respectively. The vertical motion transfer module combined with the ball screw structure, planetary gear structure, and one-way gear units ensure the generator has high speed. The horizontal motion transfer module is mainly composed of three uniformly distributed one-way gear units, ensuring collect the wave energy in all horizontal directions. The dynamic model of the harvester is established, and the simulation experiment is carried out under wave conditions with periods of 2 s, 2.5 s, and 3 s, respectively. The simulation results show that when the wave period is 2 s, 2.5 s, and 3 s, the corresponding energy conversion efficiency of the WEH is 66.7%, 60.9%, and 57.1%, respectively. The proposed study provides a theoretical reference for modeling similar WEHs and can effectively balance energy supply and demand and further support the global agenda of UN-2030 for sustainable development, especially SDG-7. [ABSTRACT FROM AUTHOR]