Conversion Of Electromagnetic Energy Research Articles

Bidirectional, Multilayer MXene/Polyimide Aerogels for Ultra-Broadband Microwave Absorption.

To obtain high-performance electromagnetic microwave (EM) absorption materials with broad effective absorption bandwidth (EAB) and reduced thickness, designing structures has proved to be a promising way. Herein, ultra-broadband multilayer bidirectional MXene/polyimide EM absorption aerogels containing multi-structures on scales ranging from the micro- to the macroscale are produced with the aid of electric and temperature fields. On the microscale, under the action of electric force and temperature gradient, the ordered structures made of aligned Ti3C2Tx MXene nanosheets and the microscale layered aerogel walls enable the bidirectional aerogel to achieve a wide EAB of 8.58GHz at a thickness of 2.1mm. This is ascribed to the numerous aligned nanosheets and layered aerogel walls perpendicular to the incident EMs, facilitating the conversion of electromagnetic energy into electrical energy. Furthermore, on the macroscale, the multilayer bidirectional aerogel with non-gradient structures effectively resolves the conflict between impedance matching and energy loss, resulting in an ultrawide EAB of 9.41GHz at a thickness of 3mm. This innovative design of electric-field-assisted multilayer bidirectional aerogels with multiscale structural coupling may provide feasible and effective pathways for the development of advanced EM absorption materials.

Multidimensional hollow SiO2/C nanofibers modified by magnetic nanocrystals for electromagnetic energy conversion and lithium battery storage

Multidimensional hollow SiO2/C nanofibers modified by magnetic nanocrystals for electromagnetic energy conversion and lithium battery storage

Photobiomodulation on isolated mitochondria at 810 nm: first results on the efficiency of the energy conversion process

In this paper the photobiomodulation on isolated mitochondria of bovine liver is studied as a thermodynamic process of conversion of energy. This analysis is conducted by considering a particular set-up for the photobiomodulation experiments of interest. It allows, in particular, the computation of the electromagnetic field and the related energetic quantities in the stimulated organelles. The measurements of the excess of biochemical power density produced by the illuminated mitochondria are performed at regular time intervals after the experiments. The calculations and the measurements finally allow us to obtain the first results on the efficiency of the process of conversion of electromagnetic energy into excess of biochemical energy released by the isolated organelles.

Study on fused deposition modeling forming and properties of PP/RGO composite materials

Lightweight and efficient absorbing materials are considered a viable solution for mitigating electromagnetic wave pollution. Graphene, with its unique multi-layer structure, facilitates multiple reflections and scattering of electromagnetic waves, thereby enabling the conversion of electromagnetic wave energy into other forms. In this study, composite materials consisting of PP and RGO were prepared using FDM. The results revealed that PP-based composites exhibited favorable mechanical properties, with a tensile strength of 24.7 MPa and elongation at break of 28.8 %. For instance, at 5 % RGO content and a thickness of 2.1 mm, the composite material exhibited an absorption of −38.09 dB and 4 GHz. Notably, by varying the thickness within the range of 1–4 mm, the absorption bandwidth could cover a frequency range of 6–18 GHz. The combination of absorption and mechanical properties in these composite materials holds significant potential for the development of efficient and broadband absorption devices.

Flexible Ultrasonic‐Induced Wireless Energy Conversion Technology in Implantable Biomedicine

AbstractNumerous associated challenges arise with the advancement and continuous improvement of implantable medical devices, such as the frequent requirement for battery replacement. The flexible ultrasonic‐induced wireless energy conversion (UWEC) technology has garnered significant interest due to its superior energy transmission efficiency, safety, and biocompatibility compared to traditional electromagnetic wireless energy conversion technology. This paper provides a comprehensive review of the recent advancements in two types of flexible UWEC technologies, triboelectric nanogenerators, and piezoelectret nanogenerators, with a focus on their applications in implantable medical treatments. First, the energy conversion principles and general materials of flexible UWEC are presented. Then, the research and application of flexible UWEC devices are introduced in detail based on their medical functions. At the end of this review, perspectives and opportunities are discussed.

Bead-like Co/C@MoS2Composites connected by Multi-Walled carbon nanotubes for high-efficiency electromagnetic wave absorption

This study presents a novel approach to synthesize a composite material composed of bead-like Co/C nanoparticles anchored on MWCNTs, encapsulated by MoS2 nanosheets through a combination of carbonization and hydrothermal treatment using ZIF-67 as the precursor. The resulting composite demonstrates exceptional electromagnetic wave (EMW) absorption performance, with a minimum reflection loss (RL) of −63 dB at a thickness of 2.44 mm and an effective absorption bandwidth (EAB) of 7.2 GHz when RL is below 10 dB together with an expanded EAB of 12.3 GHz (d = 5 mm).The superior absorption capabilities arise from a well-thought-out design of material composition and structure. The synergy of Co/C and MWCNTs enhances ferromagnetic resonance, conductivity, and polarization loss, while sulfur vacancies in MoS2 act as polarization centers, facilitating dipole polarization and efficient conversion of electromagnetic wave energy. The core–shell structure and heterogeneous interfaces introduce various energy loss mechanisms, including multiple polarizations, scattering effects, and dielectric loss. This work introduces a facile method for synthesizing a composite material with outstanding EMW absorption performance. The synergistic combination of unique material components and the carefully engineered structure make this composite a promising candidate for advanced applications in electromagnetic wave absorption technology.

Multi-interfacial bridging engineering of flexible MXene film for efficient electromagnetic shielding and energy conversion

Accompanied by the progressive development of electronic equipment, excellent electromagnetic interference (EMI) shielding materials display a satisfying prospect in protecting electronic devices against electromagnetic pollution/radiation, while integrating energy conversion. Heretofore, it remains a conundrum to availably construct thin films with multi-interfacial bridging engineering as multifunctional shielding devices. To effectively achieve electromagnetic wave attenuation and integrate energy conversion, a co-mixed vacuum-assisted filtration strategy is designed to synthesize Au@MXene/cellulose nanocrystal/dodecylbenzenesulfonic acid-doped polyaniline (AMCP) films. Profited from the interfacial engineering, the total EMI shielding effectiveness (SE) can be increased by 27 % with the highest value of 67.9 dB. MXene with localized surface plasmon resonance characteristics gives the composite films good energy conversion performance, that is, the composite film can be rapidly heated up to 100 °C under the irradiation of an infrared lamp, and its surface temperature remains stable after continuous irradiation. Additionally, the infrared emissivity is as low as 0.173 within the 8–14 μm, which is necessary to adapt various application scenarios. Therefore, it is reliable that the AMCP films constructed by multicomponent offer a facile strategy for MXene-based EMI shielding devices with integration characteristics.

Heterodimensional hybrids assembled with multiple-dimensional copper selenide hollow microspheres and graphene oxide nanosheets for electromagnetic energy conversion and electrochemical energy storage

Heterodimensional hybrids assembled with multiple-dimensional copper selenide hollow microspheres and graphene oxide nanosheets for electromagnetic energy conversion and electrochemical energy storage

Design and analysis of an electromagnetic energy conversion device

In this study,we introduces an innovative device designed for wave-heat-electricity conversion, incorporating a classical split-ring resonator (SRR) and a Bi2Te3 semiconductor strip. This configuration is adept at absorbing electromagnetic energy, transforming it into thermal energy, and facilitating an electrical response. The paper delves into the detailed physical modeling and operational principles of the device. We begin by employing an equivalent circuit model to analyze the SRR's transmission characteristics and its temperature response under specific conditions. The investigation further extends to examining how structural dimensions and material properties affect the development of a local hotspot, leading to the refinement of the SRR resonant unit. We then integrate a Bi2Te3 semiconductor strip beneath this hotspot, enhancing the device's conversion capabilities. Our findings indicate an absorption efficiency of 0.085 at 2.45 GHz, a remarkable thermal conversion efficiency of 172.8 °C/W, and an electrical conversion efficiency of 0.195 mV/°C, all measured at an input power of 7 W. This research not only demonstrates the efficacy of the proposed device in wave-heat-electricity conversion but also provides a comprehensive reference for future advancements in this field.

Multifunctional WSe2/Co3C composite for efficient electromagnetic absorption, EMI shielding, and energy conversion

Multifunctional WSe2/Co3C composite for efficient electromagnetic absorption, EMI shielding, and energy conversion

Optimum Design of a Reusable Spacecraft Launch System Using Electromagnetic Energy: An Artificial Intelligence GSO Algorithm

Due to its advantages of high acceleration, reusability, environmental protection, safety, energy conservation, and efficiency, electromagnetic energy has been considered as an inevitable choicefor future space launch technology. This paper proposes a novel three-level orbital launch approach based on a combination of a traditional two-level orbital launch method and an electromagnetic boost (EMB), in whichthe traditional two-level orbital launch consists of a turbine-basedcombined cycle (TBCC) and a reusable rocket (RR). Firstly, a mathematical model of a multi-stage coil electromagnetic boost system is established to develop the proposed three-level EMB-TBCC-RR orbital launch approach, achieving a horizontal take-off–horizontal landing (HTHL) reusable launch. In order to optimize the fuel quality of the energy system, an artificial intelligence algorithmparameters-sensitivity-basedadaptive quantum-inspiredglowworm swarm optimization (AQGSO)is proposed to improve the performance of the electromagnetic boosting system. Simulation results show that the proposed AQGSO improves the global optimization precision and convergence speed. By using the proposed EMB-TBCC-RR orbital launch system and the optimization approach, the required fuel weight was reduced by about 13 tons for the same launch mission, and the energy efficiency and reusability of the spacecraft was greatly improved. The spacecraft can be launched with more cargo capacity and increased payload. The proposed novel three-level orbital launch approach can help engineers to design and optimize the orbital launch system in the field of electromagnetic energy conversion and management.

Research on electromagnetic energy absorption and conversion device with four-ring multi-resistance structure

A device for electromagnetic energy absorption and conversion was investigated as an electromagnetic energy harvester, which is based on a four-ring multi-resistance unit. The device can convert microwave energy to thermal energy and then to electrical energy through the Bi2Te3 thermoelectric material adhered to the load resistance. The energy harvesting efficiency, power loss distribution, and current density distribution of the harvester were analyzed. In addition, the energy harvesting efficiency of the unit under different incident angles and polarization angles was studied, and the effect of incident power on the temperature and energy conversion efficiency of the unit was analyzed. The simulation results showed that the energy harvesting efficiency of the harvester reaches 99.5% at 5.8 GHz. Each unit in the harvester can generate an output voltage of 171.8 mV under 7 W incident wave power, and the maximum output power is 9.71 mW. To verify the effectiveness of this method, a 5 × 5 unit array model was fabricated and measured, and the measurement results were consistent with the simulation results.

Resonant Scattering of Gravitational Waves with Electromagnetic Waves

A certain class of exact solutions of Einstein Maxwell spacetime in general relativity is discussed to demonstrate that at the level of theory, when certain parametric resonance condition is met, the interaction of electromagnetic field with a gravitational wave will display certain Lyapunov instability and lead to exponential amplification of a gravitational wave train described by certain Newman–Penrose component of the Weyl curvature. In some way akin to a free electron laser in electromagnetic theory, by the conversion of electromagnetic energy into gravitational energy in a coherent way, the feasibility of generating a pulsed-laser-like intense beam of gravitational wave is displayed.

Wave-heat-electricity conversion: Design and analysis of an electromagnetic energy conversion device

An innovative electromagnetic energy harvester was developed using a compact four-ring single-resistor unit cell. To achieve efficient conversion of electromagnetic waves into electricity, we integrated the high-performance Bi2Te3 thermoelectric material onto the load resistor. Remarkably, this unit cell exhibits exceptional energy harvesting capabilities at a frequency of 5.8 GHz while maintaining polarization insensitivity. Through comprehensive analysis, we evaluated the energy harvesting efficiencies, power loss distribution, and current density distribution. Additionally, we investigated the impact of incident power on the unit cell's temperature and energy conversion efficiencies. To enhance energy concentration on the load, we ingeniously designed an “L-shaped” metal through-hole structure within the four-ring single-resistor unit cell. Our results demonstrate that the four-ring single-resistor unit cell achieves an impressive harvesting efficiency of 94.5% at 5.8 GHz, with a thermal conversion efficiency of 43.3 °C/W, an electrical conversion efficiency of 0.23 mV/°C, and an electrical response rate of 9.4 mV/W. Notably, when subjected to a power input of 7 W, the unit cell produces an output voltage of 65.9 mV, and its theoretical maximum output power reaches 180 mW.

Electromagnetic Conversion into Kinetic and Thermal Energies.

The conversion of electromagnetic energy into magnetohydrodynamic energy occurs when the electric conductivity changes from negligible to finite values. This process is relevant during the epoch of reheating in the early universe at the end of inflation and before the emergence of the radiation-dominated era. We find that the conversion into kinetic and thermal energies is primarily the result of electric energy dissipation, while magnetic energy only plays a secondary role in this process. This means that since electric energy dominates over magnetic energy during inflation and reheating, significant amounts of electric energy can be converted into magnetohydrodynamic energy when conductivity emerges before the relevant length scales become stable.

Biomass composite based on metallized bamboo fiber for electromagnetic interference shielding, joule heating, and solar heating

The energy and environmental problems brought by petrochemical products promote the development of green and sustainable materials. Natural fiber reinforced plant-derived polylactic acid (PLA) is an attractive sustainable strategy. However, the lack of functionality largely limits its wider application. In this study, the most promising bamboo fiber (BF) whose versatility was realized by electroless plating (ELP) was selected as the reinforcing phase. By filling metallized BF(MBF) into PLA and then treating it by hot pressing, a low-cost, multifunctional MBF/PLA biomass composite(MBPC) was prepared. Results show that the ELP treatment of BF can not only significantly improve the thermal stability and mechanical properties of the composites but also endow it with excellent electromagnetic shielding, electro-thermal and photo-thermal conversion capabilities. Thereinto, the 70 wt%-MBPC has an electrical conductivity of 20.86 S/cm and an SE value of 45 dB in the X-band. The greater concern is the amazing electrothermal conversion performance, which can be heated rapidly at low voltage. Under the voltage of 3V, the temperature reaches 160 °C in about 50s. Besides, MBPC also possesses solar-driven heating, which can be rapidly heated to 75 °C under irradiation within 240s. This green and low-cost biomass multifunctional composite is expected to be used for electromagnetic shielding, energy conversion, and smart furniture, etc.

Electron energy dissipation in a magnetotail reconnection region

The four Magnetospheric Multiscale spacecraft encountered a reconnection region in the Earth's magnetospheric tail on 11 July 2017. Previous publications have reported characteristics of the electron diffusion region, including its aspect ratio, the reconnection electric field, plasma wave generation from electron beams in its vicinity, and energetic particles in the Earthward exhaust. This paper reports on the investigation of conversion of electromagnetic energy to electron kinetic energy (by J·E) and the ensuing conversion of electron beam energy to electron thermal energy via the pressure–strain interaction. The main result is that omnidirectional, compressive dissipation of electron energy dominates in the positive J·E region, while incompressive parallel dissipation dominates in the inflow region where J·E is small. The existence of parallel electric fields in the inflow region supports previous suggestions that electron trapping by these fields contributes to the parallel dissipation. All of the results are reproduced quantitatively within a factor of two with a 2.5-D particle-in-cell simulation.

The proof of concept of uninterrupted push‐pull electromagnetic propulsion and energy conversion systems for drones and planet landers

AbstractAlthough numerous models of aerial‐robots/drones and planet landers have been demonstrated to fly autonomously in natural and manmade environments for far‐reaching scientific and technological change to help humankind, no drone flowed yet with a push‐pull dual‐head electromagnetic propulsion (EMP) system ensuring unrestricted flight endurance. The precept of EMP is eminent as it hastens an object using a flowing electrical current, either to charge a field or opposing a magnetic field for locomotive use. Here we present a proof of concept to demonstrate the capability of a newly invented variable speed propulsion and energy conversion system for uninterruptedly generating the reciprocating motion of a magnetic piston by a solar battery‐driven polarity changer timing circuit together with a laser‐based timing circuit for redundancy. The reciprocating crusade of the magnetic piston could be successfully converted into rotary motion to generate continuous power for various multidisciplinary applications on Earth and the other planets effectively in lieu of long‐lasting rechargeable batteries. The proposed concept can also be used for devising various systems and subsystems from underwater to outer space by using light weight supermalloy, which ensures high magnetic fluxes with relatively low current. Lucrative applications include nanomaterial‐enabled locomotive applications. Aerial robots regulated with the EMP system could be used for fostering pharmaceutical florae in the international space station for drug design to negate the recently discovered phenomenon of Sanal flow choking in cardiovascular system at gravity and/or microgravity conditions. This concept is originated from mind and aimed for lucrative product developments of yocto to yotta scale energy systems and beyond by discovering new magnetic materials through the fourth industrial revolution. Herein, a proof of the concept of an unrestricted solar‐battery driven push‐pull electromagnetic propulsion and energy conversion device by use of light weight high power magnetic materials is presented.

Graphene Implanted Shape Memory Polymers with Dielectric Gene Dominated Highly Efficient Microwave Drive

AbstractMicrowave‐driven strategy shows many advantages including selective energization, uniform heating, and high penetration depth, which is a hot topic in wireless actuators. Understanding microwave stimulus‐response mechanisms is the key to developing universal construction strategies for advanced microwave‐driven actuators. Herein, reduced graphene oxide (rGO) with specified dielectric genes and thermal properties is implanted into the shape memory polymer, liquid crystal elastomer (LCE) as an example, to construct soft, reversible, and sensitive microwave actuators. Based on the analysis of microstructure and dielectric properties, LCE‐rGO composites exhibit excellent polarization relaxation‐dominated dielectric loss and electromagnetic (EM) energy conversion ability. The maximum dielectric loss factor (ε″) and loss tangent (tan δe) of LCE‐rGO are dramatically increased by 216% and 87.5% compared to pure LCE, respectively, and the optimum apparent energy harvest efficiency is 19.4 times higher than that of LCE. In addition, the implantation of rGO significantly lowers the microwave actuation threshold of LCE‐rGO composites and reinforces their stimulus‐response capacity. Response time under 750 W microwave irradiation of LCE‐rGO is shortened to <10s. These findings can provide a solid basis for the design and fabrication of highly efficient microwave stimuli‐responsive polymers and enlighten a new approach to wireless actuated smart devices.

Controlled Synthesis of MOF-Derived Nano-Microstructure toward Lightweight and Wideband Microwave Absorption.

Correlating metal-organic framework (MOF) synthesis processes and microwave absorption (MA) enhancement mechanisms is a pioneer project. Nevertheless, the correlation process still relies mainly on empirical doctrine, which hardly corresponds to the specific mechanism of the effect on the dielectric properties. Hereby, after the strategy of modulation of protonation engineering and solvothermal temperature in the synthesis route, the obtained sheet-like self-assembled nanoflowerswereconstructed.Porous structures with multiple heterointerfaces, abundant defects, and vacancies are obtained by controlled design of the synthesis procedure. The rearrangement of charges and enhanced polarization can be promoted. The designed electromagnetic properties and special nano-microstructures of functional materials have significant impact on their electromagnetic wave energy conversion effects. As a consequence, the MA performance of the samples has been enhanced toward broadband absorption (6.07GHz), low thickness (2.0mm), low filling (20%), and efficient loss (-25dB), as well as being suitable for practical environmental applications. This work establishes the connection between the MOF-derived materials synthesis process and the MA enhancement mechanism, which provides insight into various microscopic microwave loss mechanisms.