Electromagnetic Mass Research Articles

Angular momentum of a circularly polarized light beam

It is shown that the Maxwell electrodynamics cannot explain the existence of an angular momentum flux in a circularly polarized light beam which has no the phase structure. The fact is that such a beam contains a small rotating electromagnetic mass and, accordingly, contains an angular momentum directed along the beam axis, but this rotating mass has no speed in the direction of the beam axis. Therefore, this angular momentum is not transferred along the beam axis, and there is no flow of this angular momentum along the beam axis. We show the angular momentum flux in such a beam is contained in the main mass of the beam, which does not rotate. This angular momentum flux is a spin flux and is described by the spin tensor. Likewise, taking spin into account is required to explain the classical Beth experiment and other experiments.

Increasing the underground coal gasification efficiency using preliminary electromagnetic coal mass heating

The purpose of this research is to explore the possibilities of using a high-frequency electromagnetic field for heating coal seams in the context of underground coal gasification. The research is based on mathematical models that take into account the physical parameters of the electromagnetic field. The methodology includes the calculation of thermal powers, exposure duration, temperature profiles and reaction rates. The research results indicate significant potential for using high-frequency electromagnetic field for coal seam pre-heating. Possibilities of using a high-frequency electromagnetic field for heating the mass in the context of underground coal gasification have been explored. The mathematical models developed and calculations performed broaden the understanding of heating processes in such systems. It has been determined that field parameters, such as frequency and power, influence the heating efficiency and temperature distribution. The obtained scientific results present new opportunities to increase the efficiency of underground coal gasification as an alternative energy source and will contribute to achieving a more efficient and sustainable future energy supply. The use of a high-frequency electromagnetic field can be useful when gasifying low-grade or low-thickness coal seams, when there is a need to intensify the gasification process.

Efficient Extraction and Analysis of Nanoplastics by Ionic Liquid-Assisted Cloud-Point Extraction Coupled with Electromagnetic Heating Pyrolysis Mass Spectrometry.

Nanoplastics have attracted much attention due to their potential hazards. However, analysis of nanoplastics remains challenging. In this study, ionic liquid-assisted cloud-point extraction (IL-assisted CPE) was developed to enrich nanoplastics in the aqueous environment and further coupled with electromagnetic heating pyrolysis mass spectrometry. The use of trace ILs improves the extraction efficiency of CPE for nanoplastics. The effects of ILs (types, contents), nanoplastic properties (type, size), and environmental factors (aging time, humic acid content) were systematically investigated to evaluate the applicability. The limits of detection of poly(methyl methacrylate) (PMMA) and polystyrene (PS) were determined to be 1.78 and 2.67 μg/L, respectively. Real environmental samples including lake water, rainwater, and influent and effluent from wastewater treatment plant were analyzed with good accuracy (79.58-116.87%) and satisfactory precision (RSD ≤ 11.99%). A possible mechanism for ILs being absorbed into the ordered surfactant micellar and generating larger micelles to synergically enclose hydrophobic nanoplastics was proposed. This work provides a simple and efficient approach to the extraction and analysis of nanoplastics in aqueous environments.

Heating uniformity improvement of the intermittent microwave drying for carrot with simulations and experiments

AbstractHeating uniformity is always a concern in microwave drying for foodstuff, where unsatisfied product quality could be caused by over‐ or inadequate‐heating. To deal with this concern, multi‐physics field rotation simulation models and intermittent microwave drying modes were designed and evaluated in this study. Four drying modes with different intermittent time ratios (R1/2, R1/3, R1/4, and R1/5) were first applied in drying experiments. Their effects on temperature distribution, drying characteristics, and quality aspects (chromatic aberration, rehydration ratio, vitamin C content, and sensory evaluation) for carrot samples were compared and analyzed. The results revealed that the carrot quality in R1/4 mode drying was increased by up to 64% in comparison with the other three modes. The root‐mean‐square error of the moisture ratio was maintained at a lower value, and a better consistency was also achieved in R1/4 mode. To further improve the drying performance and efficiency, a novel stage intermittent‐time control strategy was attempted, that is, an appropriate strategy was used in each drying stage. With this method, the best drying effect could be obtained. The above work can promote a deeper understanding of the drying kinetic and provide novel operation strategies in the microwave drying of food products.Practical applicationsA multi‐physics field rotational simulation model (MFRSM) coupled with an intermittent microwave drying process, including electromagnetic heating, heat, and mass transfer, was developed to characterize the drying process of rotating samples in an intermittent microwave dryer. The MFRSM was helpful to analyze the continuous microwave drying process of the sample and deepen the understanding of the internal heat and mass transfer process of the sample. Four modes with different intermittent schedules were designed, and simulation models were also established. The drying characteristics in different modes were analyzed; a long intermittent time could affect the drying efficiency on account of the driving force, while a short intermittent time would reduce the product quality because of the continuous high temperature. R1/4 mode was founded in terms of drying efficiency and drying quality. An optimized stage intermittent‐time control strategy (R‐IO mode) was designed. The drying time in the three stages was shortened by 25% in total compared with R1/4 mode. Meanwhile, the vitamin C retention, the taste quality of the dried products were improved. These works are expected to provide benefits for the understanding of the intermittent microwave drying modes on drying kinetic using the MFRSM. It can also be useful in the development of an IMD for food materials.

A nonlinear analysis of a Duffing oscillator with a nonlinear electromagnetic vibration absorber–inerter for concurrent vibration mitigation and energy harvesting

Several investigators have taken advantage of electromagnetic shunt-tuned mass dampers to achieve concurrent vibration mitigation and energy harvesting. For nonlinear structures such as the Duffing oscillator, it has been shown that the novel nonlinear electromagnetic resonant shunt-tuned mass damper inerter (NERS-TMDI) can mitigate vibration and extract energy for a wider range of frequencies and forcing amplitudes when compared to competing technologies. However, nonlinear systems such as the NERS-TMDI are known to exhibit complex stability behavior, which can strongly influence their performance in simultaneous vibration control and energy harvesting. To address this problem, this paper conducts a global stability analysis of the novel NERS-TMDI using three approaches: the multi-parametric recursive continuationWe emphasize that these assume method, Floquet theory, and Lyapunov exponents. A comprehensive parametric analysis is also performed to evaluate the impact of key design parameters on the global stability of the system. The outcome indicates the existence of complex nonlinear behavior, such as detached resonance curves, and the transition of periodic stable solutions to chaotic solutions. Additionally, a parametric study demonstrates that the nonlinear stiffness has a minimal impact on the linear stability of the system but can significantly impact the nonlinear stability performance, while the transducer coefficient has an impact on the linear and nonlinear stability NERS-TMDI. Finally, the global sensitivity analysis is performed relative to system parameters to quantify the impact of uncertainty in system parameters on the dynamics. Overall, our findings show that simultaneous vibration control and energy harvesting come with a considerable instability trade-off that limits the range of operation of the NERS-TMDI.

Proposal for an Electromagnetic Mass Formula for the X17 Particle

Recent observations of anomalous angular correlations of electron–positron pairs in several nuclear reactions have indicated the existence of a hypothetical neutral boson of rest mass ~17 MeV/c2, called the X17 particle. Similarly, one has interpreted an independent set of experiments on photon pair spectra around the invariant mass ~38 MeV/c2, by assuming the existence of the so-called E38 particle. In the present paper, we derive analytical mass formulas for the X17 particle and the E38 particle, on the basis of quantum electrodynamics. We shall use the exact solutions of the Dirac equation of the joint system of a charged particle and plane waves of the quantized electromagnetic radiation. When these solutions are applied to a proton, they lead to dressed radiation quanta with a rest mass of 17.0087 MeV/c2, which may be identified with the X17 vector bosons. A similar consideration, applied to the udd quarks of the neutron, yields dressed quanta, whose mass equals 37.9938 MeV/c2, corresponding to the E38 particle. These formulas, besides the Sommerfeld fine structure constant and the masses of the nucleons, do not contain any adjustable parameters. The present analysis also delivers the value 0.846299 fm for the proton radius.

Detection of nanoplastics released from consumer plastic food containers by electromagnetic heating pyrolysis mass spectrometry

Nanoplastics released from consumer plastic food containers are emerging environmental pollutants and directly ingested as part of the diet. However, quantification methods for nanoplastics are still lacking. Herein, a rapid identification and mass quantification approach was developed for nanoplastics analysis by combining electromagnetic heating with pyrolysis mass spectrometry (Eh-Py-MS). The pyrolysis products directly entered into the MS, which omits the gas phase separation process and shortens the detection time. A compact pyrolysis chamber was used and this increased the sample transfer efficiency and lowered power requirement. The operational parameters were systematically examined. The influence of nanoplastic size, additive, humic acid, and aging on detection was investigated, and it was concluded that environmental factors (humic acid, aging) and plastic properties (size, additives) did not influence the detection. The developed chamber showed that the limit of detection of polystyrene (PS) nanoplastics was 15.72 ng. Several typical food packages were demonstrated with satisfactory recovery rates (87.5–110%) and precision (RSD ≤11.36%). These results suggested that the consumer plastic food containers are a significant source of direct exposure to nanoplastics in humans from the environment.

Mass Shift, Coupled to Electromagnetic Field Mass, and Temporal Superposition

In this paper I consider two ideas of time travel, which is highly speculative, that gravity might diverge backward in time (and therefore having a speed in excess of light), and having negative potential energy, while all ordinary bodies have positive mass. As we move forward in time, we experience gravity as a converging force. If the mass of a body were engineered to diverge backwards in time with gravity, one would have a form of time travel. One considers the electromagnetic field mass as having a gravitational field, whereby if one could mass shift mass of and capacitor, one would experience a gravitational field that might diverge backwards in time. The 2nd idea of time travel regards quantum superposition of particles, being everywhere in space. I consider temporal superposition of particles anywhere in time, that if quantum superposition can be done with larger objects in the future, such objects could be teleported anywhere in time, e.g. the past.

Stochastic Optimization of Electromagnetic Inertial Mass Dampers in Nonlinear Hybrid Base Isolation Systems Under Seismic Excitations

Recently developed inerter-based dampers have been installed at the base layer to reduce base displacement and simultaneously improve the superstructure’s performance. However, in the existing research on optimizing damper parameters, the nonlinear property of base isolation is simplified and stochastic linearization technique is introduced to approximate such nonlinearity, which would inevitably introduce errors. In this paper, an improved method is proposed for stochastic optimization of electromagnetic inertial mass dampers (EIMD) in nonlinear hybrid isolation systems subject to seismic excitations. First, a stochastic seismic excitation is represented by one elementary random variable adopting the dimension-reduction spectral representation method. Then, statistical moments of nonlinear base-isolated structural responses are estimated using two-point estimation method (2PEM). Finally, the EIMD optimal parameters are obtained via the modified directional bat algorithm (MDBA) recently proposed by the authors through minimizing base layer response moments. This proposed improved method could fully consider the base isolation nonlinearity compared with the previous stochastic linearization technique. Moreover, the proposed stochastic optimization of the EIMD only requires two dynamic analyses to achieve its efficiency. A seven-story base-isolated frame building equipped with an EIMD is investigated in the numerical simulation, and results indicate that EIMD optimized by this proposed method obviously outperforms the results by the stochastic linearization technique and the conventional viscous damper (VD) in the base layer displacement reduction.

Investigation of a new magnetorheological elastomer metamaterial plate with continuous programmable properties for vibration manipulation

Metamaterial plates have attracted considerable attention due to their unprecedented elastic wave manipulation abilities. Currently, the band gap and other properties of traditional metamaterial plates are fixed, and the material parameters of most metamaterials cannot be dynamically and continuously adjusted. To address this issue, a two-dimensional (2D) magnetorheological elastomer (MRE) programmable metamaterial plate (MREPMP) with local resonance was proposed. The proposed MREPMP was composed of a thin steel plate and a periodic array of resonators, consisting of MREs and electromagnetic mass blocks. It not only has a compact structural design, but also enables real-time vibration control and programming wave manipulation by altering the amplitude of the current. The dispersion relation of the proposed MREPMP was theoretically calculated based on the plane wave expansion (PWE) method and the simulated transmissibility was numerically calculated using the finite element method in COMSOL. Subsequently, a prototype of the MREPMP was fabricated, and vibration tests were conducted to assess its programmable vibration manipulation functionalities. Two different types of defect paths were used as excitations and the corresponding real-time vibration manipulation performance was analyzed. The simulation results agree with the experimental results, showing that the MREPMP can dynamically tune the band gap and activate different waveguides through continuous online programming. This paper opens up a new idea for tunable manipulation of wave propagation.

Electromagnetic Design and Analysis of Inertial Mass Linear Actuator for Active Vibration Isolation System

Underwater radiated noise from anthropogenic structures must be reduced to protect the marine environment. Active vibration isolation that can reduce noise generated from vibration sources by providing counteracting forces can solve this issue. This paper presents a 120 N class electromagnetic inertial mass linear actuator for an active vibration control system in a large ship. The proposed actuator is operated based on the Lorentz force, also known as electromagnetic force. To achieve a high thrust force to weight ratio, a permanent magnet with outer radial magnetization is used. In order to design and analyze the proposed model, a simple magnetic equivalent circuit analysis was first conducted to achieve an appropriate force, and its value was compared and verified with the magnetostatic finite element method. The dynamic characteristics of the actuator were then evaluated, and the performance was analyzed at various operating frequency points. The bobbin housing supporting the coil causes an eddy current loss due to materials with electrical conductivity. As a result, the damping force is generated by the reduction in magnetic flux, and the control force tends to decrease.

Isospin mass differences of the B, D and K

We compute the electromagnetic mass difference for the B-, D- and K-mesons using QCD sum rules with double dispersion relations. For the B- and D-mesons we also compute the linear quark mass correction, whereas for the K the standard soft theorems prove more powerful. The mass differences, which have not previously been computed via a double dispersion, are fully consistent with experiment, albeit with large uncertainties.

Improved Three-Variable Control for Electromagnetic Mass Damper System Considering Control–Structure Interaction

Current methods account for control–structure interaction (CSI) in structural control design, which may be unavailable in the preliminary design phase of actively controlled structures due to the unknown dynamic characteristic of an actuator. Therefore, it may result in significant difference in the design and evaluation of an active structural control system when ignoring or considering CSI at different phases. To eliminate the CSI effects of electromagnetic mass damper (EMD) system and thus decouple the tracking control of EMD from the control design of structure, in this paper, an improved three-variable control (ITVC) combining a signal convertor, a typical three-variable controller, and a voltage compensator is developed. The voltage compensator counteracts the influence of lower-order CSI including viscous damping force and Coulomb friction. The three-variable controller reduces the higher-order CSI effects, while the signal convertor converts all command and feedback signals to the relative coordinate system and eliminates the additional CSI effects. Performance tests and frequency response tests of the EMD system show that the CSI effects are basically eliminated by ITVC. In addition, shake table tests are performed on a one-story actively controlled structure to further verify ITVC. Experimental results suggest that ITVC can apply accurate control force on the structure and achieve ideal structural response control.

Launch parameters of a lunar ice payload traveling via electromagnetic mass accelerator

This paper describes a solution for procuring propellent needed for future space exploration missions based on the Lunar Electromagnetic Mass Accelerator (LEMMA) concept analyzed by McNab and McGlasson. This study examined the feasibility of using an electromagnetic launcher (EML) to transport raw materials used in propellent production from the lunar south pole to the National Aeronautics and Space Administration's (NASA) Lunar Gateway. The proposed Gateway space station, to be located in a lunar near-rectilinear halo orbit (NRHO), is a critical part of NASA's Artemis program. Cheaply and efficiently sourcing lunar hydrogen from surface ice to the Gateway would benefit the program's success and future exploration of the solar system. Our study of the launch requirements for a lunar EML payload are described here. AGI Inc's Systems Tool Kit (STK) was used to calculate the required launch azimuth, elevation, magnitude, epoch, and trip duration for a payload launched from the Moon to rendezvous with Gateway. The study shows that it is feasible to conduct a single launch from the lunar south pole that can intercept any point along the Gateway's orbit with variable launch conditions.

A composite control scheme for electromagnetic active mass damper against control-structure-interaction effects

Existing methods account for control-structure-interaction (CSI) in structural control design. However, their implementations may be challenging since the dynamic characteristics of actuator are unavailable in the preliminary design phase of actively controlled structures. In this study, a composite control scheme (CCS) is proposed to eliminate the CSI effects of electromagnetic active mass damper (AMD), and thus decouple the tracking control of AMD from the control design of structure. In the CCS, force compensation is performed to counteract the influence of lower-order CSI including the damping force and friction, while hierarchical control comprised of low-level feed-forward/feedback control and high-level sliding mode control is designed to reduce the higher-order CSI effect and achieve a high-performance force control. Performance tests and frequency response tests of the electromagnetic AMD system indicate that the CSI effects are significantly reduced by the proposed CCS. Furthermore, shake table tests are conducted on a two-story actively controlled structure to verify the effectiveness of CCS. Experimental results show that the proposed CCS can apply accurate control force to the structure, which contributes to an ideal structural response control.

Stochastic Optimization of a Nonlinear Base Isolation System with LRB and EIMD for Building Structures

Base-isolated structures achieve superior seismic performance but with the cost of large deformation of the base floor, which possibly causes superstructure collapse during severe earthquakes. Hence, it is of great interest to develop hybrid base isolation systems that can reduce the base deformation and simultaneously improve the superstructure’s performance. Recently, several hybrid base isolation systems using inerter-based dampers have emerged; however, the nonlinear performance of the isolators has rarely been considered in these studies. In this paper, we conduct a nonlinear stochastic optimization of a novel hybrid base isolation system with lead-rubber bearings (LRB) and electromagnetic inertial mass dampers (EIMD). Based on the Bouc–Wen hysteretic model of the LRB, we derive the semianalytical solutions of the response variances of a simplified base-isolated model subjected to stationary seismic excitations. Then, based on the semianalytical solutions, we propose a procedure for optimizing the EIMD aimed at minimizing the superstructure interstory drift. In addition, we investigate the effect of site conditions and postyielding to preyielding stiffness ratios of the LRB on the optimal EIMD parameters and corresponding seismic performance. It is found that the hybrid base isolation system achieves better performance at a soft site than at a firm site. Results of a hybrid base-isolated building under artificial and real earthquake excitations illustrate that the EIMD can reduce both the base deformation and superstructure response, which outperforms the hybrid base-isolated building with conventional viscous dampers (VD).

Proton quark distributions from a light-front Faddeev-Bethe-Salpeter approach

The projection onto the Light-Front of a Minkowski space Faddeev-Bethe-Salpeter equation model truncated at the valence level is applied to study the proton structure with constituent quarks. The dynamics of the model has built-in: (i) a bound diquark brought by a contact interaction, and (ii) the separation by ∼ΛQCD of the infrared and ultraviolet interaction regions. The model parameters are fine tuned to reproduce the proton Dirac electromagnetic form factor and mass. From that, the non-polarized longitudinal and transverse momentum distributions were computed. The results for the evolved non-polarized valence parton distributions suggest that: (i) the explicit consideration of the spin degree of freedom of both quark and diquark seems not relevant to it, and (ii) the comparison with the global fit from the NNPDF4.0 calls for higher Fock components of the wave function beyond the valence one.

Heat and mass transfer law during microwave vacuum drying of rice

In order to obtain the microwave vacuum drying characteristics of rice and the change in law of temperature and humidity, the mechanism of water diffusion and migration in the drying process was analyzed based on the multiphase flow in porous media, the change model of moisture content was established, and the microwave heating process coupled with electromagnetic field and mass heat field was simulated. The accuracy of the multiphase porous medium model was verified by measuring the moisture changes during rice drying under different vacuum degrees. The results show that the temperature distribution of rice during heating is high in the center and low around, and the vacuum degree hardly affects the change in rice temperature. The capillary pressure in rice gradually increases, and the equilibrium vapor pressure gradually decreases during drying. The estimated moisture content reduced from 0.25 to 0.189, 0.177, and 0.169, and the experimental value decreased from 0.25 to 0.186, 0.177, and 0.167 after drying the rice for 60 min at vacuum of 0.02 MPa, 0.04 MPa, and 0.06 MPa, respectively. The experimental value was in agreement with the calculated value. The higher the vacuum degree, the faster the drying speed, and this finding provided a new idea for improving the drying efficiency.

Design Approach and Practical Formulas of Electromagnetic Inertial Mass Dampers for Cable Multimode Control

Design Approach and Practical Formulas of Electromagnetic Inertial Mass Dampers for Cable Multimode Control

Response control of a transmission tower-line system under wind excitations by electromagnetic inertial mass dampers

Structural vibration of transmission tower-line systems under wind excitations may induce damage and even destruction of the overall system. The control of transmission towers is conducted in the past decades by dynamic absorbers and dampers. Recently, a new type of passive control device, namely electromagnetic inertial mass dampers (EIMD), has been proposed and applied in structural vibration control However, the EIMD has not yet been systematically investigated in the vibration control of power transmission towers. In this regard, the vibration control of wind-disturbed transmission towers using EIMDs is conducted. The analytical model of a real tower-line system is established in line with the Hamilton principles. The response control approach using EIMDs is proposed and the control performance of different methods is compared in both the time and frequency domain. Detailed parametric studies are carried out to examine the effects of electromagnetic damping, inertial mass, and wind load intensity on EIMD performance. The assessment of the system energy responses without and with control is also conducted. The made observations demonstrate that the application of EIMDs can significantly reduce the structural dynamic responses under wind loading and the control performance of the EIMDs is quite robust and versatile under different wind load intensities.