Complex Electromagnetic Field Research Articles

Anticancer Activities of Cu(II) Complex-Schiff Base and Low-Frequency Electromagnetic Fields and the Interaction Between Cu(II) Complex-Schiff Base with Bovine Serum Albumin by Spectroscopy.

Cancer is the consequence of abnormal cell proliferation, which leads to the formation of abnormal mass. In this study, we aimed to determine the anticancer properties of Cu(II)-Schiff base complex and low-frequency electromagnetic field, and the interaction between BSA and Cu(II) complex. Firstly, Schiff base of the Cu(II) complex in the N,N'-dipyridoxyl(1,2 diaminobenzene) was originally synthesized. Following, the breast cancer was transplanted with the TUBO cells in vivo. Then, treatment of the cancerous mice was done by low-frequency electromagnetic field and the Cu(II)-Schiff base complex. In this project, antiproliferative activity on breast cancer cells was tested by TUBO cells using MTT assay and apoptosis properties were studied by flow cytometry. The interaction between the Cu(II)-Schiff base complex and bovine serum albumin (BSA) was checked by fluorescence and UV-vis absorbance spectroscopy. Tumor tissue investigation demonstrated that the low-frequency electromagnetic field and Cu(II)-Schiff base complex induce apoptosis and inhibit tumor growth. MTT results unveiled a cytotoxic impact on breast cancer cells. Flow cytometry analysis demonstrates that the anticancer effect of Cu(II)-Schiff base complex on breast cancer cells (MCF7) was associated with the cell cycle arrest. The results of fluorescence spectra and UV-vis absorption spectra showed that the conformation of bovine serum albumin has been changed in the presence of Cu(II)-Schiff base complex. Cu(II)-Schiff base complex and low-frequency electromagnetic field have anticancer properties. The spectroscopy method indicates the binding between Cu(II)-Schiff base complex and BSA.

Research on Functional Robustness of Heterogeneous Combat Networks

The combat system-of-systems in high-tech informative warfare consists of different types of combat systems connected via multiple interconnections, which can be abstracted as types of complex heterogeneous networks. Research on the functional robustness of heterogeneous combat networks (HCNs) is of significant military value for optimizing operation process planning and for improving network survivability in complex electromagnetic battle fields. This study presents an integrated framework, known as the HCN functional robustness (HCNFR) framework to measure the functional robustness of HCNs under various attacking strategies. Specifically, a heterogeneous network model is introduced to characterize HCNs considering different types of functional entities and information flows. Based on this setup, the rescaled operational capability index (ROCI) is first proposed to evaluate the functional robustness of HCNs, and the criterion for functional disintegration of HCNs is established by summing the values of ROCI during the attacking process. Finally, the reliability and effectiveness of HCNFR are illustrated with an empirical case study. The results provide useful insights for operational guidance and design of a more functional and robust combat system-of-systems.

Detecting nanometric displacements with optical ruler metrology.

We introduce the optical ruler, an electromagnetic analog of a physical ruler, for nanoscale displacement metrology. The optical ruler is a complex electromagnetic field in which singularities serve as the marks on the scale. It is created by the diffraction of light on a metasurface, with singularity marks then revealed by high-magnification interferometric observation. Using a Pancharatnam-Berry phase metasurface, we demonstrate a displacement resolving power of better than 1 nanometer (λ/800, where λ is the wavelength of light) at a wavelength of 800 nanometers. We argue that a resolving power of ~λ/4000, the typical size of an atom, may be achievable. An optical ruler with dimensions of only a few tens of micrometers offers applications in nanometrology, nanomonitoring, and nanofabrication, particularly in the demanding and confined environment of future smart manufacturing tools.

Analysis of GFRP insulator characteristics under multiphysical fields in electromagnetic rail launchers

The glass fiber-reinforced polymer (GFRP) insulators in electromagnetic rail launchers (EMRLs) work in a complex environment coupling electromagnetic, thermal and structural fields. Ablation, metal deposition, fracture and other destructive forms easily appear in GFRP insulators, which will affect the efficiency and service life of the electromagnetic launcher system. To explore the factors causing insulator performance degradation, a coupling model of multiphysical fields, including electromagnetism, temperature and structure, was established to analyze the physical load on the GFRP insulators in EMRLs. And based on the results of the coupling numerical analysis, delamination or fracture may occur in the middle of insulators. An insulator sample was experimentally analyzed after electromagnetic launch tests to verify the simulation conclusions and to obtain the failure mechanism of GFRP insulators under extreme environments of multiphysical fields. During electromagnetic launching, the rails repeatedly compress the GFRP insulators and cause cracking of the GFRP insulators. High temperature causes carbonization and metal contamination on the surface of the GFRP insulators, which results in a decrease in surface resistivity. In addition, there were pits on the surface of the GFRP insulators, possibly due to the armature planing against the GFRP insulators during electromagnetic launching.

KlyC: 1.5-D Large-Signal Simulation Code for Klystrons

The High Efficiency International Klystron Activity (HEIKA) was initiated at CERN in 2014 to evaluate and develop new klystron bunching technologies for high-efficiency klystrons in application to the large-scale scientific projects such as the Compact Linear Collider (CLIC) and the Future Circular Collider (FCC). The success of such development strongly depends on the availability of the specialized klystron computer codes. Unfortunately, the accurate and efficient 2-D large-signal codes are proprietary and are not freely available to the wide klystron community. The new 1.5-D klystron code called KlyC has been developed as an attempt to bridge the gap between fast, but approximate 1-D models and time/resources consuming particle-in-cell (PIC) codes. KlyC simulates the specific physical processes such as the current emission from the metal surface, the space charge depression along the klystron, and the residual RF current modulation of the spent beam. KlyC internal eigenmode solver allows fast simulations of the 2-D complex electromagnetic (EM) field in the axis-symmetrical cavity with the arbitrary cavity profile. The internal KlyC optimizer module can help the designer to speed up the klystron development process. In this paper, the theoretical model, general review of the code performance, and benchmarking between KlyC, AJDisk/1-D, PIC code MAGIC/2-D, and CST/3-D are presented using FCC klystrons as an example.

A design method of spatiotemporal optical pulse using level‐set based time domain topology optimization

SummaryRecently, two emerging areas of photonics research, ultrafast photonics, and nanophotonics have started to come together. One of the main problems in this field is the precise control of spatial and temporal profiles of the optical pulses. In this paper, we propose a design method for user‐specified spatiotemporal optical pulses using a level set‐based time‐domain topology optimization method. In the proposed method, the optimization problem is formulated based on time domain Maxwell equations so that the spatiotemporal optical pulses can be treated directly. The objective function is defined using the envelope information of the pulses, and an efficient way to calculate this information, based on calculations of the complex electromagnetic field, is introduced. A level set‐based topology optimization method is applied to obtain optimized configurations.Using the proposed method, the spatiotemporal user‐specified pulse profiles can be designed by modifying the structural details of the nanostructures through which the pulses propagate. As a simple example, we demonstrate that the optimized structures focus optical pulses into a single or multiple focal points with a user‐specified pulse‐width. The results show that the proposed method is able to design highly controlled spatiotemporal optical pulses by engineering the nanophotonic structure.

An EIGA driven coupled of electromagnetic-thermal field modeling in the induction melting process

A crucible-free, an Electrode Induction melting Gas Atomization (EIGA) technique for induction melting of the reactive and refractory metals/alloys is developed. The impedance matching of the superalloy Rene95 in a conical induction has been investigated. An evaluation of the complex electromagnetic and thermal fields on the free surface of the superalloy Rene95 is carried out by both numerical and experimental methods under alternating currents with the output power of 120 kW and operational effective current 2 kA. The two types of coupling induction coils have been devised, tested and compared with the experimental results, revealing the impedance of four-turn induction coil with superalloy Rene95 releasing the electrical energy that causes the most high-temperature distribution in the surface of superalloy Rene95. Induction coil is also known as an “inductor” which is the core component in the melting process of nickel-based superalloy, leading to design a good induction coil to reduce the power consumption and increase the efficiency of the process. The achievements are the melting rate enhancement and a steady-state of continuous liquid metal flow producing the liquid metal streams with diameter of about 5 mm.

Treatment of the breast cancer by using low frequency electromagnetic fields and Mn(II) complex of a Schiff base derived from the pyridoxal

The breast cancer is the most common type of cancer in women. In this project, the breast cancer was transplanted in vivo with the TUBO cells. Then, the cancerous mice were treated by radiation of low frequency electromagnetic fields and injection of the Mn(II) complex of the N,N′-dipyridoxyl(1,2-diaminobenzene) Schiff base. Three different concentrations of the Mn(II) complex were used. Cytotoxicity and morphological alterations caused by the Mn(II) complex in the TUBO breast cancer cell line have been evaluated. Apoptotic properties of the Mn(II) complex was studied using the flow cytometry. The Mn(II) complex has a cytotoxic effect on cancer cells. Also, both of the Mn(II) complex and low frequency electromagnetic field induced apoptosis, which was confirmed by flow cytometry. Both of them result in considerable changes in the treated tissues such as decrease of the tumor mass, induction of apoptosis and decrease in number of the blood vessels.

Intra-cycle depolarization of ultraintense laser pulses focused by off-axis parabolic mirrors

A study of the structure of the electric and magnetic fields of ultraintense laser pulses focused by an off-axis parabolic mirror is reported. At first, a theoretical model is laid out, whose final equations integration allows the space and time structure of the fields to be retrieved. The model is then employed to investigate the field patterns at different times within the optical cycle, for off-axis parabola parameters normally employed in the context of ultraintense laser–plasma interaction experiments. The results show that nontrivial, complex electromagnetic field patterns are observed at the time at which the electric and magnetic fields are supposed to vanish. The importance of this effect is then studied for different laser polarizations, $f$ numbers and off-axis angles.

Magnitude-phase Relationship behind Controlled-source Electromagnetic Field Revealed by Nyquist Diagrams

We present a means of processing data from frequency-domain controlled-source electromagnetic method observations via a Nyquist diagram. For a controlled-source electromagnetic field in the frequency domain, the x component of the electric field and the y and z components of the magnetic fields were chosen for discussion. Typical 1-D models and a 3-D model, which have a single anomalous body embedded in a half space, have been used to calculate the complex electromagnetic fields. The corresponding Nyquist diagrams have been plotted and analyzed. The diagrams can reveal the magnitude-phase frequency characteristics of an electromagnetic field and can be used to guide data processing by considering the constraints of the intrinsic connection between amplitude and phase. The results further show that: (1) the Nyquist diagrams of both electric and magnetic responses, varying from low to high frequencies, are all characterized by continuous, single-direction, clockwise spiral curves; (2) for the magnetic field, the opening direction of the Nyquist curve is upward for the y and downward for the z components, regardless of the change in resistivity; (3) for the electric fields, the resistivity changes also lead the spiral structure to take on complicated shapes, such as a snail-like shape or a W, and the starting points of the Nyquist curves depend on the variations in the resistivity with depth. According to the aforementioned rules, we can obtain reliable and reasonably complex field data during the data processing of frequency-domain controlled-source electromagnetic method, which lays a foundation for 3-D frequency-domain data inversion.

Effect of Electromagnetic Field in Hard Metal Technique

The publications of the effect of electric, magnetic, or complex electromagnetic fields applied in addition to well-known conventional processing of WC–Co powder composites are analyzed. Two types of composite processing are considered: conduction and induction heat treatment. The basic properties of equipment used by techniques for processing the above composites are studied based on the existing equipment. The effect of some features of the structure of materials on their properties is analyzed. A special attention is paid to structure defects, such as cracks and the continuity of brittle (WC) and ductile (Co) phases. Their effect on the strength, wear resistance, elasticity, fracture toughness, and other properties of hard metals is considered in details. This study provides a number of recommendations for eliminating or minimizing the impact of defects on the structure and properties of powder composites.

Kassiopeia: a modern, extensible C++ particle tracking package

The Kassiopeia particle tracking framework is an object-oriented software package using modern C++ techniques, written originally to meet the needs of the KATRIN collaboration. Kassiopeia features a new algorithmic paradigm for particle tracking simulations which targets experiments containing complex geometries and electromagnetic fields, with high priority put on calculation efficiency, customizability, extensibility, and ease-of-use for novice programmers. To solve Kassiopeia's target physics problem the software is capable of simulating particle trajectories governed by arbitrarily complex differential equations of motion, continuous physics processes that may in part be modeled as terms perturbing that equation of motion, stochastic processes that occur in flight such as bulk scattering and decay, and stochastic surface processes occurring at interfaces, including transmission and reflection effects. This entire set of computations takes place against the backdrop of a rich geometry package which serves a variety of roles, including initialization of electromagnetic field simulations and the support of state-dependent algorithm-swapping and behavioral changes as a particle’s state evolves. Thanks to the very general approach taken by Kassiopeia it can be used by other experiments facing similar challenges when calculating particle trajectories in electromagnetic fields. It is publicly available at https://github.com/KATRIN-Experiment/Kassiopeia.

PENTrack—a simulation tool for ultracold neutrons, protons, and electrons in complex electromagnetic fields and geometries

Modern precision experiments trapping low-energy particles require detailed simulations of particle trajectories and spin precession to determine systematic measurement limitations and apparatus deficiencies. We developed PENTrack, a tool that allows to simulate trajectories of ultracold neutrons and their decay products—protons and electrons—and the precession of their spins in complex geometries and electromagnetic fields. The interaction of ultracold neutrons with matter is implemented with the Fermi-potential formalism and diffuse scattering using Lambert and microroughness models. The results of several benchmark simulations agree with STARucn v1.2, uncovered several flaws in Geant4 v10.2.2, and agree with experimental data. Experiment geometry and electromagnetic fields can be imported from commercial computer-aided-design and finite-element software. All simulation parameters are defined in simple text files allowing quick changes. The simulation code is written in C++ and is freely available at github.com/wschreyer/PENTrack.git.

Numerical Investigation of Plasma Sheath Under Multiple Oscillations in Acceleration Region of Hall Thrusters

Oscillations range from KHz-GHz have been measured in the experimental measurements within the laboratory Hall thruster. With the various frequency oscillations, different kinds of collisions between particles and the complex electromagnetic field environment, the dynamics of particles in the discharge chamber are really intricate. The dynamics of particles become even untraceable in the near-wall region where the plasma sheath exists. In this study, the two-dimensional fully kinetic Immersed Finite Element Particle-In-Cell (IFE-PIC) numerical models are developed in the axial-radial (z-r) plane at the acceleration region, with the intent of examining the effects of multiple oscillations on the plasma sheath. The results are valuable for understanding the features of plasma sheath in acceleration region at the real working conditions.

Exploiting Optical Asymmetry for Controlled Guiding of Particles with Light

Conventional methods of manipulating particles with light, such as optical tweezers and optical tractor beams, rely on beam-shaping to realize complex electromagnetic field profiles and are thus sensitive to scattering. Here, we show that, by introducing tailored optical asymmetry in the particle, we can realize a novel guiding method that is controllable by the frequency of light, without regard to the direction or the shape of the light beam. With detailed stochastic simulations, we demonstrate guiding of a two-faced nanoparticle where the optically induced thermophoretic drift serves as the propulsion mechanism. Exploiting the difference in resonant absorption spectra of the two materials, we create a bidirectional local thermal gradient that is externally switchable. This is advantageous because the frequency of a light beam, unlike its shape or coherence, is preserved even in strongly scattering environments. Since this approach is insensitive to scattering and applicable to many particles at once, a...

Euclidean Complex Relativistic Mechanics: A New Special Relativity Theory

Relativity Theory (RT) was fundamental for the development of Quantum Mechanics (QMs). Special Relativity (SR), as is applied until now, cancels the transitive attribute in parallelism, when three observers are related, because Lorentz Boost (LB) is not closed transformation. In this presentation, considering Linear Spacetime Transformation (LSTT), we demand the maintenance of Minkowski Spacetime Interval (S2). In addition, we demand this LSTT to be closed, so there is no need for axes rotation. The solution is the Vossos Matrix (ΛB) containing real and imaginary numbers. As a result, space becomes complex, but time remains real. Thus, the transitive attribute in parallelism, which is equivalent to the Euclidean Request (ER), is also valid for moving observers. Choosing real spacetime for the unmoved observer (O), all the natural sizes are real, too. Using Vossos Transformation (VT) for moving observers, the four-vectors’ zeroth component (such as energy) is real, in contrast with spatial components that are complex, but their norm is real. It is proved that moving (relative to O) human O' meter length, according to Lorentz Boost (LB). In addition, we find Rotation Matrix Vossos-Lorentz (RBL) that turns natural sizes’ complex components to real. We also prove that Speed of Light in Vacuum (c) is invariant, when complex components are used and VT is closed for three sequential observers. After, we find out the connection between two moving (relative to O) observers: X"= ΛLO"(o) ΛLO(O') X', using Lorentz Matrix (ΛL). We applied this theory, finding relations between natural sizes, that are the same as these extracted by Classic Relativity (CR), when two observers are related (i.e. relativistic Doppler shift is the same). But, the results are different, when more than two observers are related. VT of Electromagnetic Tensor (Fμv), leads to Complex Electromagnetic Fields (CEMFs) for a moving observer. When the unmoved observer O and a moving observer O' are related, O measures the same Real Electromagnetic Fields (REMFs) as those are given, using LB, but O' measure CEMFs with the same formula. Complex Electromagnetic Tensor (F'B) turns to Real Electromagnetic Tensor (F') using the formula . When there are two moving (relative to O) observers O' and O", their real electromagnetic tensors are related, using the form F" = ΛLO"(O) ΛLO(O) F' [ΛLO"(O') ΛLO(O')]T. In addition, we prove that the relation between two moving (relative to O) observers, when they use Real Coordinates (RCs), causes a real rotation between their frames. The turn is opposite to the turn of Thomas and has a little different measure, when the velocities are small. We apply these to the Uniform Circular Motion (UCM) and to the Hydrogen Atom (H), considering that the Proton (p) is the unmoved observer O and the laboratory observer O' has infinitesimal velocity. Using Perturbation Theory (PT) we calculate the position of the fine structure peaks of the atomic spectrum. The result is better not only than this extracted using P. Dirac Theory, but also than that extracted using L. H. Thomas Method.

Occupational exposure of personnel operating military radio equipment: measurements and simulation

Technical literature provides numerous studies concerning radiofrequency exposure measurements for various radio communication devices, but there are few studies related to exposure of personnel operating military radio equipment. In order to evaluate exposure and identify cases when safety requirements are not entirely met, both measurements and simulations are needed for accurate results. Moreover, given the technical characteristics of the radio devices used in the military, personnel mainly operate in the near-field region so both measurements and simulation becomes more complex. Measurements were made in situ using a broadband personal exposimeter equipped with two isotropic probes for both electric and magnetic components of the field. The experiment was designed for three different operating frequencies of the same radio equipment, while simulations were made in FEKO software using hybrid numerical methods to solve complex electromagnetic field problems. The paper aims to discuss the comparative results of the measurements and simulation, as well as comparing them to reference levels specified in military or civilian radiofrequency exposure standards.

The Pauli–Lubański vector, complex electrodynamics, and photon helicity

We critically analyze the concept of photon helicity and its connection with the Pauli–Lubański vector from the viewpoint of the complex electromagnetic field, sometimes attributed to Riemann but studied by Weber, Silberstein, and Minkowski. To this end, a complex covariant form of Maxwell’s equations is used. Weyl’s two-component wave equation for massless neutrinos is also briefly discussed.

Analytical tools for investigating strong-field QED processes in tightly focused laser fields

The present paper is the natural continuation of the letter [Phys. Rev. Lett. \textbf{113}, 040402 (2014)], where the electron wave functions in the presence of a background electromagnetic field of general space-time structure have been constructed analytically, assuming that the initial energy of the electron is the largest dynamical energy scale in the problem and having in mind the case of a background tightly focused laser beam. Here, we determine the scalar and the spinor propagators under the same approximations, which are useful tools for calculating, e.g., total probabilities of processes occurring in such complex electromagnetic fields. In addition, we also present a simpler and more general expression of the electron wave functions found in [Phys. Rev. Lett. \textbf{113}, 040402 (2014)] and we indicate a substitution rule to obtain them starting from the well-known Volkov wave functions in a plane-wave field.

Attitude estimation and three-axis magnetometer on-line calibration based on moving horizon estimation

According to the attitude estimation and three-axis magnetometer on-line calibration, a real time moving horizon estimation algorithm is presented in this paper. First, moving horizon estimation filter is designed since system constraints existing in most practical cases cannot be solved analytically in the framework of Kalman filter. Taking advantage of the optimal problem in dealing with constraints, the presented method converts the attitude estimation problem into an optimal one by which the quaternion normalization property can be solved analytically in smaller searching space with better efficiency and accuracy. Second, through a series of linearization of system equations, Gauss-Newton iterative method is applied in the horizon window composed of finite history information to obtain the best state estimation and meet the real time requirement at the same time. Once the newest best state estimation value is obtained, it will be sacked into the horizon window and the oldest one discarded. By this way, the filter is moving forward. Finally, based on the proposed method, the three-axis magnetometer parameter on-line calibration combined with attitude estimation is solved without adding any system state dimension, which can also make sure that the measurements with three-axis magnetometer are in the form of vector as its obvious benefits in the sense of ensuring information quantity. On considering the extreme environment such as great temperature gradient, mechanical pressure and complex electromagnetic fields, different from that of the off-line calibration, the calibration parameter is changed definitely. So the on-line calibration is necessary though neglected by most papers. Simulation results show that under the condition of small initial errors, the difference of accuracy among EKF, UKF and moving horizon estimation is small. But the computational burden of the last one is relatively large. The advantage of the described method is not so obvious in this case. But when the initial errors are large, the moving horizon estimation still can get the precise results no matter how great are the EKF (extended Kalman filter) and UKF (unscented Kalman filter) deviated from the true values. Thus the proposed method has its high accuracy and poor sensitivity of the initial and systematic errors along with fast convergence, all of which are vital in most actual environments.