Frequency Of Field Research Articles

Study of mechanical and electrical properties through positron annihilation spectroscopy for ethylene-propylene-diene rubber biocomposites with treated wheat husk fibers

The positron annihilation lifetime (PAL) spectroscopy characteristics of ethylene-propylene-diene monomer rubber (EPDM) composites reinforced with treated wheat husk fibers (WHFs) were investigated for the first time. PAL spectroscopy is employed to study the free volume of polymers. The use of lignocellulosic materials as reinforcement in polymeric composites has gained attention due to their low cost, availability, and eco-friendliness. In this study, the impact of the loading concentration on the interfacial adhesion between the EPDM matrix and WHFs is quantified, along with the evaluation of swelling measurement and tensile properties. Additionally, the nanoscopic properties derived from PAL spectroscopy correlate with the composites’ macroscopic properties. In addition, the dielectric properties of the investigated samples have been studied, and their conductivity has been calculated. To determine the conduction mechanism within these samples and how it is affected by the addition of WHF, the change in electrical conductivity with the frequency of the external electric field applied to the samples was studied, and from this, the conduction mechanism was determined, and the barrier height value was calculated. The experimental results provide insights into the relationship between the structure and properties of EPDM-WHF biocomposites, offering valuable knowledge for developing sustainable and high-performance materials.

Terahertz Crystal-Field Transitions and Quasi Ferromagnetic Magnon Excitations in a Noncollinear Magnet for Hybrid Spin-Wave Computation.

The complexity of interactions between the crystal-field and unusual noncollinear spin arrangement in nontrivial magnets demands novel tools to unravel the mystery underneath. In this work, we study such interaction dynamics of crystal-field excitations (CFE) and low-energy magnetic excitations in orthochromite TmCrO3 with controls of temperature and magnetic field using high-resolution magneto-terahertz (THz) time-domain spectroscopy. The THz energy spectrum spanning 0.5-10 meV possesses a low-frequency spin-excitation (magnon) mode and a multitude of CFE modes at 10 K, all of which uniquely embody a range of phenomena. For the magnon mode, a temperature dependence of peak frequency is induced by magnetic interactions between Tm and Cr subsystems. While a change from blue to red shift of peak frequency of this mode marks the magnetization reversal transition, the spin-reorientation temperature and change of magnetic anisotropy are depicted by different features of field and temperature dependent peak frequency dynamics. The modes corresponding to CFE are robust and laden with a multitude of submodes, which are attributes of nontrivial interactions across different transitions. These modes are suppressed only upon substitution of Tb3+ at the Tm3+ site, which suggests a dominant role of single-ion anisotropy in controlling entire THz excitation spectra. Overall, this remarkable range of phenomena seen through the unique lens of all-optical THz tools provides deeper insights into the origin of magnetic phases in systems with complex interactions between rare-earth and transition metal ions and provides a multitude of novel combinations of closely spaced modes for emerging hybrid spin-wave computation.

Giant lateral shift in single mode cavity containing four-level sodium atomic medium

Abstract In this paper, a four-level sodium atomic medium coupled to a single-mode cavity is used to investigate the Goos-Ha¨nchen (GH) shift. Using the collective phase of the control fields and intensity of Rabi oscillation, the positive as well as negative GH-shift in transmission and reflection beams are examined. In the transmission beam, a maximum GH-shift of ±6λ is observed. Furthermore, GH-shift in both reflection and transmission beams in a four-level sodium atomic medium is significantly enhanced by photon number density as well as by the cavity coupling strength. By varying the collective phase of the control fields and the probe field frequency, GH-shift in reflection exhibits a maximum value of ±2λ. Our findings may open up significant applications in micro-optics, sensors, photonic crystals and nano-processor technology.

Frequency-Dependent Antioxidant Responses in HT-1080 Human Fibrosarcoma Cells Exposed to Weak Radio Frequency Fields.

This study explores the complex relationship between radio frequency (RF) exposure and cancer cells, focusing on the HT-1080 human fibrosarcoma cell line. We investigated the modulation of reactive oxygen species (ROS) and key antioxidant enzymes, including superoxide dismutase (SOD), peroxidase, and glutathione (GSH), as well as mitochondrial superoxide levels and cell viability. Exposure to RF fields in the 2-5 MHz range at very weak intensities (20 nT) over 4 days resulted in distinct, frequency-specific cellular effects. Significant increases in SOD and GSH levels were observed at 4 and 4.5 MHz, accompanied by reduced mitochondrial superoxide levels and enhanced cell viability, suggesting improved mitochondrial function. In contrast, lower frequencies like 2.5 MHz induced oxidative stress, evidenced by GSH depletion and increased mitochondrial superoxide levels. The findings demonstrate that cancer cells exhibit frequency-specific sensitivity to RF fields even at intensities significantly below current safety standards, highlighting the need to reassess exposure limits. Additionally, our analysis of the radical pair mechanism (RPM) offers deeper insight into RF-induced cellular responses. The modulation of ROS and antioxidant enzyme activities is significant for cancer treatment and has broader implications for age-related diseases, where oxidative stress is a central factor in cellular degeneration. The findings propose that RF fields may serve as a therapeutic tool to selectively modulate oxidative stress and mitochondrial function in cancer cells, with antioxidants playing a key role in mitigating potential adverse effects.

The state of the hypothalamic-pituitary-adrenal system in workers exposed to electric and magnetic fields of industrial frequenc

Introduction. Electric and magnetic fields of industrial frequency are an integral part of production processes, and their effect on the human body is of increasing interest both among scientists and among specialists in the field of medicine and occupational safety. In recent decades, there has been growing concern about the potential impact of these areas on the health of workers, especially those who are exposed to prolonged exposure in the course of their professional activities. In this context, we pay special attention to the neuroendocrine system, which plays a key role in regulating many physiological processes, including metabolism, stress reactions and maintaining homeostasis. The study of the fundamentals of the neuroendocrine system and the mechanisms of the effect of electromagnetic fields on the body not only contributes to the deepening of scientific knowledge in the field of biomedical research, but also has practical significance in ensuring occupational safety and improving working conditions in industrial enterprises, allowing to identify possible health consequences and develop effective measures to protect workers from negative bioeffects. The study aims to research the effects of electric and magnetic fields of industrial frequency on the functional state of the hypothalamic-pituitary-adrenal system of employees of electric grid facilities. Materials and methods. Specialists examined 144 employees of the main group engaged in the repair and operation of electric grid facilities and 40 employees of the control group who were not exposed to electromagnetic fields of industrial frequency. We determined the concentration of adrenocorticotropic hormone, cortisol and dehydroepiandrosterone sulfate in blood serum samples and calculated the ratio of dehydroepiandrosterone sulfate to cortisol. Results. Workers exposed to the combined effects of electric and magnetic fields of industrial frequency had a lower (p<0.05) level of adrenocorticotropic hormone (1.9 [0.5; 3.9] pg/ml) and dehydroepiandrosterone sulfate (5.8 [3.7; 8.4] mmol/l) in the blood compared with the group of workers exposed to magnetic fields industrial frequency fields (4.4 [2.1; 12.9] pg/ml; 9.8 [6.3; 14.5] mmol/l) and to the control group (6.4 [4.0; 19.8] pg/ml; 7.8 [4.7; 13.3] mmol/l), respectively. The scientists also revealed in the group of workers exposed to combined exposure in the field, the association of a low ratio of dehydroepiandrosterone sulfate and cortisol with the development of cardiovascular diseases and feedback from work experience (p<0.05). Limitations. The study is limited by the number of people surveyed (144 employees). Conclusion. The results of the study indicate the hypoactivity of the hypothalamic-pituitary-adrenal system induced by exposure to electric and magnetic fields of industrial frequency, manifested by a decrease in the level of adrenocorticotropic hormone, dehydroepiandrosterone sulfate and its relationship to cortisol in workers exposed to combined effects of electric and magnetic fields of industrial frequency. Ethics. The work complies with ethical standards developed in accordance with the Helsinki Declaration of the World Medical Association "Ethical Principles of conducting Scientific medical research with human participation" as amended in 2000 and the "Rules of Clinical Practice in the Russian Federation" approved by Order of the Ministry of Health of the Russian Federation dated 04/01/2016 No. 200n. We received informed consent from each examined person to participate in the study, approved in accordance with the established procedure by the local Ethics Committee of Izmerov Research Institute of Occupational Health (minutes of the meeting of the Ethics Committee No. 17 dated 12/16/2015).

Chitosan solutions and films properties obtained using electromagnetic-activated water

Purpose of research: to obtain chitosan films with improved performance properties by using water activated by an electromagnetic field of the radio frequency range as a solvent. Objects of research: water activated by an electromagnetic field of the radio frequency range (90-200 MHz), as well as chitosan solutions and films obtained using it. Methods of research: conductometry, potentiometry, densitometry, viscometry, turbidimetry, gravimetry, IR spectroscopy are used in the work. To determine the deformation and strength characteristics of the films, a universal testing machine with an electromechanical drive УТС-110M was used. Main results of research: The effect of pretreatment of water with an electromagnetic field of various frequencies on the properties of acetic acid (2 %) chitosan solutions in the concentration range of 0.1-2.0% has been studied. A decrease in surface tension by 2.0–5.2 % was found, as well as an increase in light transmission by 10-30 % and viscosity of solutions by 24-37 % at a chitosan concentration of 1.0-2.0 %. These effects are most pronounced for frequencies of 70, 90, 110 and 130 MHz. Films were prepared from 2 % chitosan solutions and their deformation-strength and sorption characteristics with respect to water vapor were determined. The greatest increase in tensile strength was found for chitosan films obtained from solutions prepared on water activated by an electromagnetic field with frequencies of 70 and 110 MHz (38 and 23 %, respectively). A decrease in the hygroscopicity of films and an increase in the intensity of bands in the IR spectra of films obtained using activated water were found.

Exceptional points in the microcavity with phonon pump enhance the transparency and slow light

We theoretically investigated optomechanically induced transparency (OMIT) and slow light in a microcavity optomechanical system containing three nanoparticles, where the pump-probe field drives the cavity and a weak phonon pump drives the mechanical resonator. When the phonon pump frequency matches the pump-probe field frequency difference, adjusting the phonon pump's amplitude and phase can result in the transparency window exceeding unity. Tuning the relative positions of nanoparticles can periodically steer the system to exceptional points (EPs), further enhancing and modulating the transparency window. Furthermore, the phonon pump causes the phase dispersion at the transparency window to become highly steep, resulting in a large value and tunable group delay. Notably, when the system is at EPs, the slow light can be enhanced by approximately two times compared to when the system is not at EPs. Our research demonstrates a way to control optical transmission with potential applications in quantum communications and optical buffers.

Characterization of AI-enhanced magnetophoretic transistors operating in a tri-axial magnetic field for on-chip bioparticle sorting.

We demonstrate two general classes of magnetophoretic transistors, called the "trap" and the "repel-and-collect" transistors, capable of switching single magnetically labeled cells and magnetic particles between different paths in a microfluidic chamber. Compared with prior work on magnetophoretic transistors operating in a two-dimensional in-plane rotating field, the use of a tri-axial magnetic field has the fundamental advantages of preventing particle cluster formation and better syncing of single particles with the general operating clock. We use finite element methods to investigate the energy distribution on the chip surface and to predict the particle behavior at various device geometries. We then fabricate the proposed transistors and compare the experimental results with the simulation predictions. We found that with gate electrical currents of ~ 40mA for a transistor with proper geometry, complete switching of magnetic particles with diameters in the range of 8-15μm is achieved. We show that the device is reliable and works well at different magnetic field strengths (50-100 Oe) and frequencies (0.05-0.5Hz). We also employed an image processing code with a trained convolutional neural network to automate the proposed transistors for identifying and sorting particles with various sizes and magnetic susceptibilities with accuracies higher than 98%. The proposed transistors can be used in designing novel magnetophoretic circuits for important applications in biomedical microdevices and single-cell biology.

Roadmap on basic research needs for laser technology

Abstract Motivated by the profound impact of laser technology on science, arising from an increase in focused light intensity by seven orders of magnitude and flashes so short electron motion is visible, this roadmap outlines the paths forward in laser technology to enable the next generation of science and applications. Despite remarkable progress, the field confronts challenges in developing compact, high-power sources, enhancing scalability and efficiency, and ensuring safety standards. Future research endeavors aim to revolutionize laser power, energy, repetition rate and precision control; to transform mid-infrared sources; to revolutionize approaches to field control and frequency conversion. These require reinvention of materials and optics to enable intense laser science and interdisciplinary collaboration. The roadmap underscores the dynamic nature of laser technology and its potential to address global challenges, propelling progress and fostering sustainable development. Ultimately, advancements in laser technology hold promise to revolutionize myriad applications, heralding a future defined by innovation, efficiency, and sustainability.

Extracorporeal Magnetotransduction Therapy as a New Form of Electromagnetic Wave Therapy: From Gene Upregulation to Accelerated Matrix Mineralization in Bone Healing.

Electromagnetic field therapy is gaining attention for its potential in treating bone disorders, with Extracorporeal Magnetotransduction Therapy (EMTT) emerging as an innovative approach. EMTT offers a higher oscillation frequency and magnetic field strength compared to traditional Pulsed Electromagnetic Field (PEMF) therapy, showing promise in enhancing fracture healing and non-union recovery. However, the mechanisms underlying these effects remain unclear. This study demonstrates that EMTT significantly enhances osteoblast bone formation at multiple levels, from gene expression to extracellular matrix mineralization. Key osteoblastogenesis regulators, including SP7 and RUNX2, and bone-related genes such as COL1A1, ALPL, and BGLAP, were upregulated, with expression levels surpassing those of the control group by over sevenfold (p < 0.001). Enhanced collagen synthesis and mineralization were confirmed by von Kossa and Alizarin Red staining, indicating increased calcium and phosphate deposition. Additionally, calcium imaging revealed heightened calcium influx, suggesting a cellular mechanism for EMTT's osteogenic effects. Importantly, EMTT did not compromise cell viability, as confirmed by live/dead staining and WST-1 assays. This study is the first to show that EMTT can enhance all phases of osteoblastogenesis and improve the production of critical mineralization components, offering potential clinical applications in accelerating fracture healing, treating osteonecrosis, and enhancing implant osseointegration.

Investigating the Effects of Induction Heating on a Submerged Hollow Cylindrical Element

ABSTRACTThis article proposes an induction heating element that addresses heat transfer and thermal homogenization while being fully submerged in a liquid, specifically focusing on heating of water as a case study. The design calculations, fabrication, and realization of a resonant induction heating system that heats the proposed heating element are presented. The geometric shape of proposed heating element is a hollow cylinder that maintains structural strength while delivering required thermal energy because of an external time‐varying magnetic field. Detailed mathematical modeling of the proposed heating element's equivalent electric circuit has been presented while considering physical parameters including diameter, thickness, height, material properties, magnetic field frequency, and skin effect. A laboratory scale prototype of the induction heating system including the proposed heating element has been built, and experiments have been demonstrated. The experimental results of the working induction heating resonant inverter and RLC resonant circuit inductance and capacitance with induction load are presented. Additionally, the results of thermographic images and temperature–time profile of the water sample, which was heated using the proposed heating element, are provided to demonstrate the heating element's reliability and practicality. This research contributes to the field of induction heating technology by investigating a heating element that is submerged in a liquid medium, resulting in a uniform temperature distribution throughout the liquid. The conventional method of heating water in a stainless steel cup‐shaped container is an inefficient heat transfer process. In stainless steel cup‐shaped containers, a portion of the energy input used to boil the water is lost to the environment through the surface area of the container that is not in direct contact with the water. This heat loss occurs due to the container's design, which exposes a large surface area to the surrounding environment, allowing thermal energy to dissipate through conduction, convection, and radiation.

Effect of Magnetic Field and Magnetic Nanoparticles on Choice of Endothelial Cell Phenotype

Background. Endothelial cells as participants in angiogenesis choose their phenotype as tip cells (leading, migratory) or stalk cells (following). It has been experimentally found and theoretically modeled that rapid oscillations in intracellular calcium concentration play a key role in controlling phenotype selection and possible vessel architecture. In addition, the intracellular calcium concentration in endothelial cells is known to be regulated by mechanical wall shear stress induced by blood flow, which controls mechanosensitive calcium ion channel gating. Experimental methods of controlling mechanosensitive ion channel gating in external magnetic fields with application of magnetic nanoparticles are developed that affect magnetic nanoparticles artificially attached to cell membranes. Objective. A key question is raised about the possibility of controlled selection of endothelial cell phenotype in external magnetic fields due to the presence of artificial or biogenic magnetic nanoparticles embedded in the cell membrane. Methods. The magnetic wall shear stress is calculated due to the influence of the external magnetic field on the magnetic nanoparticles embedded in the cell membrane, which controls the mechanosensitive calcium ion pathways. Numerical modeling of oscillations in intracellular calcium concentration in endothelial cells and determination of their final phenotype was carried out taking into account intercellular communication. The python programming language and scipy, py-pde, matplotlib packages of the python programming language were used for numerical modeling. Results. The magnetic field flux density and frequency ranges of a uniform rotating magnetic field, as well as the magnitude of the gradient and the frequency of a non-uniform oscillating magnetic field were calculated for controlling the amplitude and frequency of intracellular calcium concentration oscillations in endothelial cells, as well as the selection of their phenotype. It opens the perspective of controlling angiogenesis and vessel architecture. Conclusions. Phenotype selection by endothelial cells can be controlled in a uniform rotating external magnetic field, as well as in a non-homogeneous oscillating magnetic field.

Ferroelectric tungsten bronze-based ceramics with high-energy storage performance via weakly coupled relaxor design and grain boundary optimization

A multiscale regulation strategy has been demonstrated for synthetic energy storage enhancement in a tetragonal tungsten bronze structure ferroelectric. Grain refining and second-phase precipitation (perovskite phase) are introduced in the BaSrTiNb2-xTaxO9 ceramics by regulating the composition and sintering process. Disordered polarization and distribution, chemical inhomogeneity, and insulating boundary layers are achieved to provide the fundamental structural origin of the relaxation characteristic, high breakdown strength, and superior energy storage performance. Thus, an ultrahigh energy storage density of 12.2 J cm−3 with an low energy consumption was achieved at an electric field of 950 kV cm−1. This is the highest known energy storage performance in tetragonal tungsten bronze-based ferroelectric. Notably, this ceramic shows remarkable stability over frequency, temperature, and cycling electric fields. This work brings new material candidates and structure design for developing of energy storage capacitors apart from the predominant perovskite ferroelectric ceramics.

Characterization of the scattered pressure from a cylindrical shell close to a free surface and understanding of the depth-dependent phenomenon

The characterization of the scattered pressure field of a submerged cylindrical target is of interest for underwater acoustics applications. The aim of this work is to study the vibroacoustic behavior of an immersed cylindrical shell excited by a plane wave, particularly in close proximity to a free surface. To achieve this goad, finite element simulation and experimental investigation are carried out on a mock-up. The effect of the free surface is highlighted by comparing results to those obtained in a free field situation, in both time and frequency domains. Additional echoes are observed on the time signals due to the presence of the free surface. In fact, after being scattered by the target, these echoes reflect on the surface, implying a time shift between echoes directly from the target and those that have travelled a longer path. The spectrum is also impacted as the form function shows additional oscillations. These observations are depth-dependent. To determine wave trajectories, a study based on flight time and ray theory is conducted.

Thermoelectroluminescence in Anthracene and Anthracene Doped With Acridine Phosphors

AbstractIn the present study, an effort is made to record the thermoelectroluminescence (TEL) glow curves and electroluminescence (EL) spectra for anthracene, acridine, and anthracene doped with acridine to determine the trap depth and escape frequency in these materials. For recording the TEL glow curves, the EL cell is heated at the study rate after 500 Vrms (RMS) of AC is supplied between the plates. At various field frequencies, the light output is recorded. To comprehend the luminescence processes and mechanisms in these films, three methods have been employed to determine the trap energy and escape frequency.

Study on the acoustic disturbance characteristics of the spray flame

The axial sound field was added to the ethanol spray flame as a perturbation element to study the dynamic response and combustion characteristics. A forced acoustic field is applied to a small oscillating flame. In cases where the frequency of the external sound field matches the eigenfrequency, even small amplitude self-excited flames demonstrate significant instability. As the intensity of the sound field increases, the amplitude of pressure oscillations sharply rises, and the pressure and flame heat release oscillations are in-phase. When the sound field operates at frequencies other than the eigenfrequency, it has an inhibitory effect on the evaporation and combustion process of ethanol droplets. Consequently, intensifying the sound field leads to a reduction in both the area of the evaporation combustion zone and the axial temperature of the flame. The CO formation is influenced by both temperature and the sound field, showing a pattern of increasing and then decreasing with the increase of sound intensity. Additionally, NOx generation exhibits higher emission concentrations in low-temperature and short flames, which is more likely to prompt NOx and is not closely related to frequency.

“Nutation” of electron spins in biradicals

In this work, the nutation of the spins of unpaired electrons in the nitroxide biradical of bis‑methano[60]fullerene was experimentally studied. Nutation frequencies were found in a wide range of microwave field power. To interpret the obtained results, numerical calculations of the nutation of biradicals were carried out for a set of parameters of the spin–spin interaction of a pair of unpaired electrons and for different values of the Rabi frequency of the microwave field. At comparing numerical results with experimental data, we also used the results of analytical calculations of nutation for some model situations. As a result of the analysis of experimental data on nutation, an estimate of the exchange and dipole–dipole interactions for the studied biradical was obtained. They are consistent with the results obtained from analysis of the shape of the EPR spectrum for a given biradical.

Electron acceleration by stochastic wave fields in a bounded plasma system

We investigate the electron acceleration dynamics in spatially stochastic wave fields. For a bounded system, the spectra (frequency and wave number) of the stochastic wave fields are discrete so that they can form spatiotemporal “singular” structures once their phases are in synchronization. As a consequence, the electrons will experience significant scattering by these singular structures, which is an in-phase effect of an ensemble of non-resonant wave–particle interactions. In the presence of parallel symmetry breaking, it is found that the governing Fokker–Planck equation has a structure similar to that of the resonant wave–particle interaction but with a broader parameter regime in the velocity/energy space of the electron distribution function.

Iron wool as a heating agent for magnetic catalysis: Experiments and analysis of heating properties under a high-frequency magnetic field

Magnetically induced heterogeneous catalysis has been attracting attention due to its high energy efficiency and flexibility for dynamic reactor control. Iron wool is a commercial, low-cost, and versatile heating agent, which has been used in several magnetic catalysis studies, but its heating properties have never been investigated. Here, the properties of three types of Fe wool were studied using optical and electronic microscopy, x-ray diffraction, and measurements of both heating power and high-frequency hysteresis loops. The effects of strand width, packing, and magnetic field amplitude and frequency were studied. A maximum specific absorption rate (SAR) around 700 W/g under a rms field of 47.4 mT at 93 kHz was measured for the larger width Fe wool. High-frequency hysteresis loops were used to quantify the contribution of hysteresis losses and eddy currents to total heating. Eddy currents contribute 65%–90% to the global heating depending on the strand width. Coating the wool with SiO2 and Ni has negative effects on the SAR but none on hysteresis losses. It is interpreted as originating from the cut-off of inter-wire eddy currents due to the insulating (SiO2, oxidized Ni) nature of the coating. Last, it was found that adding more Fe wool in a given volume mostly decreases the SAR. This effect could be not only due to the absorption and/or screening of the field by surface strands but also due to magnetic interactions. The results described in this work give insights into the magnetic heating of microscale magnetic materials and optimize their use for heterogeneous catalysis.

Regionalization, Decomposition, and Information Mining for Precipitation: A Novel Framework Based on Multivariate SOM Clustering and Multiscale Features

Abstract Precipitation regionalization, serving as a foundation for extrapolating information from gauged to ungauged sites, contributes to a comprehensive understanding of the spatial distribution of precipitation. However, existing studies have focused mainly on precipitation, neglecting the influence of climate background and meteorological circulation. Moreover, there is a lack of specialized analysis of regionalization results. This study proposes a novel approach to precipitation regionalization that considers covariates in the circulation field and periodic features. The method utilizes Barnett–Preisendorfer canonical correlation analysis coupled with principal component analysis (BPCCA) to select covariates and multivariate self-organizing map (SOM) clustering for preliminary regionalization. Wavelet decomposition is further used for regional feature analysis. The methodology is empirically applied to analyze summer precipitation in Shanxi Province, identifying homogeneous regions characterized by diverse spatiotemporal distributions. The results successfully identified 12 distinct regions of precipitation, effectively capturing the influence of topographic and atmospheric factors. According to the periodic and trend characteristics of each region at different time scales, we merged the division results on the three frequencies and six regions were ultimately differentiated. Specifically, a decreasing trend was observed in the southern and southeastern parts of Shanxi, as well as in the western part of the Lüliang Mountains. They had a significant 4-yr period mode, and the decreasing trend was more significant in the southern region. In contrast, northern Shanxi showed no trend and a significant 8-yr period mode. This proposed method presents an effective strategy for enhancing precipitation regionalization and extracting valuable information from the circulation field and multiple frequencies.