Electrical Relaxation Research Articles

Design of a Low-Cost PMMA/PVAc/PANI Blended Polymers: Structural, Electrical and Dielectric Characteristics

Abstract Polymethyl methacrylate (PMMA)/ polyvinyl acetate (PVAc)/ tetra-n-butylammonium iodide (TBAI)/ x wt % polyaniline (PANI) blended polymers are fabricated using the casting method to operate in energy storage purposes. The structure and morphology of the created blends were studied using X-ray diffraction (XRD) and scanning electron microscope (SEM) techniques. XRD analysis displayed that the semicrystalline behavior of the polymer blend is unaffected by doping. At 293 K and 100 Hz, the dielectric constant decreased from 22.7 (undoped) to 14.04-21.7 depended on the amount of PANI in the doped blend. The greatest energy density (U) values were reported in the blend with x=0.33; U=0.00469 J/m3 at 293 K and 100Hz. Increasing the temperature also improves the U values for all blends. The U values of the doped blends with x=0.11, 0.22, and 0.33 showed an impressive rise relative to the undoped blend. In the low and intermediate frequency ranges, the ac conductivity increased in the blend with x=0.44. The correlated barrier hopping (CBH) model was used to describe the electric mechanism of all blends. The influence of the quantity of PANI doping and temperature on electrical impedance spectroscopy, electric modulus, and relaxation time was investigated.

The Study of Electrical Conductivity and Dielectric Relaxation in the Organic Ferroelectric Diisopropylammonium Iodide (dipaI)

The Study of Electrical Conductivity and Dielectric Relaxation in the Organic Ferroelectric Diisopropylammonium Iodide (dipaI)

Beyond Painkillers: A Meta-Analysis of Non-Pharmacological Approaches for Managing Dysmenorrhea Symptoms

Dysmenorrhea, commonly known as painful menstruation, is a highly prevalent gynecological condition affecting millions of women globally. While pharmacological interventions offer temporary relief, they often come with undesirable side effects. Non-pharmacological approaches present a potentially safer and more sustainable alternative for managing dysmenorrhea symptoms. A comprehensive search of electronic databases, including PubMed, Scopus, and Web of Science, was conducted to identify randomized controlled trials (RCTs) published between 2014 and 2024 that investigated the effectiveness of non-pharmacological interventions for dysmenorrhea. The primary outcome was pain intensity reduction, while secondary outcomes included quality of life, absenteeism, and medication use. Data were pooled using a random-effects model, and standardized mean differences (SMDs) were calculated. Six RCTs met the inclusion criteria, encompassing a total of 600 participants. The non-pharmacological interventions evaluated included aerobic exercise, yoga, acupuncture, transcutaneous electrical nerve stimulation (TENS), heat therapy, and relaxation techniques. The pooled analysis revealed significant reductions in pain intensity across all interventions compared to control groups (SMD = -2.00, 95% CI: -2.39 to -1.61, p < 0.001). Aerobic exercise and yoga demonstrated the largest effect sizes (SMD = -2.5 and -2.5, respectively). Significant improvements were also observed in quality of life, absenteeism, and medication use. Non-pharmacological approaches, particularly aerobic exercise and yoga, are effective in managing dysmenorrhea symptoms. These findings strongly support the integration of non-pharmacological interventions into clinical practice as a first-line or adjunctive treatment option for dysmenorrhea.

Study of dielectric relaxation and electrical conduction mechanism in the double perovskite La2MnRuO6

We have prepared the La2MnRuO6 sample via the sol–gel self-combustion technique and studied the electrical modulus as well as the other dielectric properties using impedance spectroscopy. The Rietveld refinement of the powder XRD profile at ambient temperature revealed that only one phase is constituted in the elaborated sample. It crystallizes in the orthorhombic structure with Pbnm space group symmetry. The complex impedance spectroscopy was used to study the mechanism of electrical transport and dielectric relaxation. Jonscher’s universal power law controls accurately how the alternating current conductivity (AC) spectra behave. While the dielectric constant showed the effects of Maxwell-Wagner interfacial polarisation, the dielectric loss factor exhibited a frequency dependency at all the investigated values of the temperature. Two peaks can be seen in the imaginary component of the impedance Z″ spectra. The first peak is located in the low-frequencies region whereas the second peak is in the high-frequency range. A peak shift into the high-frequency region is observed when the temperature increases, which comes from the gathering at the interface of free charges with increasing temperature. Moreover, the activation energy values obtained from the conductivity were in good agreement with those obtained by the modulus.

Optimized energy storage performances via high-entropy design in KNN-based relaxor ferroelectric ceramics

Dielectric capacitors play an irreplaceable role in complex and integrated electronic systems. However, attaining ultrahigh recoverable energy storage density (Wrec) alongside energy storage efficiency (η) poses a formidable challenge, impeding the advance towards the miniaturization and integration of cutting-edge energy storage devices. In this work, a high-entropy strategy with a viscous polymer process is adopted, bringing about ultrafine grains and polar nanoregions (PNRs) accompanied by enhanced electrical homogeneity and polarization relaxation characteristics. As a result, an ultrahigh Wrec ∼ 7.51 J/cm3 is achieved in a high-entropy KNN-based energy storage ceramic with a high η ∼ 88.4% at 750 kV/cm. Moreover, the ceramic capacitor exhibits a colossal power density reaching approximately 420 MW/cm3 and a discharge energy density of approximately 4.85 J/cm3 at 160 ℃. Impressively, it maintains low variation rates of less than 4% across a broad temperature range from 20 ℃ to 160 ℃. The new approach opens avenues for the design and development of superior dielectric materials used in next-generation high-power pulse devices.

Advanced sensor performance: Investigating complexities of electrical resistance relaxation behavior in piezoresistive materials

Advanced sensor performance: Investigating complexities of electrical resistance relaxation behavior in piezoresistive materials

Correlated barrier hopping transport and non-Debye type dielectric relaxation in Zn2V2O7 pyrovanadate

Herein, the Zn2V2O7 electro-ceramic pyrovanadate was synthesized via a conventional solid-state reaction technique and calcined at 700 °C. The single phase formation of Zn2V2O7 pyrovanadate crystallized in the monoclinic structure with C12/c1 space group was confirmed by X-ray diffraction (XRD). The XRD powder diffraction profile was analyzed by Rietveld refinement to investigate the structural details of the compound. The complex impedance analysis was carried out in the frequency domain of 83−2×106 Hz over a temperature range of 453–613 K to study the electrical charge conduction and dielectric relaxation mechanism in the material which revealed the presence of the distribution of relaxation times with thermal charge activation. Depressed semicircles in the Nyquist plots were modeled by an equivalent circuit with configuration (RGCG)(RGBQGB) which resolved the contributions of grains and grain boundaries towards the transport properties of the material. The electrical conductivity spectra followed Jonscher's power law behavior and the temperature variation of frequency exponent suggested correlated barrier hopping (CBH) as the governing transport mechanism in the Zn2V2O7 pyrovanadate system. The comparison between scaling behaviors of imaginary parts of impedance and modulus advocated the temperature-independent nature of relaxation time distribution. The imaginary electrical modulus spectra were reproduced by the Kohlrausch, Williams, and Watt formulism, and the fitted parameters confirmed the non-Debye type nature of the dielectric relaxation. Further, the Haveriliak-Negami function was employed to investigate the dielectric response of the material which was found to be consistent with impedance, conductivity, and modulus analyses. The frequency dispersion of the tangent loss verified that the hopping mechanism was thermally activated.

Broadband Dielectric Spectroscopy: Unraveling Na+diffusion and mixed conduction in Na₂O-modified zinc phosphate glasses for electrode material applications

The fundamental understanding of electric charge (ion + polarons/electrons) transport and relaxation mechanism is essential for applications in solid state ionics. In present work, to study Na+ transport, the electrical conductivity of zinc phosphate glasses modified with Na2O has been investigated in temperature range 313K and 473K and frequency range of 100 mHz to 1 MHz. The experimental data of Nyquist plots is fitted with appropriate equivalent circuits at different temperatures which reveals presence of mixed conduction (polaronic + ionic) and Na+ diffusion (at 50 mol% Na2O) in studied glass samples. The values of frequency exponent (s) obtained from the fitting of experimental data of the real part of electrical conductivity with Almond–West equation (WAE) have been used to determine the conduction mechanism. The electric transport in studied glasses occurred via correlated barrier hopping and non-overlapping small polaron tunnelling conduction models depending on the glass composition and temperature range of investigation. Electric Modulus studies further supports the assertion of composition and temperature dependent conduction mechanisms. The activation energies determined from conductivity, electric modulus, and impedance measurements are found to be consistent, indicating a good correlation in the study.

Synthesis and study of structural, electric, and dielectric behavior of La0.5Sm0.2Sr0.3Mn1-xFexO3 perovskite

In this study, the synthesized samples La0.5Sm0.2Sr0.3Mn1-xFexO3 (x = 0.05, 0.15 and 0.20) were thoroughly investigated for their crystalline structure, electrical conductivity, and dielectric properties, the samples were prepared using autocombustion method. According to the X-ray diffraction study, the samples crystallized in an orthorhombic symmetry with the Pnma space group. To measure the dielectric characteristics, impedance spectroscopy was conducted over the temperature range of 100–260 K and a frequency range of 100 Hz to 1 MHz. Measurements of AC conductivity are indeed utilized to investigate the transport properties of materials being studied. The results indicated that both temperature and frequency significantly influence the conduction process. Three theoretical hypotheses were proposed to explain the hopping conduction: overlapping large polaron tunneling (OLPT), the non-overlapping small polaron tunneling (NSPT) mechanism, and correlated barrier hopping (CBH). It is also shown that the conductivity diminishes with an increase in Fe content. La0.5Sm0.2Sr0.3Mn1-xFexO3 (x = 0.05, 0.15 and 0.20) can be used in electronic applications because of the high permittivity values confirmed by the dielectric measurements. With the aim of evaluating the distinct impacts of electrodes, grain boundaries, and grains on the complex impedance results, an appropriate alternative electrical circuit was utilized. Analysis of the sample's modulus indicated non-Debye characteristics and electrical relaxation phenomena. The materials exhibit good electrical properties, as well as strong chemical and thermal stability.

An efficient electrode for reversible oxygen reduction/evolution and ethylene electro-production on protonic ceramic electrochemical cells

Protonic ceramic electrochemical cells (PCECs) have demonstrated great promise for applications in the generation of electricity, and the synthesis of chemicals (for example, ethylene). However, enhancing the electrochemical reactions kinetics and stability of PCECs electrodes is one grand challenge. Here, we present a novel electrode material via a co-doping of cesium (Cs) and niobium (Nb) on PrBaCo2O6−δ with the composition of PrBa0.9Cs0.1Co1.9Nb0.1O6−δ (PBCCN), which naturally decomposes into dual phases of a double-perovskite PBCCN (DP-PBCCN, ∼92.3 wt%) and a single-perovskite Ba0.9Cs0.1Co0.95Nb0.05O3−δ (SP-BCCN, ∼7.7 wt%) under typical powder processing conditions. PBCCN exhibits a low area-specific resistance (ASR) value of 0.107 Ω cm2, an outstanding performance of 2.04 W cm−2 in fuel cell (FC) mode, a current density of −2.84 A cm−2 at 1.3 V in electrolysis cell (EC) mode, and promising reversible operational durability of 53 cycles in ∼212 h at +/− 0.5 A cm−2 and 650 °C. Cs doping generates more oxygen vacancies and accelerates the oxygen exchange kinetics, while Nb doping effectively enhances the stability, as illustrated by the analyses of X-ray photoelectron spectroscopy, and electrical conductivity relaxations. When applied as the positrode for electrochemical non-oxidative dehydrogenation of ethane (C2H6) to ethylene (C2H4) on PCECs, it displays an encouraging C2H6 conversion of 12.75% and a C2H4 selectivity of 98.4% at 1.2 V.

Reduced Surface Area for the Oxygen Reduction Reaction in Porous Electrode via Electrical Conductivity Relaxation.

Oxygen reduction reaction (ORR) performance of porous electrode is critical for solid oxide fuel cells (SOFCs). However, the effects of gas diffusion on the ORR in porous media need further investigation, although some issues, such as nonthermal surface oxygen exchange, have been attributed to gas diffusion. Herein, La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) with various porosity, pore radii and gas permeability were investigated via the electrical conductivity relaxation method and analysed using the distributed of characteristic time (DCT) model. The ORR is revealed with three characteristic times, which are gas diffusion, oxygen exchange via the surface corresponding to small pores, and oxygen exchange to large pores. Gas diffusion delays the oxygen surface exchange reaction, resulting in very low chemical oxygen surface exchange coefficient compared with that obtained with dense sample under the assumption that all the surfaces are active for the ORR. Reduced surface area is thus defined to quantitatively represent the gas diffusion effects. The reduced surface area increases with increasing gas permeability, demonstrating the importance of electrode engineering for fast gas transport. Moreover, reduced surface area is suggested for replacing the specific surface area to calculate the electrode polarization resistance using the ALS model.

Efficient and Stable In Situ Self‐Assembled Air Electrodes for Reversible Protonic Ceramic Electrochemical Cells

AbstractReversible protonic ceramic electrochemical cells (R‐PCECs) have garnered significant attention owing to their proficiency in efficiently converting and storing energy. The performance of R‐PCECs is largely limited by the activity and durability of oxygen reduction/evolution reactions in air electrodes. Herein, an Nb and Y doped cobalt‐based double perovskite of PrBaCo1.8Nb0.1Y0.1O5+δ (denoted as PBCNY) is reported. The perovskite is however in situ assembled into a deficient‐PrBa1−xCo1.8Nb0.1−xY0.1−xO5+δ parental phase and a Ba2YNbO6 secondary phase during operation, accordingly demonstrating a low area‐specific resistance of 0.24 Ω cm2 at 600 °C. The high activity is attributed to the enhancement in oxygen vacancy concentration, oxygen surface exchange, and bulk diffusion coefficient, confirmed by X‐ray photoelectron spectroscopy and electrical conductivity relaxation. At 700 °C, when the PBCNY cathode is applied as air electrodes for R‐PCECs, a peak power density of 1.99 W cm−2 and a current density of −5.20 A cm−2 (at 1.3 V) are achieved in fuel cell (FC) mode, and electrolysis (EL) mode with appropriate Faradaic efficiencies. Furthermore, R‐PCECs with PBCNY air electrodes display promising operational stability in FC mode (over 100 h), EL mode (over 200 h), and reversible cyclic testing (29 cycles for 120 h).

Electrical conductivity and relaxation mechanisms of nanocrystalline Ba0.75Ca0.2Cs0.05TiO3

Ca and Cs doped barium titanate lead-free ceramic with the formula Ba0.75Ca0.2Cs0.05TiO3 has been prepared by the solid-state reaction method. X-ray diffraction (XRD) confirms the crystallization of the sample in a tetragonal structure with a P4mm space group. The phase purity and grain morphology were evaluated using X-ray diffraction and scanning electron microscopy (SEM). The material exhibits a primary phase of Ba0.75Ca0.2Cs0.05TiO3 with a minor secondary phase of BaO2, and the average grain size is determined to be 1.66 μm. Using non-destructive complex impedance spectroscopy (CIS), we extensively studied the electrical behavior, including complex impedance (Z*), complex modulus (M*), electrical conductivity, and relaxation mechanisms, of Ba0.75Ca0.2Cs0.05TiO3 over a wide temperature (85 K–290 K) and frequency range. The ac conductivity analysis reveals that the dominant conduction mechanism is the non-overlapping small polaron tunneling (NSPT) model. The impedance analysis indicates a single semi-circle in the real and imaginary parts, suggesting a single relaxation mechanism. Additionally, the activation energy was calculated to be approximately 0.0489 eV. These findings contribute to the understanding of the structural and electrical properties of Ba0.75Ca0.2Cs0.05TiO3, highlighting its potential applications in electronic devices such as capacitors, thermistors, and ferroelectric random access memories (FRAMs).

Electrical transport and dielectric relaxation mechanism in Zn0.5Cd0.5Fe2O4 spinel ferrite: A temperature- and frequency-dependent complex impedance study

In the present study, the frequency-dependent dielectric relaxation and electrical conduction mechanisms in sol-gel-derived Zn0.5Cd0.5Fe2O4 (ZCFO) spinel ferrite were studied in the temperature range of 343–438 K. The formation of the ZCFO spinel ferrite phase with space group Fd3m was confirmed by X-ray diffraction analysis. The dielectric relaxation and electrical conduction mechanisms were studied using complex impedance spectroscopy (CIS). In the Nyquist plots, depressed semicircles were fitted with an equivalent circuit model with configuration (RGBQGB) (RGQG), signifying the contributions from grain boundaries and grains to the charge transport mechanism in the sample. The frequency-dependent AC conductivity was found to follow Jonscher's power law, and the frequency exponent term depicted the overlapping large polaron hopping (OLPH) model as the dominant transport mechanism. The activation energies for conductivity, electric modulus and impedance were calculated to identify the nature of the charge carriers governing the relaxation and conduction mechanisms in the prepared sample. Complex modulus studies confirmed the non-Debye type of dielectric relaxation, whereas tangent loss and dielectric constant analyses confirmed the thermally activated hopping mechanism of charge carriers in Zn0.5Cd0.5Fe2O4 spinel ferrite.

Enhancing the CO2 Adsorption of the Cobalt-Free Layered Perovskite Cathode for Solid-Oxide Electrolysis Cells Gains Excellent Stability under High Voltages via Oxygen-Defect Adjustment.

Solid-oxide electrolysis cells are a clean energy conversion device with the ability to directly electrolyze the conversion of CO2 to CO efficiently. However, their practical applications are limited due to insufficient CO2 adsorption performance of the cathode materials. To overcome this issue, the A-site cation deficiency strategy has been applied in a layered perovskite PrBaFe1.6Ni0.4O6-δ (PBFN) cathode for direct CO2 electrolysis. The introduction of 5% deficiency at the Pr/Ba site leads to a significant increase in the concentration of oxygen vacancies (nonstoichiometric number δ of oxygen vacancies increased from 0.093 to 0.132), which greatly accelerates the CO2 adsorption performance as well as the O2- transport capacity toward the CO2 reduction reaction (CO2RR). CO2 temperature-programmed desorption indicates that A-site cation-deficient (PrBa)0.95Fe1.6Ni0.4O6-δ (PB95FN) shows a larger desorption peak area and a higher desorption temperature. PB95FN also exhibits a greater presence of carbonate in Fourier transform infrared (FT-IR) spectroscopy. The electrical conductivity relaxation test shows that the introduction of the 5% A-site deficiency effectively improves the surface oxygen exchange and diffusion kinetics of PB95FN. The current density of the electrolysis cell with the (PrBa)0.95Fe1.6Ni0.4O6-δ (PB95FN) cathode reaches 0.876 A·cm-2 under 1.5 V at 800 °C, which is 41% higher than that of PB100FN. Moreover, the PB95FN cathode demonstrates excellent long-term stability over 100 h and better short-term stability than PB100FN under high voltages, which can be ascribed to the enhanced CO2 adsorption performance. The PB95FN cathode maintains a porous structure and tightly binds to the electrolyte after stability testing. This study highlights the potential of regulating oxygen defects in layered perovskite PrBaFe1.6Ni0.4O6-δ cathode materials via incorporation of cation deficiency toward high-temperature CO2 electrolysis.

Effect of striae on the high temperature dielectric and electrical properties of lithium aluminosilicate glass-ceramics

Lithium Aluminosilicate glass-ceramics with striae (LAS-WS) and without striae (LAS-WoS) were processed using melt casting technique. LAS-WS and LAS-WoS samples were characterized and found stress birefringence >10 nm/cm and <10 nm/cm, respectively. LAS-WS and LAS-WoS samples were subjected to structural, microstructural, high temperature dielectric and electrical characterization. The presence of striation did not significantly affected the formation of β-spondumene structure during crystallization heat treatment. TEM image confirms the formation of nanocrystals in the glass matrix of lithium aluminosilicate glass-ceramics. The homogeneous distribution of LAS nanocrystals of average size of 3–6 nm is evident from TEM results. Stress birefringence distribution in lithium aluminosilicate glass-ceramic clearly shows the striae formation. Shadowgraphy images confirmed the striae free and striae containing regions in the glass-ceramic. The effect of striae on dielectric properties and AC conductivity was analysed using impedance spectroscopy and it was found that the value of the relative permittivity decreased from 415 (1.2 Hz) to 9.76 (1.2 MHz) for LAS-WoS and from 401 (1.2 Hz) to 10.3 (1.2 MHz) for LAS-WS, respectively. It was found that striae in LAS glass-ceramics influence the electrical impedance and AC conductivity relaxation process rather than relative permittivity. The effect of striae on crystallization and morphology are presented. Both the samples have shown crystallinity of more than 75 %. The electrical conductivity of σ = 2.0 × 10−3 S/cm for LAS-WoS and 2.7 × 10−3 S/cm for LAS-WS at 300 °C as well as σ = 4.6 × 10−3 S/cm for LAS-WoS and 6.9 × 10−3 S/cm for LAS-WS at 700 °C are found to be in good agreement due to increase in the electrical conductivity with temperature. The ionic conductivity of the material due to Li-ion mobility with respect to temperature and electric field and possible mechanism of AC conductivity are discussed. The results presented indicates the potential application of this material that demands high temperature operation of lithium aluminosilicate glass-ceramics.

Enhanced electrocatalytic activity of SrFe0.9Nb0.1O3-δ through in-situ synthesis of Sr3Fe1.8Nb0.2O7-δ coating

The influence of the heterogeneous interface is critical for the catalytic activity of the oxygen reduction reaction (ORR). This study demonstrates an enhancement of the electrocatalytic activity of the SrFe0.9Nb0.1O3-δ (SFN113) electrode through the construction of a SrFe0.9Nb0.1O3-δ-Sr3Fe1.8Nb0.2O7-δ (SFN113-SFN327) heterogeneous interface. By coating varying amounts of Sr(NO3)2 (0.1 g, 0.2 g and 0.3 g) on SFN113 (1 g), SFN113/327 composite electrodes with different amounts of triple conducting oxide SFN327 are in-situ synthesized by high temperature calcination. Electrical Conductivity Relaxation (ECR) tests show that SFN327 has superior oxygen surface exchange performance compared to SFN113, especially at lower temperatures. At 550 °C, the oxygen surface exchange parameter of SFN327 is 4.23 times higher than that of SFN113. Symmetric cell tests with SFN113/327||BaCe0.7Zr0.1Y0.1Yb0.1O3-δ (BCZYYb)||SFN113/327 configuration and single cell tests with Ni-BCZYYb||BCZYYb||SFN113/327 configuration indicate that the SFN113/327 composite electrode with a mass ratio of 1:0.2 displays the best electrocatalytic performance, achieving a power output of 502 mW cm−2 at 700 °C. The work not only in-situ synthesizes the SFN113/327 triple conducting composite electrode, but also introduces a novel method for developing proton conducting electrode materials.

Effect of hetero-valence ions on structural and electrical properties of La2Ni(Mn0.5Ti0.5)O6 ceramics

The study of powder X-ray diffraction of La2Ni(Mn0.5Ti0.5)O6 (0.5LNMT) confirms a multi-phasic composition. The monoclinic P21/n phase content dominates. Occurrence of minor rhombohedral R3‾c phase and precipitates of MnO2 and La2MnO4 were detected. The morphology was analyzed using a SEM test and ceramics showed a porous structure and variation in the grain size below 4 μm. Dielectric permittivity of marked magnitude varies from ∼30 to ∼100 000 when temperature increases. Dielectric loss coefficient frequency dependence exhibits well-defined dielectric relaxation peaks, which were found to obey the Arrhenius law with the activation energy of 0.29 eV, below the presumed phase transition. Two sets of relaxation peaks in the imaginary part of electric modulus spectra relate to relaxations of different activation energies of 0.28 eV and 0.38 eV. An optical gap magnitude of 0.8 eV was determined from the diffuse reflectance spectrum in the Vis-NIR range. It compares with the band gap estimated from the X-ray photoelectron spectroscopy test. We also compare the influence of doping ions on the crystal lattice of the surface and the bulk ceramics. Electrical conductivity relaxation processes were attributed to the electron hopping mechanism between multi-valence Mnk+ and Nin+ ions’ states, which were determined from XPS analysis. The dc resistivity shows thermally generated dependence. Activation energy Edc magnitude varies between 0.27 and 0.37 eV which indicates the occurrence of defects and structural disorder. Such disorder correlates to the variable range hopping of small polarons involved in electrical conductivity. The density of states near Fermi energy was estimated N(EF) = 2.1 × 1025 eV−1 m−3. The 0.5LNMT application prospects were discussed.

Link between Yoga and Heart Rate Variability: Can Yoga Enhance the Cardiac Resonance.

Cardiac resonance is a complicated phenomenon involving the coordinated oscillations of numerous circulatory system components, such as electrical activity, contraction and relaxation, and blood flow. It is critical for the normal functioning of the heart and for maintaining blood flow throughout the body. Cardiac resonance is defined as a series of tiny waves produced by the heartbeat and overlaid on flow data and airway pressures. A variety of technologies, including cardiac magnetic resonance (CMR) imaging, can be used to identify these waves. CMR is a strong noninvasive method for seeing and quantifying heart anatomy and function in great detail. CMR can be used to assess cardiac resonance in both healthy and heart disease patients. A regular and coordinated pattern of oscillations characterizes cardiac resonance in healthy persons. In patients with heart illness, however, cardiac resonance can be interrupted, resulting in diminished cardiac function and decreased blood flow. The intricate role of cardiac resonance in cardiac health and disease is continuously being studied by researchers. However, it is obvious that cardiac resonance is an exciting area of research that has the potential to change the way to identify and treat heart illness. Yoga is a mind-body practice that has been demonstrated to have numerous cardiovascular health advantages, such as improved heart function, reduced inflammation, and lower blood pressure. Yoga is hypothesized to promote cardiac resonance by encouraging coordinated oscillations of numerous cardiovascular system components. Various researches have shown buoyant results such as yoga can be helpful in improving heart rate variability, cardiac resonance and reducing arterial stiffness. Stress can disrupt cardiac resonance and increase the risk of heart disease. More research is needed to completely understand the mechanisms that impact cardiac resonance and the long-term advantages of yoga for heart health.

Machine learning-assisted equivalent circuit identification for dielectric spectroscopy of polymers

Polymers have become indispensable across fields of application, and understanding their structure–property relationships and dynamic behaviour is essential for performance optimization. Polymer membranes, particularly ion exchange membranes, play a crucial role in renewable energy conversion technologies, fuel cells, solar energy conversion, and energy storage. In this context, broadband dielectric spectroscopy (BDS) offers a powerful, non-destructive approach to investigate the electrical response and relaxation dynamics of polymers. These properties are investigated by parametrizing the system’s impedance response in terms of a network of circuit elements, i.e. the electrical equivalent circuit (EEC), whose impedance resembles the one of the system under investigation. However, the determination of the EEC from BDS data is challenging due to system complexity, interdependencies of circuit elements, and researcher biases. In this work, we propose a novel approach that incorporates a convolutional neural network (CNN) model to predict the EEC topology. By reducing user bias and enhancing data analysis, this approach aims to make BDS accessible to both experienced users and those with limited expertise. We show that the combination of machine learning and BDS provides valuable insights into the dynamic behaviour of polymer membranes, thus facilitating the design and characterization of tailored polymers for various applications. We also show that our model outperforms state-of-the-art machine learning methods with a top-5 accuracy of around 80% for predicting the circuit topology and a parameter fitting error as low as 0.05%.