Conductive Loss Research Articles

An analytical model for predicting the magnetization loss in HTS sector-shaped conductors for fusion

Abstract Within the framework of magnetic confinement fusion, several projects worldwide are demonstrating the possibility of integrating high-temperature superconductors (HTS) in the coil systems. HTS-based technologies are highly attractive for practical applications because they can extend the operating margins of fusion coils in terms of higher temperatures, transport currents and magnetic fields. Based on the results achieved with the twisted-stacked tape cable, we have designed a novel low-loss HTS sector cable-in-conduit conductor, with a target of 60 kA at 4.5 k, 18 T, which is presently of interest for the DEMO Central Solenoid coil. In HTS cables, the AC losses can represent a significant limiting factor, therefore they must be taken into consideration both in the design phase and in the assessment of the overall magnet thermal budget. In this work, to assess the loss behavior and to optimize the cable design, we have explored different aspect ratios and arrangements of the stacked tapes within the cable layout. The magnetization losses are calculated with a 2D finite-element model based on the T-A formulation and analytical approximations based on the Brandt-Halse critical state model. Specifically, we have developed an analytical formulation that allows for the calculation of the instantaneous power losses in HTS stacked cables with a limited number of tapes per stack, achieving sufficient accuracy at high fields. The analytical model enables a sufficiently accurate assessment of the heat deposited on the conductor during those particular instants of a plasma scenario where the variation of the field is very high, such as during the critical initial discharge period of the plasma initiation.

Analysis of Adherence to AAO-HNSF Clinical Practice Guidelines for Sudden Hearing Loss.

To assess adherence to the 2019 American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNSF) guidelines for the diagnosis and management of sudden hearing loss (SHL) and sudden sensorineural hearing loss (SSNHL). Retrospective cohort. TriNetX, a de-identified healthcare database. Evaluation focused on the percentage of patients undergoing proper guideline-adherent workup and treatment for SHL. Key measures include audiogram testing within 2 weeks for distinguishing SSNHL from CHL. For SSNHL patients, MRI or auditory brainstem response (ABR) testing should be obtained, and steroids and/or hyperbaric oxygen may be offered within 2 weeks. There were 24,203 SHL patients, 59.1% (n = 14,309) of whom underwent recommended audiogram testing, with 35.8% (n = 8,674) completing it within 2 weeks. Overall, 3,107 were diagnosed with unilateral SSNHL, 104 with unilateral conductive hearing loss (CHL), 121 with mixed hearing loss, and 10,977 were lost to follow-up. Among 3,107 SSNHL cases, just 25.5% (n = 791) obtained MRI/ABR within 1 month, and vestibular schwannoma was diagnosed in 3.5% (n = 28). Additionally, steroids were prescribed to 54.5% (n = 1,692), and <0.3% (n ≤ 10) received hyperbaric oxygen. In accordance with strong recommendations against or insufficient evidence to support the following diagnostics and treatments, 2.0% (n = 63) underwent a CT scan, less than 0.3% (n ≤ 10) were prescribed vasodilators or thrombolytics, and 3.5% (n = 108) were on antivirals. There is a significant opportunity for improvement in evaluating patients with SHL, specifically SSNHL. Proper adherence to guidelines may improve screening, detection, and management of neurotologic pathologies, including vestibular schwannoma.

Ultralight SiO2 Nanofiber-Reinforced Graphene Aerogels for Multifunctional Electromagnetic Wave Absorber.

The high-efficiency utilization of two-dimensional (2D) graphene layers for developing durable multifunctional electromagnetic wave (EMW) absorbing aerogels is highly demanded yet remains challenging. Here, renewable, low-density, high-strength, and large-aspect-ratio ceramic silicon dioxide (SiO2) nanofibers were efficiently prepared to assist in the preparation of ultralight yet robust, highly elastic, and hydrophobic graphene aerogels using facile, scalable freeze-drying followed by a carbonization approach. The ceramic nanofibers efficiently prevent the agglomeration of graphene and enhance interfacial interactions, significantly promoting mechanical strength. In addition to the high conduction loss capability derived from the interconnected graphene network, high interfacial polarization derived by abundant heterogeneous interfaces is accomplished for the three-dimensional (3D) hybrid aerogels. The hybrid aerogels thus showcase excellent EMW absorption performance, involving a minimum reflection loss of -74.5 dB at 1.8 mm and an effective absorption bandwidth of 5.7 GHz, comparable to those of the best EMW absorbers. Furthermore, the integration of one-dimensional SiO2 and 2D graphene into 3D hybrid aerogels enables remarkable photothermal antibacterial, photothermal oil absorption, and thermal insulation performances. This work thus provides a type of ultralight ceramic/graphene aerogel with a high-efficiency utilization of graphene for accomplishing high-performance multifunctional applications.

Middle Ear Malformations

Middle ear malformations (MEMs) represent a diverse group of congenital anomalies with significant implications for auditory function. These malformations, which occur in approximately 0.5 to 3% of conductive hearing loss cases, can arise from various genetic and environmental factors. They often manifest unilaterally and may occur in isolation or as part of a syndromic condition. MEMs are closely associated with abnormalities of the external ear and less frequently with inner ear anomalies.Embryologically, the middle ear develops from the first and second pharyngeal arches, with interactions between the ectoderm and endoderm contributing to the formation of essential structures such as the tympanic membrane, ossicles and Eustachian tube. Disruptions in these developmental processes can lead to a spectrum of MEMs, ranging from minor defects to severe malformations affecting multiple middle ear components.Clinical management of MEMs requires a multidisciplinary approach, involving otolaryngologists, pediatricians, and audiologists. Early intervention with appropriate hearing aids, including conventional hearing aids and bone conduction devices, is essential to mitigate the impact of conductive hearing loss on speech and language development, particularly in children.Surgical planning involves comprehensive preoperative assessment, including high-resolution computed tomography imaging to evaluate middle ear anatomy, the facial nerve course, and vascular anomalies. Traditional surgical approaches such as stapesplasty and tympanoplasty remain mainstays for correcting specific middle ear defects, while advances in technology have expanded the role of active middle ear implants in treating special cases.In conclusion, MEMs represent a heterogeneous group of congenital anomalies with diverse etiologies and clinical implications. A thorough understanding of their embryological basis, genetic underpinnings, and surgical management strategies is crucial for optimizing outcomes in affected individuals.

Fabrication and electromagnetic wave absorption modulation of high-performance (TaNbTiV)₂AlC MAX Phase

Electromagnetic (EM) wave technology is widely used in both military and civilian applications, increasing interest in EM wave absorption materials for information security and environmental protection. This study examines the synthesis and EM wave absorption properties of M-site compositional complex MAX phase (TaNbTiV)2AlC. Using Ta, Nb, Ti, V, Al, and graphite powders, pure (TaNbTiV)2AlC was synthesized at 1400°C. SEM and EDS confirmed homogeneous elemental distribution and morphology, while TEM and SAED analyses revealed the atomic structure. EM wave absorption was tested using (TaNbTiV)2AlC/paraffin wax composites with varying (TaNbTiV)2AlC content in the 2-18 GHz range. The main attenuation mechanisms identified were interfacial polarization, dielectric loss, and conductive loss. Optimal absorption was achieved at 30 vol% (TaNbTiV)2AlC, with a reflection loss of -43.83 dB and an effective absorption bandwidth of 3.49 GHz. The study demonstrates that the control of establishing a “near-conductive network” of fillers could be advantageous in achieving optimal electromagnetic wave absorption performance using fillers possessing high electrical conductivity, such as MAX phase materials.

In situ formation SiC nanowires on loofah sponge-derived porous carbon for efficient electromagnetic wave absorption

A lightweight, heterogeneous, three-dimensional network-structured composite has been meticulously developed with the specific goal of optimizing impedance matching and elevating electromagnetic wave absorption properties. SiC nanowires-carbon composites were synthesized through a novel process involving combined carbothermal reduction and chemical vapor deposition, utilizing loofah sponge as the foundational material. Accessible and cost-effective organosilane waste was applied as the silicon source. The resulting composites manifest exceptional electromagnetic wave absorption performance with a minimum reflection loss of − 46.34 dB and a wide effective bandwidth of 3.84 GHz at a thin thickness of 1.9 mm. Superior electromagnetic wave absorption is attributed to synergistic interplay of multiple interfacial polarizations, dipole polarization, conductive losses, and multiple reflections and scattering. This work presents an innovative pathway toward fabricating highly efficient electromagnetic wave-absorbing materials while effectively repurposing recycled waste.

Quantifying Heterogeneous Interface Effect of Fe3O4(111)/C for Enhanced Low-Frequency Electromagnetic Wave Absorption

How to tailor electromagnetic parameters of multi-component materials is the fundamental issues for low-frequency electromagnetic wave absorbers (EMA). However, there remains a challenge to accurately elucidate the impact of respective components at heterogeneous interfaces on the EMAs, not to mentioning the further quantitative contribution of the interfacial effect to the electromagnetic loss. In this paper, we for the first time separated the Fe3O4(111)/C heterogeneous interface of Fe3O4@C via a controllable interfacial separation strategy, meanwhile ensuring the consistent microstructure and the ratio of each component, as well as the unchanged macroscopic structure of the particles. Once all potential influences on electromagnetic parameters have been independently studied, the unique difference in heterogeneous interfaces enabled us to quantitatively evaluate the effect of them on electromagnetic parameters. Both experimental and density functional theory (DFT) calculation results consistently demonstrate that the Fe3O4(111)/C heterointerface increases carrier concentration and conductivity, thereby enhancing the imaginary part of the dielectric constant. Very distinguished from traditional interfacial polarisation mechanism presented in previous publications, this study introduces a novel interfacial loss mechanism primarily characterized by conductivity loss, which is rigorously investigated in a quantitative way. This discovery offers a novel approach for designing controllable heterogeneous interfaces and manipulating electromagnetic parameters in multicomponent EMAs.

Chain-arranged Ni1-xCox micro/nano particles prepared via a magnetic field-assisted reduction for enhanced electromagnetic wave absorption

Transition metal magnetic alloys have garnered extensive interests in electromagnetic wave absorption due to the remarkable magnetic loss capacity and unique magnetism-frequency characteristics. Herein, we report a novel magnetic absorbent of Ni1-xCox micro chains that synthesized through a magnetic field-assisted reduction method. The precipitated Ni1-xCox particles could be connected and aligned during the magnetic reduction process. Due to the modified electronic structure of the Co active site by Ni, the particle size in the Ni1-xCox micro chains noticeably increases with increased x. Meanwhile, the complex dielectric constants exhibit a decreasing trend, which contributes to the improved impedance matching and higher resonance frequencies. The connected Ni1-xCox micro/nano particles not only benefit to the conductive loss, but also strengthened the polarization loss on the contacted interfaces among the particles. As a result, significantly enhanced electromagnetic wave absorption performance was obtained with the minimum reflection loss of −21.0 dB and the effective absorption bandwidth of 3.92 GHz at a thickness of only 1.35 mm. Overall, this work has demonstrated the strategy of designing aligned bimetallic absorbent, possessing great potentials in improving their microwave absorption properties.

Enhanced high-temperature energy storage performance in all-organic dielectric films through synergistic crosslinking of chemical and physical interaction

Advanced electronic devices and energy systems urgently require high-temperature polymer dielectrics that can offer both high discharge energy density and energy storage efficiency. However, the capacitive properties of most polymers sharply deteriorate at elevated temperatures, due to the significant rise in leakage current density and energy loss. Herein, a new design approach is adopted to fabricate high-temperature polyetherimide (PEI) dielectrics with chemical and physical cooperative crosslinking networks, the dual-crosslinked PEI dielectrics are prepared through amine crosslinking agent and the electrostatic interaction of oppositely charged phenyl groups between triptycene (TE) and PEI chain segments. Benefiting from the increased crosslinking sites, the dual-crosslinked PEI films achieve the simultaneously enhancement in Tg, modulus and bandgap compared to un-crosslinked and single-crosslinked polymers. Meanwhile, the PEI with dual-crosslinked network displays higher chain packing density, effectively reducing the mean motion pathways of charge carriers and the conduction loss inside polymer dielectric. Consequently, the dual-crosslinked PEI containing 0.25 wt% TE delivers an outstanding discharge energy density of 2.69 J/cm3 and retains excellent cyclability after 100,000 charge–discharge cycles at 200 ℃. Additionally, finite element analysis and molecular dynamics simulation further confirm that less Joule heat and tighter chain structure are formed in the dual-crosslinked polymer dielectric. This research offers a novel methodology to prepare high-performance polymer dielectrics for high-temperature applications.

Thermodynamic and Kinetic Studies on the Pyrophoricity of Uranium Flakes

The objective of this work was to arrive at quantitative estimates of pyrophoricity of uranium in different geometries. The major source of heat generation was identified to be exothermic chemical reactions of uranium with moist air. Time evolution of temperature was studied for uranium considering 3D conduction and convection heat loss routes using Finite Element Analysis. Auto ignition temperature for uranium flakes was quantified using heat balance equation and was found to be around 500 K. Excess heat generation rates needed to cause auto ignition of uranium flakes at room temperature were also estimated. The major sources of excess heat leading to its ambient ignition could be attributed to friction and other exothermic chemical reactions of process impurities in uranium.

Pressure induced tunable physical properties of cubic KHgF3 fluoro-perovskite: A first principle study

The structural, electronic, optical, mechanical, and thermodynamic properties of KHgF3 perovskite under various hydrostatic pressures are examined in this study in the frameworkof Density Functional Theory (DFT) with the Generalized Gradient Approximation (GGA) Perdew-Burke-Ernzerhof (PBE) exchange–correlation function. Tunable physical properties have been observed in KHgF3 as pressure is incrementally applied. The investigated compound displays mechanical instability beyond the pressure range of 0 to –10 GPa, as confirmed by the elastic constant analysis. Under ambient pressure, the lattice constants of KHgF3 closely align with theoretically calculated values, affirming the accuracy of this investigation. In addition, the bandgap of KHgF3 narrows with increasing pressure, facilitating easier electron transition from the valence band to the conduction band. The study reveals that when subjected to different hydrostatic pressures, fluctuations are observed in the peaks of the conductivity spectrum, loss spectrum, and absorption spectrum, particularly shifting towards higher photon energies, as analyzed through the optical properties. Moreover, KHgF3 exhibits ductile behavior at 0 GPa pressure, and this ductility rises with pressure. Thermodynamic analysis reveals a decrease in Debye temperature with increasing pressure, while the melting temperature rises correspondingly. The findings of this investigation also imply that KHgF3 can be a good candidate for optoelectronic device application under different hydrostatic pressures.

Honeycomb-like Microthermal Traps on a Photothermal Surface for Highly Efficient Solar Evaporation.

Solar evaporation is an ecofriendly and practical method for seawater desalination. The photothermal layer, which absorbs solar energy and converts it to thermal energy, plays a crucial role in enhancing the efficiency of the evaporator. However, structural design methods for photothermal layers are often complex and energy-intensive. This work reports a simple and efficient strategy for fabricating a necklace-like beaded nanofiber self-organized honeycomb-structured photothermal material. The honeycomb-like cavities form numerous microscale thermal traps, achieving thermal localization while maintaining high energy utilization efficiency, which not only increases light absorption but also facilitates the diffusion and escape of steam. Besides, the hydrophobic honeycomb layer separates the photothermal layer and the interface water, which reduces considerable heat conduction loss and achieves an effective antisalting performance. These functional features endow the evaporator with an evaporation efficiency of 92.9%, and the evaporation rate reaches 2.11 kg m-2 h-1 at 1 sun irradiance, demonstrating its great potential for practical solar-driven seawater desalination under natural sunlight.

Model of superior semicircular canal dehiscence: asymmetrical vestibular dysfunction induces reversible balance impairment

BackgroundSuperior semicircular canal dehiscence (SSCD) is a vestibular-cochlear disorder in humans in which a pathological third mobile window of the otic capsule creates changes to the flow of sound pressure energy through the perilymph/endolymph. The primary symptoms include sound-induced dizziness/vertigo, inner ear conductive hearing loss, autophony, headaches, and visual problems. We have developed an animal model of this human condition in the Mongolian Gerbil that uses surgically created SSCD to induce the condition. A feature that is unique in this model is that spontaneous resurfacing of the dehiscence occurs via osteoneogenesis without a subsequent intervention. In this study, we completed our assessment of this model to include reversible asymmetrical vestibular impairments that interfere with balance.MethodsAdult Mongolian gerbils (N = 6) were trained to complete a balance beam task. They were also trained to perform a Rotarod task. After 10 days of training, preoperative ABR and c+VEMP testing was followed by a surgical fenestration of the left superior semicircular canal. Balance beam testing recommenced at postoperative day 6 and continued through postoperative day 15 at which point final ABR and c+VEMP testing was carried out.ResultsBehavioral comparison of preoperative and postoperative performance show a significant decrease in Rotarod performance, increased rates of falling, and an increase in time to cross the balance beam. Impairments were the most significant at postoperative day 7 with a return toward preoperative performance by postoperative day 14. This behavioral impairment was correlated with residual impairments to auditory thresholds and vestibular myogenic amplitudes at postoperative day 14.ConclusionThese results confirm that aberrant asymmetric vestibular output in our model of SSCD results in reversible balance impairments. The level of these behavioral impairments is directly correlated with severity of the vestibular dysfunction as we have previously reported for peripheral ear physiology and cognition.

The synergistic effects on the magnetic CoNi and Fe3O4 nanoparticles co-embedded porous carbon toward enhanced microwave absorbing performance

Abstract Lightweight and environmentally friendly three-dimensional biomass-derived porous carbon (3D BPC) holds great potential as a highly effective material for microwave absorption (MA) applications. However, the high complex permittivity and lack of magnetic loss in a single 3D BPC lead to impedance mismatching and a limited absorption bandwidth. Developing 3D BPC–based absorbers with multiple loss mechanisms and excellent impedance matching remains a notable yet challenging task. In this study, inspired by a synergistic composition and microstructure design, 3D BPC co-embedded with magnetic cobalt–nickel (CoNi) and iron(III) oxide (Fe3O4) nanoparticles (3D BPC@CoNi@Fe3O4) was developed. 3D BPC@CoNi@Fe3O4 exhibited consistently low complex permittivity, primarily due to the suppression of conductive loss, whereas the introduction of magnetic phases (CoNi and Fe3O4) enhanced the magnetic loss. Optimised impedance matching, achieved through the synergistic regulation of the electromagnetic parameters, emerged as the key mechanism for improving the MA properties. The as-synthesised 3D BPC@CoNi@Fe3O4 composite, with only 20 wt.% loading demonstrated a wide effective absorption bandwidth (reflection loss [RL] &lt; −10 dB) of 6.08 GHz and an impressive minimum RL value of −40.08 dB. These findings offer valuable insights into the development of high-performance 3D BPC–based microwave absorbers through composition and microstructure optimisation.

Minor's Syndrome or Dehiscence of the Superior Semicircular Canal: A Case Report

Semicircular canal dehiscence is a congenital syndrome that mainly affects the superior and, less commonly, the posterior semicircular canal in the temporal bone. This syndrome was first reported by Minor et al. in 1998. The prevalence is about 0.5% in the general population. The most characteristic symptom is the Tullio phenomenon, predominantly vertigo and nystagmus. Hearing loss (in particular conductive loss) often completes overall clinical picture. The dehiscence may be completely asymptomatic, in which case it is seen as an incidental finding on radiological investigations. Audiological evaluation includes audiometry and vestibular evoked myogenic potentials (VEMPs). Clinical symptoms are based on the pathophysiological concept of a third mobile window within the inner ear. Diagnosis is confirmed by high resolution petrous temporal bone CT with multiplanar reconstructions (MPRs) in the plane of the canal (Pöschls’ plane for the superior semicircular canal) and 3-D surface reconstructions. MR findings are less sensitive for this entity. The most common differential diagnosis is otosclerosis. Clinical–radiological correlations have therapeutic applications even though the indication for surgery depends on the severity of the vestibular symptoms.

Audiological and Subjective Benefits in a Child with Microtia and Atresia After Sequential Bilateral Implantation with Active Bone Conduction Devices: A Case Study

Background: With bilateral hearing loss, the main problems for the patient are speech understanding in noise and, especially in asymmetrical hearing loss, an inability to correctly localize sound sources. There are multiple methods of treatment and rehabilitation for people with conductive hearing loss, and one of them is to use an active bone conduction implant. This case study is designed to evaluate the auditory benefits and sound localization accuracy with active bilateral bone conduction implants—in comparison to unilateral ones—in a patient with congenital bilateral conductive hearing loss caused by a congenital malformation. We assess subjective and audiological benefits (functional, directional hearing, speech comprehension in quiet and noise). Case report: This study describes the results in a 15-year-old patient with bilateral congenital malformation of the outer ears and associated conductive hearing loss who was treated with two Bonebridge active bone conduction implants. Speech recognition ability, hearing thresholds, and sound localization were tested under three conditions: unaided, unilateral on the right-side, and bilateral on both sides. The patient filled in an Abbreviated Profile of Hearing Aid Benefit questionnaire (APHAB) to evaluate limitations in daily life caused by hearing impairment. The results show an improvement in free-field hearing thresholds and the ability to discriminate speech, both in quiet and in noise after implantation. Subjectively, the patient had significantly fewer problems with two implants than with one (or with no implant) in terms of hearing in everyday situations. Conclusions: Unilateral use of the Bonebridge device in a patient with congenital bilateral conductive hearing loss did not provide full benefits. However, bilateral implantation improved speech understanding in noise and sound localization.

Molecular and Clinical Heterogeneity in Hungarian Patients with Treacher Collins Syndrome—Identification of Two Novel Mutations by Next-Generation Sequencing

Treacher Collins syndrome (TCS) is a rare congenital craniofacial disorder with variable penetrance and high genetic and phenotypic heterogeneity. It is caused by pathogenic variants in the TCOF1, POLR1D, POLR1C, and POLR1B genes, and its major characteristic features are malar and mandibular hypoplasia, downward slanting of the palpebral fissures, and conductive hearing loss. In this study, five patients (two males and three females, age range from 2 to 29 years) with TCS were tested by Next-Generation Sequencing (NGS)-based sequencing and clinically characterized. Genetic analyses detected two deletions and one insertion in the TCOF1 gene and one missense variant in the POLR1D gene. Two novel mutations, c.1371_1372insT (p.Lys458*) in the TCOF1 gene and c.295 G&gt;C (p.Gly99Arg) in the POLR1D gene, were identified. Moreover, two already known mutations, c.4369_4373del (p.Lys1457Glufs*12) and c.2103_2106del (p.Ser701Argfs*9) in the TCOF1 gene, were detected. The novel TCOF1 c.1371_1372insT mutation was associated with mild craniofacial manifestations and very rare symptoms of TCS, i.e., developmental delay and moderate intellectual disability. Although incomplete penetrance is a known phenomenon in TCS, surprisingly, the majority of our patients inherited the disease-causing variants from an asymptomatic mother. The unique feature of our study is the observation of causative mutation transmission between asymptomatic family members. Our results expanded the clinical and mutational spectrum of TCS and further confirmed the inter- and intra-familial variability of this disorder.

Ultralight Cellulose-Derived Carbon Nanofibers from Freeze-Drying Emulsion Towards Superior Microwave Absorption

Carbon nanofibers (CNFs) are usually prepared by the carbonization of cellulose aerogels obtained from freeze-drying. However, cellulose with low concentration (below 1 wt%) is required to maintain the good porosity of the aerogels due to the strong hydrogen bonding between the cellulose molecules. In order to address this problem, here, ultralight cellulose-derived CNFs have been fabricated by freeze-drying cyclohexane (CHE)/cellulose nanofiber emulsions and carbonization. Field emission scanning electron microscopy, Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy are used to characterize the resulting CNFs. It is found that the CNFs consist of three-dimensional carbon networks, whose microstructure is easily adjusted by changing the CHE ratio (from 0 to 25 vol%) in the emulsions. The CNFs with high porosity are attributed to the fact that CHE as the oil phase can effectively weaken the hydrogen bonding and reduce the aggregation of the cellulose nanofibers. Carbon lattice defects and residual oxygen-containing functional groups are regarded as polarization centers, leading to the enhancement of dielectric loss. The conductive carbon networks also improve the conductive loss. All these factors improve the microwave absorption performance of the CNFs. So, the produced CNFs exhibit a superior electromagnetic wave performance with a minimum reflection loss of −42.18 dB and effective absorption bandwidth up to 4.9 GHz at 2 mm with a filling ratio of 2 wt%. This work provides a simple, low-cost, and sustainable synthesis route for CNFs used for ultralight high-performance microwave absorption materials.

Modelling of Power Semiconductor Devices Switching and Conduction Losses in a Power Electronic System

In power converters, power semiconductor devices, mainly Insulated-Gate Bipolar Transistor (IGBT), are generally used as they are less costly and capable of converting electrical energy into high frequency and voltage. It is critical to accurately determine the switching and conduction losses of power devices before they are assembled into an electronic system. The accurate values help to minimize power loss in a power converter system. With the aid of simulation, design problems are identified to help eliminate device destruction, and critical parameters are monitored. In addition, costly equipment for measuring purposes and testing prototypes is not required at the initial design stage. This research uses simulation work in a power converter system to predict IGBT and diode losses with varied frequencies and voltages. The predictive modelling is produced using regression analysis. The models have been validated by R square (R2) and Mean Absolute Percentage Error (MAPE) techniques. This work is aimed at providing a supervised learning technique mainly used in a machine learning environment, in line with the technological development in the semiconductor industry. With the simulation performed in this work, the efficiency of a boost converter system is enhanced as it shows the models have a good fit with an R2 value of almost 1, and MAPE values are noticed to be less than 5%.

Solid-State Lithium Batteries with In Situ Polymerized Acrylate-Based Electrolytes Capable of Electrochemically Stable Operation at 100 °C.

Solid polymer electrolytes (SPEs) typically consist of salts with mobile anions that could cause instabilities and parasitic side reactions in solid-state lithium (Li) batteries. To address this challenge, single-Li-ion conducting (SLIC) SPEs, where anions of Li salts are covalently attached to the polymer backbone, have been utilized to reduce the number of mobile anions. This approach improves the cationic transference number but is accompanied by a loss of ionic conductivity. In this work, we investigate a synergetic approach of using both a polymerizable SLIC salt and a conventional Li salt in a polymer matrix by in situ polymerization of the poly(propylene glycol) acrylate (PPGA) monomer. The synthesized hybrid SPEs show a high ionic conductivity of up to ∼2 × 10-4 S cm-1 and a relatively high Li-ion transference number of ∼0.4. With a significantly reduced fraction of mobile anions in the combined salt SPE, in situ polymerized SPE cells with a LiFePO4 (LFP) cathode achieve a stable performance for over 100 cycles at temperatures as high as 100 °C, which is unattainable with conventional Li salts or electrolytes. Furthermore, solid-state nuclear magnetic resonance spectra provide additional insights into differences in Li nucleus environments and emphasize a reduction in activation energy for hybrid SPEs due to their more open structure. This study opens the path for the fabrication of high-performance solid polymer Li batteries capable of operating at high temperatures using commercial battery fabrication equipment, as in situ polymerized acrylate-based polymers provide drop-in compatibility with conventional battery production, ease of acrylate polymerization, and inexpensive, facile SPE chemistry. We expect that further tuning of the acrylate-based SPE composition may allow further increases in its conductivity without sacrificing its electrochemical stability or mechanical properties.