Brazilian Journal of Physics最新文献_第4页

High-Performance PVA/Graphene Oxide Composite for Cost-Effective and Sustainable Piezoelectric Energy Harvesting 用于低成本、可持续压电能量收集的高性能 PVA/氧化石墨烯复合材料

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-03-05 DOI: 10.1007/s13538-025-01728-7

M. P. Trasadiya, A. M. Vora

{"title":"High-Performance PVA/Graphene Oxide Composite for Cost-Effective and Sustainable Piezoelectric Energy Harvesting","authors":"M. P. Trasadiya, A. M. Vora","doi":"10.1007/s13538-025-01728-7","DOIUrl":"10.1007/s13538-025-01728-7","url":null,"abstract":"<div><p>This study explores the piezoelectric generator prototype, utilizing the PVA and graphene oxide composite for the first time, demonstrating superior energy conversion efficiency and power output under various mechanical stimuli, such as vibrations and pressure fluctuations. Graphene oxide and nanosheets were extracted by intercalating a 1 M HNO<sub>3</sub> solvent into the graphitic layers. This process involved applying a voltage bias of 2 V DC for 5 min, followed by increasing the voltage to 6 V DC for 5 h. Graphene oxide is identified via X-ray diffraction (XRD), ultraviolet–visible spectroscopy (UV–VIS), and Fourier transform infrared spectroscopy (FTIR). PVA typically peaks at around 2θ = 19.9°, which is the (101) plane. The direct energy bandgaps of the produced composite PVA/GO at 1 wt.% and 2 wt.% are 3.681 eV and 3.231 eV, respectively. FTIR spectra analysis of the PVA/graphene oxide composite reveals characteristic peaks from both components, indicating successful incorporation. The fabricated device, featuring a sandwich structure, exhibits superior performance with an impressive output voltage of approximately 15 Vpp. This device could be very effective in energy-harvesting applications. EDAX analysis shows that the carbon-to-oxygen ratio of approximately 3.86:1 is typical of well-oxidized graphene oxide, indicating a high oxidation level.</p></div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143553822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Machine Learning–Assisted Design of Ytterbium-Based Materials with Tunable Bandgaps and Enhanced Stability

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-03-04 DOI: 10.1007/s13538-025-01732-x

Sajjad H. Sumrra, Mamduh J. Aljaafreh, Sadaf Noreen, Abrar U. Hassan

{"title":"Machine Learning–Assisted Design of Ytterbium-Based Materials with Tunable Bandgaps and Enhanced Stability","authors":"Sajjad H. Sumrra, Mamduh J. Aljaafreh, Sadaf Noreen, Abrar U. Hassan","doi":"10.1007/s13538-025-01732-x","DOIUrl":"10.1007/s13538-025-01732-x","url":null,"abstract":"<div><p>This study presents a comprehensive machine learning (ML) investigation into the design of ytterbium (Yb)–based materials with tunable bandgaps and enhanced stability. A dataset of 2062 Yb-based compounds was compiled from the literature, featuring structural and electronic properties. Their descriptors are designed to calculate their bandgap values through quantum chemical studies. Out of various machine learning models, Random Forest and Decision Tree regression models produce the more accurate prediction for their predicted values. The feature importance analysis reveals that their HeavyAtomCount, AliphaticRings, Ar_Rings, and TPSA emerge as important descriptors to influence their bandgap and stability. Their stability analysis by their Convex Hull Diagrams identifies 73% of data within its stability boundary. Further insights are gained through their clustering analysis, utilizing K-means clustering (<i>k</i> = 4), t-SNE, and elbow methods. The results show 85% accuracy to predict their stability and reveal distinct their chemical profiles as stable, moderately stable, and less stable compounds. The current study design approach is supposed to enable the discovery of Yb-based compounds with their tailored properties, like their tunable bandgaps (0.5–4.5 eV) with their enhanced stability (> 70%). The study can provide insights for materials scientists to identify promising optoelectronic materials.</p></div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143553891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Wave Mode Occurrence Distribution Around Venus: A VEX Statistical Study

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-03-01 DOI: 10.1007/s13538-025-01723-y

Adriane Marques de Souza Franco, Isabela de Oliveira, Markus Fraenz, Ezequiel Echer, Mauricio José Alves Bolzan, João Carlos de Moura Castro Neto

{"title":"Wave Mode Occurrence Distribution Around Venus: A VEX Statistical Study","authors":"Adriane Marques de Souza Franco, Isabela de Oliveira, Markus Fraenz, Ezequiel Echer, Mauricio José Alves Bolzan, João Carlos de Moura Castro Neto","doi":"10.1007/s13538-025-01723-y","DOIUrl":"10.1007/s13538-025-01723-y","url":null,"abstract":"<div><p>In this work, plasma and magnetic field data from Venus Express (VEX) were analyzed through the entire mission span (2006-2014) in order to statistically study wave mode occurrence around Venus considering different solar wind conditions. The wave mode occurrence distribution in terms of solar activity (maxima and minimum periods), solar wind pressure, and interplanetary magnetic field (IMF) east-west component orientation (<span>(B_{y}>0)</span> and <span>(B_{y}<0)</span>) were computed. Our results reveal that mirror mode occurrence does not seems to be affected by changes in the analyzed parameters. The most significant influence was observed in the Alfvén mode by the solar wind dynamic pressure, which has its occurrence rate clearly increased, during periods of high solar wind dynamic pressure. The fast mode seems to be influenced by the three analyzed parameters and tends to occur more often during periods of positive IMF <span>(B_{y})</span> and high solar activity. Further, a higher occurrence of fast wave mode during enhanced dynamic pressure was observed, which may be related to KH instability.</p></div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143527654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

CP Violation Problem

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-03-01 DOI: 10.1007/s13538-025-01729-6

Nicolai Popov, William J. Briscoe, Igor Strakovsky

引用次数: 0

Design of all-Optical Transmission Gate Using Silicon Microring Resonator

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-02-27 DOI: 10.1007/s13538-025-01730-z

Jayanta Kumar Rakshit, Premkumar Selvam, Selvakumarasamy Kathirvelu, Sultan Mahaboob Basha, Kalimuddin Mondal, Vankadari Nagaraju, Bhaskarrao Yakkala, Manjur Hossain

{"title":"Design of all-Optical Transmission Gate Using Silicon Microring Resonator","authors":"Jayanta Kumar Rakshit, Premkumar Selvam, Selvakumarasamy Kathirvelu, Sultan Mahaboob Basha, Kalimuddin Mondal, Vankadari Nagaraju, Bhaskarrao Yakkala, Manjur Hossain","doi":"10.1007/s13538-025-01730-z","DOIUrl":"10.1007/s13538-025-01730-z","url":null,"abstract":"<div><p>Proposed manuscript includes the implementation of all-optical transmission gate employing silicon microring resonator. A replacement for traditional CMOS technology, large-scale optical integrated circuits are being considered due to the increasing need for ultra-fast terahertz data processing and transfer. In addition, energy-efficient circuits are becoming more and more crucial. The architecture is analyzed at about 260 Gbps using MATLAB. Networks for optical signal processing can be constructed using all-optical transmission gates as building blocks. Proposed transmission gate is also utilized in the design of a 2:1 multiplexer. The evaluation of a few performance-indicating variables includes “extinction ratio (ER)”, “contrast ratio (CR)”, “amplitude modulation (AM)”, “on–off ratio (OOR)”, and “relative eye opening”. At low average pump power of 1.18 mW, proposed model has high ER, CR, and OOR of 26.78, 31.39, and 36.8 dB, respectively. Computed AM is recorded as 0.22 dB. Optimized design parameters are chosen to utilize the design practically.</p></div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143513284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Synthesis and Characterization of Co-doped (Li/W) Distorted Perovskite Bismuth Manganite (Bi1/2Li1/2)(Mn1/2W1/2)O3 for Electronic Devices

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-02-27 DOI: 10.1007/s13538-025-01726-9

Sudhansu Sekhar Hota, Debasish Panda, R. N. P. Choudhary

{"title":"Synthesis and Characterization of Co-doped (Li/W) Distorted Perovskite Bismuth Manganite (Bi1/2Li1/2)(Mn1/2W1/2)O3 for Electronic Devices","authors":"Sudhansu Sekhar Hota, Debasish Panda, R. N. P. Choudhary","doi":"10.1007/s13538-025-01726-9","DOIUrl":"10.1007/s13538-025-01726-9","url":null,"abstract":"<div><p>In this paper, structural, surface, capacitive, and transport characteristics of newly designed co-doped (Li<sup>+</sup>/W<sup>6+</sup>) distorted perovskite bismuth manganite of a composition (Bi<sub>1/2</sub>Li<sub>1/2</sub>)(Mn<sub>1/2</sub>W<sub>1/2</sub>)O<sub>3</sub> have been reported. The structural analysis of the material using X-ray diffraction data determines distorted perovskite monoclinic structure with unit cell dimensions of <i>a</i> = 8.4642 Å, <i>b</i> = 12.5179 Å, <i>c</i> = 8.2215 Å, <i>V</i> = 869.04 Å<sup>3</sup>, and <i>β</i> = 93.96°. Analysis of vibrational molecular bands of Raman and Fourier transform infrared spectroscopy (FTIR) spectra shows the inclusion/doping of Li<sup>+</sup>/W<sup>6+</sup> ions in the parent compound (bismuth manganite). A detailed study of impedance spectroscopy data shows the existence of a non-Debye relaxation mechanism indicating negative temperature coefficient of resistance (NTCR) behavior in the compound. Conductivity analysis shed light on the existence of charge transport mechanism and correlated barrier hopping process in the material. The hysteresis loops suggest the existence of ferroelectric properties in the material. In conclusion, this synthesized material shows excellent potential (TCR = − 1.3%/°C) for temperature-based applications.</p></div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143513282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spin-Gapless Quaternary Heusler Alloys IrCoTiZ (Z = Si, Sn, Pb): Exploring New Opportunities in Spintronics, Optoelectronics, and Thermoelectrics

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-02-25 DOI: 10.1007/s13538-025-01725-w

A. Khatar, B. Bouadjemi, M. Houari, M. Matougui, T. Lantri, K. Kelifa-Kerfa, S. Bentata, S. Haid, M. H. Cherif, A. Messaoudi, S. Mesbah

{"title":"Spin-Gapless Quaternary Heusler Alloys IrCoTiZ (Z = Si, Sn, Pb): Exploring New Opportunities in Spintronics, Optoelectronics, and Thermoelectrics","authors":"A. Khatar, B. Bouadjemi, M. Houari, M. Matougui, T. Lantri, K. Kelifa-Kerfa, S. Bentata, S. Haid, M. H. Cherif, A. Messaoudi, S. Mesbah","doi":"10.1007/s13538-025-01725-w","DOIUrl":"10.1007/s13538-025-01725-w","url":null,"abstract":"<div><p>This study explores the structural, electrical, magnetic, optical, and thermoelectric properties of quaternary Heusler alloys IrCoTiZ (Z = Si, Sn, Pb) through first-principals calculations using Wien2K computational package. These materials exhibit strong potential for high-temperature spintronic applications, owing to the stability of their ferromagnetic phase, with predicted Curie temperatures surpassing room temperature. The electronic structure analysis indicates a semiconducting band gap in the spin-down channel, while the spin-up channel retains metallic behaviour. Notably, IrCoTiSi demonstrates high absorption in both the visible and ultraviolet regions, highlighting its potential for optoelectronic applications. Thermoelectric analysis indicates that IrCoTiPb and IrCoTiSn behave as p-type materials, whereas IrCoTiSi exhibits a mixed n-type and p-type character. Although the thermoelectric efficiency is moderate at low to mid-range temperatures, the unique combination of spin-gapless semiconducting properties in these alloys highlights their potential for advancing spintronics, optoelectronics, and thermoelectric applications.</p></div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143489499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Geometry Underlying of the Gauge Principle

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-02-24 DOI: 10.1007/s13538-024-01677-7

Andrés Fernando Castillo Ramírez, John Morales Aponte, Teirungumu Apolinar Torres Zalabata

引用次数: 0

Electrostatic Dust Modes in Magnetized Dusty Plasma with Crucial Condition of Dust Lower Hybrid Mode

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-02-24 DOI: 10.1007/s13538-025-01727-8

M. A. H. Talukder, M. K. Islam, M. S. Munir, M. Salahuddin

引用次数: 0

Mathematical Modelling on Pulsative MHD Blood Casson Nanofluid in Slip and Porous Capillaries for Nano-cryosurgery with Caputo-Fabrizio Approach 利用卡普托-法布里齐奥方法建立用于纳米冷冻手术的滑动和多孔毛细管中脉动 MHD 血液卡松纳米流体数学模型

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-02-22 DOI: 10.1007/s13538-025-01701-4

Wan Faezah Wan Azmi, Ahmad Qushairi Mohamad, Lim Yeou Jiann, Sharidan Shafie

{"title":"Mathematical Modelling on Pulsative MHD Blood Casson Nanofluid in Slip and Porous Capillaries for Nano-cryosurgery with Caputo-Fabrizio Approach","authors":"Wan Faezah Wan Azmi, Ahmad Qushairi Mohamad, Lim Yeou Jiann, Sharidan Shafie","doi":"10.1007/s13538-025-01701-4","DOIUrl":"10.1007/s13538-025-01701-4","url":null,"abstract":"<div><p>Nano-cryosurgery is a novel approach to treating tumours that integrates cryosurgery and nanotechnology. Researchers are interested in nano-cryosurgery since it minimises damage to healthy surrounding tissue, bleeding, and post-surgery complications. However, conducting experimental research requires a lot of time and money. Hence, the mathematical model developed for blood flow with nanoparticles is significant for nano-cryosurgical treatments. The present study aims to investigate analytically the fractional derivative approach of blood nanofluid flow in the porous medium of a slip cylinder. The effects of pulsatile pressure gradient, MHD, and free convection flow are being considered. Blood nanofluid is modelled with a Casson fluid model dispersed with gold nanoparticles. The Caputo-Fabrizio fractional derivative approach, known for its dimensional consistency through normalisation, is employed in the momentum and energy equations. Then, dimensionless governing equations are obtained by employing the dimensionless variables. The problem is solved by combining the Laplace and finite Hankel transforms to obtain velocity and temperature expressions. The present study graphically illustrates and discusses the effects of various related parameters on the velocity and temperature profiles. The research findings revealed that the slip velocity significantly impacts the blood nanofluid flow at the cylinder’s wall. The fractional model of blood nanofluid is more sensible and accurate than the classical model. The results are essential for optimising the nano-cryosurgery procedure by controlling the ice formation and orientation, heat transfer mechanism between cryoprobe and cells, cryogenic agent delivery, and freezing and thawing time.</p></div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143471846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0