Brazilian Journal of Physics最新文献_第2页

On the Dynamics of COVID-19 Propagation with Vaccination and Optimal Control Strategies 论接种疫苗后 COVID-19 传播的动力学和最佳控制策略

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-04-15 DOI: 10.1007/s13538-025-01769-y

Padma Bhushan Borah, Dipika Robidas, Kaushik Dehingia, Bhagya Jyoti Nath, Hemanta Kumar Sarmah

{"title":"On the Dynamics of COVID-19 Propagation with Vaccination and Optimal Control Strategies","authors":"Padma Bhushan Borah, Dipika Robidas, Kaushik Dehingia, Bhagya Jyoti Nath, Hemanta Kumar Sarmah","doi":"10.1007/s13538-025-01769-y","DOIUrl":"10.1007/s13538-025-01769-y","url":null,"abstract":"<div>In this paper, a mathematical model is proposed to describe the spread dynamics of COVID-19, considering the factors of self-protection and vaccination. The basic reproduction number of the model, which is a critical signal of the dynamics of COVID-19 transmission, is calculated using the next-generation matrix method. A study of the local stability of steady states has been conducted. Moreover, global stability is demonstrated using Lyapunov’s second method and LaSalle’s invariance principle. In addition, the effect of vaccination on the evolution of the disease spread has been studied. Further, an optimal control problem is formulated and solved to reduce the number of infected individuals and the cost of the controls by considering self-protection and vaccination as intervention options. Specifically, our results indicate that implementing optimal control strategies, such as time-dependent interventions, reduces disease transmission and overall infection burden. The model demonstrates that strategically timed and intensity-optimized control measures can flatten the epidemic curve, delay peak infection, and minimize the outbreak’s cost and duration. Finally, comprehensive simulations were performed across various initial conditions and parameter settings to verify the theoretical findings.</div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s13538-025-01769-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143835658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dynamics of Polarized Ion-Acoustic Waves in Magnetized Degenerate Multi Ions Plasma with Trapped Electrons: Nonlinear Periodic and Superperiodic Waves 磁化去极化多离子等离子体中的极化离子声波动力学：非线性周期波和超周期波

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-04-15 DOI: 10.1007/s13538-025-01749-2

A. Atteya, Reem Altuijri, Kottakkaran Sooppy Nisar, Abdel-Haleem Abdel-Aty, P. K. Karmakar, Eman Mohammed El-Bayoumi

{"title":"Dynamics of Polarized Ion-Acoustic Waves in Magnetized Degenerate Multi Ions Plasma with Trapped Electrons: Nonlinear Periodic and Superperiodic Waves","authors":"A. Atteya, Reem Altuijri, Kottakkaran Sooppy Nisar, Abdel-Haleem Abdel-Aty, P. K. Karmakar, Eman Mohammed El-Bayoumi","doi":"10.1007/s13538-025-01749-2","DOIUrl":"10.1007/s13538-025-01749-2","url":null,"abstract":"<div>The modified Zakharov-Kuznetsov equation for ion-acoustic waves was developed using the reductive perturbation method in a multi-ion plasma system consisting of inertial ions that are both negatively and positively charged, as well as positively charged immobile heavy ions and electrons that are trapped in the presence of a quantizing magnetic field. Depending on the system’s characteristics, we looked at bifurcation analysis. All conceivable phase pictures, including periodic, homoclinic, and superperiodic trajectories, are shown. The occurrence of rarefactive and compressive solitary waves is demonstrated. The finite degenerate temperature, polarization parameter, and plasma particle number densities, charges, and masses all substantially influence these solitons. Furthermore, the plasma system under investigation might accommodate both nonlinear and superlinear periodic waves. The current discoveries are thought to be useful in comprehending the solitary structures in dense quantum plasmas like those seen in white dwarfs.</div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143835657","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

Laser-Induced Terahertz Radiation Generation in Magnetized QMCNT-Based Plasma 磁化qmcnt等离子体中激光诱导太赫兹辐射的产生

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-04-10 DOI: 10.1007/s13538-025-01767-0

Atal Bharati, Sandeep Kumar, Vishal Thakur

{"title":"Laser-Induced Terahertz Radiation Generation in Magnetized QMCNT-Based Plasma","authors":"Atal Bharati, Sandeep Kumar, Vishal Thakur","doi":"10.1007/s13538-025-01767-0","DOIUrl":"10.1007/s13538-025-01767-0","url":null,"abstract":"Laser-induced THz radiation generation by beating two collinear Gaussian laser beams of slightly different frequencies (({upomega }_{1},{upomega }_{2})) and wave number (({mathrm{k}}_{1}),({mathrm{k}}_{2})) copropagating through the array of quasi metallic carbon nanotube (QMCNT)-based plasma in an externally applied static magnetic field is proposed and investigated. An array of QMCNTs has been magnetized by applying a static magnetic field perpendicular to the direction of propagation of collinear Gaussian laser beams and along the length of QMCNTs. Collinear Gaussian laser beams interact with the atoms in QMCNT-based plasma, where the electrons of QMCNTs absorb the photon energy from the laser beams. Under the influence of laser fields and space charge fields, plasma electrons oscillate with an oscillatory velocity. When this oscillatory motion interacts with an external static magnetic field, a ponderomotive force is exerted on the electrons at the beat frequency. In the presence of nonlinear ponderomotive force, the oscillatory electrons of plasma electrons generate a non-linear current that subsequently leads to THz radiation generation. A static magnetic field applied externally within the range of 280 to 380 kG enhances the efficiency of normalized THz power by stabilizing plasma and amplifying its nonlinearity. Furthermore, the resonantly enhanced THz power occurs at a specific value of dimensions, i.e., length and width of QMCNTs. The impact of collision frequency on the amplitude and position of side peaks, which arise alongside the prominent resonance peak, is also explored. Our numerically analyzed scheme presents an efficient method for generating THz radiation, with applications in imaging, security scanning, and non-destructive testing.","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143818109","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

Integrated Analytical Techniques for Assessment of TiO2 Nanoparticles in Consolidation Treatment of Green and Red Pigments Based on a Greco-Roman Polychrome Case Study 基于古罗马多色的绿色和红色颜料固结处理中TiO2纳米颗粒的综合分析技术评价

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-04-09 DOI: 10.1007/s13538-025-01763-4

Hasnaa A. M. Abdrabbo, Ayman M. Mostafa, Mohamed A. Etman, Mohamed M. ElFaham, Maria Laura Santarelli, Hala A. M. Afifi

{"title":"Integrated Analytical Techniques for Assessment of TiO2 Nanoparticles in Consolidation Treatment of Green and Red Pigments Based on a Greco-Roman Polychrome Case Study","authors":"Hasnaa A. M. Abdrabbo, Ayman M. Mostafa, Mohamed A. Etman, Mohamed M. ElFaham, Maria Laura Santarelli, Hala A. M. Afifi","doi":"10.1007/s13538-025-01763-4","DOIUrl":"10.1007/s13538-025-01763-4","url":null,"abstract":"<div>Nanomaterials have approved over the last few decades a pallet of applications in the field of conservation of cultural heritage and monuments; among these applications was the consolidation of painted surfaces, which usually suffer from different degradation aspects, especially in museums. Considering the efficiency of nanostructured materials concerning the traditional one, the present study aims to evaluate titanium dioxide nanostructured materials, TiO2, used as a consolidant for the green malachite and red cinnabar pigments, through a brushing technique on a mimic prepared experimental samples, based on a wooden polychrome statuette dated from the late period to the Greco-Roman period and stored at storage rooms of the Grand Egyptian Museum in Giza, Egypt. Multi-analytical and investigation techniques such as digital microscope, SEM–EDX, FTIR, Raman spectroscopy, and LIBS have been used to evaluate the efficiency and performance of the selected materials. The results showed that using the hybrid form consisting of TiO2 NPs with Klucel E gave good results with high penetration and least color change values, while using the inorganic form showed good results in consolidation but with higher color change value, especially in the red cinnabar pigment.</div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143809155","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

An Impact of Thickness on Structural, Optical, and Electrochromic Properties of WO3 Films Deposited by Sputtering for Smart Window Applications 厚度对智能窗溅射WO3薄膜结构、光学和电致变色性能的影响

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-04-09 DOI: 10.1007/s13538-025-01765-2

Kilari Naveen Kumar, Nithya G., Ashok Reddy G. V., Sheik Abdul Sattar, Sthuthi A., Dhanalakshmi Radhalayam, M. Anantha Sunil, P. Rosaiah, Nunna Guru Prakash, Musarat Amina, Tae Jo Ko

{"title":"An Impact of Thickness on Structural, Optical, and Electrochromic Properties of WO3 Films Deposited by Sputtering for Smart Window Applications","authors":"Kilari Naveen Kumar, Nithya G., Ashok Reddy G. V., Sheik Abdul Sattar, Sthuthi A., Dhanalakshmi Radhalayam, M. Anantha Sunil, P. Rosaiah, Nunna Guru Prakash, Musarat Amina, Tae Jo Ko","doi":"10.1007/s13538-025-01765-2","DOIUrl":"10.1007/s13538-025-01765-2","url":null,"abstract":"<div>DC magnetron sputtering (DCMS) was employed to deposit tungsten oxide (WO3) films on corning glass (CG) and fluorine-doped tin oxide (FTO) substrates. The influence of thickness variations on the film structure, surface morphology, optical properties, and electrochromic (EC) characteristics was explored using various analytical techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDX), ultraviolet–visible (Uv–Vis) spectroscopy, and cyclic voltammetry (CV). SEM analysis revealed that the thickness of the WO3- 4 film was around 500 nm. The films exhibited smooth surfaces with uniform distributions of small voids and grain clusters. XRD analysis confirmed the amorphous nature of the WO3 thin films. The optical properties of the WO3 films were evaluated using ultraviolet–visible-near-infrared spectroscopy. Films of varying thicknesses displayed different transmittance modulations between the bleached and colored states. The WO3- 2 films exhibited the highest transmittance modulation, reaching 81% at 600 nm. The lowest diffusion coefficient (8.97 × 10−9 cm2/C) was observed in WO3- 1, which also exhibited a coloring efficiency (CE) of 22 cm2. The CE values for WO3- 2, WO3- 3, and WO3- 4 were 38 cm2/C, 40 cm2/C, and 16 cm2/C, respectively. This study highlighted the significant impact of film thickness on color efficiency, which is a crucial factor in electrochromic (EC) applications.</div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143809156","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

Optimization and Measurement of a 6G Terahertz Filter Based on the Multi-band Tunable Metasurface and Its Sensing 基于多波段可调谐超表面及其传感的6G太赫兹滤波器的优化与测量

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-04-05 DOI: 10.1007/s13538-025-01757-2

Jianfang Deng, Yegang Zhu, Rui Tian

引用次数: 0

Density Functional Theory Calculation on Electronic, Elastic, and Optical Properties of ZnIn2Te4 and HgIn2Te4 Defect-Chalcopyrite Semiconductors Under Different Pressures 不同压力下ZnIn2Te4和HgIn2Te4缺陷-黄铜矿半导体电子、弹性和光学性质的密度泛函理论计算

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-04-05 DOI: 10.1007/s13538-025-01764-3

S. Chandra, R. Santosh, S. Saha, G. D. Bharti, V. Kumar

{"title":"Density Functional Theory Calculation on Electronic, Elastic, and Optical Properties of ZnIn2Te4 and HgIn2Te4 Defect-Chalcopyrite Semiconductors Under Different Pressures","authors":"S. Chandra, R. Santosh, S. Saha, G. D. Bharti, V. Kumar","doi":"10.1007/s13538-025-01764-3","DOIUrl":"10.1007/s13538-025-01764-3","url":null,"abstract":"<div>Electronic, elastic, and optical properties of defect-chalcopyrite semiconductors ZnIn2Te4 and HgIn2Te4 were investigated through density functional theory calculations employing the local density approximation (LDA). The computed energy bandgaps for ZnIn2Te4 and HgIn2Te4 are 1.398 eV and 1.101 eV, respectively, revealing an indirect bandgap behavior. Elastic parameters and Debye temperature were examined under pressures of 0, 5, 10, 13, and 14 GPa. Results suggest that both semiconductors exhibit covalent behavior at 0 GPa, transitioning to ionic behavior at higher pressures. Optical parameters were also analyzed within an energy range of 0 eV to 15 eV under pressures of 0, 5, 10, and 13 GPa. The calculations indicate mechanical stability for these semiconductors up to 13 GPa, becoming unstable at 14 GPa. Comparison with available experimental and reported data at 0 GPa demonstrates reasonable agreement. Furthermore, this study provides the values of these parameters at 5, 10, 13, and 14 GPa pressures for the first time.</div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143784209","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

On the Characterization of a “Campo del Cielo” Meteorite Using Photon Energy Interaction and Radiation Absorption Parameters 利用光子能量相互作用和辐射吸收参数表征“Campo del Cielo”陨石

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-04-03 DOI: 10.1007/s13538-025-01762-5

Karuane S. Kodum, Antonio Liccardo, Sérgio C. Saab, André M. Brinatti, Luiz F. Pires

{"title":"On the Characterization of a “Campo del Cielo” Meteorite Using Photon Energy Interaction and Radiation Absorption Parameters","authors":"Karuane S. Kodum, Antonio Liccardo, Sérgio C. Saab, André M. Brinatti, Luiz F. Pires","doi":"10.1007/s13538-025-01762-5","DOIUrl":"10.1007/s13538-025-01762-5","url":null,"abstract":"<div>Research on the impact of meteorite chemical composition on radiation interaction parameters is scarce. Understanding how photons of varying energies interact with meteorites is fundamental to grasp these extraterrestrial bodies and facilitate future space missions. Our research utilized scanning electron microscopy and X-ray fluorescence techniques to analyze the elemental composition of meteorites found in the regions called “Campo del Cielo,” in Argentina. Scientists discovered the second heaviest meteorite in this planetary region, composed primarily of Fe and Ni, which comprise over 95% of its chemical composition based on our results. The meteorite fragments studied presented Fe and Ni contents ranging from 88.55 to 93.56% and 5.55 to 7.24%, respectively. This result confirms that the meteorite studied belongs to the IAB Og group. No differences were observed in the attenuation coefficient or in the atomic and electronic cross-sections due to variations in photon energy. Similarities in the chemical composition of the fragment samples explain this result. The molecular cross-section was more sensitive to differences in the chemical composition of the samples, mainly influenced by the dependence of this parameter on the molecular weight of the elements of the fragment studied. The effective atomic number and electronic density were also sensitive to the chemical composition of the samples, mainly due to the Ni content. The fact that the meteorite studied is mostly made of Fe and Ni shows that this material has a high capacity for attenuating radiation and can effectively shield radiation. This result could be of great interest, especially in future space missions when materials found in space could be used to provide protection against radiation.</div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143769767","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

Experimental and Theoretical Studies on a New Urea Clathrate Crystal: X-ray Diffraction, Hirshfeld Surface Analysis, RDG − NCI, FMOs, and NBO Analysis 一种新型尿素包合物晶体的实验与理论研究：x射线衍射、Hirshfeld表面分析、RDG - NCI、FMOs和NBO分析

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-04-03 DOI: 10.1007/s13538-025-01753-6

Wardha Zafar, Sadaf Noreen, Ashraf Y. Elnaggar, Mohamed H. H. Mahmoud, Islam H. El Azab

{"title":"Experimental and Theoretical Studies on a New Urea Clathrate Crystal: X-ray Diffraction, Hirshfeld Surface Analysis, RDG − NCI, FMOs, and NBO Analysis","authors":"Wardha Zafar, Sadaf Noreen, Ashraf Y. Elnaggar, Mohamed H. H. Mahmoud, Islam H. El Azab","doi":"10.1007/s13538-025-01753-6","DOIUrl":"10.1007/s13538-025-01753-6","url":null,"abstract":"<div>In this study, a urea clathrate (UC) crystal structure was successfully grown and analyzed using single-crystal–X-ray diffraction (SC − XRD) and computational methods. After a slow evaporation period of 20 days, the crystal adopts a tetrahedral geometry within the P − 421 m space group. Their Hirshfeld surface analysis reveals that their O − H (~ 31.3%) and C − H (~ 29.3%) interactions may be the key players in stabilizing its geometry. Crystallographic Information File (CIF) is used as an input file for computational approaches to investigate its theoretical interactions with tobacco alkaloids. Its density of states (DOS) by its optimized geometries shows that it maintains a distance ~ 2.82 − 3.16 Å from these alkaloids while it also demonstrates an excellent recovery time of ~ 2.89 × 10−19 s. Their molecular charges have suggested that the charge mostly concentrates over the alkaloids. Its Natural Bond Orbital (NBO) analysis highlights key transitions, notably the strong hyperconjugation between (C1 − C2)π → (C1 − C7) π* (1.15 kcal/mol) and (N4)π → (C1 − C2)π* (5.93 kcal/mol), influencing its electronic structure and reactivity.</div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143769769","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

Enhanced Malaria Detection Using a Hybrid Borophene-Based Terahertz Biosensor with Random Forest Regression Analysis 基于随机森林回归分析的混合硼罗芬太赫兹生物传感器增强疟疾检测

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2025-04-03 DOI: 10.1007/s13538-025-01759-0

Jacob Wekalao, Stephen Maina Njoroge, Oumaymah Elamri

引用次数: 0