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Impact of device resistances in the performance of graphene‑based terahertz photodetectors

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Frontiers of optoelectronics 2024年第2期17卷 87-97页

作者： o.Castelló Sofía m.López Baptista K.Watanabe T.Taniguchi E.Diez j.E.Velázquez-Pérez y.m.meziani j.m.Caridad j.A.Delgado-Notario Department of Applied Physics University of Salamanca37008 SalamancaSpain Unidad de Excelencia en Luz y materia Estructurada(LUmES) University of Salamanca37008 SalamancaSpain Research Center for Electronic and optical materials National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Research Center for materials Nanoarchitectonics National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Nanotechnology Group USAL-NanolabUniversity of Salamanca37008 SalamancaSpain

In recent years,graphene field-effect-transistors(GFETs)have demonstrated an outstanding potential for terahertz(THz)photodetection due to their fast response and *** features are essential to enable emerging THz applications,including 6G wireless communications,quantum information,bioimaging and ***,the overall performance of these photodetectors may be utterly compromised by the impact of internal resistances presented in the device,so-called access or parasitic *** this work,we provide a detailed study of the influence of internal device resistances in the photoresponse of high-mobility dual-gate GFET *** dual-gate architectures allow us to fine tune(decrease)the internal resistance of the device by an order of magnitude and consequently demonstrate an improved responsivity and noise-equivalent-power values of the photodetector,*** results can be well understood by a series resistance model,as shown by the excellent agreement found between the experimental data and theoretical *** findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene photodetectors.

关键词： Graphene THz Photodetector Field-effect transistor Plasmonic

Europium recovery process by means of polymeric nanoparticles functionalized with acrylic acid,curcumin and fumaramide

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journal of Rare Earths 2024年第10期42卷 1950-1959页

作者： P.A.martínez-montoya j.m del Río A.de j.morales-Ramirez m.Corea Escuela Superior de Ingeniería Química e Industrias Extractivas ESIQIE-IPNDepartamento de Ingeniería Metalúrgica UPALM S/N Col.LindavistaGustao A.MaderoCDMXC.P.07738Mexico Escuela Superior de Ingenieria Química e Industrias Extractivas ESIQIE-IPNLaboratorio de Investigación en Polímeros y NanomaterialesUPALM S/N Col.LindavistaGustavoA.MaderoCDMXC.P.07738Mexico Centra de Investigación e Innovación Tecnológica CIITEC-IPNCda.de CECATIs/nSanta CatarinaAzcapotzalcoC.P.02250CDMXMexico

Polymeric nanoparticles of poly(methyl methacrylate)were obtained by emulsion polymerization techniques in a proce ss of two *** particles were functionalized with acrylic acid,curcumin,and fumaramide and three series of polymeric particles were *** incorporation of functional groups was confirmed by Fourier transform-infrared spectrosocopy(FT-IR)and ultraviolet-visible(UV-Vis)*** spherical morphology of particles with an average diameter of 100 nm was observed by scartning electron microscopy(SEm).The polymeric materials were used for recovery of[Eu]from synthetic *** nanoparticles show excellent chelation capacity to trap rare-earth ions,because they recover more than 85%of[Eu]at pH of *** images of SEm after extraction process show arrays between particles with larger average particle sizes to 1.5 *** addition,the particles have a good stripping capacity,exceeding 50%of it,maintaining their homogeneity in morphology and good stability in dispersion for the recovery and stripping processes.A pseudo-second model order is obtained for the extraction and stripping processes while the best results of stripping process are obtained at pH of 6.

关键词： [Eu]recovery Chelating effect Extraction process Stripping process Emulsion polymerization Rare earths

message Verification Protocol Based on Bilinear Pairings and Elliptic Curves for Enhanced Security in Vehicular Ad Hoc Networks

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Computers, materials and Continua 2024年第1期81卷 1029-1057页

作者： Nyangaresi V.o. Ghaib A.A. jasim H.m. Abduljabbar Z.A. ma j. Al Sibahee m.A. Aldarwish A.j.y. Ali A.H. Neamah H.A. Department of Computer Science and Software Engineering Jaramogi Oginga Odinga University of Science and Technology Bondo 40601 Kenya Department of Applied Electronics Saveetha School of Engineering SIMATS Tamilnadu Chennai 602105 India Information Technology Department Management Technical College Southern Technical University Basrah 61004 Iraq Department of Computer Science College of Education for Pure Sciences University of Basrah Basrah 61004 Iraq College of Big Data and Internet Shenzhen Technology University Shenzhen 518118 China Huazhong University of Science and Technology Shenzhen Institute Shenzhen 518000 China National Engineering Laboratory for Big Data System Computing Technology Shenzhen University Shenzhen 518060 China Computer Technology Engineering Department Iraq University College Basrah 61004 Iraq Department of mathematics College of Education for Pure Sciences University of Basrah Basrah 61004 Iraq Institute of mathematics University of Debrecen Debrecen H-4002 Hungary Department of Electrical Engineering and mechatronics Faculty of Engineering University of Debrecen Debrecen 4028 Hungary

Vehicular ad hoc networks (VANETs) provide intelligent navigation and efficient route management, resulting in time savings and cost reductions in the transportation sector. However, the exchange of beacons and messages over public channels among vehicles and roadside units renders these networks vulnerable to numerous attacks and privacy violations. To address these challenges, several privacy and security preservation protocols based on blockchain and public key cryptography have been proposed recently. However, most of these schemes are limited by a long execution time and massive communication costs, which make them inefficient for on-board units (oBUs).Additionally, some of them are still susceptible tomany *** such, this study presents a novel protocol based on the fusion of elliptic curve cryptography (ECC) and bilinear pairing (BP) operations. The formal security analysis is accomplished using the Burrows-Abadi-Needham(BAN) logic, demonstrating that our scheme is verifiably secure. The proposed scheme's informal security assessment also shows that it provides salient security features, such as non-repudiation, anonymity, and unlinkability. moreover, the scheme is shown to be resilient against attacks, such as packet replays, forgeries,message falsifications, and impersonations. Fromthe performance perspective, this protocol yields a 37.88% reduction in communication overheads and a 44.44% improvement in the supported security features. Therefore, the proposed scheme can be deployed in VANETs to provide robust security at low overheads. © 2024 The Authors. Published by Tech Science Press.

关键词： Attacks bilinear elliptic curve cryptography (ECC) privacy security vehicular ad hoc network (VANET)

Greatly enhanced corrosion/wear resistances of epoxy coating for mg alloy through a synergistic effect between functionalized graphene and insulated blocking layer

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journal of magnesium and Alloys 2024年第1期12卷 332-344页

作者： Z.y.Xue X.j.Li j.H.Chu m.m.Li D.N.Zou L.B.Tong School of metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China State Key Laboratory of Advanced Design and manufacturing for Vehicle Body Hunan UniversityChangsha 410082China

The poor corrosion and wear resistances of mg alloys seriously limit their potential applications in various *** conventional epoxy coating easily forms many intrinsic defects during the solidification process,which cannot provide sufficient *** the current study,we design a double-layer epoxy composite coating on mg alloy with enhanced anti-corrosion/wear properties,via the spin-assisted assembly *** outer layer is functionalized graphene(FG)in waterborne epoxy resin(WEP)and the inner layer is Ce-based conversion(Ce)*** FG sheets can be homogeneously dispersed within the epoxy matrix to fill the intrinsic defects and improve the barrier *** Ce film connects the outer layer with the substrate,showing the transition *** corrosion rate of Ce/WEP/FG composite coating is 2131 times lower than that of bare mg alloy,and the wear rate is decreased by~90%.The improved corrosion resistance is attributed to the labyrinth effect(hindering the penetration of corrosive medium)and the obstruction of galvanic coupling *** synergistic effect derived from the FG sheet and blocking layer exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of mg alloys.

关键词： mg alloy Functionalized graphene Epoxy coating Corrosion/wear resistance Blocking layer

Influence of the zigzag fins and inlet arrangements on the cooling proficiency of the mini-channel heat sink

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Propulsion and Power Research 2024年第2期13卷 194-206页

作者： A.Torbatinezhad y.Pahamli m.j.Hosseini R.Bahrampoury School of mechanical Engineering Babol University of TechnologyBabolIran Department of mechanical Engineering Semnan UniversitySemnanIran Department of mechanical Engineering Faculty of EngineeringGolestan UniversityGorganIran Department of mechanical Engineering K.N.Toosi University of TechnologyTehranIran

mini-channel heatsinks are one of the most effective thermal management methods for high heatﬂux devices due to the high performance of convective heat *** recent years,various techniques have been innovated to improve the thermal proﬁciency of the mini-channel *** of these are taking advantage ofﬁns’structural designs and ar-rangements of inlets and *** zigzagﬁns and channels were considered in the previous works in heatsinks,and researchers analyzed their cooling enhancement ***,in the present work,a combined cooling technique,considering new-type zigzagﬁns’geometrical parameters(arrangement,length,and height)causes turbulenceﬂow and higher convective heat transfer along with different positionings ofﬂow inlet and outlets resulting in superior temper-ature uniformity,is proposed to evaluate their impacts on the cooling proﬁciency of the heat sink versus different Reynolds *** assess the thermal and hydraulic performance of the proposed heatsink,different parameters,including temperature contours,Nusselt numbers,thermal resistance,and entropy generation are *** a result,it is observed that in the case demonstrating the best thermal performance,the Nusselt number,pressure drop,thermal resistance,and entropy generation are respectively 37.13,4586.46 Pa,0.000078 m^(2)·K/W,and 0.1078 W/K in the best *** well,it is found that by changing the arrangements of inlets and outlets,the Nusselt number,and thermal resistance are improved by 12%and 13%,***,the proposed mini-channel heat sink could be used as a high-performance thermal management system for electronic devices in different industries,including energy,solar,and medical sectors.

关键词： Thermal management Heat transfer enhancement mini-channel heatsink Zigzagﬁn Entropy generation Electronic cooling

Interfacial stress engineering toward enhancement of ferroelectricity in Al doped Hfo_(2)thin films

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Chinese Physics B 2024年第9期33卷 637-643页

作者： S X Chen m m Chen y Liu D W Cao G j Chen Department of microelectronics Jiangsu UniversityZhenjiang 212013China Department of Physics Jiangsu UniversityZhenjiang 212013China Guangdong–Hong Kong–macao joint Laboratory for Intelligent micro-Nano optoelectronic Technology Foshan UniversityFoshan 528225China

Ferroelectric Hfo_(2)has attracted much attention owing to its superior ferroelectricity at an ultra-thin thickness and good compatibility with Si-based complementary metal-oxide-semiconductor(CmoS)***,the crystallization of polar orthorhombic phase(o-phase)Hfo_(2)is less competitive,which greatly limits the ferroelectricity of the as-obtained ferroelectric Hfo_(2)thin ***,the crystallization of o-phase Hfo_(2)can be thermodynamically modulated via interfacial stress *** this paper,the growth of improved ferroelectric Al doped Hfo_(2)(Hfo_(2):Al)thin films on(111)-oriented Si substrate has been *** analysis has suggested that nonpolar monoclinic Hfo_(2):Al grown on(111)-oriented Si substrate suffered from a strong compressive strain,which promoted the crystallization of(111)-oriented o-phase Hfo_(2)in the as-grown Hfo_(2):Al thin *** addition,the in-plane lattice of(111)-oriented Si substrate matches well with that of(111)-oriented o-phase Hfo_(2),which further thermally stabilizes the o-phase Hfo_(2).Accordingly,an improved ferroelectricity with a remnant polarization(2P_(r))of 26.7C/cm^(2) has been *** results shown in this work provide a simple way toward the preparation of improved ferroelectric Hfo_(2)thin films.

关键词： improved ferroelectricity interfacial stress engineering compressive strain Hfo_(2)

Energy and blast performance of beryllium in a model thermobaric composition in comparison with aluminum and magnesium

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Defence Technology（防务技术） 2024年第6期36卷 13-19页

作者： Thomas m.Klapotke Stanisław Cudziło Waldemar A.Trzcinski jozef Paszula Energetic materials Research Department of ChemistryUniversity of Munich(LMU)Butenandtstrasse 5-13(D)81377MunichGermany military University of Technology Faculty of Advanced Technologies and ChemistrySylwester Kaliski Str.200-908WarsawPoland

A direct comparison is made between the effectiveness of Al,mg,and Be powders as additional fuels in model thermobaric compositions containing 20%fuel,20%ammonium perchlorate,and 60%RDX(1,3,5-Trinitro-1,3,5-triazacyclohexane)passivated with *** determined calorimetric measurements of the heat of detonation,along with the overpressure histories in an explosion chamber filled with nitrogen,were used to determine the quasi-static pressure(QSP)under anaerobic *** measurements were also performed in a semi-closed bunker,and all blast wave parameters generated after the detonation of 500 g charges of the tested explosives were *** calorimetry results,QSP values,and blast wave parameters(pressure amplitude,specific and total impulses)clearly indicate that Be is much more effective as an additional fuel than either Al or mg in both anaerobic post-detonation reactions as well as the subsequent aerobic *** heat of detonation of the RDXwax/AP/Be explosive mixture is over 40%and 50%higher than that of the mixture containing aluminum and magnesium instead of beryllium,***,the TNT equivalent of the Be-containing composition due to the overpressure in the nitrogen-filled explosion chamber is 1.66,while the equivalent calculated using an air shock wave-specific impulse at a distance of 2.5 m is equal to *** high values of these parameters confirm the high reactivity of beryllium in both the anaerobic and aerobic stages of the thermobaric explosion.

关键词： Thermobaric explosives Beryllium Heat of detonation Quasi-static overpressure Blast wave parameters

Effect of Al_(2)o_(3)on the mechanical Properties of(B_(4)C+Al_(2)o_(3))/Al Neutron Absorbing materials

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Acta metallurgica Sinica(English Letters) 2024年第8期37卷 1411-1420页

作者： j.X.Cai B.m.Shi N.Li y.Liu Z.G.Zhang y.N.Zan Q.Z.Wang B.L.Xiao Z.y.ma Shi‑Changxu Innovation Center for Advanced materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key Laboratory of Nuclear materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing 100840China Department of materials Science School of Mechanical EngineeringShenyang UniversityShenyang 110044China

B_(4)C/Al composites are widely utilized as neutron absorbing materials for the storage and transportation of spent nuclear *** order to improve the high-temperature mechanical properties of B_(4)C/Al composites,in-situ nano-Al_(2)o_(3)was introduced utilizing oxide on Al powder *** this study,the Al_(2)o_(3)content was adjusted by utilizing spheroid Al powder with varying diameters,thereby investigating the impact of Al_(2)o_(3)content on the tensile properties of(B_(4)C+Al_(2)o_(3))/Al *** was found that the pinning effect of Al_(2)o_(3)on the grain boundaries could hinder the recovery of dislocations and lead to dislocation accumulation at high *** the result,with the increase in Al_(2)o_(3)content and the decrease in grain size,the high-temperature strength of the composites increased *** finest Al powder used in this investigation had a diameter of 1.4μm,whereas the resultant composite exhibited a maximum strength of 251 mPa at room temperature and 133 mPa at 350℃,surpassing that of traditional B_(4)C/Al composites.

关键词： Al matrix composites Neutron absorbing materials (B_(4)C+Al_(2)o_(3))/Al composites High-temperature strength

Deploying Hybrid Ensemblemachine Learning Techniques for Effective Cross-Site Scripting (XSS) Attack Detection

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Computers, materials and Continua 2024年第1期81卷 707-748页

作者： Bacha N.U. Lu S. Ur Rehman A. Idrees m. Ghadi y.y. Alahmadi T.j. School of Cyber Science and Engineering Huazhong University of Science and Technology Wuhan 430073 China Department of Computer Science and Engineering University of Engineering and Technology Lahore 54000 Pakistan Department of Computer Science and Software Engineering Al Ain University Al Ain Abu Abu Dhabi 12555 United Arab Emirates Department of Information Systems College of Computer and Information Sciences Princess Nourah bint Abdulrahman University Riyadh 84428 Saudi Arabia

Cross-Site Scripting (XSS) remains a significant threat to web application security, exploiting vulnerabilities to hijack user sessions and steal sensitive data. Traditional detection methods often fail to keep pace with the evolving sophistication of cyber threats. This paper introduces a novel hybrid ensemble learning framework that leverages a combination of advanced machine learning algorithms-Logistic Regression (LR), Support Vector machines (SVm), eXtreme Gradient Boosting (XGBoost), Categorical Boosting (CatBoost), and Deep Neural Networks (DNN). Utilizing the XSS-Attacks-2021 dataset, which comprises 460 instances across various real-world trafficrelated scenarios, this framework significantly enhances XSS attack detection. our approach, which includes rigorous feature engineering and model tuning, not only optimizes accuracy but also effectively minimizes false positives (FP) (0.13%) and false negatives (FN) (0.19%). This comprehensive methodology has been rigorously validated, achieving an unprecedented accuracy of 99.87%. The proposed system is scalable and efficient, capable of adapting to the increasing number of web applications and user demands without a decline in performance. It demonstrates exceptional real-time capabilities, with the ability to detect XSS attacks dynamically, maintaining high accuracy and low latency even under significant loads. Furthermore, despite the computational complexity introduced by the hybrid ensemble approach, strategic use of parallel processing and algorithmtuning ensures that the system remains scalable and performs robustly in real-time applications. Designed for easy integration with existing web security systems, our framework supports adaptable Application Programming Interfaces (APIs) and a modular design, facilitating seamless augmentation of current defenses. This innovation represents a significant advancement in cybersecurity, offering a scalable and effective solution for securing modern web applications a

关键词： Cross-site scripting hybrid learning machine learning stacking ensemble learning XSS detection