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Journal of Rare Earths 2024年第7期42卷 1344-1353,I0006页

作者： Mohsen Choupani ahmad Gholizadeh School of Physics Damghan UniversityDamghan36716-45667Iran

The doping of the spinel ferrites with selective cations usually improves the properties of the parent *** effect of Co^(2+)/Gd^(3+)co-substitution on the microstructure,optical,and magnetic properties of Cu1-xCoxFe2-xGdxO4 prepared by the citrate-nitrate auto-combustion synthesis was *** of the samples was performed with powder X-ray diffraction(XRD),Raman and Fouriertransform infrared(FTIR)spectroscopy,field-emission scanning electron microscopy,X-ray energydispersive spectroscopy,UV-Vis spectroscopy,and a vibrating sample *** results of XRD,Raman,and FTIR analysis show a gradual structural phase transition from a tetragonal(I41/amd)structure to a cubic(Fd3m)*** bandgap energy of the studied samples is in a range of 1.57-1.75 eV with a minimum in sample x=0.06 and then *** investigations show that the presence of Co^(2+)/Gd^(3+)cations in an octahedral site of the copper ferrite structure could increase saturation magnetization and coercive field from 567.9 Oe and 23.62 emu/g to 929.4 Oe and 28.27 emu/g,respectively.

关键词： Spinel copper ferrite Citrate-nitrate method Structure phase transition Microstructure properties Magnetic properties Rare earths

Probing the Efficiency of PPMG-Based Composite Electrolytes for Applications of Proton Exchange Membrane Fuel Cell

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Transactions of Tianjin University 2024年第3期30卷 262-283页

作者： Shakeel Ahmed Faizah Altaf Safyan Akram khan Sumaira Manzoor Aziz ahmad Muhammad Mansha Shahid Ali Ata-ur-Rehman Karl Jacob School of Material Science and Engineering Henan International Joint Laboratory of Nano-Photoelectric Magnetic MaterialsHenan University of TechnologyZhengzhou 450001China Interdisciplinary Research Center for Hydrogen Technologies and Carbon Management King Fahd University of Petroleum and Minerals31261 DhahranSaudi Arabia School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

PPMG-based composite electrolytes were fabricated via the solution method using the polyvinyl alcohol and polyvinylpyrrolidone blend reinforced with various contents of sulfonated inorganic *** acid was employed as the sulfonating agent to functionalize the external surface of the inorganic filler,i.e.,graphene *** proton conductivities of the newly prepared proton exchange membranes(PEMs)were increased by increasing the temperature and content of sulfonated graphene oxide(SGO),i.e.,ranging from 0.025 S/cm to 0.060 S/*** induction of the optimum level of SGO is determined to be an excellent route to enhance ionic *** single-cell performance test was conducted by sandwiching the newly prepared PEMs between an anode(0.2 mg/cm^(2) Pt/Ru)and a cathode(0.2 mg/cm^(2) Pt)to prepare membrane electrode assemblies,followed by hot pressing under a pressure of approximately 100 kg/cm^(2) at 60℃for 5–10 *** highest power densities achieved with PPMG PEMs were 14.9 and 35.60 mW/cm^(2) at 25℃and 70℃,respectively,at ambient pressure with 100%relative *** showed that the newly prepared PEMs exhibit good electrochemical *** results indicated that the prepared composite membrane with 6 wt%filler can be used as an alternative membrane for applications of high-performance proton exchange membrane fuel cell.

关键词： Proton exchange membrane fuel cell Sulfonated graphene oxide Polyvinylpyrrolidone Solution casting Membrane electrode assembly Fuel cell performance

A novel medical image data protection scheme for smart healthcare system

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CAAI Transactions on Intelligence Technology 2024年第4期9卷 821-836页

作者： Mujeeb Ur Rehman Arslan Shafique Muhammad Shahbaz khan Maha Driss Wadii Boulila Yazeed Yasin Ghadi Suresh Babu Changalasetty Majed Alhaisoni Jawad ahmad School of Computer Science and Informatics Cyber Technology InstituteDe Montfort UniversityLeicesterUK Department of Biomedical Engineering University of GlasgowGlasgowUK School of Computing Engineering and the Built EnvironmentEdinburgh Napier UniversityEdinburghUK Robotics and Internet‐of‐Things Laboratory Prince Sultan UniversityRiyadhSaudi Arabia Department of Computer Science Al Ain UniversityAl AinUnited Arab Emirates Department of Computer Engineering College of Computer Science King Khalid UniversityAbhaSaudi Arabia Computer Sciences Department College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadhSaudi Arabia

The Internet of Multimedia Things(IoMT)refers to a network of interconnected multimedia devices that communicate with each other over the ***,smart healthcare has emerged as a significant application of the IoMT,particularly in the context of knowledge‐based learning *** healthcare systems leverage knowledge‐based learning to become more context‐aware,adaptable,and auditable while maintain-ing the ability to learn from historical *** smart healthcare systems,devices capture images,such as X‐rays,Magnetic Resonance *** security and integrity of these images are crucial for the databases used in knowledge‐based learning systems to foster structured decision‐making and enhance the learning abilities of ***,in knowledge‐driven systems,the storage and transmission of HD medical images exert a burden on the limited bandwidth of the communication channel,leading to data trans-mission *** address the security and latency concerns,this paper presents a lightweight medical image encryption scheme utilising bit‐plane decomposition and chaos *** results of the experiment yield entropy,energy,and correlation values of 7.999,0.0156,and 0.0001,*** validates the effectiveness of the encryption system proposed in this paper,which offers high‐quality encryption,a large key space,key sensitivity,and resistance to statistical attacks.

关键词： data analysis medical image processing security

Evaluation of soil loss severity and ecological restoration approach for sustainable agriculture in the Hindu Kush, Karakoram and Himalaya region

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Journal of Mountain Science 2024年第5期21卷 1509-1521页

作者： Arshad ASHRAF Imran ahmad Climate Energy and Water Research InstituteNational Agricultural Research Centre(NARC)Islamabad 44000Pakistan

Soil erosion has resulted in removal of the topsoils containing fine soil particles and plant nutrients, causing decrease in soil fertility in the Hindu Kush, Karakoram and Himalaya(HKH) region. The existing production of cereal crop grains has been reduced to one third of the potential crop grains production owing to land degradation and poor farming practices. It is necessary to assess risk of soil loss and identify appropriate controlling measures to address issues of low agriculture productivity and water insecurity in the region. In the present study, severity of soil loss was predicted using Revised Universal Loss Equation(RUSLE) and ecological measures were identified for sustainable mountain agriculture in the HKH region of Upper Indus Basin, Pakistan. Overall 62.6% area was found to have very low risk of soil loss, i.e., 100 t/(ha·yr) in about 6.8% and 7.4% areas respectively. The mean rate of soil loss was about 41.9 t/(ha·yr) in the Hindu Kush, 31.1 t/(ha·yr) in the Himalayas, 18.8 t/(ha·yr) in the Karakoram and overall 29.7 t/(ha·yr) in the three HKH ranges. As such no considerable measures have been adopted by the communities for restoration of the degraded areas except raising fruit/farm trees and supporting limited social forestry for their livelihoods. The slopes cleared for cultivation and susceptible to erosion may be stabilized through sowing/planting of multi-purpose plant species and formation of proper bench terraces. The conservation of forest ecosystem and pastures at higher elevations would help in reducing overland water flow, risk of flash flood hazard and minimizing sediment loads in the downstream. It is essential to adopt site-specific resource conservation techniques and restore possible ecosystem health for sustainable agriculture and economic developm

关键词： Climate change Erodibility Indus basin Land degradation Slope stabilization

Suppression and synchronization of chaos in uncertain time-delay physical system

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 416-437页

作者： Israr ahmad Muhammad Shafiq Department of Preparatory Studies Centre University of Technology and Applied SciencesNizwaOman Department of Electrical and Computer Engineering Sultan Qaboos UniversityOman

The mechanical horizontal platform(MHP)system exhibits a rich chaotic *** chaotic MHP system has applications in the earthquake and offshore *** article proposes a robust adaptive continuous control(RACC)*** investigates the control and synchronization of chaos in the uncertain MHP system with time-delay in the presence of unknown state-dependent and time-dependent *** closed-loop system contains most of the nonlinear terms that enhance the complexity of the dynamical system;it improves the efficiency of the *** proposed RACC approach(a)accomplishes faster convergence of the perturbed state variables(synchronization errors)to the desired steady-state,(b)eradicates the effect of unknown state-dependent and time-dependent disturbances,and(c)suppresses undesirable chattering in the feedback control *** paper describes a detailed closed-loop stability analysis based on the Lyapunov-Krasovskii functional theory and Lyapunov stability *** provides parameter adaptation laws that confirm the convergence of the uncertain parameters to some constant *** computer simulation results endorse the theoretical findings and provide a comparative performance.

关键词： chaotic horizontal platform system chaos suppression chaos synchronization robust adaptive control Lyapunov stability theory

Malaysia-China Relations:Exemplary Model for ASEAN

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China Report ASEAN 2024年第6期9卷 48-51页

作者： Dato'Abdul Majid ahmad khan Malaysia-China Friendship Association

Five Decades(1974-2024)of Harmonious and Mutually Beneficial Partnership Fifty years ago in May 1974,the second Prime Minister of Malaysia,Tun Abdul Razak,journeyed to Beijing,China,to start a new and strategic chapter in Malaysia-China *** was a visionary and courageous initiative by Malaysia that commenced resetting Malaysia's foreign policy towards non-alignment and building mutual trust with China.

关键词： Malaysia mutual policy

Federated Learning Security and Privacy-Preserving Algorithm and Experiments Research Under Internet of Things Critical Infrastructure

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Tsinghua Science and Technology 2024年第2期29卷 400-414页

作者： Nasir ahmad Jalali Hongsong Chen Department of Computer Science University of Science and Technology Beijing(USTB)Beijing 100083China

The widespread use of the Internet of Things(IoTs)and the rapid development of artificial intelligence technologies have enabled applications to cross commercial and industrial band *** such systems,all participants related to commercial and industrial systems must communicate and generate ***,due to the small storage capacities of IoT devices,they are required to store and transfer the generated data to third-party entity called“cloud”,which creates one single point to store their ***,as the number of participants increases,the size of generated data also ***,such a centralized mechanism for data collection and exchange between participants is likely to face numerous challenges in terms of security,privacy,and *** address these challenges,Federated Learning(FL)has been proposed as a reasonable decentralizing approach,in which clients no longer need to transfer and store real data in the central ***,they only share updated training models that are trained over their private *** the same time,FL enables clients in distributed systems to share their machine learning models collaboratively without their training data,thus reducing data privacy and security ***,slow model training and the execution of additional unnecessary communication rounds may hinder FL applications from operating properly in a distributed ***,these unnecessary communication rounds make the system vulnerable to security and privacy issues,because irrelevant model updates are sent between clients and ***,in this work,we propose an algorithm for fully homomorphic encryption called Cheon-Kim-Kim-Song(CKKS)to encrypt model parameters for their local information privacy-preserving *** proposed solution uses the impetus term to speed up model convergence during the model training ***,it establishes a secure communication channel between IoT devices and the *** a

关键词： Federated Learning(FL) Internet of Things(IoTs) lightweight Transport Layer Security(iTLS) Cheon-Kim-Kim-Song(CKKS)

Analysis of cerium substitution in Co-Sr based spinel ferrites for high frequency application

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Journal of Rare Earths 2024年第9期42卷 1755-1763,I0005页

作者： Laura Khudaysh Inas A.Ahmed Syeda Rabia Ejaz Sajjad ahmad khan Yasir A.Haleem Mohamed M.Ibrahim Mahmood Ali Hafiz Muhammad Tahir Farid Zeinhom M.El-Bahy Department of Physics Faculty of ScienceJazan UniversityJazan45142Saudi Arabia Department of Chemistry Faculty of ScienceKing Khalid UniversityAbha62224Saudi Arabia Department of Physics The Government Sadiq College Women UniversityBahawalpur63100Pakistan Institute of Physics Khwaja Fareed University of Engineering and Information TechnologyRahim Yar Khan64200Pakistan Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Centre of Excellence in Solid State Physics University of the PunjabLahorePakistan Department of Physics Government CollegeTaunsa Sharif32200Pakistan Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr City11884CairoEgypt

Spinel ferrites exhibit exceptional magnetic properties,making them a distinctive class of magnetic *** sol-gel technique was utilized for the synthesis of spinel ferrites with the chemical formula Co_(0.6)Sr_(0.4)Ce_(x)Fe_(2-x)O_(4). Following that,a comprehensive X-ray diffraction analysis unveiled the crystalline cubic structure of the synthesized *** the utilization of the M-H loop approach,the ferromagnetic attributes of ferrites were assessed,and the assimilation of rare earth elements led to substantial enhancements in saturation magnetization,remanence,and *** ferrites with a high concentration of rare earth elements have improved direct current resistivity and activation *** logarithm of a material's resistance increased from 5.29 to 8.12 Ω·cm as cerium is *** a change in the amount of cerium,the activation energy goes up from 0.19 to *** changing the frequency from 5.5 to 9.5 GHz,the dielectric characteristics were *** the frequency goes up,the dielectric constant goes *** ferrites that have been made better in every way can be used in high-frequency applications.

关键词： Activation energy DC electrical resistance Remanence magnetization Cobalt strontium spinel ferrites High frequency application Rare earths

Optimizing calcination of coal by-products for maximizing REE leaching recovery and minimizing Al,Ca,and Fe contamination

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Journal of Rare Earths 2024年第7期42卷 1354-1365,I0006页

作者： Tushar Gupta ahmad Nawab Rick Honaker MP Materials Mountain Pass Mine 67750 Bailey RoadMountain PassCA92366USA Department of Mining Engineering University of KentuckyLexingtonKY40506USA

High-temperature calcination is effective in improving the leaching characteristics of rare earth elements(REEs)from conventional REE-bearing minerals by transforming them into more leachable ***,the recovery of contaminants such as Al,Fe,and Ca also increases *** objective of the study was to maximize the REE extraction while minimizing the concentration of contaminant ions(Al,Ca,and Fe)in the leach *** density fractions of the coarse refuse from the Baker and Fire Clay seam coal refuse were pulverized to a top size of 180μm and used as a feedstock for the *** the samples generated from thermal treatment were leached at 1%(w/v)using 1.2 mol/L sulfuric acid at 75℃ for 2 *** results from a parametric program based on a Box-Behnken design were used for modeling and optimization of three operating parameters associated with the lab-scale calcination *** parameters included temperature(400-800℃),ramp rate(2-10℃/min)and holding time(0-120 min).It was determined that the calcination temperature was the most significant parameter influencing REE *** majority of the heavy rare earth elements(HREEs)were found to be present in an insoluble form in the calcination products and were marginally affected by thermal treatment.A strong correlation between light rare earth elements recovery(LREEs)and Al suggested a possible association with *** optimum operating conditions for high REE recovery with comparatively lower contaminant concentration for 1.6 specific gravity float and 2.2 sink fractions of Baker and Fire Clay seam material were determined to be at 776,800℃ and 407,800℃,calcining temperatures,respectively.A higher optimum temperature of 1.6 float fraction of Baker seam relative to Fire Clay seam material was due to elevated pyrite concentration in Baker seam *** treatment at 400℃ converted pyrite into a soluble intermedium iron oxide,resulting in a high Fe content in the ***

关键词： Calcination Optimization Rare earth elements Coal refuse

Applying the Protective Mn-Co-La_(2)O_(3)Coating on Crofer 22 APU Ferritic Stainless Steel Used as Solid Oxide Fuel Cell Interconnects

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 872-888页

作者： Farhad Mohsenifar Hadi Ebrahimifar ahmad Irannejad Department of Materials Engineering and Metallurgy Faculty of EngineeringShahid Bahonar University of KermanKermanIran Mechanical Engineering Department Faculty of EngineeringHigher Education Complex of Bam76615-314BamIran Department of Materials Engineering Faculty of Mechanical and Materials EngineeringGraduate University of Advanced TechnologyKerman ***Iran

This research studies the effect of Mn-Co-La_(2)O_(3) coating synthesized by the electrodeposition method on the oxidation resistance and electrical conductivity of the Crofer 22 APU stainless steel interconnect plates in solid oxide fuel *** test samples were characterized by a field emission scanning electron microscope(FESEM)equipped with energy dispersive spectroscopy(EDS),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).The oxidation kinetics of the coated and uncoated samples were studied by tracking their weight changes over time at 800°C,showing that the oxidation mechanism for all samples follows the parabolic *** oxidation rate constant(k_(p))values of the coated sample compared with that of the uncoated one indicated a reduction in the oxidation rate of the steel substrate in the presence of the Mn-Co-La_(2)O_(3) *** examination of the cross-section of different samples after the isothermal oxidation for 500 h at 800°C exhibited that applying the composite coating leads to a decrease in the thickness of the chromia layer formed on the steel ***,under these conditions,the area-specific resistance(ASR)of the coated sample(13.11 mΩcm^(2))is significantly lower than that of the uncoated one(41.45 mΩcm^(2)).

关键词： Area specific resistance Oxidation Fuel cell Composite coating