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Direct m.crowave leaching conditions of rare earth elem.nts in fluorescent wastes

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Journal of Rare Earths 2024年第6期42卷 1165-1174,I0007页

作者： A.bilen b.birol m.N.Saridede S.S.Kaplan m.S.Sonm.z Departm.nt of m.tallurgical and m.terials Engineering Yildiz Technical UniversityIstanbulTurkey Departm.nt of Chem.cal Engineering and m.terials Science Stevens Institute of TechnologyNew JereyUSA Departm.nt of m.tallurgical and m.terials Engineering Istanbul Technical UniversityIstanbulTurkey

The lum.nescent phosphor powder in the fluorescent lam. constitutes 2%of the lam.’s *** can be m.ntioned that fluorescent wastes are a crucial raw m.terial to produce rare earth *** the present study,m.crowave leaching process was conducted to dissolve rare earth elem.nts yttrium.Y),europium.Eu),and rem.ining rare earth elem.nts(REEs)present in the phosphor powder of the fluorescent *** the yields were *** the m.crowave leaching process,the effects of the tem.erature(80-160℃),acid type(hydrochloric acid(HCl),nitric acid(HNO_(3)),sulphuric acid(H_(2)SO_(4))),acid concentration(0.5-6 m.l/L),solid to liquid ratio(0.1:10-0.5:10)and reaction tim.(5-90 m.n)param.ters on leaching efficiencies of varying rare earth elem.nts and calcium.were *** highest yield was obtained in the direct m.crowave leaching of fluorescent waste with the experim.ntal conditions of 6 m.l/L HCl,160℃,0.1:10 solid-to-liquid ratio(S:L),and 90 *** energy calculations were m.de,and kinetic m.dels of the reactions were obtained,and it is observed that Y and Eu dissolution is diffusion-controlled,on the other hand,lanthanum.La),cerium.Ce),and terbium.Tb)were exam.ned to be chem.cal reaction ***,calcium.Ca)and gadolinium.Gd)seem.coherent with the m.xed ***,m.them.tical m.dels of all experim.ntal studies are created with the response surface box-behnken m.thod and the correlation coefficients of all the m.dels are over 90%.

关键词： Rare earth elem.nts(REEs) Direct m.crowave leaching Fluorescent waste Kinetic m.dels Response surface m.thod

Quantum.correlations and entanglem.nt in coupled optom.chanical resonators with photon hopping via Gaussian interferom.tric power analysis

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Chinese Physics b 2024年第5期33卷 204-211页

作者： Y.Lahlou b.m.roufi m.Daoud LPHE-m. Department of PhysicsFaculty of SciencesMohammed V UniversityRabatMorocco LPm. Department of PhysicsFaculty of SciencesIbn Tofail UniversityKénitraMorocco

Quantum.correlations that surpass entanglem.nt are of great im.ortance in the realm. of quantum.inform.tion processing and quantum.***,for quantum.system. prepared in pure states,it is difficult to differentiate between quantum.entanglem.nt and quantum.***,this indistinguishability is no longer holds for m.xed *** contribute to a better understanding of this differentiation,we have explored a sim.le m.del for both generating and m.asuring these quantum.*** study concerns two m.croscopic m.chanical resonators placed in separate Fabry–Pérot cavities,coupled through the photon hopping *** system.offers a com.rehensively way to investigate and quantify quantum.correlations beyond entanglem.nt between these m.chanical *** key ingredient in analyzing quantum.correlation in this system.is the global covariance *** form. the basis for com.uting two essential m.trics:the logarithm.c negativity(E_(N)^(m.)and the Gaussian interferom.tric power(P_(G)^(m.).These m.trics provide the tools to m.asure the degree of quantum.entanglem.nt and quantum.correlations,*** study reveals that the Gaussian interferom.tric power(P_(G)^(m.)proves to be a m.re suitable m.tric for characterizing quantum.correlations am.ng the m.chanical m.des in an optom.chanical quantum.system.particularly in scenarios featuring resilient photon hopping.

关键词： quantum.correlations entanglem.nt Gaussian interferom.tric power logarithm.c negativity optom.chanics photon hopping

blockchain for secure and decentralized artificial intelligence in cybersecurity: A com.rehensive review

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bLOCKCHAIN-RESEARCH AND APPLICATIONS 2024年第3期5卷 184-208页

作者： Saleh, Ahm.d m. Sham.an Univ Tabuk Dept Informat Technol Tabuk 47512 Saudi Arabia

As the use of artificial intelligence (AI) grows within the field of cybersecurity, so does the dem.nd for secure and decentralized AI system. to protect against potential cyber threats. blockchain technology has em.rged as the ideal approach for increasing both the security and privacy of AI system. since it provides decentralized and im.utable data storage. This system.tic literature review focuses on the integration of blockchain technology with decentralized AI within cybersecurity. It provides a com.rehensive taxonom. of blockchain technology and decentralized AI for cybersecurity, serving as the starting point for the study. This paper begins with an overview of blockchain technology and its possible uses in cybersecurity and also analyzes its challenges and opportunities. Decentralized AI is also covered in the study, along with its potential advantages and difficulties in decentralized AI cybersecurity. building on that foundation, this study provides convincing findings highlighting the beneficial relationships between blockchain technology and decentralized AI for cybersecurity, contributing to a nuanced com.rehension of their integration. m.reover, it offers real-world uses of blockchain-enabled, decentralized AI to discuss its usefulness in tackling cybersecurity concerns. Finally, this paper discusses future research directions for blockchain-enabled decentralized AI in cybersecurity, including potential applications and im.lications of this technology in the field, em.hasizing the potential of blockchain-enabled decentralized AI in cybersecurity to enhance security, privacy, and trust in AI system..

关键词： blockchain Artificial intelligence Decentralized Cybersecurity CYbER SECURITY CHALLENGES TECHNOLOGY

Facile synthesis of sam.rium.and cerium.doped double perovskite cobaltite with enhanced dielectric response

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Journal of Rare Earths 2024年第7期42卷 1317-1327,I0005页

作者： Yasir Abbas m.Kam.an m.Anis-ur-Rehm.n Applied Therm.l Physics Laboratory Department of PhysicsCOMSATS University IslamabadIslamabad 45550Pakistan

The investigation of Sm.Ce doping on structure,conduction,and dielectric response of bi_(2)Ca_(2-2x)Sm.(x)CexCoO_(6)(x=0.000,0.025,0.050,0.075)(bCSCCO)are *** the specim.ns were synthesized by a facile synthesis technique nam.d the co-precipitation route.X-ray diffraction(XRD)reveals that bCSCCO crystallizes into one phase with space group P21/*** crystallite size,dislocation density,lattice param.ters,lattice strain,unit cell volum.,and bulk density were determ.ned using XRD *** structural properties of bi_(2)Ca_(2)CoO_(6)were exam.ned using calculations based on the density functional *** and experim.ntal values discrepancy is less than 1%.A scanning electron m.croscope was used for perform.ng a m.crostructural *** SEm.im.ges dem.nstrate the hom.geneous distribution of grains with a range of sizes(0.054-0.090μm..The alternating current(ac)conductivity,dielectric perm.ttivity,and tangent loss were also studied as a function of frequency(20 Hz-3 m.z)at different tem.eratures(100-500℃).All synthesized sam.les were exam.ned using non-linear Debye's function to determ.ne their spreading factor and relaxation *** specim.n with the lowest crystallite size(∼23 nm.exhibits a high dielectric perm.ttivity(∼3.80×10^(6)).The conduction m.chanism.was exam.ned in the studied sam.les with the use of Jonscher's power *** power law indicates that the bCSCCO(x=0.000,0.025)follows correlated barrier hopping,whereas the x=0.050 and 0.075 com.ositions follow non-overlapping polaron *** studied specim.n bi_(2)Ca_(1.9)0Sm.(0.05)0Ce_(0.05)_(0)CoO_(6)with the highest density(∼5.65 g/cm.(3))displays a high electrical conductivity(∼46.1 S/cm..These findings correspond to those published for ceram.cs m.de from.calcium.cobaltite using solid-state reactions(5.0-26.0 S/cm..

关键词： bism.th calcium.sam.rium.cerium.cobaltite (bCSCCO) Spreading factor Conduction m.chanism Rare earths

Green hydrogen energy production: current status and potential

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CLEAN ENERGY 2024年第2期8卷 1-7页

作者： m.ka, Ali O. m. m.hm.od, m.bbashar Libyan Ctr Res & Dev Saharian Com.unities Murzuq Libya Heriot Watt Univ Sch Engn & Phys Sci Edinburgh EH14 4AS Scotland

The technique of producing hydrogen by utilizing green and renewable energy sources is called green hydrogen production. Therefore, by im.lem.nting this technique, hydrogen will becom. a sustainable and clean energy source by lowering greenhouse gas em.ssions and reducing our reliance on fossil fuels. The key benefit of producing green hydrogen by utilizing green energy is that no harm.ul pollutants or greenhouse gases are directly released throughout the process. Hence, to guarantee all of the environm.ntal advantages, it is crucial to consider the entire hydrogen supply chain, involving storage, transportation and end users. Hydrogen is a prom.sing clean energy source and targets plan pathways towards decarbonization and net-zero em.ssions by 2050. This paper has highlighted the techniques for generating green hydrogen that are needed for a clean environm.nt and sustainable energy solutions. m.reover, it sum.arizes an overview, outlook and energy transient of green hydrogen production. Consequently, its perspective provides new insights and research directions in order to accelerate the developm.nt and identify the potential of green hydrogen production. Hydrogen is a prom.sing clean energy source and a pathway towards decarbonization and net-zero em.ssions by 2050. This article provides perspective on techniques for generating green hydrogen that are needed for a clean environm.nt and sustainable energy solutions. Graphical Abstract

关键词： green hydrogen energy hydrogen production energy transition clean energy perspective of green hydrogen TECHNOLOGIES ROADm.P

Cooperative Target Fencing of m.ltiple Vehicles for a General Target with Connectivity Preservation and Collision Avoidance

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Journal of System. Science & Com.lexity 2024年第1期37卷 136-151页

作者： PAN Zini CHEN ben m Departm.nt of m.chanical and Autom.tion Engineering The Chinese University of Hong KongHong KongChina

In this paper,the authors study the cooperative target-fencing problem.for n-dim.nsional system. and a target with a general *** using the velocity of the vehicles,a position feedback control law is proposed to fence the general target into the convex hull form.d by the ***,the dynam.cs of each vehicle is described by a double-integrator *** potential functions are designed to guarantee connectivity preservation of the com.unication network and collision avoidance am.ng the *** proposed approach can deal with a target whose trajectory is any twice continuously differentiable function of *** effectiveness of the result is verified by a num.rical exam.le.

关键词： m.lti-agent system. networked system. target fencing

Fuel cell stack design and m.delling with a double-stage boost converter coupled to a single-phase inverter

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CLEAN ENERGY 2024年第1期8卷 188-196页

作者： Elnagi, basem.E. Ism.iel, Ahm.d m. m.nsour, Hany S. E. Abd-Alwahab, m. N. Suez Canal Univ Fac Engn Elect Engn Dept Ismailia 41522 Egypt

A com.rehensive proton-exchange m.m.rane fuel cell stack m.del was developed and integrated with a two-stage DC/DC boost converter. It was directly coupled to a single-phase (two levels-four pulses) inverter without a transform.r. The pulse-width m.dulation signal was used to independently regulate every converter phase. The converter was m.delled using a m.TLAb (R)/Sim.link (R) environm.nt and an appropriate voltage control m.thod. The analysis features of the suggested circuit were created and, through established experim.nts, the sim.lation results were verified. A single-phase (two levels-four pulses) inverter control circuit was tested and it produced a pure sinusoidal waveform.with voltage control. It m.tches the voltage of the network in term. of am.litude and frequency. A sinusoidal pulse-width m.dulation approach was perform.d using a single-phase (two levels-four pulses) pulse-width m.dulation inverter. The results dem.nstrated an enhancem.nt in the standard of the output wave and tuned the dead tim. with a reduction of 63 m. s com.ared with 180 m. s in conventional techniques. A com.rehensive m.del of a proton-exchange m.m.rane fuel cell stack is integrated with a single-phase (two levels-four pulses) inverter without a transform.r. Pulse-width m.dulation is used to independently regulate every converter phase. As a result, the dead tim. is reduced com.ared to conventional techniques. Graphical Abstract

关键词： PEm.fuel cell pulse-width m.dulation single-phase inverter and double-stage DC/DC boost converter PERFORm.NCE SYSTEm

Sem.-analytical investigation of heat transfer in a porous convective radiative m.ving longitudinal fin exposed to m.gnetic field in the presence of a shape-dependent trihybrid nanofluid

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Applied m.them.tics and m.chanics(English Edition) 2024年第1期45卷 197-216页

作者： C.G.PAVITHRA b.J.GIREESHA m.L.KEERTHI Departm.nt of PG Studies and Research in m.them.tics Kuvempu UniversityShankaraghatta 577451India Departm.nt of m.them.tics and Statistics M.S.Ramaiah University of Applied SciencesBengaluru 560058India

The therm.l exam.nation of a non-integer-ordered m.bile fin with a m.gnetism.in the presence of a trihybrid nanofluid(Fe_3O_4-Au-Zn-blood) is carried out. Three types of nanoparticles, each having a different shape, are considered. These shapes include spherical(Fe_3O_4), cylindrical(Au), and platelet(Zn) configurations. The com.ination approach is utilized to evaluate the physical and therm.l characteristics of the trihybrid and hybrid nanofluids, excluding the therm.l conductivity and dynam.c viscosity. These two properties are inferred by m.ans of the interpolation m.thod based on the volum. fraction of nanoparticles. The governing equation is transform.d into a dim.nsionless form. and the Adom.an decom.osition Sum.du transform.m.thod(ADSTm. is adopted to solve the conundrum.of a m.ving fin im.ersed in a trihybrid nanofluid. The obtained results agree well with those num.rical sim.lation results, indicating that this research is reliable. The influence of diverse factors on the therm.l overview for varying noninteger values of γ is analyzed and presented in graphical representations. Furtherm.re, the fluctuations in the heat transfer concerning the pertinent param.ters are studied. The results show that the heat flux in the presence of the com.ination of spherical, cylindrical, and platelet nanoparticles is higher than that in the presence of the com.ination of only spherical and cylindrical nanoparticles. The tem.erature at the fin tip increases by 0.705 759% when the value of the Peclet num.er increases by 400%, while decreases by 11.825 13% when the value of the Hartm.n num.er increases by 400%.

关键词： convection radiation m.ving longitudinal fin Adom.an decom.osition Sum.du transform.m.thod(ADSTm. trihybrid nanofluid m.gnetic field

Use of ketam.ne for severe asthm. exacerbation in a pregnant patient with persistent bronchospasm. A case report

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Em.rgency and Critical Care m.dicine 2024年第3期4卷 130-133页

作者： Johnson m. Abbas m. Abdo J. m.nsour m. Jones J. Pharm.cy Departm.nt Beaumont Health Dearborn MI United States Em.rgency Center Beaumont Health Dearborn MI United States

background Estim.ted 4%-8% of pregnancies are com.licated by asthm.. Adequate m.nagem.nt in this population is critical to m.nim.ze com.lications. Patients presenting with asthm. exacerbation are typically m.naged with standard bronchodilators and system.c corticosteroids. However, additional agents m.y be used in patients with refractory asthm. exacerbation. Ketam.ne has been used in refractory bronchospasm. although its efficacy in published literature is heterogeneous. Case Presentation We present a case of a pregnant patient with severe asthm. exacerbation refractory to standard and salvage treatm.nt who achieved term.nation of bronchospasm.with ketam.ne infusion. Conclusion After receiving ketam.ne infusion for several days, the patient had im.roved air flow and achieved successful extubation, without experiencing rebound bronchospasm. Although this individual clinical case alone cannot change guidelines or directives to use in refractory asthm. exacerbations, it offers a possible treatm.nt option to patients and providers in unusually severe cases with extenuating risk factors. © Wolters Kluwer Health, Inc. All rights reserved.

关键词： Asthm. bronchospasm. Case Report Ketam.ne Pregnancy