Inertial confinement fusion(ICF)requires a constant search for the most effective materials to improve the efficiency of compression of the capsule and of laser-to-target energy transfer.Foams could provide a solution...Inertial confinement fusion(ICF)requires a constant search for the most effective materials to improve the efficiency of compression of the capsule and of laser-to-target energy transfer.Foams could provide a solution,but they require further experimental and theoretical investigation.The new 3D-printing technologies,such as two-photon polymerization,are opening a new era in the production of foams,allowing fine control of material morphology.Very few detailed studies of the interaction of foams with high-power lasers in regimes relevant for ICF have been described in the literature to date,and more investigation is needed.In this work,we present the results of an experimental campaign performed at the ABC laser facility at ENEA Centro Ricerche Frascati in which 3D-printed microstructured materials were irradiated at high power.3D simulations of the laser-target interaction performed with the FLASH code reveal that the laser is scattered by plasma density gradients and channeled into the structure when the center of the focal spot is on the through hole.The time required for the laser to completely ablate the structure given by the simulations is in good agreement with the experimental measurement.Measurements of the reflected and transmitted laser light indicate that scattering occurred during the irradiation,in accordance with the simulations.Two-plasmon decay has also been found to be active during irradiation.展开更多
We perform the manifestly covariant quantization of f(R)gravity in the de Donder gauge condition(or harmonic gauge condition)for general coordinate invariance.We explicitly calculate various equal-time commutation rel...We perform the manifestly covariant quantization of f(R)gravity in the de Donder gauge condition(or harmonic gauge condition)for general coordinate invariance.We explicitly calculate various equal-time commutation relations(ETCRs),in particular the ETCR between the metric and its time derivative,and show that it has a nonvanishing and nontrivial expression,whose situation should be contrasted to the previous result in higher-derivative or quadratic gravity where the ETCR was found to be identically vanishing.We also clarify global symmetries,the physical content of f(R)gravity,and clearly show that this theory is manifestly unitary and has a massive scalar and massless graviton as physical modes.展开更多
Skin injury repair is a complicated process that involves wound healing.Effective wound dressings play a crucial role in enhancing this process by providing multiple functions,such as wettability,antibacterial activit...Skin injury repair is a complicated process that involves wound healing.Effective wound dressings play a crucial role in enhancing this process by providing multiple functions,such as wettability,antibacterial activity,and drug release.In this study,Calophyllum inophyllum oil(CIO)is incorporated into polyethylene oxide-polyvinyl acetate(PEO-PVAc)nanofibers using an electrospinning technique.The successful incorporation is verified by Fourier-transform infrared spectroscopy,while the morphology is observed by scanning electron microscopy.The fabricated nanofibers are beadless and have fiber diameter distributions of 333–472 nm.The addition of CIO significantly improves the wettability of the nanofibers,as indicated by a decrease in water contact angle,which is crucial for accelerating the healing process.Additionally,the CIO exhibits potent antibacterial activity against both Gram-positive(Escherichia coli)and Gram-negative(Staphylococcus aureus)bacteria,with expanding inhibition zones as the CIO concentration is increased.These findings highlight the great potential of PEO-PVAc/CIO nanofibers for advanced wound healing applications.展开更多
We compute electronic and thermoelectric properties and density of states of disordered kagome lattice doped with impurity atoms in the context of tight binding model Hamiltonian due to spin-orbit coupling.The effect ...We compute electronic and thermoelectric properties and density of states of disordered kagome lattice doped with impurity atoms in the context of tight binding model Hamiltonian due to spin-orbit coupling.The effect of scattering by dilute charged impurities is discussed in terms of the self-consistent Born approximation.Green's function approach has been implemented to find the behavior of density of states and transport properties of kagome lattice.Specially,temperature dependences of electrical and thermal conductivities of kagome structure in the presence of impurity atoms have been analyzed.Also the effects of impurity concentration and scattering potential strength on behaviors of thermoelectric properties of kagome structure have been studied.Specially,the behaviors of Seebeck coefficient,power factor function,figure of merit and Lorenz number of the system have been analyzed in the presence of both impurity atoms and spin-orbit coupling effects.Our results show that impurity concentration leads to reduction of transport properties and thermoelectric factors of the disordered kagome lattice.展开更多
Detecting geomagnetic anomalies preceding earthquakes is a challenging yet promising area of research that has gained increasing attention in recent years.This study introduces a novel reconstruction-based modeling ap...Detecting geomagnetic anomalies preceding earthquakes is a challenging yet promising area of research that has gained increasing attention in recent years.This study introduces a novel reconstruction-based modeling approach enhanced by negative learning,employing a Bidirectional Long Short-Term Memory(BiLSTM)network explicitly trained to accurately reconstruct non-seismic geomagnetic signals while intentionally amplifying reconstruction errors for seismic signals.By penalizing the model for accurately reconstructing seismic anomalies,the negative learning approach effectively magnifies the differences between normal and anomalous data.This strategic differentiation enhances the sensitivity of the BiLSTM network,enabling improved detection of subtle geomagnetic anomalies that may serve as earthquake precursors.Experimental validation clearly demonstrated statistically significant higher reconstruction errors for seismic signals compared to non-seismic signals,confirmed through the Mann-Whitney U test with a p-value of 0.0035 for Root Mean Square Error(RMSE).These results provide compelling evidence of the enhanced anomaly detection capability achieved through negative learning.Unlike traditional classification-based methods,negative learning explicitly encourages sensitivity to subtle precursor signals embedded within complex geomagnetic data,establishing a robust basis for further development of reliable earthquake prediction methods.展开更多
A compilation of databases from Cameroon and neighbouring countries,including seismicity,stress tensor distribution,gravity,magnetic,topography,lithosphere structure and geological data,is used to define its seismotec...A compilation of databases from Cameroon and neighbouring countries,including seismicity,stress tensor distribution,gravity,magnetic,topography,lithosphere structure and geological data,is used to define its seismotectonic zonation.Based on the quality and quantity of available data,a seismotectonic map was drawn up through the characterization of subunits of concentrations of earthquake foci and,large neotectonic and structural domains.To prepare this map,a homogeneous earthquake catalogue was compiled from the literature and international data centers dated from 1852 up to 2023.Another point of study was to establish links between seismicity and deformation zones.Many faults and/or structures were identified as possibly active,although some of them are not always associated with seismicity.A seismotectonic model for Cameroon was then built from a classification of faults,neotectonic and seismogenic regions.This structured and highly data-driven approach has been developed specifically for the definition of source zones where seismicity is not well known.The results of the seismotectonic analysis allowed characterizing seventeen seismotectonic source zones in Cameroon.Five source zones are defined in the Mount Cameroon region which is the greatest seismicity activity in the study area.The crustal thickness map of Cameroon revealed a thinned transitional zone interspersed between the thickened Congo Shield and thin Pan-African belt favourable for the development of megastructures such as Central Cameroon shear zone and Kribi-Campo shear zone.This region represents the second highest seismicity zone and contains five source zones.展开更多
Lithium-ion batteries(LIBs),while dominant in energy storage due to high energy density and cycling stability,suffer from severe capacity decay,rate capability degradation,and lithium dendrite formation under low-temp...Lithium-ion batteries(LIBs),while dominant in energy storage due to high energy density and cycling stability,suffer from severe capacity decay,rate capability degradation,and lithium dendrite formation under low-temperature(LT)operation.Therefore,a more comprehensive and systematic understanding of LIB behavior at LT is urgently required.This review article comprehensively reviews recent advancements in electrolyte engineering strategies aimed at improving the low-temperature operational capabilities of LIBs.The study methodically examines critical performance-limiting mechanisms through fundamental analysis of four primary challenges:insufficient ionic conductivity under cryogenic conditions,kinetically hindered charge transfer processes,Li+transport limitations across the solidelectrolyte interphase(SEI),and uncontrolled lithium dendrite growth.The work elaborates on innovative optimization approaches encompassing lithium salt molecular design with tailored dissociation characteristics,solvent matrix optimization through dielectric constant and viscosity regulation,interfacial engineering additives for constructing low-impedance SEI layers,and gel-polymer composite electrolyte systems.Notably,particular emphasis is placed on emerging machine learning-guided electrolyte formulation strategies that enable high-throughput virtual screening of constituent combinations and prediction of structure-property relationships.These artificial intelligence-assisted rational design frameworks demonstrate significant potential for accelerating the development of next-generation LT electrolytes by establishing quantitative composition-performance correlations through advanced data-driven methodologies.展开更多
Hydrogen peroxide(H_(2)O_(2)) has been recognized as a green and nonpolluting multifunctional oxidant with extensive applications in environmental protection,metal etching,textile printing and dyeing,chemical synthesi...Hydrogen peroxide(H_(2)O_(2)) has been recognized as a green and nonpolluting multifunctional oxidant with extensive applications in environmental protection,metal etching,textile printing and dyeing,chemical synthesis and food processing.However,over 90 % of industrial H_(2)O_(2) is currently produced through the multi-step anthraquinone oxidation process,which suffers from a process with some drawbacks such as complex,high-energy consumption,and toxic byproducts emissions.Compared to the traditional anthraquinone method,artificial photosynthesis of H_(2)O_(2) using semiconductor photocatalysts has emerged as a sustainable alternative due to its use of water and O_(2) as the clean reactants and sole energy as the driving force.In recent years,metal-free photocatalysts mainly including covalent organic frameworks(COFs),covalent triazine frameworks(CTFs) and carbon nitrile(g-C_(3)N_(4)) have garnered significant interest due to their superior thermal and chemical stability,diverse synthesis methods,tunable functionality,light weight nature and non-toxicity.These materials also exhibit adjustable band structure and unique photoelectric properties.Sustainable efforts have been made to advance metal-free photocatalysts for artificial photosynthesis of H_(2)O_(2),however,a comprehensive summary of current research status on metalfree-based photocatalytic overall H_(2)O_(2) production remain scarce.This review outlines recent process in overall H_(2)O_(2) photosynthesis based on metal-free photocatalysts.First,we introduced the fundamental concepts of photocatalytic overall H_(2)O_(2) production.Then,we analyze representative studies on photocatalytic overall H_(2)O_(2) synthesis using metal-free materials.Finally,we discuss the challenges and future perspectives in this field to guide the design and synthesis of metal-free systems for H_(2)O_(2) generation.展开更多
Cu_(x)Ta_(2-x)O_(5) compositions were investigated for advanced thermoelectric and optical applications,using both simulations and experimental approaches.Density functional theory calculations were performed before t...Cu_(x)Ta_(2-x)O_(5) compositions were investigated for advanced thermoelectric and optical applications,using both simulations and experimental approaches.Density functional theory calculations were performed before the experimental observations to predict the trends of various parameters.Crystal structure analysis confirmed the presence of the orthorhombic Ta_(2)O_(5) phase in all the compositions.The composition and morphology demonstrated impurity-free contents with uniform and crack-free surfaces.Thermoelectric analysis depicted a decrease in Seebeck coefficient from 3.66µV·K^(-1)to 1.91µV·K^(-1)and an increase in the value of specific heat from 0.73 J·K^(-1)·kg^(-1)to 11.6 J·K^(-1)·kg^(-1)upon Cu incorporation in structure.The bandgap was found to reduce from 2.61 to 1.38 e V with Cu-induced electronic states.The real epsilon and static refractive index increased from 3.75 to 4.57 and from 1.93 to 2.11,respectively,with increment in Cu content.The enhanced parameters,focusing on the thermoelectric and optical responses,make these compositions potential candidates for advanced optoelectronic applications.展开更多
This research presents a detailed ab initio density functional theory(DFT)analysis on magnetic,thermoelectric,and optoelectronic properties of CaPr_(2)(S/Se)_(4) executed by Wien2k and Boltztrap2 packages for spintron...This research presents a detailed ab initio density functional theory(DFT)analysis on magnetic,thermoelectric,and optoelectronic properties of CaPr_(2)(S/Se)_(4) executed by Wien2k and Boltztrap2 packages for spintronic energy applications.The density of states,optimization energy,and negative formation energy all support the stability of the ferromagnetic state.The spin polarization density and Curie temperature(310 and 289 K)are also reported.In addition,the double exchange model,hybridization,density of states,band structures,exchange constants,exchange energies,and crystal field energies are addressed to ensure ferromagnetism by the spin of electrons.The magnetic moment of Pr shifts to Ca and S/Se sites,revealing that ferromagnetism is due to electron spin,not clustering of Pr magnetic ions.Thermoelectrics were evaluated by electrical conductivity(σ),thermal conductivity(k_(e)),Seebeck coefficient(S),power factor(S^(2)),and figures of merit(ZT).The room tempe rature values of S(0.169,0.183 mV/K)and ZT(0.76,0.90)increase their thermoelectric performance.Furthermore,dielectric function,refractive index,absorption coefficientα(ω),reflectivity R(ω),and other parameters are demonstrated in detail.Therefore,researchers can develop materials with the potential for spintronic and energy harvesting.展开更多
Demonstrating significant achievements in efficiency,perovskite solar cells(PSCs)have acquired unique positions in photovoltaics,offering alternatives to conventional commercial silicon solar cells.While there has bee...Demonstrating significant achievements in efficiency,perovskite solar cells(PSCs)have acquired unique positions in photovoltaics,offering alternatives to conventional commercial silicon solar cells.While there has been significant progress in enhancing photovoltaic performance,obvious stability problems remain a primary challenge that continues to hinder the commercial viability of PSCs.This present review first comprehensively discusses the main challenges to the commercialization of PSCs,including stability problems,ion migration,toxicity,and complexities in large-scale fabrication.It then effectively presents universal strategies to overcome the mentioned problems.Moreover,this review article examines various printing techniques that can be used to improve PSCs,emphasizing their benefits like low-cost components and procedures.Several printing processes are covered in the discussion,such as slot-die coating,spray coating,inkjet printing,doctor-blade coating,roll-to-roll printing,and screen printing.The potential uses of PSCs for the implementation of greenhouses,building-integrated photovoltaic systems,and indoor light energy harvesting.These uses highlight the adaptability of PSCs and demonstrate their ability to transform energy production technologies.Additionally,this review highlights the special qualities of perovskite materials that present chances to surpass silicon solar cells'efficiency restrictions and get close to the Shockley-Queisser limit.In conclusion,the current review provides a brief overview of recent developments,existing challenges,and opportunities of PSCs.It provides a thorough understanding of the merits of highly efficient PSCs fabricated by adopting printing methods to tackle stability problems along with facile fabrication of PSCs using simplified and cost-effective strategies.展开更多
In this study,COMSOL v5.2 Multiphysics software was utilized to perform coupled neutronics and thermal–hydraulics simulations of a molten salt fast reactor,and the SCALE v6.1 code package was utilized to generate the...In this study,COMSOL v5.2 Multiphysics software was utilized to perform coupled neutronics and thermal–hydraulics simulations of a molten salt fast reactor,and the SCALE v6.1 code package was utilized to generate the homogenized cross-section data library.The library’s 238 cross-section groups were categorized into nine groups for the simulations in this study.The results of the COMSOL model under no fuel flow conditions were verified using the SCALE v6.1 code results,and the results of the neutronics and thermal–hydraulics simulations were compared to the results of previously published studies.The results indicated that the COMSOL model that includes the cross-section library generated by the SCALE v6.1 code package is suitable for the steady-state analysis and design assessment of molten salt fast reactors.Subsequently,this model was utilized to investigate the neutronics and thermal–hydraulics behaviors of the reactor.Multiple designs were simulated and analyzed in this model,and the results indicated that even if the wall of the core is curved,hot spots occur in the upper and lower portions of the core’s center near the reflectors.A new design was proposed that utilizes a flow rate distribution system,and the simulation results of this design showed that the maximum temperature in the core was approximately 1032 K and no hot spots occurred.展开更多
In this paper,a new approach is devoted to find novel analytical and approximate solutions to the damped quadratic nonlinear Helmholtz equation(HE)in terms of the Weiersrtrass elliptic function.The exact solution for ...In this paper,a new approach is devoted to find novel analytical and approximate solutions to the damped quadratic nonlinear Helmholtz equation(HE)in terms of the Weiersrtrass elliptic function.The exact solution for undamped HE(integrable case)and approximate/semi-analytical solution to the damped HE(non-integrable case)are given for any arbitrary initial conditions.As a special case,the necessary and sufficient condition for the integrability of the damped HE using an elementary approach is reported.In general,a new ansatz is suggested to find a semi-analytical solution to the non-integrable case in the form of Weierstrass elliptic function.In addition,the relation between the Weierstrass and Jacobian elliptic functions solutions to the integrable case will be derived in details.Also,we will make a comparison between the semi-analytical solution and the approximate numerical solutions via using Runge-Kutta fourth-order method,finite difference method,and homotopy perturbation method for the first-two approximations.Furthermore,the maximum distance errors between the approximate/semi-analytical solution and the approximate numerical solutions will be estimated.As real applications,the obtained solutions will be devoted to describe the characteristics behavior of the oscillations in RLC series circuits and in various plasma models such as electronegative complex plasma model.展开更多
The present paper is basically written as a non-apologetic strong defence of the thesis that computation is part and parcel of a physical theory and by no means a mere numerical evaluation of the prediction of a theor...The present paper is basically written as a non-apologetic strong defence of the thesis that computation is part and parcel of a physical theory and by no means a mere numerical evaluation of the prediction of a theory which comes towards the end. Various general considerations as well as specific examples are given to illustrate and support our arguments. These examples range from the practical aspect to almost esoteric considerations but at the end, everything converges towards a unity of theory and computation presented in the form of modern fractal logic and transfinite quantum field theory in a Cantorian spacetime. It is true that all our examples are taken from physics but our discussion is applicable in equal measure to a much wider aspect of life.展开更多
The present note is basically an announcement of a theoretical and experimental resolution of one of the most basic fundamental problems of physics, namely the very existence and reality of the Aether [1-11]. This is ...The present note is basically an announcement of a theoretical and experimental resolution of one of the most basic fundamental problems of physics, namely the very existence and reality of the Aether [1-11]. This is not only basic philosophy of science or insightful results in theoretical physics and cosmology [1-24] but more than that because it may lead to actually realizing the futuristic dream of free energy [25-28]. Our mathematical and indirect experimental verdict is that the Aether exists and it can be equated to the empty set of pure mathematics [3, 12-16]. More precisely the Aether may be understood for all mathematical and physical purposes as being identical to the empty set [8-14] underlying the Penrose fractal tessellation universe [17] which obeys the A. Connes’ corresponding dimensional function of his noncommutative geometry [18-21].展开更多
At its most basic level physics starts with space-time topology and geometry. On the other hand topology’s and geometry’s simplest and most basic elements are random Cantor sets. It follows then that nonlinear dynam...At its most basic level physics starts with space-time topology and geometry. On the other hand topology’s and geometry’s simplest and most basic elements are random Cantor sets. It follows then that nonlinear dynamics i.e. deterministic chaos and fractal geometry is the best mathematical theory to apply to the problems of high energy particle physics and cosmology. In the present work we give a short survey of some recent achievements of applying nonlinear dynamics to notoriously difficult subjects such as quantum entanglement as well as the origin and true nature of dark energy, negative absolute temperature and the fractal meaning of the constancy of the speed of light.展开更多
A straightforward simple proof is given that dark energy is the natural conse-quence of a quantum disentanglement physical process. Thus while the ordinary energy density of the cosmos is equal to half that of Hardy’...A straightforward simple proof is given that dark energy is the natural conse-quence of a quantum disentanglement physical process. Thus while the ordinary energy density of the cosmos is equal to half that of Hardy’s quantum probability of Entanglement i.e. where , the density of cosmic dark energy is consequently one minus divided by two i.e. . This result is in full agreement with all the numerous previous theoretical predictions as well as being in remarkable agreement with the overwhelming majority of cosmic accurate measurements and observations.展开更多
By religiously adhering to physics in spacetime and taking the final verdict of N.D. Mermin’s Ithaca interpretation of quantum mechanics seriously, Hardy’s paradox is completely resolved. It is then concluded that l...By religiously adhering to physics in spacetime and taking the final verdict of N.D. Mermin’s Ithaca interpretation of quantum mechanics seriously, Hardy’s paradox is completely resolved. It is then concluded that logical and mathematically consistent physical theories must be put in spacetime related formalism such as noncommutative geometry and E-infinity theory to avoid quantum paradoxes. At a minimum, we should employ the philosophy behind consistent quantum interpretation such as that of the famous Ithaca interpretation of D. Mermin.展开更多
Schrfdinger＇s equation is one the equations that mark the beginnings of the systematic quantum physics. It was shown that it follows from the Dirac＇s equation and the relationship with classical physics, i.e. with c...Schrfdinger＇s equation is one the equations that mark the beginnings of the systematic quantum physics. It was shown that it follows from the Dirac＇s equation and the relationship with classical physics, i.e. with classical field theory was established. The subject of this work is the relationship between classical relativistic physics and the quantum physics. Investigation carded out in this work, shows that the free electromagnetic field, spinor Dirac＇s field without mass, spinor Dirac＇s field with mass, and some other fields are described by the same vibrational formulation. The conditions that a field be described by Maxwell＇s equations of motion are given in this work, and some solutions of these conditions are also given. Non-relativistic approximation of the equations of the non-quantified field are the Schrōdinger＇s equations. Dirac＇s equation as a special case, contains Maxwell＇s equations and the Schrōdinger＇s equation.展开更多
基金framework of the EUROfusion Consortium,funded by the European Union via the Euratom Research and Training Programme(Grant Agreement No.101052200—EUROfusion)The CRESCO-ENEAGRID High Performance Computing infrastructure is funded by ENEA+3 种基金the Italian National Agency for New Technologies,Energy and Sustainable Economic Developmentby Italian and European research programmesthe framework of the“Universities’Excellence Initiative”programme by the Ministry of Education,Science and Sports of the Republic of Lithuania under an agreement with the Research Council of Lithuania(Project No.S-A-UEI-23-6)support was received through EU LASERLAB-EUROPE JRAextension(Grant Agreement No.871124,Horizon 2020 Research and Innovation Programme).
文摘Inertial confinement fusion(ICF)requires a constant search for the most effective materials to improve the efficiency of compression of the capsule and of laser-to-target energy transfer.Foams could provide a solution,but they require further experimental and theoretical investigation.The new 3D-printing technologies,such as two-photon polymerization,are opening a new era in the production of foams,allowing fine control of material morphology.Very few detailed studies of the interaction of foams with high-power lasers in regimes relevant for ICF have been described in the literature to date,and more investigation is needed.In this work,we present the results of an experimental campaign performed at the ABC laser facility at ENEA Centro Ricerche Frascati in which 3D-printed microstructured materials were irradiated at high power.3D simulations of the laser-target interaction performed with the FLASH code reveal that the laser is scattered by plasma density gradients and channeled into the structure when the center of the focal spot is on the through hole.The time required for the laser to completely ablate the structure given by the simulations is in good agreement with the experimental measurement.Measurements of the reflected and transmitted laser light indicate that scattering occurred during the irradiation,in accordance with the simulations.Two-plasmon decay has also been found to be active during irradiation.
文摘We perform the manifestly covariant quantization of f(R)gravity in the de Donder gauge condition(or harmonic gauge condition)for general coordinate invariance.We explicitly calculate various equal-time commutation relations(ETCRs),in particular the ETCR between the metric and its time derivative,and show that it has a nonvanishing and nontrivial expression,whose situation should be contrasted to the previous result in higher-derivative or quadratic gravity where the ETCR was found to be identically vanishing.We also clarify global symmetries,the physical content of f(R)gravity,and clearly show that this theory is manifestly unitary and has a massive scalar and massless graviton as physical modes.
基金funded by Rekognisi Tugas Akhir(RTA)program(Contract No.5286/UN1.P1/PT.01.03/2024)supported by Universitas Gadjah Mada,Indonesia.
文摘Skin injury repair is a complicated process that involves wound healing.Effective wound dressings play a crucial role in enhancing this process by providing multiple functions,such as wettability,antibacterial activity,and drug release.In this study,Calophyllum inophyllum oil(CIO)is incorporated into polyethylene oxide-polyvinyl acetate(PEO-PVAc)nanofibers using an electrospinning technique.The successful incorporation is verified by Fourier-transform infrared spectroscopy,while the morphology is observed by scanning electron microscopy.The fabricated nanofibers are beadless and have fiber diameter distributions of 333–472 nm.The addition of CIO significantly improves the wettability of the nanofibers,as indicated by a decrease in water contact angle,which is crucial for accelerating the healing process.Additionally,the CIO exhibits potent antibacterial activity against both Gram-positive(Escherichia coli)and Gram-negative(Staphylococcus aureus)bacteria,with expanding inhibition zones as the CIO concentration is increased.These findings highlight the great potential of PEO-PVAc/CIO nanofibers for advanced wound healing applications.
文摘We compute electronic and thermoelectric properties and density of states of disordered kagome lattice doped with impurity atoms in the context of tight binding model Hamiltonian due to spin-orbit coupling.The effect of scattering by dilute charged impurities is discussed in terms of the self-consistent Born approximation.Green's function approach has been implemented to find the behavior of density of states and transport properties of kagome lattice.Specially,temperature dependences of electrical and thermal conductivities of kagome structure in the presence of impurity atoms have been analyzed.Also the effects of impurity concentration and scattering potential strength on behaviors of thermoelectric properties of kagome structure have been studied.Specially,the behaviors of Seebeck coefficient,power factor function,figure of merit and Lorenz number of the system have been analyzed in the presence of both impurity atoms and spin-orbit coupling effects.Our results show that impurity concentration leads to reduction of transport properties and thermoelectric factors of the disordered kagome lattice.
基金funded by the Ministry of Higher Education through Universiti Putra Malaysia(UPM)under Grant FRGS/1/2023/STG07/UPM/02/4.
文摘Detecting geomagnetic anomalies preceding earthquakes is a challenging yet promising area of research that has gained increasing attention in recent years.This study introduces a novel reconstruction-based modeling approach enhanced by negative learning,employing a Bidirectional Long Short-Term Memory(BiLSTM)network explicitly trained to accurately reconstruct non-seismic geomagnetic signals while intentionally amplifying reconstruction errors for seismic signals.By penalizing the model for accurately reconstructing seismic anomalies,the negative learning approach effectively magnifies the differences between normal and anomalous data.This strategic differentiation enhances the sensitivity of the BiLSTM network,enabling improved detection of subtle geomagnetic anomalies that may serve as earthquake precursors.Experimental validation clearly demonstrated statistically significant higher reconstruction errors for seismic signals compared to non-seismic signals,confirmed through the Mann-Whitney U test with a p-value of 0.0035 for Root Mean Square Error(RMSE).These results provide compelling evidence of the enhanced anomaly detection capability achieved through negative learning.Unlike traditional classification-based methods,negative learning explicitly encourages sensitivity to subtle precursor signals embedded within complex geomagnetic data,establishing a robust basis for further development of reliable earthquake prediction methods.
文摘A compilation of databases from Cameroon and neighbouring countries,including seismicity,stress tensor distribution,gravity,magnetic,topography,lithosphere structure and geological data,is used to define its seismotectonic zonation.Based on the quality and quantity of available data,a seismotectonic map was drawn up through the characterization of subunits of concentrations of earthquake foci and,large neotectonic and structural domains.To prepare this map,a homogeneous earthquake catalogue was compiled from the literature and international data centers dated from 1852 up to 2023.Another point of study was to establish links between seismicity and deformation zones.Many faults and/or structures were identified as possibly active,although some of them are not always associated with seismicity.A seismotectonic model for Cameroon was then built from a classification of faults,neotectonic and seismogenic regions.This structured and highly data-driven approach has been developed specifically for the definition of source zones where seismicity is not well known.The results of the seismotectonic analysis allowed characterizing seventeen seismotectonic source zones in Cameroon.Five source zones are defined in the Mount Cameroon region which is the greatest seismicity activity in the study area.The crustal thickness map of Cameroon revealed a thinned transitional zone interspersed between the thickened Congo Shield and thin Pan-African belt favourable for the development of megastructures such as Central Cameroon shear zone and Kribi-Campo shear zone.This region represents the second highest seismicity zone and contains five source zones.
基金the financial support from the Key Project of Shaanxi Provincial Natural Science Foundation-Key Project of Laboratory(2025SYS-SYSZD-117)the Natural Science Basic Research Program of Shaanxi(2025JCYBQN-125)+8 种基金Young Talent Fund of Xi'an Association for Science and Technology(0959202513002)the Key Industrial Chain Technology Research Program of Xi'an(24ZDCYJSGG0048)the Key Research and Development Program of Xianyang(L2023-ZDYF-SF-077)Postdoctoral Fellowship Program of CPSF(GZC20241442)Shaanxi Postdoctoral Science Foundation(2024BSHSDZZ070)Research Funds for the Interdisciplinary Projects,CHU(300104240913)the Fundamental Research Funds for the Central Universities,CHU(300102385739,300102384201,300102384103)the Scientific Innovation Practice Project of Postgraduate of Chang'an University(300103725063)the financial support from the Australian Research Council。
文摘Lithium-ion batteries(LIBs),while dominant in energy storage due to high energy density and cycling stability,suffer from severe capacity decay,rate capability degradation,and lithium dendrite formation under low-temperature(LT)operation.Therefore,a more comprehensive and systematic understanding of LIB behavior at LT is urgently required.This review article comprehensively reviews recent advancements in electrolyte engineering strategies aimed at improving the low-temperature operational capabilities of LIBs.The study methodically examines critical performance-limiting mechanisms through fundamental analysis of four primary challenges:insufficient ionic conductivity under cryogenic conditions,kinetically hindered charge transfer processes,Li+transport limitations across the solidelectrolyte interphase(SEI),and uncontrolled lithium dendrite growth.The work elaborates on innovative optimization approaches encompassing lithium salt molecular design with tailored dissociation characteristics,solvent matrix optimization through dielectric constant and viscosity regulation,interfacial engineering additives for constructing low-impedance SEI layers,and gel-polymer composite electrolyte systems.Notably,particular emphasis is placed on emerging machine learning-guided electrolyte formulation strategies that enable high-throughput virtual screening of constituent combinations and prediction of structure-property relationships.These artificial intelligence-assisted rational design frameworks demonstrate significant potential for accelerating the development of next-generation LT electrolytes by establishing quantitative composition-performance correlations through advanced data-driven methodologies.
基金supported by the National Natural Science Foundation of China (No.22409038,52473221)Zhejiang Province Postdoctoral Science Foundation (No.ZJ2024021)+2 种基金Hubei Provincial Natural Science Foundation of China (Nos.2024DJC032,2025AFB889)Key Project of Science and Technology Research of Hubei Provincial Department of Education (Nos.D20232701,D20232702)the research grant funded by the Research,Development,and Innovation Authority (RDIA)-Kingdom of Saudi Arabia (No.12615-iu-2023-IU-R-2-1-EI-)。
文摘Hydrogen peroxide(H_(2)O_(2)) has been recognized as a green and nonpolluting multifunctional oxidant with extensive applications in environmental protection,metal etching,textile printing and dyeing,chemical synthesis and food processing.However,over 90 % of industrial H_(2)O_(2) is currently produced through the multi-step anthraquinone oxidation process,which suffers from a process with some drawbacks such as complex,high-energy consumption,and toxic byproducts emissions.Compared to the traditional anthraquinone method,artificial photosynthesis of H_(2)O_(2) using semiconductor photocatalysts has emerged as a sustainable alternative due to its use of water and O_(2) as the clean reactants and sole energy as the driving force.In recent years,metal-free photocatalysts mainly including covalent organic frameworks(COFs),covalent triazine frameworks(CTFs) and carbon nitrile(g-C_(3)N_(4)) have garnered significant interest due to their superior thermal and chemical stability,diverse synthesis methods,tunable functionality,light weight nature and non-toxicity.These materials also exhibit adjustable band structure and unique photoelectric properties.Sustainable efforts have been made to advance metal-free photocatalysts for artificial photosynthesis of H_(2)O_(2),however,a comprehensive summary of current research status on metalfree-based photocatalytic overall H_(2)O_(2) production remain scarce.This review outlines recent process in overall H_(2)O_(2) photosynthesis based on metal-free photocatalysts.First,we introduced the fundamental concepts of photocatalytic overall H_(2)O_(2) production.Then,we analyze representative studies on photocatalytic overall H_(2)O_(2) synthesis using metal-free materials.Finally,we discuss the challenges and future perspectives in this field to guide the design and synthesis of metal-free systems for H_(2)O_(2) generation.
基金the Deanship of Research and Graduate Studies at King Khalid University,Saudi Arabia,for funding this study through the Large Groups Project(Grant No.RGP2/2/47)the Deanship of Scientific Research at Northern Border University,Arar,KSA for funding this research work through project number NBU-FFR-2025-1902-02。
文摘Cu_(x)Ta_(2-x)O_(5) compositions were investigated for advanced thermoelectric and optical applications,using both simulations and experimental approaches.Density functional theory calculations were performed before the experimental observations to predict the trends of various parameters.Crystal structure analysis confirmed the presence of the orthorhombic Ta_(2)O_(5) phase in all the compositions.The composition and morphology demonstrated impurity-free contents with uniform and crack-free surfaces.Thermoelectric analysis depicted a decrease in Seebeck coefficient from 3.66µV·K^(-1)to 1.91µV·K^(-1)and an increase in the value of specific heat from 0.73 J·K^(-1)·kg^(-1)to 11.6 J·K^(-1)·kg^(-1)upon Cu incorporation in structure.The bandgap was found to reduce from 2.61 to 1.38 e V with Cu-induced electronic states.The real epsilon and static refractive index increased from 3.75 to 4.57 and from 1.93 to 2.11,respectively,with increment in Cu content.The enhanced parameters,focusing on the thermoelectric and optical responses,make these compositions potential candidates for advanced optoelectronic applications.
文摘This research presents a detailed ab initio density functional theory(DFT)analysis on magnetic,thermoelectric,and optoelectronic properties of CaPr_(2)(S/Se)_(4) executed by Wien2k and Boltztrap2 packages for spintronic energy applications.The density of states,optimization energy,and negative formation energy all support the stability of the ferromagnetic state.The spin polarization density and Curie temperature(310 and 289 K)are also reported.In addition,the double exchange model,hybridization,density of states,band structures,exchange constants,exchange energies,and crystal field energies are addressed to ensure ferromagnetism by the spin of electrons.The magnetic moment of Pr shifts to Ca and S/Se sites,revealing that ferromagnetism is due to electron spin,not clustering of Pr magnetic ions.Thermoelectrics were evaluated by electrical conductivity(σ),thermal conductivity(k_(e)),Seebeck coefficient(S),power factor(S^(2)),and figures of merit(ZT).The room tempe rature values of S(0.169,0.183 mV/K)and ZT(0.76,0.90)increase their thermoelectric performance.Furthermore,dielectric function,refractive index,absorption coefficientα(ω),reflectivity R(ω),and other parameters are demonstrated in detail.Therefore,researchers can develop materials with the potential for spintronic and energy harvesting.
基金Deanship of Research and Graduate Studies at King Khalid University for funding this work through Large Research Project under grant number(R.G.P.2/472/46)Anhui Provoncial Natural Science Foundation(NO.2308085MF211).
文摘Demonstrating significant achievements in efficiency,perovskite solar cells(PSCs)have acquired unique positions in photovoltaics,offering alternatives to conventional commercial silicon solar cells.While there has been significant progress in enhancing photovoltaic performance,obvious stability problems remain a primary challenge that continues to hinder the commercial viability of PSCs.This present review first comprehensively discusses the main challenges to the commercialization of PSCs,including stability problems,ion migration,toxicity,and complexities in large-scale fabrication.It then effectively presents universal strategies to overcome the mentioned problems.Moreover,this review article examines various printing techniques that can be used to improve PSCs,emphasizing their benefits like low-cost components and procedures.Several printing processes are covered in the discussion,such as slot-die coating,spray coating,inkjet printing,doctor-blade coating,roll-to-roll printing,and screen printing.The potential uses of PSCs for the implementation of greenhouses,building-integrated photovoltaic systems,and indoor light energy harvesting.These uses highlight the adaptability of PSCs and demonstrate their ability to transform energy production technologies.Additionally,this review highlights the special qualities of perovskite materials that present chances to surpass silicon solar cells'efficiency restrictions and get close to the Shockley-Queisser limit.In conclusion,the current review provides a brief overview of recent developments,existing challenges,and opportunities of PSCs.It provides a thorough understanding of the merits of highly efficient PSCs fabricated by adopting printing methods to tackle stability problems along with facile fabrication of PSCs using simplified and cost-effective strategies.
文摘In this study,COMSOL v5.2 Multiphysics software was utilized to perform coupled neutronics and thermal–hydraulics simulations of a molten salt fast reactor,and the SCALE v6.1 code package was utilized to generate the homogenized cross-section data library.The library’s 238 cross-section groups were categorized into nine groups for the simulations in this study.The results of the COMSOL model under no fuel flow conditions were verified using the SCALE v6.1 code results,and the results of the neutronics and thermal–hydraulics simulations were compared to the results of previously published studies.The results indicated that the COMSOL model that includes the cross-section library generated by the SCALE v6.1 code package is suitable for the steady-state analysis and design assessment of molten salt fast reactors.Subsequently,this model was utilized to investigate the neutronics and thermal–hydraulics behaviors of the reactor.Multiple designs were simulated and analyzed in this model,and the results indicated that even if the wall of the core is curved,hot spots occur in the upper and lower portions of the core’s center near the reflectors.A new design was proposed that utilizes a flow rate distribution system,and the simulation results of this design showed that the maximum temperature in the core was approximately 1032 K and no hot spots occurred.
基金Taif University Researchers Supporting Project number(TURSP-2020/275),Taif University,Taif,Saudi Arabia.
文摘In this paper,a new approach is devoted to find novel analytical and approximate solutions to the damped quadratic nonlinear Helmholtz equation(HE)in terms of the Weiersrtrass elliptic function.The exact solution for undamped HE(integrable case)and approximate/semi-analytical solution to the damped HE(non-integrable case)are given for any arbitrary initial conditions.As a special case,the necessary and sufficient condition for the integrability of the damped HE using an elementary approach is reported.In general,a new ansatz is suggested to find a semi-analytical solution to the non-integrable case in the form of Weierstrass elliptic function.In addition,the relation between the Weierstrass and Jacobian elliptic functions solutions to the integrable case will be derived in details.Also,we will make a comparison between the semi-analytical solution and the approximate numerical solutions via using Runge-Kutta fourth-order method,finite difference method,and homotopy perturbation method for the first-two approximations.Furthermore,the maximum distance errors between the approximate/semi-analytical solution and the approximate numerical solutions will be estimated.As real applications,the obtained solutions will be devoted to describe the characteristics behavior of the oscillations in RLC series circuits and in various plasma models such as electronegative complex plasma model.
文摘The present paper is basically written as a non-apologetic strong defence of the thesis that computation is part and parcel of a physical theory and by no means a mere numerical evaluation of the prediction of a theory which comes towards the end. Various general considerations as well as specific examples are given to illustrate and support our arguments. These examples range from the practical aspect to almost esoteric considerations but at the end, everything converges towards a unity of theory and computation presented in the form of modern fractal logic and transfinite quantum field theory in a Cantorian spacetime. It is true that all our examples are taken from physics but our discussion is applicable in equal measure to a much wider aspect of life.
文摘The present note is basically an announcement of a theoretical and experimental resolution of one of the most basic fundamental problems of physics, namely the very existence and reality of the Aether [1-11]. This is not only basic philosophy of science or insightful results in theoretical physics and cosmology [1-24] but more than that because it may lead to actually realizing the futuristic dream of free energy [25-28]. Our mathematical and indirect experimental verdict is that the Aether exists and it can be equated to the empty set of pure mathematics [3, 12-16]. More precisely the Aether may be understood for all mathematical and physical purposes as being identical to the empty set [8-14] underlying the Penrose fractal tessellation universe [17] which obeys the A. Connes’ corresponding dimensional function of his noncommutative geometry [18-21].
文摘At its most basic level physics starts with space-time topology and geometry. On the other hand topology’s and geometry’s simplest and most basic elements are random Cantor sets. It follows then that nonlinear dynamics i.e. deterministic chaos and fractal geometry is the best mathematical theory to apply to the problems of high energy particle physics and cosmology. In the present work we give a short survey of some recent achievements of applying nonlinear dynamics to notoriously difficult subjects such as quantum entanglement as well as the origin and true nature of dark energy, negative absolute temperature and the fractal meaning of the constancy of the speed of light.
文摘A straightforward simple proof is given that dark energy is the natural conse-quence of a quantum disentanglement physical process. Thus while the ordinary energy density of the cosmos is equal to half that of Hardy’s quantum probability of Entanglement i.e. where , the density of cosmic dark energy is consequently one minus divided by two i.e. . This result is in full agreement with all the numerous previous theoretical predictions as well as being in remarkable agreement with the overwhelming majority of cosmic accurate measurements and observations.
文摘By religiously adhering to physics in spacetime and taking the final verdict of N.D. Mermin’s Ithaca interpretation of quantum mechanics seriously, Hardy’s paradox is completely resolved. It is then concluded that logical and mathematically consistent physical theories must be put in spacetime related formalism such as noncommutative geometry and E-infinity theory to avoid quantum paradoxes. At a minimum, we should employ the philosophy behind consistent quantum interpretation such as that of the famous Ithaca interpretation of D. Mermin.
文摘Schrfdinger＇s equation is one the equations that mark the beginnings of the systematic quantum physics. It was shown that it follows from the Dirac＇s equation and the relationship with classical physics, i.e. with classical field theory was established. The subject of this work is the relationship between classical relativistic physics and the quantum physics. Investigation carded out in this work, shows that the free electromagnetic field, spinor Dirac＇s field without mass, spinor Dirac＇s field with mass, and some other fields are described by the same vibrational formulation. The conditions that a field be described by Maxwell＇s equations of motion are given in this work, and some solutions of these conditions are also given. Non-relativistic approximation of the equations of the non-quantified field are the Schrōdinger＇s equations. Dirac＇s equation as a special case, contains Maxwell＇s equations and the Schrōdinger＇s equation.
