High-entropy materials have attracted considerable attention in recent years owing to their unique structural characteristics,tailorable chemical composition,and tunable functional properties.In this study,the concept...High-entropy materials have attracted considerable attention in recent years owing to their unique structural characteristics,tailorable chemical composition,and tunable functional properties.In this study,the concept of entropy-mediated phase stabilization was combined with strongly correlated electron systems to achieve directional property control in single-phase manganites.As Ca and Cr are sequentially doped into(Pr_(0.25)La_(0.25)Nd_(0.25)Sm_(0.25))MnO_(3) at specific contents,the original weak ferromagnetic(FM)state with a spin-canted antiferromagnetic(AFM)background transforms into the charge-ordered AFM state,and then further transitions to the intense FM-AFM competition state.Magnetic state evolution also causes significant changes in electrical properties,highlighting the complex magnetoelectronic phase diagram of this system.Under specific doping conditions,the system exhibits a temperature-induced metamagnetic transition and a significant magnetocaloric effect,demonstrating interesting properties brought about by magnetic phase transitions.The complex magnetoelectric behavior induced by the coexistence and competition of multiple interactions is discussed by combining microstructural characterization with a magnetic theory framework.This study explores a method for effectively manipulating the physical properties of manganites based on the high-entropy concept,which is conducive to the development of new functional materials with kaleidoscopic characteristics.展开更多
BACKGROUND The prominent symptoms of chronic pelvic pain syndrome(CPPS)are urogenital pain,lower urinary tract symptoms,psychological problems,and sexual dysfunction.Traditional pharmacological treatments have poor ef...BACKGROUND The prominent symptoms of chronic pelvic pain syndrome(CPPS)are urogenital pain,lower urinary tract symptoms,psychological problems,and sexual dysfunction.Traditional pharmacological treatments have poor efficacy and more untoward reaction and complications.Magnetic vibration magnetoelectric therapy is a non-invasive form of physiotherapy.Nevertheless,its effectiveness in improving urinary discomfort and relieving pain in patients requires further exploration.AIM To investigate the clinical efficacy of the magnetic vibration magnetoelectric therapy instrument in the treatment of chronic prostatitis(CP)/CPPS.METHODS Seventy patients with CP/CPPS were collected from the outpatient clinic and ward of the Department of Male Medicine,Jiangsu Province Hospital of Traditional Chinese Medicine,and were treated with magnetic vibration magnetoelectric therapy once a day for a period of 14 d.National Institutes of healthchronic prostatitis symptom index(NIH-CPSI),international index of erectile function 5(IIEF-5),premature ejaculation diagnostic tool(PEDT),generalized anxiety disorder(GAD),patient health questionnaire,the pain catastrophizing scale(PCS)and traditional Chinese medicine syndrome(TCMS)scores were performed before and after treatment.RESULTS The total effective rate of treatment was 58.5%,and the total NIH-CPSI score,pain symptoms,voiding symptoms,quality of life,IIEF-5,PEDT,GAD,PCS and TCMS scores all decreased significantly(P<0.05).CONCLUSION Magnetic vibration magnetotherapy is effective in improving urinary discomfort,relieving pain,improving quality of life,improving sexual dysfunction and relieving negative emotions such as anxiety in patients with CP/CPPS.展开更多
Manipulating strain mode and degree that can be applied to epitaxial complex oxide thin films have been a cornerstone of strain engineering.In recent years,lift-off and transfer technology of the epitaxial oxide thin ...Manipulating strain mode and degree that can be applied to epitaxial complex oxide thin films have been a cornerstone of strain engineering.In recent years,lift-off and transfer technology of the epitaxial oxide thin films have been developed that enabled the integration of heterostructures without the limitation of material types and crystal orientations.Moreover,twisted integration would provide a more interesting strategy in artificial magnetoelectric heterostructures.A specific twist angle between the ferroelectric and ferromagnetic oxide layers corresponds to the distinct strain regulation modes in the magnetoelectric coupling process,which could provide some insight in to the physical phenomena.In this work,the La_(0.67)Sr_(0.33)MnO_(3)(001)/0.7Pb(Mg_(1/3)Nb_(2/3))O_(3)-0.3PbTiO_(3)(011)(LSMO/PMN-PT)heterostructures with 45.and 0.twist angles were assembled via water-etching and transfer process.The transferred LSMO films exhibit a fourfold magnetic anisotropy with easy axis along LSMO<110>.A coexistence of uniaxial and fourfold magnetic anisotropy with LSMO[110]easy axis is observed for the 45°Sample by applying a 7.2 kV cm^(−1)electrical field,significantly different from a uniaxial anisotropy with LSMO[100]easy axis for the 0°Sample.The fitting of the ferromagnetic resonance field reveals that the strain coupling generated by the 45°twist angle causes different lattice distortion of LSMO,thereby enhancing both the fourfold and uniaxial anisotropy.This work confirms the twisting degrees of freedom for magnetoelectric coupling and opens opportunities for fabricating artificial magnetoelectric heterostructures.展开更多
CoFe204/Pb（Zr0.53Ti0.47）O3 （CFO/PZT） magnetoelectric composite thin films of 2-2 type structure had been prepared onto Pt/Ti/SiO2/Si substrate by a sol-gel process and spin coat- ing technique. The structure of th...CoFe204/Pb（Zr0.53Ti0.47）O3 （CFO/PZT） magnetoelectric composite thin films of 2-2 type structure had been prepared onto Pt/Ti/SiO2/Si substrate by a sol-gel process and spin coat- ing technique. The structure of the prepared thin film is substrate/PZT/CFO/PZT/CFO. Two CFO ferromagnetic layers are separated from each other by a thin PZT layer. The upper CFO layer is magnetostatically coupled with the lower CFO layer. Subsequent scan- ning electron microscopy （SEM） investigations show that the prepared thin films exhibit good morphologies and compact structure, and cross-sectional micrographs clearly display a multilayered nanostructure of multilayered thin films. The composite thin films exhibit both good magnetic and ferroelectric properties. The spacing between ferromagnetic layers can be varied by adjusting the thickness of intermediate PZT layer. It is found that the strength of magnetostatic coupling has a great impact on magnetoelectric properties of composite thin films, i.e., the magnetoelectric voltage coefficient of composite thin film tends to increase with the decreasing of pacing between two neighboring CFO ferromagnetic layers as a result of magnetostatic coupling effect.展开更多
This paper presents a new device integrating a nonlinear vibration absorber with a levitation magnetoelectric energy harvester for whole-spacecraft systems. This device effectively reduces vibration and has a stronger...This paper presents a new device integrating a nonlinear vibration absorber with a levitation magnetoelectric energy harvester for whole-spacecraft systems. This device effectively reduces vibration and has a stronger energy harvesting capability than the existing systems. It harvests energy from a wide frequency range and has a high output voltage. The harvested energy is determined by magnetic field strength, excitation frequency, and resistive load. The change in the magnetic field strength has the least impact on the output voltage. The vibration reduction effects and harvested energy of the system are analyzed with an approximate analytical method that combines the harmonic balance approach and the pseudo-arclength continuation algorithm. The results of the Runge-Kutta method are nearly consistent with those of the approximate analytical method. Moreover, the effects of the excitation frequency, resistive load, and parameters of the nonlinear energy sink on the system vibration response and energy harvesting are analyzed.展开更多
Single-phase multiferroic BiFeO3 and Bi（0.9）（La/Nd）（0.1）FeO3（doped with rare earth ions La-（3＋） and Nd-（3＋）） films grown on（111）-Pt/Ti/SiO2/Si substrate were prepared via sol-gel method and a subsequen...Single-phase multiferroic BiFeO3 and Bi（0.9）（La/Nd）（0.1）FeO3（doped with rare earth ions La-（3＋） and Nd-（3＋）） films grown on（111）-Pt/Ti/SiO2/Si substrate were prepared via sol-gel method and a subsequent rapid thermal process. The phase composition, microstructure, ferroelectric, dielectric, ferromagnetic properties were investigated, and meanwhile, the in-plane magnetoelectric（ME） coupling effects of the films were reported and studied for the first time in this work. Structural characterization by X-ray diffraction and scanning electron microscopy showed that both BiFeO3 and Bi（0.9）（La/Nd）（0.1）FeO3 exhabited a rhombohedral structure with（111） preferred orientation. The results of the physical properties indicated that the introduction of rare earth ions improved significantly the polarization, magnetization and dielectric properties than the undoped BiFeO3 crystals, and it enhanced effectively the in-plane ME coupling（the ME coupling coefficient αE increased from 0.13 in the pure BiFeO3 to 0.21 in Bi（0.9）La（0.1）FeO3 and 0.34 V/（Oe·cm） in Bi（0.9）Nd（0.1）FeO3）. The mechanism of these phenomena was investigated systematically.展开更多
The effects of linear electromagnetic stirring (EMS) on the solidification structure of billet were investigated by experiments, and the electromagnetic field and the flow field during the stirring process were analyz...The effects of linear electromagnetic stirring (EMS) on the solidification structure of billet were investigated by experiments, and the electromagnetic field and the flow field during the stirring process were analyzed by numerical simulation. The results show that the billet of almost 100% equiaxed grains can be obtained by applying linear EMS at the maximum intensity of 1414 A·Hz1/2, while the maximum electromagnetic force and the maximum velocity in the molten steel are 6386 N·m-3 and 0.22 m·s-1 respectively. It is shown that in the pulsating electromagnetic force which is perpendicular to the movement of the molten steel is an important factor of increasing the equiaxed zone ration in the solidification structure, which further prevents the appearance of white band and internal defects.展开更多
Multiferroic nanomaterials have attracted great interest due to simultaneous two or more properties such as ferroelectricity,ferromagnetism,and ferroelasticity,which can promise a broad application in multifunctional,...Multiferroic nanomaterials have attracted great interest due to simultaneous two or more properties such as ferroelectricity,ferromagnetism,and ferroelasticity,which can promise a broad application in multifunctional,lowpower consumption,environmentally friendly devices.Bismuth ferrite(BiFeO3,BFO)exhibits both(anti)ferromagnetic and ferroelectric properties at room temperature.Thus,it has played an increasingly important role in multiferroic system.In this review,we systematically discussed the developments of BFO nanomaterials including morphology,structures,properties,and potential applications in multiferroic devices with novel functions.Even the opportunities and challenges were all analyzed and summarized.We hope this review can act as an updating and encourage more researchers to push on the development of BFO nanomaterials in the future.展开更多
It is theoretically considered the propagation (first evidence) of new dispersive shear-horizontal (SH) acoustic waves in the piezoelectromagnetic (magnetoelectroelastic) composite plates. The studied two-phase compos...It is theoretically considered the propagation (first evidence) of new dispersive shear-horizontal (SH) acoustic waves in the piezoelectromagnetic (magnetoelectroelastic) composite plates. The studied two-phase composites (BaTiO3-CoFe2O4 and PZT-5H-Terfenol-D) possess the piezoelectric phase (BaTiO3, PZT-5H) and the piezomagnetic phase (CoFe2O4, Terfenol-D). The mechanical, electrical, and magnetic boundary conditions applied to both the upper and lower free surfaces of the plate are as follows: the mechanically free, electrically closed, and magnetically closed surfaces. As a result, the fundamental modes of two new dispersive SH-waves recently discovered in book [Zakharenko, A.A. (2012) ISBN: 978-3-659-30943-4] were numerically calculated. It was found that for large values of normalized plate thickness kd (k and d are the wavenumber and plate half-thickness, respectively) the velocities of both the new dispersive SH-waves can approach the nondispersive SH-SAW velocity of the piezoelectric exchange surface Melkumyan (PEESM) wave. It was also discussed that for small values of kd, the experimental study of the new dispersive SH-waves can be preferable in comparison with the nondispersive PEESM wave. The obtained results can be constructive for creation of various technical devices based on (non)dispersive SH-waves and two-phase smart materials. The new dispersive SH-waves propagating in the plates can be also employed for nondestructive testing and evaluation. Also, it is obvious that the plates can be used in technical devices instead of the corresponding bulk samples for further miniaturization.展开更多
Multiferroic bi-layer Fe/BaTiO3 （BTO） thin films were successfully deposited on Pt（200）/MgO（100） substrates using ion beam sputter deposition （1BSD）, and the mutiferroic properties were studied at room tempera...Multiferroic bi-layer Fe/BaTiO3 （BTO） thin films were successfully deposited on Pt（200）/MgO（100） substrates using ion beam sputter deposition （1BSD）, and the mutiferroic properties were studied at room temperature. X-ray diffraction （XRD） analyses showed that BTO films were c-axis oriented and epitaxially grown on platinum coated MgO substrates, and （110） epitaxial Fe films were subsequently grown on （001） BTO films. Fe/BTO bi-layer films showed good ferroelectric and ferromagnetic properties at room temperature and the multiferroic coupling was observed, which should be attributed to the hybridization of Fe and Ti occurring at the ferromagnetic-ferroelectric interface.展开更多
Magnetoelectric （ME） layered Ni/PZT/Ni composites with arc shape have been prepared by using electroless deposition. The ME effect is measured by applying both constant and alternating magnetic fields in longitudina...Magnetoelectric （ME） layered Ni/PZT/Ni composites with arc shape have been prepared by using electroless deposition. The ME effect is measured by applying both constant and alternating magnetic fields in longitudinal and transverse directions. The longitudinal ME voltage coefficient is much larger than the transverse one. With the increase of arc length or decrease of curvature, the resonance frequency of layered arc Ni/PZT/Ni composites gradually decreases, while the maximum of the ME voltage coefficient of the composites increases monotonously. The influence of the arc length and the curvature on ME coupling is discussed. The flat interface between the ferromagnetic and the piezoelectric phases in layered ME composites is believed to provide large ME voltage coefficient.展开更多
Y-type hexaferrites with tunable conical magnetic structures are promising single-phase multiferroics that exhibit large magnetoelectric effects.We have investigated the influence of Co substitution on the magnetoelec...Y-type hexaferrites with tunable conical magnetic structures are promising single-phase multiferroics that exhibit large magnetoelectric effects.We have investigated the influence of Co substitution on the magnetoelectric properties in the Y-type hexaferrites Ba_(0.3)Sr_(1.7)Co_(x)Mg_(2-x)Fe_(12)O_(22)(x=0.0,0.4,1.0,1.6).The spin-induced electric polarization can be reversed by applying a low magnetic field for all the samples.The magnetoelectric phase diagrams of Ba_(0.3)Sr_(1.7)Co_(x)Mg_(2-x)Fe_(12)O_(22)are obtained based on the measurements of magnetic field dependence of dielectric constant at selected temperatures.It is found that the substitution of Co ions can preserve the ferroelectric phase up to a higher temperature,and thus is beneficial for achieving single-phase multiferroics at room temperature.展开更多
This paper presents a theoretical model for predicting and tuning magnetoelectric(ME)effect of ring-shaped composites,in which stress boundary conditions are empoyed and the multi-field coupling property of giant magn...This paper presents a theoretical model for predicting and tuning magnetoelectric(ME)effect of ring-shaped composites,in which stress boundary conditions are empoyed and the multi-field coupling property of giant magnetostrictive materials are taken into account.A linear analytical solutions for the closed-and open-circuit ME voltages are derived simultaneously using mechanical differential equations,interface and boundary conditions,and electrical equations.For nonlinear ME coupling effect,the nonlinear multi-field coupling constitutive equation is reduced to an equivalent form by expanding the strains as a Taylor series in the vicinity of bias magnetic field.Sequentially,the linear model is generalized to a nonlinear one involving the field-dependent material parameters.The results show that setting a stress-free condition is beneficial for reducing resonance frequency while applying clamped conditions on the inner and outer boundaries may improve the maximum output power density.In addition,performing stress conditions on one of the boundaries may enhance ME coupling significantly,without changing the corresponding resonance frequency and optimal resistance.When external stimuli like bias magnetic field and pre-stress are applied to the ring-shaped composites,a novel dual peak phenomenon in the ME voltage curve around resonance frequencies is revealed theoretically,indicating that strong ME coupling may be achieved within a wider bias field region.Eventually,the mutual coordination of the bias field and pre-stress may enhance ME coupling as well as tuning the resonance frequency,and thus is pivotal for tunable control of ME energy harvesters.The proposed model can be applied to design high-performance energy harvesters by manipulating the mechanical conditions and external stimuli.展开更多
Multiferroic NiFe2O4 （NFO）-BaTiO3 （BTO） bilayered thin films are epitaxially grown on （001） Nb-doped SrTiO3 （STO） substrates by pulsed-laser deposition （PLD）. Different growth sequences of NFO and BTO on the...Multiferroic NiFe2O4 （NFO）-BaTiO3 （BTO） bilayered thin films are epitaxially grown on （001） Nb-doped SrTiO3 （STO） substrates by pulsed-laser deposition （PLD）. Different growth sequences of NFO and BTO on the substrate yield two kinds of epitaxial heterostructures with （001）-orientation, i.e. （001）-NFO/（001）-BTO/substrate and （001）- BTO/（001）-NFO/substrate. Microstructure studies from x-ray diffraction （XRD） and electron microscopies show differences between these two heterostructures, which result in different multiferroic behaviours. The heterostructured composite films exhibit good coexistence of both ferroelectric and ferromagnetic properties, in particular, obvious magnetoelectric （ME） effect on coupling response.展开更多
Metal-organic frameworks(MOFs)are considered as a novel type of microwave absorption(MA)material owing to the sufficient pore structure,diverse configurations,and easy-to-control magnetic properties.However,their evol...Metal-organic frameworks(MOFs)are considered as a novel type of microwave absorption(MA)material owing to the sufficient pore structure,diverse configurations,and easy-to-control magnetic properties.However,their evolution is limited by the imperfect impedance matching conditions caused by the undesirable microstructure.Herein,two types of novel porous coral-like carbon/Co_(3)O_(4)and carbon/Co composites have been effectively fabricated for the first time by a facile heat treatment process of precursor Co-MOF-71.The graphitization degree,magnetic property and MA ability of the product can be effortlessly tuned by altering the heat treatment temperature of Co-MOF-71.Remarkably,S500(Co-MOF-71 calcined at 500℃)composite displays strong and multi-frequency absorption performance,whose minimum reflection loss(RL)value achieves-36.4 d B with an absorbing thickness of 3.0 mm and attains an effective absorbing bandwidth(RL≤-10 dB)of 5.76 GHz(almost covers whole Ku band)at a thinner coating thickness of 2.5 mm.Such superb MA ability has roots in the coral-like structure derived from the layer Co-MOF-71,sufficient electromagnetic loss.This work ameliorates the MA ability of MOFs through a special nanostructural design,which provides a fresh way for the preparation of novel MA materials.展开更多
Ferromagnetic shape memory alloys, which undergo the martensitic transformation, are famous multifunctional materials. They exhibit many interesting magnetic properties around the martensitic transformation temperatur...Ferromagnetic shape memory alloys, which undergo the martensitic transformation, are famous multifunctional materials. They exhibit many interesting magnetic properties around the martensitic transformation temperature due to the strong coupling between magnetism and structure. Tuning magnetic phase transition and optimizing the magnetic effects in these alloys are of great importance. In this paper, the regulation of martensitic transformation and the investigation of some related magnetic effects in Ni–Mn-based alloys are reviewed based on our recent research results.展开更多
The compounds of iron substituted yttrium oxide systems have been prepared for the importance in the field of magneto electric materials.The polycrystalline samples of Y2–xFexO3–y(x=0.1,0.2) were prepared by solid-s...The compounds of iron substituted yttrium oxide systems have been prepared for the importance in the field of magneto electric materials.The polycrystalline samples of Y2–xFexO3–y(x=0.1,0.2) were prepared by solid-state reaction method.The single-phase formation of these compounds was confirmed by X-ray diffraction studies.It was found that the samples crystallized in tetragonal phase and the lattice parameters were calculated as a=1.0559(7) nm,c=1.0832(9) nm for Y1.9Fe0.1O3–y and a=1.0545(6) nm,c=1.0841(8)...展开更多
The frequency dependence of the magnetoelectric effect in a magnetostrictive-piezoelectric heterostructure is theoretically studied by solving combined magnetic, elastic, and electric equations with boundary condition...The frequency dependence of the magnetoelectric effect in a magnetostrictive-piezoelectric heterostructure is theoretically studied by solving combined magnetic, elastic, and electric equations with boundary conditions. Both the mechanical coupling coefficient and the losses of the magnetostrictive and piezoelectric phases are taken into account. The numerical result indicates that the magnetoelectric coefficient and the resonance frequency are determined by the mechanical coupling coefficient, losses, and geometric parameters. Moreover, at the electromechanical resonance frequency, the module of the magnetoelectric coefficient is mostly contributed by the imaginary part. The relationship between the real and the imaginary parts of the magnetoelectric coefficient fit well to the Cole–Cole circle. The magnetostrictive-piezoelectric heterostructure has a great potential application as miniature and no-secondary coil solid-state transformers.展开更多
Multiferroic composite structures are widely used in sensing,driving and communication.The study of their magnetoelectric(ME)behavior under various excitations is crucial.This study investigates the nonlinear ME influ...Multiferroic composite structures are widely used in sensing,driving and communication.The study of their magnetoelectric(ME)behavior under various excitations is crucial.This study investigates the nonlinear ME influence of a multilayer composite ring structure consisting of Terfenol-D(TD)magnetostrictive and lead zirconate titanate(PZT)piezoelectric rings utilizing a multiphysics field modeling framework based on the fully coupled finite element method.The ME coupling coefficient of the PZT/TD concentric composite ring is predicted using the linear piezoelectric constitutive model and the nonlinear magnetostrictive constitutive model,which is congruent to the experimental data.The effect of the interface area of a trilayered structure on the coupling performance at the resonant frequency is investigated,considering the magnitude and frequency of the magnetic field and keeping the material ratio constant.The ME coupling coefficient of a trilayered structure is larger than that of a bilayered structure with the same material ratio,and the maximum ME coupling coefficient of a trilayered structure increases nonlinearly with the increase in the interface area.At the resonant frequency,the structure's ME coupling performance is considerably improved.An optimization technique based on structural geometric design and magnetic field control is presented to optimize the ME coupling coefficient.展开更多
In order to study the transmission efficiency of engine and optimize the structure of driving wheel,the rotational speed storage test device of driving wheel in tracked vehicle based on magnetoelectric sensor was desi...In order to study the transmission efficiency of engine and optimize the structure of driving wheel,the rotational speed storage test device of driving wheel in tracked vehicle based on magnetoelectric sensor was designed.The device consisted of a mounting bracket,a sensor and a tester.The mounting bracket was installed in vehicle body after fixing the tester and sensor to mounting bracket beside the driving wheel.Using the storage test instrument,the wireless trigger technology was applied to synchronously record and stored the rotational speed data of the driving wheel in tracked vehicle.After the experiment was finished,the data was read out through the upper computer.Both valid data and satisfactory results were obtained through both simulated and actual vehicle tests.展开更多
基金supported by the National Natural Science Foundation of China(Nos.12074204,12374258 and 12404326)the Natural Science Foundation of Inner Mongolia Autonomous Region of China(Nos.2022ZD06 and 2023QN01008)+3 种基金the Program for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region(No.NMGIRT2203)the Research Program of Science and Technology at Universities of Inner Mongolia Autonomous Region(No.NJZZ23024)the Fundamental Research Funds for the Inner Mongolia Normal University(No.2023JBYJ015)the Funds for Reform and Development of Local Universities Supported by the Central Government(Cultivation of First-Class Disciplines in Physics).
文摘High-entropy materials have attracted considerable attention in recent years owing to their unique structural characteristics,tailorable chemical composition,and tunable functional properties.In this study,the concept of entropy-mediated phase stabilization was combined with strongly correlated electron systems to achieve directional property control in single-phase manganites.As Ca and Cr are sequentially doped into(Pr_(0.25)La_(0.25)Nd_(0.25)Sm_(0.25))MnO_(3) at specific contents,the original weak ferromagnetic(FM)state with a spin-canted antiferromagnetic(AFM)background transforms into the charge-ordered AFM state,and then further transitions to the intense FM-AFM competition state.Magnetic state evolution also causes significant changes in electrical properties,highlighting the complex magnetoelectronic phase diagram of this system.Under specific doping conditions,the system exhibits a temperature-induced metamagnetic transition and a significant magnetocaloric effect,demonstrating interesting properties brought about by magnetic phase transitions.The complex magnetoelectric behavior induced by the coexistence and competition of multiple interactions is discussed by combining microstructural characterization with a magnetic theory framework.This study explores a method for effectively manipulating the physical properties of manganites based on the high-entropy concept,which is conducive to the development of new functional materials with kaleidoscopic characteristics.
文摘BACKGROUND The prominent symptoms of chronic pelvic pain syndrome(CPPS)are urogenital pain,lower urinary tract symptoms,psychological problems,and sexual dysfunction.Traditional pharmacological treatments have poor efficacy and more untoward reaction and complications.Magnetic vibration magnetoelectric therapy is a non-invasive form of physiotherapy.Nevertheless,its effectiveness in improving urinary discomfort and relieving pain in patients requires further exploration.AIM To investigate the clinical efficacy of the magnetic vibration magnetoelectric therapy instrument in the treatment of chronic prostatitis(CP)/CPPS.METHODS Seventy patients with CP/CPPS were collected from the outpatient clinic and ward of the Department of Male Medicine,Jiangsu Province Hospital of Traditional Chinese Medicine,and were treated with magnetic vibration magnetoelectric therapy once a day for a period of 14 d.National Institutes of healthchronic prostatitis symptom index(NIH-CPSI),international index of erectile function 5(IIEF-5),premature ejaculation diagnostic tool(PEDT),generalized anxiety disorder(GAD),patient health questionnaire,the pain catastrophizing scale(PCS)and traditional Chinese medicine syndrome(TCMS)scores were performed before and after treatment.RESULTS The total effective rate of treatment was 58.5%,and the total NIH-CPSI score,pain symptoms,voiding symptoms,quality of life,IIEF-5,PEDT,GAD,PCS and TCMS scores all decreased significantly(P<0.05).CONCLUSION Magnetic vibration magnetotherapy is effective in improving urinary discomfort,relieving pain,improving quality of life,improving sexual dysfunction and relieving negative emotions such as anxiety in patients with CP/CPPS.
基金supported by the National Key Research and Development Program of China (Grant No. 2021YFB3201800)Natural Science Foundation of China (Grant Nos. U22A2019, 91964109, 52372123)+3 种基金State Key Laboratory for Mechanical Behavior of Materials (No. 20222405)Innovation Capability Support Program of Shaanxi (Grant No. 2021TD-12)National 111 Project of China (B14040)support from the Instrumental Analysis Center of Xi’an Jiaotong University
文摘Manipulating strain mode and degree that can be applied to epitaxial complex oxide thin films have been a cornerstone of strain engineering.In recent years,lift-off and transfer technology of the epitaxial oxide thin films have been developed that enabled the integration of heterostructures without the limitation of material types and crystal orientations.Moreover,twisted integration would provide a more interesting strategy in artificial magnetoelectric heterostructures.A specific twist angle between the ferroelectric and ferromagnetic oxide layers corresponds to the distinct strain regulation modes in the magnetoelectric coupling process,which could provide some insight in to the physical phenomena.In this work,the La_(0.67)Sr_(0.33)MnO_(3)(001)/0.7Pb(Mg_(1/3)Nb_(2/3))O_(3)-0.3PbTiO_(3)(011)(LSMO/PMN-PT)heterostructures with 45.and 0.twist angles were assembled via water-etching and transfer process.The transferred LSMO films exhibit a fourfold magnetic anisotropy with easy axis along LSMO<110>.A coexistence of uniaxial and fourfold magnetic anisotropy with LSMO[110]easy axis is observed for the 45°Sample by applying a 7.2 kV cm^(−1)electrical field,significantly different from a uniaxial anisotropy with LSMO[100]easy axis for the 0°Sample.The fitting of the ferromagnetic resonance field reveals that the strain coupling generated by the 45°twist angle causes different lattice distortion of LSMO,thereby enhancing both the fourfold and uniaxial anisotropy.This work confirms the twisting degrees of freedom for magnetoelectric coupling and opens opportunities for fabricating artificial magnetoelectric heterostructures.
文摘CoFe204/Pb（Zr0.53Ti0.47）O3 （CFO/PZT） magnetoelectric composite thin films of 2-2 type structure had been prepared onto Pt/Ti/SiO2/Si substrate by a sol-gel process and spin coat- ing technique. The structure of the prepared thin film is substrate/PZT/CFO/PZT/CFO. Two CFO ferromagnetic layers are separated from each other by a thin PZT layer. The upper CFO layer is magnetostatically coupled with the lower CFO layer. Subsequent scan- ning electron microscopy （SEM） investigations show that the prepared thin films exhibit good morphologies and compact structure, and cross-sectional micrographs clearly display a multilayered nanostructure of multilayered thin films. The composite thin films exhibit both good magnetic and ferroelectric properties. The spacing between ferromagnetic layers can be varied by adjusting the thickness of intermediate PZT layer. It is found that the strength of magnetostatic coupling has a great impact on magnetoelectric properties of composite thin films, i.e., the magnetoelectric voltage coefficient of composite thin film tends to increase with the decreasing of pacing between two neighboring CFO ferromagnetic layers as a result of magnetostatic coupling effect.
基金the National Natural Science Foundation of China (Project No. 11772205)the Training Project of Liaoning Provincial Higher Education Institutions in Domestic and Overseas (Project No. 2018LNGXGJWPY-YB008)the Scientific Research Fund of Liaoning Provincial Education Department (Project No. L201703).
文摘This paper presents a new device integrating a nonlinear vibration absorber with a levitation magnetoelectric energy harvester for whole-spacecraft systems. This device effectively reduces vibration and has a stronger energy harvesting capability than the existing systems. It harvests energy from a wide frequency range and has a high output voltage. The harvested energy is determined by magnetic field strength, excitation frequency, and resistive load. The change in the magnetic field strength has the least impact on the output voltage. The vibration reduction effects and harvested energy of the system are analyzed with an approximate analytical method that combines the harmonic balance approach and the pseudo-arclength continuation algorithm. The results of the Runge-Kutta method are nearly consistent with those of the approximate analytical method. Moreover, the effects of the excitation frequency, resistive load, and parameters of the nonlinear energy sink on the system vibration response and energy harvesting are analyzed.
基金Project supported by National Natural Science Foundation of China(51462003)Science Research Fund of Guizhou Province,China(2015-4006,2014-001,2014-7612)+1 种基金the Introduced Talents Funds of Guizhou University(2014-30)Master’s Innovation Funds of Guizhou University(2016065)
文摘Single-phase multiferroic BiFeO3 and Bi（0.9）（La/Nd）（0.1）FeO3（doped with rare earth ions La-（3＋） and Nd-（3＋）） films grown on（111）-Pt/Ti/SiO2/Si substrate were prepared via sol-gel method and a subsequent rapid thermal process. The phase composition, microstructure, ferroelectric, dielectric, ferromagnetic properties were investigated, and meanwhile, the in-plane magnetoelectric（ME） coupling effects of the films were reported and studied for the first time in this work. Structural characterization by X-ray diffraction and scanning electron microscopy showed that both BiFeO3 and Bi（0.9）（La/Nd）（0.1）FeO3 exhabited a rhombohedral structure with（111） preferred orientation. The results of the physical properties indicated that the introduction of rare earth ions improved significantly the polarization, magnetization and dielectric properties than the undoped BiFeO3 crystals, and it enhanced effectively the in-plane ME coupling（the ME coupling coefficient αE increased from 0.13 in the pure BiFeO3 to 0.21 in Bi（0.9）La（0.1）FeO3 and 0.34 V/（Oe·cm） in Bi（0.9）Nd（0.1）FeO3）. The mechanism of these phenomena was investigated systematically.
文摘The effects of linear electromagnetic stirring (EMS) on the solidification structure of billet were investigated by experiments, and the electromagnetic field and the flow field during the stirring process were analyzed by numerical simulation. The results show that the billet of almost 100% equiaxed grains can be obtained by applying linear EMS at the maximum intensity of 1414 A·Hz1/2, while the maximum electromagnetic force and the maximum velocity in the molten steel are 6386 N·m-3 and 0.22 m·s-1 respectively. It is shown that in the pulsating electromagnetic force which is perpendicular to the movement of the molten steel is an important factor of increasing the equiaxed zone ration in the solidification structure, which further prevents the appearance of white band and internal defects.
基金the National Key R&D Program of China(Grant No.2016YFA0202701)the National Natural Science Foundation of China(Grant Nos.51472055,51504133)+5 种基金External Cooperation Program of BIC,Chinese Academy of Sciences(Grant No.121411KYS820150028)the 2015 Annual Beijing Talents Fund(Grant No.2015000021223ZK32)Qingdao National Laboratory for Marine Science and Technology(No.2017ASKJ01)the University of Chinese Academy of Sciences(Grant No.Y8540XX2D2)2019 Project of Liaoning Education Department(2019LNJC20)the“thousands talents”program for the pioneer researcher and his innovation team,China.
文摘Multiferroic nanomaterials have attracted great interest due to simultaneous two or more properties such as ferroelectricity,ferromagnetism,and ferroelasticity,which can promise a broad application in multifunctional,lowpower consumption,environmentally friendly devices.Bismuth ferrite(BiFeO3,BFO)exhibits both(anti)ferromagnetic and ferroelectric properties at room temperature.Thus,it has played an increasingly important role in multiferroic system.In this review,we systematically discussed the developments of BFO nanomaterials including morphology,structures,properties,and potential applications in multiferroic devices with novel functions.Even the opportunities and challenges were all analyzed and summarized.We hope this review can act as an updating and encourage more researchers to push on the development of BFO nanomaterials in the future.
文摘It is theoretically considered the propagation (first evidence) of new dispersive shear-horizontal (SH) acoustic waves in the piezoelectromagnetic (magnetoelectroelastic) composite plates. The studied two-phase composites (BaTiO3-CoFe2O4 and PZT-5H-Terfenol-D) possess the piezoelectric phase (BaTiO3, PZT-5H) and the piezomagnetic phase (CoFe2O4, Terfenol-D). The mechanical, electrical, and magnetic boundary conditions applied to both the upper and lower free surfaces of the plate are as follows: the mechanically free, electrically closed, and magnetically closed surfaces. As a result, the fundamental modes of two new dispersive SH-waves recently discovered in book [Zakharenko, A.A. (2012) ISBN: 978-3-659-30943-4] were numerically calculated. It was found that for large values of normalized plate thickness kd (k and d are the wavenumber and plate half-thickness, respectively) the velocities of both the new dispersive SH-waves can approach the nondispersive SH-SAW velocity of the piezoelectric exchange surface Melkumyan (PEESM) wave. It was also discussed that for small values of kd, the experimental study of the new dispersive SH-waves can be preferable in comparison with the nondispersive PEESM wave. The obtained results can be constructive for creation of various technical devices based on (non)dispersive SH-waves and two-phase smart materials. The new dispersive SH-waves propagating in the plates can be also employed for nondestructive testing and evaluation. Also, it is obvious that the plates can be used in technical devices instead of the corresponding bulk samples for further miniaturization.
基金Project supported by the Yeungnam University Research Grant in 2010Project (507111403888) supported by the National Science Foundation of China for International Communication and CooperationProject (50672034) supported by the National Natural Science Foundation of China
文摘Multiferroic bi-layer Fe/BaTiO3 （BTO） thin films were successfully deposited on Pt（200）/MgO（100） substrates using ion beam sputter deposition （1BSD）, and the mutiferroic properties were studied at room temperature. X-ray diffraction （XRD） analyses showed that BTO films were c-axis oriented and epitaxially grown on platinum coated MgO substrates, and （110） epitaxial Fe films were subsequently grown on （001） BTO films. Fe/BTO bi-layer films showed good ferroelectric and ferromagnetic properties at room temperature and the multiferroic coupling was observed, which should be attributed to the hybridization of Fe and Ti occurring at the ferromagnetic-ferroelectric interface.
基金Project supported by the Natural Science Foundation of Jiangsu Province of China (Grant No. BK2010505)the Funding of Jiangsu Innovation Program for Graduate Education (Grant No. CX10B 099Z)
文摘Magnetoelectric （ME） layered Ni/PZT/Ni composites with arc shape have been prepared by using electroless deposition. The ME effect is measured by applying both constant and alternating magnetic fields in longitudinal and transverse directions. The longitudinal ME voltage coefficient is much larger than the transverse one. With the increase of arc length or decrease of curvature, the resonance frequency of layered arc Ni/PZT/Ni composites gradually decreases, while the maximum of the ME voltage coefficient of the composites increases monotonously. The influence of the arc length and the curvature on ME coupling is discussed. The flat interface between the ferromagnetic and the piezoelectric phases in layered ME composites is believed to provide large ME voltage coefficient.
基金Project supported by the National Natural Science Foundation of China(Grant No.51725104)Beijing Natural Science Foundation,China(Grant No.Z180009)。
文摘Y-type hexaferrites with tunable conical magnetic structures are promising single-phase multiferroics that exhibit large magnetoelectric effects.We have investigated the influence of Co substitution on the magnetoelectric properties in the Y-type hexaferrites Ba_(0.3)Sr_(1.7)Co_(x)Mg_(2-x)Fe_(12)O_(22)(x=0.0,0.4,1.0,1.6).The spin-induced electric polarization can be reversed by applying a low magnetic field for all the samples.The magnetoelectric phase diagrams of Ba_(0.3)Sr_(1.7)Co_(x)Mg_(2-x)Fe_(12)O_(22)are obtained based on the measurements of magnetic field dependence of dielectric constant at selected temperatures.It is found that the substitution of Co ions can preserve the ferroelectric phase up to a higher temperature,and thus is beneficial for achieving single-phase multiferroics at room temperature.
基金supported by the National Natural Science Foundation of China(Grant No.11702202)the Fundamental Research Funds for the Central Universities,China(Grant No.JB210410)the the National Natural Science Foundation of China(Grant No.51805401)。
文摘This paper presents a theoretical model for predicting and tuning magnetoelectric(ME)effect of ring-shaped composites,in which stress boundary conditions are empoyed and the multi-field coupling property of giant magnetostrictive materials are taken into account.A linear analytical solutions for the closed-and open-circuit ME voltages are derived simultaneously using mechanical differential equations,interface and boundary conditions,and electrical equations.For nonlinear ME coupling effect,the nonlinear multi-field coupling constitutive equation is reduced to an equivalent form by expanding the strains as a Taylor series in the vicinity of bias magnetic field.Sequentially,the linear model is generalized to a nonlinear one involving the field-dependent material parameters.The results show that setting a stress-free condition is beneficial for reducing resonance frequency while applying clamped conditions on the inner and outer boundaries may improve the maximum output power density.In addition,performing stress conditions on one of the boundaries may enhance ME coupling significantly,without changing the corresponding resonance frequency and optimal resistance.When external stimuli like bias magnetic field and pre-stress are applied to the ring-shaped composites,a novel dual peak phenomenon in the ME voltage curve around resonance frequencies is revealed theoretically,indicating that strong ME coupling may be achieved within a wider bias field region.Eventually,the mutual coordination of the bias field and pre-stress may enhance ME coupling as well as tuning the resonance frequency,and thus is pivotal for tunable control of ME energy harvesters.The proposed model can be applied to design high-performance energy harvesters by manipulating the mechanical conditions and external stimuli.
基金Project supported by the State Key Development Program for Basic Research of China (Grant No 2002CB613303)the National High Technology Research and Development Program for Advanced Materials of China (Grant No 2006AA03Z101)the National Natural Science Foundation of China (Grant Nos 10574078 and 50621201)
文摘Multiferroic NiFe2O4 （NFO）-BaTiO3 （BTO） bilayered thin films are epitaxially grown on （001） Nb-doped SrTiO3 （STO） substrates by pulsed-laser deposition （PLD）. Different growth sequences of NFO and BTO on the substrate yield two kinds of epitaxial heterostructures with （001）-orientation, i.e. （001）-NFO/（001）-BTO/substrate and （001）- BTO/（001）-NFO/substrate. Microstructure studies from x-ray diffraction （XRD） and electron microscopies show differences between these two heterostructures, which result in different multiferroic behaviours. The heterostructured composite films exhibit good coexistence of both ferroelectric and ferromagnetic properties, in particular, obvious magnetoelectric （ME） effect on coupling response.
基金the financial support from the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Metal-organic frameworks(MOFs)are considered as a novel type of microwave absorption(MA)material owing to the sufficient pore structure,diverse configurations,and easy-to-control magnetic properties.However,their evolution is limited by the imperfect impedance matching conditions caused by the undesirable microstructure.Herein,two types of novel porous coral-like carbon/Co_(3)O_(4)and carbon/Co composites have been effectively fabricated for the first time by a facile heat treatment process of precursor Co-MOF-71.The graphitization degree,magnetic property and MA ability of the product can be effortlessly tuned by altering the heat treatment temperature of Co-MOF-71.Remarkably,S500(Co-MOF-71 calcined at 500℃)composite displays strong and multi-frequency absorption performance,whose minimum reflection loss(RL)value achieves-36.4 d B with an absorbing thickness of 3.0 mm and attains an effective absorbing bandwidth(RL≤-10 dB)of 5.76 GHz(almost covers whole Ku band)at a thinner coating thickness of 2.5 mm.Such superb MA ability has roots in the coral-like structure derived from the layer Co-MOF-71,sufficient electromagnetic loss.This work ameliorates the MA ability of MOFs through a special nanostructural design,which provides a fresh way for the preparation of novel MA materials.
基金the National Basic Research Program of China(Grant No.2012CB932304)the National Natural Science Foundation of China(Grant No.U1232210)
文摘Ferromagnetic shape memory alloys, which undergo the martensitic transformation, are famous multifunctional materials. They exhibit many interesting magnetic properties around the martensitic transformation temperature due to the strong coupling between magnetism and structure. Tuning magnetic phase transition and optimizing the magnetic effects in these alloys are of great importance. In this paper, the regulation of martensitic transformation and the investigation of some related magnetic effects in Ni–Mn-based alloys are reviewed based on our recent research results.
文摘The compounds of iron substituted yttrium oxide systems have been prepared for the importance in the field of magneto electric materials.The polycrystalline samples of Y2–xFexO3–y(x=0.1,0.2) were prepared by solid-state reaction method.The single-phase formation of these compounds was confirmed by X-ray diffraction studies.It was found that the samples crystallized in tetragonal phase and the lattice parameters were calculated as a=1.0559(7) nm,c=1.0832(9) nm for Y1.9Fe0.1O3–y and a=1.0545(6) nm,c=1.0841(8)...
文摘The frequency dependence of the magnetoelectric effect in a magnetostrictive-piezoelectric heterostructure is theoretically studied by solving combined magnetic, elastic, and electric equations with boundary conditions. Both the mechanical coupling coefficient and the losses of the magnetostrictive and piezoelectric phases are taken into account. The numerical result indicates that the magnetoelectric coefficient and the resonance frequency are determined by the mechanical coupling coefficient, losses, and geometric parameters. Moreover, at the electromechanical resonance frequency, the module of the magnetoelectric coefficient is mostly contributed by the imaginary part. The relationship between the real and the imaginary parts of the magnetoelectric coefficient fit well to the Cole–Cole circle. The magnetostrictive-piezoelectric heterostructure has a great potential application as miniature and no-secondary coil solid-state transformers.
基金supported by the National Key Research and Development Program of China(2018YFB0703500)the Natural Science Foundation of Beijing(3202001).
文摘Multiferroic composite structures are widely used in sensing,driving and communication.The study of their magnetoelectric(ME)behavior under various excitations is crucial.This study investigates the nonlinear ME influence of a multilayer composite ring structure consisting of Terfenol-D(TD)magnetostrictive and lead zirconate titanate(PZT)piezoelectric rings utilizing a multiphysics field modeling framework based on the fully coupled finite element method.The ME coupling coefficient of the PZT/TD concentric composite ring is predicted using the linear piezoelectric constitutive model and the nonlinear magnetostrictive constitutive model,which is congruent to the experimental data.The effect of the interface area of a trilayered structure on the coupling performance at the resonant frequency is investigated,considering the magnitude and frequency of the magnetic field and keeping the material ratio constant.The ME coupling coefficient of a trilayered structure is larger than that of a bilayered structure with the same material ratio,and the maximum ME coupling coefficient of a trilayered structure increases nonlinearly with the increase in the interface area.At the resonant frequency,the structure's ME coupling performance is considerably improved.An optimization technique based on structural geometric design and magnetic field control is presented to optimize the ME coupling coefficient.
基金Cultivation Programs for Young Scientific Research Personnel of Higher Education Institutions in Shanxi Province(No.2019QPJH18)Fund for“1331 Project”Key Innovative Research Team of Shanxi Province(No.1331KIPT)。
文摘In order to study the transmission efficiency of engine and optimize the structure of driving wheel,the rotational speed storage test device of driving wheel in tracked vehicle based on magnetoelectric sensor was designed.The device consisted of a mounting bracket,a sensor and a tester.The mounting bracket was installed in vehicle body after fixing the tester and sensor to mounting bracket beside the driving wheel.Using the storage test instrument,the wireless trigger technology was applied to synchronously record and stored the rotational speed data of the driving wheel in tracked vehicle.After the experiment was finished,the data was read out through the upper computer.Both valid data and satisfactory results were obtained through both simulated and actual vehicle tests.
