Recent experimental findings have demonstrated the occurrence of superconductivity in Bernal bilayer graphene when induced by a magnetic field.In this study,we conduct a theoretical investigation of the potential pair...Recent experimental findings have demonstrated the occurrence of superconductivity in Bernal bilayer graphene when induced by a magnetic field.In this study,we conduct a theoretical investigation of the potential pairing symmetry within this superconducting system.By developing a theoretical model,we primarily calculate the free energy of the system with p+ip-wave parallel spin pairing,p+ip-wave anti-parallel spin pairing and d+i d-wave pairing symmetry.Our results confirm that the magnetic field is indeed essential for generating the superconductivity.We discover that the p+ip-wave parallel spin pairing leads to a lower free energy for the system.The numerical calculations of the energy band structure,zero-energy spectral function and density of states for each of the three pairing symmetries under consideration show a strong consistency with the free energy results.展开更多
Ruthenium has been hailed as a competitive alternative for platinum toward hydrogen evolution reaction(HER),a critical process in electrochemical water splitting.In this study,we successfully prepare metallic Ru nanop...Ruthenium has been hailed as a competitive alternative for platinum toward hydrogen evolution reaction(HER),a critical process in electrochemical water splitting.In this study,we successfully prepare metallic Ru nanoparticles supported on carbon paper by utilizing a novel magnetic induction heating(MIH)method.The samples are obtained within seconds,featuring a Cl-enriched surface that is unattainable via conventional thermal annealing.The best sample within the series shows a remarkable HER activity in both acidic and alkaline media with an overpotential of only-23 and-12 mV to reach the current density of 10 mA/cm^(2),highly comparable to that of the Pt/C benchmark.Theoretical studies based on density functional theory show that the excellent electrocatalytic activity is accounted by the surface metal-Cl species that facilitate charge transfer and downshift the d-band center.Results from this study highlight the unique advantages of MIH in rapid sample preparation,where residual anion ligands play a critical role in manipulating the electronic properties of the metal surfaces and the eventual electrocatalytic activity.展开更多
The motion of electron wave packets of a metal is examined classically in the presence of the magnetic field with the aim to calculate the time intervals between two states lying on the same Fermi surface. A lower lim...The motion of electron wave packets of a metal is examined classically in the presence of the magnetic field with the aim to calculate the time intervals between two states lying on the same Fermi surface. A lower limiting value of the transition time equal to about 10–18 sec is estimated as an average for the case when the states are lying on the Fermi surface having a spherical shape. Simultaneously, an upper limit for the electron circular frequency in a metal has been also derived. A formal reference of the classical transition time to the time interval entering the energy-time uncertainty relations known in quantum mechanics is obtained.展开更多
Results of magnetic field investigation in a Kaiser type caster show that magnetic induction decays rapidly on moving inward from the outer surface and is almost doubled near corner.In the presence of screenings magne...Results of magnetic field investigation in a Kaiser type caster show that magnetic induction decays rapidly on moving inward from the outer surface and is almost doubled near corner.In the presence of screenings magnetic field strength is attenuated near periphery,but it isn't influenced within the interior.The resultant electromagnetic pressure balances with static head of liquid column,i.e,the upper magnetic induction is smaller than the lower's.However»the maximum pressure moves downward about 1 cm from half height of inductor.展开更多
Although the significant roles of magnetic induction and electromagnetic radiation in the neural system have been widely studied,their influence on Parkinson’s disease(PD)has yet to be well explored.By virtue of the ...Although the significant roles of magnetic induction and electromagnetic radiation in the neural system have been widely studied,their influence on Parkinson’s disease(PD)has yet to be well explored.By virtue of the magnetic flux variable,this paper studies the transition of firing patterns induced by magnetic induction and the regulation effect of external magnetic radiation on the firing activities of the subthalamopallidal network in basal ganglia.We find:(i)The network reproduces five typical waveforms corresponding to the severity of symptoms:weak cluster,episodic,continuous cluster,episodic,and continuous wave.(ii)Magnetic induction is a double-edged sword for the treatment of PD.Although the increase of magnetic coefficient may lead the physiological firing activity to transfer to pathological firing activity,it also can regulate the pathological intensity firing activity with excessiveβ-band power transferring to the physiological firing pattern with weakβ-band power.(iii)External magnetic radiation could inhibit continuous tremulous firing andβ-band power of subthalamic nucleus(STN),which means the severity of symptoms weakened.Especially,the bi-parameter plane of the regulation region shows that a short pulse period of magnetic radiation and a medium level of pulse percentage can well regulate pathological oscillation.This work helps to understand the firing activity of the subthalamopallidal network under electromagnetic effect.It may also provide insights into the mechanisms behind the electromagnetic therapy of PD-related firing activity.展开更多
Experimentally the plateaus characteristic for the integer quantum Hall effect is obtained in vicinity of specific values of the magnetic induction. The paper demonstrates that the ratios of these induction values to ...Experimentally the plateaus characteristic for the integer quantum Hall effect is obtained in vicinity of specific values of the magnetic induction. The paper demonstrates that the ratios of these induction values to carrier concentration in the planar crystalline samples approach systematically the quanta of the magnetic flux important for the behavior of superconductors. Moreover, the same quanta can be deduced from the Landau levels theory and their application in the magnetoresistance theory gives results being in accordance with experiments. The quanta of the magnetic flux similar to those for the integer quantum Hall effect can be obtained also for the fractional quantum Hall effect. This holds on condition the experimental ratio of the magnetic flux to carrier concentration is multiplied by the filling factor of the Landau level.展开更多
Renewable power generation is a suitable technology used to deliver energy locally to customers especially in remote regions. Wind energy based on induction generator situates in a foreground position in the total ene...Renewable power generation is a suitable technology used to deliver energy locally to customers especially in remote regions. Wind energy based on induction generator situates in a foreground position in the total energy produced using renewable sources. In the last few decades, a new self- excitation generator was based on multi-stator induction strongly emerges. This article presents a systematic modelling, a detailed analysis and the performance analysis of self-excitation dual stator winding induction generator (SE-DSWIG). The modelling of the SE-DSWIG was done with taking in account the common mutual leakage inductance between stators and the magnetizing inductance, which played a principal role in the stabilization of the output voltage in the steady state. The generator feeds the end user emulated by an inductive-resistive load. In order to simulate the weather conditions’ variation, a step change of the prime mover speed was applied on the SE-DSWIG. A passive series and shunt compensator was used to mitigate the voltage sag and swell appeared in the power system due to wind variation and the lack of reactive power consumed by the inductive load.展开更多
When considering electromagnetism, the unit of the Ammeter’s measurement should be limited to its proper unit in “Watt/Volt” which is, according to physical principles, the division quotient of the measured electri...When considering electromagnetism, the unit of the Ammeter’s measurement should be limited to its proper unit in “Watt/Volt” which is, according to physical principles, the division quotient of the measured electrical power by its electrical potential. However, the Ammeter’s reading has also a traditional definition as the rate of flow of electric charges whose unit is “Ampere”. According to recent studies that define the electric charge as energy possessing an electric potential, such traditional definition is wrong as the Ammeter’s reading should, then, has the unit “Watt”. Such duality of the Ammeter’s reading is due to the wrong definition of electric charges as electrons and insertion of the “Ampere”, as a wrong unit of the flow of electric charges. This duality represents a “redundancy” in electromagnetism as the proper Ammeter’s reading, in Watt/Volt, is a unit of entropy of the flowing energy charges. Such redundancy led to further redundancies in the field of electromagnetism. In this article, it is followed the impacts of inserting the “Ampere” as illogic unit and it is derived the proper modifications of the results of replacing the “Ampere” by its logical substitute “Watt/Volt”. Such modifications lead to a robust definition of the electron as an elementary particle which has an elementary charge of energy 1.602 × 10<sup>-19</sup> Joules and has a negative electric potential of 1 Volt and to a proper definition of the protons as elementary particles which are charged by a similar charge of electron, but it has a positive potential of 1 Volt. Additionally, the electron-volt is properly defined as an elementary charge whose energy is 1.602 × 10<sup>-19</sup> Joules and whose potential is ±1 Volt. Such modifications also lead to improve the understanding of magnetic induction and modifying the equations that characterize the performance of electric machines. The truth of such innovative understandings is verified analytically and experimentally in this article.展开更多
We statistically validate the 2011-2022 earthquake prediction records of Ada, the sixth finalist of the 2nd China AETA in 2021, who made 147 earthquake predictions (including 60% of magnitude 5.5 earthquakes) with a p...We statistically validate the 2011-2022 earthquake prediction records of Ada, the sixth finalist of the 2nd China AETA in 2021, who made 147 earthquake predictions (including 60% of magnitude 5.5 earthquakes) with a prediction accuracy higher than 70% and a confidence level of 95% over a 12-year period. Since the reliable earthquake precursor signals described by Ada and the characteristics of Alfvén waves match quite well, this paper proposes a hypothesis on how earthquakes are triggered based on the Alfvén (Q G) torsional wave model of Gillette et al. When the plume of the upper mantle column intrudes into the magma and lithosphere of the soft flow layer during the exchange of hot and cold molten material masses deep inside the Earth’s interior during ascent and descent, it is possible to form body and surface plasma sheets under certain conditions to form Alfven nonlinear isolated waves, and Alfven waves often perturb the geomagnetic field, releasing huge heat and kinetic energy thus triggering earthquakes. To explain the complex phenomenon of how Ada senses Alvfen waves and how to locate epicenters, we venture to speculate that special magnetosensory cells in a few human bodies can sense earthquake precursors and attempt to hypothesize an algorithm that analyzes how the human biological nervous system encodes and decodes earthquake precursors and explains how human magnetosensory cells can solve complex problems such as predicting earthquake magnitude and locating epicenters.展开更多
Achieving efficient integration of cancer diagnosis and therapy is of great significance to human health,but the construction of a multifunctional intelligent therapy system still faces great challenges.In this study,...Achieving efficient integration of cancer diagnosis and therapy is of great significance to human health,but the construction of a multifunctional intelligent therapy system still faces great challenges.In this study,we report an integrated multifunctional nanocomposite constructed by a simple modular assembly technology.The nanocomposites are composed of three different nanomaterials:Fe_(3)O_(4),Au,and NaErF_(4):0.5%Tm@NaYF_(4)upconversion nanoparticles(UCNPs).In this design,Fe_(3)O_(4)nanoparticles have nanozyme effect of peroxidase-like activity,which can react with H_(2)O_(2)in the tumor microenvironment to generate hydroxyl radicals.Because of its magnetic properties,it can help the nanocomposites to aggregate under the induction of magnetic fields.Au nanoparticles exhibit nanozyme effect of glucose oxidase-like activity.It can catalyze the conversion of glucose to gluconic acid and H_(2)O_(2).Ingeniously,the generated H_(2)O_(2)provides a source of reactants for the reaction of the Fe_(3)O_(4)nanozyme.In addition,the photothermal effect of Au nanoparticles under 808 nm irradiation further enhanced the nanozyme activity of Fe_(3)O_(4)and Au nanoparticles.Besides,UCNPs can emit near-infrared(NIR)-II fluorescence under 808 nm irradiation,which can provide imaging-guided during cancer treatment.Then,the nanocomposites were further modified by poly(vinylpyrrolidone)(PVP)to obtain UCNPs/Au/Fe_(3)O_(4)-PVP with good biocompatibility and high-efficiency cancer treatment ability.展开更多
Magnetoacoustic tomography with magnetic induction(MAT-MI),as a new kind of in-vivo imaging method,has potential application value in interstitial fluid research.In this paper,we propose the application of MAT-MI with...Magnetoacoustic tomography with magnetic induction(MAT-MI),as a new kind of in-vivo imaging method,has potential application value in interstitial fluid research.In this paper,we propose the application of MAT-MI with liquid metal serving as a tracer of the interstitial structure to study its fluid behavior,and use it to implement the positional imaging of the spatial distribution of liquid metal.Owing to the particularity of liquid metal magnetoacoustic pressure(MAP)signals,we propose an envelope analysis method to extract the rising edge of the amplitude envelope of the detected waveform as effective position data.And for the first time,we propose the method of superpositing pixel matrix to achieve the position imaging of liquid metal.Finally,the positional imaging of the liquid metal sample embedded in the gel is achieved to have relatively accurate results.This study provides a method of effectively extracting data and implementing the position imaging for liquid metal in the interstitial structure in the frame of MAT-MI.展开更多
In the non-conventional media like underwater and underground,the Radio Frequency(RF)communication technique does not perform well due to large antenna size requirement and high path loss.In such media,magnetic induct...In the non-conventional media like underwater and underground,the Radio Frequency(RF)communication technique does not perform well due to large antenna size requirement and high path loss.In such media,magnetic induction(MI)communication technique is very promising due to small coil size and constant channel behavior.Unlike the RF technique,the communication range in MI technique is relatively less.To enhance this range,a waveguide technique is already brought in practice.This technique employs single layer coils to enhance the performance of MI waveguide.To further enhance the system functioning,in this paper,we investigated the performance of multi-layer coil(MLC)antenna based MI waveguide communication system in terms of transmission range,path loss,bit error rate(BER)and bandwidth.Besides,the system performance is quantitatively evaluated in three different non-conventional media viz.,dry soil,fresh water and wet soil.As compared with the single layer counterpart,the MLC system shows a significant improvement in transmission range,BER even in loosely coupled scenarios and shows a corresponding reduction in path loss.However,the bandwidth is observed to be low(<1 KHz).In this analysis,the eddy current effects and parasitic capacitance are compared for single and multilayer coils.It is observed that the proposed system performs better in dry soil medium due to less medium conductivity.展开更多
Liquid polymers(LP)have become an important structural material used in the construction industry in the last decade.This paper investigates the viability of using commercially available LPs as a coating materia...Liquid polymers(LP)have become an important structural material used in the construction industry in the last decade.This paper investigates the viability of using commercially available LPs as a coating material to improve the flexural strength of fiber-modified concrete beams.The scope included preparing rectangular prism concrete beams with a concrete mixture including fly ash and fiber and coating them with four different liquid polymers at a uniform thickness following the curing process while one set of samples was maintained under the same conditions as a control group without coating.In addition,cylindrical samples were prepared to determine the compressive strength of the concrete mixture.Following the curing process in an unconfined open-air laboratory environment for another 28 days,concrete samples were tested to determine the flexural strength and deflection characteristics under center point loading equipment.The results revealed that all four coating types enhanced both the flexural strength and the average maximum deflection of the beams compared to the control group.While the enhancement in the flexural strength changed approximately between 5%and 36%depending on the coating type,the improvements in average maximum deflections varied between 3.7%and 28.4%.展开更多
The grounding grid buried in the earth will become a hidden danger to the safety of substations due to some faults of breaks or thinner conductors in corrosion.A novel method to get accurate status of grounding grid w...The grounding grid buried in the earth will become a hidden danger to the safety of substations due to some faults of breaks or thinner conductors in corrosion.A novel method to get accurate status of grounding grid was proposed based on measuring magnetic induction intensity.The basic structure of grounding grid without working drawing was concluded,and the positions and the status of faults were diagnosed by this method.The completed detecting system,including hardware device of data measurement,diagnosis,and analysis software,was introduced concisely.The results of simulations and applications show that this method is simple and effective in the practical engineering.展开更多
In this study,magnetomechanical coupling tests were performed on Q235 solid round steel model specimens in NIM-200HF magnetomechanical coupling equipment.Hysteresis loops were obtained in different magnetic fields and...In this study,magnetomechanical coupling tests were performed on Q235 solid round steel model specimens in NIM-200HF magnetomechanical coupling equipment.Hysteresis loops were obtained in different magnetic fields and stresses.Magnetization curves were also achieved at different stresses.Influence of the applied stresses on the hysteresis loops was investigated.The stress sensitive region and linear stress sensitive region of magnetic induction were determined for the model specimen according to the experimental data.The dependence relation of magnetic induction versus applied stresses was established,and the optimum magnetic field was determined in the stress sensitive range of magnetic induction,which builds a basis for nondestructive testing(NDT) of stress with the total magnetic flux for steel structure.Based on modified Jiles-Atherton's model of magnetic hysteresis,the hysteresis loop for Q235 steel 4-mm diameter model specimen was numerically simulated,which was well consistent with the experimental results.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No.12074130)the Natural Science Foundation of Guangdong Province (Grant No.2021A1515012340)。
文摘Recent experimental findings have demonstrated the occurrence of superconductivity in Bernal bilayer graphene when induced by a magnetic field.In this study,we conduct a theoretical investigation of the potential pairing symmetry within this superconducting system.By developing a theoretical model,we primarily calculate the free energy of the system with p+ip-wave parallel spin pairing,p+ip-wave anti-parallel spin pairing and d+i d-wave pairing symmetry.Our results confirm that the magnetic field is indeed essential for generating the superconductivity.We discover that the p+ip-wave parallel spin pairing leads to a lower free energy for the system.The numerical calculations of the energy band structure,zero-energy spectral function and density of states for each of the three pairing symmetries under consideration show a strong consistency with the free energy results.
基金National Science Foundation,Grant/Award Numbers:CHE-1900235,CHE-2003685Office of Science,Office of Basic Energy Sciences,of the U.S.Department of Energy,Grant/Award Number:DE-AC02-05CH11231+3 种基金U.S.Department of Energy,Office of Science,Office of Basic Energy Sciences,Grant/Award Number:DE-AC02-76SF00515NSF MRI program,Grant/Award Number:AST-1828315Grant-in-Aid of Research,Grant/Award Number:G20211001-639National Academy of Sciences,administered by Sigma Xi,The Scientific Research Society。
文摘Ruthenium has been hailed as a competitive alternative for platinum toward hydrogen evolution reaction(HER),a critical process in electrochemical water splitting.In this study,we successfully prepare metallic Ru nanoparticles supported on carbon paper by utilizing a novel magnetic induction heating(MIH)method.The samples are obtained within seconds,featuring a Cl-enriched surface that is unattainable via conventional thermal annealing.The best sample within the series shows a remarkable HER activity in both acidic and alkaline media with an overpotential of only-23 and-12 mV to reach the current density of 10 mA/cm^(2),highly comparable to that of the Pt/C benchmark.Theoretical studies based on density functional theory show that the excellent electrocatalytic activity is accounted by the surface metal-Cl species that facilitate charge transfer and downshift the d-band center.Results from this study highlight the unique advantages of MIH in rapid sample preparation,where residual anion ligands play a critical role in manipulating the electronic properties of the metal surfaces and the eventual electrocatalytic activity.
文摘The motion of electron wave packets of a metal is examined classically in the presence of the magnetic field with the aim to calculate the time intervals between two states lying on the same Fermi surface. A lower limiting value of the transition time equal to about 10–18 sec is estimated as an average for the case when the states are lying on the Fermi surface having a spherical shape. Simultaneously, an upper limit for the electron circular frequency in a metal has been also derived. A formal reference of the classical transition time to the time interval entering the energy-time uncertainty relations known in quantum mechanics is obtained.
基金Supported by the National Doctoral Program Fund of the State Education Committee of Chinathe key program of the 8th Five-Year Plan of Chinathe Natural Science Foundation of Liaoning Province。
文摘Results of magnetic field investigation in a Kaiser type caster show that magnetic induction decays rapidly on moving inward from the outer surface and is almost doubled near corner.In the presence of screenings magnetic field strength is attenuated near periphery,but it isn't influenced within the interior.The resultant electromagnetic pressure balances with static head of liquid column,i.e,the upper magnetic induction is smaller than the lower's.However»the maximum pressure moves downward about 1 cm from half height of inductor.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11972292,12172291,and 12072265)the 111 Project(Grant No.BP0719007)。
文摘Although the significant roles of magnetic induction and electromagnetic radiation in the neural system have been widely studied,their influence on Parkinson’s disease(PD)has yet to be well explored.By virtue of the magnetic flux variable,this paper studies the transition of firing patterns induced by magnetic induction and the regulation effect of external magnetic radiation on the firing activities of the subthalamopallidal network in basal ganglia.We find:(i)The network reproduces five typical waveforms corresponding to the severity of symptoms:weak cluster,episodic,continuous cluster,episodic,and continuous wave.(ii)Magnetic induction is a double-edged sword for the treatment of PD.Although the increase of magnetic coefficient may lead the physiological firing activity to transfer to pathological firing activity,it also can regulate the pathological intensity firing activity with excessiveβ-band power transferring to the physiological firing pattern with weakβ-band power.(iii)External magnetic radiation could inhibit continuous tremulous firing andβ-band power of subthalamic nucleus(STN),which means the severity of symptoms weakened.Especially,the bi-parameter plane of the regulation region shows that a short pulse period of magnetic radiation and a medium level of pulse percentage can well regulate pathological oscillation.This work helps to understand the firing activity of the subthalamopallidal network under electromagnetic effect.It may also provide insights into the mechanisms behind the electromagnetic therapy of PD-related firing activity.
文摘Experimentally the plateaus characteristic for the integer quantum Hall effect is obtained in vicinity of specific values of the magnetic induction. The paper demonstrates that the ratios of these induction values to carrier concentration in the planar crystalline samples approach systematically the quanta of the magnetic flux important for the behavior of superconductors. Moreover, the same quanta can be deduced from the Landau levels theory and their application in the magnetoresistance theory gives results being in accordance with experiments. The quanta of the magnetic flux similar to those for the integer quantum Hall effect can be obtained also for the fractional quantum Hall effect. This holds on condition the experimental ratio of the magnetic flux to carrier concentration is multiplied by the filling factor of the Landau level.
文摘Renewable power generation is a suitable technology used to deliver energy locally to customers especially in remote regions. Wind energy based on induction generator situates in a foreground position in the total energy produced using renewable sources. In the last few decades, a new self- excitation generator was based on multi-stator induction strongly emerges. This article presents a systematic modelling, a detailed analysis and the performance analysis of self-excitation dual stator winding induction generator (SE-DSWIG). The modelling of the SE-DSWIG was done with taking in account the common mutual leakage inductance between stators and the magnetizing inductance, which played a principal role in the stabilization of the output voltage in the steady state. The generator feeds the end user emulated by an inductive-resistive load. In order to simulate the weather conditions’ variation, a step change of the prime mover speed was applied on the SE-DSWIG. A passive series and shunt compensator was used to mitigate the voltage sag and swell appeared in the power system due to wind variation and the lack of reactive power consumed by the inductive load.
文摘When considering electromagnetism, the unit of the Ammeter’s measurement should be limited to its proper unit in “Watt/Volt” which is, according to physical principles, the division quotient of the measured electrical power by its electrical potential. However, the Ammeter’s reading has also a traditional definition as the rate of flow of electric charges whose unit is “Ampere”. According to recent studies that define the electric charge as energy possessing an electric potential, such traditional definition is wrong as the Ammeter’s reading should, then, has the unit “Watt”. Such duality of the Ammeter’s reading is due to the wrong definition of electric charges as electrons and insertion of the “Ampere”, as a wrong unit of the flow of electric charges. This duality represents a “redundancy” in electromagnetism as the proper Ammeter’s reading, in Watt/Volt, is a unit of entropy of the flowing energy charges. Such redundancy led to further redundancies in the field of electromagnetism. In this article, it is followed the impacts of inserting the “Ampere” as illogic unit and it is derived the proper modifications of the results of replacing the “Ampere” by its logical substitute “Watt/Volt”. Such modifications lead to a robust definition of the electron as an elementary particle which has an elementary charge of energy 1.602 × 10<sup>-19</sup> Joules and has a negative electric potential of 1 Volt and to a proper definition of the protons as elementary particles which are charged by a similar charge of electron, but it has a positive potential of 1 Volt. Additionally, the electron-volt is properly defined as an elementary charge whose energy is 1.602 × 10<sup>-19</sup> Joules and whose potential is ±1 Volt. Such modifications also lead to improve the understanding of magnetic induction and modifying the equations that characterize the performance of electric machines. The truth of such innovative understandings is verified analytically and experimentally in this article.
文摘We statistically validate the 2011-2022 earthquake prediction records of Ada, the sixth finalist of the 2nd China AETA in 2021, who made 147 earthquake predictions (including 60% of magnitude 5.5 earthquakes) with a prediction accuracy higher than 70% and a confidence level of 95% over a 12-year period. Since the reliable earthquake precursor signals described by Ada and the characteristics of Alfvén waves match quite well, this paper proposes a hypothesis on how earthquakes are triggered based on the Alfvén (Q G) torsional wave model of Gillette et al. When the plume of the upper mantle column intrudes into the magma and lithosphere of the soft flow layer during the exchange of hot and cold molten material masses deep inside the Earth’s interior during ascent and descent, it is possible to form body and surface plasma sheets under certain conditions to form Alfven nonlinear isolated waves, and Alfven waves often perturb the geomagnetic field, releasing huge heat and kinetic energy thus triggering earthquakes. To explain the complex phenomenon of how Ada senses Alvfen waves and how to locate epicenters, we venture to speculate that special magnetosensory cells in a few human bodies can sense earthquake precursors and attempt to hypothesize an algorithm that analyzes how the human biological nervous system encodes and decodes earthquake precursors and explains how human magnetosensory cells can solve complex problems such as predicting earthquake magnitude and locating epicenters.
基金This work was supported by the financial aid from the National Natural Science Foundation of China(Nos.22020102003,21834007,and 52103276)the National Key R&D Program of China(No.2020YFA0712102)+2 种基金the Program of Science and Technology Development Plan of Jilin Province of China(No.20220508076RC)the Natural Science Foundation of Guangdong Province of China(No.2022A1515010947)Guangzhou Basic and Applied Basic Research Foundation(No.202201011343).
文摘Achieving efficient integration of cancer diagnosis and therapy is of great significance to human health,but the construction of a multifunctional intelligent therapy system still faces great challenges.In this study,we report an integrated multifunctional nanocomposite constructed by a simple modular assembly technology.The nanocomposites are composed of three different nanomaterials:Fe_(3)O_(4),Au,and NaErF_(4):0.5%Tm@NaYF_(4)upconversion nanoparticles(UCNPs).In this design,Fe_(3)O_(4)nanoparticles have nanozyme effect of peroxidase-like activity,which can react with H_(2)O_(2)in the tumor microenvironment to generate hydroxyl radicals.Because of its magnetic properties,it can help the nanocomposites to aggregate under the induction of magnetic fields.Au nanoparticles exhibit nanozyme effect of glucose oxidase-like activity.It can catalyze the conversion of glucose to gluconic acid and H_(2)O_(2).Ingeniously,the generated H_(2)O_(2)provides a source of reactants for the reaction of the Fe_(3)O_(4)nanozyme.In addition,the photothermal effect of Au nanoparticles under 808 nm irradiation further enhanced the nanozyme activity of Fe_(3)O_(4)and Au nanoparticles.Besides,UCNPs can emit near-infrared(NIR)-II fluorescence under 808 nm irradiation,which can provide imaging-guided during cancer treatment.Then,the nanocomposites were further modified by poly(vinylpyrrolidone)(PVP)to obtain UCNPs/Au/Fe_(3)O_(4)-PVP with good biocompatibility and high-efficiency cancer treatment ability.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61771448,61427806,and 51937010)the National Key Research and Development Program of China(Grant No.2018YFC0115200)the Natural Science Fund from the Chinese Academy of Sciences(Grant Nos.ZDKYYQ20190002 and YJKYYQ20190005)。
文摘Magnetoacoustic tomography with magnetic induction(MAT-MI),as a new kind of in-vivo imaging method,has potential application value in interstitial fluid research.In this paper,we propose the application of MAT-MI with liquid metal serving as a tracer of the interstitial structure to study its fluid behavior,and use it to implement the positional imaging of the spatial distribution of liquid metal.Owing to the particularity of liquid metal magnetoacoustic pressure(MAP)signals,we propose an envelope analysis method to extract the rising edge of the amplitude envelope of the detected waveform as effective position data.And for the first time,we propose the method of superpositing pixel matrix to achieve the position imaging of liquid metal.Finally,the positional imaging of the liquid metal sample embedded in the gel is achieved to have relatively accurate results.This study provides a method of effectively extracting data and implementing the position imaging for liquid metal in the interstitial structure in the frame of MAT-MI.
文摘In the non-conventional media like underwater and underground,the Radio Frequency(RF)communication technique does not perform well due to large antenna size requirement and high path loss.In such media,magnetic induction(MI)communication technique is very promising due to small coil size and constant channel behavior.Unlike the RF technique,the communication range in MI technique is relatively less.To enhance this range,a waveguide technique is already brought in practice.This technique employs single layer coils to enhance the performance of MI waveguide.To further enhance the system functioning,in this paper,we investigated the performance of multi-layer coil(MLC)antenna based MI waveguide communication system in terms of transmission range,path loss,bit error rate(BER)and bandwidth.Besides,the system performance is quantitatively evaluated in three different non-conventional media viz.,dry soil,fresh water and wet soil.As compared with the single layer counterpart,the MLC system shows a significant improvement in transmission range,BER even in loosely coupled scenarios and shows a corresponding reduction in path loss.However,the bandwidth is observed to be low(<1 KHz).In this analysis,the eddy current effects and parasitic capacitance are compared for single and multilayer coils.It is observed that the proposed system performs better in dry soil medium due to less medium conductivity.
文摘Liquid polymers(LP)have become an important structural material used in the construction industry in the last decade.This paper investigates the viability of using commercially available LPs as a coating material to improve the flexural strength of fiber-modified concrete beams.The scope included preparing rectangular prism concrete beams with a concrete mixture including fly ash and fiber and coating them with four different liquid polymers at a uniform thickness following the curing process while one set of samples was maintained under the same conditions as a control group without coating.In addition,cylindrical samples were prepared to determine the compressive strength of the concrete mixture.Following the curing process in an unconfined open-air laboratory environment for another 28 days,concrete samples were tested to determine the flexural strength and deflection characteristics under center point loading equipment.The results revealed that all four coating types enhanced both the flexural strength and the average maximum deflection of the beams compared to the control group.While the enhancement in the flexural strength changed approximately between 5%and 36%depending on the coating type,the improvements in average maximum deflections varied between 3.7%and 28.4%.
基金This work was supported in part by the Scientific Research Foundation of Doctor Degree in North China Electric Power University(200912008).
文摘The grounding grid buried in the earth will become a hidden danger to the safety of substations due to some faults of breaks or thinner conductors in corrosion.A novel method to get accurate status of grounding grid was proposed based on measuring magnetic induction intensity.The basic structure of grounding grid without working drawing was concluded,and the positions and the status of faults were diagnosed by this method.The completed detecting system,including hardware device of data measurement,diagnosis,and analysis software,was introduced concisely.The results of simulations and applications show that this method is simple and effective in the practical engineering.
基金financially supported by the Natural Science Foundation of Jiangsu Province(BK20211243)Jiangsu Provincial Key Research and Development Program(BE2022708)+1 种基金the Tribology Science Fund of State Key Laboratory of Tribology in Advanced Equipment(SKLTKF21B15)the Open Fund of State Key Laboratory of Solid Lubrication,Lanzhou Institute of Chemical Physics(LSL-2107).
基金the National Natural Science Foundation of China(Nos.51108035,51178388 and 10972168)the Natural Science Basic Research Plan in Shaanxi Province of China(No.2010JQ7006)+1 种基金the China Postdoctoral Science Foundation(No.20100481313)the Special Fund for Basic Scientific Research of Central College of China(No.CHD2012ZD012)
文摘In this study,magnetomechanical coupling tests were performed on Q235 solid round steel model specimens in NIM-200HF magnetomechanical coupling equipment.Hysteresis loops were obtained in different magnetic fields and stresses.Magnetization curves were also achieved at different stresses.Influence of the applied stresses on the hysteresis loops was investigated.The stress sensitive region and linear stress sensitive region of magnetic induction were determined for the model specimen according to the experimental data.The dependence relation of magnetic induction versus applied stresses was established,and the optimum magnetic field was determined in the stress sensitive range of magnetic induction,which builds a basis for nondestructive testing(NDT) of stress with the total magnetic flux for steel structure.Based on modified Jiles-Atherton's model of magnetic hysteresis,the hysteresis loop for Q235 steel 4-mm diameter model specimen was numerically simulated,which was well consistent with the experimental results.
