We presented the first photometric light curve solutions of four W Ursae Majoris-type contact binary systems.This investigation utilized photometric data from the Transiting Exoplanet Survey Satellite and Gaia Data Re...We presented the first photometric light curve solutions of four W Ursae Majoris-type contact binary systems.This investigation utilized photometric data from the Transiting Exoplanet Survey Satellite and Gaia Data Release 3(DR3).We used the PHysics Of Eclipsing BinariEs Python code and the Markov Chain Monte Carlo method for these light curve solutions.Only TIC 249064185 among the target systems needed a cold starspot to be included in the analysis.Based on the estimated mass ratios for these total eclipse systems,three of them are categorized as low mass ratio contact binary stars.The absolute parameters of the systems were estimated using the Gaia DR3 parallax method and the orbital period and semimajor axis(P-a)empirical relationship.We ascertained that the TIC 318015356 and TIC 55522736 systems are A-subtypes,while TIC 249064185 and TIC 397984843 are W-subtypes,depending on each component’s effective temperature and mass.We estimated the initial masses of the stars,the mass lost by the binary system,and the systems’ages.We displayed star positions in the mass-radius,mass-luminosity,and total mass-orbital angular momentum diagrams.In addition,our findings indicate a good agreement with the mass-temperature empirical parameter relationship for the primary stars.展开更多
The low-energy muon facility at PSI provides nearly fully polarized positive muons with tunable energies in the ke V range to carry out muon spin rotation(LE-μSR)experiments with nanometer depth resolution on thin fi...The low-energy muon facility at PSI provides nearly fully polarized positive muons with tunable energies in the ke V range to carry out muon spin rotation(LE-μSR)experiments with nanometer depth resolution on thin films,heterostructures, and near-surface regions. The low-energy muon beam is focused and transported to the sample by electrostatic lenses. In order to achieve a minimum beam spot size at the sample position and to enable the steering of the beam in the horizontal and vertical direction, a special electrostatic device has been implemented close to the sample position. It consists of a cylinder at ground potential followed by four conically shaped electrodes,which can be operated at different electric potential. In LE-μSR experiments, an electric field at the sample along the beam direction can be applied to accelerate/decelerate muons to different energies(0.5–30 keV). Additionally, a horizontal or vertical magnetic field can be superimposed for transverse or longitudinal field μSR experiments. The focusing properties of the conical lens in the presence of these additional electric and magnetic fields have been investigated and optimized by Geant4 simulations. Some experimental tests were also performed and show that the simulation well describes the experimental setup.展开更多
Paul Scherrer Institut hosts the Proton Irradiation Facility used for radiation effects studies and exposure tests in preparation of satellite missions for the European Space Agency. The facility allows for realistic ...Paul Scherrer Institut hosts the Proton Irradiation Facility used for radiation effects studies and exposure tests in preparation of satellite missions for the European Space Agency. The facility allows for realistic simulation of the space proton spectra in the energy range from 6 MeV up to 230 MeV with exposure fluxes ranging from very low up to as high as 109 p/cm2/sec. Recently, approved ESA mission to Jupiter—JUICE—also brought a need for tests with high energy electron beams. For this purpose, another facility was established in the PSI secondary beam area piM1. Secondary particles are produced on the thick carbon target hit by energetic proton beam. Dedicated beam optics enables selection of the particle charge and momentum and guides them to the tests area. Characterization of electron beams at various momenta was performed with respect to their intensity, profiles and contamination by pions and muons. Electron fluxes ranging from 1.5 × 103/cm2/s at 20 MeV/c to 2.3 × 106/cm2/s at 345 MeV/c with gaussian beam profiles with FWHM of about 4 cm were measured. Beam contamination with heavier particles becomes negligible for all momenta lower than 115 MeV/c. This allows for using them for components and shielding characterization and detector calibration experiments. Several such experiments have been already performed utilizing available beam time of few weeks per year.展开更多
Electrochemical impedance spectroscopy(EIS)is a widely used technique to monitor the electrical properties of a catalyst under electrocatalytic conditions.Although it is extensively used for research in electrocatalys...Electrochemical impedance spectroscopy(EIS)is a widely used technique to monitor the electrical properties of a catalyst under electrocatalytic conditions.Although it is extensively used for research in electrocatalysis,its effectiveness and power have not been fully harnessed to elucidate complex interfacial processes.Herein,we use the frequency dispersion parameter,n,which is extracted from EIS measurements(C_(s)=af^(n+1),-2<n<-1),to describe the dispersion characteristics of capacitance and interfacial properties of Co_(3)O_(4) before the onset of oxygen evolution reaction(OER)in alkaline conditions.We first prove that the n-value is sensitive to the interfacial electronic changes associated with Co redox processes and surface reconstruction.The n-value decreases by increasing the specific/active surface area of the catalysts.We further modify the interfacial properties by changing different components,i.e.,replacing the proton with deuterium,adding ethanol as a new oxidant,and changing the cation in the electrolyte.Intriguingly,the n-value can identify different influences on the interfacial process of proton transfer,the decrease and blocking of oxidized Co species,and the interfacial water structure.We demonstrate that the n-value extracted from EIS measurements is sensitive to the kinetic isotope effect,electrolyte cation,adsorbate surface coverage of oxidized Co species,and the interfacial water structure.Thus,it can be helpful to differentiate the multiple factors affecting the catalyst interface.These findings convey that the frequency dispersion of capacitance is a convenient and useful method to uncover the interfacial properties under electrocatalytic conditions,which helps to advance the understanding of the interfaceactivity relationship.展开更多
The advent of artificial intelligence(AI)in recent years has brought about transformative changes across various sectors,including healthcare.In nursing practice,education,and research,AI has the potential to revoluti...The advent of artificial intelligence(AI)in recent years has brought about transformative changes across various sectors,including healthcare.In nursing practice,education,and research,AI has the potential to revolutionize traditional methodologies,enhance learning experiences,and improve patient outcomes.Integrating AI tools and techniques can provide clinicians with smarter clinical solutions and nursing students with more robust and interactive learning environments,while also advancing research capabilities in the field.Despite the promising prospects,the incorporation of AI into nursing practice,education,and research presents several challenges.Firstly,there is a concern about the potential displacement of human roles in nursing due to automation,which may affect the human-centric nature of nursing care.Secondly,there are issues related to the lag in AI competency among nurses.Many current nursing curricula do not include comprehensive AI training,leading to a lack of preparedness in utilizing these technologies effectively.Lastly,the ethical implications of AI in healthcare,such as data privacy,patient consent,and the potential for biased algorithms,need to be meticulously addressed.To harness the full potential of AI in nursing practice,education,and research,several strategic actions including reinvesting in humanistic practice,revising core competencies and curriculum,and developing new ethical guidelines.展开更多
In this work,Ga-doped Ce RhIn_(5) single crystals are grown by In/Ga flux method.Single-crystal X-ray diffraction,magnetic susceptibility,specific heat,and neutron diffraction measurements are utilized to characterize...In this work,Ga-doped Ce RhIn_(5) single crystals are grown by In/Ga flux method.Single-crystal X-ray diffraction,magnetic susceptibility,specific heat,and neutron diffraction measurements are utilized to characterize the sample quality and the antiferromagnetic transition temperature T_(N).By substituting In with Ga,T_(N) is slightly decreased,but the antiferromagnetic transition peaks in magnetic susceptibility and specific heat measurements are obviously broadened by external field along c-axis.By comparing with Zn-doped Ce RhIn_(5),it can be concluded that T_(N) is dominated by electron density,and the stiffness of antiferromagnetic transition is obviously reduced by Ga substitution.The substitution effects of Ga are possibly caused by forming heterogeneous local structures,which avoids quantum critical point,superconductivity,and non-Fermi liquid states.Investigations on Gadoped Ce RhIn_(5) help to comprehend the chemical substitution effects in Ce RhIn_(5),and the interaction between heterogeneous structure and long-range antiferromagnetic states.展开更多
The all-vanadium redox flow battery(VRFB)plays an important role in the energy transition toward renewable technologies by providing grid-scale energy storage.Their deployment,however,is limited by the lack of membran...The all-vanadium redox flow battery(VRFB)plays an important role in the energy transition toward renewable technologies by providing grid-scale energy storage.Their deployment,however,is limited by the lack of membranes that provide both a high energy efficiency and capacity retention.Typically,the improvement of the battery’s energy efficiency comes at the cost of its capacity retention.Herein,novel N-alkylated and N-benzylated meta-polybenzimidazole(m-PBI)membranes are used to understand the molecular requirements of the polymer electrolyte in a vanadium redox flow battery,providing an important toolbox for future research toward next-generation membrane materials in energy storage devices.The addition of an ethyl side chain to the m-PBI backbone increases its affinity toward the acidic electrolyte,thereby increasing its ionic conductivity and the corresponding energy efficiency of the VRFB cell from 70%to 78%at a current density of 200 mA cm^(-2).In addition,cells equipped with ethylated m-PBI showed better capacity retention than their pristine counterpart,respectively 91%versus 87%,over 200 cycles at 200 mA cm^(-2).The outstanding VRFB cycling performance,together with the low-cost and fluorine-free chemistry of the N-alkylated m-PBI polymer,makes this material a promising membrane to be used in next-generation VRFB systems.展开更多
Elucidating the relationship between spin excitations and fermiology is essential for clarifying the pairing mechanism in iron-based superconductors(FeSCs).Here,we report inelastic neutron scattering results on the ho...Elucidating the relationship between spin excitations and fermiology is essential for clarifying the pairing mechanism in iron-based superconductors(FeSCs).Here,we report inelastic neutron scattering results on the hole overdoped Ba_(0.4)K_(0.6)Fe_(2)As_(2) near a Lifshitz transition,where the electron pocket at M point is nearly replaced by four hole pockets.In the normal state,the spin excitations is observed at incommensurate wave vectors with a chimney-like dispersion.By cooling down to the superconducting state,a neutron spin resonance mode emerges with a peak energy of Er=14-15 meV,weakly modulated along the L-direction.The incommensurability notably increases at low energies,giving rise to downward dispersions of the resonance mode.This behavior contrasts sharply with the upward dispersions of resonance observed in optimally doped Ba_(0.67)K_(0.33)Fe_(2)As_(2) contributed by the hole to electron scattering,but resembles those in KFe_(2)As_(2) and KCa_(2)Fe_(4)As_(4)F_(2) where the fermiology is dominated by hole pockets.These results highlight the critical role of electronic structure modifications near the Fermi level,especially in governing interband scattering under imperfect nesting conditions,which fundamentally shape the spin dynamics of FeSCs.展开更多
基金founded by the Gordon and Betty Moore Foundation through grants GBMF5490 and GBMF10501 to Ohio State Universitythe Alfred P.Sloan Foundation grant G-2021-14192
文摘We presented the first photometric light curve solutions of four W Ursae Majoris-type contact binary systems.This investigation utilized photometric data from the Transiting Exoplanet Survey Satellite and Gaia Data Release 3(DR3).We used the PHysics Of Eclipsing BinariEs Python code and the Markov Chain Monte Carlo method for these light curve solutions.Only TIC 249064185 among the target systems needed a cold starspot to be included in the analysis.Based on the estimated mass ratios for these total eclipse systems,three of them are categorized as low mass ratio contact binary stars.The absolute parameters of the systems were estimated using the Gaia DR3 parallax method and the orbital period and semimajor axis(P-a)empirical relationship.We ascertained that the TIC 318015356 and TIC 55522736 systems are A-subtypes,while TIC 249064185 and TIC 397984843 are W-subtypes,depending on each component’s effective temperature and mass.We estimated the initial masses of the stars,the mass lost by the binary system,and the systems’ages.We displayed star positions in the mass-radius,mass-luminosity,and total mass-orbital angular momentum diagrams.In addition,our findings indicate a good agreement with the mass-temperature empirical parameter relationship for the primary stars.
基金a scholarship from the China Scholarship Council (CSC)financial support from PSI for her stay at PSI
文摘The low-energy muon facility at PSI provides nearly fully polarized positive muons with tunable energies in the ke V range to carry out muon spin rotation(LE-μSR)experiments with nanometer depth resolution on thin films,heterostructures, and near-surface regions. The low-energy muon beam is focused and transported to the sample by electrostatic lenses. In order to achieve a minimum beam spot size at the sample position and to enable the steering of the beam in the horizontal and vertical direction, a special electrostatic device has been implemented close to the sample position. It consists of a cylinder at ground potential followed by four conically shaped electrodes,which can be operated at different electric potential. In LE-μSR experiments, an electric field at the sample along the beam direction can be applied to accelerate/decelerate muons to different energies(0.5–30 keV). Additionally, a horizontal or vertical magnetic field can be superimposed for transverse or longitudinal field μSR experiments. The focusing properties of the conical lens in the presence of these additional electric and magnetic fields have been investigated and optimized by Geant4 simulations. Some experimental tests were also performed and show that the simulation well describes the experimental setup.
文摘Paul Scherrer Institut hosts the Proton Irradiation Facility used for radiation effects studies and exposure tests in preparation of satellite missions for the European Space Agency. The facility allows for realistic simulation of the space proton spectra in the energy range from 6 MeV up to 230 MeV with exposure fluxes ranging from very low up to as high as 109 p/cm2/sec. Recently, approved ESA mission to Jupiter—JUICE—also brought a need for tests with high energy electron beams. For this purpose, another facility was established in the PSI secondary beam area piM1. Secondary particles are produced on the thick carbon target hit by energetic proton beam. Dedicated beam optics enables selection of the particle charge and momentum and guides them to the tests area. Characterization of electron beams at various momenta was performed with respect to their intensity, profiles and contamination by pions and muons. Electron fluxes ranging from 1.5 × 103/cm2/s at 20 MeV/c to 2.3 × 106/cm2/s at 345 MeV/c with gaussian beam profiles with FWHM of about 4 cm were measured. Beam contamination with heavier particles becomes negligible for all momenta lower than 115 MeV/c. This allows for using them for components and shielding characterization and detector calibration experiments. Several such experiments have been already performed utilizing available beam time of few weeks per year.
基金Swiss National Science Foundation through its PRIM A grant(grant No.PR00P2_193111)the NCCR MARVEL,a National Centre of Competence in Researchfunded by the Swiss National Science Foundation。
文摘Electrochemical impedance spectroscopy(EIS)is a widely used technique to monitor the electrical properties of a catalyst under electrocatalytic conditions.Although it is extensively used for research in electrocatalysis,its effectiveness and power have not been fully harnessed to elucidate complex interfacial processes.Herein,we use the frequency dispersion parameter,n,which is extracted from EIS measurements(C_(s)=af^(n+1),-2<n<-1),to describe the dispersion characteristics of capacitance and interfacial properties of Co_(3)O_(4) before the onset of oxygen evolution reaction(OER)in alkaline conditions.We first prove that the n-value is sensitive to the interfacial electronic changes associated with Co redox processes and surface reconstruction.The n-value decreases by increasing the specific/active surface area of the catalysts.We further modify the interfacial properties by changing different components,i.e.,replacing the proton with deuterium,adding ethanol as a new oxidant,and changing the cation in the electrolyte.Intriguingly,the n-value can identify different influences on the interfacial process of proton transfer,the decrease and blocking of oxidized Co species,and the interfacial water structure.We demonstrate that the n-value extracted from EIS measurements is sensitive to the kinetic isotope effect,electrolyte cation,adsorbate surface coverage of oxidized Co species,and the interfacial water structure.Thus,it can be helpful to differentiate the multiple factors affecting the catalyst interface.These findings convey that the frequency dispersion of capacitance is a convenient and useful method to uncover the interfacial properties under electrocatalytic conditions,which helps to advance the understanding of the interfaceactivity relationship.
文摘The advent of artificial intelligence(AI)in recent years has brought about transformative changes across various sectors,including healthcare.In nursing practice,education,and research,AI has the potential to revolutionize traditional methodologies,enhance learning experiences,and improve patient outcomes.Integrating AI tools and techniques can provide clinicians with smarter clinical solutions and nursing students with more robust and interactive learning environments,while also advancing research capabilities in the field.Despite the promising prospects,the incorporation of AI into nursing practice,education,and research presents several challenges.Firstly,there is a concern about the potential displacement of human roles in nursing due to automation,which may affect the human-centric nature of nursing care.Secondly,there are issues related to the lag in AI competency among nurses.Many current nursing curricula do not include comprehensive AI training,leading to a lack of preparedness in utilizing these technologies effectively.Lastly,the ethical implications of AI in healthcare,such as data privacy,patient consent,and the potential for biased algorithms,need to be meticulously addressed.To harness the full potential of AI in nursing practice,education,and research,several strategic actions including reinvesting in humanistic practice,revising core competencies and curriculum,and developing new ethical guidelines.
基金supported by the National Key Research and Development Program of China(Grant No.2022YFA1402203)the National Natural Science Foundations of China(Grant Nos.12174065 and 12104424)the Shanghai Municipal Science and Technology(Grant No.2019SHZDZX01)。
文摘In this work,Ga-doped Ce RhIn_(5) single crystals are grown by In/Ga flux method.Single-crystal X-ray diffraction,magnetic susceptibility,specific heat,and neutron diffraction measurements are utilized to characterize the sample quality and the antiferromagnetic transition temperature T_(N).By substituting In with Ga,T_(N) is slightly decreased,but the antiferromagnetic transition peaks in magnetic susceptibility and specific heat measurements are obviously broadened by external field along c-axis.By comparing with Zn-doped Ce RhIn_(5),it can be concluded that T_(N) is dominated by electron density,and the stiffness of antiferromagnetic transition is obviously reduced by Ga substitution.The substitution effects of Ga are possibly caused by forming heterogeneous local structures,which avoids quantum critical point,superconductivity,and non-Fermi liquid states.Investigations on Gadoped Ce RhIn_(5) help to comprehend the chemical substitution effects in Ce RhIn_(5),and the interaction between heterogeneous structure and long-range antiferromagnetic states.
基金supported by the Swiss National Science Foundation(grant number 188631).
文摘The all-vanadium redox flow battery(VRFB)plays an important role in the energy transition toward renewable technologies by providing grid-scale energy storage.Their deployment,however,is limited by the lack of membranes that provide both a high energy efficiency and capacity retention.Typically,the improvement of the battery’s energy efficiency comes at the cost of its capacity retention.Herein,novel N-alkylated and N-benzylated meta-polybenzimidazole(m-PBI)membranes are used to understand the molecular requirements of the polymer electrolyte in a vanadium redox flow battery,providing an important toolbox for future research toward next-generation membrane materials in energy storage devices.The addition of an ethyl side chain to the m-PBI backbone increases its affinity toward the acidic electrolyte,thereby increasing its ionic conductivity and the corresponding energy efficiency of the VRFB cell from 70%to 78%at a current density of 200 mA cm^(-2).In addition,cells equipped with ethylated m-PBI showed better capacity retention than their pristine counterpart,respectively 91%versus 87%,over 200 cycles at 200 mA cm^(-2).The outstanding VRFB cycling performance,together with the low-cost and fluorine-free chemistry of the N-alkylated m-PBI polymer,makes this material a promising membrane to be used in next-generation VRFB systems.
基金supported by the National Key Research and Development Program of China(Grant Nos.2023YFA1406100,2018YFA0704200,2022YFA1403400 and 2021YFA1400400)the National Natural Science Foundation of China(Grant Nos.11822411 and 12274444)+2 种基金the Strategic Priority Research Program(B)of the CAS(Grant Nos.XDB25000000 and XDB33000000)K.C.Wong Education Foundation(GJTD-2020-01)AP by HBNI-RRCAT and MPCST under the FTYS program。
文摘Elucidating the relationship between spin excitations and fermiology is essential for clarifying the pairing mechanism in iron-based superconductors(FeSCs).Here,we report inelastic neutron scattering results on the hole overdoped Ba_(0.4)K_(0.6)Fe_(2)As_(2) near a Lifshitz transition,where the electron pocket at M point is nearly replaced by four hole pockets.In the normal state,the spin excitations is observed at incommensurate wave vectors with a chimney-like dispersion.By cooling down to the superconducting state,a neutron spin resonance mode emerges with a peak energy of Er=14-15 meV,weakly modulated along the L-direction.The incommensurability notably increases at low energies,giving rise to downward dispersions of the resonance mode.This behavior contrasts sharply with the upward dispersions of resonance observed in optimally doped Ba_(0.67)K_(0.33)Fe_(2)As_(2) contributed by the hole to electron scattering,but resembles those in KFe_(2)As_(2) and KCa_(2)Fe_(4)As_(4)F_(2) where the fermiology is dominated by hole pockets.These results highlight the critical role of electronic structure modifications near the Fermi level,especially in governing interband scattering under imperfect nesting conditions,which fundamentally shape the spin dynamics of FeSCs.
