Despite the rapid progress in the study of planar Hall effect(PHE)in recent years,all the previous works only showed that the PHE is connected to local geometric quantities,such as Berry ***,for the first time,we poin...
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Despite the rapid progress in the study of planar Hall effect(PHE)in recent years,all the previous works only showed that the PHE is connected to local geometric quantities,such as Berry ***,for the first time,we point out that the PHE in magnetic Weyl semimetals is directly related to a global quantity,namely,the Chern number of the Weyl *** leads to a remarkable consequence that the PHE observation predicted here is robust against many system details,including the Fermi *** main difference between non-magnetic and magnetic Weyl points is that the latter breaks time-reversal symmetry T,thus generally possessing an energy *** semiclassical Boltzmann theory,we investigate the PHE in generic magnetic Weyl models with energy tilt and arbitrary Chern *** find that by aligning the magnetic and electric fields in the same direction,the trace of the PHE conductivity contributed by Berry curvature and orbital moment is proportional to the Chern number and the energy tilt of the Weyl points,resulting in a previously undiscovered quantized PHE plateau by varying the Fermi *** further confirm the existence of PHE plateaus in a more realistic lattice model without T *** proposing a new quantized physical quantity,our work not only provides a new tool for extracting the topological character of the Weyl points but also suggests that the interplay between topology and magnetism can give rise to intriguing physics.
For the first time,we have introduced the tetrahedron constellation of gravitational wave observatory(TEGO)composed of four identical spacecrafts(S/Cs).The laser telescopes and their pointing structures are mounted on...
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For the first time,we have introduced the tetrahedron constellation of gravitational wave observatory(TEGO)composed of four identical spacecrafts(S/Cs).The laser telescopes and their pointing structures are mounted on the S/C platform and are evenly distributed at three locations 120 degrees *** structures form automatically a stable mass center for the *** time delay interferometry(TDI)is used to suppress the frequency noise of gravitational wave(GW)*** unequal-arm Michelson TDI configuration and the Sagnac TDI configuration are equally effective at eliminating the laser frequency noise based on the TEGO ***,compared with the configurations of LISA,Taiji,and Tian Qin,the TEGO has more combinations of optical paths in its TDI system sensitive to GW *** six arms of TEGO are simultaneously sensitive to the six polarization modes of *** sensitivity implies that GW modes beyond the predictions of general relativity(GR)can be detected *** instance,a scalar longitudinal mode of GWs,which is not predicted by GR,has been identified as a dominant polarization *** mode is found to be evident in the response amplitudes of the TEGO arms,such as between S/C1 and S/C4,and S/C3 and S/C4,at certain orbital positions.
For space-based gravitational wave(GW)detection,the main noise source for massive black hole binaries(MBHBs)is attributed to approximately 107 double white dwarf binaries in the *** a GW source,the amplitude of the de...
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For space-based gravitational wave(GW)detection,the main noise source for massive black hole binaries(MBHBs)is attributed to approximately 107 double white dwarf binaries in the *** a GW source,the amplitude of the detector response,recorded by a space-based gravitational wave detector,exhibits a modulation effect with a year period when observing the source from various orbital *** the adverse conditions mentioned above,where there is a strong foreground noise and annual modulation in the signals,we employed the wavelet transform and the strong-amplitude relevant orbital position search methods,which allows the weak MBHB sources to achieve higher locating *** detail,for two MBHB sources of lower intensity,the precision of luminosity distance,represented by the ratioΔD_(L)/D_(L) at the 95%confidence level,is enhanced by factors of∼*** angular resolutions,denoted byΔΩs,are enhanced by a factor of∼*** improvements increase the number of detectable GW sources,facilitate multi-messenger follow-up observations and provide constraints on the cosmological constant.
The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression *** establishing the constitutive equations for simulating th...
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The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression *** establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(Q)maps and processing maps for identifying the region of flow *** concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present.
This study examines the spillover effects of international film co-production using data on films released in the Chinese mainland from 2006 to *** results indicate that local film producers can enhance their product ...
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This study examines the spillover effects of international film co-production using data on films released in the Chinese mainland from 2006 to *** results indicate that local film producers can enhance their product performance by leveraging the expertise and practices of more sophisticated foreign firms during international *** effects were observed related to budget size,firm size,ownership structure,and cultural *** spillover effects can occur through two mechanisms:the demonstration effect(the adoption of more advanced technology)and the labor mobility effect(actors or directors upgrading their skills).An instrumental variable approach is employed to address endogeneity *** study contributes to the spillover effects of international co-production,which has been neglected in the *** empirical findings suggest that engaging in international co-production can potentially boost productivity for firms from developing *** country governments may consider offering preferential policies to promote international co-production as an alternative to foreign direct investment(FDI),thereby fostering positive spillover effects.
S and Co co-doped carbon catalysts were prepared via pyrolysis of MOF-71 and thiourea mixtures at 800℃at a mass ratio of MOF-71 to thiourea of 1:0.1 to effectively activate peroxymonosulfate(PMS)for methylene blue(MB...
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S and Co co-doped carbon catalysts were prepared via pyrolysis of MOF-71 and thiourea mixtures at 800℃at a mass ratio of MOF-71 to thiourea of 1:0.1 to effectively activate peroxymonosulfate(PMS)for methylene blue(MB)*** effects of two different mixing routes were identified on the MB degradation ***,the catalyst obtained by the alcohol solvent evaporation(MOF-AEP)mixing route could degrade 95.60%MB(50 mg/L)within 4 min(degradation rate:K=0.78 min^(-1)),which was faster than that derived from the direct grinding method(MOF-DGP,80.97%,K=0.39 min^(-1)).X-ray photoelectron spectroscopy revealed that the Co-S content of MOF-AEP(43.39at%)was less than that of MOF-DGP(54.73at%),and the proportion of C-S-C in MOF-AEP(13.56at%)was higher than that of MOF-DGP(10.67at%).Density functional theory calculations revealed that the adsorption energy of Co for PMS was -2.94 eV when sulfur was doped as C-S-C on the carbon skeleton,which was higher than that when sulfur was doped next to cobalt in the form of Co-S bond(-2.86 eV).Thus,the C-S-C sites might provide more contributions to activate PMS compared with ***,the degradation parameters,including pH and MOF-AEP dosage,were ***,radical quenching experiments and electron paramagnetic resonance(EPR)measurements revealed that ^(1)O_(2)might be the primary catalytic species,whereas·O~(2-)might be the secondary one in degrading MB.
This study primarily investigates the rock fracture mechanism of bottom cushion layer blasting and explores the effects of the bottom cushion layer on rock *** involves analyses of the evolution patterns of blasting s...
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This study primarily investigates the rock fracture mechanism of bottom cushion layer blasting and explores the effects of the bottom cushion layer on rock *** involves analyses of the evolution patterns of blasting stress,characteristics of crack distribution,and rock fracture features in the ***,blasting model experiments were carried out using the dynamic caustics principle to investigate the influence of bottom cushion layers and initiation methods on the integrity of the bottom rock *** experimental results indicate that the combined use of bottom cushion layers and inverse initiation effectively protects the integrity of the bottom rock ***,the process of stress wave propagation and dynamic crack propagation in rocks was simulated using the continuum-discontinuum element method(CDEM)and the Landau explosion source model,with varying thicknesses of bottom cushion *** numerical simulation results indicate that with increasing cushion thickness,the absorption of energy generated by the explosion becomes more pronounced,resulting in fewer cracks in the bottom rock *** illustrates the positive role of the cushion layer in protecting the integrity of the bottom rock mass.
Civil aviation is one of the industries facing the greatest challenge in reaching carbon neutrality by the middle of this century,and this sector also contributes to adverse impacts on the regional air quality and hum...
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Civil aviation is one of the industries facing the greatest challenge in reaching carbon neutrality by the middle of this century,and this sector also contributes to adverse impacts on the regional air quality and human *** exhibits the second highest air passenger turnover *** understanding of civil aviation emissionsmust be urgently enhanced,and themitigation potential should be *** this study,on the basis of real domestic flight information for 2019,we built a greenhouse gas and air pollution emission inventory for the civil aviation sector in China with the fuel flowmethod based on the cruise and other *** thoroughly analyzed emissions by region,aircraft and engine types,and aircraft age,based on which we designed four measures to evaluate the abatement *** found that the hydrocarbon(HC),CO,NO_(x),SO_(2),particulate matter(PM)and CO_(2)emissions in 2019 reached 79.9 kt(95%CI[51.6–114.5]),176.3 kt(95%CI[114.5–248.2]),304.2 kt(95%CI[203.4–420.7]),23.2 kt(95%CI[14.2–33.7]),1.0 kt(95%CI[0.61–1.44])and 87.0 Mt(95%CI[57.4–119.6]),*** cruise phase was the major emission phase,accounting for 67%-87%of the total pollutant *** four measures were jointly implemented,the HC,CO,NO_(x),SO_(2),PM and CO_(2)emissions could be reduced by 61%,54%,55%,45%,32%and 38%,*** lower-emission aircraft and switching travel modes could substantially reduce civil aviation emissions in China.
The aim of this study was to assess the potential of surgical guides as a complementary tool to augmented reality(AR)in enhancing the safety and precision of pedicle screw placement in spinal *** trainers were divided...
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The aim of this study was to assess the potential of surgical guides as a complementary tool to augmented reality(AR)in enhancing the safety and precision of pedicle screw placement in spinal *** trainers were divided into the AR navigation group using surgical guides and the free-hand *** group consisted of a novice and an experienced spine surgeon.A total of 80 pedicle screws were ***,the AR group reconstructed the 3D model and planned the screw insertion route according to the computed tomography data of L2 lumbar ***,the Microsoft HoloLens™2 was used to identify the vertebral model,and the planned virtual path was superimposed on the real cone ***,the screw was placed according to the projected ***,Micron Tracker was used to measure the deviation of screws from the preoperatively planned trajectory,and pedicle screws were evaluated using the Gertzbein-Robbins *** the AR group,the linear deviations of the experienced doctor and the novice were(1.59±0.39)mm and(1.73±0.52)mm respectively,and the angle deviations were 2.72°±0.61°and 2.87°±0.63°*** the free-hand group,the linear deviations of the experienced doctor and the novice were(2.88±0.58)mm and(5.25±0.62)mm respectively,and the angle deviations were 4.41°±1.18°and 7.15°±1.45°*** kinds of deviations between the two groups were significantly different(Pstudy indicate that the integration of surgical guides and AR is an innovative technique that can substantially enhance the safety and precision of spinal surgery and assist inexperienced doctors in completing the surgery.
Recent progress in microwave absorption materials stimulates the extensive exploration of rare earth oxide ***,we report the synthesis of a hollow sphere-based carbon material compounded with rare earth *** N-doped ca...
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Recent progress in microwave absorption materials stimulates the extensive exploration of rare earth oxide ***,we report the synthesis of a hollow sphere-based carbon material compounded with rare earth *** N-doped carbon nano-spheres loaded ceria composites(H-NC@CeO_(2))were designed and prepared by the template method,combined with in-situ coating,pyrolysis and chemical *** controlling the loading content of H-NC@CeO_(2)and adjusting the impedance matching of the material,the H-NC@CeO_(2)/PS(polystyrene)composite exhibited a minimum reflection loss(RL)of-50.8 dB and an effective absorption band-width(EAB)of 4.64 GHz at a filler ratio of 20wt%and a thickness of 2 *** accordance with measured electromagnetic parameters,simulations using the high frequency structure simulator(HFSS)software were conducted to investigate the impact of the honeycomb structure on the electromagnetic wave performance of H-NC@CeO_(2)/*** calculating the surface electric field and the material’s bulk loss density,the mechanism of electromagnetic loss for the honeycomb structure was elaborated.A method for structural design and man-ufacturing of broadband absorbing devices was proposed and a broadband absorber with an EAB of 11.9 GHz was *** study presents an innovative approach to designing advanced electromagnetic(EM)wave absorbing materials with broad absorption band-widths.
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