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Preliminary results suggest observations from Macao Science Satellite-1 system can improve knowledge of tidal-induced magnetic fields 被引量:8
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作者 ZhengYong Ren YiPiao Huang +2 位作者 Cong Yang ChaoJian Chen Keke Zhang 《Earth and Planetary Physics》 2025年第3期586-594,共9页
This study presents preliminary results of tidal-induced magnetic field signals extracted from 9 months of data collected by the Macao Science Satellite-1(MSS-1) from November 2023 to July 2024. Tidal signals were iso... This study presents preliminary results of tidal-induced magnetic field signals extracted from 9 months of data collected by the Macao Science Satellite-1(MSS-1) from November 2023 to July 2024. Tidal signals were isolated using sequential modeling techniques by subtracting non-tidal field model predictions from observed magnetic data. The extracted MSS-1 results show strong agreement with those from the Swarm and CryoSat satellites. MSS-1 effectively captures key large-scale tidal-induced magnetic anomalies, mainly due to its unique 41-degree low-inclination orbit, which provides wide coverage of local times. This finding underscores the strong potential of MSS-1 to recover high-resolution global tidal magnetic field models as more MSS-1 data become available. 展开更多
关键词 Macao Science Satellite-1 satellite magnetic data tidal-induced magnetic fields
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A 100-degree lithospheric magnetic field model constructed using MSS-1,Swarm-A,and CHAMP satellite data 被引量:1
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作者 JiaXuan Zhang Yan Feng +3 位作者 Pan Zhang YuXuan Lin XinWu Li Ya Huang 《Earth and Planetary Physics》 2025年第3期667-676,共10页
By combining data from the Challenging Minisatellite Payload(CHAMP),Swarm-A,and newest Macao Science Satellite-1(MSS-1) missions,we constructed a lithospheric magnetic field model up to spherical harmonic degree N = 1... By combining data from the Challenging Minisatellite Payload(CHAMP),Swarm-A,and newest Macao Science Satellite-1(MSS-1) missions,we constructed a lithospheric magnetic field model up to spherical harmonic degree N = 100.To isolate the lithospheric magnetic field signals,we utilized the latest CHAOS-8(CHAMP,Φrsted,and SAC-C 8) model and MGFM(Multisource Geomagnetic Field Model) to remove nonlithospheric sources,including the core field,magnetospheric field,ocean tidal field,and ocean circulation field.Subsequently,orbit-by-orbit processing was applied to both scalar and vector data,such as spherical harmonic high-pass filtering,singular spectrum analysis,and line leveling,to suppress noise and residual signals along the satellite tracks.With an orbital inclination of only 41°,MSS-1 effectively captures fine-scale lithospheric magnetic field signals in mid-to low-latitude regions.Its data exhibit a root mean square error of only 0.77 nT relative to the final model,confirming the high quality and utility of lithospheric field modeling.The resulting model exhibits excellent consistency with the MF7(Magnetic Field Model 7),maintaining a high correlation up to N = 90 and still exceeding 0.65 at N = 100.These results demonstrate the reliability and value of MSS-1 data in global lithospheric magnetic field modeling. 展开更多
关键词 lithospheric magnetic field Macao Science Satellite-1(MSS-1) line leveling magnetic field Model 7(MF7) singular spectrum analysis
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A high-resolution lithospheric magnetic field model of China and surroundings by using CHAMP,Swarm,CSES-1,and MSS-1 satellite magnetic measurements and aeromagnetic anomaly data 被引量:1
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作者 Pan Zhang JinSong Du +5 位作者 Liang Yin Qing Yan JiaXuan Zhang HouPu Li Keke Zhang Chao Chen 《Earth and Planetary Physics》 2025年第3期686-696,共11页
The CUG_CLMFM3D series comprises high-resolution three-dimensional lithospheric magnetic field models for China and its surroundings.The first version,CUG_CLMFM3Dv1,is a spherical cap harmonic model integrating the WD... The CUG_CLMFM3D series comprises high-resolution three-dimensional lithospheric magnetic field models for China and its surroundings.The first version,CUG_CLMFM3Dv1,is a spherical cap harmonic model integrating the WDMAMv2(World Digital Magnetic Anomaly Map version 2)global magnetic anomaly grid and nearly a decade of CHAMP(Challenging Minisatellite Payload for Geophysical Research and Application)satellite vector data.It achieves a~5.7 km resolution but has limitations:the WDMAMv2 grid lacks high-resolution data in the southern Xinjiang and Tibet regions,which leads to missing small-to medium-scale anomalies,and unfiltered CHAMP data introduce low-frequency conflicts with global spherical harmonic models.Above the altitude of 150 km,correlations with global models drop below 0.9.The second version,CUG_CLMFM3Dv2,addresses these issues by incorporating 5-km-resolution aeromagnetic data and rigorously processed satellite data from CHAMP,Swarm,CSES-1(China Seismo-Electromagnetic Satellite 1),and MSS-1(Macao Science Satellite 1).The comparison analysis shows that the CUG_CLMFM3Dv2 captures finer high-frequency details and more stable long-wavelength signals,offering improved magnetic anomaly maps for further geological and geophysical studies. 展开更多
关键词 Macao Science Satellite 1 China Seismo-Electromagnetic Satellite 1 revised spherical cap harmonic analysis high resolution lithospheric magnetic field China and surroundings
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Evaluation of the lithospheric magnetic field mapped by the first year of MSS-1 data
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作者 S.Williams D.Gubbins +1 位作者 P.W.Livermore Y.Jiang 《Earth and Planetary Physics》 2025年第3期614-621,共8页
The MSS-1 satellite began mapping Earth's magnetic field in November 2023.Here,we perform a preliminary assessment of the new information provided on Earth's lithospheric magnetic field from the first 12 month... The MSS-1 satellite began mapping Earth's magnetic field in November 2023.Here,we perform a preliminary assessment of the new information provided on Earth's lithospheric magnetic field from the first 12 months of data from MSS-1.We analyze data from the low-inclination orbital tracks of MSS-1 alongside data collected contemporaneously by the Swarm mission,and compare these to models for the lithospheric field from older satellite data and to predictions from models of lithospheric magnetization from tectonic constraints.We find that 1 year of data grouped into geographical bins is sufficient to produce a robust map of lithospheric anomalies.Time series analysis reveals that bins further from the equator arrive at stable values more rapidly,while equatorial regions require 9-10months of data accumulation for stable signal recovery.The mapped data agree well with older satellite models and with predictions from a lithospheric magnetization model,with the largest mismatches suggesting that models of continental magnetization in particular require further revision.These results demonstrate the value of MSS-1's unique orbital configuration in complementing existing satellite magnetic field measurements. 展开更多
关键词 Macao Science Satellite-1 lithospheric magnetization GEOmagnetISM lithospheric magnetic field
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Minimum Attenuation of Physiologically-Patterned, 1 µTesla Magnetic Fields through Simulated Skull and Cerebral Space
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作者 Michael A. Persinger Kevin S. Saroka 《Journal of Electromagnetic Analysis and Applications》 2013年第4期151-156,共6页
To answer the queries concerning penetrability of ~1 μT, physiologically patterned, time-varying magnetic fields through the cranium, the proportions of attenuation through thicknesses and densities of ~3 times that ... To answer the queries concerning penetrability of ~1 μT, physiologically patterned, time-varying magnetic fields through the cranium, the proportions of attenuation through thicknesses and densities of ~3 times that of the human skull were measured directly. There was no reduction in the intensity of the magnetic field when two 2 cm thick dried pine boards (4.3 × 103 kg·m-3) were placed between the pairs of solenoids separated by the approximate width of the skull. Although volumes of water containing intracellular concentrations of ions did not attenuate the field intensity, placement of 290 cm2 of 2 mm sheets of duct metal reduced the amplitude by 25%. Spectra comparisons showed a clear congruence in profiles between direct measurement of the applied field and the original computer-generated pattern. These results indicate there is little validity to claims that weak, time-varying magnetic fields applied in this manner are eliminated or significantly attenuated by the human skull. 展开更多
关键词 Time-Varying magnetic fields Penetrability of the SKULL ATTENUATION Factors Physiological Concentrations of Ions 1 MicroTesla magnetic fields
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Revised global vertically integrated remanent magnetization model of the oceanic lithosphere with comparison to LCS-1 model and MSS-1 magnetic measurements 被引量:2
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作者 ShiDa Sun Hui Li +3 位作者 JinSong Du Pan Zhang Chao Chen PengFei Liu 《Earth and Planetary Physics》 2025年第3期653-666,共14页
The lithospheric magnetic field is an important component of the geomagnetic field,and the oceanic lithosphere exhibits distinct characteristics.Because of its formation mechanisms,evolutionary history,and geomagnetic... The lithospheric magnetic field is an important component of the geomagnetic field,and the oceanic lithosphere exhibits distinct characteristics.Because of its formation mechanisms,evolutionary history,and geomagnetic field polarity reversals,the oceanic lithosphere has significant remanent magnetization,which causes magnetic anomaly stripes parallel to the mid-ocean ridges.However,it is difficult to construct a high-resolution lithospheric magnetic field model in oceanic regions with relatively sparse data or no data.Using forward calculated lithospheric magnetic field data based on an oceanic remanent magnetization(ORM) model with physical and geological foundations as a supplement is a feasible approach.We first collect the latest available oceanic crust age grid,plate motion model,geomagnetic polarity timescale,and oceanic lithosphere thermal structure.Combining the assumptions that the paleo geomagnetic field is a geocentric axial dipole field and that the normal oceanic crust moves only in the horizontal direction,we construct a vertically integrated ORM model of the normal oceanic crust with a known age,including the intensity,inclination,and declination.Both the ORM model and the global induced magnetization(GIM) model are then scaled from two aspects between their forward calculated results and the lithospheric magnetic field model LCS-1.One aspect is the difference in their spherical harmonic power spectra,and the other is the misfit between the grid data over the oceans.We last compare the forward calculated lithospheric magnetic anomaly from the scaled ORM and GIM models with the Macao Science Satellite-1(MSS-1) observed data.The comparison results show that the magnetic anomalies over the normal oceanic crust regions at satellite altitude are mainly contributed by the high-intensity remanent magnetization corresponding to the Cretaceous magnetic quiet period.In these regions,the predicted and observed anomalies show good consistency in spatial distribution,whereas their amplitude differences vary across regions.This result suggests that regional ORM construction should be attempted in future work to address these amplitude discrepancies. 展开更多
关键词 oceanic remanent magnetization lithospheric magnetic field LCS-1 Macao Science Satellite-1
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An alternative regularization approach for modeling the regional lithospheric magnetic field from satellite magnetic measurements by the spherical equivalent source method and its application in Africa 被引量:1
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作者 JiangSong Gui JinSong Du +5 位作者 Pan Zhang ChangQing Yuan YuKun Li KangAn Zhao Liang Yin HouPu Li 《Earth and Planetary Physics》 2025年第3期697-710,共14页
The equivalent source(ES)method in the spherical coordinate system has been widely applied to processing,reduction,field modeling,and geophysical and geological interpretation of satellite magnetic anomaly data.Howeve... The equivalent source(ES)method in the spherical coordinate system has been widely applied to processing,reduction,field modeling,and geophysical and geological interpretation of satellite magnetic anomaly data.However,the inversion for the ES model suffers from nonuniqueness and instability,which remain unresolved.To mitigate these issues,we introduce both the minimum and flattest models into the model objective function as an alternative regularization approach in the spherical ES method.We first present the methods,then analyze the accuracy of forward calculation and test the proposed ES method in this study by using synthetic data.The experimental results from simulation data indicate that our proposed regularization effectively suppresses the Backus effect and mitigates inversion instability in the low-latitude region.Finally,we apply the proposed method to magnetic anomaly data from China Seismo-Electromagnetic Satellite-1(CSES-1)and Macao Science Satellite-1(MSS-1)magnetic measurements over Africa by constructing an ES model of the large-scale lithospheric magnetic field.Compared with existing global lithospheric magnetic field models,our ES model demonstrates good consistency at high altitudes and predicts more stable fields at low altitudes.Furthermore,we derive the reduction to the pole(RTP)magnetic anomaly fields and the apparent susceptibility contrast distribution based on the ES model.The latter correlates well with the regional tectonic framework in Africa and surroundings. 展开更多
关键词 regional lithospheric magnetic field model spherical equivalent source method satellite magnetism AFRICA MSS-1 CSES-1
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Effects of gradient high-field static magnetic fields on diabetic mice 被引量:6
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作者 Biao Yu Chao Song +11 位作者 Chuan-Lin Feng Jing Zhang Ying Wang Yi-Ming Zhu Lei Zhang Xin-Miao Ji Xiao-Fei Tian Guo-Feng Cheng Wei-Li Chen Vitalii Zablotskii Hua Wang Xin Zhang 《Zoological Research》 SCIE CAS CSCD 2023年第2期249-258,共10页
Although 9.4 T magnetic resonance imaging(MRI) has been tested in healthy volunteers,its safety in diabetic patients is unclear.Furthermore,the effects of high static magnetic fields(SMFs),especially gradient vs.unifo... Although 9.4 T magnetic resonance imaging(MRI) has been tested in healthy volunteers,its safety in diabetic patients is unclear.Furthermore,the effects of high static magnetic fields(SMFs),especially gradient vs.uniform fields,have not been investigated in diabetics.Here,we investigated the consequences of exposure to 1.0-9.4 T high SMFs of different gradients(>10 T/m vs.0-10 T/m)on type 1 diabetic(T1D) and type 2 diabetic(T2D) mice.We found that 14 h of prolonged treatment of gradient(as high as 55.5 T/m) high SMFs(1.0-8.6 T) had negative effects on T1D and T2D mice,including spleen,hepatic,and renal tissue impairment and elevated glycosylated serum protein,blood glucose,inflammation,and anxiety,while 9.4 T quasi-uniform SMFs at 0-10 T/m did not induce the same effects.In regular T1D mice(blood glucose>16.7 mmol/L),the>10 T/m gradient high SMFs increased malondialdehyde(P<0.01) and decreased superoxide dismutase(P<0.05).However,in the severe T1D mice(blood glucose≥30.0 mmol/L),the>10 T/m gradient high SMFs significantly increased tissue damage and reduced survival rate.In vitro cellular studies showed that gradient high SMFs increased cellular reactive oxygen species and apoptosis and reduced MS-1 cell number and proliferation.Therefore,this study showed that prolonged exposure to high-field(1.0-8.6 T)>10 T/m gradient SMFs(35-1 380 times higher than that of current clinical MRI)can have negative effects on diabetic mice,especially mice with severe T1D,whereas 9.4 T high SMFs at 0-10T/m did not produce the same effects,providing important information for the future development and clinical application of SMFs,especially high-field MRI. 展开更多
关键词 Type 2 diabetes Type 1 diabetes magnetic resonance imaging(MRI) Gradient static magnetic field Quasi-uniform static magnetic field
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Ultrasmall Superparamagnetic Iron Oxide Nanoparticles as Positive Contrast Agents in Low‐Field Magnetic Resonance Imaging
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作者 Ogechukwu Ngwu‐Hyacinth Aaron Alford +7 位作者 Caleb SRowe Ryan Willoughby S.Abdollah Mirbozorgi Steven ARothenberg Jesse Jones Abin Sajan Venkatesh P.Krishnasamy Mark Bolding 《iRADIOLOGY》 2025年第5期372-387,共16页
Ultrasmall superparamagnetic iron oxide nanoparticles(usSPIONs)are promising alternatives to gadolinium‐based contrast agents for positive contrast enhancement in magnetic resonance imaging(MRI).Unlike larger SPIONs ... Ultrasmall superparamagnetic iron oxide nanoparticles(usSPIONs)are promising alternatives to gadolinium‐based contrast agents for positive contrast enhancement in magnetic resonance imaging(MRI).Unlike larger SPIONs that primarily function as T2/T2*negative contrast agents,usSPIONs with core diameters below 5 nm can effectively shorten T1 relaxation times,producing bright signals in T1‐weighted images.This distinct behavior stems from their unique magnetic properties,including single‐domain configurations,surface spin canting,and rapid Néel relaxation dynamics,which are particularly enhanced at low magnetic field strengths.The biocompatibility of iron oxide,efficient renal clearance pathways,and versatility for surface functionalization offer potential advantages over gadolinium‐based agents,especially regarding safety concerns related to nephrogenic systemic fibrosis and gadolinium deposition.These nanoparticles show particular promise for applications in lowfield MRI,vascular imaging,targeted molecular imaging,and theranostic platforms.Although challenges remain in optimizing synthesis methods for consistent production of monodisperse usSPIONs with tailored surface chemistry,ongoing research continues to advance their potential for clinical translation.This review explores the mechanisms,synthesis approaches,applications,and future perspectives of usSPIONs as positive contrast agents in MRI. 展开更多
关键词 iron oxide nanoparticle low‐field MRI magnetic resonance imaging magnetite and maghemite positive contrast agent superparamagnetic iron oxide nanoparticle T1 MRI contrast agent T1 relaxivity ultrasmall superparamagnetic iron oxide nanoparticle
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Synthesis of super-fine L1_(0)-FePt nanoparticles with high ordering degree by two-step sintering under high magnetic field 被引量:3
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作者 Dong Zhao Xiaoyang Wang +6 位作者 Ling Chang Wenli Pei Chun Wu Fei Wang Luran Zhang Jianjun Wang Qiang Wang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第14期178-185,共8页
Super-fine L1_(0)-Fe Pt nanoparticles(NPs)with high ordering degree were successfully prepared by a modified two-step sintering method,which includes low-temperature pre-sintering,and the high magnetic field(HMF)assis... Super-fine L1_(0)-Fe Pt nanoparticles(NPs)with high ordering degree were successfully prepared by a modified two-step sintering method,which includes low-temperature pre-sintering,and the high magnetic field(HMF)assisted post-sintering processes.The particle size of the L1_(0)-FePt NPs was obviously refined by lowering the sintering temperature.By applying the HMF during the post-sintering process,the fine size characteristics of L1_(0)-Fe Pt NPs were retained,and the ordering degree was significantly improved.The L1_(0)-Fe Pt NPs with sizes of about 4.5 nm,ordering degree of 0.940,and coercivity of 22.01 k Oe were obtained by this two-step sintering under a magnetic field of 12 T.The mechanism investigation of HMF enhancing the ordering degree indicates that the HMF enhances lattice distortion and magnetization energy(Zeeman energy).The enhanced lattice distortions cause high stress existing in the lattice,which can effectively promote the disordered-order transition.When the magnetic field reaches to 3 T,the Zeeman energy of the NPs is higher than the thermal disturbing energy of the NPs,and the magnetization effect is stronger.Therefore,the HMF(higher than 3 T)can obviously improve the disorder-order transition by lowering the energy barrier and accelerating the orderly diffusions of atoms.The HMF is a promising assistant to synthesize the L1_(0)-phase NPs with both of high ordering degree and super-fine size. 展开更多
关键词 L1_(0)-FePt nanoparticles Super-fine size Disorder-order transition High magnetic field Zeeman energy
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Thermal entanglement in two-qutrit spin-1 anisotropic Heisenberg model with inhomogeneous magnetic field
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作者 Erhan Albayrak 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期183-190,共8页
The thermal entanglement of a two-qutrit spin-1 anisotropic Heisenberg XXZ chain in an inhomogeneous magnetic field is studied in detail. The effects of the external magnetic field (B), a parameter b which controls ... The thermal entanglement of a two-qutrit spin-1 anisotropic Heisenberg XXZ chain in an inhomogeneous magnetic field is studied in detail. The effects of the external magnetic field (B), a parameter b which controls the inhomogeneity of B, and the bilinear interaction parameters Jx = Jy ≠ Jz on the thermal variation of the negativity are studied in detail. It is found that negativity N decreases when the values of magnetic field, inhomogeneity b and temperature are increasing. In addition, N remains at higher temperatures for higher values of Jz and lower values of B and b. 展开更多
关键词 NEGATIVITY XXZ model thermal entanglement QUTRIT spin-1 magnetic field
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Origin of Magnetic Fields of Stellar Objects in the Universe Based on the 5D Projection Theory
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作者 Peter C. W. Fung K. W. Wong 《Journal of Modern Physics》 2017年第4期668-746,共79页
Beginning with a 5D homogeneous universe [1], we have provided a plausible explanation of the self-rotation phenomenon of stellar objects previously with illustration of large number of star samples [2], via a 5D-4D p... Beginning with a 5D homogeneous universe [1], we have provided a plausible explanation of the self-rotation phenomenon of stellar objects previously with illustration of large number of star samples [2], via a 5D-4D projection. The origin of such rotation is the balance of the angular momenta of stars and that of positive and negative charged e-trino pairs, within a 3D &otimes;1D?void of the stellar object, the existence of which is based on conservation/parity laws in physics if one starts with homogeneous 5D universe. While the in-phase e-trino pairs are proposed to be responsible for the generation of angular momentum, the anti-phase but oppositely charge pairs necessarily produce currents. In the 5D to 4D projection, one space variable in the 5D manifold was compacted to zero in most other 5D theories (including theories of Kaluza-Klein and Einstein [3] [4]). We have demonstrated, using the Fermat’s Last Theorem [5], that for validity of gauge invariance at the 4D-5D boundary, the 4th space variable in the 5D manifold is mapped into two current rings at both magnetic poles as required by Perelman entropy mapping;these loops are the origin of the dipolar magnetic field. One conclusion we draw is that there is no gravitational singularity, and hence no black holes in the universe, a result strongly supported by the recent discovery of many stars with masses well greater than 100 solar mass [6] [7] [8], without trace of phenomena observed (such as strong gamma and X ray emissions), which are supposed to be associated with black holes. We analyze the properties of such loop currents on the 4D-5D boundary, where Maxwell equations are valid. We derive explicit expressions for the dipolar fields over the whole temperature range. We then compare our prediction with measured surface magnetic fields of many stars. Since there is coupling in distribution between the in-phase and anti-phase pairs of e-trinos, the generated mag-netic field is directly related to the angular momentum, leading to the result that the magnetic field can be expressible in terms of only the mechanical variables (mass M, radius R, rotation period P)of a star, as if Maxwell equations are “hidden”. An explanation for the occurrence of this “un-expected result” is provided in Section (7.6). Therefore we provide satisfactory answers to a number of “mysteries” of magnetism in astrophysics such as the “Magnetic Bode’s Relation/Law” [9] and the experimental finding that B-P graph in the log-log plot is linear. Moreover, we have developed a new method for studying the relations among the data (M, R, P) during stellar evolution. Ten groups of stellar objects, effectively over 2000 samples are used in various parts of the analysis. We also explain the emergence of huge magnetic field in very old stars like White Dwarfs in terms of formation of 2D Semion state on stellar surface and release of magnetic flux as magnetic storms upon changing the 2D state back to 3D structure. Moreover, we provide an explanation, on the ground of the 5D theory, for the detection of extremely weak fields in Venus and Mars and the asymmetric distribution of magnetic field on the Martian surface. We predict the equatorial fields B of the newly discovered Trappist-1 star and the 6 nearest planets. The log B?&minus;?log P graph for the 6 planets is linear and they satisfy the Magnetic Bode’s relation. Based on the above analysis, we have discovered several new laws of stellar magnetism, which are summarized in Section (7.6). 展开更多
关键词 5D Projection Theory Fermat’s Last Theorem Perelman’s Mappings Self-Rotation Dipolar magnetic field of Stars LAWS of STELLAR magnetism LAWS of STELLAR Angular Momentum magnetic Bode’s Law NON-EXISTENCE of Gravitational Singularity Semion State of Atoms in STELLAR Surface magnetic Storm Planetary magnetic field Maxwell Equations at 4D-5D Boundary magnetic fields of the trappist-1 System
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EFFECT OF ROTATING MAGNETIC FIELD ONMACROSTRUCTURE OF A CENTRIFUGALCASTING Al-1%Cu ALLOY
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作者 W.X. Han, X.H. Qin, D.Z. Li and K. Yang (Institute of Metal Research, The Chinese Academy of Sciences, Shengyang 110015, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第5期1087-1092,共6页
Rotating electromagnetic field is applied to the centrifugal casting, the macrostructure of centrifugal casting Al-1%Cu alloy stirred with driving or backing magnetic field are both examined. It is shown that both kin... Rotating electromagnetic field is applied to the centrifugal casting, the macrostructure of centrifugal casting Al-1%Cu alloy stirred with driving or backing magnetic field are both examined. It is shown that both kinds of electromagnetic filed can enforce the columnar-equiaxed transition, the driving one decrease the tendency of porosity occurring due to the increase in the bulk liquid pressure. Stirring with braking electromagnetic field produces the mixture of outer fine grains and inner coarse grains in the casting, this is analyzed to be contributed to the differences both in electric conductivity and density between the crystal and the melt, as well as skin effects. 展开更多
关键词 centrifugal casting rotating magnetic field MACROSTRUCTURE Al1%Cu alloy
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The global lithospheric field modeling based on MSS-1 and other satellites' gradient data 被引量:1
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作者 YuXuan Lin Yan Feng +2 位作者 JiaXuan Zhang XinWu Li Ya Huang 《Earth and Planetary Physics》 2025年第3期677-685,共9页
We combine gradient data from the Macao Science Satellite-1(MSS-1),CHAllenging Minisatellite Payload(CHAMP),Swarm-A,and Swarm-C satellites to develop a 110-degree lithospheric magnetic field model.We then comprehensiv... We combine gradient data from the Macao Science Satellite-1(MSS-1),CHAllenging Minisatellite Payload(CHAMP),Swarm-A,and Swarm-C satellites to develop a 110-degree lithospheric magnetic field model.We then comprehensively evaluate the performance of the model by power spectral comparisons,correlation analyses,sensitivity matrix assessments,and comparisons with existing lithospheric field models.Results showed that using near east–west gradient data from MSS-1 significantly enhances the model correlation in the spherical harmonic degree(N) range of 45–60 while also mitigating the decline in correlation at higher degrees(N > 60).Furthermore,the unique orbital characteristics of MSS-1 enable its gradient data to provide substantial contributions to modeling in the mid-to low-latitude regions.With continued data acquisition from MSS-1 and further optimization of data processing methods,the performance of the model is expected to improve. 展开更多
关键词 lithospheric magnetic field Macao Science Satellite-1 gradient data LCS-1
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Recent geomagnetic storms observed by Macao Science Satellite-1 被引量:4
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作者 Qing Yan HongBo Yao 《Earth and Planetary Physics》 EI CAS CSCD 2024年第4期565-569,共5页
Geomagnetic storms are rapid disturbances of the Earth’s magnetosphere.They are related to many geophysical phenomena and have large influences on human activities.Observing and studying geomagnetic storms is thus of... Geomagnetic storms are rapid disturbances of the Earth’s magnetosphere.They are related to many geophysical phenomena and have large influences on human activities.Observing and studying geomagnetic storms is thus of great significance to both scientific research and geomagnetic hazards prevention.The Macao Science Satellite-1(MSS-1)project includes two high-precision Chinese geomagnetic satellites successfully launched on May 21,2023.The main purpose of MSS-1 is to accurately measure the Earth’s magnetic field.Here,we analyze early MSS-1 geomagnetic field measurements and report observations of two recent geomagnetic storms that occurred on March 24,2024 and May 11,2024.We also calculate the related geoelectric fields as an initial step towards a quantitative assessment of geomagnetic hazards. 展开更多
关键词 Macao Science Satellite-1 geomagnetic storms satellite magnetics electromagnetic induction geoelectric fields
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The behavior of a lithospheric magnetization and magnetic field model 被引量:1
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作者 PengFei Liu Yi Jiang +1 位作者 Qing Yan Ann MHirt 《Earth and Planetary Physics》 EI CSCD 2023年第1期66-73,共8页
The Earth’s“lithosphere”is its outer shell,made up of the Earth’s crust and outermost mantle.The part of the Earth’s magnetic field that originates in the lithosphere consists of a superposition of magnetic anoma... The Earth’s“lithosphere”is its outer shell,made up of the Earth’s crust and outermost mantle.The part of the Earth’s magnetic field that originates in the lithosphere consists of a superposition of magnetic anomalies with a broad spectrum of sizes and intensities,which arise from geological and tectonic features.The lithospheric magnetic field is known from surface observations,and on larger scales from above-surface measurements.The increase in recent decades of satellites dedicated to measuring the Earth’s magnetic field has improved significantly our models of the Earth’s magnetic environment.Based on these increasing observations,a number of comprehensive field models have been constructed,some of which focus solely on the lithosphere,such as the MF model series.We present a map of lithospheric magnetic anomalies at 400 km altitude,based on a vertically integrated magnetization model.This height was chosen because it is the expected orbital altitude of the Macao Science Satellite-1(MSS-1)mission.The model presented herein indicates that the amplitude of the lithospheric anomalies at 400 km altitude is between-14.8 n T and 18.2 n T.This information is useful because it provides a reference for the lithospheric source of the Earth’s magnetic field that contributes to the magnetic measurements made from satellite instruments.The low inclination orbit of the MSS-1 mission will provide information that is sensitive to lateral variation within the lithosphere;these variations arise from plate tectonic features with longitudinal extent.In conclusion,the new MSS-1mission will provide valuable information in detecting compositional variations in the lithosphere,and in delineating large-scale geological structures. 展开更多
关键词 vertically integrated magnetization lithospheric magnetic field field model MSS-1
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Time delay and extended halo for constraints on the intergalactic magnetic field
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作者 Yuan-Pei Yang Zi-Gao Dai 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第12期2173-2186,共14页
Primary gamma rays emitted from extragalactic very-high-energy (VHE) sources, such as blazars, will generate cascade radiation in intergalactic space with a scale of -- 100 Mpc, for z - 0.1 and Eγ -1 TeV. These cas... Primary gamma rays emitted from extragalactic very-high-energy (VHE) sources, such as blazars, will generate cascade radiation in intergalactic space with a scale of -- 100 Mpc, for z - 0.1 and Eγ -1 TeV. These cascades proceed through electron-positron pair production and inverse Compton (IC) scattering in the cosmic background radiation fields, mainly cosmic microwave background (CMB) radiation and extragalactic background light in the voids of the universe. The existence of an intergalactic magnetic field (IGMF) would deflect paths of electron-positron pairs that scatter CMB photons, causing some observable effects, such as time delay, an ex- tended halo, and a spectral change. Here we reanalyze the diffusion of an electron jet deflected by IGMF and propose a unified semi-analytical model. By using publicly available data from the Fermi/LAT detector and contemporaneous TeV observations, we find that the cascade photon flux is not significantly affected by the IGMF strength for non-variable blazars when the IGMF is weaker than ,-~ 10-16 G. This result is clearly different from previous works that analyzed the extended halo and time de- lay separately for non-variable blazars and flaring blazars. By applying our model to two extreme blazars (1ES 0229+200 and 1ES 1218+304), we obtain the IGMF lower limit of order ≥10-13 --10-14 G in the non-variable case, which is a stronger constraint on the IGMF strength than previous works (≥10-16 ,-- 10-18 G), and ≥10-18 -- 10-19 G in the case of flaring blazars. Furthermore, we study the light curves and extended halo of the cascade photons by considering the effects of the IGME 展开更多
关键词 gamma rays: general -- galaxies: magnetic field -- galaxies: individual(1ES 0229+200 1ES 1218+304)
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Mossbauer study of martensitic transformation andcollective magnetic excitations in Fe_9Ni.1 fine particles
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作者 黄润生 夏元复 +2 位作者 李世民 王锦辉 陆怀先 《Nuclear Science and Techniques》 SCIE CAS CSCD 1996年第4期215-218,共4页
Mossbauerstudyofmartensitictransformationandcollective magnetic excitationsinFe_9Ni.1fine particlesH.M.Widat... Mossbauerstudyofmartensitictransformationandcollective magnetic excitationsinFe_9Ni.1fine particlesH.M.Widatallah,HuangRun-Sh?.. 展开更多
关键词 马氏体式变换 Fe9Ni磁激活 穆斯堡尔效应
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Cosmic Ether, Possessing Electric-Tension and Magnetic-Resistance, Is the Unified Field for Physics 被引量:1
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作者 Chandrasekhar Roychoudhuri 《Journal of Modern Physics》 2021年第5期671-699,共29页
The paper presents the case that physics is already and effectively unified by the energetic tension field, ether. We identify this integrating power of ether first, by re-defining the action generating parameters of ... The paper presents the case that physics is already and effectively unified by the energetic tension field, ether. We identify this integrating power of ether first, by re-defining the action generating parameters of this energetic tension field as the electric-tension, <img src="Edit_1233fa02-9a1c-416a-8153-196733a12887.png" alt="" />, and the magnetic-resistance, <em>μ</em><sub>0</sub>, while re-deriving the Maxwell’s wave equation in analogy with the mechanically stretched string, where the <img src="Edit_07813a1b-d94f-4e68-a3ed-b3023cd3fb5f.png" alt="" />. Then, replacing <img src="Edit_7d06fa1e-760d-4b80-a503-db81378a3512.png" alt="" /> by <img src="Edit_58f15ef0-2e86-42ae-a899-d0b4741f12d0.png" alt="" /> and <em>m</em><sub>0</sub> by <img src="Edit_f8cb7020-1a27-404a-b146-5c1357e1c5b5.png" alt="" />, one can find that almost all working physics theories are being energized by<img src="Edit_f860fcdd-1dc1-40bf-aaf1-e07b0e4a7524.png" alt="" />and <em>μ</em><sub>0</sub>. To complete the unification, we can now postulate that the particles are also freely propagating EM waves, but they are spatially localized as in-phase, close-looped (IP-CL) vortex-like propagation modes of ether. Because of their IP-CL mode structure, they have space-finite spatial structures and remain spatially stationary in the absence of any spatially influencing potential gradients (forces) in their vicinity. Particles’ <em>harmonic phase</em> driven interactions between quantum particles give birth to the <em>appearance</em> of wave-particle duality. There is no need for the confusing and unnecessary de Broglie’s Pilot Wave. The inertia to spatial motion of IP-CL modes automatically accommodates Newton’s laws of motion. The cosmic universality of Maxwellian wave velocity, and particles as IP-CL modes, jointly accommodate the two key postulates of special relativity without the need for unphysical four-dimensionality. The observable universe is represented only by its diverse oscillatory excited states. The stable and stationary Cosmic Ether keeps holding 100% of its energy all the time. We have proposed a one-way light pulse propagation experiment to directly validate the existence of ether, rather than approaching Michelson’s way of measuring the ether drag. We have identified a good number of examples of working theoretical expressions in terms of <img src="Edit_fd739625-efbd-4edd-9e1e-ba4ab5b7c07f.png" alt="" />and<em> μ</em><sub>0</sub> and presented our critical views in physics thinking, belonging to Classical, Relativity, Quantum and Cosmology Physics. 展开更多
关键词 Cosmic Ether Ether as the Unifying field Ether Energetic Tension field (1/ε0)-Electric Tension of Ether μ0-magnetic Resistance of Ether Particles as Localized EM Oscillating Modes of Ether
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Mars Orbiter magnetometer of China’s First Mars Mission Tianwen-1 被引量:13
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作者 Kai Liu XinJun Hao +7 位作者 YiRen Li TieLong Zhang ZongHao Pan ManMing Chen XiaoWen Hu Xin Li ChengLong Shen YuMing Wang 《Earth and Planetary Physics》 CSCD 2020年第4期384-389,共6页
As one of the seven scientific payloads on board the Tianwen-1 orbiter,the Mars Orbiter Magnetometer(MOMAG)will measure the magnetic fields of and surrounding Mars to study its space environment and the interaction wi... As one of the seven scientific payloads on board the Tianwen-1 orbiter,the Mars Orbiter Magnetometer(MOMAG)will measure the magnetic fields of and surrounding Mars to study its space environment and the interaction with the solar wind.The instrument consists of two identical triaxial fluxgate magnetometer sensors,mounted on a 3.19 meter-long boom with a seperation of about 90 cm.The dual-magnetometers configuration will help eliminate the magnetic field interference generated by the spacecraft platform and payloads.The sensors are controlled by an electric box mounted inside the orbiter.Each magnetometer measures the ambient vector magnetic field over a wide dynamic range(to 10,000 nT per axis)with a resolution of 1.19 pT.Both magnetometers sample the ambient magnetic field at an intrinsic frequency of 128 Hz,but will operate in a model with alternating frequency between 1 and 32 Hz to meet telemetry allocations. 展开更多
关键词 MARS magnetic field magnetOMETER Tianwen-1 spaceflight instrumentation
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