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Rapid multiplex pathogen detection using 96-channel microfluidic chip with magnetic bead method
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作者 Enjia Zhang Jiaying Cao +6 位作者 Jianxin Cheng Gaozhe Cai Shuyue Jiang Weiwei Xie Chunping Jia Jianlong Zhao Shilun Feng 《Chinese Chemical Letters》 2026年第2期635-642,共8页
The implementation of multiple pathogen testing is essential for a rapid response to future outbreaks and for reducing disease transmission.This study introduces a 96-channel microfluidic chip,fabricated through a mol... The implementation of multiple pathogen testing is essential for a rapid response to future outbreaks and for reducing disease transmission.This study introduces a 96-channel microfluidic chip,fabricated through a molding process,which enables the batch detection of pathogens.It explores the rapid lysis and elution processes of pathogens within the microfluidic chips to ensure that nucleic acid extraction,elution,and amplification are completed entirely within the chip.This chip can extract nucleic acids from samples in just 10 min,achieving an extraction efficiency comparable to that of traditional in-tube methods.An oil phase is pre-loaded into the chip to effectively prevent aerosol contamination.This approach allows for the simultaneous detection of 21 common respiratory pathogens,with a detection limit of 10 copies per reaction.Furthermore,applications involving clinical samples demonstrate significant practicality.Compared to many traditional in-tube pathogen detection methods and molecular biology technologies that utilize microfluidic chips,this detection chip not only enables simultaneous detection of multiple pathogens but also demonstrates high sensitivity. 展开更多
关键词 96-Channel microfuild chip Multiplex pathogen detection magnetic bead method Respiratory pathogens
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Detection of the Oscillation Marks on Casting Slabs Using Magnetic Flux Variation and the Nonexcitation Method
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作者 FENG Kaibin LIU Runcong +3 位作者 LI Silong WU Yunfei NA Xianzhao WANG Xiaodong 《材料导报》 北大核心 2026年第1期149-158,共10页
T he residual stray magnetic fields present in ferromagnetic casting slabs were investigated in this work,which result from the magnetic fields generated during the steel casting process.Existing optical detection met... T he residual stray magnetic fields present in ferromagnetic casting slabs were investigated in this work,which result from the magnetic fields generated during the steel casting process.Existing optical detection methods face challenges owing to surface oxide scales,and conventional high-precision magnetic sensors are ineffective at high temperatures.To overcome these limitations,a small coil sensor was employed to measure the residual magnetism strength in oscillation traces,using metal magnetic memory and electromagnetic induction methods,which can carry out detection without an external excitation source.Using this technology,the proposed scheme successfully detects defects at high tempe-ratures(up to 670℃)without a cooling device.The key findings include the ability to detect both surface and near-surface defects,such as cracks and oscillation marks,with an enhanced signal-to-noise ratio(SNR)of 7.2 dB after signal processing.The method’s practicality was validated in a steel mill environment,where testing on casting slabs effectively detected defects,providing a foundation for improving industrial quality control.The proposed detection scheme offers a significant advancement in nondestructive testing(NDT)for high-temperature applications,contributing to more efficient and accurate monitoring of ferromagnetic material integrity. 展开更多
关键词 oscillation marks REMANENCE metal magnetic memory near surface defects nondestructive testing(NDT)
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Research on the Testing Methods of Instrumental System in the Marine Magnetic Survey 被引量:1
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作者 边刚 刘雁春 +2 位作者 于波 肖付民 卞光浪 《Marine Science Bulletin》 CAS 2007年第2期1-11,共11页
Testing methods of instrumental system in the marine magnetic survey have been studied in this paper, and the feasibility of each method has been testified by the observed data. The conclusion shows that the method br... Testing methods of instrumental system in the marine magnetic survey have been studied in this paper, and the feasibility of each method has been testified by the observed data. The conclusion shows that the method brought out can effectively eliminate the systematic error caused by the instrumental system, and greatly improve the surveying precision and the reliability of the survey results. 展开更多
关键词 Marine magnetic survey instrumental system testing method
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SLM-3D Printed Soft Magnetic Alloys:Process,Performance,and Prospects
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作者 Liu Bingxu You Caiyin +4 位作者 Wang Fenghui Tian Na Liu Heguang Zhang Jing Zhu Xiaopei 《稀有金属材料与工程》 北大核心 2026年第2期365-388,共24页
Soft magnetic alloys are extensively used in various power electronic devices due to their advantageous properties,including high saturation magnetic induction,low coercivity,and high permeability.In certain applicati... Soft magnetic alloys are extensively used in various power electronic devices due to their advantageous properties,including high saturation magnetic induction,low coercivity,and high permeability.In certain applications,complex-shaped components are increasingly required for performance enhancement.Additive manufacturing technique,particularly selective laser melting(SLM),has emerged as an effective method for fabricating such complex-shaped soft magnetic components.SLM,a laserbased additive manufacturing technique,employs high-power-density lasers to melt and fuse metal powders within a powder bed selectively.This approach enables rapid prototyping,precise geometrical control,and the integration of multi-material designs.This review highlights recent advancements in the application of SLM technique for the production of soft magnetic alloys,focusing on Fe-Si,Fe-Ni,Fe-Co,and amorphous alloy systems.Moreover,it explores the implementation of SLM in manufacturing processes and evaluates both the opportunities and challenges associated with SLM-based production of soft magnetic alloys. 展开更多
关键词 additive manufacturing selective laser melting soft magnetic alloys magnetic properties
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Optimizing Magnetic Performance and Microstructure of CoPt Nanoparticles by Sol-Gel Synthesis
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作者 WANG Xinchi WANG Wei +2 位作者 LIU Shuai WANG Yun LI Baohe 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期8-14,共7页
We prepared Co_(x)Pt_(100-x)(x=40,45,50,55,60)nanoparticles by the sol-gel method.The phase composition and crystal structure,morphology and microstructure,and magnetic properties of the samples were characterized and... We prepared Co_(x)Pt_(100-x)(x=40,45,50,55,60)nanoparticles by the sol-gel method.The phase composition and crystal structure,morphology and microstructure,and magnetic properties of the samples were characterized and tested using X-ray diffraction(XRD),transmission electron microscopy(TEM),and vibrating sample magnetometer(VSM),respectively.The results demonstrate that the coercivity of CoPt nanoparticles can be effectively controlled by adjusting the atomic ratio of Co and Pt in the samples.Among the compositions studied,the Co_(45)Pt_(55)sample synthesized by the sol-gel method exhibits smaller grain size and a coercivity as high as 6.65×10^(5) A/m is achieved.The morphology and microstructure of the nanoparticles were analyzed by TEM images,indicating that a slight excess of Pt can effectively enhance the coercivity of CoPt nanoparticles. 展开更多
关键词 COPT sol-gel method atomic ratio magnetic nanoparticles COERCIVITY
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Microstructure and Properties of Mg/Fe Dissimilar Metal Joints Fabricated by Magnetic Pulse Welding
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作者 Xie Jilin Li Shimeng +3 位作者 Wang Yaping Liu Dongya Liu Xiaofang Chen Yuhua 《稀有金属材料与工程》 北大核心 2026年第1期67-77,共11页
Dissimilar AZ31B magnesium alloy and DC56D steel were welded via AA1060 aluminum alloy by magnetic pulse welding.The effects of primary and secondary welding processes on the welded interface were comparatively invest... Dissimilar AZ31B magnesium alloy and DC56D steel were welded via AA1060 aluminum alloy by magnetic pulse welding.The effects of primary and secondary welding processes on the welded interface were comparatively investigated.Macroscopic morphology,microstructure,and interfacial structure of the joints were analyzed using scanning electron microscope,energy dispersive spectrometer,and X-ray diffractometer(XRD).The results show that magnetic pulse welding of dissimilar Mg/Fe metals is achieved using an Al interlayer,which acts as a bridge for deformation and diffusion.Specifically,the AZ31B/AA1060 interface exhibits a typical wavy morphology,and a transition zone exists at the joint interface,which may result in an extremely complex microstructure.The microstructure of this transition zone differs from that of AZ31B magnesium and 1060 Al alloys,and it is identified as brittle intermetallic compounds(IMCs)Al_(3)Mg_(2) and Al_(12)Mg_(17).The transition zone is mainly distributed on the Al side,with the maximum thickness of Al-side transition layer reaching approximately 13.53μm.Incomplete melting layers with varying thicknesses are observed at the primary weld interface,while micron-sized hole defects appear in the transition zone of the secondary weld interface.The AA1060/DC56D interface is mainly straight,with only a small number of discontinuous transition zones distributed intermittently along the interface.These transition zones are characterized by the presence of the brittle IMC FeAl_(3),with a maximum thickness of about 4μm. 展开更多
关键词 magnetic pulse welding mechanical properties MICROSTRUCTURE fracture morphology primary and secondary welding
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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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Ligand-directed construction of cobalt-oxo cluster-based organic frameworks:Structural modulation,semiconductor,and antiferromagnetic properties
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作者 SHI Jinlian LIU Xiaoru XU Zhongxuan 《无机化学学报》 北大核心 2026年第1期45-54,共10页
Under hydrothermal and solvothermal conditions,two novel cobalt-based complexes,{[Co_(2)(CIA)(OH)(1,4-dtb)]·3.2H_(2)O}n(HU23)and{[Co_(2)(CIA)(OH)(1,4-dib)]·3.5H2O·DMF}n(HU24),were successfully construct... Under hydrothermal and solvothermal conditions,two novel cobalt-based complexes,{[Co_(2)(CIA)(OH)(1,4-dtb)]·3.2H_(2)O}n(HU23)and{[Co_(2)(CIA)(OH)(1,4-dib)]·3.5H2O·DMF}n(HU24),were successfully constructed by coordinatively assembling the semi-rigid multidentate ligand 5-(1-carboxyethoxy)isophthalic acid(H₃CIA)with the Nheterocyclic ligands 1,4-di(4H-1,2,4-triazol-4-yl)benzene(1,4-dtb)and 1,4-di(1H-imidazol-1-yl)benzene(1,4-dib),respectively,around Co^(2+)ions.Single-crystal X-ray diffraction analysis revealed that in both complexes HU23 and HU24,the CIA^(3-)anions adopt aκ^(7)-coordination mode,bridging six Co^(2+)ions via their five carboxylate oxygen atoms and one ether oxygen atom.This linkage forms tetranuclear[Co4(μ3-OH)2]^(6+)units.These Co-oxo cluster units were interconnected by CIA^(3-)anions to assemble into 2D kgd-type structures featuring a 3,6-connected topology.The 2D layers were further connected by 1,4-dtb and 1,4-dib,resulting in 3D pillar-layered frameworks for HU23 and HU24.Notably,despite the similar configurations of 1,4-dtb and 1,4-dib,differences in their coordination spatial orientations lead to topological divergence in the 3D frameworks of HU23 and HU24.Topological analysis indicates that the frameworks of HU23 and HU24 can be simplified into a 3,10-connected net(point symbol:(4^(10).6^(3).8^(2))(4^(3))_(2))and a 3,8-connected tfz-d net(point symbol:(4^(3))_(2)((4^(6).6^(18).8^(4)))),respectively.This structural differentiation confirms the precise regulatory role of ligands on the topology of metal-organic frameworks.Moreover,the ultraviolet-visible absorption spectra confirmed that HU23 and HU24 have strong absorption capabilities for ultraviolet and visible light.According to the Kubelka-Munk method,their bandwidths were 2.15 and 2.08 eV,respectively,which are consistent with those of typical semiconductor materials.Variable-temperature magnetic susceptibility measurements(2-300 K)revealed significant antiferromagnetic coupling in both complexes,with their effective magnetic moments decreasing markedly as the temperature lowered.CCDC:2457554,HU23;2457553,HU24. 展开更多
关键词 semi-rigid carboxylic acid ligands three-dimensional framework tetranuclear cobalt-oxo cluster semiconductor material antiferromagnetic magnetism
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Optimal Reconfiguration Trajectory of Multi-satellite Electromagnetic Formation System
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作者 CHU Wenbo ZHOU Qingrui +1 位作者 LIU Zhongxin NI Yuanhua 《空间控制技术与应用(中英文)》 北大核心 2026年第1期37-47,共11页
The multi-satellite electromagnetic formation flight system is nonlinear and strongly coupled,which makes modeling and optimization challenging.To simplify electromagnetic force evaluation and dynamics modeling,we int... The multi-satellite electromagnetic formation flight system is nonlinear and strongly coupled,which makes modeling and optimization challenging.To simplify electromagnetic force evaluation and dynamics modeling,we introduce a reference frame consistent with each satellite body frame,in which the electromagnetic dipoles and electromagnetic forces are represented as two-dimensional vectors.Then,the maneuver time is divided into time intervals,and different satellite sets are activated in each interval,converting the multi-satellite formation reconfiguration problem into an optimal trajectory problem of each two-satellite subsystem.To this end,a token-based dynamic programming method with a switching penalty of active satellite sets is proposed to determine the sequence of satellite sets participating in each time interval,thereby enabling all satellites to reach their desired states.For the two-satellite subsystem with the objectives of minimizing maneuver time and energy consumption,the Gauss pseudo-spectral method is employed to generate the optimal reconfiguration trajectory.Numerical simulations verify the effectiveness of the proposed optimization method. 展开更多
关键词 electromagnetic formation flight Gauss pseudo-spectral method token-based dynamic programming
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Lithospheric magnetic variations on the Tibetan Plateau based on a 3D surface spline model,compared with strong earthquake occurrences
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作者 PengTao Zhang Jun Yang +3 位作者 LiLi Feng Xia Li YuHong Zhao YingFeng Ji 《Earth and Planetary Physics》 2026年第1期30-43,共14页
The National Geophysical Data Center(NGDC)of the United States has collected aeromagnetic data for input into a series of geomagnetic models to improve model resolution;however,in the Tibetan Plateau region,ground-bas... The National Geophysical Data Center(NGDC)of the United States has collected aeromagnetic data for input into a series of geomagnetic models to improve model resolution;however,in the Tibetan Plateau region,ground-based observations remain insufficient to clearly reflect the characteristics of the region’s lithospheric magnetism.In this study,we evaluate the lithospheric magnetism of the Tibetan Plateau by using a 3D surface spline model based on observations from>200 newly constructed repeat stations(portable stations)to determine the spatial distribution of plateau geomagnetism,as well as its correlation with the tectonic features of the region.We analyze the relationships between M≥5 earthquakes and lithospheric magnetic field variations on the Tibetan Plateau and identify regions susceptible to strong earthquakes.We compare the geomagnetic results with those from an enhanced magnetic model(EMM2015)developed by the NGDC and provide insights into improving lithospheric magnetic field calculations in the Tibetan Plateau region.Further research reveals that these magnetic anomalies exhibit distinct differences from the magnetic-seismic correlation mechanisms observed in other tectonic settings;here,they are governed primarily by the combined effects of compressional magnetism,thermal magnetism,and deep thermal stress.This study provides new evidence of geomagnetic anomalies on the Tibetan Plateau,interprets them physically,and demonstrates their potential for identifying seismic hazard zones on the Plateau. 展开更多
关键词 Tibetan Plateau magnetic variation SEISMICITY surface spline model enhanced magnetic model
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Magnetic field enhanced electrocatalytic oxygen evolution of CoFe_(2)O_(4) with tunable oxygen vacancy concentrations
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作者 Xiangyang Zou Ping Guo +2 位作者 Yuanyuan Zhang Feng Gao Ping Xu 《Chinese Chemical Letters》 2026年第1期671-677,共7页
Magnetic field-driven spin polarization modulation has emerged as an effective way to boost the electrocatalytic oxygen evolution reaction(OER).However,the correlation among catalyst structure,magnetic property,and ma... Magnetic field-driven spin polarization modulation has emerged as an effective way to boost the electrocatalytic oxygen evolution reaction(OER).However,the correlation among catalyst structure,magnetic property,and magnetic field enhanced-electrochemical activity remains to be fully elucidated.Herein,single-domain CoFe_(2)O_(4) catalysts with tunable oxygen vacancies(CFO-V_(O)) were synthesized to probe how V_(O) mediates magnetism and OER activity under magnetic field.The introduction of V_(O) can simultaneously modulate saturation magnetization(M_(s)) and coercivity(H_(c)),where the increased M_(s) dominates the magnetic field-enhanced OER activity.Under a 14,000 G magnetic field,the optimized CFO-V_(O) exhibits up to 16.1 % reduction in overpotential and 365 % enhancement in magnetocurrent(MC).Electrochemical analyses and post-OER characterization reveal that the magnetic field synergistically improves OER kinetics through lattice distortion induction,magnetohydrodynamic effect,and spin charge transfer effect.Importantly,the magnetic field promotes additional Co^(3+) generation to compensate for charge imbalance caused by V_(O) filling,maintaining dynamic equilibrium of V_(O) and effective reactant adsorption-conversion processes.This work unveils the synergistic mechanism of V_(O) and magnetic parameters for enhancing OER performance under the magnetic field,providing new insights into the design of high-efficiency spinregulated OER catalysts. 展开更多
关键词 Spinel oxide Oxygen vacancy magnetic field magnetic property Oxygen evolution reaction
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Effects of Mn doping on the reactivity,elastic,and magnetic properties ofα-Fe_(2)O_(3)based on DFT calculation
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作者 WANG Peng DONG Changqing +4 位作者 XUE Junjie GAO Qi HU Xiaoying ZHANG Junjiao ZHAO Jie 《燃料化学学报(中英文)》 北大核心 2026年第2期140-152,共13页
Oxygen carriers play a fundamental role in chemical looping combustion(CLC).Iron-based carriers have been extensively investigated owing to their abundance and environmentally friendly.However,the reactivity and separ... Oxygen carriers play a fundamental role in chemical looping combustion(CLC).Iron-based carriers have been extensively investigated owing to their abundance and environmentally friendly.However,the reactivity and separability of iron-based carriers require further enhancement.This study investigates the effect of the concentration of Mn doping on reactivity,elastic properties and magnetic properties based on density functional theory(DFT)calculations.Theoretical results demonstrate that Mn doping effectively enhances reactivity by reducing the oxygen vacancy formation energy(E_(vac))from 2.33 to 0.87 eV.However,Mn doping introduces HV/EV Ms lattice distortions that deteriorate elastic properties,thereby reducing wear resistance,as evidenced by a 54.54%decrease in the hardness-to-Young's modulus ratio(H_(v)/E_(v))forα-Fe_(2)O_(3)and an 83.33%reduction for Fe_(3)O_(4).Furthermore,Mn doping also modifies magnetic properties.The maximum of saturation magnetization(M_(s))of Fe_(3)O_(4)reaches 121.02 emu/g at 33.33%Mn doping concentration.Finally,systematic evaluation identifies 33.33%as the optimal Mn doping concentration,achieving a balance in enhanced reactivity,superior magnetic performance,and retained elastic stability. 展开更多
关键词 oxygen carrier Mn-dopedα-Fe_(2)O_(3) REACTIVITY elastic properties magnetic properties
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Coordination Thermodynamic Control of Magnetic Domain Configuration Evolution toward Low‑Frequency Electromagnetic Attenuation
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作者 Tong Huang Dan Wang +9 位作者 Xue He Zhaobo Feng Zhiqiang Xiong Yuqi Luo Yuhui Peng Guangsheng Luo Xuliang Nie Mingyue Yuan Chongbo Liu Renchao Che 《Nano-Micro Letters》 2026年第3期860-875,共16页
The precise tuning of magnetic nanoparticle size and magnetic domains,thereby shaping magnetic properties.However,the dynamic evolution mechanisms of magnetic domain configurations in relation to electromagnetic(EM)at... The precise tuning of magnetic nanoparticle size and magnetic domains,thereby shaping magnetic properties.However,the dynamic evolution mechanisms of magnetic domain configurations in relation to electromagnetic(EM)attenuation behavior remain poorly understood.To address this gap,a thermodynamically controlled periodic coordination strategy is proposed to achieve precise modulation of magnetic nanoparticle spacing.This approach unveils the evolution of magnetic domain configurations,progressing from individual to coupled and ultimately to crosslinked domain configurations.A unique magnetic coupling phenomenon surpasses the Snoek limit in low-frequency range,which is observed through micromagnetic simulation.The crosslinked magnetic configuration achieves effective low-frequency EM wave absorption at 3.68 GHz,encompassing nearly the entire C-band.This exceptional magnetic interaction significantly enhances radar camouflage and thermal insulation properties.Additionally,a robust gradient metamaterial design extends coverage across the full band(2–40 GHz),effectively mitigating the impact of EM pollution on human health and environment.This comprehensive study elucidates the evolution mechanisms of magnetic domain configurations,addresses gaps in dynamic magnetic modulation,and provides novel insights for the development of high-performance,low-frequency EM wave absorption materials. 展开更多
关键词 Thermodynamically controlled coordination strategy magnetic domain configuration Low-frequency electromagnetic wave absorption Electrical/magnetic coupling MULTIFUNCTION
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Cerebrospinal fluid as a therapeutic medium for magnetic nanoparticle transport in brain cancer hyperthermia
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作者 Essam T Abdelwahab Ahmed A Elsawy +1 位作者 Abdallah A Henedy Sara I Abdelsalam 《Chinese Physics B》 2026年第2期475-490,共16页
Neuronanomedicine is a promising interdisciplinary field combining two critical fields,neuroscience and nanotechnology.This study focuses on the engineering of magnetized nanoparticles(MNPs)in diagnosing and treating ... Neuronanomedicine is a promising interdisciplinary field combining two critical fields,neuroscience and nanotechnology.This study focuses on the engineering of magnetized nanoparticles(MNPs)in diagnosing and treating neurological disorders and brain cancer.Additionally,this mechanism enhances the effectiveness of magnetic-guided drug delivery.The alternating magnetic field is applied to control the directions of the MNPs to target the tumor cells.This study approaches the radiotherapy techniques of magnetic hyperthermia therapy(MHT),wherein the thermal radiative heat transfer effect is applied to achieve homogenous heating to destroy cancer cells.MNPs are injected through the cerebrospinal fluid(CSF)transport in the glymphatic system.The elastic properties of the cerebral arteries cause peristaltic propulsion for the resulting nanofluid.Therefore,the effective Maxwell model for the nanofluid thermal conductivity is selected.The nanofluid governing equations are solved using the perturbation technique under small wavelength number and long wavelength approximation with small Reynolds number.Additionally,the effects of thermal slip and elastic properties boundary conditions are incorporated.The graphical results for the streamwise velocity,pressure,and temperature distributions are plotted using MATLAB package considering the different effects of the magnetic flux intensity,thermal radiation parameter,thermal slipping at boundaries,elastic wall properties,and nanoparticle concentration.The results demonstrate the strong impact of the magnetic field and radiation heating in terms of enhancing the nanofluid CSF flow behavior and destroying cancer. 展开更多
关键词 peristaltic flow thermal radiation magnetic field NANOFLUID perturbation technique
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Ultrasound/magnetic field dual-responsive Fe_(3)O_(4)/glucose oxidase catalytic microbubbles for enhanced bacterial biofilm elimination
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作者 Chi Zhang Dou Wang +6 位作者 Liang Lu Feng-Jiao Xu Fan-Sen Xu Xuan Wu Xiao-Xiao Xu Xiao Li Li-Hui Yuwen 《Biomedical Engineering Communications》 2026年第1期4-12,共9页
Background:The bacterial biofilm poses a significant challenge to traditional antibiotic therapy.There is a great need to develop novel antibiofilm agents combined with biofilm disrupting and bacteria-killing without ... Background:The bacterial biofilm poses a significant challenge to traditional antibiotic therapy.There is a great need to develop novel antibiofilm agents combined with biofilm disrupting and bacteria-killing without the dependence of antibiotic.Methods:Herein,we prepared ultrasound/magnetic field-responsive ferroferric oxide nanoparticles(Fe_(3)O_(4))/glucose oxidase microbubbles(FGMB)to form a cascade catalytic system for effective removing methicillin-resistant Staphylococcus aureus biofilms.FGMB were prepared through interfacial self-assembly of Fe_(3)O_(4) nanoparticles(NPs)and glucose oxidase(GOx)at the gas-liquid interface stabilized by surfactants.Under ultrasound/magnetic field stimulation,FGMB disrupted biofilm architecture through microbubble collapse-induced microjets and magnetically driven displacement.Simultaneously,ultrasound-triggered rupture of FGMB released GOx and Fe_(3)O_(4) NPs.Glucose can be oxidized by GOx to generate gluconic acid and hydrogen peroxide which was subsequently catalyzed into hydroxyl radicals by Fe_(3)O_(4) NPs,enabling chemical eradication of biofilm-embedded bacteria.Results:Optical microscopy images demonstrated that FGMB have spherical structure with average size of approximately 17μm.FGMB showed a 65.4%decrease in methicillin-resistant Staphylococcus aureus biofilm biomass and 1.1 log bacterial inactivation efficiency(91.2%),suggesting effective biofilm elimination.In vitro experimental results also indicate that FGMB have good biocompatibility.Conclusion:This antibiofilm strategy integrated dual modes of physical biofilm disruption with chemical bacteria-killing shows great potential as a versatile,non-resistant strategy for bacterial biofilm elimination. 展开更多
关键词 bacterial biofilm ULTRASOUND magnetic field catalytic microbubbles mechanical disruption chemical degradation
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Water-soluble Polymer Ligand Mediated Synthesis of Superparamagnetic Iron Oxide Nanoparticles for Magnetic Resonance Imaging
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作者 Ping-Ting Gong Jiao-Jiao Guo +7 位作者 Chang Gao Wei-Tao Yang Chun-Sheng Xiao Yi Xu Yue Yao Irshad Hussain Wen Fan Wei Yan 《Chinese Journal of Polymer Science》 2026年第2期407-415,I0011,共10页
Magnetic resonance imaging(MRI)is one of the most widely used diagnostic techniques.Iron oxide nanoparticles,as a promising kind of contrast agents,have attracted intense research interest due to their low toxicity an... Magnetic resonance imaging(MRI)is one of the most widely used diagnostic techniques.Iron oxide nanoparticles,as a promising kind of contrast agents,have attracted intense research interest due to their low toxicity and superparamagnetism.However,it is still a great challenge to prepare ideal iron oxide based contrast agents with high uniformity,excellent water solubility and biocompatibility.In this paper,a novel water-soluble polymer ligand pentaerythritol tetrakis 3-mercaptopropionate-poly(N-vinyl-2-pyrrolidone)(PTMP-PVP)was used as a capping reagent to prepare iron oxide nanoparticles MIONs@PTMP-PVP through one-step co-precipitation of iron precursors in aqueous solution at 100℃.The obtained nanoparticles MIONs@PTMP-PVP had a small size and narrow size distribution,and they were found to be biocompatible as determined through CCK-8 assay and histology analysis.In vivo MRI study demonstrated that the obtained MIONs@PTMP-PVP can be potentially used as an effective T_(2)-weighted MRI contrast agent. 展开更多
关键词 Iron oxide nanoparticles Water-soluble polymer ligand magnetic resonance imaging
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Spatiotemporal heterogeneity of magnetic enhancement mechanisms in aeolian deposits on the southern Tibetan Plateau:Implications for paleoclimatic reconstruction in mountainbasin systems
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作者 WANG Haoyu YANG Junhuai +9 位作者 QU Wenxi WANG Linkai ZHANG Canyi LIU Xin TANG Jinmeng GAO Fuyuan CHEN Zixuan WANG Shuyuan FAN Yijiao WU Duo 《Journal of Geographical Sciences》 2026年第1期177-198,共22页
Aeolian deposits across the Yarlung Zangbo River Basin on the southern Tibetan Plateau record the landscape and atmospheric evolution of Earth's Third Pole.The complex mountain-basin system exhibits nonlinear resp... Aeolian deposits across the Yarlung Zangbo River Basin on the southern Tibetan Plateau record the landscape and atmospheric evolution of Earth's Third Pole.The complex mountain-basin system exhibits nonlinear responses to climate forcing,complicating the interpretation of its high-altitude environmental dynamics.Investigating the magnetic enhancement mechanism of aeolian deposits offers an opportunity to decipher climate signals.Our analysis of three aeolian sections from the basin indicates that magnetic minerals are predominantly low-coercivity ferrimagnetic minerals,and grain sizes fine from upper to lower reaches due to climate shifts from arid to humid.Magnetic enhancement in the upper reaches primarily originates from dust input,while dust input and pedogenesis contribute variably over time in the middle and lower reaches.Similar complex patterns occur in the Ili basin,a mountain-basin system in northwestern China.They differ from the Chinese Loess Plateau,where long-distance-transported dust is well-mixed and the pedogenic enhancement model is applied,and desert peripheries where short-distance dust is transported and the dust input model is applied.We summarize the magnetic enhancement mechanisms in various settings and offer a new framework for applying magnetic techniques in paleoclimate reconstruction within global mountain-basin systems,which highlights the need for caution in interpreting their magnetic susceptibility records. 展开更多
关键词 HOLOCENE aeolian deposits magnetic properties climate change Yarlung Zangbo River Basin
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Magnetic fabric of the late Miocene extrusive rocks of the Combia Volcanic Province:Tectonic implications for the northern Andes
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作者 Victor A.Piedrahita Martin Chadima +3 位作者 Jackeline Ramírez Alejandra Tabares Maria I.Marín-Cerón JinHua Li 《Earth and Planetary Physics》 2026年第1期44-56,共13页
The accretion of the Panama-ChocóBlock to the South American Plate partially drove the geological setting of the northern Andes.This event occurred in different collisional stages that are recorded in Oligocene-m... The accretion of the Panama-ChocóBlock to the South American Plate partially drove the geological setting of the northern Andes.This event occurred in different collisional stages that are recorded in Oligocene-middle Miocene deformed rocks of the inter-Andean valley between the Western and Central Cordilleras of Colombia.However,uncertainty remains about the age of the latest accretionary phases of the Panama-ChocóBlock.Poorly studied late Miocene volcanic rocks within the northern inter-Andean valley may provide key information to constrain the temporality of that final collision.Here,we study the deformational features of the~12-6 Ma extrusive rocks of the Combia Volcanic Province located in the northwestern Andes(Colombia).We present anisotropy of magnetic susceptibility(AMS)data for pyroclastic and volcanic rocks within the AmagáBasin,an inter-Andean depression with Oligocene-middle Miocene sedimentary rocks that recorded NW-SE compression and NE-SW simple shear caused by the Panama-ChocóBlock collision.We identified that the magnetic fabrics of the extrusive rocks of the Combia Volcanic Province reveal flow directions that indicate the occurrence of ancient volcanoes in the central axis of the AmagáBasin.Some of these fabrics do not contain any deformational features,whereas others record the same structural regime as the Oligocene-middle Miocene sedimentary rocks.We infer that variations in the intensity of the deformation promoted late Miocene local fault reactivations that,in contrast to the Oligocene-middle Miocene deformational events,did not affect the entire AmagáBasin.Age differences among the studied sections can also explain the different deformational patterns identified in the basin.Both interpretations suggest that the most significant collisional events of the Panama-ChocóBlock occurred in the Oligocene-middle Miocene,whereas the formation of the Combia Volcanic Province may have either followed or coincided with the latest stages of the accretion. 展开更多
关键词 Combia Volcanic Province Panama-ChocóBlock magnetic fabric deformation flow direction
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Healthcare professionals’perspectives on disclosure of diagnosis and related issues in childhood cancer:A mixed methods systematic review
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作者 Run Xie Xiaoyan Huang +4 位作者 Yiran Du Ying Gu Qiongfang Kang Hongsheng Wang Daqian Zhu 《International Journal of Nursing Sciences》 2026年第1期96-104,I0006,共10页
Objectives This review aimed to systematically synthesize the available research on the disclosure of diagnosis and related issues in childhood cancer from the perspectives of healthcare professionals,with the goal of... Objectives This review aimed to systematically synthesize the available research on the disclosure of diagnosis and related issues in childhood cancer from the perspectives of healthcare professionals,with the goal of informing the optimization of disclosure processes and meeting the communication needs of affected families.Methods In accordance with the Joanna Briggs Institute(JBI)methodology for mixed methods systematic reviews,the convergent segregated approach was used in this review.Articles were retrieved from 11 databases,including PubMed,Web of Science,CINAHL,CENTRAL,Embase,Ovid/Medline,PsycINFO,PsycArticles,Scopus,ERIC,and China National Knowledge Infrastructure(CNKI).The quality of the selected articles was assessed using the Mixed Method Appraisal Tool(MMAT).The review protocol was registered on PROSPERO(CRD42024542746).Results A total of 21 studies from 10 countries were included.Their methodological quality was generally medium to high,with MMAT scores ranging from 60%to 100%.The synthesis yielded three core themes:1)the spectrum of professional and societal attitudes toward disclosure;2)the dynamic practices of navigating disclosure amid uncertainty,including timing and environment,stakeholders,and content of disclosure;and 3)factors influencing disclosure,including children’s,parental,healthcare professionals’,and socio-cultural factors.Conclusions This review synthesized the perspectives and experiences of healthcare professionals regarding disclosure in childhood cancer,highlighting the complexity and multidimensional nature of this process in clinical practice.Future research should further investigate the experiences and needs of children and their parents,explore cultural variations in disclosure practices,develop context-appropriate assessment tools,and construct multidimensional intervention strategies to enhance the humanistic care and professional effectiveness of the disclosure process. 展开更多
关键词 Communication CANCER DISCLOSURE Healthcare professionals Mixed methods PEDIATRIC Systematic review
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Multiscale Single-Phase Flow Mechanisms of Shale Oil Revealed by High-Pressure Nuclear Magnetic Resonance Experiments
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作者 Maolei Cui Zengmin Lun +2 位作者 Jie Zhang Jun Niu Pufu Xiao 《Fluid Dynamics & Materials Processing》 2026年第2期253-264,共12页
To clarify fluid flow mechanisms and establish effective development conditions in continental shale oil reservoirs,a high-temperature,high-pressure steady-state flow system integrated with nuclear magnetic resonance(... To clarify fluid flow mechanisms and establish effective development conditions in continental shale oil reservoirs,a high-temperature,high-pressure steady-state flow system integrated with nuclear magnetic resonance(NMR)technology has been developed.The apparatus combines sample evacuation,rapid pressurization and saturation,and controlled displacement,enabling systematic investigation of single-phase shale oil flow under representative reservoir conditions.Related experiments allow proper quantification of the activation thresholds and relative contributions of different pore types to flow.A movable fluid index(MFI),defined using dual T_(2) cutoff values,is introduced accordingly and linked to key flow parameters.The results reveal distinct multi-scale characteristics of single-phase shale oil transport,namely micro-scale graded displacement and macro-scale segmented nonlinear behavior.As the injection-production pressure difference increases,flow pathways are activated progressively,beginning with fractures,followed by large and then smaller macropores,leading to a pronounced enhancement in apparent permeability.Although mesopores and micropores contribute little to direct flow,their indirect influence becomes increasingly important,and apparent permeability gradually approaches a stable limit at higher pressure difference.It is also shown that the MFI exhibits a strong negative correlation with the starting pressure gradient and a positive correlation with apparent permeability,providing a rapid and reliable indicator of shale oil flow capacity.Samples containing through-going fractures display consistently higher MFI values and superior flowability compared with those dominated by laminated fractures,highlighting the pivotal role of well-connected fracture networks generated by large-scale hydraulic fracturing in improving shale oil production. 展开更多
关键词 Shale oil laminated fractures steady-state flow Nuclear magnetic Resonance(NMR) nonlinear flow
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