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Microglia in drug addiction:A perspective from neuroimmunopharmacology 被引量:1
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作者 Cong Lin Xiaohui Wang 《Zoological Research》 SCIE CSCD 2024年第3期704-706,共3页
Drug addiction refers to a state of dependence that arises from habitual drug intake and can result in specific withdrawal symptoms upon cessation.The most commonly abused substances include psychostimulants,cannabino... Drug addiction refers to a state of dependence that arises from habitual drug intake and can result in specific withdrawal symptoms upon cessation.The most commonly abused substances include psychostimulants,cannabinoids,and opioids.When drugs are consumed,they stimulate the release of dopamine,a neurotransmitter crucial for the pleasure and reward centers of the brain.With repeated drug use,the brain undergoes various changes,leading to tolerance,dependence,and addiction(Lüscher et al.,2020).The mechanisms involved in drug addiction are highly complex and involve diverse cell types within the brain. 展开更多
关键词 ADDICTION DRUGS INTAKE
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Pluggable multitask diffractive neural networks based on cascaded metasurfaces 被引量:1
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作者 Cong He Dan Zhao +8 位作者 Fei Fan Hongqiang Zhou Xin Li Yao Li Junjie Li Fei Dong Yin-Xiao Miao Yongtian Wang Lingling Huang 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第2期23-31,共9页
Optical neural networks have significant advantages in terms of power consumption,parallelism,and high computing speed,which has intrigued extensive attention in both academic and engineering communities.It has been c... Optical neural networks have significant advantages in terms of power consumption,parallelism,and high computing speed,which has intrigued extensive attention in both academic and engineering communities.It has been considered as one of the powerful tools in promoting the fields of imaging processing and object recognition.However,the existing optical system architecture cannot be reconstructed to the realization of multi-functional artificial intelligence systems simultaneously.To push the development of this issue,we propose the pluggable diffractive neural networks(P-DNN),a general paradigm resorting to the cascaded metasurfaces,which can be applied to recognize various tasks by switching internal plug-ins.As the proof-of-principle,the recognition functions of six types of handwritten digits and six types of fashions are numerical simulated and experimental demonstrated at near-infrared regimes.Encouragingly,the proposed paradigm not only improves the flexibility of the optical neural networks but paves the new route for achieving high-speed,low-power and versatile artificial intelligence systems. 展开更多
关键词 optical neural networks diffractive deep neural networks cascaded metasurfaces
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Effect of trace oxygen on plasma nitriding of titanium foil
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作者 周海涛 熊希雅 +3 位作者 马可欣 罗炳威 罗飞 申承民 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期548-551,共4页
Titanium nitride films are prepared by plasma enhanced chemical vapor deposition method on titanium foil using N_(2) as precursor. In order to evaluate the effect of oxygen on the growth of titanium nitride films, a s... Titanium nitride films are prepared by plasma enhanced chemical vapor deposition method on titanium foil using N_(2) as precursor. In order to evaluate the effect of oxygen on the growth of titanium nitride films, a small amount of O_(2) is introduced into the preparation process. The study indicates that trace O_(2) addition into the reaction chamber gives rise to significant changes on the color and micro-morphology of the foil, featuring dense and long nano-wires. The as-synthesized nanostructures are characterized by various methods and identified as TiN, Ti_(2) N, and TiO_(2) respectively. Moreover, the experiment results show that oxide nanowire has a high degree of crystallinity and the nitrides present specific orientation relationships with the titanium matrix. 展开更多
关键词 NITRIDE OXIDE NANOSTRUCTURE CRYSTALLINE plasma-enhanced chemical vapor deposition system(PECVD)
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Strong metal-support interactions between highly dispersed Cu^(+) species and ceria via mix-MOF pyrolysis toward promoted water-gas shift reaction
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作者 Xiao-Chen Sun Xing-Chi Li +7 位作者 Ze-Wei Xie Chen-Yue Yuan De-Jiu Wang Qian Zhang Xiao-Yu Guo Hao Dong Hai-Chao Liu Ya-Wen Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期475-483,共9页
The modulation of metal-support interfacial interaction is significant but challenging in the design of high-efficiency and high-stability supported catalysts.Here,we report a synthetic strategy to upgrade Cu-CeO_(2)i... The modulation of metal-support interfacial interaction is significant but challenging in the design of high-efficiency and high-stability supported catalysts.Here,we report a synthetic strategy to upgrade Cu-CeO_(2)interfacial interaction by the pyrolysis of mixed metal-organic framework(MOF)structure.The obtained highly dispersed Cu/CeO_(2)-MOF catalyst via this strategy was used to catalyze water-gas shift reaction(WGSR),which exhibited high activity of 40.5μmolCOgcat^(-1).s^(-1)at 300℃and high stability of about 120 h.Based on comprehensive studies of electronic structure,pyrolysis strategy has significant effect on enhancing metal-support interaction and then stabilizing interfacial Cu^(+)species under reaction conditions.Abundant Cu^(+)species and generated oxygen vacancies over Cu/CeO_(2)-MOF catalyst played a key role in CO molecule activation and H2O molecule dissociation,respectively.Both collaborated closely and then promoted WGSR catalytic performance in comparison with traditio nal supported catalysts.This study shall offer a robust approach to harvest highly dispersed catalysts with finely-tuned metal-support interactions for stabilizing the most interfacial active metal species in diverse heterogeneous catalytic reactions. 展开更多
关键词 Cu-based catalyst MOF derivative Water-gas shift reaction Metal-support interaction
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High energy density in ultra-thick and flexible electrodes enabled by designed conductive agent/binder composite
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作者 Xiaoyu Shen Hailong Yu +6 位作者 Liubin Ben Wenwu Zhao Qiyu Wang Guanjun Cen Ronghan Qiao Yida Wu Xuejie Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期133-143,I0005,共12页
Thick electrodes can increase incorporation of active electrode materials by diminishing the proportion of inactive constituents,improving the overall energy density of batteries.However,thick electrodes fabricated us... Thick electrodes can increase incorporation of active electrode materials by diminishing the proportion of inactive constituents,improving the overall energy density of batteries.However,thick electrodes fabricated using the conventional slurry casting approach frequently exhibit an exacerbated accumulation of carbon additives and binders on their surfaces,invariably leading to compromised electrochemical properties.In this study,we introduce a designed conductive agent/binder composite synthesized from carbon nanotube and polytetrafluoroethylene.This agent/binder composite facilitates production of dry-process-prepared ultra-thick electrodes endowed with a three-dimensional and uniformly distributed percolative architecture,ensuring superior electronic conductivity and remarkable mechanical resilience.Using this approach,ultra-thick LiCoO_(2)(LCO) electrodes demonstrated superior cycling performance and rate capabilities,registering an impressive loading capacity of up to 101.4 mg/cm^(2),signifying a 242% increase in battery energy density.In another analytical endeavor,time-of-flight secondary ion mass spectroscopy was used to clarify the distribution of cathode electrolyte interphase(CEI) in cycled LCO electrodes.The results provide unprecedented evidence explaining the intricate correlation between CEI generation and carbon distribution,highlighting the intrinsic advantages of the proposed dry-process approach in fine-tu ning the CEI,with excellent cycling performance in batteries equipped with ultra-thick electrodes. 展开更多
关键词 Conductive agent/binder composite Dry process Ultra-thick electrodes High energy density CEI reconstruction ToF-SIMS
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Databases of 2D material-substrate interfaces and 2D charged building blocks
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作者 邓俊 潘金波 杜世萱 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期34-38,共5页
Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new mater... Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new materials in this respect.In van der Waals(vdW)layered materials,these building blocks are charge neutral and can be isolated from their bulk phase(top-down),but usually grow on substrate.In ionic layered materials,they are charged and usually cannot exist independently but can serve as motifs to construct new materials(bottom-up).In this paper,we introduce our recently constructed databases for 2D material-substrate interface(2DMSI),and 2D charged building blocks.For 2DMSI database,we systematically build a workflow to predict appropriate substrates and their geometries at substrates,and construct the 2DMSI database.For the 2D charged building block database,1208 entries from bulk material database are identified.Information of crystal structure,valence state,source,dimension and so on is provided for each entry with a json format.We also show its application in designing and searching for new functional layered materials.The 2DMSI database,building block database,and designed layered materials are available in Science Data Bank at https://doi.org/10.57760/sciencedb.j00113.00188. 展开更多
关键词 2D material-substrate interfaces charged building block database functional-oriented materials design layered materials density functional theory
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Quantum synchronization with correlated baths
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作者 李磊 王春辉 +2 位作者 尹洪浩 王如泉 刘伍明 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期152-157,共6页
We study quantum synchronization under the nonequilibrium reservoirs.We consider a two-qubit XXZ chain coupled independently to their own reservoirs modeled by the collisional model.Two reservoir particles,initially p... We study quantum synchronization under the nonequilibrium reservoirs.We consider a two-qubit XXZ chain coupled independently to their own reservoirs modeled by the collisional model.Two reservoir particles,initially prepared in a thermal state or a state with coherence,are correlated through a unitary transformation and afterward interact locally with the two quantum subsystems.We study the quantum effect of reservoir on synchronous dynamics of system.By preparing different reservoir initial states or manipulating the reservoir particles coupling and the temperature gradient,we find that quantum entanglement of reservoir is the key to control quantum synchronization of system qubits. 展开更多
关键词 quantum synchronization ENTANGLEMENT quantum coherence nonequilibrium reservoir
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Unveiling the in-plane anisotropic dielectric waveguide modes in α-MoO_(3) flakes
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作者 廖莹 陈佳宁 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期631-636,共6页
The unique in-plane and out-of-plane anisotropy of α-MoO_(3) has attracted considerable interest with regard to potential optoelectronic applications. However, most research has focused on the mid-infrared spectrum, ... The unique in-plane and out-of-plane anisotropy of α-MoO_(3) has attracted considerable interest with regard to potential optoelectronic applications. However, most research has focused on the mid-infrared spectrum, leaving its properties and applications in the visible and near-infrared light spectrum less explored. This study advances the understanding of waveguiding properties of α-MoO_(3) by near-field imaging of the waveguide modes along the [100] and [001] directions of α-MoO_(3) flakes at 633 nm and 785 nm. We investigate the effects of flake thickness and documented the modes' dispersion relationships, which is crucial for tailoring the optical responses of α-MoO_(3) in device applications. Our findings enhance the field of research into α-MoO_(3), highlighting its utility in fabricating next-generation optoelectronic devices due to its unique optically anisotropic waveguide. 展开更多
关键词 WAVEGUIDE anisotropic materials near-field imaging van der Waals materials
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Absence of BCS–BEC crossover in FeSe_(0.45)Te_(0.55) superconductor
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作者 贾俊杰 谷亚东 +21 位作者 殷超辉 束英杰 陈逸雯 史聚民 张杏 陈浩 苗泰民 任晓琳 梁波 朱文培 蔡能 张丰丰 张申金 杨峰 王志敏 彭钦军 许祖彦 毛寒青 刘国东 任治安 赵林 周兴江 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期79-85,共7页
In iron-based superconductor Fe(Se,Te), a flat band-like feature near the Fermi level was observed around the Brillouin zone center in the superconducting state. It is under debate whether this is the evidence on the ... In iron-based superconductor Fe(Se,Te), a flat band-like feature near the Fermi level was observed around the Brillouin zone center in the superconducting state. It is under debate whether this is the evidence on the presence of the BCS–BEC[Bardeen–Cooper–Schrieffer(BCS), Bose–Einstein condensation(BEC)] crossover in the superconductor. High-resolution laser-based angle-resolved photoemission measurements are carried out on high quality single crystals of FeSe_(0.45)Te_(0.55) superconductor to address the issue. By employing different polarization geometries, we have resolved and isolated the dyz band and the topological surface band, making it possible to study their superconducting behaviors separately. The dyz band alone does not form a flat band-like feature in the superconducting state and the measured dispersion can be well described by the BCS picture. We find that the flat band-like feature is formed from the combination of the dyz band and the topological surface state band in the superconducting state. These results reveal the origin of the flat band-like feature and rule out the presence of BCS-BEC crossover in Fe(Se,Te) superconductor. 展开更多
关键词 FeSe_(0.45)Te_(0.55) ARPES electronic structure superconducting gap BCS–BEC crossover
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Preparing highly entangled states of nanodiamond rotation and NV center spin
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作者 李文亮 周端陆 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期144-151,共8页
A nanodiamond with an embedded nitrogen-vacancy(NV)center is one of the experimental systems that can be coherently manipulated within current technologies.Entanglement between NV center electron spin and mechanical r... A nanodiamond with an embedded nitrogen-vacancy(NV)center is one of the experimental systems that can be coherently manipulated within current technologies.Entanglement between NV center electron spin and mechanical rotation of the nanodiamond plays a fundamental role in building a quantum network connecting these microscopic and mesoscopic degrees of motions.Here we present a protocol to asymptotically prepare a highly entangled state of the total quantum angular momentum and electron spin by adiabatically boosting the external magnetic field. 展开更多
关键词 NANODIAMOND NV center ENTANGLEMENT
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FL-Online:An x-ray crystallographic web-server for atomic-scale structure analysis of biomolecule
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作者 王宾堂 牛彤欣 +1 位作者 范海福 丁玮 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期37-42,共6页
FL-Online(http://fanlab.ac.cn) is an out-of-box modern web service featuring a user-friendly interface and simplified parameters, providing academic users with access to a series of online programs for biomolecular cr... FL-Online(http://fanlab.ac.cn) is an out-of-box modern web service featuring a user-friendly interface and simplified parameters, providing academic users with access to a series of online programs for biomolecular crystallography, including SAPI-online, OASIS-online, C-IPCAS-online and a series of upcoming software releases. Meanwhile, it is a highly scalable and maintainable web application framework that provides a powerful and flexible solution for academic web development needs. All the codes are open-source under MIT licenses in GitHub. 展开更多
关键词 graphical web service OASIS IPCAS direct methods protein crystallography
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Synthesis and Modulation of Low-Dimensional Transition Metal Chalcogenide Materials via Atomic Substitution
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作者 Xuan Wang Akang Chen +3 位作者 XinLei Wu Jiatao Zhang Jichen Dong Leining Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期49-94,共46页
In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk counterpart... In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk counterparts.The controllable synthesis and manipulation of these materials are crucial for tailoring their properties and unlocking their full potential in various applications.In this context,the atomic substitution method has emerged as a favorable approach.It involves the replacement of specific atoms within TMC structures with other elements and possesses the capability to regulate the compositions finely,crystal structures,and inherent properties of the resulting materials.In this review,we present a comprehensive overview on various strategies of atomic substitution employed in the synthesis of zero-dimensional,one-dimensional and two-dimensional TMC materials.The effects of substituting elements,substitution ratios,and substitution positions on the structures and morphologies of resulting material are discussed.The enhanced electrocatalytic performance and photovoltaic properties of the obtained materials are also provided,emphasizing the role of atomic substitution in achieving these advancements.Finally,challenges and future prospects in the field of atomic substitution for fabricating low-dimensional TMC materials are summarized. 展开更多
关键词 Transition metal chalcogenides Atomic substitution Ion exchange Low-dimensional materials Controllable synthesis
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Electronic transport evolution across the successive structural transitions in Ni_(50-x)Fe_xTi_(50) shape memory alloys
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作者 何萍 杨金颖 +3 位作者 任秋飒 王彬彬 吴光恒 刘恩克 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期529-536,共8页
TiNi-based shape memory alloys have been extensively investigated due to their significant applications,but a comprehensive understanding of the evolution of electronic structure and electrical transport in a system w... TiNi-based shape memory alloys have been extensively investigated due to their significant applications,but a comprehensive understanding of the evolution of electronic structure and electrical transport in a system with martensitic transformations(MT) is still lacking.In this work,we focused on the electronic transport behavior of three phases in Ni_(50-x)Fe_xTi_(50)across the MT.A phase diagram of Ni_(50-x)Fe_xTi_(50) was established based on x-ray diffraction,calorimetric,magnetic,and electrical measurements.To reveal the driving force of MT,phonon softening was revealed using first-principles calculations.Notably,the transverse and longitudinal transport behavior changed significantly across the phase transition,which can be attributed to the reconstruction of electronic structures.This work promotes the understanding of phase transitions and demonstrates the sensitivity of electron transport to phase transition. 展开更多
关键词 martensitic transformation electronic behavior transport properties first-principles calculations
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Maskless fabrication of quasi-omnidirectional V-groove solar cells using an alkaline solution-based method
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作者 陈兴谦 王燕 +6 位作者 陈伟 刘尧平 邢国光 冯博文 李昊臻 孙纵横 杜小龙 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期236-242,共7页
Silicon passivated emitter and rear contact(PERC) solar cells with V-groove texture were fabricated using maskless alkaline solution etching with in-house developed additive. Compared with the traditional pyramid text... Silicon passivated emitter and rear contact(PERC) solar cells with V-groove texture were fabricated using maskless alkaline solution etching with in-house developed additive. Compared with the traditional pyramid texture, the V-groove texture possesses superior effective minority carrier lifetime, enhanced p–n junction quality and better applied filling factor(FF). In addition, a V-groove texture can greatly reduce the shading area and edge damage of front Ag electrodes when the V-groove direction is parallel to the gridline electrodes. Due to these factors, the V-groove solar cells have a higher efficiency(21.78%) than pyramid solar cells(21.62%). Interestingly, external quantum efficiency(EQE) and reflectance of the V-groove solar cells exhibit a slight decrease when the incident light angle(θ) is increased from 0° to 75°, which confirms the excellent quasi omnidirectionality of the V-groove solar cells. The proposed V-groove solar cell design shows a 2.84% relative enhancement of energy output over traditional pyramid solar cells. 展开更多
关键词 V-groove alkaline etching quasi omnidirectionality silicon solar cell
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Ultrathin Limit on the Anisotropic Superconductivity of Single-Layered Cuprate Films
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作者 冉峰 陈潘 +5 位作者 李丁艺 熊沛雨 樊子鑫 凌浩铭 梁艳 张坚地 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第2期94-101,共8页
Exploring dimensionality effects on cuprates is important for understanding the nature of high-temperature superconductivity.By atomically layer-by-layer growth with oxide molecular beam epitaxy,we demonstrate that La... Exploring dimensionality effects on cuprates is important for understanding the nature of high-temperature superconductivity.By atomically layer-by-layer growth with oxide molecular beam epitaxy,we demonstrate that La_(2−x)Sr_(x)CuO_(4)(x=0.15)thin films remain superconducting down to 2 unit cells of thickness but quickly reach the maximum superconducting transition temperature at and above 4 unit cells.By fitting the critical magnetic field(μ0H_(c2)),we show that the anisotropy of the film’s superconductivity increases with decreasing film thickness,indicating that the superconductivity of the film gradually evolves from weak three-to two-dimensional character.These results are helpful to gain more insight into the nature of high-temperature superconductivity with dimensionality. 展开更多
关键词 dimensionality FILM evolve
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Tailoring-compensated ferrimagnetic state and anomalous Hall effect in quaternary Mn–Ru–V–Ga Heusler compounds
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作者 梁瑾静 郗学奎 +1 位作者 王文洪 刘永昌 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期595-603,共9页
Cubic Mn_(2)Ru_(x)Ga Heusler compound is a typical example of compensated ferrimagnet with attractive potential for high-density,ultrafast,and low-power spintronic applications.In the form of epitaxial thin films,Mn_(... Cubic Mn_(2)Ru_(x)Ga Heusler compound is a typical example of compensated ferrimagnet with attractive potential for high-density,ultrafast,and low-power spintronic applications.In the form of epitaxial thin films,Mn_(2)Ru_(x)Ga exhibits high spin polarization and high tunability of compensation temperature by freely changing the Ru content x in a broad range(0.3<x<1.0).Herein Mn-Ru-Ga-based polycrystalline bulk buttons prepared by arc melting are systematically studied and it is found that in equilibrium bulk form,the cubic structure is unstable when x<0.75.To overcome this limitation,Mn-Ru-Ga is alloyed with a fourth element V.By adjusting the content of V in the By adjusting the content of V in the Mn_(2)Ru_(0.75)V_(y)Ga and Mn_(2.25-y)Ru_(0.75)V_(y)Ga quaternary systems the magnetic compensation temperature is tuned.Compensation is achieved near 300 K which is confirmed by both the magnetic measurement and anomalous Hall effect measurement.The analyses of the anomalous Hall effect scaling in quaternary Mn-Ru-V-Ga alloy reveal the dominant role of skew scattering,notably that contributed caused by the thermally excited phonons,in contrast to the dominant intrinsic mechanism found in many other 3d ferromagnets and Heusler compounds.It is further shown that the Ga antisites and V content can simultaneously control the residual resistivity ratio(RRR)as well as the relative contribution of phonon and defect to the anomalous Hall effect a"/a0'in Mn-Ru-V-Ga,resulting in a scaling relation a"/a0'∝RRR^(1.8). 展开更多
关键词 compensated ferrimagnet anomalous Hall effect residual resistivity ratio
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Capturing the non-equilibrium state in light–matter–free-electron interactions through ultrafast transmission electron microscopy
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作者 汪文韬 孙帅帅 +5 位作者 李俊 郑丁国 黄思远 田焕芳 杨槐馨 李建奇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期88-101,共14页
Ultrafast transmission electron microscope(UTEM) with the multimodality of time-resolved diffraction, imaging,and spectroscopy provides a unique platform to reveal the fundamental features associated with the interact... Ultrafast transmission electron microscope(UTEM) with the multimodality of time-resolved diffraction, imaging,and spectroscopy provides a unique platform to reveal the fundamental features associated with the interaction between free electrons and matter. In this review, we summarize the principles, instrumentation, and recent developments of the UTEM and its applications in capturing dynamic processes and non-equilibrium transient states. The combination of the transmission electron microscope with a femtosecond laser via the pump–probe method guarantees the high spatiotemporal resolution, allowing the investigation of the transient process in real, reciprocal and energy spaces. Ultrafast structural dynamics can be studied by diffraction and imaging methods, revealing the coherent acoustic phonon generation and photoinduced phase transition process. In the energy dimension, time-resolved electron energy-loss spectroscopy enables the examination of the intrinsic electronic dynamics of materials, while the photon-induced near-field electron microscopy extends the application of the UTEM to the imaging of optical near fields with high real-space resolution. It is noted that light–free-electron interactions have the ability to shape electron wave packets in both longitudinal and transverse directions, showing the potential application in the generation of attosecond electron pulses and vortex electron beams. 展开更多
关键词 ultrafast transmission electron microscopy non-equilibrium structural dynamics photo-induced phase transition free-electron–photon interactions
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FPGA and computer-vision-based atom tracking technology for scanning probe microscopy
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作者 俞风度 刘利 +5 位作者 王肃珂 张新彪 雷乐 黄远志 马瑞松 郇庆 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期76-85,共10页
Atom tracking technology enhanced with innovative algorithms has been implemented in this study,utilizing a comprehensive suite of controllers and software independently developed domestically.Leveraging an on-board f... Atom tracking technology enhanced with innovative algorithms has been implemented in this study,utilizing a comprehensive suite of controllers and software independently developed domestically.Leveraging an on-board field-programmable gate array(FPGA)with a core frequency of 100 MHz,our system facilitates reading and writing operations across 16 channels,performing discrete incremental proportional-integral-derivative(PID)calculations within 3.4 microseconds.Building upon this foundation,gradient and extremum algorithms are further integrated,incorporating circular and spiral scanning modes with a horizontal movement accuracy of 0.38 pm.This integration enhances the real-time performance and significantly increases the accuracy of atom tracking.Atom tracking achieves an equivalent precision of at least 142 pm on a highly oriented pyrolytic graphite(HOPG)surface under room temperature atmospheric conditions.Through applying computer vision and image processing algorithms,atom tracking can be used when scanning a large area.The techniques primarily consist of two algorithms:the region of interest(ROI)-based feature matching algorithm,which achieves 97.92%accuracy,and the feature description-based matching algorithm,with an impressive 99.99%accuracy.Both implementation approaches have been tested for scanner drift measurements,and these technologies are scalable and applicable in various domains of scanning probe microscopy with broad application prospects in the field of nanoengineering. 展开更多
关键词 atom tracking FPGA computer vision drift measurement
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Coevolution of superconductivity and Hall coefficient with anisotropic lattice shrinkage in compressed KCa_(2)Fe_(4)As_(24F_(2)
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作者 韩金宇 洪文山 +9 位作者 蔡树 赵金瑜 郭静 周亚洲 王鹏玉 曹立新 罗会仟 李世亮 吴奇 孙力玲 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期66-70,共5页
The stability of superconductivity in superconductors is widely recognized to be determined by various factors,including charge,spin,orbit,lattice,and other related degrees of freedom.Here,we report our findings on th... The stability of superconductivity in superconductors is widely recognized to be determined by various factors,including charge,spin,orbit,lattice,and other related degrees of freedom.Here,we report our findings on the pressure-induced coevolution of superconductivity and Hall coefficient in KCa_(2)Fe_(4)As_(24F_(2),an iron-based superconductor possessing a hybrid crystal structure combining KFe_(2)As_(2) and CaFeAsF.Our investigation,involving high-pressure resistance,Hall effect and x-ray diffraction(XRD) measurements,allows us to observe the connection of the superconductivity and Hall coefficient with the anisotropic lattice shrinkage.We find that its ambient-pressure tetragonal(T) phase presents a collapse starting at around 18 GPa,where the sign of the Hall coefficient(R_(H)) changes from positive to negative.Upon further compression,both superconducting transition temperature(T_(c)) and R_(H) exhibit a monotonous decrease.At around 41 GPa,the superconductivity is completely suppressed(T_(c)=0),where the parameter a begins to decline again and the Hall coefficient remains nearly unchanged.Our experiment results clearly demonstrate that the pressure-induced anisotropic lattice collapse plays a crucial role in tuning the interplay among multiple degrees of freedom in the superconducting system and,correspondingly,the stability of the superconductivity. 展开更多
关键词 effects of pressure pnictides and chalcogenides transport properties
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Hydrogen generation from NaBH_(4) for portable proton exchange membrane fuel cell
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作者 Bingxue Sun Xingguo Li Jie Zheng 《Materials Reports(Energy)》 EI 2024年第1期69-78,共10页
Sodium borohydride(NaBH_(4)) is considered as the most potential hydrogen storage material for portable proton exchange membrane fuel cells(PEMFC)because of its high theoretical hydrogen capacity.However,the slow and ... Sodium borohydride(NaBH_(4)) is considered as the most potential hydrogen storage material for portable proton exchange membrane fuel cells(PEMFC)because of its high theoretical hydrogen capacity.However,the slow and poor kinetic stability of hydrogen generation from NaBH_(4) hydrolysis limits its application.There are two main factors influencing the kinetics stability of hydrogen generation from NaBH_(4).One factor is that the alkaline byproducts(NaBO_(2)) of the hydrolysis reaction can increase the pH of the solution,thus inhibiting the reaction process.It mainly happens in the NaBH_(4) solution hydrolysis system.Another factor is that the monotonous increase in reaction temperature leads to uncontrollable and unpredictable hydrolysis rates in the solid NaBH_(4) hydrolysis system.This is due to the excess heat generated from this exothermic reaction in the initial reaction of NaBH_(4) hydrolysis.In this perspective,we summarize the latest research progress in hydrogen generation from NaBH_(4) and emphasize the design principles of catalysts for hydrogen generation from NaBH_(4) solution and solid state NaBH_(4).The importance of carbon as catalyst support material for NaBH_(4) hydrolysis is also highlighted. 展开更多
关键词 NaBH_(4)hydrolysis Hydrogen generation CATALYST KINETICS Carbon support materials
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