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Impact of exergames on physical activity and motivation in elementary school students: A follow-up study 被引量:4
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作者 Haichun Sun 《Journal of Sport and Health Science》 SCIE 2013年第3期138-145,共8页
The present study was built upon a previous study on the new generation video game, exergame, in elementary school physical education (PE). The purpose of the study was to examine the effect of exergames on elementa... The present study was built upon a previous study on the new generation video game, exergame, in elementary school physical education (PE). The purpose of the study was to examine the effect of exergames on elementary children's in-class physical activity (PA) intensity levels and perceived situational interest over time. The results indicated that students' situational interest dropped dramatically over two semesters, but their PA intensity increased over time. The results showed that boys and girls were equally active in the exergaming lessons, but boys perceived their gaming experiences more enjoyable than girls did. The findings suggest that exergames may be a possible means to enhance PA in PE. However, whether exergaming is a sustainable way to motivate children in PA is questionable. 展开更多
关键词 Active video game Calorie expenditure GENDER Physical education Situational interest
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Millisecond dynamics of colloidal suspension studied by X-ray photon correlation spectroscopy at the Shanghai Synchrotron Radiation Facility 被引量:1
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作者 Chen-Hui Cui Zi-Mu Zhou +7 位作者 Lin-Feng Wei Song-Lin Li Feng Tian Xiu-Hong Li Zhi Guo Yi-Hui Xu Huai-Dong Jiang Ren-Zhong Tai 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期1-9,共9页
X-ray photon correlation spectroscopy(XPCS)has emerged as a powerful tool for probing the nanoscale dynamics of soft condensed matter and strongly correlated materials owing to its high spatial resolution and penetrat... X-ray photon correlation spectroscopy(XPCS)has emerged as a powerful tool for probing the nanoscale dynamics of soft condensed matter and strongly correlated materials owing to its high spatial resolution and penetration capabilities.This technique requires high brilliance and beam coherence,which are not directly available at modern synchrotron beamlines in China.To facilitate future XPCS experiments,we modified the optical setup of the newly commissioned BL10U1 USAXS beamline at the Shanghai Synchrotron Radiation Facility(SSRF).Subsequently,we performed XPCS measurements on silica suspensions in glycerol,which were opaque owing to their high concentrations.Images were collected using a high frame rate area detector.A comprehensive analysis was performed,yielding correlation functions and several key dynamic parameters.All the results were consistent with the theory of Brownian motion and demonstrated the feasibility of XPCS at SSRF.Finally,by carefully optimizing the setup and analyzing the algorithms,we achieved a time resolution of 2 ms,which enabled the characterization of millisecond dynamics in opaque systems. 展开更多
关键词 XPCS SSRF Silica suspension GLYCEROL Brownian motion Millisecond dynamics
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Carbon enhanced nucleophilicity of Na_(3)V_(2)(PO_(4))_(3):A general approach for dendrite-free zinc metal anodes 被引量:1
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作者 Sijun Wang Lingzi Hu +8 位作者 Xiaohui Li Dan Qiu Shunhang Qiu Qiancheng Zhou Wenwen Deng Xiaoying Lu Ze Yang Ming Qiu Ying Yu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期203-212,共10页
Zincophilic property and high electrical conductivity are both very important parameters to design novel Zn anode for aqueous Zn-ion batteries(AZIBs).However,single material is difficult to exhibit zincophilic propert... Zincophilic property and high electrical conductivity are both very important parameters to design novel Zn anode for aqueous Zn-ion batteries(AZIBs).However,single material is difficult to exhibit zincophilic property and high electrical conductivity at the same time.Herein,originating from theoretical calculation,a zincophilic particle regulation strategy is proposed to address these limitations and carbon coated Na_(3)V_(2)(PO_(4))_(3)is taken as an example to be a protective layer on zinc metal(NVPC@Zn).Na_(3)V_(2)(PO_(4))_(3)(NVP)is a common cathode material for Zn-ion batteries,which is zincophilic.Carbon materials not only offer an electron pathway to help Zn deposition onto NVPC surface,but also enhance the zinc nucleophilicity of Na_(3)V_(2)(PO_(4))_(3).Hence,this hybrid coating layer can tune zinc deposition and resist side reactions such as hydrogen generation and Zn metal corrosion.Experimentally,a symmetrical battery with NVPC@Zn electrode displays highly reversible plating/stripping behavior with a long cycle lifespan over 1800 h at2 mA cm^(-2),much better than carbon and Na_(3)V_(2)(PO_(4))_(3)solely modified Zn electrodes.When the Na_(3)V_(2)(PO_(4))_(3)is replaced with zincophobic Al2O3or zincophilic V2O3,the stability of the modified zinc anodes is also prolonged.This strategy expands the option of zincophilic materials and provides a general and effective way to stabilize the Zn electrode. 展开更多
关键词 Zinc-ion batteries Zinc anode Carbon enhanced nucleophilicity Zincophilic particle regulation
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Li-promoted C_(3)N_(4) catalyst for efficient isomerization of glucose into fructose at 50℃ in water 被引量:1
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作者 Wang Liu Yanfei Zhang +5 位作者 Mengya Sun Xinpeng Zhao Shenggang Li Xinqing Chen Liangshu Zhong Lingzhao Kong 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第9期1419-1426,共8页
Efficient and selective glucose-to-fructose isomerization is a crucial step for production of oxygenated chemicals derived from sugars,which is usually catalyzed by base or Lewis acid heterogeneous catalyst.However,hi... Efficient and selective glucose-to-fructose isomerization is a crucial step for production of oxygenated chemicals derived from sugars,which is usually catalyzed by base or Lewis acid heterogeneous catalyst.However,high yield and selectivity of fructose cannot be simultaneously obtained under mild conditions which hamper the scale of application compared with enzymatic catalysis.Herein,a Li-promoted C_(3)N_(4) catalyst was exploited which afforded an excellent fructose yield(40.3 wt%)and selectivity(99.5%)from glucose in water at 50℃,attributed to the formation of stable Li–N bond to strengthen the basic sites of catalysts.Furthermore,the so-formed N_(6)–Li–H_(2)O active site on Li–C_(3)N_(4) catalyst in aqueous phase changes the local electronic structure and strengthens the deprotonation process during glucose isomerization into fructose.The superior catalytic performance which is comparable to biological pathway suggests promising applications of lithium containing heterogeneous catalyst in biomass refinery. 展开更多
关键词 GLUCOSE FRUCTOSE ISOMERIZATION Li–C_(3)N_(4) Density functional theory calculations
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Lsyn-Esyn,p-δrelation in active galactic nucleus jets and implication for the physical origin of the Lp-Ep,z-Γ_0 relation of gamma-ray bursts
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作者 Xiao-Li Huang En-Wei Liang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2020年第9期201-209,共9页
High energy photon radiations of gamma-ray bursts(GRBs)and active galactic nuclei(AGNs)are dominated by their jet radiations.We examine whether the synchrotron radiations of jets in BL Lacs,flat spectrum radio quasars... High energy photon radiations of gamma-ray bursts(GRBs)and active galactic nuclei(AGNs)are dominated by their jet radiations.We examine whether the synchrotron radiations of jets in BL Lacs,flat spectrum radio quasars(FSRQs),and Narrow Line Seyfert 1 galaxies(NLS1s)follow the relation between the prompt gamma-ray emission and the initial Lorentz factor(Γ0)of GRBs.It is shown that the AGN sample does not agree with the Lp-Ep,z-Γ0 relation of GRBs.In addition,we obtain a tight relation of Lsyn∝Е0.45±0.15δ3.50±0.25 syn,p for FSRQs and NLS1 galaxies,where Lsyn is the luminosity at peak photon energy Esyn,p of the synchrotron radiations.This relation is different from the Lp-Ep,z-Γ0 relation of GRB s.The dependence of Lsyn toδis consistent with the expectation of the Doppler boosting effect for the FSRQs and NLS1 galaxies,but it is not for GRBs.We argue thatΓ0 may be a representative of the kinetic power of the radiating region and the tight Lp-Ep,z-Γ0 relation is shaped by the radiation physics and the jet power together. 展开更多
关键词 gamma-ray burst:general quasars:general BL Lacertae objects:general galaxies:Seyfert stars:jets radiation mechanisms:non-thermal
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Possibilities for the synthesis of superheavy element Z=121 in fusion reactions 被引量:1
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作者 Ming-Hao Zhang Yu-Hai Zhang +3 位作者 Ying Zou Xiu-Xiu Yang Gen Zhang Feng-Shou Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第6期90-100,共11页
Based on the dinuclear system model,the calculated evaporation residue cross sections matched well with the current experimental results.The synthesis of superheavy elements Z=121 was systematically studied through co... Based on the dinuclear system model,the calculated evaporation residue cross sections matched well with the current experimental results.The synthesis of superheavy elements Z=121 was systematically studied through combinations of stable projectiles with Z=21-30 and targets with half-lives exceeding 50 d.The influence of mass asymmetry and isotopic dependence on the projectile and target nuclei was investigated in detail.The reactions^(254)Es(^(46)Ti,3n)^(297)121 and^(252)Es(^(46)Ti,3n)^(295)121 were found to be experimentally feasible for synthesizing superheavy element Z=121,with maximal evaporation residue cross sections of 6.619 and 4.123 fb at 219.9 and 223.9 MeV,respectively. 展开更多
关键词 Superheavy nuclei Dinuclear system model Fusion reaction Evaporation residue cross section
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The Study of the Physical Properties and Energy Sources of Five Luminous Type Ibc Supernovae
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作者 白松瑶 王涛 +3 位作者 王善钦 甘文沛 王浏毅 梁恩维 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第12期34-56,共23页
In this paper,we study five luminous supernovae(LSNe)Ibc(SN 2009ca,ASASSN-15mj,SN 2019omd,SN 2002ued,and SN 2021bmf)whose peak absolute magnitudes M_(peakare)≈-19.5 to-21 mag by fitting their multi-band light curves(... In this paper,we study five luminous supernovae(LSNe)Ibc(SN 2009ca,ASASSN-15mj,SN 2019omd,SN 2002ued,and SN 2021bmf)whose peak absolute magnitudes M_(peakare)≈-19.5 to-21 mag by fitting their multi-band light curves(LCs)with different energy source models.We find that SN 2009ca might be powered by the^(56)Ni model since the required^(56)Ni mass(0.56 M_(⊙))is comparable to those of energetic SNe Ic,while the rest four SNe cannot be accounted for the^(56)Ni model since their derived^(56)Ni masses are(?)1 M_(⊙)or the ratios of the^(56)Ni mass to the ejecta mass are larger than 0.2.This indicates that some LSNe might be powered by^(56)Ni decay,while most of them need additional energy sources.We then use the magnetar plus^(56)Ni model and the fallback plus^(56)Ni model to fit the LCs of the four LSNe that cannot be explained by the^(56)Ni model,finding that the two models can account for the four SNe,and the derived parameters are comparable to those of LSNe or superluminous SNe in the literature,if they were(mainly)powered by magnetars or fallback.We suggest that the magnetar plus^(56)Ni model is more reasonable than the fallback plus^(56)Ni model,since the validity of the fallback plus^(56)Ni model depends on the value of accretion efficiency(η)and favors a largeηvalue,and the magnetar plus^(56)Ni model yields smallerχ^(2)/dof values.It should be pointed out that,however,the fallback plus^(56)Ni model is still a promising model that can account for the four SNe in our sample as well as other LSNe. 展开更多
关键词 Stars-(stars:)supernovae general-stars MAGNETARS
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Bio-Mechanical Investigation on the Physical Resilience of Selected Dominating Shrubs in Semi-Arid Region of Dodoma
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作者 Miraji Hossein Emanuel Jacob 《Journal of Biosciences and Medicines》 2015年第11期136-142,共7页
Physical and mechanical disturbances which interfere with shrubs survival are very common in semi-arid regions. Biomechanical adoptive features of these shrubs therefore account for their competitive and survival poss... Physical and mechanical disturbances which interfere with shrubs survival are very common in semi-arid regions. Biomechanical adoptive features of these shrubs therefore account for their competitive and survival possibilities. Current study investigated physico-ecological properties of five stem cuttings of selected dominating shrubs from Dodoma Municipal that explain their physical resilience. Experimental findings revealed that Acacia nilotica (AN) had the best mechanical adaptations by having the highest values of Young’s modulus of elasticity (E) 332.61 kPa, percentage critical height (PCH) 6.00, whole stem flexibility (WSF) 0.1, flexural stiffness (FS) 7.46 Nm2 as well as angle of deflection (AD). Ziziphus mucronata (ZM) was next to AN, followed by Grewia bicolor (GB) then Acacia tortilis (AT). Boscia grandiflora (BG) had the least mechanical adaptations with the lowest E of 20.94 kPa, PCH of 4.00, WSF of 0.09 as well as FS of 2.90 Nm2. This implied Acacia nilotica having the best ecological adaptations in the semi-arid region while Boscia grandiflora had the least adaptive feature compared to the rest. 展开更多
关键词 Plant ECOLOGY BIOMECHANICAL SHRUBS Stem FLEXIBILITY FLEXURAL Stiffness UDOM
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The Application of SPSS in Statistical Analysis Project-A Study of the Inheritance of Chinese Traditional Shadow Play in Schools
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作者 Wenjie Ye 《Journal of Contemporary Educational Research》 2020年第7期82-86,共5页
Chinese traditional shadow play has been selected into the List of Intangible Cultural Heritage in 2011.Yet,reflecting abundant national cultural values,such traditional art form is degenerating and fading out from pe... Chinese traditional shadow play has been selected into the List of Intangible Cultural Heritage in 2011.Yet,reflecting abundant national cultural values,such traditional art form is degenerating and fading out from people’s sight.As the earliest statistical analysis software,Statistical Package for the Social Science(SPSS)is comprehensive in analyzing and managing statistical data.This study explores the application of SPSS in minimizing the workload of researchers while raising the validity of data in supporting the analysis of the survey data which reflected the inheritance and development of Chinese traditional shadow play in schools. 展开更多
关键词 Statistical Package for the Social Science(SPSS) Statistical Analysis Shadow Play Intangible Cultural Heritage SCHOOLS Inheritance and Development
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Plasma induced dynamic coupling of microscopic factors to collaboratively promote EM losses coupling of transition metal dichalcogenide absorbers 被引量:3
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作者 Jiaming Wen Geng Chen +7 位作者 Shengchong Hui Zijing Li Jijun Yun Xiaomeng Fan Limin Zhang Qian He Xingmin Liu Hongjing Wu 《Advanced Powder Materials》 2024年第3期1-11,共11页
Plasma as the fourth state of matter has attracted great attention for material surface modification,which could induce changes in material microscopic factors,such as defects,phase transitions,crystallinity,and so on... Plasma as the fourth state of matter has attracted great attention for material surface modification,which could induce changes in material microscopic factors,such as defects,phase transitions,crystallinity,and so on.However,the interactions among those microscopic factors and regulation mechanism of macroscopic properties have rarely been investigated.Two-dimensional(2D)transition metal dichalcogenide with tunable structure and phase is one of the most promising electromagnetic wave(EMW)absorbers,which provides a favorable platform for systematically studying the dynamic coupling of its microscopic factors.Herein,we constructed a NaBH_(4) solution-assisted Ar plasma method to modify the 2H-MoS_(2)and 1T-WS_(2)for exploring the regulation mechanism of microscopic factors.For MoS_(2)and WS_(2),NaBH_(4) solution-assisted Ar plasma treatment behaves with different effects on dielectric responses,realizing dynamic coupling of material microscopic factors to collaboratively promote EM losses coupling.Consequently,the MS-D3-0.5(MoS_(2),3 kV voltage,0.5 mol L^(-1)NaBH_(4) solution)displays an optimum effective absorption bandwidth of 8.01 GHz,which is 319.4%more than that of MS-raw sample.This study not only reveals the novel mechanism of plasma induced dynamic coupling of microscopic factors for EMW dissipation,but also presents a new method of plasma-dominated surface modification to optimize the EMW absorption performance. 展开更多
关键词 TMDS Ar plasma Defect Metal single atom Dynamic coupling
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NH_(4)Cl-assisted synthesis of TaON nanoparticle applied to photocatalytic hydrogen and oxygen evolution from water
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作者 Yao Xu Kaiwei Liu +5 位作者 Jifang Zhang Boyang Zhang Jiaming Zhang Ke Shi Haifeng Wang Guijun Ma 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期541-550,共10页
Oxynitride semiconductors are promising photocatalyst materials for visible light-driven water splitting,while the synthesis of well crystalized oxynitride still remains challenge.In present work,narrow-bandgap TaON n... Oxynitride semiconductors are promising photocatalyst materials for visible light-driven water splitting,while the synthesis of well crystalized oxynitride still remains challenge.In present work,narrow-bandgap TaON nanoparticles are synthesized via heating a vacuum-sealed mixture of KTaO_(3),Ta and NH_(4)Cl.This method possesses multiple advantages in terms of lower calcination parameter,higher N conversion efficiency and superior photocatalytic activity in comparison with the traditional thermal ammonolysis using NH_(3) gas as a nitrogen source.Through the analysis of intermediates produced upon the elevation of heating temperature,a gas-solid-phase reaction between TaCl_(5) and Ta_(2)O_(5) is demonstrated as the final step,which is conducive to decreasing thermal energy barrier and accelerating nitridation process.Precise control of preparation conditions,including calcination temperature and duration,allows for the regulation of surface O/N ratio of TaON particles to unity,resulting in optimized photocat-alytic activity.Photoelectrochemical assessment and intensity modulated photocurrent spectroscopy provide convincing evidence for improved charge transfer effciency of photoexcited holes at TaON surface.A Z-scheme overall water splitting is accomplished by employing the TaON as an effective oxygen evolution photocatalyst,SrTiO_(3):Rh as a hydrogen evolution photocatalyst,and reduced graphene oxide(rGO)as a solid-state electron mediator.This work presents a promising strategy for the synthesis of high-quality oxynitride materials in application to photocatalytic water splitting. 展开更多
关键词 TAON Oxynitride synthesis PHOTOCATALYST Water splitting Hydrogen Z-scheme
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Controlled fabrication of freestanding monolayer SiC by electron irradiation
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作者 笪蕴力 罗瑞春 +2 位作者 雷宝 季威 周武 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期31-37,共7页
The design and preparation of novel quantum materials with atomic precision are crucial for exploring new physics and for device applications.Electron irradiation has been demonstrated as an effective method for prepa... The design and preparation of novel quantum materials with atomic precision are crucial for exploring new physics and for device applications.Electron irradiation has been demonstrated as an effective method for preparing novel quantum materials and quantum structures that could be challenging to obtain otherwise.It features the advantages of precise control over the patterning of such new materials and their integration with other materials with different functionalities.Here,we present a new strategy for fabricating freestanding monolayer SiC within nanopores of a graphene membrane.By regulating the energy of the incident electron beam and the in-situ heating temperature in a scanning transmission electron microscope(STEM),we can effectively control the patterning of nanopores and subsequent growth of monolayer SiC within the graphene lattice.The resultant SiC monolayers seamlessly connect with the graphene lattice,forming a planar structure distinct by a wide direct bandgap.Our in-situ STEM observations further uncover that the growth of monolayer SiC within the graphene nanopore is driven by a combination of bond rotation and atom extrusion,providing new insights into the atom-by-atom self-assembly of freestanding two-dimensional(2D)monolayers. 展开更多
关键词 monolayer SiC 2D semiconductor in-situ growth in-situ STEM defect engineering graphene nanopores
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Atomically self-healing of structural defects in monolayer WSe_(2)
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作者 Kangshu Li Junxian Li +2 位作者 Xiaocang Han Wu Zhou Xiaoxu Zhao 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期49-55,共7页
Minimizing disorder and defects is crucial for realizing the full potential of two-dimensional transition metal dichalcogenides(TMDs) materials and improving device performance to desired properties. However, the meth... Minimizing disorder and defects is crucial for realizing the full potential of two-dimensional transition metal dichalcogenides(TMDs) materials and improving device performance to desired properties. However, the methods in defect controlcurrently face challenges with overly large operational areas and a lack of precision in targeting specific defects. Therefore,we propose a new method for the precise and universal defect healing of TMD materials, integrating real-time imaging withscanning transmission electron microscopy (STEM). This method employs electron beam irradiation to stimulate the diffusionmigration of surface-adsorbed adatoms on TMD materials grown by low-temperature molecular beam epitaxy (MBE),and heal defects within the diffusion range. This approach covers defect repairs ranging from zero-dimensional vacancydefects to two-dimensional grain orientation alignment, demonstrating its universality in terms of the types of samples anddefects. These findings offer insights into the use of atomic-level focused electron beams at appropriate voltages in STEMfor defect healing, providing valuable experience for achieving atomic-level precise fabrication of TMD materials. 展开更多
关键词 scanning transmission electron microscopy(STEM) atom manipulation nanoscale materials and structures:fabrication and characterization new materials:theory design FABRICATION
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First-principles study of electronic and magnetic properties of Fe atoms on Cu_(2)N/Cu(100)
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作者 陈佳乐 胡军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期498-503,共6页
First-principles calculations were conducted to investigate the structural,electronic,and magnetic properties of single Fe atoms and Fe dimers on Cu_(2)N/Cu(100).Upon adsorption of an Fe atom onto Cu_(2)N/Cu(100),robu... First-principles calculations were conducted to investigate the structural,electronic,and magnetic properties of single Fe atoms and Fe dimers on Cu_(2)N/Cu(100).Upon adsorption of an Fe atom onto Cu_(2)N/Cu(100),robust Fe-N bonds form,resulting in the incorporation of both single Fe atoms and Fe dimers within the surface Cu_(2)N layer.The partial occupancy of Fe-3d orbitals lead to large spin moments on the Fe atoms.Interestingly,both single Fe atoms and Fe dimers exhibit in-plane magnetic anisotropy,with the magnetic anisotropy energy(MAE)of an Fe dimer exceeding twice that of a single Fe atom.This magnetic anisotropy can be attributed to the predominant contribution of the component along the x direction of the spin-orbital coupling Hamiltonian.Additionally,the formation of Fe-Cu dimers may further boost the magnetic anisotropy,as the energy levels of the Fe-3d orbitals are remarkably influenced by the presence of Cu atoms.Our study manifests the significance of uncovering the origin of magnetic anisotropy in engineering the magnetic properties of magnetic nanostructures. 展开更多
关键词 magnetic nanostructures magnetic anisotropy spin–orbital coupling ultrathin substrate
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Design and prototyping of the readout electronics for the transition radiation detector in the high energy cosmic radiation detection facility
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作者 Jie-Yu Zhu Yang-Zhou Su +12 位作者 Hai-Bo Yang Fen-Hua Lu Yan Yang Xi-Wen Liu Ping Wei Shu-Cai Wan Hao-Qing Xie Xian-Qin Li Cong Dai Hui-Jun Hu Hong-Bang Liu Shu-Wen Tang Cheng-Xin Zhao 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期189-199,共11页
The high energy cosmic-radiation detection(HERD)facility is planned to launch in 2027 and scheduled to be installed on the China Space Station.It serves as a dark matter particle detector,a cosmic ray instrument,and a... The high energy cosmic-radiation detection(HERD)facility is planned to launch in 2027 and scheduled to be installed on the China Space Station.It serves as a dark matter particle detector,a cosmic ray instrument,and an observatory for high-energy gamma rays.A transition radiation detector placed on one of its lateral sides serves dual purpose,(ⅰ)calibrating HERD's electromagnetic calorimeter in the TeV energy range,and(ⅱ)serving as an independent detector for high-energy gamma rays.In this paper,the prototype readout electronics design of the transition radiation detector is demonstrated,which aims to accurately measure the charge of the anodes using the SAMPA application specific integrated circuit chip.The electronic performance of the prototype system is evaluated in terms of noise,linearity,and resolution.Through the presented design,each electronic channel can achieve a dynamic range of 0–100 fC,the RMS noise level not exceeding 0.15 fC,and the integral nonlinearity was<0.2%.To further verify the readout electronic performance,a joint test with the detector was carried out,and the results show that the prototype system can satisfy the requirements of the detector's scientific goals. 展开更多
关键词 HERD Dark matter particle detection TRD Readout electronics SAMPA Data acquisition Performance test
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Constraining the Earth-mass Primordial Black Hole Mergers Model of the Non-repeating FRBs Using the First CHIME/FRB Catalog
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作者 Min Meng Qiu-Ju Huang Can-Min Deng 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第9期76-82,共7页
In this paper,we upgrade the constraints for the Earth-mass primordial black hole mergers model based on the first Canadian Hydrogen Intensity Mapping Experiment(CHIME)/fast radio burst(FRB)catalog.Assuming the null h... In this paper,we upgrade the constraints for the Earth-mass primordial black hole mergers model based on the first Canadian Hydrogen Intensity Mapping Experiment(CHIME)/fast radio burst(FRB)catalog.Assuming the null hypothesis that the observed non-repeating FRBs originate from Earth-mass primordial black hole mergers,we find that how the charges were distributed in the primordial black hole population is well described by a double powerlaw function with typical charge value of law function with typical charge value of q_(c)/10^(-5)=1.60_(-0.28)^(+0.28),where the power-law index α_(1)=2.33_(-0.18)^(+0.15) for q<q_(c) and α_(2)=4.56_(-0.26)^(+0.30)for q≥q_(c).Here,q represents the charge of the black hole in units of√GM,where M is the mass of the black hole.Furthermore,we infer the local event rate of the bursts is 8.8_(-2.1)^(+5.7)×10^(4)Gpc^(-3) yr^(-1),which indicates that an abundance of the primordial black hole population f■10^(-4) is needed to account for the observed FRBs by CHIME.The results of this paper lay the basis for further research on the electromagnetic radiation background generated by the merger of primordial black hole mergers. 展开更多
关键词 black hole physics (stars:)gamma ray burst:general (cosmology:)dark matter
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The rise of supercapacitor diodes:Current progresses and future challenges
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作者 马鸿云 马凌霄 +1 位作者 毕华盛 兰伟 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期10-20,共11页
Supercapacitor has been widely known as a representative electrochemical energy storage device with high power density and long lifespan.Recently,with the deeper understanding of its charge storage mechanism,unidirect... Supercapacitor has been widely known as a representative electrochemical energy storage device with high power density and long lifespan.Recently,with the deeper understanding of its charge storage mechanism,unidirectional-charging supercapacitor,also called supercapacitor diode(CAPode),is successfully developed based on the ion-sieving effect of its working electrode towards electrolyte ions.Because CAPode integrates mobile ion and mobile electron in one hybrid circuit,it has a great potential in the emerging fields of ion/electron coupling logic operations,human–machine interface,neural network interaction,and in vivo diagnosis and treatment.Accordingly,we herein elucidate the working mechanism and design philosophy of CAPode,and summarize the electrode materials that are suitable for constructing CAPode.Meanwhile,some other supercapacitor-based devices beyond CAPode are also introduced,and their potential applications are instructively presented.Finally,we outline the challenges and chances of CAPode-related techniques. 展开更多
关键词 supercapacitor diode ion-sieving effect ion/electron coupling circuit logic operation
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Epitaxial growth of ultrathin gallium films on Cd(0001)
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作者 李佐 石明霞 +2 位作者 姚钢 陶敏龙 王俊忠 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期722-727,共6页
Growth and electronic properties of ultrathin Ga films on Cd(0001) are investigated by low-temperature scanning tunneling microscopy(STM) and density functional theory(DFT) calculations. It is found that Ga films exhi... Growth and electronic properties of ultrathin Ga films on Cd(0001) are investigated by low-temperature scanning tunneling microscopy(STM) and density functional theory(DFT) calculations. It is found that Ga films exhibit the epitaxial growth with the pseudomorphic 1×1 lattice. The Ga islands deposited at 100 K show a ramified shape due to the suppressed edge diffusion and corner crossing. Furthermore, the majority of Ga islands reveal flat tops and a preferred height of three atomic layers, indicating the electronic growth at low temperature. Annealing to room temperature leads to not only the growth mode transition from electronic growth to conventional Stranski–Krastanov growth, but also the shape transition from ramified islands to smooth compact islands. Scanning tunneling spectroscopy(STS) measurements reveal that the Ga monolayer exhibits metallic behavior. DFT calculations indicate that all the interfacial Ga atoms occupy the energetically favorable hcp-hollow sites of the substrate. The charge density difference analysis demonstrates that the charge transfer from the Cd substrate to the Ga atoms is negligible, and there is weak interaction between Ga atoms and the Cd substrate. These results shall shed important light on fabrication of ultrathin Ga films on metal substrates with novel physical properties. 展开更多
关键词 gallium films electronic growth STM/STS density functional theory
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Development of 400-μW cryogen-free dilution refrigerators for quantum experiments
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作者 关翔 樊洁 +2 位作者 边勇波 程智刚 姬忠庆 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期28-35,共8页
We have successfully developed cryogen-free dilution refrigerators with medium cooling power that can be applied to quantum experiments. Breakthroughs have been made in some key technologies and components of heat swi... We have successfully developed cryogen-free dilution refrigerators with medium cooling power that can be applied to quantum experiments. Breakthroughs have been made in some key technologies and components of heat switches and dilution units. Our prototype has been running continuously and stably for more than 100 hours below 10 m K, with a minimum temperature of 7.6 m K and a cooling power of 450 μW at 100 m K. At the same time, we have also made progress in the application of dilution refrigerators, such as quantum computing, low-temperature detector, and magnet integration. These indicators and test results indicate good prospects for application in physics, astronomy, and quantum information. 展开更多
关键词 cryogen-free dilution refrigerator quantum computing low-temperature detector superconducting magnet
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Image segmentation of exfoliated two-dimensional materials by generative adversarial network-based data augmentation
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作者 程晓昱 解晨雪 +6 位作者 刘宇伦 白瑞雪 肖南海 任琰博 张喜林 马惠 蒋崇云 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期112-117,共6页
Mechanically cleaved two-dimensional materials are random in size and thickness.Recognizing atomically thin flakes by human experts is inefficient and unsuitable for scalable production.Deep learning algorithms have b... Mechanically cleaved two-dimensional materials are random in size and thickness.Recognizing atomically thin flakes by human experts is inefficient and unsuitable for scalable production.Deep learning algorithms have been adopted as an alternative,nevertheless a major challenge is a lack of sufficient actual training images.Here we report the generation of synthetic two-dimensional materials images using StyleGAN3 to complement the dataset.DeepLabv3Plus network is trained with the synthetic images which reduces overfitting and improves recognition accuracy to over 90%.A semi-supervisory technique for labeling images is introduced to reduce manual efforts.The sharper edges recognized by this method facilitate material stacking with precise edge alignment,which benefits exploring novel properties of layered-material devices that crucially depend on the interlayer twist-angle.This feasible and efficient method allows for the rapid and high-quality manufacturing of atomically thin materials and devices. 展开更多
关键词 two-dimensional materials deep learning data augmentation generating adversarial networks
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