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C^MC^N D-computable state

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Science china({1.,Mechanics & Astronomy) 2008年第9期51卷 1300-1307页

作者： LIU DongDong1.2 & DI YaoMin1.1.school of {1. & electronic engineering,Xuzhou normal university,Xuzhou 221.1.,china 2 school of Mathematics & {1. Science,Xuzhou Institute of Technology,Xuzhou 221.08,china school of {1. & electronic engineering Xuzhou Normal University Xuzhou China school of Mathematics & {1. Science Xuzhou Institute of Technology Xuzhou China

The notions of D-computable state and D-concurrence are generalized to the CMCN system. A class of D-computable state on CMCN is given and the calculating method of the lower bound of D-concurrence is provided. Th... 详细信息

关键词： quantum entanglement entanglement of formation concurrence D-computable state

Quality evaluation for air plasma spray thermal barrier coatings with pulsed thermography

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Progress in Natural Science:Materials International 2011年第4期21卷 301-306页

作者： Shi-bin ZHAO~1.Cun-lin ZHANG~2,Nai-ming WU~3,Hua-ming {1.~1.1.school of Materials Science and engineering,Beihang university,Beijing 1.01.1.china 2.Department of physics,Capital normal university,Beijing 1.0048,china 3.school of Jet Propulsion,Beihang university,Beijing 1.01.1.china school of Materials Science and {1. Beihang University Beijing 100191 China Department of physics Capital Normal University Beijing 100048 China school of Jet Propulsion Beihang University Beijing 100191 China

Pulsed thermography(PT) as a non-contact non-destructive evaluation(NDE) technique was employed to examine as-sprayed air plasma spray(APS) thermal barrier coatings(TBCs) for quality *** and micro-structural characteristics play a vital role in determining the *** this paper,PT logarithmic peak second-derivative method was adopted to measure the thickness of top *** dependent thermal images were used to characterize the microstructure which was confirmed by scanning electron microscope(SEM).The results showed that there was relationship between the temperature distribution of the surface and microstructure change in *** distribution in thermal images and measurement results of thickness were in fairly good agreement with the microstructure *** can be concluded that it was possible to employ these NDE methods as quality evaluation for as-sprayed TBCs.

关键词： thermal barrier coatings(TBCs) non-destructive evaluation(NDE) pulsed thermography microstructure thickness measurement

A photometric study of the K-type contact binary EI CVn

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Research in Astronomy and Astrophysics 2011年第2期11卷 181-190页

作者： Yuan-Gui Yang school of {1. and electronic Information,Huaibei normal university,Huaibei 235000,china school of {1. and electronic Information Huaibei Normal University Huaibei 235000 China

We present charge-coupled device （CCD） photometry for the short-period K-type binary EI CVn,observed on 2009 February 28 at the Xinglong Station of National Astronomical Observatories,Chinese Academy of *** using the Wilson-Devinney program,the photometric solution was first deduced from our V R *** results show that EI CVn is a W-type weak-contact binary with a mass ratio of qph=0.2834（±0.001.） and an overcontact degree of f=20.0%（±0.7%）.The distorted light curves were modeled by a dark spot on the cool primary component,whose area was up to 1.9% of the area of the *** on the period analysis,it is found that there exists a weak secular decrease at a rate of dP/dt= 3.1.（±0.03） × 1.-7 d yr-1.which may be attributed to mass transfer from the primary to the *** mass transfer occurring,the separation between both components will shrink,which may cause the degree of overcontact to ***,the weak-contact binary EI CVn may evolve into a deep-contact configuration.

关键词： stars: binaries: close -- stars: binaries: eclipsing -- stars: individual: EICVn

Tunneling conductance in graphene ferromagnet/p wave superconductor junctions

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Science china({1.,Mechanics & Astronomy) 2012年第4期Mechanics & Astronomy) .卷 649-653页

作者： LI XiaoWei 1.2*,CHEN HuaBao 1.& LIU ShuJing 1.1.school of {1. and electronic Electrical engineering,Huaiyin normal university,Huaian 223300,china 2 State Key Laboratory of Functional Materials for Informatics,Shanghai Institute of Microsystem and Information Technology,Chinese Academy of Sciences,Shanghai 200050,china school of {1. and electronic Electrical engineering Huaiyin Normal University Huaian China State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai China

Using the extended Blonder-Tinkham-Klapwijk formalism,we investigate the conductance spectra of graphene ferromagnet/p wave superconductor *** is found that the conductance spectra are affected by the p wave pairing *** ferromagnetic exchange energy in the ferromagnet can suppress Andreev retroreflection but enhance the specular Andreev reflection in graphene ferromagnet/p wave superconductor *** conductance decreases with increasing exchange energy Eh for EhEF.

关键词： graphene ferromagnet p wave superconductor tunneling conductance

A computational investigation of boron-doped chromium and chromium clusters by density functional theory

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Science china({1.,Mechanics & Astronomy) 2010年第5期53卷 812-817页

作者： GE GuiXian1,JING Qun1 & LUO YouHua2,3 1 Key Laboratory of Ecophysics and Department of physics,normal College,Shihezi university,Xinjiang 832003,china 2 school of Science,East china university of Science and Technology,Shanghai 200237,china 3 Institute of Theoretical physics,school of physics and Information Optoelectronics,Henan university,Kaifeng 475004,china Key Laboratory of Ecophysics and Department of physics Normal College Shihezi University Xinjiang China school of Science East China University of Science and Technology Shanghai China Institute of Theoretical physics School of Physics and Information Optoelectronics Henan University Kaifeng China

The geometries,stabilities and electronic properties of Crn and CrnB(n=2-9) clusters have been systematically investigated by density functional *** results suggest that the lowest energy structures for CrnB clusters can be obtained by substituting one Cr atom in Crn+1.clusters with B *** geometries of CrnB clusters are similar to that of Crn+1.clusters except for local structural *** second-order difference and fragmentation energy show Cr4,Cr6,Cr8,Cr3B,Cr5B and Cr8B cluster are the most stable among these studied *** impurity B increases the stabilities of chromium *** B is doped on the Crn clusters,cluster geometry does dominate positive role in enhancing their *** doped B atom does not change the coup{1.g way of the Cr site in Crn clusters,but breaks the symmetry and the Cr atoms are no longer *** doped B atom increases the total magnetic moments of Crn in most cases.

关键词： Crn and CrnB clusters geometries electronic properties

3D interlocked all-textile structured triboelectric pressure sensor for accurately measuring epidermal pulse waves in amphibious environments

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Nano Research 2024年第3期17卷 1923-1932页

作者： Shaobo Si Chenchen Sun Yufen Wu Jingjing Li Han wang Yinggang {1. Jin Yang Zhong {1. wang Department of Optoelectronic {1. Key Laboratory of Optoelectronic Technology and Systems Ministry of EducationChongqing UniversityChongqing 400044China College of physics and {1. engineering Chongqing Normal UniversityChongqing 401331China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 100083China school of Materials Science and {1. Georgia Institute of TechnologyAtlantaGA 30332USA

The performance degradation and even damage of the e-textiles caused by sweat,water,or submersion during all-weather health monitoring are the main reasons that e-textiles have not been commercialized and routinized so ***,we developed an amphibious,high-performance,air-permeable,and comfortable all-textile triboelectric sensor for continuous and precise measurement of epidermal pulse waves during full-day *** on the principle of preparing gas by acid-base neutralization reaction,a one-piece preparation process of amphibious conductive yarn(ACY)with densely porous structures is *** innovative three-dimensional(3D)interlocking fabric knitted from ACYs(0.6 mm in diameter)and polytetrafluoroethylene yarns exhibit high sensitivity(0.433 V·kPa^(-1.),wide bandwidth(up to 1. Hz),and stability(>30,000 cycles).With these benefits,98.8%agreement was achieved between wrist pulse waves acquired by the sensor and a high-precision laser ***,the polytetrafluoroethylene yarn with good compression resilience provides sufficient mechanical support for the contact separation of the ***,the unique skeletonized design of the 3D interlocking structure can effectively relieve the water pressure on the sensor surface to obtain stable and accurate pulse waves(underwater depth of 5 cm).This achievement represents an important step in improving the practicality of e-textiles and early diagnosis of cardiovascular diseases.

关键词： triboelectric pressure sensor amphibious fabric interlocking fabric pulse wave measurement one-piece preparation method

Density functional theory study on the structural and electronic properties of Ag-adsorbed (MgO)_n clusters

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Science china({1.,Mechanics & Astronomy) 2009年第5期52卷 734-741页

作者： GE GuiXian1. JING Qun1.& LUO YouHua2,3 1.Key Laboratory of Ecophysics and Department of physics, normal College, Shihezi university, Shihezi 832003, china 2 school of Science, East china university of Science and Technology, Shanghai 200237, china 3 Institute for Theoretical physics, Henan university, Kaifeng 475004, china Key Laboratory of Ecophysics and Department of physics Normal College Shihezi University Shihezi China school of Science East China University of Science and Technology Shanghai China Institute for Theoretical physics Henan University Kaifeng China

Equilibrium geometries, charge distributions, stabilities and electronic properties of the Ag-adsorbed (MgO)n (n = 1.8) clusters have been investigated by density functional theory (DFT) with generalized gradient approximation (GGA) for exchange-correlation functional. The results show that hollow site is energetically preferred for n≥4, and the incoming Ag atoms tend to cluster on the existing Ag cluster. The Mulliken populations indicate that the interaction between the Ag atom and Magnesia clusters is mainly induced by a weak atomic polarization. The adsorbed Ag atom only causes charge redistributions of the atoms near itself. The effect of the adsorbed Ag atom on the bonding natures and structural features of Magnesia clusters is minor. Furthermore, the investigations on the first energy difference, fragmentation energies and electron affinities show that the Ag(MgO)4 and Ag(MgO)6 are the most stable among studied clusters.

关键词： Ag (MgO)_n clusters geometries electronic properties

Up-conversion emissions of Er^(3+)-Yb^(3+) codoped Al_2O_3 nanoparticles by the arc discharge synthesis method

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Science china({1.,Mechanics & Astronomy) 2009年第7期52卷 1043-1046页

作者： DONG Bin1, CAO BaoSheng1, FENG ZhiQing1, wang XingJun2, LI ChengRen3 & HUA RuiNian4 1 school of Science, Dalian Nationalities university, Dalian 116600, china 2 school of electronics engineering and Computer Science, Peking university, Beijing 100871, china 3 College of physics and electronic Technology, Liaoning normal university, Dalian 116029, china 4 College of Life Science, Dalian Nationalities university, Dalian 116600, china school of Science Dalian Nationalities University Dalian China school of {1.s engineering and Computer Science Peking University Beijing China College of physics and {1. Technology Liaoning Normal University Dalian China College of Life Science Dalian Nationalities University Dalian China

The Er3+-Yb3+ codoped Al2O3 nanoparticles with an average particle size of about 50 nm have been synthesized by an arc discharge synthesis method. The green and red up-conversion emissions centered at about 526, 547 and 677 nm, corresponding respectively to the 2H1./2→4I1./2, 4S3/2→4I1./2 and 4 F9/2→4I1./2 transitions of Er3+, were detected by a 978-nm semiconductor laser diode excitation. The Annealing has evident effect on the up-conversion emissions of the samples: The red up-conversion emission is noticeable before annealing; however, the green up-conversion emission becomes predominant after annealing. The mixture of (Er,Yb)3Al5O1. and α-(Al,Er,Yb)2O3 phases is more favorable for green up-conversion emissions due to an enhancement of the ESA (I) of 4I1./2+a photon→4F7/2 and ET (III) of 2F5/2(Yb3+)+4I1./2(Er3+)→2F7/2(Yb3+)+4F7/2(Er3+) processes. The two-photon absorption up-conversion process is involved in the green and red up-conversion emissions. The results have proved that arc discharge synthesis is a new promising preparation technology for optical materials.

关键词： up-conversion Er3+-Yb3+ codoped Al2O3 arc discharge synthesis

Research on intelligent search-and-secure technology in accelerator hazardous areas based on machine vision

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Nuclear Science and Techniques 2024年第4期35卷 96-107页

作者： Ying-lin Ma Yao {1. Hong-Mei Shi Hui-Jie Zhang school of Traffic and Transportation Beijing Jiaotong UniversityBeijing 100044China school of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Institute of High Energy physics Chinese Academy of SciencesBeijing 100049China

Prompt radiation emitted during accelerator operation poses a significant health risk,necessitating a thorough search and securing of hazardous areas prior to ***,manual sweep methods are ***,the limitations of manual sweeps have become increasingly evident with the implementation of large-scale *** leveraging advancements in machine vision technology,the automatic identification of stranded personnel in controlled areas through camera imagery presents a viable solution for efficient search and *** the criticality of personal safety for stranded individuals,search and security processes must be sufficiently *** ensure comprehensive coverage,1.0°camera groups were strategically positioned on both sides of the accelerator tunnel to eliminate blind spots within the monitoring *** YOLOV8 network model was modified to enable the detection of small targets,such as hands and feet,as well as larger targets formed by individuals near the ***,the system incorporates a pedestrian recognition model that detects human body parts,and an information fusion strategy is used to integrate the detected head,hands,and feet with the identified pedestrians as a cohesive *** strategy enhanced the capability of the model to identify pedestrians obstructed by equipment,resulting in a notable improvement in the recall ***,recall rates of 0.91. and 0.82were obtained for Datasets 1.and 2,*** there was a slight decrease in accuracy,it aligned with the intended purpose of the search-and-secure software *** tests conducted within an accelerator tunnel demonstrated the effectiveness of this approach in achieving reliable recognition outcomes.

关键词： Search and secure Machine vision Camera Human body parts recognition Particle accelerator Hazardous area