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Development of scanning transmission ion microscopy computed tomography at Fudan microbeam line
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作者 LI Yongqiang HABCHI Claire +2 位作者 LIU Xue LIU Yiyang SHEN Hao 《Nuclear Science and Techniques》 SCIE CAS CSCD 2013年第4期5-8,共4页
The computed tomography was applied to setting STIM(Scanning Transmission Ion Microscopy) projections recorded at the Fudan Ion Beam Laboratory.In this work,in order to visualize the three-dimensional mass density dis... The computed tomography was applied to setting STIM(Scanning Transmission Ion Microscopy) projections recorded at the Fudan Ion Beam Laboratory.In this work,in order to visualize the three-dimensional mass density distribution in several specimens,example for a test structure of hollow gold cyliner was presented together with a detailed description of the developed system,including data reconstruction code(Tomorebuild 2) and image display software(AMIRA).Future development will allow the particle induced X-ray emission tomography for elemental analysis of micrometer-sized samples. 展开更多
关键词 计算机断层扫描 离子束 透射 线扫描 开发 微束 X射线发射 STIM
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Edge detection and mathematic fitting for corneal surface with Matlab software 被引量:9
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作者 Yue Di Mei-Yan Li +1 位作者 Tong Qiao Na Lu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第3期336-342,共7页
AIM:To select the optimal edge detection methods to identify the corneal surface,and compare three fitting curve equations with Matlab software. METHODS:Fifteen subjects were recruited. The corneal images from optic... AIM:To select the optimal edge detection methods to identify the corneal surface,and compare three fitting curve equations with Matlab software. METHODS:Fifteen subjects were recruited. The corneal images from optical coherence tomography(OCT)were imported into Matlab software. Five edge detection methods(Canny,Log,Prewitt,Roberts,Sobel)were used to identify the corneal surface. Then two manual identifying methods(ginput and getpts)were applied to identify the edge coordinates respectively. The differences among these methods were compared. Binomial curve(y=Ax2+Bx+C),Polynomial curve [p(x)=p1xn+p2x(n-1)+....+pnx+pn+1] and Conic section(Ax2+Bxy+Cy2+Dx+Ey+F=0)were used for curve fitting the corneal surface respectively. The relative merits among three fitting curves were analyzed. Finally,the eccentricity(e)obtained by corneal topography and conic section were compared with paired t-test. RESULTS:Five edge detection algorithms all had continuous coordinates which indicated the edge of the corneal surface. The ordinates of manual identifying were close to the inside of the actual edges. Binomial curve was greatly affected by tilt angle. Polynomial curve was lack of geometrical properties and unstable. Conic section could calculate the tilted symmetry axis,eccentricity,circle center,etc. There were no significant differences between 'e' values by corneal topography and conic section(t=0.9143,P=0.3760 〉0.05).CONCLUSION:It is feasible to simulate the corneal surface with mathematical curve with Matlab software. Edge detection has better repeatability and higher efficiency. The manual identifying approach is an indispensable complement for detection. Polynomial and conic section are both the alternative methods for corneal curve fitting. Conic curve was the optimal choice based on the specific geometrical properties. 展开更多
关键词 Matlab software edge detection curve fitting mathematic simulation optical coherence tomography corneal topography
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CHARGE-TRANSFER AND ENERGY-TRANSFER IN THE PHOTO-INDUCED COPOLYMERIZATION OF 2-VINYLNAPHTHALENE WITH MALEIC ANHYDRIDE
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作者 李橦 罗彬 +1 位作者 李善君 储国蓓 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1990年第2期170-176,共7页
The initiation mechanism of the copolymerization of 2-vinylnaphthalene with maleic anhydride was studied under irradiation of 365 nm. The excited complex was formed from (1) the local excitation of 2-vinylnaphthalene ... The initiation mechanism of the copolymerization of 2-vinylnaphthalene with maleic anhydride was studied under irradiation of 365 nm. The excited complex was formed from (1) the local excitation of 2-vinylnaphthalene followed by the charge-transfer interaction with maleic anhydride and (2) the excitation of the ground state charge-transfer complex, and then it collapsed to 1,4-tetramethylene biradical for initiation. A1: 1 alternating copolymer was formed in different monomer feeds. Addition of benzophenone could greatly enhance the rate of copolymerization through energy-transfer mechanism. 展开更多
关键词 THAN CHARGE-TRANSFER AND ENERGY-TRANSFER IN THE PHOTO-INDUCED COPOLYMERIZATION OF 2-VINYLNAPHTHALENE WITH MALEIC ANHYDRIDE DEF
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Standards for Tunnel and Road LED Lighting Application Technologies
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作者 杨方勤 《China Standardization》 2014年第5期62-67,共6页
The paper summarizes the research on the development of standards for tunnels and roads LED lighiing application in Shanghai. analyzes the existing problems on LED road lamps and lighting design, introduces the experi... The paper summarizes the research on the development of standards for tunnels and roads LED lighiing application in Shanghai. analyzes the existing problems on LED road lamps and lighting design, introduces the experiments and testing results, and summarizes current problems of LED street lighting, proposing that LED lighting energy conservation should he "systematic energy saving" throughout the full life cycle based on the integration of products and applications. 展开更多
关键词 standards for LED tunnel and street light hill life-cycle energy conservation combination of product and application
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THE SPECTRUM OF CONTRACTIVE OPERATORS ON π_k
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作者 陈晓漫 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1989年第4期480-485,共6页
In this paper, it is shown that, for a contraction on π_k, the intersection of its spectrum with the exterior of the unit disk is a finite set of isolated eigenvalues, each of which has finite multplicity. Futhermore... In this paper, it is shown that, for a contraction on π_k, the intersection of its spectrum with the exterior of the unit disk is a finite set of isolated eigenvalues, each of which has finite multplicity. Futhermore some relations between its spectrum and the spectrum of its minimal unitary dilation are established. 展开更多
关键词 INTERSECTION DILATION EXTERIOR UNITARY CONTRACTION assume 下军 CONVENIENCE decomp 息土
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