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A distributed control system for picosecond accelerator at SINAP

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Nuclear Science and Techniques 2005年第4期16卷 201-203页

作者： CAO Hong-Ping CHEN Huan-Guang li de-ming Shanghai Institute of Applied Physics the Chinese Academy of Sciences Shanghai 201800 Graduate School of the Chinese Academy of Sciences Beijing 100049

The picosecond accelerator (PA) is a low energy electron linear accelerator facility under commissioning, which is built for the experiment of ps level pulse radiolysis in Shanghai Institute of Applied Physics (SINAP). A practical distributed DA&C system for this facility has been developed. In view of the upgrading-ability and main-tainability of the control system and controlled devices, Advantech? distributed intelligent DA&C products are adopted into the control system. ADAM 5000/TCPs with the protocol of Modbus/TCP are employed to accomplish data acquisition and device control. The PC-compatible programmable logic controller, ADAM-5511, is also adopted to handle the interlocks and the emergency events. On the software side, the integrated software package King-view?V6.5, which friendly supports all Advantech products, has been used to develop the upper layer control logic and process the data. This paper describes the control system design and system architecture. The intelligent ADAM controllers and the software platform are also discussed in detail.

关键词： SINAP 加速器控制系统电子束 ADAM

Magnet lattice design of the SSRF electron-beam transfer lines

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Nuclear Science and Techniques 2006年第4期17卷 193-197页

作者： HAN Yi-Ang liU Gui-Min li de-ming Shanghai Institute of Applied Physics The Chinese Academy of Sciences Shanghai 201800 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

Under three-dimensional plane geometrical constraints ( X,Y,θ ), with two asymmetric achromatic sections, the combined three-section structural FODO-like magnet lattice design is adopted and finely optimized in the SSRF electron-beam transfer lines. The magnet lattice has high flexibility and robustness, and the Courant–Snyder parameters can be easily adjusted within a wide range to meet the requirements of transmission and injection for different operation modes of the linear accelerator, booster synchrotron, and storage ring. In this article, the main parameters of the linear optics design of the SSRF electron-beam transfer lines are described, involving the physical design criteria, the total geometrical layout, the magnet lattice, and the beam Courant–Snyder parameters matching. The studies of the variant beam dynamic simulation program calculations show that the design purpose of the efficient beam transmission and injection will be basically achieved.

关键词：上海同步加速器辐射设备电子束传送线几何规划电子束匹配

Analysis of transmission efficiency of SSRF electron beam transfer lines

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Nuclear Science and Techniques 2006年第2期17卷 65-70页

作者： HAN Yi-Ang HOU Jie liU Gui-Min li de-ming Shanghai Institute of Applied Physics the Chinese Academy of Sciences Shanghai 201800 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

In this article, the main factors which influence transmission efficiency of the SSRF electron beam trans- fer lines are described, including physical requirements for magnet system, vacuum system, beam diagnostic system, trajectory correction system, etc. The dynamic simulation calculation and transmission efficiency analysis of the SSRF electron beam transfer lines are presented, and the studies show that the design purpose of efficient beam transmission and injection will be achieved.

关键词： SSRF 迁移线动态模拟传输效率

Virtual instrument for controlling and monitoring digitalized power supply in SSRF

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Nuclear Science and Techniques 2006年第3期17卷 129-134页

作者： TANG Jun-Long XU Rui-Nian CHEN Huan-Guang SHEN Tian-Jian li de-ming Shanghai Institute of Applied Physics the Chinese Academy of Sciences Shanghai 201800 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

The Shanghai Synchrotron Radiation Facility (SSRF) needs extremely precise power supplies for their various magnets. A digital controller is being developed for the power converters of the SSRF power supply (PS). In the digital controller, a fully digital pulse-width modulator (PWM) directly controls the power unit insulated gate bipolar transistor (IGBT) of the PS. A program in LabVIEW language has been developed to control and monitor the digital PS via serial communication (RS232) from a PC and to modify its parameters as well. In this article, the software design of the virtual instrument for controlling and monitoring digitalized PS and its associated functions are described, and the essential elements of the program graphical main-VI and sub-VI source code are presented and explained. The com- munication protocol and the structure of the developed system are also included in this article.

关键词：数字功率供给虚拟工具 SSRF PWM

Passive mode locked diode-pumped Nd:GdYVO_4 laser with a GaAs absorber

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Optoelectronics Letters 2008年第6期4卷 422-424页

作者： DAI Wei li de-chuan WANG ming-jian ZHANG Shuai-yi YU Guo-lei li Jian College of Physics and Electronics Shandong Normal University Jinan 250014 China

A passively Q-switched mode-locked Nd:GdYVO4 laser is successfully demonstrated by using a piece of GaAs crystal grown at low temperature as the passively saturated absorber and the output coupler. Fundamental properties of the Nd: GdYVO4 laser are investigated. The maximum average output power of 3.5 W is obtained by using plainsphere when the incident pumping power is 10 W,which corresponds to an optical-optical coversion efficiency of 35%. The threshold power for the Q-switching mode-locked is 1.2 W. The maximum average output power of 1.72 W is obtained by using GaAs when the incident pumping power is 10 W,mode-locked pulse train with a repetition rate of ～113 MHz is achieved. At the incident laser pumping power of 7 W,the modulation depth is 100%.

关键词：滤波器 GaAs Nd:GdYVO4 激光器

The Star Chromatic Numbers of Some Planar Graphs derived from Wheels

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Acta Mathematica Sinica,English Series 2002年第1期18卷 173-180页

作者： li de ming department of Mathematics. Capital Normal University. Beijing 100037. P. R. China department of Mathematics Capital Normal University Beijing P. R. China

The notion of the star chromatic number of a graph is a generalization of the chromatic number. In this paper. we calculate the star chromatic numbers of three infinite families of planar graphs. The first two families are derived from a 3-or 5-wheel by subdivisions. their star chromatic numbers being 2+2/(2n + 1). 2+3/(3n + 1)and 2+3/ (3n - 1), respectively. The third family of planar graphs are derived from n odd wheels by Hajos construction with star chromatic numbers 3 + 1/n. which is a generalization of one resnlt of Gao et al.

关键词： (k,d)-coloring Star chromatic number Planar graph

Endoscopic diagnosis and treatment of biliary leak in patients following liver transplantation:a prospective clinical study

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Hepatobiliary & Pancreatic Diseases International 2007年第1期6卷 29-33页

作者： liao, Jia-Zhi Zhao, Qiu Qin, Hua li, Rong-Xiang Hou, Wei li, Pei-Yuan liu, Nan-Zhi li, de-ming Huazhong Univ Sci & Technol Tongji Hosp Tonji Med Coll Dept Gastroenterol Wuhan 430030 Peoples R China

BACKGROUND: Orthotopic liver transplantation has been widely used in patients with end-stage liver disease within the last two decades. However, the prevalence of biliary complications after liver transplantation remains high. The most common short-term biliary complication may be biliary leak. So, we examined 13 patients with biliary leak after liver transplantation, attempting to evaluate the role of endoscopic diagnosis and treatment of biliary leak and the incidence of bile duct stricture after healing of the leak. METHODS: Six cases of T-tube leak and seven cases of anastomosis leak complicating liver transplantation were enrolled in this prospective study. Six patients were treated by endoscopic plastic stent placement, two by nasobiliary catheter drainage, two by papillosphincterotomy, and three by nasobiliary catheter drainage combined with plastic stent placement. Some patients received growth hormone treatment. RESULTS: The bile leak resolution time was 10-35 days in 10 patients with complete documentation. The median time of leak resolution was 15.3 days. Four cases of anastomosis stricture, three cases of common hepatic duct and one case of multiple bile duct stenosis were detected by follow-up nasobiliary catheter cholangiography or endoscopic retrograde cholangiopancreatography. CONCLUSIONS: Endoscopic nasobiliary catheter or plastic stent placement is a safe and effective treatment for bile duct stricture occurring after bile leak resolution in most liver transplantation patients. Nasobiliary catheter combined with plastic stent placement may be the best choice for treating bile leak, because, theoretically, it may prevent the serious condition resulting from accidental nasobiliary catheter dislocation, and it may have prophylactic effects on upcoming bile duct stricture, although this should be further confirmed.

关键词： liver transplantation biliary leak bile duct stricture endoscopic therapy endoscopic retrograde cholangiopancreatography nasobiliary tube stent

Phosphorus Status and Risk of Phosphate Leaching Loss From Vegetable Soils of Different Planting Years in Suburbs of Changsha, China

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Agricultural Sciences in China 2010年第11期9卷 1641-1649页

作者： QIN Hong-ling QUAN Zhi liU Xin-liang li ming-de ZONG Yong WU Jin-shui WEI Wen-xue Key Laboratory of Agro-Ecological Processes in Subtropical Region Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 P.R China Institute of Soil and Fertilizer Hunan Academy of Agricultural Sciences Changsha 410125 P.R.China

The aim of the study was to develop an index to assess the environmental risk of P loss potential in vegetable soils with chronic difference of plantation in the suburbs of Changsha, Hunan Province, China. Chemical methodology was used to study soil phosphorus status and the relationships between available P in soil and potential soil leaching P. The results showed that there was a significant linear relationship between Olsen P and CaC12-P or P concentration in soil solution. Olsen P increased sharply when either CaCI2-P or P concentration in soil solution reached a certain level. It was confirmed that 80 mg kg-t of Olsen P was the critical value of soil P leaching in the vegetable soils. P leaching probability over the critical was assessed by GIS and indicator Kriging and four secondary risks of phosphorus leaching loss were defined. In the area with vegetable cropping for over 30 yr （Chenjiadu） and 10-15 planting years （Huangxingzhen）, the indices of phosphorus leaching loss risk were 3 and 2.93, respectively. These two areas belonged to strong secondary of risk of phosphate leaching loss. In the new vegetable planting field less than 2 yr （Ningxiang）, the index was 0.06, which had almost no risk of phosphorus leaching. In vegetable soils in the suburban region of Changsha, the phosphorus leaching peotential is high and the phosphorus leaching loss is related to chronic length of vegetable cropping.

关键词： vegetable soils critical value P leaching probability risk assessment

On the decay Number of a Graph

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Chinese Quarterly Journal of Mathematics 2005年第2期20卷 121-127页

作者： lide-ming departmentofMathematics CapitalNormalUniversityBeijing100037China

The decay number of a connected graph is defined to be the minimum number of the components of the cotree of the graph. Upper bounds of the decay numbers of graphs are obtained according to their edge connectivities. All the bounds in this paper are ***, for each integer k between one and the upper bound, there are infinitely many graphs with the decay number k.

关键词： decay number edge connectivity bound