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Clock distribution and local oscillator of a digital low-level radio-frequency board for SSRF

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Nuclear Science and Techniques 2010年第1期21卷 7-10页

作者： FU Zechuan ZHAO Yubin liu Jianfei ZHAO zhentang Shanghai Institute of AppliedPhysics Chinese Academy of Sciences Shanghai 201800 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Shanghai Key Laboratory of Cryogenics ＆Superconducting FR Technology Shanghai 201800 China

In the storage ring RF system of Shanghai Synchrotron Radiation Facility,the clock distribution and the local oscillator are two parts of the digital low level radio frequency hardware *** this paper,we designed and produced the clock distribution and the local oscillator board using the AD9858 and AD9510 *** results show that the phase noise of the local oscillator signal is lower than 100dBc/Hz with 50 kHz offset.

关键词：上海同步辐射装置时钟分配本振信号电路板射频本地振荡器光源和数

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数控转塔冲床的新型机械主传动系统

机械工人（热加工） 2007年第4期31卷 32-32页

作者：刘振堂济南铸锻所捷迈机械有限公司山东250022

1．概述数控转塔冲床是一种柔性的薄板冲孔加工设备。机床根据加工程序，在控制系统的协调控制下工作；板料由夹钳夹持，经伺服电动机驱动，滚珠丝杠的传动使板料在工作台的X、Y向定位，模具轴选择模具并定位，打击滑块冲击模具冲压板... 详细信息

1．概述数控转塔冲床是一种柔性的薄板冲孔加工设备。机床根据加工程序，在控制系统的协调控制下工作；板料由夹钳夹持，经伺服电动机驱动，滚珠丝杠的传动使板料在工作台的X、Y向定位，模具轴选择模具并定位，打击滑块冲击模具冲压板料。主传动系统负责模具的冲压控制和动力提供。

关键词：数控转塔冲床主传动系统机械协调控制电动机驱动加工设备加工程序控制系统

A single stage EEHG at SXFEL for narrow-bandwidth soft X-ray generation

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Science Bulletin 2016年第15期61卷 1202-1212页

作者： Chao Feng Dazhang Huang Haixiao Deng Jianhui Chen Dao Xiang Bo liu DongWang zhentang Zhao Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China Department of Physics and Astronomy Key Laboratory for Laser Plasma Shanghai Jiao Tong University Shanghai 200240China

The echo-enabled harmonic generation （EEHG） scheme holds promising prospects for efficiently generat- ing intense coherent radiation at very high harmonics of the initial seed laser. In this paper, we study the feasibility of operating the Shanghai X-ray free-electron laser test facility with a single stage EEHG setup. With a combina- tion of existing numerical codes, start-to-end simulations considering various three-dimensional effects have been carried out to show the possible performance of the EEHG FEL. Simulation results demonstrate that a single stage EEHG can generate high power soft X-ray radiation pulses with narrow bandwidth directly from UV seed lasers. With the help of the harmonic lasing technique or upgraded linac, we also show the possibility of generating coherent soft X-ray radiation in the ＂water window＂ with a single stage EEHG.

关键词： X-ray free-electron lasers EEHG Coherent soft X-ray Harmonic lasing Waterwindow

Features and futures of X-ray free-electron lasers

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The Innovation 2021年第2期2卷 54-72页

作者： Nanshun Huang Haixiao Deng Bo liu Dong Wang zhentang Zhao Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

Linear accelerator-based free-electron lasers(FELs)are the leading source of fully coherent X-rays with ultra-high peak powers and ultrashort pulse *** X-ray FEL facilities have proved their worth as useful tools for diverse scientific *** this paper,we present an overview of the features and future prospects of X-ray FELs,including the working principles and properties of X-ray FELs,the operational status of different FEL facilities worldwide,the applications supported by such facilities,and the current developments and outlook for X-ray FEL-based research.

关键词： lasers ultrashort free

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安全工程专业本科实习教学模式探索

实验科学与技术 2017年第3期15卷 83-87页

作者：杨永良李增华侯世松刘贞堂仲晓星中国矿业大学安全工程学院江苏徐州221116 中国矿业大学煤矿瓦斯与火灾防治教育部重点实验室江苏徐州221116 中国矿业大学煤炭资源与安全开采国家重点实验室江苏徐州221116

高校本科实习是专业教学计划的重要组成部分,而实习模式是实习效果好坏的关键因素。该文在分析现有实习模式存在问题的基础上,结合专业的办学定位和专业特色,研究、探索和实践了安全工程专业本科生实习教学模式,建立了强化工程素质培养... 详细信息

高校本科实习是专业教学计划的重要组成部分,而实习模式是实习效果好坏的关键因素。该文在分析现有实习模式存在问题的基础上,结合专业的办学定位和专业特色,研究、探索和实践了安全工程专业本科生实习教学模式,建立了强化工程素质培养的实习教学构架,更新丰富了实习教学内容,建立完善了实习考核体系,并明确了实习不同环节的评价指标及其权重,从而提高了实习的质量与效果。实践表明,实习模式的更新收到了很好的效果,学生的创新和动手能力显著提高。

关键词：安全工程实习教学模式质量监控体系

偏置式激光头激光加工单点指向功能实现方法的探讨

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电加工与模具 2012年第2期 43-45页

作者：迟关心顾明江王励勤邢振宏刘振堂哈尔滨工业大学机电学院黑龙江哈尔滨150001 济南铸造锻压机械研究所有限公司山东济南250022

对在配置偏置式激光头的激光加工机上实现单点指向功能进行了探讨。为保证激光加工的高速和稳定性,提出分别为程序控制和手控盒控制设计独立的单点指向补偿器P和J的思想,并分析了各自补偿器的实现方法。同时,为了保证单点指向功能的有... 详细信息

对在配置偏置式激光头的激光加工机上实现单点指向功能进行了探讨。为保证激光加工的高速和稳定性,提出分别为程序控制和手控盒控制设计独立的单点指向补偿器P和J的思想,并分析了各自补偿器的实现方法。同时,为了保证单点指向功能的有效实现,还进行了粗插补精度的计算。

关键词：激光加工偏置式激光头单点指向功能

Body mass index and clinical outcomes in patients with intracerebral haemorrhage:results from the China Stroke Center Alliance

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Stroke & Vascular Neurology 2021年第3期6卷 424-432,I0054-I0057页

作者： zhentang Cao Xinmin liu Zixiao Li Hongqiu Gu Yingyu Jiang Xingquan Zhao Yongjun Wang Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Disease BeijingChina

Background and aim Obesity paradox has aroused increasing concern in recent ***,impact of obesity on outcomes in intracerebral haemorrhage(ICH)remains *** study aimed to evaluate association of body mass index(BMI)with in-hospital mortality,complications and discharge disposition in *** Data were from 85705 ICH enrolled in the China Stroke Center Alliance *** were divided into four groups:underweight,normal weight,overweight and obese according to Asian-Pacific *** primary outcome was in-hospital *** secondary outcomes included non-routine discharge disposition and in-hospital *** to graded II or III hospital,community hospital or rehabilitation facilities was considered non-routine *** logistic regression analysed association of BMI with *** 82789 patients with ICH were included in the final ***(OR=2.057,95%CI 1.193 to 3.550)patients had higher odds of in-hospital mortality than those with normal weight after adjusting for covariates,but no significant difference was observed for patients who were overweight or *** significant association was found between BMI and *** was associated with increased odds of several complications,including pneumonia(OR 1.343,95%CI 1.138 to 1.584),poor swallow function(OR 1.351,95%CI 1.122 to 1.628)and urinary tract infection(OR 1.532,95%CI 1.064 to 2.204).Moreover,obese patients had higher odds of haematoma expansion(OR 1.326,95%CI 1.168 to 1.504),deep vein thrombosis(OR 1.506,95%CI 1.165 to 1.947)and gastrointestinal bleeding(OR 1.257,95%CI 1.027 to 1.539).Conclusions In patients with ICH,being underweight was associated with increased in-hospital *** underweight and obese can both increased risk of in-hospital complications compared with having normal weight.

关键词： patients routine mortality

Chalcocite(bio)hydrometallurgy-current state,mechanism,and future directions:A review

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Chinese Journal of Chemical Engineering 2022年第1期35卷 109-120页

作者： Shichao Yu Rui Liao Baojun Yang Chaojun Fang zhentang Wang Yuling liu Baiqiang Wu Jun Wang Guanzhou Qiu School of Minerals Processing&Bioengineering Central South UniversityChangsha 410083China Key Lab of Biohydrometallurgy of Ministry of Education Changsha 410083China College of Chemistry and Chemical Engineering Henan Polytechnic UniversityJiaozuo 454000China Wanbao Mining Ltd. Beijing 100053China

There has been a strong interest in technologies suited for mining and processing of low-grade ores because of the rapid depletion of mineral resources in the *** most cases,the extraction of copper from such raw materials is achieved by applying the leaching ***,its low extraction efficiency and the long extraction period limit its large-scale commercial applications in copper recovery,even though bioleaching has been widely employed commercially for heap and dump bioleaching of secondary copper sulfide *** the technical challenges requires a better understanding of leaching kinetics and on-site microbial ***,this paper reviews the current status of main commercial biomining operations around the world,identifies factors that affect chalcocite dissolution both in chemical leaching and bioleaching,summarizes the related kinetic research,and concludes with a discussion of two on-site chalcocite heap leaching ***,the challenges and innovations for the future development of chalcocite hydrometallurgy are presented in the end.

关键词： Chalcocite Bioleaching Heap leaching Kinetics Copper sulfides Hydrometallurgy

Venturi tube application in high power test of the SRF module

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Nuclear Science and Techniques 2009年第3期20卷 129-132页

作者： MA Guangming liu Jianfei HOU Hongtao MA Zhenyu FU Zechuan ZHANG Zhigang ZHAO zhentang Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Shanghai Key Lab. of Cryogenics ＆ Superconducting RF Technology Shanghai 201800 China

In the superconducting RF module, the dissipation power of the niobium cavity is an important parameter. In the Superconducting radio frequency (SRF) module's acceptance test at Shanghai Synchrotron Radiation Facility (SSRF), the Venturi tube is used to measure the quality factor of SRF cavity at 4.2 K. During the test, the venturi tube is be calibrated by increasing heat load with internal heater. In this paper, the horizontal test principle and venturi effect are briefly introduced. The authors find out a correct way to calibrate the venturi tubes, the calibration results are presented here. From the calibration results, one can deduce the static loss of each module, the source of static loss is also analyzed.

关键词：文氏管加热器核技术研究