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Journal of Palaeogeography 2019年第4期8卷 360-367页

作者： Ting Gao Da-Qing li long-feng li Jing-Tao Yang Institute of Vertebrate Paleontology and College of life Science and Technology Gansu Agricultural University

Plesiosaurs are one of the common groups of aquatic reptiles in the Mesozoic,which mainly lived in marine *** plesiosaurs are rare in the world,especially from the *** present paper reports the first freshwater plesiosaur,represented by four isolated teeth from the Middle Jurassic fluviolacustrine strata of Qingtujing area,Jinchang City,Gansu Province,Northwest *** teeth are considered to come from one *** comparative analysis of the corresponding relationship between the body and tooth sizes of the known freshwater plesiosaur shows that Jinchang teeth represent a small-sized *** on the adaptive radiation of plesiosaurs and the palaeobiogeographical context,we propose a scenario of a river leading to the Meso-Tethys in the Late Middle Jurassic in Jinchang area,which may have provided a channel for the seasonal migration of plesiosaurs.

关键词： Freshwater plesiosaur Middle Jurassic Jinchang Gansu Province Palaeobiogeography

The first theropod tracks from the Middle Jurassic of Gansu,Northwest China:new and rare evidence of quadrupedal progression in theropod dinosaurs

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Journal of Palaeogeography 2019年第2期8卷 198-208页

作者： Da-Qing li li-Da Xing Martin G.Lockley Anthony Romilio Jing-Tao Yang long-feng li Institute of Vertebrate Paleontology and College of life Science and Technology Gansu Agricultural University School of Earth Sciences and Resources China University of Geosciences(Beijing) State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences(Beijing) Dinosaur Trackers Research Group University of Colorado Denver School of Biological Sciences The University of Queensland

A new Middle Jurassic tracksite dominated by non-avian theropod footprints from the Wangjiashan Formation in Pingchuan District,Baojishan Basin,Gansu Province has yielded a unique trackway with four consecutive manus-pes *** three previous examples,all Early Jurassic in age,of theropod trackways are known with convincing examples of manus tracks and in each case,only two tracks were recorded in association with pes tracks with metatarsal impressions and pelvic traces indicating crouching ***,this is the first example of manus tracks registered while a theropod trackmaker was *** unique configuration is here designated as Grallator pingchuanensis *** shows the trackmaker forelimbs registering in a wide straddle gait,much wider than the pes trackway *** confirms previous reports that theropods could occasionally register tridactyl,ectaxonic manus *** the case of the Pingchuan trackway,the short step indicates an animal moving at a slow speed,probably due to a soft substrate.

关键词： Wangjiashan Formation Grallatorid Grallator Theropods Dinosaur tracks

Do Different Cyclooxygenase Inhibitors Impair Rotator Cufl Healing in a Rabbit Model？

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Chinese Medical Journal 2015年第17期128卷 2354-2359页

作者： Yi Lu Yue li feng-long li Xu li Hong-Wu Zhuo Chun-Yan Jiang Department of Sports Medicine Service Beijing Jishuitan Hospital Beijing 100035 China

Background： The effect of selective and non-selective cyclooxygenase （COX） inhibitors on tendon healing was variable. The purpose of the study was to evaluate the influence of non-selective COX inhibitor, ibuprofen and flurbiprofen axetil and selective COX-2 inhibitor, celecoxib on the tendon healing process in a rabbit model. Methods： Ninety-six New Zealand rabbits were used as rotator cuff repair models. After surgery, they were divided randomly into four groups： Ibuprofen （10 mg·kg^-1·d^-1）, celecoxib （8 mg·kg^-1·d^-1）, flurbiprofen axetil （2 mg·kg^-1·d^-1）, and control group （blank group）. All drugs were provided for 7 days. Rabbits in each group were sacrificed at 3, 6, and 12 weeks after tendon repair. Tendon biomechanical load failure tests were performed. The percentage of type I collagen on the bone tendon insertion was calculated by Pieric acid Sirius red staining and image analysis. All data were compared among the four groups at the same time point. All data in each group were also compared across the different time points. Qualitative histological evaluation of the bone tendon insertion was also performed among groups. Results： The load to failure increased significantly with time in each group. There were significantly lower failure loads in the celecoxib group than in the control group at 3 weeks （0.533 vs. 0.700, P = 0.002）, 6 weeks （0.607 vs. 0.763, P = 0.01）, and 12 weeks （0.660 vs. 0.803, P = 0.002）, and significantly lower percentage of type I collagen at 3 weeks （11.5% vs. 27.6%, P 0.001）, 6 weeks （40.5% vs. 66.3%, P = 0.005）, and 12 weeks （59.5% vs. 86.3%, P = 0.001）. Flurbiprofen axetil showed significant differences at 3 weeks （failure load： 0.600 vs. 0.700, P = 0.024; percentage of type I collagen： 15.6% vs. 27.6%, P = 0.001）, but no significant differences at 6 and 12 weeks comparing with control group, whereas the ibuprofen groups did not show any significant difference at each time point. Conclusions： Nonsteroidal anti-inflammatory drugs

关键词： Biomechanical Cyclooxygenase lnhibitors Healing Histological Rotator Cuff

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数字电源控制模块的设计

原子能科学技术 2009年第11期43卷 1043-1048页

作者：龙锋利程健中国科学院高能物理研究所北京100049

为加速器高精度磁铁稳流电源设计了数字电源控制模块DPSCM,以硬开关拓扑结构的磁铁电源作为被控对象,实现电源的全数字化控制。DPSCM以现场可编程门阵列FPGA为控制部件,实现对高精度ADC和DAC的控制,由数字调节器产生高精度数字脉宽调制... 详细信息

为加速器高精度磁铁稳流电源设计了数字电源控制模块DPSCM,以硬开关拓扑结构的磁铁电源作为被控对象,实现电源的全数字化控制。DPSCM以现场可编程门阵列FPGA为控制部件,实现对高精度ADC和DAC的控制,由数字调节器产生高精度数字脉宽调制信号,并实现电源的逻辑控制和联锁保护功能。通过模拟负载测试了DPSCM的基本功能,并在数字电源样机上测试了DPSCM长期运行的可靠性及稳定性,样机电源连续运行72 h,电流稳定度优于5×10-5。

关键词：数字电源控制模块现场可编程门阵列数字调节器高精度数字脉宽调制信号模拟负载

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基于现场可编程门阵列的数字调节器设计

原子能科学技术 2009年第9期43卷 780-784页

作者：龙锋利程健中国科学院高能物理研究所北京100049

根据磁铁稳流电源闭环控制的基本原理,将模拟调节器及相关的外围控制电路采用全数字化控制技术,并通过嵌入数字信号处理模块的现场可编程门阵列(FPGA)来实现,设计了数字调节器(DRL)。通过样机试验证明,该数字调节器可实现对电源的全数... 详细信息

根据磁铁稳流电源闭环控制的基本原理,将模拟调节器及相关的外围控制电路采用全数字化控制技术,并通过嵌入数字信号处理模块的现场可编程门阵列(FPGA)来实现,设计了数字调节器(DRL)。通过样机试验证明,该数字调节器可实现对电源的全数字化调节和控制,满足多数加速器对静态磁铁稳流电源的控制需求。

关键词：加速器磁铁电源闭环控制数字调节器现场可编程门阵列

Effect of partial liquid ventilation on oleic acid-induced inflammatory responses in piglets

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Chinese Medical Journal 2010年第15期123卷 2088-2093页

作者： ZHU Yao-bin WANG Qiang liU Ying-long li Xiao-feng li Jian-an LU Xiao-dong liNG feng liU Ai-jun FAN Xiang-ming Department of Pediatric Cardiac Surgery Center Fu Wai HospitalChinese Academy of Medical Sciences and Peking Union Medical College Beijing 100037 China

Background Pediatric patients are susceptible to lung *** lung injury （Ali） in children often results in a high *** liquid ventilation （PLV） has been shown to markedly improve oxygenation and reduce histologic evidence of injury in a number of lung injury *** study aimed to examine the hypothesis that PLV would attenuate the production of local and systemic cytokines in an immature piglet model of Ali induced by oleic acid （OA）.Methods Twelve Chinese immature piglets were induced to develop Ali by oleic *** animals were randomly assigned to two groups （n=6）：（1） conventional mechanical ventilation （MV） group and （2） PLV with FC-77 （10 ml/kg） *** Compared with MV group, PLV group got better cardiopulmonary variables （P 〈0.05）.These variables included heart rate, mean blood pressure, blood pH, partial pressure of arterial oxygen （PaO2）, PaO2/FiO2 and partial pressure of arterial carbon dioxide （PaCO2）.Partial liquid ventilation reduced IL-1β, IL-6, IL-10 and TN F-α both in plasma and tissue concentrations compared with MV group （P 〈0.05）.Conclusions Partial liquid ventilation provides protective effects against inflammatory responses in the lungs of oleic acid-induced immature piglets.

关键词： acute respiratory distress syndrome partial liquid ventilations inflammatory response cytokine piglets

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加速器磁铁稳流电源的自适应型控制器设计

原子能科学技术 2017年第6期51卷 1116-1122页

作者：疏坤龙锋利韩超中国科学院高能物理研究所北京100049 中国科学院大学北京100049

本文通过在电源数控硬件平台上集成系统辨识模块对被控对象进行辨识,并使用集成于FPGA的软处理器来完成数据处理和参数计算,设计并完成了一种能适应负载变化且参数自整定的智能型控制器,其控制参数自动根据负载特性整定,不需人为干预。... 详细信息

本文通过在电源数控硬件平台上集成系统辨识模块对被控对象进行辨识,并使用集成于FPGA的软处理器来完成数据处理和参数计算,设计并完成了一种能适应负载变化且参数自整定的智能型控制器,其控制参数自动根据负载特性整定,不需人为干预。该控制器已在加速器磁铁电源上进行了测试,其主要技术指标满足使用要求。

关键词：磁铁电源系统辨识优化控制自适应控制器

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功率因数校正的数字化控制

原子能科学技术 2009年第7期43卷 654-657页

作者：江良伟龙锋利程健中国科学院高能物理研究所北京100049

高能加速器的电源系统是加速器最大的电能使用系统,提高加速器的运行效率和经济性一直是电源系统的目标。为提高开关电源的功率因数,在数字化开关稳流电源的基础上,设计了一种功率因数校正(PFC)的数字控制方案。重点阐述了基于硬件描述... 详细信息

高能加速器的电源系统是加速器最大的电能使用系统,提高加速器的运行效率和经济性一直是电源系统的目标。为提高开关电源的功率因数,在数字化开关稳流电源的基础上,设计了一种功率因数校正(PFC)的数字控制方案。重点阐述了基于硬件描述语言(VHDL)的数字控制环的算法、多通道模数转换器(ADC)的控制和脉宽调制(PWM)信号的产生,以及如何将其作为片上系统的用户外设。经测试表明,该方案有效地提高了开关电源的功率因数,达到了预期的设计目标。

关键词：功率因数校正数字化控制现场可编程门阵列片上可编程系统用户外设

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北斗卫星导航系统逆向接收溯源方法

宇航学报 2017年第4期38卷 367-374页

作者：李丹丹许龙霞朱峰李孝辉中国科学院国家授时中心西安710600 中国科学院精密导航定位与定时技术重点实验室西安710600 中国科学院大学北京100049

本文针对现有卫星导航系统溯源方法以及北斗卫星导航系统(BDS)独特的星座结构,提出了逆向接收溯源方法。在中国科学院国家授时中心保持的协调世界时(UTC(NTSC))守时实验室接收北斗卫星导航信号,监测获得每颗北斗卫星广播的系统时间与UTC... 详细信息

本文针对现有卫星导航系统溯源方法以及北斗卫星导航系统(BDS)独特的星座结构,提出了逆向接收溯源方法。在中国科学院国家授时中心保持的协调世界时(UTC(NTSC))守时实验室接收北斗卫星导航信号,监测获得每颗北斗卫星广播的系统时间与UTC(NTSC)的偏差,生成溯源模型参数。研究了溯源模型参数的预报策略,分析不同时长原始数据和不同阶次的预报模型对溯源模型参数预报精度的影响。逆向接收溯源方法通过改变导航电文中的溯源模型参数产生方式,不仅能够实现向协调世界时(UTC)的溯源,而且用户在不进行任何改变的情况下,通过单向接收就可以实现优于5ns的单向授时,该精度与共视精度相当,优于目前的GNSS单向授时方法。将北斗的单向授时精度由十纳秒量级提高到纳秒量级,有利于北斗卫星导航系统的推广应用。

关键词：北斗卫星导航系统溯源模型参数时间偏差 GEO 授时精度

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高精度稳流电源的网络化检测系统

原子能科学技术 2006年第2期40卷 249-251页

作者：龙锋利张旌陈斌程健中国科学院高能物理研究所北京100049

利用24位高精度宽动态范围Δ-Σ模数转换器ADS1210和CAN总线技术,研制了高精度稳流电源网络化检测系统。应用该系统测试了北京正负电子对撞机重大改造工程(BEPCⅡ)的电源工程样机,并与数字电压表的测试结果进行了比较。试验结果表明,该... 详细信息

利用24位高精度宽动态范围Δ-Σ模数转换器ADS1210和CAN总线技术,研制了高精度稳流电源网络化检测系统。应用该系统测试了北京正负电子对撞机重大改造工程(BEPCⅡ)的电源工程样机,并与数字电压表的测试结果进行了比较。试验结果表明,该系统能够满足测试BEPCⅡ高精度稳流电源的需求。

关键词：模数转换器 CAN总线稳定度测试网络化检测