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Application of needle-knife in difficult biliary cannulation for endoscopic retrograde cholangiopancreatography

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Hepatobiliary & Pancreatic Diseases International 2006年第4期5卷 590-594页

作者： Ping-Hong Zhou, Li-Qing Yao, Mei-dong Xu, yun-Shi zhong, Wei-dong Gao, Guo-Jie He, Yi-Qun Zhang, Wei-Feng Chen and Xin-Yu Qin Department of General Surgery, zhongshan Hospital, Fudan University, Shanghai 200032, China Department of General Surgery Zhongshan Hospital Fudan University Shanghai 200032 China. chow@***

BACKGROUND: Getting directly into the common bile duct (CBD) is the most important step for successful therapeutic biliary endoscopy. In 5%-10% of cases, the CBD remains inaccessible, necessitating pre-cut papillotomy or fistulotomy with a needle-knife. The aim of this study was to assess the value of early application of the needle-knife in difficult biliary cannulation for endoscopic retrograde cholangiopancreatography (ERCP). METHODS: Patients with failed biliary cannulation after 10 minutes or guide wire entering the pancreatic tube 3 times were randomly divided into group of needle-knife cut and group of persistent cannulation by standard techniques. The cannulation times, success rates and complication rates were compared between the two groups. RESULTS: A total of 948 therapeutic biliary ERCP procedures were performed between October 2004 and February 2006. Of 91 patients with difficult biliary cannulation, 43 patients underwent needle-knife cut: the cannulation success rate was 90.7%, the mean cannulation time was 5.6 minutes, and the complication rate was 9.3%. The other 48 patients underwent persistent cannulation by standard techniques: the cannulation success rate was 75%, the mean cannulation time was 10.2 minutes, and the complication rate was 14.6%. Significant differences were observed in cannulation success rate and cannulation time but in complication rate between the two ***: The early application of the needle-knife in difficult biliary cannulation is time-saving, safe and effective, with no increase in complication rate.

关键词： endoscopic retrograde cholangiopancreatography needle-knife cannulation

CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

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Journal of Energy Chemistry 2025年第1期100卷 522-532页

作者： Jin-Peng Wang Guo-Cui Mao Hui-Lin Jiang Bao-Xia dong yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-CaO （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

关键词： Metal hydride Ni catalysts Carbonate Metal-carbonate interface

由高双折射光纤环镜构成的可变波长输出的L-波段掺铒光纤激光器

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中国激光 2002年第10期29卷 868-870页

作者：杨石泉蒙红云袁树忠董孝义南开大学现代光学研究所天津300071

报道了一种结构简单的可变波长输出的L 波段线型腔掺铒光纤激光器。其中的波长选择器件为一包括两段高双折射光纤在内的光纤环镜 ,通过调整环镜内偏振控制器的状态可以改变环镜对不同波长的反射率以获得可变波长输出的效果。线型腔内用 ... 详细信息

报道了一种结构简单的可变波长输出的L 波段线型腔掺铒光纤激光器。其中的波长选择器件为一包括两段高双折射光纤在内的光纤环镜 ,通过调整环镜内偏振控制器的状态可以改变环镜对不同波长的反射率以获得可变波长输出的效果。线型腔内用 980nm激光抽运铒光纤产生的ASE作二次抽运源 ,使腔内铒光纤的增益谱由C 波段位移到L 波段。实验中观察到波长在 1 5 83～ 1 6 0 0nm范围内可变的稳定激光输出 ,波长调谐范围为 1

关键词：掺铒光纤激光器高双折射光纤 L-波段光纤环境可变波长输出

工作在L-波段的可调谐环形腔掺铒光纤激光器

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中国激光 2002年第8期29卷 677-679页

作者：杨石泉赵春柳蒙红云袁树忠董孝义南开大学现代光学研究所天津300071

报道了一种波长调谐范围达 4 5nm的L 波段环形腔掺铒光纤激光器。利用偏振调谐的方法 ,可以使该激光器的工作波长在 15 6 0nm到 16 0 5nm范围内调谐 ,调谐范围几乎覆盖了整个L 波段。环形腔内用两段铒光纤作为增益介质 ,采用二次抽运方... 详细信息

报道了一种波长调谐范围达 4 5nm的L 波段环形腔掺铒光纤激光器。利用偏振调谐的方法 ,可以使该激光器的工作波长在 15 6 0nm到 16 0 5nm范围内调谐 ,调谐范围几乎覆盖了整个L 波段。环形腔内用两段铒光纤作为增益介质 ,采用二次抽运方式 ,由一 980nm激光器抽运其中一段铒光纤产生的放大自发辐射作二次抽运源 ,再对腔内的两段铒光纤进行抽运 ,使它们的增益谱位移到L 波段 ,获得稳定的激光输出。

关键词： L-波段可调谐环形腔掺铒光纤激光器光纤通信

Significant loss of soil inorganic carbon at the continental scale

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National Science Review 2022年第2期9卷 13-20页

作者： Xiao-dong Song Fei Yang Hua-Yong Wu Jing Zhang De-Cheng Li Feng Liu Yu-Guo Zhao Jin-Ling Yang Bing Ju Chong-Fa Cai Biao Huang Huai-Yu Long Ying Lu Yue-Yu Sui Qiu-Bing Wang Ke-Ning Wu Feng-Rong Zhang Ming-Kui Zhang Zhou Shi Wan-Zhu Ma Gang Xin Zhi-Ping Qi Qing-Rui Chang En Ci Da-Gang Yuan Yang-Zhu Zhang Jun-Ping Bai Jia-Ying Chen Jie Chen Yin-Jun Chen yun-zhong dong Chun-Lan Han Ling Li Li-Ming Liu Jian-Jun Pan Fu-Peng Song Fu-Jun Sun Deng-Feng Wang Tian-Wei Wang Xiang-Hua Wei Hong-Qi Wu Xia Zhao Qing Zhou Gan-Lin Zhang State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences College of Advanced Agricultural Sciences University of Chinese Academy of Sciences College of Resources and Environment Huazhong Agricultural University Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences College of Natural Resources and Environment South China Agricultural University Northeast Institute of Geography and Agroecology Chinese Academy of Sciences College of Land and Environment Shenyang Agricultural University School of Land Science and Technology China University of Geosciences College of Land Science and Technology China Agricultural University College of Environmental and Resource Sciences Zhejiang University Institute of Digital Agriculture Zhejiang Academy of Agricultural Sciences College of Agriculture Heilongjiang Bayi Agricultural University Tropical Crops Genetic Resources Institute Chinese Academy of Tropical Agricultural Sciences College of Natural Resources and Environment Northwest A & F University College of Resources and Environment Southwest University College of Resources Sichuan Agricultural University College of Resources and Environment Hunan Agricultural University Institute of Agricultural Product Quality Standard and Testing Research Tibet Academy of Agricultural and Animal Husbandry Sciences School of Agricultural Sciences Zhengzhou University Institute of Agriculture Environment and Resources Research Shanxi Academy of Agricultural Sciences College of Resources and Environment Henan Agricultural University College of Resources and Environment China Agricultural University College of Resources and Environmental Sciences Nanjing Agricultural University College of Resources and Environment Shandong Agricultural University Agricultural College Guangxi University College of Grassland and Environment Science Xinjiang Agricultural University College of Geographical Science Qinghai Normal University

Widespread soil acidification due to atmospheric acid deposition and agricultural fertilization may greatly accelerate soil carbonate dissolution and ***,to date,few studies have addressed these ***,we use meta-analysis and nationwide-survey datasets to investigate changes in soil inorganic carbon(SIC) stocks in *** observe an overall decrease in SIC stocks in topsoil(0-30 cm)(11.33 g C m-2yr-1) from the 1980 s to the 2010 *** SIC stocks have decreased by～8.99±2.24%(1.37±0.37 Pg C).The average SIC losses across China(0.046 Pg C yr-1) and in cropland(0.016 Pg C yr-1) account for～17.6%-24.0% of the terrestrial C sink and 57.1% of the soil organic carbon sink in cropland,*** deposition and climate change have profound influences on SIC *** estimate that～19.12%-19.47% of SIC stocks will be further lost by *** consumption of SIC may offset a large portion of global efforts aimed at ecosystem carbon sequestration,which emphasizes the importance of achieving a better understanding of the indirect coupling mechanisms of nitrogen and carbon cycling and of effective countermeasures to minimize SIC loss.

关键词： China soil inorganic carbon stocks global change carbonate soil acidification

Process and properties of electroless Ni-W-B amorphous electrical resistance film

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 144-146页

作者： ZHU Xiao-yun GUO zhong-cheng XU Rui-dong The Centre of New Materials and Surface Engineering Research and Development Kunming University of Science and Technology Kunming 650093 China The Centre of New Materials and Surface Engineering Research and DevelopmentKunming University of Science and Technology Kunming 650093 China The Centre of New Materials and Surface Engineering Research and DevelopmentKunming University of Science and Technology Kunming 650093 China

The process and properties of electroless plating Ni-W-B alloy have been studied. The results show that the deposits containing W and B are obtained, and the deposition rate of the bath is increased with increase of W content when a certain amount of sodium tungstate solution is added in the Ni-B bath. The Ni-W-B alloy is amorphous as deposition and its resistivity increases directly with the increase of W content in the coating, but decreases gradually with increasing the deposit thickness. XRD and SEM show that the distributions of W and B in the Ni-W-B alloy film are very uniform and dispersed without any segregation.

关键词： electroless Ni-W-B alloy electrical resistance film properties

Effects of pulse current on properties of electrodeposited RE-Ni-W-P-SiC composite coating

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 140-143页

作者： GUO zhong-cheng ZHU Xiao-yun XU Rui-dong Center of Materials and Surface Engineering Research and Development Kunming University of Science and Technology Kunming 650093 China Center of Materials and Surface Engineering Research and DevelopmentKunming University of Science and Technology Kunming 650093 China Center of Materials and Surface Engineering Research and DevelopmentKunming University of Science and Technology Kunming 650093 China

Effects of pulse current on properties of electrodeposited RE-Ni-W-P-SiC composite coating were studied. The results show that hardness of the pulse current electrodeposited composite coatings is higher than that of the direct current electrodeposited composite coatings while other parameters are the same. Otherwise, the deposited velocity is higher, and wear resistance and corrosion resistance of the pulse current electrodeposited composite coatings are also improved when the average current density is 10 A/dm2 , pulse frequency is 800 Hz and duty ratio is 1: 5. The hardness of the coating as-deposited is HV500 - 700, and it reaches HV1300 after heat treatment at 400 ℃ for 1 h.

关键词： RE-Ni-W-P-SiC composite coating pulse current electrodeposition properties

Numerical simulation of slurry jets using mixture model

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Water Science and Engineering 2013年第1期6卷 78-90页

作者： Wen-xin HUAI Wan-yun XUE zhong-dong QIAN State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University

Slurry jets in a static uniform environment were simulated with a two-phase mixture model in which flow-particle interactions were considered. A standard k-e turbulence model was chosen to close the governing equations. The computational results were in agreement with previous laboratory measurements. The characteristics of the two-phase flow field and the influences of hydraulic and geometric parameters on the distribution of the slurry jets were analyzed on the basis of the computational results. The calculated results reveal that if the initial velocity of the slurry jet is high, the jet spreads less in the radial direction. When the slurry jet is less influenced by the ambient fluid （when the Stokes number St is relatively large）, the turbulent kinetic energy k and turbulent dissipation rate e, which are relatively concentrated around the jet axis, decrease more rapidly after the slurry jet passes through the nozzle. For different values of St, the radial distributions of streamwise velocity and particle volume fraction are both self-similar and fit a Gaussian profile after the slurry jet fully develops. The decay rate of the particle velocity is lower than that of water velocity along the jet axis, and the axial distributions of the centerline particle streamwise velocity are self-similar along the jet axis. The pattern of particle dispersion depends on the Stokes number St. When St = 0.39, the panicle dispersion along the radial direction is considerable, and the relative velocity is very low due to the low dynamic response time. When St = 3.08, the dispersion of particles along the radial direction is very little, and most of the particles have high relative velocities along the streamwise direction.

关键词： slurry jet," numerical simulation," two-phase mixture model Stokes number,"flow-particle interaction

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库车依南2井包裹体形成的古温度古压力

新疆石油地质 2004年第4期25卷 369-371页

作者：刘中云王东风肖贤明刘德汉中国科学院广州地球化学研究所有机地球化学国家重点实验室广东广州510640

塔里木库车坳陷依南2井侏罗系储集层砂岩中流体包裹体较丰富,主要发育有石油包裹体,盐水溶液包裹体及气态烃包裹体。石油包裹体均一温度为85-110℃,盐水溶液包裹体均一温度为90～120℃与128-168℃,分别与石油包裹体及气态烃包裹体共生... 详细信息

塔里木库车坳陷依南2井侏罗系储集层砂岩中流体包裹体较丰富,主要发育有石油包裹体,盐水溶液包裹体及气态烃包裹体。石油包裹体均一温度为85-110℃,盐水溶液包裹体均一温度为90～120℃与128-168℃,分别与石油包裹体及气态烃包裹体共生。模拟计算出典型石油包裹体与气态烃包裹体的捕获温度与捕获压力分别为115℃,35.9MPa及162℃,54.8MPa.结合成藏地质背景,推测石油包裹体形成时间为12×106-10×106a,气态烃包裹体形成时间为7×106-6×106a,石油包裹体来源干阳霞凹陷侏罗系煤系烃源岩,气态烃包裹体源于依南2井区侏罗系煤系烃源岩。

关键词：流体包裹体古温度古压力成藏地质塔里木盆地