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A Novel Pregnane Glycoside from Biondia chinensis

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Chinese Chemical Letters 2003年第10期14卷 1027-1028页

作者： xing gen tan, Shu Lin PENG, Xun LIAO, Jian LIANG, Li Sheng DING Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041 Chengdu Institute of Biology Chinese Academy of Sciences Chengdu 610041 China

A novel pregnane glycoside, biondianoside E, was isolated from the roots of Biondia chinensis. By the spectroscopic and chemical methods, this structure was elucidated as 3B, 5B, 14B, 205, 21-pentahydroxypregnane 3-O-... 详细信息

关键词： Biondia chinensis pregnane glycoside biondianoside E.

Robotic versus laparoscopic surgery for sporadic benign insulinoma:Short-and long-term outcomes

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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 399-405页

作者： Zhu-Zeng Yin Yuan-xing Gao Zhi-Ming Zhao Ming-gen Hu Wen-Bo tang Rong Liu Faculty of Hepato-Pancreato-Biliary Surgery The First Medical CenterChinese PLA General HospitalBeijing 100853China Institute of Hepatobiliary Surgery of Chinese PLA Beijing 100853China Key Laboratory of Digital Hepatobiliary Surgery of Chinese PLA Beijing 100853China

Background:Minimally invasive surgery is the optimal treatment for *** present study aimed to compare short-and long-term outcomes of laparoscopic and robotic surgery for sporadic benign ***:A retrospective analysis of patients who underwent laparoscopic or robotic surgery for insulinoma at our center between September 2007 and December 2019 was *** demographic,perioperative and postoperative follow-up results were compared between the laparoscopic and robotic ***:A total of 85 patients were enrolled,including 36 with laparoscopic approach and 49 with robotic *** was the preferred surgical ***-nine patients(69.4%)underwent enucleation;among them,26 and 33 patients underwent laparoscopic and robotic surgery,*** enucleation had a lower conversion rate to laparotomy(0 vs.19.2%,P=0.013),shorter operative time(102.0 vs.145.5 min,P=0.008)and shorter postoperative hospital stay(6.0 vs.8.5 d,P=0.002)than laparoscopic *** were no differences between the groups in terms of intraoperative blood loss,the rates of postoperative pancreatic fistula and *** a median follow-up of 65 months,two patients in the laparoscopic group developed a functional recurrence and none of the patients in the robotic group had a ***:Robotic enucleation can reduce the conversion rate to laparotomy and shorten operative time,which might lead to a reduction in postoperative hospital stay.

关键词： Robotic surgical procedures Laparoscopy Insulinoma Enucleation Pancreatectomy

Depositional model of the Member Deng-2 marginal microbial mound-bank complex of the Dengying Formation in the southwestern Sichuan Basin, SW China: Implications for the Ediacaran microbial mound construction and hydrocarbon exploration

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Petroleum Science 2024年第2期21卷 806-822页

作者： Jin-Min Song Xin Jin Zhong Luo Shu-gen Liu Shao-Bo Liu xing-Zhi Ma Zhi-Wu Li Xue-Song Lu Ling-Li Zhao Ke-Ran Li Jia-Xin Ren Li-Zhou Tian Hao-Shuang Deng State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu610059SichuanChina PetroChina Research Institute of Petroleum Exploration and Development Beijing100083China Xihua University Chengdu610039SichuanChina

Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China,where the depositional process is regarded confusing. The microfacies, construction types, and depositional model of the Member Deng-2 marginal microbial mound-bank complex have been investigated using unmanned aerial vehicle photography, outcrop section investigation, thin section identification,and seismic reflections in the southwestern Sichuan Basin. The microbialite lithologic textures in this region include thrombolite, dendrolite, stromatolite, fenestral stromatolite, spongiostromata stone,oncolite, aggregated grainstone, and botryoidal grapestone. Based on the comprehensive analysis of“depositional fabrics-lithology-microfacies”, an association between a fore mound, mound framework,and back mound subfacies has been proposed based on water depth, current direction, energy level and lithologic assemblages. The microfacies of the mound base, mound core, mound flank, mound cap, and mound flat could be recognized among the mound framework subfacies. Two construction types of marginal microbial mound-bank complex have been determined based on deposition location, mound scale, migration direction, and sedimentary facies association. Type Jinkouhe microbial mound constructions(TJMMCs) develop along the windward margin owing to their proximity to the seaward subfacies fore mound, with a northeastwardly migrated microbial mound on top of the mud mound,exhibiting the characteristics of large-sized mounds and small-sized banks in the surrounding area. Type E'bian microbial mound constructions(TEMMCs) primarily occur on the leeward margin, resulting from the presence of onshore back mound subfacies, with the smaller southwestward migrated microbial mounds existing on a thicker microbial flat. The platform margin microbial mound depositional model can be correlated with certain late

关键词： Sichuan Basin The Member Deng-2 Marginal microbial mound-bank complex Depositional model Exploration implications

Anisotropic s-Wave Gap in the Vicinity of a Quantum Critical Point in Superconducting BaFe_(2)(As_(1-x)P_(x))_(2) Single Crystals:A Study of Point-Contact Spectroscopy

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Chinese Physics Letters 2024年第4期41卷 118-123页

作者：詹红星林玉尺赵宇清左海艳王兴玉马肖燕李春红罗会仟陈根富李世亮任聪 School of Physics and Astronomy Yunnan UniversityKunming 650500China Beijing National Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of SciencesBeijing 100190China Yunnan Key Laboratory for Electromagnetic Materials and Devices Yunnan UniversityKunming 650500China

We report on soft c-axis point-contact Andreev reflection(PCAR)spectroscopy combining with resistivity measurements on BaFe_(2)(As_(0.7)P_(0.3))_(2),to elucidate the superconducting gap structure in the vicinity of the quantum critical point.A double peak at the gap edge plus a dip feature at zero-bias has been observed on the PCAR spectra,indicative of the presence of a nodeless gap in BaFe_(2)(As_(0.7)P_(0.3))_(2).Detailed analysis within a sophisticated theoretical model reveals an anisotropic gap with deep gap *** PCARs also feature additional structures related to the electron-bosonic coupling *** the extracted superconducting energy gap value,a characteristic bosonic energy Ω_(b) and its temperature dependence are obtained,comparable with the spin-resonance energy observed in neutron scattering *** results indicate a magnetism-driven quantum critical point in the BaFe_(2)(As_(1-x)P_(x))_(2) system.

关键词： quantum critical resistivity

基于Gazebo的深海网箱洗网机器人动力学仿真平台搭建

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南方水产科学 2024年第1期20卷 1-10页

作者：邢旺黄小华李根庞国良袁太平浙江海洋大学浙江舟山316022 中国水产科学研究院南海水产研究所/农业农村部外海渔业可持续利用重点实验室/广东省网箱工程技术研究中心广东广州510300 三亚热带水产研究院海南三亚572024

深海网箱养殖是重要的海水养殖模式,网箱网衣的定期清洗是确保养殖质量和安全的关键环节。目前,网衣普遍采用人工清洗,不仅费时费力,且随着深海网箱规格越来越大,人工方式难度显著提升。洗网机器人为深海网箱网衣清洗提供了更加安全、... 详细信息

深海网箱养殖是重要的海水养殖模式,网箱网衣的定期清洗是确保养殖质量和安全的关键环节。目前,网衣普遍采用人工清洗,不仅费时费力,且随着深海网箱规格越来越大,人工方式难度显著提升。洗网机器人为深海网箱网衣清洗提供了更加安全、便捷的方式;然而,洗网机器人在贴网清洁和水下穿梭过程中,受力难建模、状态难观测,设计抗扰动能力强、能耗低的控制器困难,开展全面实验及数据记录成本高、时间长。针对上述问题,在物理仿真环境Gazebo的基础上,考虑了推进器和洗盘的存在,并分析了在水下环境中诸如附加质量、阻尼等各项水动力学特性以及流场环境等因素对洗网机器人的影响,构建了一套洗网机器人仿真系统,使得洗网机器人水下工作完备数据易获得、控制性能易验证、模型性能易对比,从而助力洗网机器人的控制器开发。

关键词：洗网机器人深海网箱 Gazebo 运动仿真水动力建模

维普期刊数据库博看期刊

Zn,Mg和Mn对7N01合金组织和性能的影响

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稀有金属 2024年第5期48卷 660-670页

作者：王帅罗兵辉邢莎莎姜根魏鑫鹏莫文峰安康学院化学化工学院陕西安康725000 中南大学材料科学与工程学院湖南长沙410083 安康学院医学院陕西安康725000 中联重科科技发展有限公司湖南长沙410083

设计了6种不同成分配比的7N01合金,通过硬度计和万能试验机对不同成分合金在时效过程中的硬度和力学性能进行了测试。分别通过透射电镜明场像(BFTEM)、选区电子衍射(SAED)和高角度环形暗场像(HAADF-STEM)3种不同的成像模式,对不同配比... 详细信息

设计了6种不同成分配比的7N01合金,通过硬度计和万能试验机对不同成分合金在时效过程中的硬度和力学性能进行了测试。分别通过透射电镜明场像(BFTEM)、选区电子衍射(SAED)和高角度环形暗场像(HAADF-STEM)3种不同的成像模式,对不同配比合金的微观组织进行了表征和分析。结果表明:在120℃峰时效过程中,Mg对合金晶内GP区和η′相的类型、数量有明显的影响;Zn对时效过程中晶界无沉淀析出带(PFZ)变化有明显的影响;Zn和Mg共同影响着晶内和晶界析出相的尺寸和密度。Mn对Al6Mn析出相的数量和分布影响较大,同时Mn含量增大会略微提高合金晶内GP区和η′相的密度。

关键词： 7N01合金成分配比硬度力学性能析出相演变

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37kV环氧树脂干式变压器设计与分析

机械设计与制造 2024年第5期399卷 249-252页

作者：田兴国刁燕苗虹张根莱四川大学机械工程学院四川成都610065 四川大学电气工程学院四川成都610065

根据干式变压器损耗和绝缘等级等要求,提出一种绕组各层匝数非均匀分布的新型37 kV环氧树脂干式变压器结构。该新型结构铁芯采用长圆形截面45°全斜五步进错位搭接结构;低压绕组共四层,内三层各一匝铜箔,第四层三匝铜箔;高压绕组共两层... 详细信息

根据干式变压器损耗和绝缘等级等要求,提出一种绕组各层匝数非均匀分布的新型37 kV环氧树脂干式变压器结构。该新型结构铁芯采用长圆形截面45°全斜五步进错位搭接结构;低压绕组共四层,内三层各一匝铜箔,第四层三匝铜箔;高压绕组共两层,每层12段。采用ANSYS Maxwell和ANSYS Fluent分别对干式变压器进行电磁场、温度场的仿真分析,得到干式变压器铁损曲线和温度分布云图。仿真结果表明干式变压器的空载损耗为4.5561kW,在室温、额定工况不开风机运行时温升为95K,以15%的过载系数在室温开风机运行时温升为87K,经验证该结构完全满足空载损耗8 000W和F级绝缘等级的要求。

关键词：干式变压器电磁场损耗温度场温升

Sorption of pyrene on two paddy soils and their particle-size fractions

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Journal of Environmental Sciences 2005年第6期17卷 962-965页

作者： LI Jiu-hai PAN gen-xing Institute of Resources Ecosystem and Environment of Agriculture Nanjing Agricultural University Nanjing 210095 China

In the present study, the sorption of pyrene on two kinds of bulk paddy soils, Gleyic Stagnic Anthrosols, and Ferric accumulic Stagnic Anthrosols as well as their particle-size fractions was investigated. The sorption isotherms fitted well with Freundlich equation. For both soils, the clay fraction（〈 2μm） and coarse sand fraction（2000-250μm） had higher sorption capacity than fine sand fraction（250-20 μm） and silt fraction（20-2 μm）. The IogKoc values obtained of each soil and its particle-size fractions were similar, proving that SOM content was a key factor affecting pyrene sorption. The Kd values showed a significant correlation with contents of dithionite-extractable Fe in both paddy soils and a good relationship with CEC in Gleyic Stagnic Anthrosols, indicating possible effects of surface properties of particle-size fractions on the sorption of pyrene.

关键词： paddy soil particle-size fraction PAHs sorption

AFM Study on Reliability of Nanoscale DLC Films Deposited by ECR-MPCVD

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材料热处理学报 2004年第5B期25卷 1260-1262页

作者： ZHUShou-xing ZHUShi-gen DINGJian-ning SchoolofMechanicalEngineering DonghuaUniversityShanghai200051China Micro／NanoScienceandTechnologyCenter JiangsuUniversityZhenjiang212013China

Nanoindentation, scratch and wear tests based on an atomic force microscope (AFM) were carried out to study the reliability of diamond-like carbon (DLC) films, deposited by electron cyclotron resonance microwave plasma chemical vapor deposition (ECR-MPCVD). The predictors for film reliability were given to investigate the resistance of DLC films to indent, scratch, and wear. Experimental results showed that the films at 64.9nm and 12.07nm exhibited better reliability than thin one at 2.78nm, 4.48nm. In addition, the reliability strength of films above 12.07nm went stable, and the films showed good performance of anti-indentation, and-scratch and anti-wear. Finally, size effect of nanoscale monolayer film was introduced to explain the reliability of nanoscale DLC films.

关键词： AFM DLC ECR-MPCVD 刻痕磨损性能不定形碳