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深水采油树井口液压连接器的设计

船海工程 2024年第3期53卷 113-119页

作者：李华张崇黄青松任冠龙汪洋余意重庆前卫科技集团有限公司工程事业部重庆401121

设计一种基于18-3/4"H4型面、69 MPa井口压力的液压驱动锁块式连接器,通过有限元方法分析锁紧型面过盈量对锁紧峰值压力、连接器预紧力的影响,预紧力与锁紧峰值压力之间的关系,以及VX钢圈在失效负载条件下的密封性能,并对相关分析结果... 详细信息

设计一种基于18-3/4"H4型面、69 MPa井口压力的液压驱动锁块式连接器,通过有限元方法分析锁紧型面过盈量对锁紧峰值压力、连接器预紧力的影响,预紧力与锁紧峰值压力之间的关系,以及VX钢圈在失效负载条件下的密封性能,并对相关分析结果进行测试验证。分析及测试验证表明,在过盈量可调范围内连接器预紧力与锁紧峰值压力为线性关系,可通过锁紧峰值压力的大小有效评估预紧力;有限元分析结果可为连接器的调试作参考;连续的环状接触压痕是钢圈密封的必要条件,密封面的材料及加工质量是建立密封的关键因素;连接器在69 MPa+1300 kN+11000 kN·m负载条件下功能、结构及密封性能良好。连接器搭载采油树在南海相关油气田得到成功的示范应用。

关键词：水下采油树井口液压连接器密封钢圈锁紧峰值压力预紧力负载测试

Prognostic Value of ALP and LDH in Periampullary Carcinoma Patients Undergoing Surgery

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Current Medical Science 2022年第1期42卷 150-158页

作者： Chao DANG Yun-hua DENG ren-yi QIN Department of Pancreatic-Biliary Surgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Dermatology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective:Conversion of normal cells to cancer cells is often accompanied by abnormal synthesis of serum *** alkaline phosphatase(ALP)and lactate dehydrogenase(LDH)have been reported to have prognostic value in a variety of *** aim of this study was to investigate the effect of preoperative serum ALP and LDH levels on the prognosis of patients with periampullary carcinoma who underwent pancreatoduodenectomy(PD).

关键词： periampullary malignancy pancreatoduodenectomy alkaline phosphatase lactate dehydrogenase prognostic value

Superconductivity in kagome metal ThRu_(3)Si_(2)

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Chinese Physics B 2024年第5期33卷 36-41页

作者：刘艺厉静杨武璋卢佳依曹博雅李华旬柴万力武思祺李佰卓孙云蕾焦文鹤王操许晓峰任之曹光旱 School of Physics Zhejiang UniversityHangzhou 310058China Department of Applied Physics Zhejiang University of TechnologyHangzhou 310023China School of Science Westlake Institute for Advanced StudyWestlake UniversityHangzhou 310064China Department of Physics Shandong University of TechnologyZibo 255049China School of Information and Electrical Engineering Zhejiang University City CollegeHangzhou 310015China Interdisciplinary Center for Quantum Information and State Key Laboratory of Silicon and Advanced Semiconductor MaterialsZhejiang UniversityHangzhou 310058China Collaborative Innovation Centre of Advanced Microstructures Nanjing UniversityNanjing 210093China

We report the physical properties of ThRu_(3)Si_(2)featured with distorted Ru kagome *** combined experiments of resistivity,magnetization and specific heat reveal bulk superconductivity with T_(c)=3.8 *** specific heat jump and calculated electron–phonon coupling indicate a moderate coupled BCS *** comparison with LaRu_(3)Si_(2),the calculated electronic structure in ThRu_(3)Si_(2)shows an electron-doping effect with electron filling lifted from 100 meV below flat bands to 300 meV above *** explains the lower superconducting transition temperature and weaker electron correlations observed in ThRu_(3)Si_(2).Our work suggests the Tc and electronic correlations in the kagome superconductor could have an intimate connection with the flat bands.

关键词： superconductivity kagome lattice flat band

Effect of mechanical vibration process parameters on the cement plugs properties for abandoned wells

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Petroleum Science 2023年第4期20卷 2428-2441页

作者： Hang-Ming Liu Yang-Ye he Ji-Fang Wan Lin Chen Xian-Zhong yi Yuan-hua Zhou Yu-Xian he Xiang-Gui Ming Lu ren Cooperative Innovation Center of Unconventional Oil and Gas Yangtze University(Ministry of Education&Hubei Province)WuhanHubei430100China School of Mechanical Engineering Yangtze UniversityJingzhouHubei434023China CNPC Engineering Technology R&D Company Limited Beijing102206China College of Safety and Ocean Engineering China University of Petroleum-BeijingBeijing102249China Engineering Technology Research Institute CNPC Bohai Drilling Engineering Co.Ltd.Tianjin300457China

A high-quality plug of the abandoned wellbore is considered an essential technical aspect of the oil and gas well abandonment technology system. This paper presents a method of active mechanical excitation to enhance the quality of wellbore plug barriers. An indoor simulation platform is developed, and the effects of different combinations of vibration frequency, amplitude and duration on the properties of the wellbore plug cement material are investigated. It is observed that the optimal combination of excitation parameters occurs at a vibration frequency of 15 Hz, a vibration time of 6 min, and a vibration amplitude of 3 mm. Compared with the condition without the vibration process, the cementing strength, compressive strength, and tensile strength of wellbore cement plug with the optimal mechanical vibration process could increase by 51%, 38% and 20%, respectively, while the porosity decreases by 5%. As determined by scanning electron microscopy of the set cement's microstructure, mechanical vibration effectively eliminates internal porosity and improves the set cement's density. The optimal excitation parameters obtained from the test can guide the design of the vibration plugging tool. The designed vibration plugging tool is simulated in the near field. The cement plug cementation quality tester tests the vibrating and non-vibrating samples, and the cementation ratio is calculated. The test results show that the average cementation ratio of vibrating samples is 0.89375, and that of non-vibrating samples is 0.70625, and the cementation quality is improved by 27%. It is concluded that it not only provides essential data for the design of mechanical vibration plug apparatus, on-site vibration plugs, and the development of operational specifications for vibration plugs, but also provides solid engineering guidance.

关键词： Plugging and abandonment Cement plug Vibration Mechanical properties Microstructure

Direct Approach Based on the Separation of Variables for the Soliton Study of Perturbed Sine-Gordon Equation

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Chinese Physics Letters 1997年第9期14卷 671-674页

作者： YAN Jia-ren TANG yi CheN Zhen-hua Department of Physics Hunan Normal UniversityChangsha 410081 Institute of Nonequilibrium Materials South-Central University of TechnologyChangsha 410083

A new direct approach based on the separation of variables for the study of soliton perturbations is *** an example,the effects of perturbation on a soliton(kink),i.e.,both the time-dependence of soliton parameters and the first-order correction are derived for perturbed sine-Gordon *** approach is very concise and easy to understand,and it can be extended directly to deal with other nonlinear evolution equations.

关键词： equation. equations. soliton

Direct Approach for Kink Solution of Ф - 4 Equation Under Perturbation

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Chinese Physics Letters 1997年第11期14卷 845-848页

作者： TANG yi YAN Jia-ren CheN Zhen-hua Department of Physics Inner Mongolia UniversityHuhehaote 010021 Department of PhysicsHu’nan Normal UniversityChangsha 410081 Department of Physics Hu’nan Normal UniversityChangsha 410081 Institute of Nonequilibrium Materials Center-South University of TechnologyChangsha 410083

Perturbations about kink solution ofФ-4 equation are investigated by a direct approach which was recently developed in a study of soliton perturbation *** this scheme,the derivative expansion method from classical perturbation theory is employed to linearize the perturbed *** solution of the linearized equation for first-order correction is derived by the method of Laplace *** the same time,the parameters variation is obtained directly from the secularity conditions.

关键词： equation. conditions. theory.

DRILLING CHARACTERISTICS OF COMBINATIONS OF DIFFErenT HIGH PRESSURE JET NOZZLES

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Journal of Hydrodynamics 2011年第3期23卷 384-390页

作者： ZHANG Yu-ying LIU Yong-wang XU yi-ji ren Jian-hua College of Petroleum Engineering China University of Petroleum （East China） Dongying 257061 China

The high speed fluid jet for directly or indirectly breaking rock is one of the most effective ways to improve the deep penetration rate. In order to maximize the efficiency of energy use, the flow characteristics of different combinations of high pressure jet nozzles are analyzed through numerical simulations. According to the velocity vectors at the bottom and the bottom hole pressure diagram, the effects of the high pressure nozzle combinations on the flow structure and the penetration rate are analyzed. It is shown that the combination of three vertical edge nozzles is very efficient, but inefficient in cleaning the bottom hole and eroding the wall. The jet velocity is 400 m/s and the radius is 5 mm, with a center nozzle added, the problem can be solved, but the high-pressure fluid displacement would increase. The center nozzle＇s jet velocity is 200 m/s and the radius is 8 ram, the combination of two vertical edge nozzles and a center tilt nozzle or that of a vertical edge nozzle and a center tilt nozzle would provide a flow structure favorable for drilling. The angle of inclination is 10°. To take advantage of high pressure jet energy to improve the efficiency of drilling, it is important to select a suitable nozzle combination according real conditions.

关键词： Rate Of Penetration (ROP) rock breaking high pressure jet nozzle combination numerical simulation energy use

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皖南山区洞栖性蝙蝠的本底资源现状调查

安徽师范大学学报（自然科学版） 2024年第3期47卷 237-240页

作者：凌化矾任毅刘嵩姜贺孙浩吴孝兵潘涛安徽省野生动物疫源疫病监测总站安徽合肥230000 安徽师范大学生命科学学院安徽芜湖241000

2022年6—8月,基于竖琴网、雾网、抄网等工具,对安徽省皖南山区洞栖型翼手目(Chiroptera)多样性进行了调查。调查中共发现翼手目动物4科4属17种,其中,菊头蝠科(Rhinolophidae)1属8种,占比47.05%;蹄蝠科(Hipposideridae)1属2种,占比11.7... 详细信息

2022年6—8月,基于竖琴网、雾网、抄网等工具,对安徽省皖南山区洞栖型翼手目(Chiroptera)多样性进行了调查。调查中共发现翼手目动物4科4属17种,其中,菊头蝠科(Rhinolophidae)1属8种,占比47.05%;蹄蝠科(Hipposideridae)1属2种,占比11.76%;蝙蝠科(Vespertilionidae)1属6种占比35.29%;长翼蝠科(Miniopteridae)1属1种,占比5.88%。从动物区系来看,东洋型共有12种,占比70.59%,南中国型(1种)和季风型(4种)较少。结果显示皖南山区在安徽省洞栖蝙蝠物种丰富度方面,具有较高的多样性水平。此外,在调查的基础上,对皖南山区洞穴型蝙蝠的濒危等级、保护现状、区系特点进行了概述。本次调查能够为安徽省后期开展的翼手目动物资源调查与监测工作提供科学依据。

关键词：皖南山区野生动物调查翼手目(蝙蝠) 洞穴

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连续油管井下牵引器自适应控制设计及仿真

计算机仿真 2024年第8期41卷 93-98,126页

作者：郑杰白杨杰任丰伟窦益华西安石油大学机械工程学院陕西西安710065 西安特种设备检验检测院陕西西安710065 宝鸡石油机械有限责任公司陕西宝鸡721015 中油国家油气钻井装备工程技术研究中心有限公司陕西宝鸡721015 西北工业大学动力与能源学院陕西西安710072

当连续油管在水平段受到过大摩擦阻力而无法达到预定位置或出现自锁时,需要采用牵引器来增加连续油管的极限下入深度,使连续油管达到预定作业位置。针对井下牵引器控制系统的调节速度与误差抑制问题,设计了基于模糊神经网络PID控制策略... 详细信息

当连续油管在水平段受到过大摩擦阻力而无法达到预定位置或出现自锁时,需要采用牵引器来增加连续油管的极限下入深度,使连续油管达到预定作业位置。针对井下牵引器控制系统的调节速度与误差抑制问题,设计了基于模糊神经网络PID控制策略,调整了其模糊规则;最后,在阶跃响应和正弦信号下进行Simulink仿真,验证其动态性能与静态性能。通过实验分析,结果表明:在阶跃响应下的上升时间为1.8s,系统无超调,调节时间为2s;正弦响应的最大滞后时间在0.3s左右,最大幅值误差在0.05kPa,幅值误差小,快速性好,跟随性能优越。基于模糊神经网络PID控制超调量减少51.3%,调节时间减少3.6s,可以更好的控制牵引器,使连续油管更加稳定准确快速的达到预定作业位置。

关键词：连续油管井下牵引器控制系统模糊神经网络仿真分析