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Stress corrosion cracking behavior of buried oil and gas pipeline steel under the coexistence of magnetic field and sulfate-reducing bacteria

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Petroleum Science 2024年第2期21卷 1320-1332页

作者： Jian-yu He Fei xie Dan Wang guang-Xin Liu Ming Wu yue Qin College of Petroleum Engineering Liaoning Petrochemical UniversityFushun113001LiaoningChina Key Laboratory of Oil and Gas Storage and Transportation Technology in Liaoning Province Fushun113001LiaoningChina State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China PipeChina West East Gas Pipeline Company Shanghai200120China

Magnetic field and microorganisms are important factors influencing the stress corrosion cracking(SCC)of buried oil and gas pipelines. Once SCC occurs in buried pipelines, it will cause serious hazards to the soil environment. The SCC behavior of X80 pipeline steel under the magnetic field and sulfate-reducing bacteria(SRB) environment was investigated by immersion tests, electrochemical tests, and slow strain rate tensile(SSRT) tests. The results showed that the corrosion and SCC sensitivity of X80 steel decreased with increasing the magnetic field strength in the sterile environment. The SCC sensitivity was higher in the biotic environment inoculated with SRB, but it also decreased with increasing magnetic field strength, which was due to the magnetic field reduces microbial activity and promotes the formation of dense film layer. This work provided theoretical guidance on the prevention of SCC in pipeline steel under magnetic field and SRB coexistence.

关键词： Magnetic field Sulfate-reducing bacteria Film layer Stress corrosion cracking Oil and gas pipelines

A new neutron detector based on ceramic THGEM and boron-coated meshes

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Radiation Detection Technology and Methods 2018年第1期2卷 169-177页

作者： Geng-lan Li yu-guang xie Hang Zhao Wen-Qi Yan yu-Lan Li Zhi-yuan Peng Tao Hu Jun-guang Lv Li Zhou Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Particle Detection and Electronics Beijing 100049China University of Chinese Academy of Sciences Beijing 100049China guangxi University Nanning 530004GuangxiChina

Introduction Boron-coated micro-pattern gaseous detectors,such as gaseous electron multiplier(GEM),are widely studied as the neutron *** existing solution to improve the neutron detection efficiency(NDE)is to coat the boron on the surfaces of the cascade GEM *** the GEM films themselves will be affected by the complicated coating process and the boron layers,and the 10B material will be wasted once the GEM films are *** the neutron conversion and the electron multiplication regions are not separated,the final gains of different layer ionized electrons are very difficult to control and keep *** and methods A new neutron detector based on the ceramic thick GEM(THGEM)was *** boron-coated cathode and multilayer meshes were used as the neutron conversion region and separated from the electron multiplication region consisting of only one THGEM *** sawtooth surface treatment and the double-sided readout method were applied to improve neutron conversion efficiency(NCE).The neutron conversion and the electron collection efficiencies were simulated and studied based on the new *** prototype detector was test by using a ^(252)Cf neutron *** The simulation results show that the cascade boron-coated meshes have good neutron conversion and electron collection efficiencies,and the double-sided readout and sawtooth structure can greatly increase the *** neutron test results show that the detection efficiency of the double-sided readout is 1.6 times higher than that of the common single-sided *** indicate that the new detector has high neutron conversion and detection efficiencies and is promising for practical applications.

关键词： THGEM Neutron detector Boron-coated Mesh Conversion efficiency

Performance study of trial M-THGEM

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Radiation Detection Technology and Methods 2020年第1期4卷 78-82页

作者： Shao-Qing Deng Wen-Qi Yan Dao-Jin Hong Bo-Xiang yu Gao-Long Zhang yu-guang xie School of Physics and Nuclear Energy Engineering Beihang UniversityBeijing 100191China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China University of Science and Technology of China Hefei 230026China State Key Laboratory of Particle Detection and Electronics Beijing 100049China University of Chinese Academy of Sciences Beijing 100049China Beijing Advanced Innovation Center for Big Data-Based Precision Medicine Beihang UniversityBeijing 100083China

Background M-THGEM is a new type of electron multiplier,which is developed with a high gain,good stability and uniformity based on *** the successful application of small area M-THGEM,the large-area M-THGEM is proposed based on large-volume gas *** The production of large-area M-THGEM is difficult compared with the small one with more holes and more stable *** meet the requirements of large-area gas detectors,the performances of the large-area M-THGEM need to be measured and researched,which will provide a guidance on the process and design of the *** The M-THGEM membrane was loaded into a chamber to complete the test under the conditions of 55Fe/X-ray source(5.9 keV)and working gas Ar∶iC4H10=97∶*** performance of gain,energy resolution,uniformity and long-term stability can be *** Based on the small area M-THGEM,the research and design of large-area M-THGEM with 200×200 mm^(2)were *** basic performances were *** results show that the gain with the working gas of Ar∶iC_(4)H_(10)=97∶3 can reach to 6×10^(3),and the energy resolution of the^(55)Fe/X-ray source(5.9 keV)reaches 29.4%with a good gain uniformity and *** At present,the production and measurement of the large-area M-THGEM has been *** M-THGEM of 200×200 mm^(2)shows a good performance,which will provide many references for the future design.

关键词： M-THGEM Gain Energy resolution Stability

Influence of Vanes and Blades on Ingress in Axial Rim Seal for Turbine Stages

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Journal of Thermal Science 2024年第3期33卷 833-846页

作者： REN Ran DU Qiang LIU guang ZENG Yanlian xie Lei Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China National Key Laboratory of Science and Technology on Advanced Light-duty Gas-turbine Beijing100190China School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing100190China

Hot gas ingestion refers to the phenomenon of mainstream hot gas flowing into the space cavity of a turbine *** studies have found that mainstream annulus pressure distribution plays an important role in hot gas ingestion,but due to its complexity,the mechanism of the interaction between mainstream flow and hot gas ingestion remains *** paper adopts the URANS method,and three sealing flow rates are considered,named C_(w)=0,C_(w)=500,and C_(w)=*** time-averaged annulus pressure distribution shows that an increase in the sealing flow decreases the pressure value,and the effects of the sealing flow on the pressure distribution of the leading edge of the blade are much more influential than that of the trailing edge of the *** unsteady pressure time-space distribution in the annulus indicates that a time-space tilted distribution of pressure at the rim exits when the sealing flow *** phenomenon is mainly due to the strong feedback mechanism of the sealing flow to the annulus pressure field.A comparison of the pressure and mean radial velocity distribution of the mainstream shows that the ingestion mainly occurs on the blade side,where the pressure is lower than on the vane *** flow characteristics at the wheel rim are analyzed with a sealing flow rate C_(w)=5000,and under these conditions,both pressure-induced ingestion and ingestion caused by a passage vortex can be *** three-dimensional and inertial effects of the mainstream at the wheel rim lead to the generation of separation vortices on the blade side,and the presence of separation vortices leads to ingestion along the blade *** the same time,pressure on the blade side will cause the fluid to have a radial inward flow tendency,which will promote the formation of separation vortices,leading to more serious ingestion in the high-pressure region on the blade *** blade pressure field can be more significant than the vane trailing pressure field in the rim sea

关键词： separation vortex unsteady rim seal the effect of blade on ingestion

Literature overview of basic characteristics and flotation laws of flocs

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 943-958页

作者： Wanzhong Yin yu xie Zhanglei Zhu School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China College of Chemistry and Chemical Engineering Xi’an University of Science and TechnologyXi’an 710054China

Flocculation flotation is the most efficient method for recovering fine-grained minerals,and its essence lies in flotation and recovery of *** physical characteristics of flocs are mainly determined by their apparent particle size and structure(density and morphology).Substantial researches have been conducted regarding the effect of floc characteristics on particle settling and water ***,the influence of floc characteristics on flotation has not been widely *** on the floc formation and flocculation flotation,this study reviews the fundamental physical characteristics of flocs from the perspectives of floc particle size and structure,summarizing the interaction between floc particle size and ***,it thoroughly discusses the effect of floc particle size and structure on floc floatability,further revealing the influence of floc characteristics on bubble collision and adhesion and elucidating the mechanisms of interaction between flocs and ***,it is observed that floc particle size is not the only factor influencing flocculation *** the appropriate apparent particle size range,flocs with a compact structure exhibit higher efficiency in bubble collision and adhesion during flotation,thereby resulting in enhanced flotation *** study aims to provide a reference for flocculation flotation,targeting the development of more efficient and refined flocculation flotation processes in the future.

关键词： flocs basic characteristics particle size and structure flotation laws bubbles

Development and study of an imaging detector based on high-position resolution THGEM

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Radiation Detection Technology and Methods 2017年第1期1卷 40-47页

作者： Hang Zhao yu-guang xie Wen-Qi Yan Tao Hu Jun-guang Lv Li Zhou Xiao-Shan Jiang Zhe Ning Fei Li Si Ma Feng Shi Zhi-Gang Wang yu-Lan Li Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Particle Detection and Electronics Beijing 100049China University of Chinese Academy of Sciences Beijing 100049China guangxi University NanningGuangxi 530004China

Introduction THickGaseous Electron Multiplier(THGEM)has many advantages while the moderate position resolution is regarded as the main inferiority comparing with the traditional GEM,so this limits the applications of THGEM,such as X-ray imaging and charge particle *** and methods By improving the production techniques,THGEMs with smaller pitch and hole diameter can be made,i.e.,0.4 and 0.15 mm by mechanical drilling,and 0.3 and 0.1 mm by laser etching,*** on the new THGEMs,a two-dimensional imaging detector with 50×50mm sensitive area was developed for 0.1∼50 MeVlow-energy electrons detection and reaching better than 100μm position resolution(sigma).At the same time,a set of front-end electronics was developed based on homemade ASIC chips,i.e.,Charge Amplifier and Shaping Amplifier for GEM(CASAGEM),and applied successfully to the *** The X-ray and beam tests results indicate that both detector and Front End Electronics(FEE)worked well,and the position resolution achieved 74.9μm by using the charge center-of-gravity *** indicates that the high-position resolution THGEM is promising for imaging and tracking application.

关键词： THGEM Imaging detector Position resolution ASIC Low energy electron

Full waveform inversion based on hybrid gradient

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Petroleum Science 2024年第3期21卷 1660-1670页

作者： Chuang xie Zhi-Liang Qin Jian-Hua Wang Peng Song Heng-guang Shen Sheng-Qi yu Ben-Jun Ma Xue-Qin Liu Qingdao Innovation and Development Base Harbin Engineering UniversityQingdao266000ShandongChina Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao266000ShandongChina CNOOC Research Institute Co. Ltd.Beijing100028China College of Marine Geoscience Ocean University of ChinaQingdao266100ShandongChina Weihai Sunfull Geophysical Exploration Equipment Co. Ltd.Weihai264209ShandongChina

The low-wavenumber components in the gradient of full waveform inversion(FWI)play a vital role in the stability of the ***,when FWI is implemented in some high frequencies and current models are not far away from the real velocity model,an excessive number of low-wavenumber components in the gradient will also reduce the convergence rate and inversion *** solve this problem,this paper firstly derives a formula of scattering angle weighted gradient in FWI,then proposes a hybrid *** hybrid gradient combines the conventional gradient of FWI with the scattering angle weighted gradient in each inversion frequency band based on an empirical formula derived *** weighted hybrid mode,we can retain some low-wavenumber components in the initial lowfrequency inversion to ensure the stability of the inversion,and use more high-wavenumber components in the high-frequency inversion to improve the convergence *** results of synthetic data experiment demonstrate that compared to the conventional FWI,the FWI based on the proposed hybrid gradient can effectively reduce the low-wavenumber components in the gradient under the premise of ensuring inversion *** also greatly enhances the convergence rate and inversion accuracy,especially in the deep part of the *** the field marine seismic data experiment also illustrates that the FWI based on hybrid gradient(HGFWI)has good stability and adaptability.

关键词： Full waveform inversion Hybrid gradient Scattering angle weighted Low-wavenumber component

Method for Detecting Industrial Defects in Intelligent Manufacturing Using Deep Learning

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Computers, Materials & Continua 2024年第1期78卷 1329-1343页

作者： Bowen yu Chunli xie College of Mechanical and Electrical Engineering Northeast Forestry UniversityHarbin150040China

With the advent of Industry 4.0,marked by a surge in intelligent manufacturing,advanced sensors embedded in smart factories now enable extensive data collection on equipment *** analysis of such data is pivotal for ensuring production safety,a critical factor in monitoring the health status of manufacturing *** defect detection techniques,typically limited to specific scenarios,often require manual feature extraction,leading to inefficiencies and limited versatility in the overall *** research presents an intelligent defect detection methodology that leverages deep learning techniques to automate feature extraction and defect localization *** proposed approach encompasses a suite of components:the high-level feature learning block(HLFLB),the multi-scale feature learning block(MSFLB),and a dynamic adaptive fusion block(DAFB),working in tandem to extract meticulously and synergistically aggregate defect-related characteristics across various scales and hierarchical *** have conducted validation of the proposed method using datasets derived from gearbox and bearing *** empirical outcomes underscore the superior defect detection capability of our *** demonstrates consistently high performance across diverse datasets and possesses the accuracy required to categorize defects,taking into account their specific locations and the extent of damage,proving the method’s effectiveness and reliability in identifying defects in industrial components.

关键词： Industrial defect detection deep learning intelligent manufacturing

A scintillator detector for beam tuning of low-energy single electron accelerator

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Radiation Detection Technology and Methods 2017年第1期1卷 29-39页

作者： yu-lan Li yun-ting Gu yu-guang xie Jun-hui yue Jun-guang Lv Shun-li Niu Shi-lun Pei Feng Shi Ling-da yu Hang Zhao Wen-qi Yan Pin Lv Zhi-yuan Peng Geng-lan Li guangxi University Nanning 530004GuangxiChina Institute of High Energy Physics Beijing 100049China State Key Laboratory of Particle Detection and Electronics Beijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Purpose Nine scintillator detectors were developed for beam tuning of low-energy single electron accelerator instead of the picoammeter and Faraday cup,both of which will be insensitive to the weak-current beam lower than *** The detectors are based on plastic scintillator and photomultiplier tube(PMT)and the beam is 100 Hz pulsed electrons in the energy range of 0.1 to *** beam flux was tuned from about 107 to quasi-single electron for each bunch according to the measurement results of these detectors installed along the beam pipe and after *** order to determine the number of electrons in a bunch,the gains of each PMT were finely calibrated,and the energy response of each detector was calibrated with 207Bi radioactive ***,the deposited energy in the plastic scintillator,the electron detection efficiency and light collection efficiency,as a function of electron incident energy,were also simulated in detail by *** Nine detectors worked well at a gain of 0.6×10^(6) after installation in the beam pipe,and the number of electrons in a bunch could be measured at each detector *** single electron peak was seen when the beam reached the final *** The commissioning result shows that the beam was tuned to quasi-single electron level successfully and the scintillator detector is an effective method to measure the weak-current beam lower than picoampere.

关键词： Beam tuning Single electron beam PMT Plastic scintillator Slit