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Sealing analysis of cement plug in offshore abandoned wells 20th

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Sealing analysis of cement plug in offshore abandoned wells

20th Chinese Materials conference, CMC 2019

作者： Tang, Geng Yan, Hui Li, Jun Song, Xuefeng Zhang, Xin Guo, Xueli Petro China Southwest Oil & Gasfield Company Chengdu610000 China China University of Petroleum-Beijing Beijing102249 China China University of Petroleum-Beijing at Karamay Karamay834000 China CNOOC Safety Technology Service Co. Ltd. Tianjin 300450 China CNPC Engineering technology R&D Company Limited Beijing102206 China

ISBN: (纸本)9783035715668

A three-dimensional finite element model of stratum-cement ring-casing-cement plug was established for the failure analysis of the cement plug seal in the abandoned oil and gas wells. The mechanical parameters, length, bottom fluid pressure and casing swaging length of the cement plug under non-uniform ground stress conditions were analyzed. The results showed that when the bottom of the cement plug was subjected to fluid pressure, the stress at the interface between the cement plug and the casing increased, and thereby the cement plug at the bottom and the cementation of the casing failed, resulting in a the decrease in the sealing performance of the cement plug, which may be sealed under fluid corrosion. As the modulus of elasticity and the radius of the cement plug increased, the cement plug stress and the cement failure length increased. As the cement plug length increased, the cement plug stress and the cement failure length decreased, while Poissons ratio for the cem ent plug stress and the cement failure length increased. The increase of the bottom fluid pressure could increase the cement plug stress and the cementation failure length. In the abandoned well, where the casing was forged and then grinded after the casing was forged, the length of the casing milling increased, the plug stress of cement reduced. These findings can provide insightful potentials for the parameters of cement plugs when the cement plugs are closed in the offshore oil and gas wells. © 2020 Trans Tech Publications ltd, Switzerland.

关键词： Cements

Highly Elastic,Bioresorbable Polymeric Materials for Stretchable,Transient Electronic Systems

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Nano-Micro Letters 2024年第6期16卷 1-13页

作者： Jeong‑Woong Shin dong‑Je Kim Tae‑Min Jang Won Bae Han Joong Hoon Lee Gwan‑Jin Ko Seung Min Yang Kaveti rajaram Sungkeun Han Heeseok Kang Jun Hyeon Lim Chan‑Hwi Eom Amay J.Bandodkar Hanul Min Suk‑Won Hwang KU‑KIST Graduate School of Converging Science and Technology Korea University145 Anam‑roSeongbuk‑guSeoul 02841Republic of Korea SK Hynix 2091Gyeongchung‑daeroBubal‑eupIcheon‑siGyeonggi‑do 17336Republic of Korea Hanwha Systems Co. Ltd.188Pangyoyeok‑roBundang‑guSeongnam‑siGyeonggi‑do 13524Republic of Korea Department of Electrical and Computer Engineering North Carolina State UniversityRaleighNC 27606USA Center for Advanced Self‑Powered Systems of Integrated Sensors and Technologies(ASSIST) North Carolina State UniversityRaleighNC 27606USA Department of Integrative Energy Engineering Korea University145 Anam‑roSeongbuk‑guSeoul 02841Republic of Korea Biomaterials Research Center Korea Institute of Science and Technology(KIST)5 Hwarang‑ro 14‑gilSeongbuk‑guSeoul 02792Republic of Korea Semiconductor R&D Center Samsung Electronics Co.Ltd.Hwaseong‑siGyeonggi‑do 18448Republic of Korea Center for Advanced Biomolecular Recognition Biomedical Research DivisionKorea Institute of Science and Technology(KIST)Seoul 02792Republic of Korea

Substrates or encapsulants in soft and stretchable formats are key components for transient,bioresorbable electronic systems;however,elastomeric polymers with desired mechanical and biochemical properties are very limited compared to nontransient ***,we introduce a bioresorbable elastomer,poly(glycolide-co-ε-caprolactone)(PGCL),that contains excellent material properties including high elongation-at-break(<1300%),resilience and toughness,and tunable dissolution *** of PGCLs as polymer matrices,in combination with conducing polymers,yields stretchable,conductive composites for degradable interconnects,sensors,and actuators,which can reliably function under external *** of device components with wireless modules demonstrates elastic,transient electronic suture system with on-demand drug delivery for rapid recovery of postsurgical wounds in soft,time-dynamic tissues.

关键词： Biodegradable elastomer conductive polymer composites Biomedical device Transient electronics

Uncovering the Mechanism of the Lme Susceptibility for the Galvanized and Electrogalvanized dp 1180 Steels

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SSrN 2023年

作者： Zhou, Jiayi Sun, Yu Hu, Tianhan Pan, Hua Lei, Ming ding, Kai Gao, Yulai State Key Laboratory of Advanced Special Steel School of Materials Science and Engineering Shanghai University Shanghai200444 China Automobile Steel Research Institute R&D Center Baoshan Iron & Steel Co. Ltd. Shanghai201900 China State Key Laboratory of Development and Application Technology of Automotive Steels Shanghai201900 China Shanghai Engineering Research Center for Metal Parts Green Remanufacture Shanghai200444 China

dP 1180 advanced high strength steel (AHSS) used in automobiles is usually protected from corrosion by the Zn-based coating. However, liquid metal embrittlement (LME) tends to occur in Zn-coated dP 1180 steel during the resistance spot welding (rSW) process. In the present study, the LME phenomenon of the galvanized (GI) and electrogalvanized (EG) dP 1180 steel was comparatively investigated based on the LME susceptibility evaluation standard. The results showed that the observed longest crack for dP 1180 steel with GI coating was around 121.2 μm at the shoulder of the welding spot. On the contrary, the maximum length of the LME crack was as long as 792.6 μm located at the center of the welding spot for the specimen with EG coating. due to the different galvanizing processes, the microstructure could differ during the annealing, thus influencing the occurrence of LME. Furthermore, the microstructure observation results reflected that the protection of an interfacial oxide layer in GI specimen could alleviate the formation of LME to some extent. Therefore, it is deemed that the existence of the interfacial oxide layer could account for the various LME susceptibility of the GI and EG dP 1180 steels. © 2023, The Authors. All rights reserved.

关键词： Grain boundaries

Mechanism Studies of Gliadin-Glucose Glycation reaction and Products Formation by Heat Treatment with different conduction Modes

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SSrN 2024年

作者： Jiang, Qiannan Hu, Xiangfei Tu, Zongcai Wen, Pingwei Zhou, Yanru Xie, Zuohua Zhang, Siqiong Wang, Hui Hu, Yueming National Engineering Research Center of Wheat and Corn Further Processing Henan University of Technology Zhengzhou450002 China State Key Laboratory of Food Science and Resources Nanchang University Nanchang330047 China National R&D Center of Freshwater Fish Processing Jiangxi Normal University Nanchang330022 China International Institute of Food Innovation Co. Ltd. Nanchang University Nanchang330052 China Jiangxi Deshang Pharmaceutical Co. Ltd. Yichun331208 China Chongqing Research Institute Nanchang University Chongqing402660 China

Heat treatments induce protein-reducing sugar glycation reactions easily, leading to protein structural transformations and advanced glycation end products generation. However, different heat conduction modes have different effects on the gliadin-glucose system, resulting in different impacts on nutrition and safety of the products. In this study, effects of four heat conduction modes (air, contact, vapour and liquid-conduction) on the spatial conformation and glycation products of gliadin-glucose system were evaluated. The experimental results showed that different conduction modes resulted in different amounts of Amadori products, methylglyoxal, acrylamide and other glycation products in this system, while air conduction has a low product content. The above phenomena are due to the fact that different conduction modes have different water content during the reaction process and exhibit different effects on glycation promotion. In particular, gliadin exposed fewer hydrophobic and fluorescent groups in air-conduction, resulting in the fewer glycation sites, lower glycation degree and less products. © 2024, The Authors. All rights reserved.

关键词： Glycosylation

Hard Sample Matters a Lot in Zero-Shot Quantization

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arXiv

arXiv 2023年

作者： Li, Huantong Wu, Xiangmiao Lv, Fanbing Liao, daihai Li, Thomas H. Zhang, Yonggang Han, Bo Tan, Mingkui South China University of Technology China Changsha Hisense Intelligent System Research Institute Co. Ltd China Hong Kong Baptist University Hong Kong Key Laboratory of Big Data and Intelligent Robot Ministry of Education China PengCheng Laboratory China Information Technology R&D Innovation Center of Peking University China School of Electronic and Computer Engineering Peking University Shenzhen Graduate School Shenzhen China

Zero-shot quantization (ZSQ) is promising for compressing and accelerating deep neural networks when the data for training full-precision models are inaccessible. In ZSQ, network quantization is performed using synthetic samples, thus, the performance of quantized models depends heavily on the quality of synthetic samples. Nonetheless, we find that the synthetic samples constructed in existing ZSQ methods can be easily fitted by models. Accordingly, quantized models obtained by these methods suffer from significant performance degradation on hard samples. To address this issue, we propose HArd sample Synthesizing and Training (HAST). Specifically, HAST pays more attention to hard samples when synthesizing samples and makes synthetic samples hard to fit when training quantized models. HAST aligns features extracted by full-precision and quantized models to ensure the similarity between features extracted by these two models. Extensive experiments show that HAST significantly outperforms existing ZSQ methods, achieving performance comparable to models that are quantized with real data. copyright © 2023, The Authors. All rights reserved.

关键词： deep neural networks

Simultaneous Separation and determination of Phenolic Isomers and Analogues in Flue Gas Aerosols

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SSrN 2024年

作者： Wang, dongsheng Zhang, di Shi, Lin Jiang, Wei Peng, Qiyuan Liu, Zhihua Si, Xiaoxi Yunnan Provincial Key Laboratory of Soil Carbon Sequestration and Pollution Control Faculty of Environmental Science and Engineering Kunming University of Science and Technology Kunming650500 China Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection College of Resources and Environment Linyi University Linyi276005 China Yunnan Key Laboratory of Tobacco Chemistry R&D Center of China Tobacco Yunnan Industry Co. Ltd. Kunming650231 China

To achieve the accurate quantification of phenolic substances in a complex matrix, a chiral column separation combined with gas chromatography‒mass spectrometry (GC‒MS) method for the simultaneous separation and detection of 43 phenolic substances was established and successfully applied to the determination of cigarette smoke aerosol particles. Smoking modes were selected according to the smoking behavior of different types of tobacco products. The smoke aerosol particles of 5 tobacco sticks were collected with a Cambridge filter and extracted by ethanol. CP-Cyclodextrin-β-2,3,6-M-19 columns were selected to separate them, and selected ion monitoring mode was selected for determination. The results showed that 43 phenolic substances achieved high separation without derivatization pretreatment and direct injection after ethanol extraction. The separation degrees of the chromatographic peaks were all greater than 1.268, and the chromatographic peaks were sharp and symmetrical. The limits of quantitation were 0.002-0.047 μg/mL, the recoveries were 75.3%-117.8%, and the relative standard deviations (rSd) were 0.7-9.2%. In addition, the matrix effect factor of this method ranges from 0.847 to 1.153, indicating high accuracy in the case of a high concentration of matrix interference. The analysis of 36 kinds of flue-cured tobacco samples and 13 kinds of cigarette matrices of nonburning cigarettes proved that the method was simple, accurate, reliable and sensitive and was suitable for the simultaneous separation and detection of monophenols and phenylcatechol compounds of different substitution types in complex matrices. © 2024, The Authors. All rights reserved.

关键词： Tobacco

A dendrite-Blocking Polyimide-Meta-Aramid Separator with Ultrahigh Strength and Thermostability for High-Security Lithium-Ion Battery

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SSrN 2023年

作者： Qi, Shengli Li, Xiaogang Liu, Kefan dong, Nanxi Liu, Bingxue Tian, Guofeng Wu, dezhen State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing100029 China China Automotive Battery Research Institute Co. Ltd. No.11 Xingke Dong Street Yanqi Economic Development Zone Huairou District Beijing101407 China ENFI R&D Institute China ENFI Engineering Corporation No. 12 Fuxing Avenue Haidian District Beijing100038 China

commercial polyolefin-based separators broadly applied in lithium-ion batteries (LIBs) seriously affect the safety and development of LIBs due to the poor thermostability and electrolyte wettabilitycaused by its low melting point and non-polar structure. In this work, a simple self-adsorption crosslinking technology is invented to fabricate polyimide-meta-aramid (PI-MA) separators with superior thermostability, wettability and safety. This technology utilizes the hydrogen bond adsorption and MA self-adhesive effect to realize the close encapsulation of MA on the surface of PI nanofiber and form a compact crosslinking structure. Specifically, the PI-MA separator has no significant deformation at 300 °C, while PP has completely melted and contracted at 200 °C. The PI-MA exhibits an electrolyte contact angle as low as 6.1 ° and the faster electrolyte diffusion rate in both horizontal and vertical directions. Moreover, in the long-term stripping/plating characterization, the lithium symmetric cell with PI-MA exhibits the stable cycle performance at a current density of 2 mA cm-2 for 1000 h. Using LiNi0.8co0.1Mn0.1O2 (NCM811) as cathode, the cell with PI-MA has a capacity retention rate of 82.1% in the 300-cycle test at 1 C, much higher than 58.3% of PP separator. compared with the cell assembled with PP separator exploding at 56 min, the cell with PI-MA discharged stably to the cut-off voltage within 160 min at 120 °C. © 2023, The Authors. All rights reserved.

关键词： Lithium-ion batteries

Enhanced Visual Pipeline defect detection Using Partial convolution Image restoration

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Enhanced Visual Pipeline Defect Detection Using Partial Conv...

2021 International conference on Signal Processing and Machine Learning (coNF-SPML)

作者： Mingcun Liu Ce Li rui Yan Yunzhi Xu Jingyi Qiao Feng Yang Computer Science and Technology China University of Mining & Technology Beijing Science and Technology R&D Center Beijing Urban Drainage Group Co. LTD School of Mechanical Electronic & Information Engineering China University of Mining & Technology Beijing

ISBN: (纸本)9781665417358

In urban construction,the defect detection and repair work of drainage pipe-lines are very important,and visual defect detection on pipeline inner surface has become a hot research issue in the application of computer vision and pipeline ***,it is still difficult to detect the defects automatically because it is limited by low-quality video and different models of *** present,most pipeline detection methods are implemented by pipeline robots equipped with high-definition cameras and manual recognition to find defects frame by *** cope with these issues,this paper proposes a method of visual pipeline defect detection enhanced by image *** which,the image restoration using partial convolution is firstly proposed to impair the image that is locally occluded by the haulage rope,then the fast detection using enhanced image data is proposed for pipeline *** analyzing the influence of the restoration on the defect detection,the experiment results show that our method has produced significantly improved detection performance by the partial image restoration and it is an efficient method for the application of pipeline robot.

关键词： Pipeline robot defect detection Image restoration Partial convolution

Study on the Tensile and Bonding Properties between Cement-Based Grout Material and High-Strength Bolt

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SSrN 2023年

作者： Liu, Peng Zhi, Weiting Mao, Jianfeng Liu, Lei Chen, Ying Yu, Zhiwu He, Sasa Zhang, Ning Hu, Cheng School of Civil Engineering Central South University 22 Shaoshan Road Changsha410075 China National Engineering Research Center for High Speed Railway Construction Changsha410075 China School of Civil Engineering Central South University of Forestry and Technology 498 Shaoshan Road Changsha410004 China School of Physical and Technology YiLi Normal University 448 Jiefang West Road Yining835000 China Central South University China Hunan Aircraft Landing System Technology R&D Co. Ltd. 29 Qingzhuhu Road Changsha410153 China

This study investigated the tensile and bonding properties between cement-based grouting materials (CBGM) and high-strength bolts. The associated failure mechanism, load-slip curve, ultimate pull-out load and bond stress were also studied. The effects of anchorage length and square steel tube restraint on the bonding properties were explored on the basis of 24 specimens central pull-out testing, and a bond stress-slip constitutive relationship model between high-strength bolts and CBGM was proposed. The results indicate that with the increase of the anchorage length of high-strength bolts, the failure mode of specimens can be divided into three types: the fracture failure of high-strength bolt was occurred with the anchorage lengths ranging from 18 d to 31 d;when the anchorage length was less than 15 d, the specimen occurred splitting failure with the constraint of square steel tube, and the high-strength bolt occurred pull-out failure without the constraint of square steel tube. When the high-strength bolt occurred the tensile failure, the ultimate pull-out load remains a constant and the bond stress decreases as the increase of the anchorage length of high-strength bolt. due to the lateral constrained effect of the square steel tube, the CBGM embodies a three-dimensional stress state, which can delay the generation and development of the internal cracks, and enhance the bond strength. A calculation formula was proposed to determine the bond strength between high-strength bolt and CBGM, and a constitutive model of the bond stress-slip constitutive relationship was also modeled. © 2023, The Authors. All rights reserved.

关键词： Mortar