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Research on the solid particle erosion wear of pipe steel for hydraulic fracturing based on experiments and numerical simulations

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Petroleum Science 2024年第4期21卷 2779-2792页

作者： Si-Qi Yang Jian-Chun Fan Ming-Tao liu De-Ning li Jun-liang li li-hong han Jian-Jun Wang Shang-Yu Yang Si-Wei Dai Lai-Bin Zhang State Key Laboratory of Oil and Gas Equipment CNPC Tubular Goods Research Institute Key Laboratory of Oil and Gas Safety and Emergency Technology China University of Petroleum Oil Production Technology Research Institute of liaohe Oilfield Company Tianjin Gas Storage Branch PetroChina Dagang Oilfield Company Petroleum Production Engineering Research Institute Daqing Oilfield Company

Erosion wear is a common failure mode in the oil and gas industry. In the hydraulic fracturing, the fracturing pipes are not only in high-pressure working environment, but also suffer from the impact of the high-speed solid particles in the fracturing fluid. Beneath such complex conditions, the vulnerable components of the pipe system are prone to perforation or even burst accidents, which has become one of the most serious risks at the fracturing site. Unfortunately, it is not yet fully understood the erosion mechanism of pipe steel for hydraulic fracturing. Therefore, this article provides a detailed analysis of the erosion behavior of fracturing pipes under complex working conditions based on experiments and numerical simulations. Firstly, we conducted erosion experiments on AISI 4135 steel for fracturing pipes to investigate the erosion characteristics of the material. The effects of impact angle, flow velocity and applied stress on erosion wear were comprehensively considered. Then a particle impact dynamic model of erosion wear was developed based on the experimental parameters, and the evolution process of particle erosion under different impact angles, impact velocities and applied stress was analyzed. By combining the erosion characteristics, the micro-structure of the eroded area, and the micro-mechanics of erosion damage, the erosion mechanism of pipe steel under fracturing conditions was studied in detail for the first time. Under high-pressure operating conditions, it was demonstrated through experiments and numerical simulations that the size of the micro-defects in the eroded area increased as the applied stress increased, resulting in more severe erosion wear of fracturing pipes.

关键词： Erosion wear Applied stress Particle impact dynamics Erosion mechanism

Effect of plastic deformation on diffusion-rolling bonding of steel sandwich plates

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Journal of University of Science and Technology Beijing 2006年第6期13卷 532-537页

作者： hong li Jingtao han Materials Science and Engineering School University of Science and Technology Beijing Beijing 10083 China

Diffusion bonding is one of the most important techniques for composite materials, while bonding temperature, holding time,and rolling reduction are the key parameters that affect the bonding strength of sandwich plates. To study the effect of plastic deformation on the bonding strength, laboratory experiments were carried on a Gleeble Thermal Simulator to imitate the diffusion-rolling bonding under different reductions for steel sandwich plates. The bonding strength and interlayer film thickness were measured, and the element diffusion was analyzed using line scanning. The relationship between the bonding strength and “diffused interlayer” thickness was investigated. It has been found that the bonding strength increases with reduction, whereas the interlayer film thickness decreases gradually as the reduction increases. The diffusion under plastic deformation is obviously enhanced in comparison with that of nil reduction. The mechanism of plastic deformation effect on the diffusion bonding and related models have been discussed.

关键词： steel sandwich plate diffusion-bonding plastic deformation bonding strength interlayer film thickness diffusion mechanism models

Predication of Plastic Flow Characteristics in Ferrite/Pearlite Steel Using a Fern Unit Cell Method

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上海交通大学学报 2004年第Z2期38卷 61-66页

作者： hong li Jingtao han Jing liu Lv Zhang School of Material Sci. & Eng. Univ. Of Sci. &Tech. Beijing Beijing100083 China School of Material Sci. & Eng. Univ. Of Sci. &Tech. Beijing Beijing100083 China School of Material Sci. & Eng. Univ. Of Sci. &Tech. Beijing Beijing100083 China School of Material Sci. & Eng. Univ. Of Sci. &Tech. Beijing Beijing100083 China

The flow stress of ferrite/pearlite steel under uni-axial tension was simulated with finite element method (FEM) by applying commercial software MARC/MENTAT. Flow stress curves of ferrite/pearlite steels were calculated based on unit cell model. The effects of volume fraction, distribution and the aspect ratio of pearlite on tensile properties have been investigated.

关键词： ferrite/pearlite steel unit cell flow curve finite element method simulation

Plastid genome evolution of a monophyletic group in the subtribe Lauriineae(Laureae,Lauraceae)

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Plant Diversity 2022年第4期44卷 377-388页

作者： Chao liu Huan-Huan Chen li-Zhou Tang Phyo Kay Khine li-hong han Yu Song Yun-hong Tan College of Biological Resource and Food Engineering Yunnan Engineering Research Center of Fruit WineQujing Normal UniversityQujingYunnan655011China Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Ministry of Education) Guangxi Key Laboratory of Landscape Resources Conservation and Sustainable Utilization in Lijiang River BasinGuangxi Normal UniversityGuilinGuangxi541004China Center for Integrative Conservation Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan666303China Southeast Asia Biodiversity Research Institute Chinese Academy of SciencesYezinNay Pyi Taw05282Myanmar

litsea,a non-monophyletic group of the tribe Laureae(Lauraceae),plays important roles in the tropical and subtropical forests of Asia,Australia,Central and North America,and the islands of the ***,intergeneric relationships between litsea and Laurus,lindera,Parasassafras and Sinosassafras of the tribe Laureae remain *** this study,we present phylogenetic analyses of seven newly sequenced litsea plastomes,together with 47 Laureae plastomes obtained from public databases,representing six genera of the *** results highlight two highly supported monophyletic groups of litsea *** is composed of 16 litsea taxa and two lindera *** 18 plastomes of these taxa were further compared for their gene structure,codon usage,contraction and expansion of inverted repeats,sequence repeats,divergence hotspots,and gene *** complete plastome size of newly sequenced taxa varied between 152,377 bp(litsea auriculata)and 154,117 bp(litsea pierrei).Seven of the 16 litsea plastomes have a pair of insertions in the IRa(trnL-trnH)and IRb(ycf2)*** 18 plastomes of litsea and lindera taxa exhibit similar gene features,codon usage,oligonucleotide repeats,and inverted repeat *** codons with the highest frequency among these taxa favored A/T endings and each of these plastomes had nine divergence hotspots,which are located in the same *** also identified six protein coding genes(accD,ndhJ,rbcL,rpoC2,ycf1 and ycf2)under positive selection in litsea;these genes may play important roles in adaptation of litsea species to various environments.

关键词： litsea Phylogenetic analysis Divergent hotspots Gene evolution

Optimizing near-carbon-free nuclear energy systems:advances in reactor operation digital twin through hybrid machine learning algorithms for parameter identification and state estimation

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Nuclear Science and Techniques 2024年第8期35卷 177-203页

作者： li‑Zhan hong He‑lin Gong hong‑Jun Ji Jia‑liang Lu han li Qing li Paris Elite Institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610041China

Accurate and efficient online parameter identification and state estimation are crucial for leveraging digital twin simulations to optimize the operation of near-carbon-free nuclear energy *** previous studies,we developed a reactor operation digital twin(RODT).However,non-differentiabilities and discontinuities arise when employing machine learning-based surrogate forward models,challenging traditional gradient-based inverse methods and their *** study investigated deterministic and metaheuristic algorithms and developed hybrid algorithms to address these *** efficient modular RODT software framework that incorporates these methods into its post-evaluation module is presented for comprehensive *** methods were rigorously assessed based on convergence profiles,stability with respect to noise,and computational *** numerical results show that the hybrid KNNLHS algorithm excels in real-time online applications,balancing accuracy and efficiency with a prediction error rate of only 1%and processing times of less than 0.1 ***,algorithms such as FSA,DE,and ADE,although slightly slower(approximately 1 s),demonstrated higher accuracy with a 0.3%relative L_2 error,which advances RODT methodologies to harness machine learning and system modeling for improved reactor monitoring,systematic diagnosis of off-normal events,and lifetime management *** developed modular software and novel optimization methods presented offer pathways to realize the full potential of RODT for transforming energy engineering practices.

关键词： Parameter identification State estimation Reactor operation digital twin Reduced order model Inverse problem

Mixed State and High Effective Utilization of Pilbara Blending Iron Ore Powder

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Journal of Iron and Steel Research International 2011年第9期18卷 1-5页

作者： CAO Yong-guo WU Sheng-li han hong-liang WANG hong-wei XUE Fang liU Xiao-qin School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

Pilbara blending iron ore powder （PB powder） is blending ores with good and poor quality iron ores, so how to use PB power effectively is a problem. The self-characteristics of PB powder and its single-components were studied respectively such as the macroscopic properties, microscopic properties, and high-temperature properties the behavior and effect in the sintering were mastered. Then based on the new ore-proportioning idea of iron ores sintering characteristics complementary, the principles on the effective use of PB powder were discussed, and was fur ther validated through the sintering pot test and industrial production. The results show that PB powder is composed of three kinds of iron ore, and the sintering characteristics of different iron ores are obviously discrepant. With the ore-proportioning optimization based on the iron ores sintering characteristics complementary, the proportion of PB iron ore powder can be increased to more than 45 %.

关键词： Pilbara blending ore sintering mixed state high effective utilization

人际信任和社交焦虑在欺凌受害与孤独感之间的多重中介作用

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中国健康教育 2024年第7期40卷 662-665,670页

作者：权方英丁文博归梦琼赵颖慧李宏翰广西师范大学教育学部心理学系广西桂林541004 广西高校认知神经科学与应用心理重点实验室广西桂林541004 广西高校人文社会科学重点研究基地广西民族教育发展研究中心广西桂林541004 桂林市田家炳中学广西桂林541004

目的考察人际信任和社交焦虑在欺凌受害与孤独感之间的中介作用。方法采用特拉华欺凌受害量表、加州大学洛杉矶分校孤独量表、人际信任量表、儿童社交焦虑量表对460名中学生进行调查。结果欺凌受害与孤独感显著相关(β=0.23,P<0.001)。... 详细信息

目的考察人际信任和社交焦虑在欺凌受害与孤独感之间的中介作用。方法采用特拉华欺凌受害量表、加州大学洛杉矶分校孤独量表、人际信任量表、儿童社交焦虑量表对460名中学生进行调查。结果欺凌受害与孤独感显著相关(β=0.23,Pli=0.93。中介效应检验结果显示欺凌受害与孤独感之间的中介路径显著:欺凌受害→人际信任→社交焦虑→孤独感(中介效应值0.03),95%的置信区间均不包含0。结论中学生欺凌受害不仅会直接预测孤独感,还会通过人际信任和社交焦虑间接预测孤独感。这些结果为预防和干预中学生的孤独感提供了实践启示。

关键词：欺凌受害孤独感人际信任社交焦虑中介作用

Anatomical retroperitoneoscopic retroperitoneal lymph node dissection for clinical stage I nonseminomatous germ cell tumors： initial operative experience

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Asian Journal of Andrology 2014年第1期16卷 136-139页

作者： Kai Yao Zai-Shang li Fang-Jian Zhou Zi-Ke Qin Zhuo-Wei liu Yong-hong li Hui han Department of Urology Cancer Center Sun Yat-Sen University State Key Laboratory of Oncology in South China Collaborative Innovation Center of Cancer Medicine Guangzhou China.

To introduce the technique of anatomical retroperitoneoscopic retroperitoneal lymph node dissection （ARRPLND） was performed in 12 consecutive patients with a clinical stage I nonseminomatous germ-cell tumor （NSGCT） between February 2008 and October 2010. All procedures were performed using a modified template nerve-sparing approach. The retroperitoneal space was adequately expanded using double gasbags. After the retroperitoneal fat was cleared, two relatively bloodless planes were entered consecutively to expose the lymph node and permit dissection. Dissection proceeded first in the plane between the anterior renal fascia and posterior peritoneum, and secondly in the avascular plane between the posterior renal fascia and transversalis fascia. The proximal spermatic vein was clipped at the initial stage. En bloc resection of the lymph tissue and fat between the anterior renal fascia and posterior renal fascia were performed. Three patients （25%） had pathologic stage IIA disease and received adjuvant chemotherapy. No recurrence was observed during follow-up ranging from 26 to 58months. The median operative time was 205min （range： 165-430min） and median estimated blood loss was 320ml （range： 100-1200ml）. There were two intraoperative complications （Clavien grade II） and one open conversion due to perforation of the peritoneum. Postoperative complications （Clavien I） developed in three patients. Normal antegrade ejaculation recovered by 1 month following the operation. Our preliminary results indicate that ARRPLND is technically feasible and associated with satisfactory clinical outcomes for clinical stage I NSGCT. Further studies are necessary to evaluate this technique.

关键词： nonseminomatous retroperitoneoscopic retroperitoneal lymph node testicular cancer

Enhancing flotation recovery of residual carbon from gasification waste by mixing hydrophobic powder with diesel as collector

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Particuology 2024年第6期89卷 211-217页

作者： Rui han Ningning Zhang Anning Zhou Zhen li Jinzhou Qu hong Wang College of Chemistry and Chemical Engineering Xi’an University of Science and TechnologyXi’anShaanxi 710054China

Coal gasification fine slag(CGFS)is a solid waste containing residual carbon and ash generated during the coal gasification process,and the separation of the two components is the essential way to realize its environmental pollution reduction and resource value *** flotation is the preferred method for separating CGFS,but there is a barrier of low carbon recovery in this process due to the extensive adsorption of collector by the well-developed pores on residual *** this study,a sufficiently simple yet innovative collector,a mixture of hydrophobic powder and diesel,was proposed in an attempt to break the *** experiments with common diesel and this novel collector were performed respectively,and FTIR,XPS,and SEM-EDX were employed to analyze the collector action *** results revealed that the novel collector could significantly improve the residual carbon recovery;test results demonstrated that the novel collector could increase the hydrophobic functional group content on the fine slag surface,and the hydrophobic powders in this novel collector mainly appeared at the pore openings of the flotation *** essence of the mechanism is that the hydrophobic powders play a dual role of blocking pores and providing adsorption sites,thus facilitating the spreading of diesel on the carbon surface and promoting its *** study can provide creative ideas for the efficient disposal of coal gasification waste.

关键词： Coal gasification fine slag Carbon recovery Collector Fotation Hydrophobic powder