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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 InstituteXi'an710077ShaanxiChina Key Laboratory of Oil and Gas Safety and Emergency Technology China University of PetroleumBeijing102249China Oil Production Technology Research Institute of Liaohe Oilfield Company Panjin124010LiaoningChina Tianjin Gas Storage Branch PetroChina Dagang Oilfield CompanyTianjin300280China Petroleum Production Engineering Research Institute Daqing Oilfield CompanyDaqing163712HeilongjiangChina

Erosion wear is a common failure mode in the oil and gas *** 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 *** 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 ***,it is not yet fully understood the erosion mechanism of pipe steel for hydraulic ***,this article provides a detailed analysis of the erosion behavior of fracturing pipes under complex working conditions based on experiments and numerical ***,we conducted erosion experiments on AISI 4135 steel for fracturing pipes to investigate the erosion characteristics of the *** effects of impact angle,flow velocity and applied stress on erosion wear were comprehensively *** 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 *** 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 *** 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

Laryngopharyngeal reflux in patients with reflux esophagitis

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World Journal of Gastroenterology 2008年第28期14卷 4523-4528页

作者： Yung-Chih lai Pa-Chun Wang jun-Chen Lin Division of Gastroenterology Department of Internal Medicine Cathay General Hospital School of Medicine National Taiwan University School of Medicine Taipei Medical University Taipei 10630 Taiwan China Department of Otolaryngology Cathay General Hospital School of Medicine Fu Jen Catholic University Taipei 10630 School of Public Health China Medical University Taichung 40402 Taiwan China Department of Otolaryngology Cathay General Hospital Taipei 10630 Taiwan China

AIM: To assess the prevalence of laryngopharyngeal reflux (LPR) in patients with reflux esophagitis and dis-close factors contributing to the development of LPR. METHODS: A total of 167 patients who proved to have reflux esophagitis by endoscopy were enrolled. They received laryngoscopy to grade the reflux find-ings for the diagnosis of LPR. We used validated ques-tionnaires to identify the presence of laryngopharyn-geal symptoms, and stringent criteria of inclusion to increase the specificity of laryngoscopic findings. The data of patients were analyzed statistically to find out factors related to LPR. RESULTS: The prevalence rate of LPR in studied sub-jects with reflux esophagitis was 23.9%. Age, hoarse- ness and hiatus hernia were factors significantly as-sociated with LPR. In 23 patients with a hiatus hernia, the group with LPR was found to have a lower trend of esophagitis grading. CONCLUSION: Laryngopharyngeal reflux is present in patients with reflux esophagitis, and three predicting factors were identified. However, the development of LPR might be different from that of reflux esophagi-tis. The importance of hiatus hernia deserves further study.

关键词： Laryngopharyngeal reflux Gastroesophageal reflux disease Reflux esophagitis

ANALYTICAL CHIP FORMATION MODEL OF MICRO-END-MILLING

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Chinese Journal of Mechanical Engineering 2008年第1期21卷 5-8页

作者： LI Chengfeng lai Xinmin LI Hongtao PENG Linfa NI jun School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200240 China Shien-ming Wu Manufacturing Research Center University of Michigan Michigan 48109 USA

A new analytical chip formation model is proposed for micro-end-milling operations. The model calculates an instantaneous uncut chip thickness by considering the combination of exact trochoidal trajectory of the tool tip and tool run-out, while the simplified circular trajectory and the neglected run-out create negligible change in conventional-scale chip formation models. Newton-Raphson iterative method is employed during the calculation to obtain quadratic convergence. The proposed approach allows the calculation of instantaneous uncut chip thickness to be done accurately and rapidly, and the prediction accuracy of this model is also verified by comparing the simulation results to experimental cutting forces.

关键词： Chip formation End-milling Run-out

Corrosion Behavior of Selective Laser Melted AISi10Mg Alloy in NaCl Solution and Its Dependence on Heat Treatment

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Acta Metallurgica Sinica(English Letters) 2020年第3期33卷 327-337页

作者： Xin-Hui Gu jun-Xi Zhang Xiao-Lei Fan lai-Chang Zhang Shanghai Key Laboratory of Material Protection and Advanced Material in Electric Power Shanghai University of Electric PowerShanghai 200090China School of Engineering Edith Cowan University270 Joondalup DriveJoondalupPerthWA 6027Australia

This work investigates the corrosion behavior of AlSilOMg alloy produced by selective laser melting(SLM) and the counterparts heat-treated at 450-550℃in 3.5 wt% NaCl *** measurements and weight loss tests together with microstructural characterizations were *** SLM-produced alloy displays a microstructure with a continuous network of Si particles,exhibiting superior corrosion *** heat treatment,the Si particles are coarsened and isolated and A1 matrix dissolves into their surrounding area,thereby degrading the corrosion resistance ***,the corrosion resistance of AlSilOMg alloy degrades with increasing the heat treatment temperature.

关键词： Aluminum Selective laser melting XRD Electrochemistry Pitting corrosion

Long non-coding RNA MEG3 regulates autophagy after cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2022年第4期17卷 824-831页

作者： Tian-Hao Li Hong-Wei Sun lai-jun Song Bo Yang Peng Zhang Dong-ming Yan Xian-Zhi Liu Yu-Ru Luo Department of Neurosurgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina

Severe cerebral ischemia/reperfusion injury has been shown to induce high-level autophagy and neuronal ***,it is extremely important to search for a target that inhibits autophagy *** non-coding RNA MEG3 participates in ***,it remains unclear whether it can be targeted to regulate cerebral ischemia/reperfusion *** results revealed that in oxygen and glucose deprivation/reoxygenation-treated HT22 cells,MEG3 expression was obviously upregulated,and autophagy was increased,while knockdown of MEG3 expression greatly reduced ***,MEG3 bound mi R-181 c-5 p and inhibited its expression,while mi R-181 c-5 p bound to autophagy-related gene ATG7 and inhibited its *** experiments revealed that mir-181 c-5 p overexpression reversed the effect of MEG3 on autophagy and ATG7 expression in HT22 cells subjected to oxygen and glucose deprivation/*** vivo experiments revealed that MEG3 knockdown suppressed autophagy,infarct volume and behavioral deficits in cerebral ischemia/reperfusion *** findings suggest that MEG3 knockdown inhibited autophagy and alleviated cerebral ischemia/reperfusion injury through the mi R-181 c-5 p/ATG7 signaling ***,MEG3 can be considered as an intervention target for the treatment of cerebral ischemia/reperfusion *** study was approved by the Animal Ethics Committee of the First Affiliated Hospital of Zhengzhou University,China(approval ***20190538)on January 4,2019.

关键词： ATG7 autophagy cerebral infarction cerebral ischemia/reperfusion injury long non-coding RNA miR-181c-5p neuron oxygen and glucose deprivation/reoxygenation

Vocal repertoire of the critically endangered whiteheaded langur(Trachypithecus leucocephalus): Call types, acoustic structures, and related social-ecological contexts

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Zoological Research 2022年第5期43卷 875-879页

作者： Peng-lai Fan Jia-Xing Li Li-Ting Yang Tao Sun Shi-jun Wu Cyril CGrueter Cheng-ming Huang Qi-Hai Zhou ming Li CAS Key Lab Animal Ecology&Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Guangxi Normal University) Ministry of EducationGuilinGuangxi 541006China Guangxi Key Laboratory of Rare and Endangered Animal Ecology College of Life SciencesGuangxi Normal UniversityGuilinGuangxi 541006China Guangxi Chongzuo White-headed Langur National Nature Reserve ChongzuoGuangxi 532200China Department of Anatomy Physiologyand Human BiologySchool of Human SciencesUniversity of Western AustraliaPerth WA 6009Australia Centre for Evolutionary Biology School of Biological SciencesUniversity of Western AustraliaPerth WA 6009Australia International Center of Biodiversity and Primate Conservation Dali UniversityDaliYunnan 671003China Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunmingYunnan 650223China

DEAR EDITOR,We examined the vocal repertoire of the critically endangered white-headed langur(Trachypithecus leucocephalus)inhabiting karst limestone forests in *** identified 17 call types across all age/sex classes based on human auditory perception,spectrogram assessment,and quantitative analysis of 25 acoustic parameters extracted from 409 high-quality *** total,11 types of calls produced by adults corresponded to the simple one-male multi-female social groups of white-headed langurs.

关键词： white critically karst

Effects of nociceptin/orphanin FQ on rats with cathartic colon

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World Journal of Gastroenterology 2007年第1期13卷 141-145页

作者： Hai-Yan Li Xiang Yan Quan-lai Xue Yong-Ning Zhou Yan Gao Rui Wang Yong-ming Liu jun-Tao Ran Department of Gastroenterology the Affiliated Hospital of Jinchuan Corporation Company Jinchang 737100 Gansu Province China Department of Geriatrics 1st Affiliated Hospital of LanzhouUnivercity Lanzhou 730000 Gansu Province China Department of Life Science Lanzhou UniversityLanzhou 730000 Gansu Province China

AIM： To demonstrate the change and effect of nodceptin/orphanin FQ in the colon of rats with cathartic colon. METHODS： The cathartic colon model was established by feeding rats rhubarb for 3 mo, the changes of colonic electromyography were investigated by both suspension muscle strips test and serosal recordings of colonic myoelectrical activity. Immunohistochemical staining （S-P methods） and image analysis were used to determine the changes of nociceptin/orphanin FQ in the proximal colon and distal colon of rats with cathartic colon. RESULTS： Suspension muscle strips test in vitro showed OFQ （10^-9-10^-6 mol/L） concentration dependently caused an immediate tonic contraction in the isolated colon. But the increase of tension in cathartic colon was less than control groups （P〈0.01）. Intravenous administration of OFQ （1 μg/kg） caused phasic contractions in the proximal colon, while the amplitude of phasic contractions caused by OFQ in cathartic colon was much lower than that in the control groups （2.58±0.41 vs 4.16 ± 0.53, t = -2.6, P = 0.012）. OFQ was highly expressed in the myenteric plexus of the rat colon but not in the musde cells. The immunoreactivity of OFQ in the proximal colon in cathartic colon rats decreased significantly compared with the control group （P = 0.001）. CONCLUSION： Colonic smooth muscle of cathartic colon showed low sensitivity to the stimulation of OFQ, suggesting that it might be caused by the abnormal distribution of OFQ or the abnormalities of receptors, leading to the disorganization of dynamic and incoordinated contractions.

关键词： Gastroenterology

Metachronous mixed cellularity classical Hodgkin’s lymphoma and T-cell leukemia/lymphoma: A case report

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World Journal of Clinical Cases 2021年第27期9卷 8177-8185页

作者： Yang Dong lai-jun Deng Mi-Mi Li Department of Clinical Pharmacy Weifang Hospital of Traditional Chinese MedicineWeifang 261000Shandong ProvinceChina Department of Hematology Weifang Hospital of Traditional Chinese MedicineWeifang 261000Shandong ProvinceChina Department of Pathology Weifang Hospital of Traditional Chinese MedicineWeifang 261000Shandong ProvinceChina

BACKGROUND The development of peripheral T-cell lymphoma(PTCL)after chemotherapy for Hodgkin’s lymphoma(HL)is rare,and highly aggressive TCL/leukemia has not been reported to *** relationship between HL and PTCL needs further exploration to understand the pathogenesis of metachronous lymphoma(ML)and find effective treatment *** report a patient with ML,whose biopsy of a right cervical lymph node initially confirmed classical HL(CHL).CASE SUMMARY We report a patient with ML,whose biopsy of a right cervical lymph node initially confirmed CHL,with typical reed–sternberg cells expressing CD30 and PAX-5.T-cell leukemia/lymphoma occurred 3 years after treatment,and a lymph node biopsy at the onset confirmed PTCL,nonspecific type,expressing CD3,CD4 and *** patient was treated with standard doses of chemotherapy,programmed cell death-ligand 1 monoclonal antibody,and chidamide,all of which failed to achieve complete *** patient was diagnosed with refractory state,and eventually died of leukocyte *** The accuracy of the diagnosis needs to be confirmed when chemotherapeutic drugs are not effective.

关键词： Classical Hodgkin’s lymphoma T-cell lymphoma/leukemia Bone marrow Chemotherapy Drug resistance Case report

Relationship of particle stimulated nucleation,recrystallization and mechanical properties responding to Fe and Si contents in hot-extruded 7055 aluminum alloys

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Journal of Materials Science & Technology 2019年第11期35卷 2570-2581页

作者： Huan She Da Shu Anping Dong jun Wang Baode Sun Hongchang lai Department of Implant Dentistry Shanghai Ninth People's HospitalCollege of StomatologyShanghai Jiao Tong University School of MedicineShanghai 200011China Shanghai Key Lab of Advanced High-temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Lab of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China

The variations of coarse intermetallic particles in hot-extruded 7055 aluminum alloys with 0.041 wt%Fe and 0.024 wt%Si increasing to 0.272 wt%Fe and 0.134 wt%Si were *** particle stimulated nucleation(PSN)behaviors for different kind of coarse particles were detailly analyzed by ***,the effect of PSN responding to Fe and Si contents on recrystallization and tensile properties of 7055 alloys was *** increasing Fe and Si contents,the size and number density of coarseη/S particles are reduced,while the number densities of coarse Al7Cu2 Fe and Mg2Si particles are both increased and the coarse Al7Cu2 Fe particles transform from rod-like to *** PSN recrystallized grains with predominant orientations deviated from the extruded fiber textures are stimulated by the irregular Al7Cu2 Fe and Mg2Si particles,because a higher degree of local non-uniform deformation is *** rod-like Al7Cu2 Fe particles cause the greatest degree of local non-uniform deformation owing to the largest aspect ratio,but the shape also restricts the area of particle deformation zone(PDZ)resulting in fewer PSN recrystallized *** irregularη/S particles give rise to the lowest degree of local non-uniform deformation and fewest PSN recrystallized grains with the major orientations close to the extruded fiber ***,despite the number and size of coarseη/S particles are reduced,the proportion of high angle grain boundaries(HAGBs)is increased and the extruded fiber textures are weakened with Fe and Si contents increasing,because of the increased Al7Cu2 Fe and Mg2Si *** strength is slightly declined by the weakened//ED(extrusion direction)fiber texture,while the elongation is reduced for a larger number of coarse particles and more HAGBs with higher Fe and Si contents.

关键词： 7055 aluminum alloy Particles Recrystallization Texture Mechanical properties