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Biaxial tensile behavior of Ti-6Al-4V under proportional loading

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Chinese Journal of Aeronautics 2023年第5期36卷 344-362页

作者： Lin QI Yazhou GUO Kanghua JIN Huaipu KANG Yulong LI School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of Impact Dynamics and Engineering Applications Northwestern Polytechnical UniversityXi’an 710072China School of Civil Aviation Northwestern Polytechnical UniversitySuzhou 215699China NPU yangzi River Delta Research institute Suzhou 215400China

The biaxial tensile behavior of isotropic Ti-6Al-4 V is characterized in this paper.A novel cruciform specimen was designed and optimized to achieve uniform stress and strain distribution within the gauge area.Biaxial tensile tests were conducted at three different loading ratios by the biaxial testing machine.The Digital Image Correlation(DIC)technique was applied to determine strain distribution,and a high-speed camera was employed to record the fracture process.An Inverse Analysis(IA)approach with a combined experimental and numerical method was proposed to determine the true stresses at the gauge section of the specimen during biaxial tensile tests.The results indicate that the initial yield locus can be described by the Cazacu criterion accurately,whereas the Mises criterion can predict better the strengthening behavior of Ti-6Al-4 V in the first quadrant in the principal stress space.

关键词： Biaxial tensile testing Inverse analysis Strengthening behavior Ti-6Al-4V Yield locus

Application of Hydrocracking Process for Upgrading Tail Oil Quality in 1.0 Mt/a Hydrocracker Unit at SINOPEC yangzi Petrochemical Company

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China Petroleum Processing & Petrochemical Technology 2009年第1期11卷 13-17页

作者： Zhang Haichun Dong Jianwei SINOPEC yangzi Petrochemical Company Nanjing 210048 SINOPEC Research institute of Petroleum Processing

This article focuses on the hydrocracking technology for upgrading the quality of tail oil and the first commercial application of the RN-32V/RHC-1 catalysts in the 1.0 Mt/a hydrocracker at the yangzi Petrochemical Company, which was started up successfully in September 2008. One month after start-up of the hydrocracking unit, an evaluation operation has been conducted for assessing the catalysts performance. The technical calibration results showed that the RN-32V/RHC-1 catalysts had high activity, and the product yield distribution was reasonable. The hydrocracker can provide abundant feedstocks for the downstream aromatic production unit and ethylene production unit.

关键词：扬子石化公司商业应用加氢裂化工艺油质量加氢装置加氢裂化装置加氢裂化技术乙烯生产装置

Eu-Chelate Construct Ultrasensitive Time-Resolved Fluoroimmunoassay-Assay of Pepsinogen I

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Journal of Rare Earths 2006年第3期24卷 381-384页

作者：黄飚张祥瑞朱岚刘海燕蒋叶华金坚 Jiangsu institute of Nuclear Medicine Wuxi 214063 ChinaKey Laboratory of Industrial Biotechnology Ministry of Education Southern Yangzi University Wuxi 214036 China Jiangsu institute of Nuclear Medicine Wuxi 214063 China Key Laboratory of Industrial Biotechnology Ministry of Education Southern Yangzi University Wuxi 214036 China

Eu-chelate were used to construct a two-site sandwich-type assay for pepsinogen Ⅰ （PGI） with time-resolved fluoroimmunoassay （TRFIA） as a detection technique. On the noncompetitive assay, captured monoclonal antibodies （McAbs） coated on wells were directed against a specific antigenic site on the PGI. Another McAbs, called as labeling McAbs, were prepared with the Eu-chelate of N-（p-isothiocyanatobenzyl）-diethylenetriamine-N, N, N, N-tetraacetic acid and directed against a different antigenic site on the PGI. The fluorescence counts of bound Eu^3＋ -McAbs were measured with the auto DELFIA1235 system. The PGI in sera from healthy volunteers were determined by PGI-TRFIA. The within-run and between-run CVs of the PGI-TRFIA were 1.9% and 4.7%, respectively, and the recovery rate was 102.65%. The assay had a detection limit of 0.05 μg· L^-1. The PGI-TRFIA provided a linear response from 3.5 to 328 μg· L^-1. The cross-reacting rate with pepsinogen Ⅱ was negligible. The linear correlation of PGI-TRFIA and radioimmunassay measurements resulted in a correlation coefficient of 0.977. The means of healthy volunteers were 154 ±43 μg·L^-1 for serum PGI. The availability of a highly sensitive, reliable, and convenient method for quantifying PGI will allow investigations into the possible diagnostic value of this analyte in various clinical conditions, including gastric carcinoma, duodenal ulcer, gastritis and severe atrophic gastritis.

关键词： time-resolved fluoroimmunoassay pepsinogen Ⅰ Eu-chelate rare earths

Effects of surface topography and specimen thickness on high-speed raindrop impact damage of CFRP laminates

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Chinese Journal of Aeronautics 2023年第6期36卷 186-200页

作者： Naidan HOU Renxi ZHAO Xuan WANG Zhongbin TANG Hao CUI Yulong LI School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China Joint International Research Laboratory of Impact Dynamics and Engineering Application Xi'an 710072China Shaanxi Key Laboratory of Impact Dynamics and Engineering Application Xi'an 710072China School of Civil Aviation Northwestern Polytechnical UniversitySuzhou 215400China NPU yangzi River Delta Research institute Suzhou 215400China

Raindrop impact erosion has been observed since early days of aviation,and can be catastrophic for exposed materials during supersonic flight.A single impact waterjet apparatus is established for mimicking drop impacts at the velocities between 350 m/s and 620 m/s.Carbon Fiber Reinforced Polymer(CFRP)laminates with three different surface morphologies and specimen thicknesses are tested here.A central region with no visible damage has been noticed,surrounded by a"failure ring"with common damage patterns including resin removal,matrix cracking,fiber breakage and mass fiber loss.Asymmetric features are presented in the"failure ring"whose whole scope extends larger along the longitudinal direction than the transverse direction of the top layer.The mechanism of the resin removal is related to fiber-matrix debonding,and its onset and propagation can be facilitated by initial surface asperities with the shear action of the lateral jetting.In cases of multiple impact,good surface quality can slow down the evolution of resin removal and fiber exposure on the CFRP surface,reducing the erosion speed and delaying the occurrence of structural damages in the subsequent impacts.Rayleigh wave dominates the occurrence of matrix cracking on the CFRP surface,and subsequently,results in material loss and peeling of the top-layer because of lateral flow.With the increase of the specimen thickness,both the interlaminar and intralaminar failures decrease as the impact damage mechanism changes from plate bending stress to the reflection of stress waves.

关键词： Carbon fiber reinforced plastics Failure analysis Impact testing Lateral jetting Surface roughness Waterjet

Recent Advances on the Electrochemical Difunctionalization of Alkenes/Alkynes

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Chinese Journal of Chemistry 2019年第3期37卷 292-301页

作者： Haibo Mei Zizhen Yin Jiang Liu Hailong Sun Jianlin Han College of Chemical Engineering Nanjing Forestry UniversityNanjingJiangsu 210037China Nanjing Research institute of Sinopec yangzi Petrochemical Co. Ltd.NanjingJiangsu 210048China Nanjing University University of Oklahoma Texas Tech University

Electroorganic synthesis is an emerging area of high impact research in organic chemistry, which is considered as one of the green and efficient methods and attracts growing research attention. In this review, we summarized comprehensively the recent literature reports on the electrochemical oxidative difunctionalization of unsaturated C—C bonds. The reaction types described in this review included electrochemical intermolecular cyclization, electrochemical intramolecular cyclization, and electrochemical difunctionalization of alkenes/alkynes. This review focuses on the discussion of its synthetic generality for the preparation of functionalized compounds and the related electrochemical oxidative reaction mechanism.

关键词： Electrochemical Difunctionalization Alkenes/Alkynes

Study on design pressure of in-service welding pipes

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Science China(Technological Sciences) 2006年第4期49卷 434-444页

作者： XUE Xiaolong1, ZHU Jiagui2 & SANG Zhifu1 1. College of Mechanical and Power Engineering, Nanjing University of Technology, Nanjing 210009, China 2. Nanjing yangzi Petrochemical Maintenance and Installation Co. Ltd., Nanjing 210048, China College of Mechanical and Power Engineering Nanjing University of Technology Nanjing China Nanjing yangzi Petrochemical Maintenance and Installation Co. Ltd. Nanjing China

A method of predicting design pressure and burn-through of in-service welding pipes was established. Temperature distributions of in-service welding under variable parameters were simulated by FEM. The effect of flowing of internal media was regarded as forced convection. Based on the numerical results, design pressure of the pipe can be obtained and burn-through can be predicted. It can be concluded that the design pressure decreases with the increasing of heat input. RSF and design pressure of the pipe increase with the increasing of flow rate. There is a range in which the increase changes greatly. For in-service welding, the range should be considered adequately to determine operating condition optimally. RSF increases with the increasing of pipe wall thickness. While the thickness increases to an extent, RSF shows little increase. Accord- ing to the curves of design pressure versus different parameters, safe working pressure can be achieved.

关键词： in-service welding, heat input, flow rate, pipe wall thickness, design pressure.

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Bone Research 2024年第1期12卷 122-136页

作者： Nan-Yu Zou Ran Liu Mei Huang Yu-Rui Jiao Jie Wei yangzi Jiang Wen-Zhen He Min Huang Yi-Li Xu Ling Liu Yu-Chen Sun Mi Yang Qi Guo Yan Huang Tian Su Ye Xiao Wei-Shan Wang Chao Zeng Guang-Hua Lei Xiang-Hang Luo Chang-Jun Li Department of Endocrinology Endocrinology Research CenterXiangya Hospital of Central South UniversityChangshaHunan 410008China Department of Orthopaedics Xiangya Hospital of Central South UniversityChangshaHunan 410008China Department of Epidemiology and Health Statistics Xiangya School of Public HealthCentral South UniversityChangshaChina Hunan Key Laboratory of Joint Degeneration and Injury ChangshaHunan 410008China Key Laboratory of Aging-related Bone and Joint Diseases Prevention and Treatment Ministry of EducationXiangya HospitalCentral South UniversityChangshaChina School of Biomedical Sciences Institute for Tissue Engineering and Regenerative MedicineFaculty of MedicineThe Chinese University of Hong KongHong Kong SARChina Department of Orthopaedics The First Affiliated Hospital of Shihezi UniversityShiheziXinjiangChina National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangshaHunan 410008China

Skeletal stem/progenitor cell(SSPC)senescence is a major cause of decreased bone regenerative potential with aging,but the causes of SSPC senescence remain unclear.In this study,we revealed that macrophages in calluses secrete prosenescent factors,including grancalcin(GCA),during aging,which triggers SSPC senescence and impairs fracture healing.Local injection of human rGCA in young mice induced SSPC senescence and delayed fracture repair.Genetic deletion of Gca in monocytes/macrophages was sufficient to rejuvenate fracture repair in aged mice and alleviate SSPC senescence.Mechanistically,GCA binds to the plexin-B2 receptor and activates Arg2-mediated mitochondrial dysfunction,resulting in cellular senescence.Depletion of Plxnb2 in SSPCs impaired fracture healing.Administration of GCA-neutralizing antibody enhanced fracture healing in aged mice.Thus,our study revealed that senescent macrophages within calluses secrete GCA to trigger SSPC secondary senescence,and GCA neutralization represents a promising therapy for nonunion or delayed union in elderly individuals.

关键词： healing union senescence

Unusual Patterns of Neural Tube Defects in a High Risk Region of Northern China

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Biomedical and Environmental Sciences 2009年第4期22卷 340-344页

作者： GONG CHEN LI-JUN PEI JIAN HUANG XIN-MING SONG LIANG-MING LIN XUE GU JIAN-XIN WU FANG WANG JI-LEI WU JIA-PENG CHEN JU-FEN LIU RUO-LEI XIN TING ZHANG XIAO-YING ZHENG institute of Population Research Peking University Beijing 100871 China institute of Nutrition and Food Safety Chinese Center for Disease Control and Prevention Beijing 100050 China Capital institute of Pediatrics Beijing 100020 China

Objective To study the prevalence of different types of neural tube defects （NTDs） in Luliang Prefecture, Shanxi province, where the prevalence of NTDs is unusually high and the correlation between NTDs prevalence and patterns. Methods A surveillance population-based birth defects was performed in Luliang Prefecture, Shanxi province. Results The results of our study showed that the prevalence of NTDs was 2-fold higher in Luliang Prefecture than in other areas of Shanxi province. Unusual patterns of NTDs were found, however, multiple NTDs were relatively common in Luliang Prefecture, accounting for over 13% of all NTDs cases in China. Conclusion The prevalence of NTDs is associated with its patterns.

关键词： Neural tube defects Epidemiology Geographic variation

Direct extraction of equivalent circuit parameters for on-chip spiral transformers

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Journal of Semiconductors 2012年第1期33卷 149-154页

作者：韦家驹王志功李智群 institute of RF-&OE-ICs Southeast University Nanjing 210096China institute of RF-&OE-ICs Southeast University Nanjing 210096China

This paper compares model differences of transformers measured in 4-port and 2-port configurations. Although 2-port configuration is more appropriate for measurement and application, it brings tremendous difficul- ties to the model＇s parameter extraction. In this paper, a physics-based equivalent circuit model and its correspond- ing direct extraction procedure are proposed for on-chip transformers. The extraction is based on the measurement of 2-port configuration instead of the 4-port type, and it can capture the model parameters without any optimiza- tion. In this procedure, a new method has been developed for the parameter extraction of the ladder circuit, which is commonly used to represent the skin effect. Thus, this method can be transferred to the modeling of other passive devices, such as on-chip transmission lines, inductors, baluns, etc. In order to verify the procedure＇s efficiency and accuracy, an on-chip interleaved transformer in a 90 nm 1P9M CMOS process has been fabricated. We compare the modeled and measured self-inductance, the quality factor, mutual reactive and resistive coupling coefficients. Excellent agreement has been found over a broad frequency range.

关键词： transformer model extraction equivalent circuit ladder skin effect