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CYCLIC DEFORMATION BEHAVIOR OF ZIRCALOY-4 AT DIFFERENT TEMPERATURES

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Acta Metallurgica Sinica(English Letters) 1995年第3期8卷 219-225页

作者： xiAO Lin gu Haicheng KUANG Zhenbang(xi’an Jiaotong University, China xi'an Jiaotong Univ Xi'an China

Fatigue lifetime curves of Zircaloy-4 at different temperatures were measured, and the fatigued dislocation configurations were investigated using transmission electron microscopy. Ii was found that prismatic slip is the primary deformation mode. for Zircaloy-4fatigued at RT prismatic plus Pyramidal slip at 400℃,and prismatic plus (0001) basic slip at 600℃. The corresponding dislocation configurations are parallel dislocation lines al RT, elongated cells at 400℃ and two sets of mutually Perpendicular dislocation bands at 600℃.respectively. The relationship among. fatigue deformation mode, dislocation configuration and lifetime is discussed.

关键词： Zircaloy-4,.fatigue dislocation configuration slip system

TMSOTf-catalyzed intramolecular seleno-arylation of tethered alkenes:A novel method for the solid-phase synthesis of dihydrocoumarins and coumarins

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Chinese Chemical Letters 2012年第6期23卷 631-634页

作者： E Tang Wen Li Zhang Yong Gao xi gu Key Laboratory of Medicinal Chemistry of Natural Resource （Yunnan University） Ministry of Education China Department of Applied Chemistry Yunnan University Kunming 650091 China

TMSOTf-catalyzed intramolecular seleno-arylation of tethered alkenes was performed using polystyrene-supported succini- midyl selenide as the selenium source. This catalytic process provides an efficient method for the regioselective synthesis of dihydrocoumarins possessing a seleno-functionality, followed by traceless cleavage of selenium linker to provide dihydrocoumar- ins and coumarins in good yields and purifies.

关键词： Lewis acid Seleno-arylation Succinimidyl selenide Solid-phase synthesis Dihydrocoumarins Coumarins

Radiation efficiency and energy distribution from a borehole dipole source in the vertical transverse isotropic formation

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Petroleum Science 2024年第6期21卷 4034-4051页

作者： xi-Hao gu Fan-Tong Kong Yuan-Da Su xiao-Ming Tang School of Geosciences China University of Petroleum(East China) Centre for Exploration Geophysics Curtin University Ocean College Jiangsu University of Science and Technology Laoshan Laboratory

Dipole Shear-Wave Reflection Survey(DSRS) has gained wide application in identifying unconventional reservoirs in anisotropic formations. Previous investigations have illuminated how boreholes complicate the distribution of acoustic energy. However, these models have not accounted for the anisotropic context, rendering them insufficient for analyzing acoustic energy distribution and radiation efficiency in anisotropic formations. We derive expressions for energy flux and radiation efficiency from a borehole dipole source in the vertical-transverse isotropic(VTI) media using the Umov-Poynting vector and steepest-descent solution. Utilizing this approach, we systematically evaluate the sensitivity of anisotropic parameters to energy flux and radiation efficiency, unveiling intricate variations of these properties across frequency and anisotropic parameters. Our findings emphasize the substantial influence of formation anisotropy on energy distribution from a dipole source inside the borehole. Due to energy conversion between wave modes, five radiation wave modes are elicited by the dipole source, with the SH wave retaining its status as the prime candidate for DSRS in fast formations owing to its elevated radiation efficiency. Conversely, the qP-qP wave exhibits advantages over S waves in unconsolidated formations. A key distinction between isotropic and anisotropic media is the presence of dominant excitation frequencies in the low-frequency domain. The significance of dominant excitation-frequency bands is validated by field data, emphasizing their pivotal role. These results offer valuable insights for designing DSRS measurement strategies, which have broad application expectations for unconventional oil and gas exploration.

关键词： Dipole source Shear-wave reflection survey Anisotropic formation Energy flux Radiation efficiency

Anisotropic corrosion resistance of TiC reinforced Ni-based composites fabricated by selective laser melting

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Journal of Materials Science & Technology 2019年第6期35卷 1128-1136页

作者： Hongmei Zhang Dongdong gu Lixia xi Han Zhang Mujian xia Chenglong Ma College of Materials Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China Jiangsu Provincial Engineering Laboratory for Laser Additive Manufacturing of High-Performance Metallic Components Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Electrochemical measurements on three planes of TiC/Inconel 718 composites fabricated by selective laser melting(SLM) were performed to study the corrosion property. The results showed that the YZplane with dense and fine columnar structures possessed high microhardness and superior corrosion resistance in 3.5 wt% NaCl solution. For the XZ-plane, a decreased anti-corrosion property was observed owing to its inhomogeneous microstructures. While the XY-plane with large irregular pores and clustered ring-like structures was more susceptible to corrosion compared with the other two planes. Comparative analysis suggested that the anisotropic corrosion behaviors were significantly dependent on the surface defects, microstructure characteristics and added reinforcements.

关键词： Selective laser melting Corrosion resistance Nickel based composite Microstructure

Fracture mechanics analysis on Smart-Cut~*** 2:Effect of bonding flaws

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Acta Mechanica Sinica 2009年第2期25卷 197-203页

作者： Bin gu Hongyuan Liu Yiu-Wing Mai xi Qiao Feng ShouWen Yu Centre for Advanced Materials Technology (CAMT) School of Aerospace Mechanical and MechatronicEngineering (AMME) J07 University of SydneySydney NSW 2006 Australia Department of Engineering Mechanics Tsinghua University Beijing 100084 China

In Part 2 of the paper on the Smart-Cut process, the effects of bonding flaws characterized by the size and internal pressure before and after splitting are studied by using fracture mechanics models. It is found that the bonding flaws with large size are prone to cause severe deviation of defect growth, leading to a non-transferred area of thin layer when splitting. In a practical Smart-Cut process where the internal pressure of bonding flaws is very small, large interfacial defects always promote defect growth in the splitting process. Meanwhile, increasing the internal pressure of the bonding flaws decreases the defect growth and its deviation before splitting. The mechanism of relaxation of stiffener constraint is proposed to clarify the effect of bonding flaws. Moreover, the progress of the splitting process is analyzed when bonding flaws are present. After splitting, those bonding flaws with large size and high internal pressure are vulnerable for the blistering of the thin film during high-temperature annealing.

关键词： Smart-Cut technology Fracture mechanics Stress intensity factor Interfacial defect

Effects and mechanisms of nutritional interventions on extradigestive complications in obese patients

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World Journal of Gastrointestinal Surgery 2023年第11期15卷 2482-2489页

作者： Li Jiang Lu-Lian Xu Yang Lu Ke-Feng gu shu-Yi Qian xi-Ping Wang Xu Xu Department of Endocrine Wuxi Children’s HospitalWuxi 214023Jiangsu ProvinceChina

BACKGROUND Obesity is associated with an increased risk of multiple extradigestive ***,understanding the global epidemiology of obesity and its relation-ship with extradigestive complications,such as cardiovascular disease,type 2 diabetes mellitus,and non-alcoholic fatty liver disease is ***,nutritional intervention can positively manage issues associated with ***,the identification of the current high prevalence of extradigestive complica-tions among patients with obesity and the potential role of nutritional inter-ventions is also *** To determine the relationship between obesity and extradigestive complications and emphasize the importance of nutritional interventions in the management of patients with *** Overall,110 patients with obesity admitted to our hospital from February 2020 to November 2022 and 100 healthy individuals were included in the present *** of the study population,including demographic characteristics,such as age,sex,body mass index,indicators of extradigestive complications,dietary intake,and biomarkers was *** study design,participant selection,interventions,and development of the nutritional intervention program were *** collected data were analyzed to assess the effect of nutritional inter-ventions on extradigestive *** As a part of nutritional intervention,the dietary structure was modified to decrease the saturated fatty acid and cholesterol intake and increase the dietary fiber and polyunsaturated fatty acid intake to improve the blood lipid levels and cardiovascular *** studies showed that these nutritional inter-ventions positively affected mechanisms that regulate lipid metabolism,improved inflammatory markers in the blood,and improved vascular *** The study discusses the consistency of the present results with previous findings to assess the clinical significance of the present ***

关键词： Obesity Nutritional interventions Extradigestive complications Cardiovascular disease Type 2 diabetes Non-alcoholic fatty liver disease

Synthesis and Characterization of Poly (ether imide)s Containing Phthalazinone and Isopropyl Moieties

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Chinese Chemical Letters 2001年第7期12卷 593-594页

作者： Jin Yan WANG xi Gao JIAN shu De xiAO Department of Polymer Science&Material College of Chemical EngineeringDalian University of TechnologyDalian 116012

A novel poly(ether imide)s containing phthalazinone and isopropyl moieties derived from 2-(4-aminophenyl)-4-[4-(4-aminophenoxy)phenyl]-phthalazin-1-one and bisphenol-A diphthalic anhydride was synthesized by one-step solution condensation polymerization in nr-cresol. The polymer was characterized by FTIR, NMR, molecular weights, glass transition temperature, thermal degradation temperature and WAXD.

关键词： Poly (ether imide) s phthalazinone one-step solution condensation polymerization

Inclusions in wrought superalloys:a review

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Journal of Iron and Steel Research International 2021年第8期28卷 921-937页

作者： shu-feng Yang shu-lei Yang Jing-long Qu Jin-hui Du Yu gu Peng Zhao Ning Wang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Gaona Aero Material Co. Ltd.Beijing 100081China

Inclusions in wrought superalloys significantly affect the stability of the alloy properties and limit their use and devel-opment in aeroengines and other *** types and sources of inclusions in wrought superalloys were reviewed with analysis of the conditions of inclusion formation from the viewpoints of thermodynamics and *** ther-modynamic data for inclusion formation in nickel-based and cobalt-based alloys were summarized and *** damage of inclusions to the fatigue and tensile properties and workability of these alloys and the mechanisms of crack initiation and propagation caused by inclusions were also discussed,and the effects of inclusions with different charac-teristics on crack propagation were *** addition,the control methods and mechanisms of inclusions in the triple smelting process(vacuum induction melting+protective electroslag remelting+vacuum arc remelting)were covered,providing a reference for improving the control technology of inclusions in wrought ***,the difficulties and development trends for inclusion control in wrought superalloys were discussed.

关键词： Wrought superalloy Triple smelting Inclusion Control method

Phase Evolution of Cubic ZnS Annealed in Mild Oxidizing Atmosphere

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Chinese Physics Letters 2012年第3期29卷 227-230页

作者： XUE shu-Wen ZHANG Jun SHAO Le-xi Department of Physics Zhanjiang Normal CollegeZhanjiang 524048

ZnS thin films are prepared by thermal evaporation of high-purity ZnS powder on quartz glass *** samples were annealed in floating argon at temperatures from 300℃to 900℃.The effects of annealing temperature on the structural and optical properties were investigated by x-ray diffraction(XRD),scanning electron microscope(SEM)and optical *** results show that annealing below 500℃is beneficial to improve the quality of ZnS *** the annealing temperature exceeds 500℃,ZnS is gradually oxidized into ZnSO4,which has evident influences on the structural and optical properties of ZnS films.

关键词： annealing purity floating