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A physically based methodology for predicting anisotropic creep properties of Ni-based superalloys

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Rare Metals 2016年第8期35卷 606-614页

作者： Jia Huang duo-Qi shi Xiao-guang Yang school of Energy and Power Engineering Beihang University

This paper is focused on developing suitable methodology for predicting creep characteristics （i.e., the minimum creep strain rate, stress rupture life and time to a specified creep strain） of typical Ni-based directionally solidified （Ds） and single-crystal （sC） superalloys. A modem method with high accuracy on simulating wide ranging creep properties was fully validated by a sufficient amount of experimental data, which was then developed to model anisotropic creep characteristics by introducing a simple orientation factor defined by the ultimate tensile strength （UTs）. Physical confidence on this methodology is provided by the well-predicted transitions of creep defor- mation mechanisms. Meanwhile, this method was further adopted to innovatively evaluate the creep properties of different materials from a relative perspective.

关键词： Wilshire equations Anisotropic creepproperties Ni-based superalloy Prediction methodologyCreep mechanism

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全球入侵植物的经济成本评估

草业学报 2024年第5期33卷 16-24页

作者：赵光华高明龙王朵范世奇唐健孙阔温玄烨山西师范大学生命科学学院山西太原030031 内蒙古农业大学林学院内蒙古呼和浩特010019 国家林业和草原局生物灾害防控中心辽宁沈阳110031 中国科学院植物研究所植被与环境变化国家重点实验室北京100093

植物是入侵生物中种类和数量最多的类群,对入侵植物开展经济成本评估可为后续风险管理和相关政策的制定提供参考依据。本研究基于InvaCost数据库评估获得了1970-2017年全球入侵植物的经济成本,研究结果表明:1)入侵植物的保守经济成本为1... 详细信息

植物是入侵生物中种类和数量最多的类群,对入侵植物开展经济成本评估可为后续风险管理和相关政策的制定提供参考依据。本研究基于InvaCost数据库评估获得了1970-2017年全球入侵植物的经济成本,研究结果表明:1)入侵植物的保守经济成本为1943.65亿美元,年均40.49亿美元,其中,直接经济损失达1004.68亿美元,占比为51.69%;2)在64个国家和地区中,美国的经济成本最高,其次为澳大利亚,我国208.31亿美元(1407.07亿人民币)排名第三。凤眼莲是全球最昂贵的入侵植物种类,其危害所产生的成本高于排名5~10名的入侵植物成本之和;3)过去的近50年里,入侵植物的经济成本呈上升趋势,模型测算2017年入侵植物的可能成本为34.38亿~104.52亿美元,最高置信值为77.25亿美元。本研究有助于加深对入侵植物危害严重性的客观认识,可为我国开展更为积极的入侵植物治理提供科学依据。

关键词：入侵植物经济成本 InvaCost数据库生物灾害损失评估

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Distinct pathogenic mechanisms of various RARs1 mutations in Pelizaeus-Merzbacher-like disease

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science China(Life sciences) 2021年第10期64卷 1645-1660页

作者： guang Li Gilbert Eriani En-duo Wang Xiao-Long Zhou state Key Laboratory of Molecular Biology CAS Center for Excellence in Molecular Cell ScienceShanghai Institute of Biochemistry and Cell BiologyChinese Academy of Sciences/University of Chinese Academy of SciencesShanghai 200031China Architecture et Réactivitéde l’ARN UPR9002 CNRSInstitut de Biologie Moléculaire et CellulaireUniversitéde Strasbourg67084 StrasbourgFrance school of Life science and Technology ShanghaiTech UniversityShanghai 201210China

Mutations of the genes encoding aminoacyl-tRNA synthetases are highly associated with various central nervous system *** mutations,including c.5A>G,p.D2G;c.1367C>T,p.s456L;c.1535G>A,p.R512Q and c.1846_1847del,p.Y616Lfs*6 of RARs1 gene,which encodes two forms of human cytoplasmic arginyl-tRNA synthetase(hArgRs),are linked to Pelizaeus-Merzbacher-like disease(PMLD)with unclear *** these mutations,c.5A>G is the most extensively reported mutation,leading to a p.D2G mutation in the N-terminal extension of the long-form ***,we showed the detrimental effects of R512Q substitution andΔC mutations on the structure and function of hArgRs,while the most frequent mutation c.5A>G,p.D2G acted in a different manner without impairing hArgRs *** nucleotide substitution c.5A>G reduced translation of hArgRs mRNA,and an upstream open reading frame contributed to the suppressed translation of the downstream main *** together,our results elucidated distinct pathogenic mechanisms of various RARs1 mutations in PMLD.

关键词： aminoacyl-tRNA synthetase(aaRs) central nervous system(CNs) protein biosynthesis translation initiation tRNA

基于二次雷达和射频技术在地铁辅助预警中的研究

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科教融合对创新性公共卫生人才培养影响机制探析

科学与信息化 2024年第8期 142-144页

作者：程光耀王志城尹铎北京市地铁运营有限公司北京 100079

通过在列车上安装二次雷达和射频天线(RFID),侦测前方列车距离,实现直线段300m以内报警,在切除ATP的情况下,通过声光告警的方式辅助司机驾驶.此措施实施后,可将辅助司机对前车安全距离的预判,提升列车在不受限于RM模式下25km/h的防护速... 详细信息

通过在列车上安装二次雷达和射频天线(RFID),侦测前方列车距离,实现直线段300m以内报警,在切除ATP的情况下,通过声光告警的方式辅助司机驾驶.此措施实施后,可将辅助司机对前车安全距离的预判,提升列车在不受限于RM模式下25km/h的防护速度运行时的安全性,期望列车运行速度由25km/h提升至40km/h,最大限度恢复行车秩序,降低对乘客出行的影响.

关键词：二次雷达技术 RFID技术地铁辅助防护

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现代预防医学 2024年第13期51卷 2491-2496页

作者：孔露诗胡光丽陈朵张锦丹成晓芬李贝南方医科大学卫生管理学院南方医科大学研究生学院

目的探讨科教融合理念认同对创新性公共卫生人才培养的影响，以期提出提升育人成效的有效措施。方法对某医科院校409名全日制公共卫生专业硕士进行问卷调查。使用IBM sPss22.0进行描述统计和数据分析，探索变量间的关系。结果该医科... 详细信息

目的探讨科教融合理念认同对创新性公共卫生人才培养的影响，以期提出提升育人成效的有效措施。方法对某医科院校409名全日制公共卫生专业硕士进行问卷调查。使用IBM sPss22.0进行描述统计和数据分析，探索变量间的关系。结果该医科院校公共卫生专业硕士科教融合理念认同度平均得分为（1.808±0.296）分，课堂实践情况平均得分为（2.194±0.327）分，科研参与情况平均得分为（2.458±0.313）分，人才培养综合得分的平均得分为（2.451±0.303）分。中介模型检验表明，理念认同度可直接正向影响人才培养综合得分，直接效应量为0.125(95%CI:0.046～0.205)；课堂实践情况在理念认同度与人才培养综合得分之间起部分中介作用，中介效应量为0.153(95%CI:0.006～0.160)，且理论认同度-课堂实践情况-科研参与情况-人才培养综合得分的链式中介作用也显著，中介效应量为0.075(95%CI:0.099～0.232)。结论学生对科教融合理论的认同不仅可以正向影响人才培养，还可以通过课堂实践的中介作用及课堂实践和科研参与的链式中介作用间接影响人才培养。

关键词：公共卫生人才培养科教融合创新性人才影响机制

Influence of Wave Direction on the Dynamic Response of A submarine Equipment Launch and Recovery system

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China Ocean Engineering 2022年第1期36卷 144-154页

作者： JIN Yong-ping XIE Kun LIU guang-ping WAN Bu-yan PENG You-duo National-Local Joint Engineering Laboratory of Marine Mineral Resources Exploration Equipment and safety Technology Hunan University of Science and TechnologyXiangtan 411201China

A launch and recovery system for a seafloor drill was studied using a dynamic model that considered the influences of seawater resistance and the elastic deformation of the cable based on the lumped mass *** influence of wave direction angle on heave,roll,and pitch motions of the ship was analyzed,and those motion characteristics were then used to assess the tension response of the armored umbilical cable at the lifting point under different wave direction *** analyzing the different wave direction angles we found that,when a ship experiences longitudinal waves it will express longitudinal *** a ship encounters transverse waves,it will have transverse *** oblique waves from bow or stern,a ship will have both longitudinal and transverse movement,exhibiting obvious heave and pitch *** waves,in this study,produced the most obvious impact on armored umbilical cable ***,the tension of the armored umbilical cable will change based on the weight of the armored umbilical cable and the seafloor drill in the *** analysis has provided a useful reference for the study of heave compensation and the constant tension automatic control.

关键词： seafloor drill elastic cable lumped mass method motion characteristics analysis

Multi-model coupling-based dynamic control system of ladle slag in argon blowing refining process

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Journal of Iron and steel Research International 2023年第5期30卷 926-936页

作者： guang-da Bao Ting Wu duo-gang Wang Xiao-bin Zhou Hai-chuan Wang school of Metallurgical Engineering Anhui University of TechnologyMa’anshan 243032AnhuiChina shanghai Meishan Iron and steel Co. Ltd.Nanjing 210039JiangsuChina

since the current slagging of argon blowing refining process is relatively fixed,which cannot adapt to the fluctuation of converter smelting process,it poses the problems of poor metallurgical property of refining slag and a large amount of molten *** optimization system coupled with multiple models was proposed to dynamic control the ladle slagging in the argon blowing refining *** can compile the optimal dynamic slagging scheme in real time under the guarantee of deoxidation performance and reasonable *** argon blowing refining slag composition range of CaO/Al_(2)O_(3)=1.3-1.7,CaO/siO_(2)=6-12,w(MgO)=2%-6% was determined based on FeO activity and liquidus temperature by equilibrium thermodynamic *** addition,it demonstrated better performance in the viscosity prediction task of the presented Visual Geometry Group 16-like one-dimensional convolutional neural network deep learning algorithm versus the Random Forest ensemble learning algorithm,as the adjusted coefficients of determination were 0.9712 and 0.9637,*** the system was applied in operation,the argon blowing refining process was stable,and the steel yield was enhanced,which promoted the intelligent steelmaking level while achieving the cost reduction and efficiency improvement.

关键词： Argon blowing refining process Deoxidation Viscosity model Deep learning Intelligent steelmaking

Microstructural evolution and restoration of creep property for a damaged K403 alloy after rejuvenation heat treatments

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Rare Metals 2021年第7期40卷 1865-1871页

作者： Liang Wang Xiao-guang Yang Hong-Yu Qi duo-Qi shi shao-Lin Li school of Energy and Power Engineering Beihang UniversityBeijing 100191China Beijing Key Laboratory of Aero-Engine structure and strength Beijing 100191China

Rejuvenation heat treatments can restore the microstructures and mechanical properties of the degraded turbine blades in gas turbine *** we analyze the effects of rejuvenation heat treatments on the microstructural characteristics and mechanical properties of damaged and undamaged specimens of a Ni-based superalloy,*** damaged specimens were found to have degraded microstructures and shorter creep lifetime than the undamaged *** rejuvenation heat treatment proved beneficial,especially for specimens exposed to damage for 50 *** addition,the microstructure recovery and creep life were found to depend on the predamage durations of the specimens.A y’-precipitate-based creep lifetime model was established to predict the residual lifetime based on the microstructural information.

关键词： Microstructural evolution Creep property Restoration Rejuvenation heat treatments

Constitutive modeling of a directionally solidified nickel-based superalloy DZ125 subjected to thermal mechanical creep fatigue loadings

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Rare Metals 2019年第10期38卷 922-936页

作者： Xiao-An Hu Xiao-guang Yang duo-Qi shi Hui-Chen Yu Ting-Ting Ren school of Energy and Power Engineering Beihang UniversityBeijing 100191China science and Technology on Advanced High Temperature structural Materials Laboratory Beijing Institute of Aeronautical MaterialsBeijing 100095China Air Force Armament Department China Aviation MuseumBeijing 102211China

A transversely isotropic continuum elasto-viscoplasticity model,which was developed from Chaboche’s unified constitutive model,was formulated to capture the thermal mechanical creep fatigue deformation behavior of a directionally solidified nickel-based superalloy.A fourthorder tensor was introduced to model material *** order to model the tertiary creep behavior,the Kachanov damage evolution equation was coupled into the stress *** on the test results of uniaxial tensile,fatigue,and creep loadings at isothermal temperature conditions,the material parameters are *** mechanical fatigue(TMF) and creep-fatigue interaction test results were used to verify the robustness of the ***,strain-temperature-dependent stress-strain responses under TMF loadings were analyzed using the present *** strain-controlled conditions,both of the stress ranges and mean stresses are strongly influenced by the strain-temperature phases,a key parameter for TMF tests.

关键词： Constitutive Thermal mechanical fatigue Creep Viscoplastic superalloy