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Hot Deformation Characteristics for a Nickel-base Superalloy GH742y

Journal of Materials Science & Technology 2009年第3期25卷 373-378页

作者： Fuwei Kang Jianfei Sun guoqing zhang Zhou Li School of Material Science and Engineering Harbin Institute of Technology Harbin 150001 China School of Material Science and Engineering Harbin University of Science and Technology Harbin 150040 China Beijing Institute of Aeronautical Materials Beijing 100095 China

The hot deformation characteristics of as-cast nickel-base superalloy GH742y after hot isostatic pressing （HIP）（hereafter referred to as-cast alloy） have been investigated by hot compression tests in the temperature range of 1050 to 1140℃, strain rate range of 0.01 s^-1 to 10 s^-1 and strain range of 35% to 50% by means of Gleeble-3500 thermal mechanical simulator. The results show that the as-cast alloy exhibits the poor deformability, and shows wedge-shaped cracking beyond the strain of 35%. At strain rates less than 1.0 s^-1, the stress-strain curves exhibit nearly steady-state behavior, while at strain rate of 10 s^-1, a yield drop and serrated yielding occur. The activation energy values developed on the basis of the experimental data are divided into three domains. The first domain appears at lower strain rate （≤1.0 s^-1） and lower temperature （≤1080℃）, with the lowest mean value of activation energy about 261.4 kJ/mol. The second domain appears at the same strain rate as the first domain, but higher temperature （〉1080℃）, with the intermediate mean value of activation energy about 328.8 k J/tool. The third domain appears at higher strain rate （10 s^-1） and temperature range of 1050 to 1140℃, with the largest mean value of activation energy about 605.05 kJ/mol. Three different constitutive equations are established in corresponding to domains. Microstructural observations in the third domain reveal non-uniform dynamic recrystallization （DRX） of homogeneous γ phase, which leads to the poor deformability and the highest Q value. In contrast, microstructures in the first domain show fully DRX of homogeneous γ phase, leading to the better deformability and the lowest Q value. It is noted that the grain size increases with the increment of strain rate or temperature. These results suggest that bulk metal working of this material may be carried out in the first domain where fully DRX of γ homogeneous occurred.

关键词： Superalloy Hot deformation Constitutive equation Activation energy

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“通督调神”法针刺治疗主观性耳鸣:随机对照试验

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中国针灸 2024年第6期44卷 648-652页

作者：李成龙茅伟张利达张鑫吴海洋张国庆张君宇王颖韩为安徽中医药大学第一临床医学院合肥230012 广州医科大学附属脑科医院中医科南京市高淳区中医院针灸科安徽中医药大学第二附属医院脑病科合肥230001 安徽中医药大学第二附属医院老年病科合肥230001 安徽省名中医王颖工作室合肥230001

目的:观察“通督调神”法针刺治疗主观性耳鸣的临床疗效,并探讨其可能的作用机制。方法:将92例主观性耳鸣患者随机分为针刺组(46例,脱落5例)和药物组(46例,脱落2例)。针刺组予“通督调神”法针刺治疗,穴取水沟、印堂、神庭、百会、风府... 详细信息

目的:观察“通督调神”法针刺治疗主观性耳鸣的临床疗效,并探讨其可能的作用机制。方法:将92例主观性耳鸣患者随机分为针刺组(46例,脱落5例)和药物组(46例,脱落2例)。针刺组予“通督调神”法针刺治疗,穴取水沟、印堂、神庭、百会、风府、大椎和患侧中渚、听会、翳风,每次30 min,隔日1次,每周3次;药物组予口服银杏叶片(40mg/次)、甲钴胺片(0.5mg/次),均每日3次。两组均连续治疗4周。观察两组患者治疗前后耳鸣严重程度评分、耳鸣响度视觉模拟量表(VAS)评分和情绪自评量表(DASS-21)评分,检测治疗前后两组患者血清脑源性神经营养因子(BDNF)含量,并评定临床疗效。结果:治疗后,两组患者耳鸣严重程度评分、耳鸣响度VAS评分和DASS-21评分均较治疗前降低(P<0.01),且针刺组均低于药物组(P<0.05)。治疗后,两组患者血清BDNF含量均较治疗前降低(P<0.01),且针刺组低于药物组(P<0.05)。针刺组总有效率为82.9%(34/41),高于药物组的70.5%(31/44,P<0.05)。结论:“通督调神”法针刺可改善主观性耳鸣患者的耳鸣严重程度、耳鸣响度和不良情绪,其机制可能与调节血清BDNF含量、影响听觉中枢可塑性有关。

关键词：主观性耳鸣针刺通督调神视觉模拟量表评分脑源性神经营养因子随机对照试验

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FATIGUE LIFE PREDICTION OF CRANKSHAFT MADE OF MATERIAL 48MnV BASED ON FATIGUE TESTS,DYNAMIC SIMULATION AND FEA

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Chinese Journal of Mechanical Engineering 2006年第2期19卷 307-311页

作者： zhang guoqing PU Gengqiang WANG Chengtao Life Quality and Mechanical Engineering Institute Shanghai Jiaotong UniversityShanghai 200030 China

S-N curve and fatigue parameters of 48MnV are obtained using small sample tests and staircase or up and down method, which paves the way for predicting fatigue life of crankshaft made of 48MnV. The fatigue life of the crankshaft of a six-cylinder engine is calculated using different damage models such as S-N method, normal strain approach, Smoth-Watson-Topper （SWT）Bannantine approach, shear strain approach, and Fatemi-Socie method based on dynamic simulation and finite element analysis （FEA） of crankshaft. The results indicate that the traditional calculation is conservative and the residual fatigue life of crankshaft is sufficient to maintain next life cycle if the crankshaft is remanufactured after its end of life.

关键词： 48MnV Multiaxial fatigue Crankshaft Dynamic simulation Finite element analysis (FEA)

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运动引起的脑震荡与神经退行性疾病的关联

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当代体育科技 2024年第24期14卷 11-13页

作者：孟庆峰张国庆吉林师范大学吉林四平136000

脑震荡不仅在急性期内对脑功能产生影响,重复性脑震荡还可能导致长期的神经退行性病变,如阿尔茨海默病、帕金森病和慢性创伤性脑病(CTE)。研究系统分析了脑震荡的病理机制,包括机械损伤、代谢紊乱、血脑屏障功能障碍及神经炎症反应,探... 详细信息

脑震荡不仅在急性期内对脑功能产生影响,重复性脑震荡还可能导致长期的神经退行性病变,如阿尔茨海默病、帕金森病和慢性创伤性脑病(CTE)。研究系统分析了脑震荡的病理机制,包括机械损伤、代谢紊乱、血脑屏障功能障碍及神经炎症反应,探讨了其与神经退行性疾病的关联。此外,通过流行病学调查,揭示了职业运动员中神经退行性疾病的高发风险,强调了脑震荡的累积效应及其对长期健康的影响。研究结果对制定有效的预防和干预措施具有重要意义。

关键词：脑震荡神经退行性疾病阿尔茨海默病脑损伤

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多波束声呐数据处理与三维地图构建的应用

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集成电路应用 2024年第6期41卷 54-55页

作者：李海英张国清胜利信科(山东)勘察测绘有限公司山东257000

阐述通过多波束声呐数据处理与三维地图构建的应用,构建出精确且详细的海底地形模型。基于案例分析,探讨信号处理、数据处理速度、自动化智能识别在提升测绘精度和效率方面的应用。

关键词：多波束声呐海底地形测绘三维地图构建数据处理

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A robust but variable lake expansion on the Tibetan Plateau

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Science Bulletin 2019年第18期64卷 1306-1309页

作者： guoqing zhang Wei Luo Wenfeng Chen Guoxiong Zheng Key Laboratory of Tibetan Environmental Changes and Land Surface Processes.Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China

Lakes on the Tibetan Plateau(TP)are an indicator and sentinel of climatic changes[1].We extended lake area changes on the TP from 2010[2]to 2018,and provided a long and dense lake observations between the 1970s and *** found that the number of lakes,with area larger than 1 km2,has in creased to?1,400 in 2018 from?1,000 in the *** total area of these lakes decreased between the 1970s and?1995,and then showed a robust increase,with the exception of a slight decrease in *** expansion of the lakes on the highest plateau in rhe world is a response to a hydrological cycle intensified by recent climate changes[3].

关键词： Plateau Tibetan intensified

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Finite-Element Simulation and Experimental Research of the Hot-Press Sintering of Nano-Sized Ceramic Powders

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Journal of Materials Science & Technology 2003年第z1期19卷 40-42页

作者： guoqing CHEN Kaifeng zhang Guofeng WANG Yandong YU Department of Materials Engineering Harbin Institute of Technology Harbin 150001 China Department of Materials Engineering Harbin Institute of Technology Harbin 150001 China Department of Materials Engineering Harbin Institute of Technology Harbin 150001 China Department of Materials Engineering Harbin Institute of Technology Harbin 150001 China

Numerical simulation of hot-press sintering of nano-sized ceramic powders was introduced by the commercial finite element code ***. The powder plastic model and the thermo-mechanical coupled quadrilateral element were developed and adopted in the simulation. The mechanical and thermal properties of the nano-sized alumina based powders were *** addition, the experimental research and numerical simulation of the sintering process of different initial densities were carried out. The stress state in sintering of green compacts with different initial densities was analyzed by the densification *** reason for the density fluctuations of as-sintered ceramic bulks was found out.

关键词： Sintering, Finite element method, Green compacts, Stress

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COORDINATING PRODUCTION AND RECYCLING DECISIONS WITH STOCHASTIC DEMAND AND RETUR

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Journal of Systems Science and Systems Engineering 2010年第4期19卷 385-407页

作者： Jianmai SHI guoqing zhang Jichang SHA Saman Hassanzadeh AMIN School of Information System and Management National University of Defense Technology Changsha Hunan China Department of Industrial and Manufacturing Systems Engineering University of Windsor Windsor Ontario Canada

In this paper, the joint production and recycling problem is investigated for a hybrid manufacturing and remanufacturing system where brand-new products are produced in the manufacturing plant and recycled products are remanufactured into as-new products in the remanufacturing facility. Both the brand-new products and remanufactured products are used to satisfy customer demands. Returns of used products that are recycled from customers are assumed to be stochastic and nonlinearly price-dependent. A mathematical model is proposed to maximize the overall profit of the system through simultaneously optimizing the production and recycling decisions, subject to two capacity constraints ？ the manufacturing capacity and the remanufacturing capacity. Based on Lagrangian relaxation method, subgradient algorithm and heuristic algorithm, a solution approach is developed to solve the problem. A representative example is presented to illustrate the system, and managerial analysis indicates that the uncertainties in demand and return have much influence on the production and recycling policy. In addition, twenty randomly produced examples are solved, and computational results show that the solution approach can obtain very good solutions for all examples in reasonable time.

关键词： Closed loop supply chain uncertain demand uncertain return reverse logistics Lagrangian relaxation

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金属板+TPO卷材双道防水在潇河国际会展中心项目中的应用

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中国建筑防水 2024年第3期 35-38页

作者：张国庆刘宝辉森特士兴集团股份有限公司北京100176

山西太原潇河国际会展中心中间组团金属屋面工程为复杂双曲结构,采用直立锁边镀铝锌PVDF钢屋面防水板+TPO防水卷材双道防水设计思路,在实现金属屋面系统防水等功能的同时,也保证了屋面双曲造型的完美呈现。本文重点介绍了该项目的屋面... 详细信息

山西太原潇河国际会展中心中间组团金属屋面工程为复杂双曲结构,采用直立锁边镀铝锌PVDF钢屋面防水板+TPO防水卷材双道防水设计思路,在实现金属屋面系统防水等功能的同时,也保证了屋面双曲造型的完美呈现。本文重点介绍了该项目的屋面系统构造设计、屋面板选型、屋面排水深化设计、抗风揭等性能试验结果,阐述了提高金属屋面系统可靠性的各种设计措施。

关键词：会展中心双曲结构金属屋面 66H型直立咬合钢板 TPO防水卷材双道防水抗风揭

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Temporal Dynamics and Performance Association of the Tetrasphaera-Enriched Microbiome for Enhanced Biological Phosphorus Removal

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Engineering 2023年第10期29卷 168-178页

作者： Hui Wang Yubo Wang guoqing zhang Ze Zhao Feng Ju College of Environmental and Resource Sciences Zhejiang UniversityHangzhou 310012China Key Laboratory of Coastal Environment and Resources of Zhejiang Province School of EngineeringWestlake UniversityHangzhou 310024China Institute of Advanced Technology Westlake Institute for Advanced StudyHangzhou 310024China Center of Synthetic Biology and Integrated Bioengineering School of EngineeringWestlake UniversityHangzhou 310024China Research Center for Industries of the Future Westlake UniversityHangzhou 310030China

Tetrasphaera have been recently identified based on the 16S ribosomal RNA(rRNA)gene as among the most abundant polyphosphate-accumulating organisms(PAOs)in global full-scale wastewater treatment plants(WWTPs)with enhanced biological phosphorus removal(EBPR).However,it is unclear how Tetrasphaera PAOs are selectively enriched in the context of the EBPR *** this study,an EBPR microbiome enriched with Tetrasphaera(accounting for 40%of 16S sequences on day 113)was built using a top-down design approach featuring multicarbon sources and a low dosage of *** microbiome showed enhanced nutrient removal(phosphorus removal~85%and nitrogen removal~80%)and increased phosphorus recovery(up to 23.2 times)compared with the seeding activated sludge from a local full-scale *** supply of 1 mg·L^(-1)allylthiourea promoted the coselection of Tetrasphaera PAOs and Microlunatus PAOs and sharply reduced the relative abundance of both ammonia oxidizer Nitrosomonas and putative competitors Brevundimonas and Paracoccus,facilitating the establishment of the EBPR *** on 16S rRNA gene analysis,a putative novel PAO species,EBPR-ASV0001,was identified with Tetrasphaera japonica as its closest *** study provides new knowledge on the establishment of a Tetrasphaera-enriched microbiome facilitated by allylthiourea,which can be further exploited to guide future process upgrading and optimization to achieve and/or enhance simultaneous biological phosphorus and nitrogen removal from high-strength wastewater.

关键词： Enhanced biological phosphorus removal(EBPR) Polyphosphate-accumulating organisms(PAOs) Tetrasphaera Microbiome Phosphorus recovery

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