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Influence of loading path on formability of 304 stainless steel tubes

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Science China(Technological Sciences) 2009年第8期52卷 2263-2268页

作者： ZHANG ShiHong YUAN anying WANG Bin ZHANG HaiQu WANG ZhongTang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Shenyang University Shenyang 110044China Shenyang Ligong University Shenyang 10168China

The loading path affects the metal formability remarkably in tube hydroforming, and it is also one of the research focuses. Recently, some scholars abroad proposed a new fluctuant hydraulic loading method, which can improve the formability of tubes in hydroforming. Related studies have shown that this new loading method can improve the tube formability, the distribution of deformation is more uniform and this is useful for avoiding excessive local thinning. In this paper, tube hydroforming experiments without axial feeding were carried out; the influences of the loading methods on formability of stainless steel tubes were studied. Through the comparison of the experimental results under the condition of monotonous increase loading and fluctuation hydraulic loading, the outside diameter distribution, the thickness distribution and the crack expansion forms of deformation zone all fully prove that the uniformity of the distribution of tube deformation and formability have been increased significantly under the condition of fluctuation loading without axial feeding, the reasons should be distinguished from the fluctuation hydroforming with axial feeding. In order to study the forming mechanism, uniaxial tensile test of tubes similar to fluctuation loading deformation is designed in this paper, namely intermittent tensile test. It is found that intermittent uniaxial stretch can improve the tube elongation at fracture by about 40% and the deformation distribution is more uniform than that through uniaxial tensile test of the stainless steel tube. In the process of intermittent tensile tests, changes of metal microstructures brought by the loading and unloading processes are the main reasons that improve the formability of the tubes.

关键词： loading path formability tube stainless steel

Application and prospects of 3D printing in physical experiments of rock mass mechanics and engineering:materials,methodologies and models

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International Journal of Coal Science & Technology 2023年第1期10卷 1-17页

作者： Qingjia Niu Lishuai Jiang Chunang Li Yang Zhao Qingbiao Wang anying Yuan State Key Laboratory of Mining Disaster Preventionand Control Shandong University of Scienceand TechnologyQingdao 266590China State Key Laboratory of Mining Response and DisasterPrevention and Control in Deep Coal Mines AnhuiUniversity of Science and TechnologyHuainan 232001China College of Resources Shandong University of Scienceand TechnologyTaian 271019China

The existence of joints or other kinds of discontinuities has a dramatic efect on the stability of rock excavations and *** a result,a great challenge in rock mass mechanics testing is to prepare rock or rock-like samples with *** recent years,3D printing technology has become a promising tool in the feld of rock mass mechanics and *** study frst reviews and discusses the research status of traditional test methods in rock mass mechanics tests of making rock samples with ***,based on the comprehensive analysis of previous research,the application of 3D printing technology in rock mass mechanics is expounded from the following three *** frst is the printing *** there are many materials for 3D printing,it has been found that 3D printing materials that can be used for rock mass mechanics research are very *** research,we summarize and evaluate printing material that can be used for rock mass mechanics *** second is the printing methodology,which mainly introduces the current application forms of 3D printing technology in rock mass *** includes printed precise casting molds and one-time printed *** last one is the printing model,which includes small-scale samples for mechanical tests and large-scale physical ***,the benefts and drawbacks of using 3D printing samples in mechanical tests and the validity of their simulation of real rock are *** with traditional rock samples collected in nature or synthetic rock-like samples,the samples made by 3D printing technology have unique advantages,such as higher test repeatability,visualization of rock internal structure and stress *** is thus great potential for the use of 3D printing in the feld of rock mass ***,3D printing materials also have shortcomings,such as insufcient material strength and accuracy at this ***,the application prospect of 3D printing technology in

关键词： 3D printing Rock mass mechanics Prefabricated cracks Rock-like material Fractured rock mass

Pre-warning information dissemination models of different media under emergencies

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Chinese Physics B 2020年第9期29卷 343-352页

作者： anying Chen Haoran Zhu Xiaoyong Ni Guofeng Su Institute of Public Safety Research Tsinghua UniversityBeijing 100084China Beijing Key Laboratory of City Integrated Emergency Response Science Beijing 100084China

Pre-warning plays an important role in emergency handling, especially in urban areas with high population density like Beijing. Knowing the information dissemination mechanisms clearly could help us reduce losses and ensure the safety of human beings during emergencies. In this paper, we propose the models of pre-warning information dissemination via five classical media based on actual pre-warning issue processes, including television, radio, short message service (SMS), electronic screens, and online social networks. The population coverage ability and dissemination efficiency at different issue time of these five issue channels are analyzed by simulation methods, and their advantages and disadvantages are compared by radar graphs. Results show that SMS is the most appropriate way to issue long-term pre-warning for its large population coverage, but it is not suitable for issuing urgent warnings to large population because of the limitation of telecom company's issue ability. TV shows the best performance to combine the dissemination speed and range, and the performance of radio and electronic screens are not as satisfactory as the others. In addition, online social networks might become one of the most promising communication method for its potential in further diffusion. These models and results could help us make pre-warning issue plans and provide guidance for future construction of information diffusion systems, thus reducing injuries, deaths, and other losses under different emergencies.

关键词： information dissemination emergency pre-warning media

Aqueous lubrication and surface microstructures of engineering polymer materials (PEEK and PI) when sliding against Si3N4

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Friction 2017年第4期5卷 414-428页

作者： anying WANG Shuai YAN Bin LIN Xiaofeng ZHANG Xiaoxue ZHOU Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of Education Tianjin UniversityTianjin 300350China

Polyether-ether-ketone (PEEK) and polyimide (PI) are two kinds of engineering polymer materials widely used as roller bearing cages and rings under extreme environment because of their noise reduction and corrosion resistance *** Si3N4 ceramic is the most common ball bearing *** current engineering applications of ball bearings require aqueous ***,this study presents the aqueous lubrication of tribopairs formed by PEEK and PI material sliding against Si3N4 *** results show that two tribopairs exhibited the similar tribological properties under the dry *** as a lubricant for the PI-Si3N4 tribopair pairs effectively reduces both friction coefficients by 35.5％ and wear rates by 32％.The water absorption of PI induces better tribological properties by changing the tribopair surface *** addition,the dimples appearing on the PI tribopair surface under water generate additional hydrodynamic lubrication and further improve the friction properties of *** PEEK-Si3N4 tribopair shows similar friction coefficients under two kinds of *** wear rates under water are approximately more than two times of that under dry ***,water inhibits the appearance of the crush phenomenon and enhances the carrying capacity of the *** dispersive spectroscopy and X-ray diffraction spectra demonstrate no chemical *** 3D profiler and SEM morphologies illustrate that the transfer film would be formed from the surface of PEEK under water but hindered under dry ***,the PI-Si3N4 tribopair exhibits better properties than PEEK under water and is promising for future applications in the bearing industry.

关键词： PEEK PI aqueous lubrication dry friction tribological properties ceramic bearing

Organic Materials Could Improve the Phytoremediation Efficiency of Soil Potentially Hazardous Metal by Sedum alfredii Hance

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Phyton-International Journal of Experimental Botany 2022年第7期91卷 1529-1542页

作者： Peifan Wang Shengting Rao Jia Fang Yongqiang Lv anying Zhao Zhengqian Ye Weijun Fu State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou311300China Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province Zhejiang A&F UniversityHangzhou311300China

Soil potentially hazardous metal(PHM)is continually attracting public attention worldwide,due to its highly toxic properties and potentially huge damage to human being through food *** is an effective and eco-friendly way in remediation technology.A pot experiment was carried out to investigate the effect of different organic materials(biogas residue(BR),mushroom residue(MR),and bamboo-shoot shell(BS))application on phytoremediation of two PHM-contaminated soils(Fuyang soil as‘heavily-polluted soil’and Wenzhou soil as‘moderately-polluted soil’,respectively)by Sedum alfrecdii *** results indicated:1)for moderately-polluted soil,the 5%BR treatment had the strongest activation to Cu and Zn,for heavily-polluted soil,1%BS treatment had the highest activation effect for Cu,Zn,Pb and Cd.2)the above-ground biomass of Sedum alfredii Hance increased with the addition rate of organic materials.3)for Cd uptake of Sedum alfredii Hance in moderately-polluted soil,only 1%BS treatment had a better accumulation effect,compared to the control,for Zn element,MR treatments were weaker than the control,while other treatments were better than the control,of which 5%BR,1%BS and 5%BS accumulated more Zn element by 39.6%,32.6%and 23.8%,respectively;in heavily-polluted soil,the treatments of 5%BS,1%BR and 5%BR accumulated more Cd than the control by 12.9%,12.8%and 6.2%,respectively,the treatments with organic materials addition promoted Zn accumulation in shoots of Sedum alfredii Hance,and the best treatment was 5%***,an appropriate application rate of BS and BR could improve the remediation efficiency for Zn/Cd contaminated soils by Sedum alfredii Hance.

关键词： Organic material Sedum alfredii Hance potentially hazardous metal polluted soil phytoremediation efficiency

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重庆方言的“倒”字

成都大学学报（社会科学版） 2010年第1期 108-111页

作者：杨岸颖上海财经大学国际文化交流学院上海200083

重庆方言中的"倒"可表示动作行为的进行,也可表示动作状态的持续,也可表示动作的方式和结果,用法很多,是重庆方言中使用频率非常高的一个词。重庆方言的"倒"可和普通话中的"着"字作比较。

关键词：重庆方言倒着

Stimulating the Vitality of Tradition -- Tsinghua＇s Practice in Research and Training of Intangible Cultural Heritage Inheritors

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China & The World Cultural Exchange 2017年第3期83卷 34-35页

作者： Chen anying

In 2015, the Academy of Arts ＆ Design of Tsinghua University became one of the first batch of pilot institutes for＂Research and Training Plan for Inheritors of Intangible Cultural Heritage in China＂ under the Minis... 详细信息

关键词：非物质文化遗产培养传承生命传统设计学院清华大学教育部

Tradition Revival： A Constant Process of Discovery and Creation

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China & The World Cultural Exchange 2017年第6期83卷 26-27页

作者： Chen anying

In the process of tradition revival, everyone should break the limitations of ideas and concepts and adjust our own knowledge structure with diversified and open mind through retracing the local cultural traditions. The inheritors should even more expand their visions, intensify exchanges and collisions, break the current limitations and conduct constant reflection and researches. Only in this way; can they create new peaks.

关键词：文化传统知识结构思想观念多元化

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重新定义艺术

文艺理论研究 2015年第6期35卷 29-35,68页

作者：陈岸瑛清华大学美术学院艺术史论系

本文结合当代艺术哲学对艺术定义的讨论,提出了一种对艺术的新定义。本文认同肯尼克和丹托对于艺术的开放式定义,但认为这一定义忽视了"艺术"这一概念所包含的价值维度。本文认为,艺术(绘画、雕塑等)既是生产,也是文化,就此而言,艺术是... 详细信息

本文结合当代艺术哲学对艺术定义的讨论,提出了一种对艺术的新定义。本文认同肯尼克和丹托对于艺术的开放式定义,但认为这一定义忽视了"艺术"这一概念所包含的价值维度。本文认为,艺术(绘画、雕塑等)既是生产,也是文化,就此而言,艺术是通过某种技艺来创造文化价值的生产。传统美学将艺术定义为:艺术=工艺+审美价值;艺术品=产品+审美价值。而我们则将艺术定义为:艺术=工艺+文化价值﹛A,B,C…Z﹜;艺术品=产品+文化价值﹛A,B,C…Z﹜。与传统美学对艺术的定义相比,这个定义超越了特定文化对艺术的理解,使得不同文化中的"艺术品"有了相互比较的可能,也使得世界艺术史或艺术通史的写作得以可能。

关键词：艺术定义美学艺术史审美价值文化价值