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Strain gradient induced grain refinement far below the size limit in a low carbon hypoeutectoid steel(0.19 wt%C)via pipe inner surface grinding treatment

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Journal of Materials Science & Technology 2021年第19期78卷 155-169页

作者： Wenqiang li Yiming Zhao Ning liu changji li Ruiming Ren Dayong Cai Hongwang Zhang National Engineering Research Center for Equipment and Technology of Cold Strip Rolling College of Mechanical EngineeringYanshan UniversityQinhuangdao 066004China National Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China liren College of Yanshan University Yanshan UniversityQinhuangdao 066004China School of Materials Science&Engineering Dalian Jiaotong UniversityDalian 116028China Qinhuangdao Vocational and Technical College Qinhuangdao 066100China

A low carbon hypoeutectoid steel(0.19 wt%C)with proeutectoid ferrite and pearlite dual-components was subjected to surface plastic deformation via pipe inner surface grinding(PISG)at room *** deformation microstructures for each component were systematically characterized along depth,and the patterns of structural evolution toward nanometer regime as well as the governing parameters were *** ferrite grains were refined down to 17 nm,and the pattern covering a length scale of 4–5 orders of magnitude from micron-to nanometer-scale follows:formation of cellular dislocation structure(CDS),elongated dislocation structure(EDS),ultrafine lamellar structure(UFL)and finally the nanolaminated structure(NL).The pearlite experiences the deformation and refinement,and finally the transforming the ultrafine pearlite(UFP)into nanolaminated pearlite(NLP)with the ferrite lamellae as thin as 20 *** for both UFL(UFP)and NL(NLP)can be realized via forming novel extended boundaries within ferrite lamellae.A critical lattice curvature of~2.8°is required for forming such extended boundary,corresponding to a minimum strain gradient of 0.25μm^(-1)for a 100 nm-thick *** below size limit(expressed by lamellar thickness d_Tin nm)is correlated with the strain gradient(χ,inμm^(-1))by:d_T=12.5/*** contributions from strain gradient caused by PISG processing and material heterogeneity were discussed.

关键词： Strain gradient Grain refinement Size limit Low carbon hypoeutectoid steel Pipe inner surface grinding

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中国戏曲文学阐释视角论略

文学遗产 2022年第5期 4-18页

作者：李昌集江苏师范大学文学院

今天面向的中国古代完型戏剧,直接对象是历代文字剧本的“戏曲文学”。中国戏曲的写意化表演,决定了戏曲文学的写意特质,是戏曲文学阐释框架的基础和各种阐释视角的聚焦点。戏曲文学阐释的多元视角,基点是文学本体的阐释,其中有三个重... 详细信息

今天面向的中国古代完型戏剧,直接对象是历代文字剧本的“戏曲文学”。中国戏曲的写意化表演,决定了戏曲文学的写意特质,是戏曲文学阐释框架的基础和各种阐释视角的聚焦点。戏曲文学阐释的多元视角,基点是文学本体的阐释,其中有三个重要的阐释视角:一是戏曲文学的叙述构架,在大众娱乐文化需求和文人自娱的牵动下,文人戏曲写作将大众和文人的传奇意识与诗性意识,交织为戏曲文学特有的叙述模式;二是雅俗文化交构的戏剧故事,生活逻辑与情感愿望的冲突与聚合,表达了大众的普遍人生体验和情感愿望;三是戏曲文学的人学主题,作为一种“爱情专类文学”,爱情悲喜剧和“复合型”人物形象,是中国古代人们共同追求向往的自由之“人”的意象。

关键词：虚拟写意叙述构架生活逻辑情感愿望人学主题

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词之变体机制探论

文学遗产 2023年第1期 56-69页

作者：李昌集江苏师范大学文学院

词体,每一调既有特定程式,又有若干“又一体”。古代词谱对词体形式进行了系统梳理,提出“正体”“变体”概念,但对“变体”为何发生未作解说;今学界深化了词之“乐体”与“文体”关系的研究,但对词之变体机制未作研究。词的“变体”机... 详细信息

词体,每一调既有特定程式,又有若干“又一体”。古代词谱对词体形式进行了系统梳理,提出“正体”“变体”概念,但对“变体”为何发生未作解说;今学界深化了词之“乐体”与“文体”关系的研究,但对词之变体机制未作研究。词的“变体”机制,关涉中国传统歌曲的音乐构成与汉语特有的句法句型。在音乐上,宋词歌谱显示了词调音乐的“变体”习性;在歌曲传唱中,“旧曲新翻”是声歌艺术的常态;在“乐”“词”关系上,汉语歌唱的本根是“以文化乐”,是汉字的不同声调和语句声音织体的音乐化;汉语特有的“流水”句型,是汉语歌曲音乐“变体”的根本支撑。词之变体,是在“乐”“文”双重变体机制中发生的,在古代韵文史上建构了一种新型“弹性文体”范式。

关键词：词乐汉语流水句变体机制弹性文体

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课程与道德的关系:疏离与复归

课程．教材．教法 2022年第2期42卷 42-48页

作者：李长吉李志朋云南师范大学教育学部昆明650500 玉溪师范学院教师教育学院玉溪653100

课程的产生指向公众的道德教化,课程的目的是促进学生的道德成长,课程的过程走向德性之知,这三点确证了课程与道德的本然一体关系。然而,伴随宗教主义课程、知识中心课程和生活取向课程的发展,课程与道德不断走向疏离。宗教主义课程在... 详细信息

课程的产生指向公众的道德教化,课程的目的是促进学生的道德成长,课程的过程走向德性之知,这三点确证了课程与道德的本然一体关系。然而,伴随宗教主义课程、知识中心课程和生活取向课程的发展,课程与道德不断走向疏离。宗教主义课程在极度追求宗教信仰的过程中隐含着对道德理解的异化危机,知识中心课程潜藏着道德探询的弱化风险,生活取向课程因过于注重生活效用而遮蔽了道德。课程向道德的复归,需要在顶层设计上回归课程的道德旨趣,实践运作中彰显道德的多层意蕴,学理支持上把握课程研究的道德路向。

关键词：课程道德宗教主义课程知识中心课程生活取向课程

方程∑_(d|n)SL(d)=φ(n)的可解性

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数学进展 2022年第6期51卷 1005-1010页

作者：李昌吉阿坝师范学院藏汉双语学院汶川四川623002 阿坝师范学院应用数学研究所汶川四川623002

设φ(n)是Euler函数,SL(n)为Smarandache LCM函数.结合φ(n)函数和SL(n)函数的性质,利用初等方法研究了数论函数方程∑_(d|n)SL(d)=φ(n)的可解性,给出了n为奇数时该方程的全部正整数解.

关键词： Smarandache LCM函数 Euler 函数数论函数方程正整数解

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方程Zω(n)=∑d|nS(d)的可解性

安徽大学学报（自然科学版） 2022年第4期46卷 19-23页

作者：李昌吉阿坝师范学院藏汉双语学院四川汶川623002

Zω(n)是伪Smarandache无平方因子函数,S(n)为Smarandache函数.结合Zω(n)函数和S(n)函数的性质,利用初等方法研究了数论函数方程Zω(n)=∑d|nS(d)的可解性,给出当n仅有一个素因子或无平方因子时,方程(1)无正整数解,当n含有平方素因子... 详细信息

Zω(n)是伪Smarandache无平方因子函数,S(n)为Smarandache函数.结合Zω(n)函数和S(n)函数的性质,利用初等方法研究了数论函数方程Zω(n)=∑d|nS(d)的可解性,给出当n仅有一个素因子或无平方因子时,方程(1)无正整数解,当n含有平方素因子且仅有两个素因子时,方程(1)有无穷多组正整数解.

关键词： Smarandache函数伪Smarandache无平方因子函数数论函数方程正整数解

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教师反思的三重境界

课程.教材.教法 2023年第10期43卷 139-147页

作者：李长吉张晓君云南师范大学教育学部昆明650500

教师是反思性存在,教师反思在教师生涯中不可或缺。教师反思有三重境界:教学反思作为职业境界,促进教师的职业发展;实践反思作为事业境界,拓展教师的实践空间;解放反思作为志业境界,促进教师的自我解放。这三重境界共同作用于教师的个... 详细信息

教师是反思性存在,教师反思在教师生涯中不可或缺。教师反思有三重境界:教学反思作为职业境界,促进教师的职业发展;实践反思作为事业境界,拓展教师的实践空间;解放反思作为志业境界,促进教师的自我解放。这三重境界共同作用于教师的个体生命中,做好每个境界的反思工作并突破相应的阻碍,积极努力地向更高境界迈进。这是教师发展的必由之路。

关键词：教师反思教学反思实践反思解放反思

MXenes induce epitaxial growth of size-controlled noble nanometals:A case study for surface enhanced Raman scattering(SERS)

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Journal of Materials Science & Technology 2020年第5期40卷 119-127页

作者： Renfei Cheng Tao Hu Minmin Hu changji li Yan liang Zuohua Wang Hui Zhang Muchan li Hailong Wang Hongxia Lu Yunyi Fu Hongwang Zhang Quan-Hong Yang Xiaohui Wang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China National Engineering Research Center for Equipment and Technology of Cold Strip Rolling College of Mechanical EngineeringYanshan UniversityQinhuangdao 066004China Department of Materials Science and Engineering Monash UniversityClaytonVictoria 3800Australia Institute of Microelectronics Key Laboratory of Microelectronic Devices and CircuitsPeking UniversityBeijing 100871China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China School of Chemical Engineering&Technology Tianjin UniversityTianjin 300072China

Noble nanometals are of significance in both scientific interest and technological applications,which are usually obtained by conventional wet-chemical *** surfactants are always used in the synthesis to prevent unexpected overgrowth and aggregation of noble ***,the surfactants are hard to remove and may interfere with plasmonic and catalytic studies,remaining surfactant-free synthesis of noble nanometals a ***,we report an approach to epitaxial growth of sizecontrolled noble nanometals on *** piloted by density functional theory calculations,along with work function experimental determination,kinetic and spectroscopic studies,epitaxial growth of noble nanometals is initiated via a mechanism that involves an in situ redox *** the redox,MXenes as two-dimensional solid reductants whose work functions are compatible with the reduction potentials of noble metal cations,enable spontaneous donation of electrons from the MXenes to noble metal cations and reduce the cations into nanoscale metallic metals on the outmost surface of *** surfactants nor external reductants are used during the whole synthesis process,which addresses a long-standing interference issue of surfactant and external reductant in the conventional wet-chemical ***,the MXenes induced noble nanometals are ***,noble nanometals firmly anchored on MXenes exhibit excellent performance towards surface enhanced Raman *** developed strategy will promote the nanostructure-controlled synthesis of noble nanometals,offering new opportunities to further improve advanced functional properties towards practical applications.

关键词： Two-dimensional materials MXene In situ redox Noble metal SERS

Preparation and sintering of nanometer W-2 wt.% Y_2O_3 composite powders

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Journal of Rare Earths 2015年第7期33卷 752-757页

作者：李长记刘实熊良银王文涛 Department of Materials for Special Environment Institute of Metal Research Chinese Academy of Sciences

W-2 wt.%Y2O3 composite material with uniform distribution of yttrium element was fabricated through processes of mechanical alloying （MA） and spark plasma sintering （SPS）. The relevant productions were characterized by scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS）, X-ray diffraction （XRD）, and transmission electron microscopy （TEM）. The XRD showed that the W-2 wt.%Y2O3 composite powder, including tungsten matrix and Y2O3 particles, was refined to nanometer sizes during the MA process. The SEM and TEM micrographs showed that the MA produced composite powder presented a lamellar morphology and contained many dislocations and microcracks. The EDS showed that the Y and O elements were uniformly distributed in the W matrix after mechanically alloying for 15 h. The W-2 wt.%Y2O3 composite material with uniform distribution of yttrium was obtained by sintering of the MA produced composite powder.

关键词： W-2 wt.%Y2O3 composite material lamellar nanometer powder uniform distribution of Y MA SPS rare earths