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Counting Rooted 4-regular Unicursal Planar Maps

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Acta Mathematicae Applicatae Sinica 2017年第4期33卷 909-918页

作者： shu-de long Jun-liang CAI department of Mathematics Chongqing University of Arts and Sciences School of Mathematical Sciences Beijing Normal University

A map is 4-regular unicursal if all its vertices are 4-valent except two odd-valent vertices. This paper investigates the number of rooted 4-regular unicursal planar maps and presents some formulae for such maps with ... 详细信息

关键词： unicursal planar map enumerating function functional equation Lagrangian inversion

Mechanism analysis of effect of MgO on reduction swelling behaviour of iron pellets in CO/H_(2)atmosphere based on first-principles calculations

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Journal of Iron and Steel Research International 2025年第1期32卷 73-84页

作者： Hong-ming long Jing-shu An Xing-wang Li Ting Wu Sheng-ping He Jie Lei School of Metallurgical Engineering Anhui University of TechnologyMa’anshan243032AnhuiChina Key Laboratory of Metallurgical Emission Reduction and Resource Comprehensive Utilization(Anhui University of Technology) Ministry of EducationMa’anshan243002AnhuiChina College of Materials Science and Engineering Chongqing UniversityChongqing400044China

To explain the influence mechanism of MgO on the consolidation and reduction characteristics of roasted iron pellets,the properties and structure of pellets were investigated from *** indicated that the MgO addition decreased the reduction swelling index(RSI)and reduction degree of pellets in both CO and H_(2)*** the stepwise reduction process of Fe2O3→Fe3O4→FeO,the reduction behaviour of pellets in CO and H_(2)was similar,while the reduction rate of pellets in H_(2)atmosphere was almost twice as high as that in CO *** the stepwise reduction process of FeO→Fe,the RSI of pellets showed a logarithmic increase in CO atmosphere and a linear decrease in H_(2)*** investigated by first-principles calculations,C and Fe mainly formed chemical bonds,and the CO reduction process released energy,promoting the formation of iron ***,H and Fe produced weak physical adsorption,and the H_(2)reduction process was endothermic,inhibiting the generation of iron *** Mg2+doping in FexO,the nucleation region of iron whiskers expanded in CO reduction process,and the morphology of iron whiskers transformed from“slender”to“stocky,”reducing RSI of the pellets.

关键词： MgO CO atmosphere H_(2)atmosphere Reduction degree Reduction swelling index First-principles calculation

Low-cycle fatigue behavior of K416B Ni-based superalloy at 650 ℃

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Journal of Central South University 2021年第9期28卷 2628-2635页

作者： XIE Jun shu de-long HOU Gui-chen YU Jin-jiang ZHOU Yi-zhou SUN Xiao-feng Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

A study on the low-cycle fatigue(LCF)behavior of K 416 B alloy was conducted at 650℃.According to the results,the LCF behavior of K 416 B alloy at 650℃ is mainly manifested as elastic deformation and the fatigue life of the alloy is determined by the level of material *** tension-compression fatigue occurs,the deformation mechanism of the alloy is reflected in the form of dislocation slip,and the deformation dislocations are bowed out in the matrix by Orowan mechanism,which leads to a dislocation configuration similar to the Frawk-Reed *** the late stage of low-cycle fatigue,the fatigue-induced cracks develop from the alloy *** fatigue test proceeds,it is possible for the cracks to continue development along the regions of eutectic and the bulk M 6 C carbide due to stress concentration,thus causing the alloy to show cleavage fracture.

关键词： K416B alloy low cycle fatigue deformation characteristics fatigue cracks

一种4.5%Re镍基单晶合金在980℃蠕变期间的变形与损伤机制

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材料工程 2017年第1期45卷 93-100页

作者：舒德龙田素贵梁爽张宝帅沈阳工业大学材料科学与工程学院沈阳110870

通过蠕变性能测试和组织形貌观察,研究了一种Re含量为4.5%Re(质量分数,下同)的镍基单晶合金的高温蠕变行为、变形和损伤机制。结果表明,4.5%Re合金在980℃/300MPa的蠕变寿命为169h。蠕变初期,合金中立方γ′相转变为垂直于应力轴的N型... 详细信息

通过蠕变性能测试和组织形貌观察,研究了一种Re含量为4.5%Re(质量分数,下同)的镍基单晶合金的高温蠕变行为、变形和损伤机制。结果表明,4.5%Re合金在980℃/300MPa的蠕变寿命为169h。蠕变初期,合金中立方γ′相转变为垂直于应力轴的N型筏状结构。稳态蠕变期间,合金的变形机制为位错在基体中滑移和攀移越过筏状γ′相。蠕变后期,合金的变形机制为位错在基体中滑移和剪切进入筏状γ′相。由于γ基体通道较窄,位错在基体通道中滑移所需的阻力较大。剪切进入γ′相的超位错可由{111}面交滑移至{100}面,形成K-W锁,从而抑制位错的滑移和交滑移,这是合金具有较好蠕变抗力的主要原因。主/次滑移位错的交替开动,可致使筏状γ′相扭曲,并促使裂纹在筏状γ/γ′两相界面萌生;裂纹沿垂直于应力轴方向扩展,直至断裂,这是合金的蠕变断裂机制。

关键词：镍基单晶合金铼蠕变变形机制 K-W锁

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带根单行平面地图的计数

数学学报（中文版） 2010年第1期53卷 9-16页

作者：龙述德蔡俊亮重庆文理学院数学系重庆402160 北京师范大学数学科学院北京100875

提供了根点为一个奇点的带根单行平面地图以其边数、根点次和非根奇点次为参数的生成函数所满足的一些函数方程,并且导出了这些函数的显式,它们有两个是无和式.

关键词：单行平面地图计数函数 Lagrange反演

一种含4.5%Re/3.0%Ru的单晶镍基合金的高温蠕变行为

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材料工程 2017年第3期45卷 41-46页

作者：舒德龙田素贵吴静张宝帅梁爽沈阳工业大学材料科学与工程学院沈阳110870

通过对含4.5%Re/3.0%Ru单晶镍基合金进行高温蠕变性能测试,并采用扫描电镜(SEM)、透射电镜(TEM)对不同蠕变期间的试样进行组织形貌观察,研究了该合金的高温蠕变行为。结果表明,本实验所选用的单晶合金在高温蠕变期间具有良好的蠕变抗力,... 详细信息

通过对含4.5%Re/3.0%Ru单晶镍基合金进行高温蠕变性能测试,并采用扫描电镜(SEM)、透射电镜(TEM)对不同蠕变期间的试样进行组织形貌观察,研究了该合金的高温蠕变行为。结果表明,本实验所选用的单晶合金在高温蠕变期间具有良好的蠕变抗力,在1040℃/160MPa的蠕变寿命达到725h。高温蠕变初期,合金中γ′相沿垂直于应力轴方向转变成筏状结构,其稳态蠕变期间的变形机制是位错在基体中滑移和攀移越过筏状γ′相。高温蠕变后期,合金的变形机制是位错在基体中滑移和剪切筏状γ′相。位错的交替滑移使筏形γ′相扭曲,并在γ/γ′两相界面发生裂纹的萌生与扩展直至断裂,是合金在高温蠕变后期的断裂机制。

关键词：单晶镍基合金 Re/Ru 高温蠕变性能断裂机制

Gold-catalyzed intermolecular amination of allyl azides with ynamides: Efficient construction of 3-azabicyclo[3.1.0] scaffold

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Chinese Chemical Letters 2025年第2期36卷 384-388页

作者： Chong-Yang Shi Jian-Xing Gong Zhen Li Chao shu long-Wu Ye Qing Sun Bo Zhou Xin-Qi Zhu College of Chemistry and Chemical Engineering Yunnan Normal University Key Laboratory of Chemical Biology of Fujian Province State Key Laboratory of Physical Chemistry of Solid Surfacesand College of Chemistry and Chemical EngineeringXiamen University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciences Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong University

Gold-catalyzed amination reactions based on azides via α-imino gold carbene intermediates have attracted extensive attention in the past decades because this methodology leads to the facile and efficient construction of synthetically useful N-containing molecules, especially valuable N-heterocycles. However,successful examples of intermolecular generation of α-imino gold carbenes by using azides as amination reagents are rarely explored probably due to the weak nucleophilicity of azides. Herein, we disclose an efficient gold-catalyzed intermolecular aminative cyclopropanation of ynamides with the allyl azides, enabling flexible synthesis of a wide range of valuable 3-azabicyclo[3.1.0]hex–2-ene derivatives in good to excellent yields with excellent diastereoselectivities. Importantly, this protocol represents the first use of allyl azide as an efficient amination reagent in gold-catalyzed alkyne amination reactions.

关键词： Alkynes Amination Azides Gold Heterocycles

Predictor−corrector inverse design scheme for property−composition prediction of amorphous alloys

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中国有色金属学报 2025年第1期35卷 169-183页

作者： Tao long Zhi-lin long Bo PANG School of Mechanical Engineering and Mechanics Xiangtan UniversityXiangtan 411105China School of Civil Engineering Xiangtan UniversityXiangtan 411105China

In order to develop a generic framework capable of designing novel amorphous alloys with selected target properties,a predictor−corrector inverse design scheme(PCIDS)consisting of a predictor module and a corrector module was presented.A high-precision forward prediction model based on deep neural networks was developed to implement these two *** utmost importance,domain knowledge-guided inverse design networks(DKIDNs)and regular inverse design networks(RIDNs)were also *** forward prediction model possesses a coefficient of determination(R^(2))of 0.990 for the shear modulus and 0.986 for the bulk modulus on the testing ***,the DKIDNs model exhibits superior performance compared to the RIDNs *** is finally demonstrated that PCIDS can efficiently predict amorphous alloy compositions with the required target properties.

关键词： amorphous alloys machine learning deep neural networks inverse design elastic modulus

热处理对4.5%Re单晶镍基合金高温蠕变行为的影响

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中国有色金属学报 2015年第6期25卷 1480-1489页

作者：舒德龙田素贵吴静李秋阳蒋崇亮沈阳工业大学材料科学与工程学院沈阳110870

通过对一种4.5%Re(质量分数)镍基单晶合金进行不同工艺热处理、蠕变性能测试及组织形貌观察,研究了固溶时间对该合金组织结构与高温蠕变行为的影响。结果表明:铸态合金中各元素存在较大的成分偏析,经高温长时间固溶及时效处理后,合金中... 详细信息

通过对一种4.5%Re(质量分数)镍基单晶合金进行不同工艺热处理、蠕变性能测试及组织形貌观察,研究了固溶时间对该合金组织结构与高温蠕变行为的影响。结果表明:铸态合金中各元素存在较大的成分偏析,经高温长时间固溶及时效处理后,合金中各元素在枝晶间/臂的偏析程度明显降低;将固溶时间由10 h延长至24 h后,合金在1100℃、137 MPa的蠕变寿命由101 h提高至164 h;其中,10 h固溶处理合金中仍存在较大程度的元素偏析,并且在蠕变期间,析出针状TCP相。合金在高温蠕变期间的变形机制是位错在基体中滑移和剪切筏状γ′相;蠕变后期,大量位错剪切筏状γ′相,致使近断口区域的筏状γ′相扭曲,在筏状γ/γ′两相界面发生裂纹的萌生,并沿垂直于应力轴方向扩展,直至发生蠕变断裂。这是合金的高温蠕变断裂机制。

关键词：单晶镍基合金 Re TCP相元素偏析蠕变