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Boundary Reducible Handle Additions on Simple 3-Manifolds

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Acta Mathematica Sinica,English Series 2009年第2期25卷 235-244页

作者： Yan Nan LI rui feng qiu Ming Xing ZHANG Department of Applied Mathematics Dalian University of Technology Dalian 116023 P. R. China

Let M be a simple manifold, and F be a component of δM of genus two. For a slope γ on F, we denote by M（γ） the manifold obtained by attaching a 2-handle to M along a regular neighborhood of γon F. In this paper,... 详细信息

关键词： δ-reducible Scharlemann cycle simple manifold

Essential Closed Surfaces in a Class of Surface Sum of I-Bundle of Closed Surfaces

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Journal of Mathematical Research and Exposition 2011年第5期31卷 814-818页

作者： Shu Xin WANG rui feng qiu School of Mathematical Sciences Dalian University of Technology Liaoning 116024 P. R. China

In this paper, we will characterize all types of essential closed surfaces in a class of surface sum ofI-bundle of closed surfaces, and give an application of the classificatioa in the surface sum of two 3-manifolds.

关键词： essential surface surface sum length of thin position.

元·汾渭裂谷文章多——漫步地震五千年(12)

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地震科学进展 2025年第1期55卷 43-62页

作者：冯锐中国地震台网中心北京100045

元朝的山西洪洞于1303年发生8级地震,揭示了汾渭裂谷系在构造和运动上的一系列特殊性。该区地震活动具有准周期性、南移北跳和强震复发的特点。分析了汾渭裂谷的形成、雁行断裂构造、构造应力场和深部高温体的环境背景。为深入认识地球... 详细信息

元朝的山西洪洞于1303年发生8级地震,揭示了汾渭裂谷系在构造和运动上的一系列特殊性。该区地震活动具有准周期性、南移北跳和强震复发的特点。分析了汾渭裂谷的形成、雁行断裂构造、构造应力场和深部高温体的环境背景。为深入认识地球动力学过程,需要扩展眼光,介绍了对地壳块体旋转问题的研究,涉及到鄂尔多斯块体旋转、亚洲中部大区域的地块旋转、汾渭裂谷和贝加尔裂谷的对比、地幔密度分布、喜马拉雅构造结和全球非对称等基本问题。

关键词：汾渭裂谷地壳块体的旋转雁行断裂地幔

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Self-nitrogen-doped porous biochar derived from kapok (Ceiba insignis) fibers： Effect of pyrolysis temperature and high electrochemical performance

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Journal of Materials Science & Technology 2018年第10期34卷 1959-1968页

作者： Jun-rui Wang feng Wan qiu-feng Lu Fei Chen Qilang Lin College of Materials Science and Engineering Fuzhou University Fuzhou 350116 China Key Laboratory of Eco-materials Advanced Technology (Fuzhou University) Fujian Province University Fuzhou 350116 China

Self-nitrogen-doped porous biochar derived from kapok fibers possesses unique structure and excel- lent electrochemical performance. In this study, one-step pyrolysis method was introduced to prepare porous biochar from kapok fibers, and effect of pyrolysis temperature on structure and electrochemical performance of the porous biochar was investigated. It was found that pyrolysis temperature played an important role in determining microstructure of the biochar. At the pyrolysis temperature of 750 ℃, the as-prepared biochar （CKF-750） represented a largest specific surface area of 1125.7 m^2 g^-1 and pore vol- ume of 0.7130 m^3 g^-1, and hence brings CKF-750 a highest specific capacitance of 283 F g^-1 at a current density of I A g^-1 in a 6 mol L^-1 KOH electrolyte. Furthermore, the cycle stability of CKF-750 was wonderful, and the specific capacitance retained almost constant after 10000 cycles. Therefore, the pyrolysis tem- perature of 750 ℃ is optimal for the preparation of porous hiochar as an outstanding electrode material for supercapacitor.

关键词： Kapok fiber Porous biochar Self-nitrogen-doped One-step pyrolysis Electrochemical performance

Deep Active Learning for Solvability Prediction in Power Systems

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1773-1777页

作者： Yichen Zhang Jianzhe Liu feng qiu Tianqi Hong rui Yao Argonne National Laboratory LemontIL 60439USA IEEE

Traditional methods for solvability region analysis can only have inner approximations with inconclusive conservatism and handle limited types of power flow *** this letter,we propose a deep active learning framework for solvability prediction in power *** with passive learning where the training is performed after all instances are labeled,active learning selects most informative instances to be labeled and therefore significantly reduces the size of the labeled dataset for *** the active learning framework,the acquisition functions,which correspond to different sampling strategies,are defined in terms of the on-the-fly posterior probability from the ***,the IEEE 39-bus system is employed to validate the proposed framework,where a two-dimensional case is illustrated to visualize the effectiveness of the sampling method followed by the high-dimensional numerical ***,the Northeast Power Coordinating Council(NPCC)140-bus system is used to validate the performance on large-scale power systems.

关键词： Active learning deep learning power flow solvability power flow equation

Constructing Pr-doped CoOOH catalytic sites for efficient electrooxidation of 5-hydroxymethylfurfural

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Journal of Energy Chemistry 2025年第1期 234-244页

作者： Botao Fan Hao Zhang Bang Gu feng qiu qiue Cao Wenhao Fang School of Chemical Science and Technology Yunnan University National Center for International Research on Photoelectric and Energy Materials School of Materials and Energy Yunnan University

Electrocatalytic conversion of renewable biomass is emerging as a promising route for sustainable chemical production;hence it urgently calls for developing efficient electrocatalysts with low potentials and high current ***,a Pr-doped Co（OH）2hexagonal sheet （Pr/Co=1/9,in mole） is synthesized by electrodeposition as highly performant catalyst for 5-hydroxymethylfurfural （HMF） oxidation reaction（HMFOR） to produce 2,5-furandicarboxylic acid （FDCA）.This novel and low-cost catalyst possesses a rather low onset potential of 1.05 V （***） and requires only 1.10 V （***） to reach a current density of 10 mA cm-2for HMFOR,significantly outperforming Co（OH）2benchmark (i.e.,210 mV higher to reach10 m A cm-2).The origin of Pr promotion effect as well as the evolution of CoOOH catalytic sites and HMFOR process has been deeply elucidated by physical characterizations,kinetic experiments,in situ electrochemical techniques,and theoretical *** unique Pr-ameliorated CoOOH active centers enable 100%conversion of HMF,99.6%selectivity of FDCA,and 99.7%Faraday efficiency,with a superior cycling durability toward *** can be one of the most outstanding results for Co-based HMFOR catalysts to date in the *** this work can help open up new horizons for constructing novel and efficient Co-based electrocatalysts by the utilization of lanthanide elements.

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黑磷/黑砷异质结纳米器件热电性质应力调控研究

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原子与分子物理学报 2025年第1期42卷 69-74页

作者：戎杙邱乙峰张蓓新疆大学物理科学与技术学院乌鲁木齐830046

探索新型高性能低维热电纳米材料已成为国家重大发展策略.论文采用密度泛函理论结合非平衡态格林函数方法研究了由黑磷、黑砷纳米带构建异质结构在2%、4%、6%和8%四种拉伸应变作用下热电性能调控机理.研究结果表明,6%拉伸应变较其他情形... 详细信息

探索新型高性能低维热电纳米材料已成为国家重大发展策略.论文采用密度泛函理论结合非平衡态格林函数方法研究了由黑磷、黑砷纳米带构建异质结构在2%、4%、6%和8%四种拉伸应变作用下热电性能调控机理.研究结果表明,6%拉伸应变较其他情形,能够更有效抑制声子输运行为;与此同时,拉伸应变对于器件的电子输运的调控效果并不明显.在费米能附近,黑磷/黑砷异质结纳米器件在6%拉伸应变调控下热电优值达到最大值2.31.

关键词：黑磷黑砷异质结应力热电性质

基于石墨烯电极TCNQ分子结热/电输运性质理论研究

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原子与分子物理学报 2025年第3期42卷 135-140页

作者：刘仪伟邱乙峰张蓓新疆大学物理科学与技术学院乌鲁木齐830046

本文采用密度泛函理论和非格林平衡函数,对基于石墨烯电极的7,7,8,8-四氰基苯醌二甲烷(Tetracyanoquinodimethane,TCNQ)分子结热/电输运性质进行系统研究.研究结果表明:随着中心TCNQ分子个数的增加,声子透射系数明显降低,即声子透射行... 详细信息

本文采用密度泛函理论和非格林平衡函数,对基于石墨烯电极的7,7,8,8-四氰基苯醌二甲烷(Tetracyanoquinodimethane,TCNQ)分子结热/电输运性质进行系统研究.研究结果表明:随着中心TCNQ分子个数的增加,声子透射系数明显降低,即声子透射行为受到极大抑制.与此同时,电子透射系数也有一定程度的减小.在热/电参数的协同作用下,伴随分子数量的增加分子结热电转换性能呈上升趋势,1TCNQ热电优值(ZT)为0.016,而2TCNQ则上升了1个数量级,ZT值达到0.11.最后,我们对分子结依赖于分子结构个数的自旋输运性质进行研究,发现TCNQ分子结具有显著的自旋过滤效应,其过滤能力随着TCNQ分子数量的增加而增加.该工作可为实验制备分子热电器件提供理论依据和数据支持.

关键词：锯齿状石墨烯纳米带 TCNQ分子自旋输运性质自旋过滤效应

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Influence of Processing Conditions on Microstructure and Mechanical Properties of Large Thin-Wall Centrifugal Ti–6Al–4V Casting

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Journal of Materials Science & Technology 2016年第4期32卷 362-371页

作者： Xin feng Jianke qiu Yingjie Ma Jiafeng Lei Yuyou Cui Xinhua Wu rui Yang Institute of Metal Research Chinese Academy of Sciences Department of Materials Engineering Monash University

In this work, the effects of mould pre-heating temperatures and hot isostatic pressing （HIPping） process on the microstructural characteristics and mechanical properties, including static tensile and damage- tolerance properties of large thin-wall cylindrical Ti-6Al-4V casting, have been studied. The experimental results show that with the increasing mould pre-heating temperature from 673 to 873 K, the casting mi- crostructures change from a mixture of Widmanstatten and colony microstructure to a primary colony. The centre of the thick wall section has relatively coarse microstructure than the edge and thin section. Lower mould pre-heating temperature brings about more porosities. HIPping process, which not only reduces the casting pores effectively but also increases the prior β grain boundary cohesion and coars- ens the microstructure, is essential to improving the ductility of the casting. Due to the oxygen contamination and finer microstructure on the surface, micro-hardness profiles on the cross section present a decreas- ing tendency from the surface to inner. The thickness of the reaction layers for the different mould pre-heating temperatures is nearly the same （-450 μm）. On the whole, the tensile strength and micro- hardness decrease with increasing mould pre-heating temperature from 673 to 873 K. However, the fracture toughness and fatigue crack growth resistance of the castings increase with increasing mould pre- heating temperature.

关键词： Ti-6Al-4V alloyCentrifugal investment castingHot isostatic pressingCasting microstructureTensile propertiesDamage-tolerance properties