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Upper Bounds on the Multicolor Ramsey Numbers r_(k)(C_(4))

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Acta mathematicae Applicatae Sinica 2025年第1期41卷 286-294页

作者： Tian-yu LI qi-zhong LIN Center for Discrete mathematics Fuzhou UniversityFuzhou 350108China

The multicolor Ramsey number r_(k)(C_(4))is the smallest integer N such that any k-edge coloring of KN contains a monochromatic C_(4).The current best upper bound of r_(k)(C_(4))was obtained by Chung(1974)and independently by Irving(1974),i.e.,r_(k)(C_(4))≤k^(2)+k+1 for all k≥*** is no progress on the upper bound since *** this paper,we improve the upper bound of r_(k)(C_(4))by showing that r_(k)(C_(4))≤k^(2)+k-1 for even k≥*** improvement is based on the upper bound of the Turan number ex(n,C4),in which we mainly use the double counting method and many novel ideas from Firke,Kosek,Nash,and Williford[***,Ser.B 103(2013),327-336].

关键词： Multicolor Ramsey number Turan number 4-cycle

Simulation and Analysis of Microstructure Evolution of IN718 in Rotary Forgings by FEM

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Journal of Shanghai Jiaotong university(Science) 2008年第6期13卷 721-726页

作者：于忠奇马秋林忠钦 School of Mechanical Engineering Shanghai Jiaotong UniversityShanghai 200240China

A numerical analysis was performed to study the influence of process parameters on the microstructure evolution of IN718 alloy in rotary forging using the finite element method （FEM）. For this purpose, a constitutive equation considering the effects of strain hardening and dynamic softening of IN718 alloy was built. The constitutive equation and microstructure models were implemented into the finite element code to investigate the microstructure evolution during rotary forging subject to large deformations. The simulations were carried out in the ratio of initial height to diameter range 0.2-0.8, the angle of the rocker 3°-7° and the relative feed per revolution range 0.01-0.1 r^-1. The research results revealed the deformation mechanism and the correlation of process parameters with the grain size evolution of IN718 alloy during rotary forging. These provide evidence for the selection of rotary forging parameters.

关键词： rotary forging finite element method (FEM) microstructure evolution deformation mechanism IN718 alloy

A FACILE METHOL FOR THE DEBROMINATION OF BROMOCARBONYL COMPOUNDS WITH DIBUTYL TELLURIDE

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Chinese Chemical Letters 1990年第2期1卷 133-134页

作者： qi zhong Feng ma Chang qing LIU Jian Guo SHAO Chemistry Department,Yangzhou Teachers College,Yangzhou 225002

(?)-bromocarbonyl compounds can be debrominated with dibutyl telluride in the presence of triethylamine in high yields.

关键词： A FACILE METHOL FOR THE DEBROMINATION OF BROMOCARBONYL COMPOUNDS WITH DIBUTYL TELLURIDE

Photolithographic Microfabrication of Microbatteries for On-Chip Energy Storage

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Nano-Micro Letters 2025年第5期17卷 117-144页

作者： Yuan ma Sen Wang zhong-Shuai Wu State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023People’s Republic of China School of Transportation Engineering Dalian Jiaotong UniversityDalian 116028People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalian 116023People’s Republic of China

Microbatteries(MBs)are crucial to power miniaturized devices for the Internet of *** the evolutionary journey of MBs,fabrication technology emerges as the cornerstone,guiding the intricacies of their configuration designs,ensuring precision,and facilitating scalability for mass *** stands out as an ideal technology,leveraging its unparalleled resolution,exceptional design flexibility,and entrenched position within the mature semiconductor ***,comprehensive reviews on its application in MB development remain *** review aims to bridge that gap by thoroughly assessing the recent status and promising prospects of photolithographic microfabrication for ***,we delve into the fundamental principles and step-by-step procedures of photolithography,offering a nuanced understanding of its operational mechanisms and the criteria for photoresist ***,we highlighted the specific roles of photolithography in the fabrication of MBs,including its utilization as a template for creating miniaturized micropatterns,a protective layer during the etching process,a mold for soft lithography,a constituent of MB active component,and a sacrificial layer in the construction of micro-Swiss-roll ***,the review concludes with a summary of the key challenges and future perspectives of MBs fabricated by photolithography,providing comprehensive insights and sparking research inspiration in this field.

关键词： Microbatteries Photolithography Internet of Things Micropatterns On-chip energy storage

A FACILE SYNTHESIS OF HETEROCYCLE SUBSTITUTED CHALCONE AND 5-NITROFURANYL OLEFIN DERIVATIVES

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Chinese Chemical Letters 1991年第2期2卷 107-110页

作者： qi zhong Feng ma Chang qing LIU Jian Guo SHAO Rong Jian LU Chemistry Department,Yangzhou Teachers College,Yangzhou,225002

Reaction of heterocycle substituted telluronium salts with aroma- tic aldehydes under mild conditions gave corresponding *** the presence of dibutyl telluride,2-bromomethyl-5-nitrofuran condensed easily with aromatic ... 详细信息

关键词： CHC A FACILE SYNTHESIS OF HETEROCYCLE SUBSTITUTED CHALCONE AND 5-NITROFURANYL OLEFIN DERIVATIVES 孙介

Enantioselective reductive conjugate alkenylation ofα,β-enones with keto alkenyl acetates by nickel catalysis

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Science China Chemistry 2025年第1期68卷 157-162页

作者： Rong-De He Yun-Lei Luo qiu-Quan Pan qi-Wei Yao Xing-zhong Shu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis,yet their asymmetric variant remains ***,asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–*** manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl *** method facilitates the enantioselective addition of keto alkenyl groups toα,β-enones,resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access *** use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

关键词： nickel alkenylation asymmetric cross-coupling alkenes

Effect of rolling schedules on ridging resistance of ultra-thin ferritic stainless steel foil

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Journal of Iron and Steel Research International 2025年第1期32卷 198-214页

作者： Jing-wei Zhao qing-zhong Xie Li-nan ma Cun-long Zhou Zheng-yi Jiang Xi Liao Xiao-guang ma College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment Ministry of EducationTaiyuan030024ShanxiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment Ministry of Science and TechnologyTaiyuan030024ShanxiChina School of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuan 030024ShanxiChina School of Mechanical MaterialsBiomedical and Mechatronic EngineeringUniversity of WollongongWollongongNSW2522Australia Shanxi Taigang Stainless Steel Precision Strip Co. Ltd.Taiyuan 030006ShanxiChina

The effect of rolling schedules on the ridging resistance of ultra-thin ferritic stainless steel(FSS)430 foil was evaluated by studying the microstructure and *** results show that specimens processed with three-pass cold rolling under the reductions of 40%,40%and 31%,respectively,exhibit improved ridging resistance owing to the microstructural refinement and the texture structure optimization.A nearly 40%reduction of ridging height can be achieved using the proposed rolling schedule compared to the other two rolling *** addition,the effect of annealing temperature after cold rolling on the ridging resistance of FSS 430 foil is also found to be crucial,and an optimal annealing temperature of 900℃ is obtained for FSS 430 foil with high ridging ***,the improvement in the ridging resistance of FSS 430 foil can be attributed to the reduction in the fraction of{001}and{114}components by optimization of the rolling and annealing processes.

关键词： Ferritic stainless steel foil Ridging Cold rolling Annealing Microstructure Texture

Electronic modulation induced by coupling RuO2 with electron-donating Co3O4 for high-active and long-life rechargeable Zn-air batteries

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Journal of Energy Chemistry 2025年第2期101卷 99-109页

作者： Xuena ma Zhangxin Xu Mingyang Liu Panzhe qiao qi Li Ruihong Wang Baojiang Jiang Key Laboratory of Functional Inorganic material Chemistry Ministry of Education of the People's Republic of China School of Chemistry and Materials ScienceHeilongjiang University Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences

Electronic-state modulation strategy offers great potential in designing RuO2-based bifunctionalelectrocatalysts for rechargeable Zn-air batteries（ZABs）.Various three-dimensional（3D） transition metal oxides are attempted to couple with RuO2for constructing an appropriate Ru—O—M *** work aims to construct Co3O4-RuO2heterostructures on carbon sheets（Co3O4/RuO2/NCNS） for boosting electronic transfer and *** and theoretical calculations identify the electronic transfer from Co3O4to RuO2that modulates the electronic structure of metal surfaces/***,it leads to the increase in Co3+content,electron-rich state at RuO2surface and electronic accumulation at ***,this electronic-state modulation optimizes the d-band center in Co3O4/RuO2that lowers the reaction barriers and endows interfaces as the biggest contributor to oxygen reduction reaction（ORR） and oxygen evolution reaction（OER） performance,The Co3O4/RuO2/NCNS shows a quite low potential difference of 0.62 V and remarkable durability for ORR/***3O4/RuO2/NCNS-assembled ZABs exhibit an excellent specific capacity of 818.3 ma h g-1and a superior lifespan over 750 h.

关键词： Charge-discharge stability Co3O4-RuO2 heterostructure Electronic modulation Reaction energy barrier Zn-air battery

STATIC AND SPHERICALLY SYMMETRIC DYON SOLUTIONS IN SU(N) GAUGE THEORY

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Chinese Science Bulletin 1983年第3期28卷 328-332页

作者：马中骐 Institute of High Energy Physics Academia Sinica Beijing few years ago 'tHooft and Polyakov found out a finite-mass regular monopole solution in SU (2) gauge field. They discussed the interaction system of SU (2) (SO(3)) gauge field and Higgs field in adjoint representation assumed as an ansatz

A few years ago, ’tHooft and Polyakov found out a finite-mass regular monopole solution in SU (2) gauge field. They discussed the interaction system of SU (2) (SO(3)) gauge field and Higgs field in adjoint representa... 详细信息

关键词： gauge assumed adjoint infinity ordinary string 一诚 Olive latter inserted