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On the Average Number of Unitary Factors of Finite Abelian Groups (Ⅱ)

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Acta Mathematica Sinica,English Series 2000年第4期16卷 549-554页

作者： wenguang zhai Department of Mathematics, shandong normal university. jinan 250014. P. B. china Department of Mathematics Shandong Normal University Jinan 250014 P. R. China

Let t（G） be the number of unitary factors of finite abelian group G. In this paper we prove T（x）=∑(G≤（）t（G） =main terms+O(x(（1+2k）/（3+4k）for any exponent pair （k, 1/2+2K）. which improves on the exponen... 详细信息

关键词： Unitary factor Finite Abelian group Exponential sum Divisor problem

Enhanced nitrite electroreduction to ammonia via interfacial dual-site adsorption

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Journal of Energy Chemistry 2024年第9期96卷 328-335页

作者： Xiaokang Chen Shengliang zhai Yi Tan Le Su Dong zhai Wei-Qiao Deng Hao Wu Institute of Frontier Chemistry School of Chemistry and Chemical EngineeringShandong UniversityQingdao 266071ShandongChina College of Physics and Information Engineering Shanxi Normal UniversityTaiyuan 030031ShanxiChina Suzhou Research Institute of shandong university Suzhou 215123JiangsuChina

The nitrite(NO_(2)^(−))to ammonia(NH3)electroreduction reaction(NO_(2)^(−)RR)would be impeded by sluggish proton-coupled electron transfer kinetics and competitive hydrogen evolution reaction(HER).A key to improving the NH_(3) selectivity is to facilitate adsorption and activation of NO_(2)^(−),which is generally undesirable in unitary *** this work,an efficient NO_(2)^(−)RR catalyst is constructed by cooperating Pd with In2O3,in which NO_(2)^(−)could adsorb on interfacial dual-site through“Pd–N–O–In”linkage,leading to strengthened NO_(2)^(−)adsorption and easier N=O bond cleavage than that on unitary Pd or ***,the Pd/In_(2)O_(3)composite exhibits moderate H^(*)adsorption,which may facilitate protonation kinetics while inhibiting competitive *** a result,it exhibits a fairly high NH_(3)yield rate of 622.76 mmol h^(−1)g^(−1)cat with a Faradaic efficiency(FE)of 95.72%,good selectivity of 91.96%,and cycling stability towards the NO_(2)^(−)RR,surpassing unitary In_(2)O_(3)and Pd/C ***,computed results indicate that NH_(3)production on Pd/In_(2)O_(3)follows the deoxidation to hydrogenation *** work highlights the significance of H^(*)and NO_(2)^(−)adsorption modulation and N=O activation in NO_(2)^(−)RR electrochemistry by creating synergy between a mediocre catalyst with an appropriate cooperator.

关键词： Dual-site adsorption Nitrite electroreduction Ammonia Pd Hydrogenation

Electronic structure and geometric construction modulation of carbon-based single/dual atom catalysts for electrocatalysis

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Energy Reviews 2024年第3期3卷 76-91页

作者： Shaolong Zhang Jing Huang Li Ma Dong zhai Bin Wei Hengpan Yang Chuanxin He College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen518060PR China Pharmaceutical College Guangxi Medical UniversityNanning530021PR China Key Laboratory of New Electric Functional Materials of Guangxi Colleges and Universities Nanning Normal UniversityNanning530023PR China Institute of Molecular sciences and Engineering Institute of Frontier and Interdisciplinary ScienceShandong UniversityQingdao266237PR China school of Materials Sun Yat-sen UniversityShenzhen518107PR China

Both carbon-based single atom catalysts(SACs)and dual atom catalysts(DACs)have garnered significant attention in the field of electrochemical reactions because of the impressive attributes,including exceptional catalytic activity,selectivity,and *** ability to modulate the electronic structure and geometric construction of active sites within SACs/DACs is paramount for unleashing their complete potential,which in turn can ultimately dictate catalytic behavior with unprecedented *** this review,the recent major developments of the regulation strategies for modulating electronic structure and geometric construction of carbon-based SACs/DACs are *** the SACs,the recently reported modulation methods are categorized into four strategies,including adjusting the density of single atoms,defect engineering,confinement effect and strain *** for the DACs,the five methods contain bonded dual-atom adjustment,non-bonded and bridged dual-atom adjustment,metal and nonmetal dual-atom adjustment,bilayer dual-atom adjustment and homogeneous dual-atom *** recently developed synthetic strategies are comprehensively summarized,especially their electronic structure and geometric configuration are discussed in detail,the different catalytic applications of electrochemical reactions,and their unique catalytic mechanism are ***,the challenges and prospects of SACs/DACs for tailoring their electronic structures and geometric arrangements are further discussed.

关键词： Electronic structure Geometric construction Single atom catalysts Dual atom catalysts Modulation

Diophantine inequalities over Piatetski-Shapiro primes

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Frontiers of Mathematics in china 2021年第3期16卷 749-770页

作者： Jing HUANG wenguang zhai Deyu ZHANG school of Mathematics and Statistics Shandong Normal UniversityJinan250014China Department of Mathematics China University of Mining and TechnologyBeijing100083China

Let c>1 and 0<γ<*** study the solubility of the Diophantine inequality∣p^(c)_(1)+p^(c)_(2)+…+p^(c)_(s)−N∣<(log N)^(−1) in Piatetski-Shapiro primes p_(1),p_(2),…,p_(s) of the form pj=[m^(1/γ)]for some m∈ℕ,and im... 详细信息

关键词： Diophantine inequalities Piatetski-Shapiro primes exponential sums additive problems

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Beatty序列中的除数问题

数学学报（中文版） 2004年第6期47卷 1213-1216页

作者：吕广世翟文广山东大学数学与系统科学学院济南250100 山东师范大学数学科学学院济南250014

本文研究Beatty序列中的除数问题,证明了在Lebesgue测度意义下,对几乎所有的θ≥1,当k≥5时,一致地有Dk(θ;x)=∑n≤x/θdk([nθ])=θ-1Dk(1;x)+O(x4/5+ε).

关键词： Beatty序列除数问题 Lebesgue测度有理逼近

An Untethered Miniature Soft Jumping Robot Inspired by Quadrupeds

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Journal of Bionic Engineering 2023年第4期20卷 1467-1480页

作者： Tianliang Zhong Fanan Wei Zhushan zhai wenguang Yang school of Mechanical Engineering and Automation Fuzhou UniversityFuzhou350108China school of Electromechanical and Automotive Engineering Yantai UniversityYantai264005ShandongChina State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang110016LiaoningChina

In recent years,designing a soft robot that can jump continuously and quickly explore in a narrow space has been a hot research *** the continuous efforts of researchers,many types of actuators have been developed and successfully employed to actuate the rapid locomotion of soft *** these mechanisms have enabled soft robots with excellent movement capabilities,they largely rely on external energy supply cables,which greatly limits their ***,it is still a big challenge to realize the unconstrained movement of the soft robot and the flexible adjustment of the movement direction in a narrow ***,a wireless magnetically controlled soft jumping robot with single-leg is proposed,which can achieve continuous and rapid jumping ***'s more interesting is that by changing the frequency and waveform of the control signal,this soft robot can easily switch between forward and backward *** motion direction switching function enables the magnetically controlled soft robot to return to the initial position without adjusting the direction when it completes the operation in a narrow pipe or takes the wrong path,which greatly improves the motion efficiency of the soft jumping robot and broadens its application field.

关键词： Wireless Magnetically controlled Soft robot Jumping Bidirectional motion

On the Rankin-Selberg problem:higher power moments of the Riesz mean error term

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Science china Mathematics 2008年第1期51卷 148-160页

作者： TANIGAWA Yoshio zhai wenguang ZHANG DeYu Graduate school of Mathematics Nagoya UniversityNagoya 464-8602Japan school of mathematical sciences Shandong Normal UniversityJinan 250014China

Let Δ1(x;φ) be the error term of the first Riesz mean of the Rankin-Selberg problem. We study the higher power moments of Δ1(x; φ) and derive an asymptotic formula for the 3-rd, 4-th and 5-th power moments by usin... 详细信息

关键词： Rankin-Selberg problem Riesz mean Voronoi type formula power moment

重访非洲文学语言之争——一个社会历史的视角

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山东外语教学 2024年第3期45卷 99-107页

作者：翟乃海山东师范大学外国语学院山东济南250358

语言问题是非洲现代英语文学批评和理论中的焦点问题之一。表面上,非洲文学的语言论争是关于使用英语等欧洲语言还是非洲语言进行文学创作的论战,但它包含语言媒介与非洲审美经验表达、英语与民族团结、文化认同、非洲文学向谁言说等多... 详细信息

语言问题是非洲现代英语文学批评和理论中的焦点问题之一。表面上,非洲文学的语言论争是关于使用英语等欧洲语言还是非洲语言进行文学创作的论战,但它包含语言媒介与非洲审美经验表达、英语与民族团结、文化认同、非洲文学向谁言说等多重维度。它的实质是语言政治和文学功用的问题。从这个角度看,位于论争两端的阿契贝和恩古吉的分歧,不单纯是语言选择的问题。它反映了两人政治倾向和意识形态的冲突,折射出尼日利亚和肯尼亚文化精英对独立后社会未来和共同体的不同想象。

关键词：非洲文学语言之争社会历史阿契贝恩古吉

Strain transfer behavior and crystallographic mechanism of crack initiation during cyclic deformation in zirconium

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Journal of Materials Science & Technology 2023年第31期162卷 234-246页

作者： Xiangkang Zeng Conghui Zhang wenguang Zhu Mingliang Zhu Tongguang zhai Chi Ma Tingchuang Shu KangKai Song school of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Key Laboratory of Pressure Systems and Safety Ministry of EducationSchool of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237China school of Materials Science and Engineering Shandong Jianzhu UniversityJinan 250101China

Fully-reversed cyclic deformation of a pure Zr(a thickness of 17 mm)was conducted at two different strain amplitudes(0.4%and 0.8%)to investigate the deformation and crack initiation behaviors based on slip trace *** was found that prismaticaslip with a higher Schmid Factor(m>0.4)was the dominant deformation *** grains containing persistent slip bands(PSBs)tended to go towards[1210]pole and the Schmid Factor had a critical value of 0.4 above which prismatic and pyramidal slip were *** cracks were mainly initiated at PSBs and grain boundaries(GBs).It showed that 61.1%of the cracks were PSB cracks under a strain amplitude of 0.4%,while it decreased to 53.5%at a strain amplitude of 0.8%.PSB cracks were mainly parallel to prismaticaslip with higher Schmid Factor while some cracks tended to be initiated at GBs with higher misorientation *** interaction of PSBs with GBs would result in strain transferring to the neighboring *** transfer was more likely to occur at the condition of the higher geometrical compatibility factor m,and lower residual Burgers vectorb,which could reduce strain localization.

关键词： Fatigue crack initiation Crystallographic orientation PSBs GBs Strain transfer