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Nano Research 2024年第6期17卷 4943-4950页

作者： Rui Li Xiayan Yan Meng Liu qingkai zhao Jie Du Xinxin Tan Jingwen Ba Rongguang Zeng Wenhua Luo Jingsong Xu Institute of Materials China Academy of Engineering PhysicsJiangyou 621907China Science and Technology on Surface Physics and Chemistry Laboratory Jiangyou 621908China

Top-down strategy has been widely applied for synthesis of metal single atom catalysts(SACs)via converting metal nanoparticles or bulk metals into atomically dispersed ***,we report a simple electrochemical atomic migration strategy for top-down synthesis of SACs via a facile cathodic corrosion process without involving high temperature or harsh *** of metal nanoparticles on cathode are firstly disbanded under high negative voltage,and emitted into the electrolyte in the form of atomic metal anions in Zintl *** escaped atomically dispersed metal species are then oxidized by water molecules and captured by the defects on the pre-added nitrogen doped carbon carriers in the *** cathodic corrosion strategy is confirmed to be suitable for scalable synthesis of kinds of metal SACs(e.g.,Pt,Pd,and Ir)on doped carbon ***,the as-prepared nitrogen doped carbon powder supported Pt SACs exhibit superior catalytic activity toward hydrogen evolution reaction(HER)with a low overpotential of 0.024 V at 10 mA·cm^(−2)and a low Tafel slope of 29.7 mV·dec^(−1)as well as a long-term durability.

关键词： cathodic corrosion top-down strategy powdery single atom catalysts hydrogen evolution reaction scalable synthesis

Analysis of periodic pulsating nanofluid flow and heat transfer through a parallel-plate channel in the presence of magnetic field

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Applied Mathematics and Mechanics(English Edition) 2023年第11期44卷 1957-1972页

作者： qingkai zhao Longbin TAO Hang XU School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100Jiangsu ProvinceChina Department of Naval Architecture Ocean and Marine EngineeringUniversity of StrathclydeGlasgow G4 OLZU.K. State Key Lab of Ocean Engineering School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

In this paper,we focus on the two-dimensional pulsating nanofluid flow through a parallel-plate channel in the presence of a magnetic *** pulsating flow is produced by an applied pressure gradient that fluctuates with a small amplitude.A kind of proper transformation is used so that the governing equations describing the momentum and thermal energy are reduced to a set of non-dimensional *** analytical expressions of the pulsating velocity,temperature,and Nusselt number of nanofluids are obtained by the perturbation *** the present study,the effects of the Cu-H2O and Al_(2)O_(3)-H2O nanofluids on the flow and heat transfer in pulsating flow are compared and *** results show that the convective heat transfer effect of Cu-H2O nanofluids is better than that of Al_(2)O_(3)-H2O ***,the effects of the Hartmann number and pulsation amplitude on the velocity,temperature,and Nusselt number are examined and discussed in *** present work indicates that increasing the Hartmann number and pulsation amplitude can enhance the heat transfer of the pulsating *** addition,selecting an optimal pulsation frequency can maximize the convective heat transfer of the pulsating ***,improved understanding of these fundamental mechanisms is conducive to the optimal design of thermal systems.

关键词： nanofluid pulsating flow heat transfer applied magnetic field

Three-dimensional free bio-convection of nanofluid near stagnation point on general curved isothermal surface

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Applied Mathematics and Mechanics(English Edition) 2016年第4期37卷 417-432页

作者： qingkai zhao Hang XU Longbin TAO A.RAEES Qiang SUN State Key Laboratory of Ocean Engineering Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration(CISSE)School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Marine Science and Technology Newcastle UniversityNewcastle upon Tyne NE1 7RUU.K. Department of Mechanical Engineering National University of Singapore10 Kent Ridge Crescent 119260Singapore

In this paper, the three-dimensional nanofluid bio-convection near a stagnation attachment is studied. With a set of similarity variables, the governing equations embodying the conservation of total mass, momentum, thermal energy, nanoparticles and microorganisms are reduced to a set of fully coupled nonlinear differential equations. The homotopy analysis method （HAM）-finite difference method （FDM） technique is used to obtain exact solutions. The effect of various physical parameters on distribution of the motile microorganisms and the important physical quantities of practical interests are presented and discussed.

关键词： nanofluid stagnation point bioconvection gyrotactic microorganisms,homotopy analysis method (HAM)-finite difference method (FDM)

Platinum single atom catalysts for hydrogen isotope separation during hydrogen evolution reaction

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Nano Research 2022年第5期15卷 3952-3958页

作者： Jingsong Xu Rui Li Xiayan Yan qingkai zhao Rongguang Zeng Jingwen Ba Qifa Pan Xin Xiang Daqiao Meng Science and Technology on Surface Physics and Chemistry Laboratory Jiangyou 621908China Institute of Materials China Academy of Engineering PhysicsJiangyou 621907China

Electrolysis of water is widely used for hydrogen isotope separation and the development of hydrogen evolution reaction(HER)catalysts with high selectivity and activity is of key ***,we propose single atom catalysts(SACs)as promising catalysts for efficient hydrogen isotope *** SACs and Pt nanoparticles(NPs)have been fabricated on nanoarray-structured nitrogen-doped graphite foil(NGF)substrate by a polyol reduction *** as prepared Pt1/NGF electrode exhibits high activity and selectivity toward HER with a low overpotential of 0.022 V at 10 mA·cm^(-2) and a high separation factor of 6.83 for hydrogen and deuterium separation,much better than Pt NPs *** functional theory(DFT)calculations ascribe the high activity and selectivity to the constructed Pt-N_(2)C_(2) *** work develops a new opportunity for the design and application of high-efficiency and stable SACs toward hydrogen isotope separation by electrolysis of water.

关键词： hydrogen isotope separation,single atom catalysts hydrogen evolution reaction polyol reduction separation factor

Cathodic corrosion as a facile and universal method for the preparation of supported metal single atoms

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Nano Research 2022年第3期15卷 1838-1844页

作者： Rui Li Jingsong Xu qingkai zhao Wensheng Ren Rongguang Zeng Qifa Pan Xiayan Yan Jingwen Ba Tao Tang Wenhua Luo Institute of Materials China Academy of Engineering PhysicsJiangyou 621907China Science and Technology on Surface Physics and Chemistry Laboratory Jiangyou 621908China

Top-down strategy has been generally adopted for preparation of metal single atom catalysts(SACs)due to the simplified synthetic process,metal economics,and scalability ***,we propose a general top-down route to convert metal nanoparticles into uniformly dispersed metal single atoms in mild electrochemical environment via a facile cathodic corrosion *** the synthetic process,Pt nanoparticles precursors are transformed into migrating Pt single atoms(Pt1)driven by a high negative potential;and subsequently these mobile Pt atoms are trapped and stabilized by N coordination sites of N-doped carbon paper(NCP).The as-prepared Pt1/NCP electrodes exhibit a superior catalytic activity toward hydrogen evolution reaction(HER)with a low overpotential of 0.022 V at 10 mA/cm^(2)and a low Tafel slope of 28.5 mV/dec as well as a long-term ***,the proposed electrochemical atomic migration strategy shows a promising generality for fabricating other metal single atoms(e.g.,Pd,Ir,Cu),which may open a new avenue for metallic SACs preparation.

关键词： top-down strategy electrochemical atomic migration cathodic corrosion nitrogen doped carbon paper metal single atoms hydrogen evolution reaction

Luminescence regulation of Sb^(3+)in 0D hybrid metal halides by hydrogen bond network for optical anti-counterfeiting

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Opto-Electronic Advances 2024年第3期7卷 15-25页

作者： Dehai Liang Saif M.H.Qaid Xin Yang Shuangyi zhao Binbin Luo Wensi Cai qingkai Qian Zhigang Zang Key Laboratory of Optoelectronic Technology&Systems(Ministry of Education) Chongqing UniversityChongqing 400044China Department of Physics&Astronomy College of SciencesKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia Department of Chemistry and Chemical Engineering Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong ProvinceShantou UniversityShantou 515063China Department of Oil Army Logistics Academy of PLAChongqing 401311China

The Sb^(3+) doping strategy has been proven to be an effective way to regulate the band gap and improve the photophysical properties of organic-inorganic hybrid metal halides(OIHMHs).However,the emission of Sb^(3+) ions in OIHMHs is primarily confined to the low energy region,resulting in yellow or red *** date,there are few reports about green emission of Sb^(3+)-doped ***,we present a novel approach for regulating the luminescence of Sb^(3+) ions in 0D C_(10)H_(2)_(2)N_(6)InCl_(7)·H_(2)O via hydrogen bond network,in which water molecules act as agents for hydrogen ***^(3+)-doped C_(10)H_(2)2N_(6)InCl_(7)·H_(2)O shows a broadband green emission peaking at 540 nm and a high photoluminescence quantum yield(PLQY)of 80%.It is found that the intense green emission stems from the radiative recombination of the self-trapped excitons(STEs).Upon removal of water molecules with heat,C_(10)H_(2)_(2)N_(6)In_(1-x)Sb_(x)Cl_(7) generates yellow emis-sion,attributed to the breaking of the hydrogen bond network and large structural distortions of excited *** water molecules are adsorbed by C_(10)H_(2)_(2)N_(6)In_(1-x)Sb_(x)Cl_(7),it can subsequently emit green *** water-induced reversible emission switching is successfully used for optical security and information *** findings expand the under-standing of how the local coordination structure influences the photophysical mechanism in Sb^(3+)-doped metal halides and provide a novel method to control the STEs emission.

关键词： indium-based halides Sb^(3+)doping hydrogen bonding network optical anti-counterfeiting

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制造商公平关切下的供应链契约协调研究

计算机集成制造系统 2024年第1期30卷 369-378页

作者：曹凯吉清凯赵达胡祥培海南大学国际商学院海南海口570228 海南省公司治理研究院海南海口570228 大连理工大学经济与管理学院辽宁大连116024

针对制造商公平关切下的二级供应链,构建非合作博弈模型,考察批发价契约与收益共享契约的供应链协调功能。通过逆向归纳求解博弈均衡,分析发现:与零售商公平关切时不同,制造商公平关切时批发价契约总是无法协调供应链,制造商将利用其先... 详细信息

针对制造商公平关切下的二级供应链,构建非合作博弈模型,考察批发价契约与收益共享契约的供应链协调功能。通过逆向归纳求解博弈均衡,分析发现:与零售商公平关切时不同,制造商公平关切时批发价契约总是无法协调供应链,制造商将利用其先动优势使得自己总是处于优势不公平(即其利润总大于零售商);当市场潜在需求足够大,且制造商的优势不公平感知足够强时,若令收益共享率为1/2,且制造商以成本价供货,则该收益共享契约可实现供应链协调。

关键词：公平关切批发价收益共享供应链协调

Whole-genome Sequencing Reveals Autooctoploidy in Chinese Sturgeon and Its Evolutionary Trajectories

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Genomics, Proteomics & Bioinformatics 2024年第1期22卷 51-65页

作者： Binzhong Wang Bin Wu Xueqing Liu Yacheng Hu Yao Ming Mingzhou Bai Juanjuan Liu Kan Xiao qingkai Zeng Jing Yang Hongqi Wang Baifu Guo Chun Tan Zixuan Hu Xun zhao Yanhong Li Zhen Yue Junpu Mei Wei Jiang Yuanjin Yang Zhiyuan Li Yong Gao Lei Chen Jianbo Jian Hejun Du Hubei Key Laboratory of Three Gorges Project for Conservation of Fishes Yichang 443100China Chinese Sturgeon Research Institute China Three Gorges CorporationYichang 443100China Yangtze River Biodiversity Research Center China Three Gorges CorporationWuhan 430014China BGI-Shenzhen Shenzhen 518083China BGI Genomics BGI-ShenzhenShenzhen 518083China Department of Biotechnology and Biomedicine Technical University of DenmarkLyngby 2800Denmark River Basin Complex Administration Center China Three Gorges CorporationYichang 443100China BGI-Sanya BGI-ShenzhenSanya 572025China Yangtze Eco-Environment Engineering Research Center China Three Gorges CorporationBeijing 100038China

The order Acipenseriformes,which includes sturgeons and paddlefishes,represents“living fossils”with complex genomes that are good models for understanding whole-genome duplication(WGD)and ploidy evolution in ***,we sequenced and assembled the first high-quality chromosome-level genome for the complex octoploid Acipenser sinensis(Chinese sturgeon),a critically endangered species that also represents a poorly understood ploidy group in *** results show that *** is a complex autooctoploid species containing four kinds of octovalents(8n),a hexavalent(6n),two tetravalents(4n),and a divalent(2n).An analysis taking into account delayed rediploidization reveals that the octoploid genome composition of Chinese sturgeon results from two rounds of homologous WGDs,and further provides insights into the timing of its ploidy *** study provides the first octoploid genome resource of Acipenseriformes for understanding ploidy compositions and evolutionary trajectories of polyploid fishes.

关键词： Chinese sturgeon Whole-genome sequencing Autooctoploid Polyploidization and diploidization Whole-genome duplication

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多相流量计在国内市场的应用及发展趋势

石油与天然气化工 2017年第2期46卷 99-104页

作者：许晓英赵庆凯陈丰波孔冰中海石油(中国)有限公司天津分公司

由于多相流测量技术越来越成熟,国内外品牌各有特点,适用场合各有不同,在选用多相流量计时,根据实际需要选出最适用的品牌种类尤为关键。通过阐述目前国内使用较多的几种多相流量计的原理、特点及应用,对多相流量计的选型因素及发展趋... 详细信息

由于多相流测量技术越来越成熟,国内外品牌各有特点,适用场合各有不同,在选用多相流量计时,根据实际需要选出最适用的品牌种类尤为关键。通过阐述目前国内使用较多的几种多相流量计的原理、特点及应用,对多相流量计的选型因素及发展趋势进行了深入研究,给出了基于完全混合模型、基于部分分离模型和基于完全分离模型3种方向,以指导选型与未来的发展方向,为今后多相流量计的选型使用提供参考。

关键词：多相流量计原理特点应用选型发展趋势

正火型V-N-Ti和Nb-V-Ti海工钢焊接粗晶热影响组织和韧性研究

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材料研究学报 2020年第12期34卷 939-948页

作者：师仲然赵庆凯刘登辉王天琪柴希阳罗小兵柴锋钢铁研究总院工程用钢研究所北京100081 国家新材料生产应用示范平台(先进海工与高技术船舶材料) 洛阳471000 中海石油(中国)有限公司天津分公司天津300452

用焊接热模拟方法研究了V-N-Ti和Nb-V-Ti微合金化正火型海工钢模拟粗晶热影响区(CGHAZ)组织和韧性的变化规律。结果表明,组织的不同使V-N-Ti设计正火型海工钢的模拟CGHAZ韧性比Nb-V-Ti钢的好。对于V-N-Ti钢,较高的N含量提高了富Ti(Ti,V)... 详细信息

用焊接热模拟方法研究了V-N-Ti和Nb-V-Ti微合金化正火型海工钢模拟粗晶热影响区(CGHAZ)组织和韧性的变化规律。结果表明,组织的不同使V-N-Ti设计正火型海工钢的模拟CGHAZ韧性比Nb-V-Ti钢的好。对于V-N-Ti钢,较高的N含量提高了富Ti(Ti,V)(C,N)粒子析出温度和铁素体形核能力,使模拟CGHAZ原始奥氏体晶粒和(取向差角为15°)晶粒细化,并生成能阻止或使解理裂纹的偏转细小多边形铁素体,因此具有良好的低温韧性。而Nb-V-Ti钢模拟CGHAZ原奥氏体晶界上的链状M-A、粗大的原始奥氏体晶粒和有效晶粒尺寸,是模拟CGHAZ韧性差的原因。

关键词：金属材料 V-N-Ti钢正火型粗晶热影响区多边形铁素体