检索结果-南通市图书馆

Microstructure and Internal Friction Behavior of Laser 3D Printed Fe-Based Amorphous composites

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 196-204页

作者： Shuilong huang Qingjun chen Li Ji Kan Wang Guosheng huang School of Material Science and Engineering Nanchang Hangkong UniversityNanchang330063China State Key Laboratory for Marine corrosion and Protection Luoyang Ship Material Research Institute(LSMRI)Qingdao266237China

Laser 3D printing,also known as laser additive manufacturing(LAM),is favored for its ability to form bulk metallic glass(BMG)and its composite materials(BMGcs)with freeform *** this work,two different kinds of Fe_(41)co_(7)cr_(15)Mo_(14)c_(15)B_(6)Y_(2)amorphous coatings(A and B)were prepared by using LAM technology under air-and water-cooled conditions,respectively;meanwhile,to reduce the cracks generated due to the residual thermal stresses,coating c obtained by air-sweep annealing of B with a low energy-density *** morphology and amorphous content and microstructure of the coatings were investigated,the results show many cracks in coating B deposited under water-cooled conditions,and its microstructure shows an amorphous-crystal-nanocrystalline mixed *** was suppressed in coating c,obtained by air-sweep annealing based on coating B,but the amorphous content was reduced from 32.6 to 13.4%.And the hardness and corrosion resistance of the coating will increase with the increase in the amorphous ***,the internal friction behavior of a BMGcs was prepared on the basis of the process of sample c is compared with that of as-cast amorphous *** results show that the low temperature internal friction behavior of BMGcs is affected by the defects produced during printing,and the high temperature internal friction behavior is affected by the precipitated hard phase.

关键词： Laser 3D printing Amorphous coating Microstructure corrosion resistance Internal friction behavior

Efficient guiding and focusing of intense laser pulse using periodic thin slits

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu T.W.huang K.Jiang c.N.Wu H.Peng P.c.hen R.Li H.B.Zhuo c.T.Zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material Technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

Access to High-Molecular-Weight Polyethylenes through High Temperature Ethylene Polymerization catalysed by Ethylene-Bridged ansa-(3-R-cyclopentadienyl)(Fluorenyl) Zirconocene complexes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

chinese Journal of Polymer Science 2024年第1期42卷 42-51,I0007页

作者： Bo Li Haiyan Ma Jiling huang Shanghai Key Laboratory of Functional Materials chemistry and Laboratory of Organometallic chemistry School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

A series of c1-symmetric ethylene-bridged ansa-(3-R-cyclopentadienyl)(fluorenyl) metallocene complexes(Zr: 1-5;Hf: 6) have been synthesized, characterized and investigated as catalyst precursors for the high temperature ethylene polymerization. Using methylaluminoxane(MAO) as the cocatalyst, zirconium complexes 1-5 bearing a bulky substituent on the 3-position of the cyclopendienyl ring showed high catalytic activities up to 1.48×10^(7) g PE·mol_(Zr)^(-1)·h^(-1) toward the polymerization of ethylene and afforded polyethylenes with high molecular weights(1.49×10^(5)-6.31×10^(5) g/mol), meanwhile exhibting great thermal stability at high temperatures up to 120 ℃ together with a long catalytic life time up to 2 h. By adopting low Al/Zr ratios, such as 125, polyethylenes with ultra high molecular weights up to 2.86×106 g/mol were obtained. It is worthy of noting that zirconium complexes 1-4 bearing a substituent with an aryl pendant showed temperature-dependent activities, which increased rapidly with the increase of polymerization temperature, thus weak interaction of the pendent aryl group with the cationic active center is proposed to account for the very low activities displayed at low temperatures. In contrast to zirconocene complexes 1-5, hafnocene complex 6 only displayed very low catalytic activities toward the polymerization of ethylene and afforded polyethylenes with molecular weights ten times smaller than those obtained by zirconocene complexes 1-5. Zirconocene complexes 1-5 were also able to catalyse the polymerization of propylene at high temperatures, but only afforded waxes with low molecular weights.

关键词： ansa-Metallocene Ethylene Propylene Polymerization High temperature

Time-of-flight resolved stimulated Raman scattering microscopy using counter-propagating ultraslow Bessel light bullets generation

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2024年第7期13卷 1427-1440页

作者： Shulang Lin Li Gong Zhiwei huang Optical Bioimaging Laboratory Department of Biomedical EngineeringCollege of Design and EngineeringNational University of SingaporeSingapore 117576Singapore

We present a novel time-of-flight resolved Bessel light bullet-enabled stimulated Raman scattering(B2-SRS)microscopy for deeper tissue 3D chemical imaging with high resolution without a need for mechanical *** accomplish the tasks,we conceive a unique method to enable optical sectioning by generating the counterpropagating pump and Stokes Bessel light bullets in the sample,in which the group velocities of the Bessel light bullets are made ultraslow(e.g.,vg≈0.1c)and tunable by introducing programmable angular dispersions with a spatial light *** theoretically analyze the working principle of the collinear multicolor Bessel light bullet generations and velocity controls with the relative time-of-flight resolved detection for SRS 3D deep tissue *** have also built the B2-SRS imaging system and present the first demonstration of B2-SRS microscopy with Bessel light bullets for 3D chemical imaging in a variety of samples(e.g.,polymer bead phantoms,biological samples such as spring onion tissue and porcine brain)with high *** B2-SRS technique provides a>2-fold improvement in imaging depth in porcine brain tissue compared to conventional SRS *** method of optical sectioning in tissue using counter-propagating ultraslow Bessel light bullets developed in B2-SRS is generic and easy to perform and can be readily extended to other nonlinear optical imaging modalities to advance 3D microscopic imaging in biological and biomedical systems and beyond.

关键词： Bessel resolved propagating

Discovery potential of the Glashow resonance in an air shower neutrino telescope

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

chinese Physics c 2024年第8期48卷 266-275页

作者： Guo-Yuan huang School of Mathematics and Physics China University of GeosciencesWuhan 430074China Max-Planck-Institut für Kernphysik Saupfercheckweg 169117 HeidelbergGermany

The in-ice or in-water cherenkov neutrino telescope,such as Icecube,has already proved its power in measuring the Glashow resonance by searching for the bump around E_(ν)=6.3PeV arising from the W-boson *** are many proposals for the next few decades for observations of cosmic tau neutrinos with extensive air showers,also known as tau neutrino *** air shower telescope is,in principle,sensitive to the Glashow resonance via the channel W→τν_(τ)followed by the tau decay in the air(e.g.,TAMBO,which has a geometric area of approximately 500km^(2)).Using a thorough numerical analysis,we find that the discovery significance can be up to 90%with a TAMBO-like setup if PeV neutrinos primarily originate from neutron decays,considering the flux parameters measured by Icecube as the *** presence of new physics affecting the neutrino flavor composition can also increase the ***,if ultrahigh-energy neutrinos are dominantly produced from meson decays,it will be statistically difficult for an advanced proposal such as TAMBO to discriminate the Glashow resonance induced byν¯e from the intrinsicντ/ν¯_(τ)*** have identified several limitations for such advanced telescopes,in comparison with the in-ice or in-water telescope,when measuring resonances:(i)a suppressed branching ratio of 11%for the decay W→τν_(τ);(ii)the smearing effect and reduced acceptance because the daughter neutrino takes away(y)∼75%of the energy from the W decay;and(iii)a large attenuation effect for Earth-skimming neutrinos with the resonance.

关键词： Ultrahigh-energy neutrinos Neutrino telescopes Glashow resonance

Materials-oriented integrated design and construction of structures in civil engineering—A review

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Structural and civil Engineering 2022年第1期16卷 24-44页

作者： Xing MING John c.huang Zongjin LI Institute of Applied Physics and Materials Engineering University of MacaoMacao SAR 999078China cHc Engineering LLCFairfaxVA 20030USA

Design is a goal-oriented planning activity for creating products,processes,and systems with desired functions through *** is a decision-making exploration:the design outcome may vary greatly depending on the designer’s knowledge and *** design is one type of design philosophy that takes an interdisciplinary and holistic *** civil engineering,structural design is such an activity for creating buildings and ***,structural design in many countries has emphasized a performance-based philosophy that simultaneously considers a structure’s safety,durability,serviceability,and ***,integrated design in civil engineering has become more popular,useful,and ***-oriented integrated design and construction of structures(MIDcS)combine materials engineering and structural engineering in the design stage:it fully utilizes the strengths of materials by selecting the most suitable structural forms and construction *** paper will explore real-world examples of MIDcS,including the realization of MIDcS in timber seismic-resistant structures,masonry arch structures,long-span steel bridges,prefabricated/on-site extruded light-weight steel structures,fiber-reinforced cementitious composites structures,and fiber-reinforced polymer bridge ***,advanced material design methods such as bioinspired design and structure construction technology of additive manufacturing are briefly reviewed and discussed to demonstrate how MIDcS can combine materials and structures.A unified strengthdurability design theory is also introduced,which is a human-centric,interdisciplinary,and holistic approach to the description and development of any civil infrastructure and includes all processes directly involved in the life cycle of the ***,this paper lays out future research directions for further development in the field.

关键词： integrated design and construction fiber-reinforced concrete fiber-reinforced polymer light-weight steel structures digital fabrication composites

competitive assembling strategy to construct carbon nitride homojunctions for boosting photocatalytic performance

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第5期172卷 23-32页

作者： Hua-Wei Zhang Yuan-Yuan Li Bo Li Jing-Hui Shi Tao huang Gui-Fang huang Anlian Pan Wangyu Hu Wei-Qing huang School of Physics&Electronic Engineering Zhengzhou University of Light IndustryZhengzhou 450002China Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education&Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics and Devices School of Physics and ElectronicsHunan UniversityChangsha 410082China college of Materials Science and Engineering Hunan UniversityChangsha 410082China

Both morphology and composition have a great influence on the properties and functions of materials,however,how to rational modulate both of them to achieve their synergistic effects has been a longstanding ***,we demonstrate a competitive assembling strategy for the construction of metal-free graphite carbon nitride(cN)homojunctions in which morphology and composition can be easily controlled simultaneously by only changing the ratio of assembly raw *** homojunctions are comprised of porous nanotubular S-doped cN(ScN)grafted with cN nanovesicles,which are derived from thermal polycondensation of melamine-thiocyanuric acid(M-T)/melamine-cyanuric acid(M-c)supramolecular hybrid *** unique architecture and component engineering endows the novel ScN-cN homojunction with abundant active sites,enhanced visible trapping ability,and intimate interface *** a result,the synthesized ScN-cN homojunctions demonstrate high photocatalytic activity for hydrogen evolution and pollutant *** developed strategy opens up intriguing opportu-nities for the rational construction of intricate metal-free heterostructures with controllable architecture and interfacial contact for applications in energy-related fields.

关键词： competitive assembling strategy Supramolecular hybrid blocks Homojunctions Graphite carbon nitride Photocatalytic

On Hamiltonian Property of cayley Digraphs

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2024年第2期40卷 547-556页

作者： Fang DUAN Qiong-xiang huang School of Mathematics Science Xinjiang Normal UniversityUrumqi 830017China college of Mathematics and Systems Science Xinjiang UniversityUrumqi 830017China

Let G be a finite group generated by S and c(G,S) the cayley digraphs of G with connection set *** this paper,we give some sufficient conditions for the existence of hamiltonian circuit in c(G,S),where G=Zm×H is a semiproduct of Zmby a subgroup H of *** particular,if m is a prime,then the cayley digraph of G has a hamiltonian circuit unless G=Zm×*** addition,we introduce a new digraph operation,called φ-semiproduct of Γ1by Γ2and denoted by Γ1×Γ_φΓ2,in terms of mapping φ:V(Γ2)→{1,-1}.Furthermore we prove that c(Zm,{a})×_φ c(H,S) is also a cayley digraph if φ is a homomorphism from H to{1,-1} ≤ Zm~*,which produces some classes of cayley digraphs that have hamiltonian circuits.

关键词： cayley digraphs hamiltonian circuit external semidirect product

Homological Transfer between Additive categories and Higher Differential Additive categories

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第5期40卷 1325-1344页

作者： Xi TANG Zhao Yong huang School of Science Guilin University of Aerospace TechnologyGuilin 541004P.R.China Department of Mathematics Nanjing UniversityNanjing 210093P.R.China

Given an additive category c and an integer n≥*** higher differential additive category consists of objects X in c equipped with an endomorphism ϵ_(X)satisfying ϵ_(X)^(n).Let R be a,finite-dimensional basic algebra over an algebraically closed field and T the augmenting functor from the category of finitely generated left R-modules to that of finitely generated left R/(t^(n))-*** is proved that a finitely generated left R-module M isτ-rigid(respectively,(support)τ-tilting,almost completeτ-tilting)if and only if so is T(M)as a left R[t]/(t^(n))-***,R isτm-selfinjective if and only if so is R[t]/(t^(n)).

关键词： Higher differential objects Wakamatsu tilting subcategories G_(ω)-projective modules sup-portτ-tilting modules τ_(m)-selfinjective algebras precluster tilting subcategories