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Shape memory effect of dual-phase NiMnGaTb ferromagnetic shape memory alloys

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Journal of Iron and Steel Research International 2019年第3期26卷 321-328页

作者： Jiang Zhang yong-hong ma Ruo-lin Wu Jing-min Wang Institute of Higher Education Beihang UniversityBeijing 100191China School of materials Science and Engineering Beihang UniversityBeijing 100191China Central Iron&Steel Research Institute Beijing 100081China

The evolution of microstructure,reverse martensitic transformation and the conelated influence on shape memory effect was investigated in as-cast and directionally solidified dual-phase NiMnGaTb *** directionally solidified alloys exhibit single-crystal microstructure,preferred dendrite microstructure,and mussy dendrite microstructure in the specimens grown at a withdrawal rate(v)of 10,50 and 200,and 1000μm/s,*** precipitates dispersively distribute in the martensite matrix for the directionally solidified *** the refined grains and particle precipitates,the reverse martensitic transformation gradually shifts to lower temperatures and the temperature span is significantly *** directional solidification technology can effectively enhance the strains recovered due to shape memory effect C;sme)and decrease the compressive stress required to trigger the reorientation of twins(δ)via the realization of preferred orientation,while the maximalεsme and minimumδcan reach 4.96%and 14 MPa in v=10μm/s specimens,*** formation of dendrite morphology degrades the shape memory strain,andεsme decreases with the growth of secondary dendritic arms.

关键词： NiMnGaTb alloy Directional solidification Dual-phase microstructure Shape memory effect

Preparation of spin squeezed state in SiV centers coupled by diamond waveguide

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Chinese Physics B 2021年第10期30卷 165-170页

作者： yong-hong ma Yuan Xu Quan-Zhen Ding Yu-Sui Chen School of Science Inner Mongolia University of Science and TechnologyBaotou 014010China Department of Physics and Center for Quantum Science and EngineeringStevens Institute of TechnologyHobokenNJ 07030USA Department of Physics New York Institute of TechnologyOld WestburyNY 11568USA

Spin squeezing is a fascinating manifestation of many-particle entanglement and one of the most promising quantum *** this paper,we propose a novel realization of a solid-state quantum spin squeezing by applying SiV centers embedded in a diamond waveguide with the help of a microwave *** phenomena about the generation of spin squeezing are analyzed numerically in markovian *** analysis shows that spin squeezing can be generated with the microwave field’s help under some realistic conditions,despite the presence of dephasing and mechanical *** solid-state spin squeezing based on SiV centers in diamonds might be applied to magnetometers,interferometry,and other precise measurements.

关键词： spin squeezed state SiV center diamond waveguide

Research on casing deformation prevention technology based on cementing slurry system optimization

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Petroleum Science 2024年第2期21卷 1231-1240页

作者： Yan Yan Meng Cai Wen-Hai ma Xiao-Chuan Zhang Li-hong Han yong-hong Liu State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment materials CNPC Tubular Goods Research InstituteXi©an710077ShaanxiChina College of Mechanical and Electrical Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Shale Gas Evaluation and Exploitation Key Laboratory of Sichuan Province Chengdu610095SichuanChina CNPC Daqing Oilfield Company Daqing163453HeilongjiangChina

The casing deformation prevention technology based on the optimization of cement slurry is proposed to reduce the casing deformation of shale oil and gas wells during hydraulic fracturing. In this paper, the fracture mechanism of hollow particles in cement sheath was firstly analyzed by discrete element method, and the effect of hollow particles in cement on casing deformation was investigated by laboratory experiment method. Finally, field test was carried out to verify the improvement effect of the casing deformation based on cement slurry modification. The results show that the formation displacement can be absorbed effectively by hollow particles inside the cement transferring the excessive deformation away from casing. The particles in the uncemented state provide deformation space during formation slipping. The casing with diameter of 139.7 mm could be passed through by bridge plug with the diameter of 99 mm when the mass ratio of particle/cement reaches 1:4. According to the field test feedback, the method based on optimization of cement slurry can effectively reduce the risk of casing deformation, and the recommended range of hollow microbeads content in the cement slurry is between 15% and 25%.

关键词： Cement slurry Hollow ceramsite Casing deformation Formation slip Field test

Nuclear phylogenomics of angiosperms and insights into their relationships and evolution

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Journal of Integrative Plant Biology 2024年第3期66卷 546-578页

作者： Guojin Zhang hong ma College of Life Sciences Hunan Normal UniversityChangsha 410081China Department of Biology 510 Mueller LaboratoryHuck Institutes of the Life SciencesThe Pennsylvania State UniversityUniversity ParkPA 16802USA

Angiosperms(flowering plants) are by far the most diverse land plant group with over 300,000 species. The sudden appearance of diverse angiosperms in the fossil record was referred to by Darwin as the “abominable mystery,”hence contributing to the heightened interest in angiosperm evolution. Angiosperms display wide ranges of morphological, physiological,and ecological characters, some of which have probably influenced their species richness. The evolutionary analyses of these characteristics help to address questions of angiosperm diversification and require well resolved phylogeny. Following the great successes of phylogenetic analyses using plastid sequences,dozens to thousands of nuclear genes from next-generation sequencing have been used in angiosperm phylogenomic analyses, providing well resolved phylogenies and new insights into the evolution of angiosperms. In this review we focus on recent nuclear phylogenomic analyses of large angiosperm clades, orders, families,and subdivisions of some families and provide a summarized Nuclear Phylogenetic Tree of Angiosperm Families. The newly established nuclear phylogenetic relationships are highlighted and compared with previous phylogenetic results. The sequenced genomes of Amborella,Nymphaea, Chloranthus, Ceratophyllum, and species of monocots, magnoliids, and basal eudicots, have facilitated the phylogenomics of relationships among five major angiosperms clades. All but one of the 64 angiosperm orders were included in nuclear phylogenomics with well resolved relationships except the placements of several orders. Most families have been included with robust and highly supported placements, especially for relationships within several large and important orders and ***, we examine the divergence time estimation and biogeographic analyses of angiosperm on the basis of the nuclear phylogenomic frameworks and discuss the differences compared with previous analyses. Furthermore,we discuss the implicatio

关键词： angiosperms evolution flowering plants nuclear gene phylogenomics phylogeny

Elastic wave insulation and propagation control based on the programmable curved-beam periodic structure

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Applied mathematics and Mechanics(English Edition) 2024年第10期45卷 1791-1806页

作者： Jiajia maO hong CHENG Tianxue ma Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures Department of Mechanics School of Mathematics Statistics and MechanicsBeijing University of Technology Department of Mechanics School of Physical Science and EngineeringBeijing Jiaotong University

Curved-beams can be used to design modular multistable metamaterials(MMMs) with reprogrammable material properties, i.e., programmable curved-beam periodic structure(PCBPS), which is promising for controlling the elastic wave *** PCBPS is theoretically equivalent to a spring-oscillator system to investigate the mechanism of bandgap, analyze the wave propagation mechanisms, and further form its geometrical and physical criteria for tuning the elastic wave propagation. With the equivalent model, we calculate the analytical solutions of the dispersion relations to demonstrate its adjustability, and investigate the wave propagation characteristics through the PCBPS. To validate the equivalent system, the finite element method(FEM) is *** is revealed that the bandgaps of the PCBPS can be turned on-and-off and shifted by varying its physical and geometrical characteristics. The findings are highly promising for advancing the practical application of periodic structures in wave insulation and propagation control.

关键词： 74J05 74Q10 curved-beam based periodic structure dispersion relation equivalent stiffness O326 spring-oscillator system wave propagation

The Extension Dimension of Subcategories and Recollements of Abelian Categories

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Acta mathematica Sinica,English Series 2024年第4期40卷 1042-1058页

作者： Xin ma Ye Yang PENG Zhao yong HUANG College of Science Henan University of EngineeringZhengzhou 451191P.R.China Department of mathematics Nanjing UniversityNanjing 210093P.R.China

We investigate the behavior of the extension dimension of subcategories of abelian categories under ***Λ',Λ,Λ"be art in algebras such that(modΛ',mod A,modΛ")is a recollement,and let D'and D"be subcategories of modΛand modΛ"*** any n,m≥0,under some conditions,we get dimΩ^(k)(D)≤dimΩ^(n)(D')+dimΩ^(m)(D")+1,where k=max{m,n}and D is the subcategory of modΛglued by D'and D";moreover,we give a sufficient condition such that the converse inequality holds *** applications,some results for Igusa-Todorov subcategories and syzygy finite sub categories are obtained.

关键词： Recollements extension dimension Igusa–Todorov subcategories syzygy finite subcategories

Geochemical characteristics,generation,and evolution mechanism of coalbed methane in the south-western Ordos Basin,China

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Frontiers of Earth Science 2024年第2期18卷 296-311页

作者： Yabing LIN yong QIN Dongmin ma Shengquan WANG College of Geology and Environment Xi’an University of Science and TechnologyXi’an 710054China Key Laboratory of Coalbed Methane Resource and Reservoir Formation Process(the Ministry of Education) China University of Mining and TechnologyXuzhou 221008China Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation Xi’an 710054China

The south-western Ordos Basin is rich in low-middle rank coalbed methane(CBM)resources;while the geochemical characteristics and genetic mechanism of CBM are not ***,according to geological and geochemical test data from gas and coal seam water from CBM wells in Bingchang,Jiaoxun,Huangling,yonglong,and Longdong minging areas,we systematically studied the geochemical characteristics,generation,and evolution mechanism of CBM in Jurassic Yan’an Formation in the south-western Ordos *** results show that the CH4 content of whole gas is in the range of 42.01%-94.72%.The distribution ranges of theδ^(13)C-CH_(4)value is−87.2‰to−32.5‰,indicating diverse sources of thermogenic gas and biogenic *** microbial methane is mainly generated by a CO_(2)reduction pathway,with certain methyl-type fermentation ***δ^(13)C-CH_(4)has a positive correlation with burial depth,indicating the obvious fractionation of *** relationship between the genetic types and burial depth of the CBM reservoir indicates that the favorable depth of secondary biogenic gas is less than 660 *** Late Cretaceous Yanshanian Movement led to the uplift of the Ordos Basin,and a large amount of thermogenic gas escaped from the edge of the *** the Paleogene Period,the coal reservoir in the basin margin has received recharge from atmospheric precipitation,which is favorable for the formation of secondary biogenic *** deep area,generally under 1000 m,mainly contains residual thermogenic *** intermediate transition zone is mixed *** by the tectonic background,the genetic types of CBM in different mining areas are controlled by the coupling of burial depth,coal rank,and hydrogeological *** Binchang mining area contains biogenic gas,and the development of CBM has achieved initial success,indicating that similar blocks with biogenic gas formation conditions is key to the efficient development of *** research results provide a scientific basis for

关键词： coalbed methane stable isotopes geochemistry generation and evolution mechanism Ordos Basin

Developing Core-Shell Nano-Structures in FeCrAl-ODS Ferritic Alloys with the Co-Addition of Ni and Zr

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 364-372页

作者： Wenquan Ding Jieli ma yong Jiang Yiren Wang Huiqun Liu Key Laboratory for Nonferrous materials of Ministry of Education School of Materials Science and EngineeringCentral South UniversityChangsha410083China National Key Laboratory for Powder Metallurgy Central South UniversityChangsha410083China

A new Ni+Zr co-alloyed FeCrAl-ODS(oxide-dispersion-strengthened)ferritic alloy was fabricated by ball-milling and *** electron microscopy and atom probe tomography,the dispersive formation of high density core-shelled nano-particles of various sizes was confirmed with a common B2-NiAl *** which,median-sized nano-particles(20-50 nm)typically have an Y_(4)Al_(2)O_(9)nano-core ofmated as~2×10^(23)m^(-3)with a mean size of 6.3 nm only,and accordingly,the new alloy achieved an excellent combination of strength and ductility at high temperatures.

关键词： FeCrAl Oxide-dispersion-strengthened(ODS)alloy Mechanical alloying Nano-oxides Core-shell

A progressive framework for rotary motion deblurring

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Defence Technology（防务技术） 2024年第2期32卷 159-172页

作者： Jinhui Qin yong ma Jun Huang Fan Fan You Du School of Electronic Information Wuhan UniversityWuhan430072China

The rotary motion deblurring is an inevitable procedure when the imaging seeker is mounted in the rotating *** rotary motion deblurring methods suffer from ringing artifacts and noise,especially for large blur *** solve the above problems,we propose a progressive rotary motion deblurring framework consisting of a coarse deblurring stage and a refinement *** the first stage,we design an adaptive blur extents factor(BE factor)to balance noise suppression and details *** a novel deconvolution model is proposed based on BE *** the second stage,a triplescale deformable module CNN(TDM-CNN)is designed to reduce the ringing artifacts,which can exploit the 2D information of an image and adaptively adjust spatial sampling *** establish a standard evaluation benchmark,a real-world rotary motion blur dataset is proposed and released,which includes rotary blurred images and corresponding ground truth images with different blur *** results demonstrate that the proposed method outperforms the state-of-the-art models on synthetic and real-world rotary motion blur *** code and dataset are available at https://***/JinhuiQin/RotaryDeblurring.

关键词： Rotary motion deblurring Progressive framework Blur extents factor TDM-CNN