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stellar X-ray sources in the Rosette Nebula

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Chinese journal of Astronomy and Astrophysics 2004年第2期4卷 153-165页

作者： W.p.Chen p.s.Chiang j.z.Li Institute of Astronomy National Central UniversityChung-Li 32054Taiwan National Astronomical Observatories Chinese Academy of SciencesBeijing 100012

We present optical photometric and spectroscopic studies of ROsAT X-ray stellar sources in the Rosette Nebula star-forming region. The brightest X-ray sources are either massive stars or active T Tauri stars associated with the open cluster NGC 2244, or are foreground stars. some of the spectra of the young stars newly identified in the region are presented.

关键词： stars: early-type stars: pre-main sequence stars: formation HII regions

Macrophage invasion:here,there and everywhere

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signal Transduction and Targeted Therapy 2022年第8期7卷 2634-2635页

作者： Lola C.Hernandez pablo j.sáez Cell Communication and Migration Laboratory Institute of Biochemistry and Molecular Cell BiologyCenter for Experimental MedicineUniversity Medical Center HamburgEppendorfHamburgGermany

Recently Akhmanova et *** in science that cell division at specific locations in the tissue constitutes a novel strategy for macrophage infiltration.1 Cell infiltration or tissue invasion is a common migratory strategy used by highly motile *** cellular response is observed in tissue colonization during development,drives intra/extravasation of leukocytes during the immune response and is exploited by tumors for *** cells employ diverse mechanisms to invade tissues,including degradation or deformation of the extracellular matrix(ECM)and cell squeezing through small pores.2 Leukocytes are professional migrating cells able to find their way through tissues with different topologies and levels of *** their nucleus,the largest and stiffest organelle in a cell,leukocytes probe the microenvironment and choose the path of least resistance when moving through small pores.

关键词： invasion al. pores

Examining the effect of the aging state on strength and plasticity of wrought aluminum alloys

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journal of Materials science & Technology 2022年第27期122卷 54-67页

作者： z.Qu z.j.zhang j.X.Yan p.zhang B.s.Gong s.L.Lu z.F.zhang T.G.Langdon shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China school of Materials science and Engineering University of Science and Technology of ChinaShenyang 110016China Department of Mechanical Engineering University of SouthamptonSouthampton SO171BJUnited Kingdom

A general rule of strength and plasticity was proposed for three typical wrought Al alloys(2xxx,6xxx,and 7xxx)subjected to different aging *** of the work-hardening processes and dislocation configurations in tensile and compressive testing reveal that this general rule arises because there is a common mechanism for these three kinds of wrought alloys whereby the tendency for cross-slip increases monotonously with aging *** analyzing the strain hardening exponent and the stacking fault energy,it is demonstrated that the change in the dislocation slip mode is attributed mainly to the formation of second phases rather than to the matrix ***,a new work-hardening model was proposed for wrought Al alloys containing second phases and this explains the interaction between dislocations and second phases and other relevant experimental *** work is therefore beneficial for quantitatively investigating and optimizing the strength and plasticity of wrought aluminum alloys.

关键词： Wrought aluminum alloy strength and plasticity Work hardening Dislocation slip mode second phase

An efficient spH methodology for modelling mechanical characteristics of particulate composites

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Defence Technology（防务技术） 2021年第1期17卷 135-146页

作者： z.j.zheng s.Kulasegaram p.Chen Y.Q.Chen Department of Mechanics College of Mechanical EngineeringChongqing University of TechnologyChongqing400054China Institute of Applied and Computational Mechanics Cardiff School of EngineeringCardiff UniversityQueen’s BuildingsThe ParadeCardiffCF243AAWalesUK Department of Mechanics and Engineering science College of EngineeringPeking UniversityBeijing100871China

particulate composites are one of the widely used materials in producing numerous state-of-the-art components in biomedical,automobile,aerospace including defence *** of modelling techniques have been adopted in the past to model mechanical behaviour of particulate *** to their favourable properties,particle-based methods provide a convenient platform to model failure or fracture of these *** particle hydrodynamics(spH)is one of such methods which demonstrate excellent potential for modelling failure or fracture of particulate composites in a Lagrangian *** of the major challenges in using spH method for modelling composite materials depends on accurate and efficient way to treat interface and boundary *** this paper,a masterslave method based multi-freedom constraints is proposed to impose essential boundary conditions and interfacial displacement constraints in modelling mechanical behaviour of composite materials using spH *** proposed methodology enforces the above constraints more accurately and requires only smaller condition number for system stiffness matrix than the procedures based on typical penalty function approach.A minimum cut-off value-based error criteria is employed to improve the computational efficiency of the proposed *** addition,the proposed method is further enhanced by adopting a modified numerical interpolation scheme along the boundary to increase the accuracy and computational *** numerical examples demonstrate that the proposed master-slave approach yields better accuracy in enforcing displacement constraints and requires approximately the same computational time as that of penalty method.

关键词： particulate composites spH Essential boundary condition Multi-point constraints Master-slave method

Construction of 2D/2D Ti_(3)C_(2)T_(x)MXene/Cds heterojunction with photothermal effect for efficient photocatalytic hydrogen production

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journal of Materials science & Technology 2024年第4期171卷 1-9页

作者： T.Y.Huang z.Yang s.Y.Yang z.H.Dai Y.j.Liu j.H.Liao G.Y.zhong z.j.Xie Y.p.Fang s.s.zhang Key Laboratory for Biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China school of physics and Optoelectronics South China University of TechnologyGuangzhou 510640China school of Chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic *** photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor ***,a novel stable Ti_(3)C_(2)T_(x)MXene/Cds heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)Cds nanosheets on 2D MXene interface via a solvothermal *** exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous *** unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the ***,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of *** irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of Cds *** study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure Heterostructure photothermal effect photocatalyst Hydrogen evolution

structure, formation, and decay of ■NN system by Faddeev-AGs calculations

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Chinese physics C 2019年第6期43卷 21-31页

作者： s.Marri s.z.Kalantari j.Esmaili Department of physics Isfahan University of TechnologyIsfahan 84156-83111Iran Department of physics Faculty of Basic Sciences Shahrekord UniversityShahrekord115Iran

The Faddeev AGs equations for the coupled-channels ■NN-πΣN system with quantum numbers I=1/2 and s=0 are solved. Using separable potentials for the ■N-πΣ interaction, we calculate the transition probability for the(YK)I=0 + N→πΣN reaction. The possibility to observe the trace of the K-pp quasi-bound state in πΣN mass spectra was studied. Various types of chiral-based and phenomenological potentials are used to describe the ■N-πΣ interaction. Finally, we show that we can observe the signature of the K-pp quasi-bound state in the mass spectra, as well as the trace of branch points in the observables.

关键词： Faddeev method ■N interaction K^-pp system quasi-bound state

Cytogenetical Changes among polyembryonic(pEm)and Non-pEm Maize plants

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phyton-International journal of Experimental Botany 2021年第1期90卷 87-97页

作者： A.A.Román-Calzoncit F.Ramírez-Godina j.sánchez-Laureano A.C.Flores-Gallegos j.Espinoza-Velázquez R.Rodríguez-Herrera school of Chemistry Universidad Autónoma de Coahuila.Blvd.V.Carranza e Ing.JoséCárdenas V.s/n.Col.República Ote.C.P.25280.SaltilloCoahuilaMéxico plant Breeding Department Universidad Autónoma Agraria Antonio NarroBlvd.Antonio Narro 1923BuenavistaSaltilloMéxico

polyembryony in maize(pEm)contributes to improving the nutritional properties of the grain,as well as an increase in yield,since it generates multiple plants per seed,opening the possibility of developing new ***,it is unknown whether polyembryony in maize is the product of chromosomal *** on the above,in this research a cytogenetic study was proposed to verify if chromosomal abnormalities are related to the maize *** a meiotic study,maize genotypes with variable proportions of polyembryony(pEm),from the UA-IMM-BAp population and non-pEm(monoembryonic)maize were used,while for a mitosis analysis,30 families of maternal half-siblings(MHs)from two different populations with high polyembryony,denominated as BHp(brachytic,high polyembryony)and NHp(normal height,high polyembryony)were *** these genotypes were planted in the Buenavista Agricultural Experimental station-UAAAN at saltillo,Coahuila,*** frequency of pEm was estimated in all *** was found that the polyembryony occurs at frequencies from 34 to 66%in the D-02,BHp group,and from 13 to 21%in the segregating groups of the G3-0202 and *** squash technique was used for both cytogenetic *** meiotic irregularities in maize chromosomes were detected,such as irregular association of 10%of chromosomes in metaphase 1,and agglomeration of chromatin in 100%of the *** addition,pollen viability was estimated by the staining technique with 1%acetocarmine dye,and it was found that the polyembryonic ones have pollen viability of 100%.In meiosis in prophase,I sub-phase diakinesis,ten pairs of bivalents were confirmed,confirming 2n=20,both in non-pEm and pEm maize,corroborating mating,and balanced segregation,without the presence of univalent or *** the chromosomal count carried out in cells in mitosis,only in the BHp-200 polyembryonic family was registered two out of twenty triploid *** condition of ploidy is atypical in

关键词： zea mays irregular meiosis mitosis chromosomes chromatin polyploidy

Forging strength-ductility unity in a high entropy steel

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journal of Materials science & Technology 2022年第18期113卷 158-165页

作者： s.j.Tsianikas Y.Chen j.jeong s.zhang z.Xie school of Mechanical Engineering The University of AdelaideSA 5005Australia Centre for Advanced Thin Film Materials and Devices Faculty of Materials and EnergySouthwest UniversityChongqing 400715China Max-planck-Institut für Eisenforschung Max-Planck-Straße 1Düsseldorf 40237Germany

Fe_(72.4)Co_(13.9)Cr_(10.4)Mn_(2.7)B_(0.34)high entropy steel was prepared by magnetron *** alloy exhibits a high yield strength of 2.92±0.36 Gpa while achieving appreciable plasticity of 13.7±1.9%at the ultimate compressive strength(3.37±0.36 Gpa).The distribution of iron and chromium shows an un-usual,characteristic spinodal-like pattern at the nanometer scale,where compositions of Fe and Cr show strong anticorrelation and vary by as much as 20 at.%.The high strength is largely attributable to the compositional modulations,combined with fine grains with body-centered cubic(BCC)crystal structure,as well as grain boundary segregation of interstitial *** impressive plasticity is accommodated by the formation and operation of multiplanar,multicharacter dislocation slips,mediated by coherent in-terfaces,and controlled by shear *** excellent strength-ductility combination is thus enabled by a range of distinctive strengthening mechanisms,rendering the new alloy a potential candidate for safety-critical,load-bearing structural applications.

关键词： Deformation mechanisms Micromechanical testing Compositional fluctuations Body-centered cubic High entropy steel

Deciphering deformation mechanisms of hierarchical dual-phase CrCoNi coatings

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journal of Materials science & Technology 2020年第4期39卷 7-13页

作者： s.j.Tsianikas Y.Chen z.Xie school of Mechanical Engineering The University of AdelaideAdelaideSA5005Australia Centre for Advanced Thin Film Materials and Device Faculty of Materials and EnergySouthwest UniversityChongqing400715China school of Engineering Edith Cowan UniversityWA6027Australia

Hierarchical Cr Co Ni medium entropy alloy(MEA)thin films with a dual-phase face-centred cubic(FCC)and hexagonal closed-packed(HCp)nanostructure were prepared on M2 steel substrates by closed field unbalanced magnetron *** tests show an ultra-high hardness of 9.5 Gpa,attributable to large amounts of innate planar defects(i.e.,growth twins and stacking faults)impeding dislocation motion in the coatings.A deep analysis of undeformed and post-mortem samples reveals grain refinement as the dominant deformation mechanism in FCC dominated regions,while phase transformation and shear banding played major roles in regions occupied by HCp *** grain refinement was facilitated by twin/matrix lamellae,with dislocations piling up and arranging into interconnecting grain *** shear banding was accelerated by innate planar defects in the HCp phase due to a lack of slip *** particular interest is the observation of HCp→FCC phase transformation,which was catalysed by deformation-induced grain reorientation with innate stacking faults acting as embryos to grow the FCC *** results of this work suggest that multiple deformation pathways could be activated in Cr Co Ni coatings with assistance of growth defects,thereby imparting these technically important coatings appreciable ductility.

关键词： Medium entropy alloys sputter deposition Grain refinement shear banding phase transformation