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Modeling mechanical behaviors of composites with various ratios of matrixeinclusion properties using movable cellular automaton method

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Defence Technology（防务技术） 2015年第1期11卷 18-34页

作者： A.Yu.sMOLIN E.V.sHILKO s.V.AsTAFUROV I.s.KONOVALENKO s.P.BUYAKOVA s.G.PsAKHIE Institute of strength Physics and Materials science sB RAs Tomsk state University Institute of High Technology Physics Tomsk Polytechnic University skolkovo Institute of science and Technology

Two classes of composite materials are considered: classical metaleceramic composites with reinforcing hard inclusions as well as hard ceramics matrix with soft gel inclusions. Movable cellular automaton method is used for modeling the mechanical behaviors of such different heterogeneous materials. The method is based on particle approach and may be considered as a kind of discrete element method. The main feature of the method is the use of many-body forces of inter-element interaction within the formalism of simply deformable element approximation. It was shown that the strength of reinforcing particles and the width of particle-binder interphase boundaries had determining influence on the service characteristics of metaleceramic composite. In particular, the increasing of strength of carbide inclusions may lead to significant increase in the strength and ultimate strain of composite material. On the example of porous zirconia ceramics it was shown that the change in the mechanical properties of pore surface leads to the corresponding change in effective elastic modulus and strength limit of the ceramic sample. The less is the pore size, the more is this effect. The increase in the elastic properties of pore surface of ceramics may reduce its fracture energy.

关键词： Composites Metal ceramics Zirconia ceramics Gel Modeling Movable cellular automata Many-body interaction

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

Risk of pacemaker implantation after femur fracture in patients with and without a history syncope: a Danish nationwide registry-based follow-up study

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Journal of Geriatric Cardiology 2022年第9期19卷 712-718页

作者： sara LK Clemmensen Kristian Kragholm Bhupendar Tayal Christian Torp-Pedersen søren Kold Peter søgaard sam Riahi Department of Cardiology Aalborg University HospitalAalborgDenmark Unit of Clinical Biostatistics and Epi-demiology Aalborg University HospitalAalborgDenmark Department of Clinical Epidemiology Aalborg University HospitalAalborgDenmark Department of Orthopedics Aalborg University HospitalAalborgDenmark Depart-ment of Clinical Institute Aalborg University HospitalAalborgDenmark

BACKGROUND It has previously been described that fall-associated injuries including fractures are commonly observed among patients with ***,knowledge on the risk of pacemaker implantation after admission due to femur fracture from large population-based epidemiologic data is ***,we investigated the risk of pacemaker implanta-tion following femur fracture in patients with and without a history of previous *** All patients with femur fracture between 2005-2017 were identified using the Danish Nationwide Patient *** these,patients already having a pacemaker were *** outcome was one-year risk of pacemaker implanta-tion and secondary outcome was one-year all-cause *** logistic regression was used to obtain absolute and relative risks of the study endpoint in relation to patients with versus without history of syncope and standardized to the age,sex,selected comorbidity and pharmacotherapy distribution of all *** Of 93,093 patients with femur fracture,5508(5.9%)had a history of syncope within five *** with prior syn-cope were slightly older(84 vs.83 years),more often male(33.6%vs.29.4%),and had more often comorbidities relative to those without history of ***-cause mortality was significantly higher among those with previous history of syncope com-pared to those without previous syncope(29.9%vs.28.6%,P=0.021).The relative mortality risk was 1.05(95%CI:1.01−1.09,P=0.021).A total of 695(0.8%)patients underwent pacemaker implantation within 5 years following femur fracture,and a signific-antly higher proportion of patients with syncope had a pacemaker implanted within one year(1.6%vs.0.7%,Psk,2.01[95%CI:1.55−2.46]).CONCLUsIONs In patients with femur fracture,a history of syncope was significantly associated with a higher one-year risk of pacemaker implantation.

关键词： patients syncope injuries

Interpretable modeling of metallurgical responses for an industrial coal column flotation circuit by XGBoost and sHAP-A “conscious-lab” development

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International Journal of Mining science and Technology 2021年第6期31卷 1135-1144页

作者： s.Chehreh Chelgani H.Nasiri M.Alidokht Minerals and Metallurgical Engineering Dept.of CivilEnvironmental and Natural Resources EngineeringLuleåUniversity of TechnologySE-97187 LuleåSweden Department of Computer Engineering Amirkabir University of TechnologyTehranIran Tabas Parvardeh Coal Company(TPCCO) BirjandIran

surprisingly,no investigation has been explored relationships between operating variables and metallurgical responses of coal column flotation(CF) circuits based on industrial databases for under operation *** a novel approach,this study implemented a conscious-lab "CL" for filling this *** this approach,for developing the CL dedicated to an industrial CF circuit,sHapley Additive explanations(sHAP) and extreme gradient boosting(XGBoost) were powerful unique machine learning systems for the first time *** explainable artificial intelligence models could effectively convert the dataset to a basis that improves human capabilities for better understanding,reasoning,and planning the *** could provide precise multivariable correlation assessments between the CF dataset by using the Tabas Parvadeh coal plant(Kerman,Iran),and showed the importance of solid percentage and washing water on the metallurgical responses of the coal CF *** could predict metallurgical responses(R-square> 0.88) based on operating variables that showed quite higher accuracy than typical modeling methods(Random Forest and support vector regression).

关键词： sHAP XGBoost Explainable AI Coal flotation separation efficiency

Nonlinear free vibrations of porous composite microplates incorporating various microstructural-dependent strain gradient tensors

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Applied Mathematics and Mechanics(English Edition) 2022年第6期43卷 825-844页

作者： Duquan ZUO B.sAFAEI s.sAHMANI Guoling MA Aviation Engineering College Civil Aviation Flight University of ChinaGuanghan 618307Sichuan ProvinceChina Chongqing Engineering Research Center for Advanced Intelligent Manufacturing Technology Chongqing Three Gorges UniversityChongqing 404100China Department of Mechanical Engineering Eastern Mediterranean UniversityFamagusta 99628North Cyprus via Mersin 10Turkey school of science and Technology The University of GeorgiaTbilisi 0171Georgia

The main objective of the present numerical analysis is to predict the nonlinear frequency ratios associated with the nonlinear free vibration response of porous composite plates at microscale in the presence of different microstructural gradient *** achieve this end,by taking cubic-type elements into account,isogeometric models of porous composite microplates are obtained with and without a central cutout and relevant to various porosity patterns of distribution along the plate *** established unconventional models have the capability to capture the effects of various unconventional gradient tensors continuity on the basis of a refined shear deformable plate *** the simply supported microsized uniform porous functionally graded material(UPFGM)plate having the oscillation amplitude equal to the plate thickness,it is revealed that the rotation gradient tensor causes to reduce the frequency ratio about 0.73%,the dilatation gradient tensor causes to reduce it about 1.93%,and the deviatoric stretch gradient tensor leads to a decrease of it about 5.19%.On the other hand,for the clamped microsized U-PFGM plate having the oscillation amplitude equal to the plate thickness,these percentages are equal to 0.62%,1.64%,and 4.40%,***,it is found that by changing the boundary conditions from clamped to simply supported,the effect of microsize on the reduction of frequency ratio decreases a bit.

关键词： size dependency isogeometric approach nonlinear dynamics geometric approximation micromechanics

Inhibition of Wnt signaling by Frizzled7 antibody-coated nanoshells sensitizes triple-negative breast cancer cells to the autophagy regulator chloroquine

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Nano Research 2020年第6期13卷 1693-1703页

作者： Jianxin Wang Megan N.Dang Emily s.Day Department of Biomedical Engineering University of DelawareNewarkDE19716USA Department of Materials science and Engineering University of DelawareNewarkDE19716USA Helen F.Graham Cancer Center&Research Institute NewarkDE19713USA

Nano Research volume 13,pages1693–1703(2020)Cite this article 137 Accesses 6 Altmetric Metrics details Abstract Despite improvements in our understanding of the biology behind triple-negative breast cancer(TNBC),it remains a devastating disease due to lack of an effective targeted *** Wnt signaling is a promising strategy to combat TNBC because Wnt signaling drives TNBC progression,chemoresistance,and ***,Wnt inhibition can lead to upregulation of autophagy,which confers therapeutic *** provides an opportunity for combination therapy,as autophagy inhibitors applied concurrently with Wnt inhibitors could increase treatment ***,we applied the autophagy inhibitor chloroquine(CQ)to TNBC cells in combination with Frizzled7 antibody-coated nanoshells(FZD7-Ns)that suppress Wnt signaling by blocking Wnt ligand/FZD7 receptor interactions,and evaluated this dual treatment in *** found that FZD7-Ns can inhibit Axin2 and CyclinD1,two targets of canonical Wnt signaling,and increase the expression of LC3,an autophagy *** FZD7-Ns and CQ are applied together,they reduce the expression of several stemness genes in TNBC cells,leading to inhibition of TNBC cell migration and ***,co-delivery of FZD7-Ns and CQ is more effective than either therapy alone or the combination of CQ with free FZD7 *** demonstrates that the nanocarrier design is important to its therapeutic ***,these findings indicate that combined regulation of Wnt signaling and autophagy by FZD7-Ns and CQ is a promising strategy to combat TNBC.

关键词： nanomedicine nanoparticles combination therapy antibody delivery cancer stem cells

Hybrid nanomaterial flow and heat transport in a stretchable convergent/divergent channel:a Darcy-Forchheimer model

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Applied Mathematics and Mechanics(English Edition) 2020年第5期41卷 699-710页

作者： G.K.RAMEsH s.A.sHEHZAD I.TLILI Department of Mathematics K.L.E Society’s J.T.CollegeGadag 582101KarnatakaIndia Department of Mathematics COMSATS University IslamabadSahiwal 57000Pakistan Department for Management of science and Technology Development Ton Duc Thang UniversityHo Chi Minh City 758307Vietnam Faculty of Applied sciences Ton Duc Thang UniversityHo Chi Minh City 758307Vietnam

The flow behavior in non-parallel walls is an important factor of any physical model including cavity flow and canals, which is applicable for diverging/converging channel. The present communication explains that the flow of the hybrid nanomaterial subjected to the convergent/divergent channel has non-parallel walls. It is assumed that the hybrid nanomaterial movement is in the porous region. A Darcy-Forchheimer medium of porosity is considered to interpret the porosity features. A useful similarity function is adopted to get the strong ordinary coupled equations. Numerical solutions are achieved through the Runge-Kutta-Fehlberg(RKF) fourth-fifth order method, and they are validated with the existing results. Physical nature of the involving constraints is reported with the help of plots. It is explored that the velocity of divergent channel decreases, and convergent channel enhances for the higher solid volume faction. Further, the presence of inertia coefficient and porosity parameter amplifies the velocity at the wall.

关键词： hybrid nanoliquid channel Darcy-Forchheimer flow stretching wall numerical solution

Trace Elements and sr, Nd Isotope Geochemistry of the Lajimiao Norite-Gabbro from the North Qinling Belt

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Acta Geologica sinica(English Edition) 1994年第2期68卷 137-151页

作者： s.R.Hart Department of Geology and Geopphysics Woods Hole Oceanographic InstituteWoods

The Lajimiao norite-gabbro complex, as a part of the ophiolites on the southern side of the North Qinling belt, consists of gabbro and norite-gabbro. They were derived from different magma series: the gabbro was derived from tholeiitic magma series with higher TiO2, REE abundance and Fe3+/Fe2+ ratio ; norite-gabbro was derived from calc-alkali magma series with lower TiO2, Fe3+/Fe2+ ratio and REE abundance and much lower HREE abundance, which suggests that the source of the norite-gabbro magma was deeper and controlled by eclogite facies. Geochemical characteristics of both plutonic rocks are similar to those of island-arc basalts, such as relatively high contents of Ba, Pb and sr and relatively low contents of Nb, Zr and N *** sr, Nd isotopic characteristics of the Lajimiao norite-gabbro complex are similar to those of ophiolites. Its εNd values are constant, about+2; whereas εst values have wide variation from - 6.4 to +31.2 and positively correlate with Na2O, H2O+ and CO2 contents and the Fe3+/Fe2+ ratio. The εNd- Nd/Th, εNd- La/Nb and εNd-Ba/Nb diagrams clearly show that there were significant components of terrigenous sediments in the mantle source of the Lajimiao norite-gabbro complex. It suggests that large amount of sediments had been carried into the mantle by the subducted ancient Qinling sea plate during the Palaeozoic.

关键词： trace element sr/Nd isotopes norite-gabbro Lajimiao North Qinling

Interfacial fracture analysis for a two-dimensional decagonal quasi-crystal coating layer structure

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Applied Mathematics and Mechanics(English Edition) 2021年第11期42卷 1633-1648页

作者： Minghao ZHAO Cuiying FAN C.s.LU Huayang DANG school of Mechanics and safety Engineering Zhengzhou UniversityZhengzhou 450001China school of Mechanical Engineering Zhengzhou UniversityZhengzhou 450001China school of Civil and Mechanical Engineering Curtin UniversityWestern Australia 6845Australia

The interface crack problems in the two-dimensional(2D)decagonal quasicrystal(QC)coating are theoretically and numerically investigated with a displacement discontinuity *** 2D general solution is obtained based on the potential *** analogy method is proposed based on the relationship between the general solutions for 2D decagonal and one-dimensional(1D)hexagonal *** to the analogy method,the fundamental solutions of concentrated point phonon displacement discontinuities are obtained on the *** using the superposition principle,the hypersingular boundary integral-differential equations in terms of displacement discontinuities are determined for a line interface ***,Green’s functions are found for uniform displacement discontinuities on a line *** oscillatory singularity near a crack tip is eliminated by adopting the Gaussian distribution to approximate the delta *** stress intensity factors(sIFs)with ordinary singularity and the energy release rate(ERR)are ***,a boundary element method is put forward to investigate the effects of different factors on the fracture.

关键词： two-dimensional(2D)decagonal quasi-crystal(QC)coating interface crack analogy method displacement discontinuity stress intensity factor(sIF) energy release rate(ERR)