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^3PF2 neutron superfluidity in neutron stars and three-body force effect

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Chinese Physics B 2008年第9期17卷 3289-3293页

作者：崔常喜左维 h.j.Schulze Institute of Modern Physics Chinese Academy of Sciences INFN Sezione di Catania

We investigate the ^3PF2 neutron superfluidity in h-stable neutron star matter and neutron stars by using the BCS theory and the Brueckner-hartree-Fock approach. We adopt the Argonne V18 potential supplemented with a microscopic three-body force as the realistic nucleon-nucleon interaction. We have concentrated on studying the threebody force effect on the ^3PF2 neutron pairing gap. It is found that the three-body force effect is to enhance remarkably the ^3PF2 neutron superfluidity in neutron star matter and neutron stars.

关键词： ^3PF2 superfluidity neutron star three-body force Brueckner-hartree-Fock approach

hardness-thermal stability synergy in nanograined Ni and Ni alloys:Superposition of nanotwin and low-energy columnar boundary

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journal of Materials Science & Technology 2023年第6期137卷 123-131页

作者： F.h.Duan Y.Lin Q.Li j.h.Luan j.Lu j.Pan Y.Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Laboratory of Nanomaterials&Nanomechanics Department of Mechanical EngineeringCity University of Hong KongHong KongChina State Key Laboratory of Material Processing and Die&Mould Technology and School of Materials Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China Department of Materials Science and Engineering City University of Hong KongHong KongChina Centre for Advanced Structural Materials Greater Bay Joint DivisionShenyang National Laboratory for Materials ScienceCity University of Hong Kong Shenzhen Research InstituteShenzhen 518057China City U-Shenzhen Futian Research Institute Shenzhen 518045China

Refining grains into nanoscale can significantly strengthen and harden metallic materials;however,nanograined metals generally exhibit low thermal stability,hindering their practical *** this work,we exploit the superposition of the contribution of nanotwins,low-angle grain boundaries,and microalloying to tailor superior combinations of high hardness and good thermal stability in Ni and Ni *** the nanotwinned Ni having a twin thickness of∼2.9 nm and grain size of 28 nm,it exhibits a hardness over 8.0 GPa and an onset coarsening temperature of 623 K,both of which are well above those of nanograined ***/Mo microalloying can further improve the onset coarsening temperature to 773 K without comprising *** analyses reveal that high hardness is achieved via strengthen-ing offered by extremely fine ***,the superior thermal stability is mainly ascribed to the low driving force for grain growth induced by the low-angle columnar boundary architecture and to the additional pinning effect on the migration of twin/columnar boundaries provided by minor Re/Mo *** present work not only reveals a family of nanotwinned metals possessing the combination of ultra-high hardness and high thermal stability but also provides a strategy for tailoring properties of metallic materials by pairing low-angle grain boundaries and twin boundaries.

关键词： Nanotwin Thermal stability hardness Low-angle grain boundary Microalloying

Macroscopic and microscopic mechanical behaviors of climbing tendrils

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Acta Mechanica Sinica 2019年第3期35卷 702-710页

作者： Q.Guo j.j.Dong Y.Liu X.h.Xu Q.h.Qin j.S.Wang Tianjin Key Laboratory of Modern Engineering Mechanics Department of MechanicsTianjin UniversityTianjin 300054China State Key Laboratory of Nonlinear Mechanics (LNM) Institute of MechanicsChinese Academy of ScienceBeijing 100080China Research School of Engineering Australian National UniversityCanberraACT 2601Australia

Tendril-bearing climbing plants must recur to the tendril helices with chiral perversion or dual chirality for climbing and to obtain sun exposure. Despite researchers' prolonged fascination with climbing tendrils since Darwin's time and even earlier, why the soft and slender tendrils can bear heavy loads such as the self-weight of a plant or additional load caused by rain remains elusive. In this paper, we take towel gourd tendrils as an example and investigate the macroscopic and microscopic mechanical behaviors of tendrils through experiments and simulations. Our study indicates that the tendril filament exhibits rubber-like hyperelastic behaviors and can particularly endure large elongation, which is mainly attributed to the superelasticity of the cellulose fibril helix contained in the cell wall. Combination of the tendril helical structure with dual chirality or chiral perversion at a macroscale and a cellulose filament helix at a subcellular level creates superior elasticity for biological species relying on support and climbing. This study provides deep insight into the structure-property relationship of climbing tendrils, and the relationship is useful for the bioinspired design of composite systems with superior elasticity.

关键词： Climbing tendril Mechanical behaviors Structure-property relationship Large elongation

Biological transformation,kinetics and dose-response assessments of bound musk ketone hemoglobin adducts in rainbow trout as biomarkers of environmental exposure

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journal of Environmental Sciences 2008年第7期20卷 878-884页

作者： M A Mottaleb j h Zimmerman T W Moy Department of Chemistry and Biochemistry Baylor UniversityP.O.Box 97348WacoTX 76798USA. U.S.Environmental Protection Agency National Exposure Research LaboratoryEnvironmental Sciences Division944 East Harmon AveLas VegasNV 89119USA

Low levels (ng/g) of musk ketone (MK),used as a fragrance additive in the formulation of personal care products,are frequently detected in the water and other ***,aquatic organisms can be continuously exposed to *** this study,kinetics and dose-response assessments of 2-amino-MK (AMK) metabolite,bound to cysteine-hemoglobin (hb) in rainbow trout,formed by enzymatic nitro-reduction of MK have been *** were exposed to a single exposure of 0.010,0.030,0.10,and 0.30 mg MK/g ***...

关键词： biotransformation kinetics hemoglobin adducts dose-response nitro musks biomarker fish

The hot compressive deformation behavior of cast Mg-Gd-Y-Zn-Zr alloys with and without LPSO phase in their initial microstructures

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journal of Magnesium and Alloys 2022年第10期10卷 2901-2917页

作者： h.T.jeong W.j.Kim Departmentof Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

Samples of Mg-8.2Gd-3.8Y-1.1Zn-0.4Zr alloy with and without an intragranular lamellae-shaped long period stacking ordered(LPSO)phase were prepared through heat treatment and a series of hot compression tests on these materials were conducted to examine and evaluate the influence of LPSO on the hot compressive deformation behavior and deformation mechanisms at a given alloy *** values of activation energy for plastic flow(Qc)of the solution treated(without LPSO phase)and annealed alloys(with intragranular LPSO phase)were larger than that for pure Mg,indicating that the presence of a high amount of rare earth(RE)elements and LPSO in the Mg matrix significantly increases *** Qcvalue of the annealed alloy was larger than that of the solution treated alloy at all the strain levels(223.3 vs.195.5 k j/mol in average)and the largest difference in Qcbetween the two alloys was recorded at the smallest strain of 0.1 where precipitation of LPSO during deformation was limited in the solution treated *** observations imply that the formation of LPSO phase out of the RE-rich solid solution matrix during deformation increases Qc,but the increment is not so *** of the hot compressive data of the alloys with LPSO phase and the alloys with RE-rich solid solution matrix in literatures indicates the similarity of the effect of the LPSO and RE-rich solid solution matrix phases on Qcand high-temperature strength.

关键词： Magnesium alloys LPSO Deformation mechanism Dynamic recrystallization Activation energy for plastic flow Processing maps

Critical review of superplastic magnesium alloys with emphasis on tensile elongation behavior and deformation mechanisms

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journal of Magnesium and Alloys 2022年第5期10卷 1133-1153页

作者： h.T.jeong W.j.Kim Department of Materials Science and Engineering Hongik UniversitySangsu-dong 72-1 Mapo-guSeoul 121-791South Korea

The tensile elongation behavior and deformation mechanisms of superplastic Mg alloys and Mg composites were examined by extensively reviewing the literature published from the time of the first report on the superplasticity of Mg alloys to the present *** on the superplasticity of Mg alloys have been conducted mainly on Mg-Al-Zn(AZ)series alloys,Mg-Zn-Zr(ZK),Mg-Li and Mg-RE(rare earth)alloys,and in recent years,Mg-RE alloys have attracted the greatest *** effect of grain size and the type and amount of secondary phase particles on the superplasticity of Mg alloys was systematically examined and *** alloys processed by severe plastic deformation(SPD)and powder-metallurgy methods have smaller grain sizes and exhibit superior superplasticity compared to conventionally processed(by extrusion and rolling)Mg *** the AZ alloys,as the volume fraction of the Mg17Al12phase increases,smaller grains are obtained,and the low-temperature superplasticity(LTS)and high-strain-rate superplasticity(hSRS)characteristics become *** ZK60 alloy with finely dispersed Mg Zn2particles exhibits excellent LTS,while the Mg-RE alloys with a high fraction of thermally stable particles exhibit excellent ***-Li alloys can exhibit LTS even at room temperature due to the presence of a high-volume fraction of the body centered cubic(BCC)phase where atomic diffusivity is *** boundary diffusion-and lattice diffusion-controlled grain boundary sliding are found to operate as the dominant deformation mechanisms below~473 K and above~673 K,respectively,at small grain *** mechanism maps were constructed based on the analysis of the deformation behavior of superplastic Mg alloys,and from the maps,the critical conditions for achieving LTS,hSRS and simultaneous achievement of LTS and hRSR were calculated and proposed,and their importance was discussed.

关键词： Magnesium alloys Superplastic Grain size Secondary phase Grain boundary sliding

Composition design study of strong and ductile Mo-alloyed CoCrNi medium-entropy alloys

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材料科学技术（英文版） 2024年第19期186卷 37-47页

作者： j.X.Yan j.Y.Qin j.h.Liu h.Chen Y.h.huang M.Liu C.h.Xia F.Wang X.D.Cui j.B.Yang Z.F.Zhang School of Materials Science and Engineering Chongqing Jiaotong UniversityChongqing 400074China Southwest Technology and Engineering Research Institute Chongqing 400039China School of Materials Science and Engineering Chongqing Jiaotong UniversityChongqing 400074China Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

The assistance of alloying elements provides enormous opportunities for the discovery of high-performance face-centered cubic(FCC)medium-entropy alloys(MEAs).In this work,the influence of al-loying element Mo on the phase stability,stacking fault energy(SFE),deformation mechanisms,lattice distortion,and mechanical properties of(CoCrNi)100-xMox(0 ≤ x ≤ 10)MEAs was synthetically explored with the first-principles *** indicates that the FCC phase remains metastable at 0 K,and its stability degenerates with increasing Mo *** monotonous decrease of SFE is revealed with the rise of Mo content,which promotes the activation of stacking faults,deformation twinning,or martensitic *** Mo content also causes the aggravation of lattice distortion and thus triggers in-tense solid solution ***,the essential criterion for the composition design of FCC(CoCrNi)100-xMo MEAs with superior strength-ductility combination was established based on the syner-gistic effects between multiple deformation mechanisms and solid solution *** to the criterion,the optimal composition is predetermined as(CoCrNi)93Mo7 *** criterion is proved to be effective,and it can provide valuable inspiration for the development of alloying-element reinforced FCC multi-principal element alloys.

关键词： Medium-entropy alloys First-principles calculations Stacking-fault energy Solute strengthening Deformation twinning Mechanical properties

Ultrasonic-based surface patterning and interfacial reaction of ZrO_(2)ceramics

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journal of Materials Science & Technology 2023年第24期155卷 202-210页

作者： h.j. Dong Z.L. Li X.G.Song j.C. Feng S.j. Wei j.h. Fu Y. Shi State Key Laboratory of Advanced Welding and joining Harbin Institute of Technology Harbin 150001 China Shandong Provincial Key Lab of Special Welding Technology Harbin Institute of Technology at Weihai Weihai 264209 China

We demonstrate a process to achieve selective surface metallization of ZrO_(2)ceramics using ultrasound technology in atmospheric environments at 350℃,which bestows good weldability of ZrO_(2)to achieve rapid and reliable connections with other metals as well as ceramic *** challenge is that brazing or diffusion welding processes to accomplish metallurgical connections for ZrO_(2) typically require holding at elevated temperatures for minutes to hours,while the selective ultrasonic metallization process requires only a few seconds of processing without the application of covering films or solder *** this study,the selected Sn-2Ti alloy could effectively wet and spread on ZrO_(2)substrate under ultrasonication,and continuous interphase layers were rapidly formed in situ between ZrO_(2)and *** bonding strength for the ZrO_(2)/Sn-2Ti interface was well established with the highest shear strength of 37.1 MPa,and the fracture location occurred at the filler *** interfacial reaction layer thickened remarkably with the prolongation of sonication,accompanied by the partial crystallization of amorphous TiO and the formation of irregularly striped Ti_(11.31)Sn_(3)O_(10)nanocrystals.

关键词： Selective ultrasonic metallization Zirconia surface patterning Low temperature connection Sono-oxidation Interfacial reaction

Susceptibility of Large Wind Power Plants to Voltage Disturbances-Recommendations to Stakeholders

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journal of Modern Power Systems and Clean Energy 2022年第2期10卷 416-429页

作者： Roger Alves de Oliveira Math h.j.Bollen the Electric Power Engineering Group Lulea University of TechnologySkellefteaSweden

Sufficient fault ride-through(FRT)of large wind power plants(WPPs)is essential for the operation security of transmission *** majority of studies on FRT do not include all disturbances originating in the transmission system or the disturbances irrelevant to the operation *** on the knowledge of power quality,this paper provides a guide to stakeholders in different aspects of FRT for wind turbines(WTs)and *** paper details the characteristics of the most common disturbances originated in the transmission system,how they propagate to the WT terminals,and how they impact the dynamic behavior of a large *** paper shows that the details of the voltage disturbances,not only in the transmission system,but also at the WT terminals,should be taken into ***,a detailed representation or characterization of voltage dips is important for FRT studies,despite that the simplified models used in the literature are *** paper strongly recommends that distinct events and additional characteristics such as the phase-angle jump and oscillations in the transition segments should be considered in FRT analysis.

关键词： Wind power generation wind farm power quality fault ride-through(FRT) low voltage ride-through(LVRT)