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communications in Theoretical Physics 2021年第12期73卷 78-85页

作者： Yu-Han Ma c P sun Hui Dong Graduate School of china Academy of Engineering Physics Beijing 100193China Beijing computational Science Research center Beijing 100193China

The efficiency at the maximum power(EMP)for finite-time carnot engines established with the low-dissipation model,relies significantly on the assumption of the inverse proportion scaling of the irreversible entropy generationΔS^(ir)on the operation timeτ,i.e.ΔS^(ir)∝1/τ.The optimal operation time of the finite-time isothermal process for EMP has to be within the valid regime of the inverse proportion ***,such consistency was not tested due to the unknown coefficient of the 1/τ-*** this paper,we reveal that the optimization of the finite-time two-level atomic carnot engines with the low-dissipation model is consistent only in the regime ofη_(c)c)is the carnot efficiency,andδis the compression ratio in energy level difference of the heat engine *** the large-η_(c)regime,the operation time for EMP obtained with the low-dissipation model is not within the valid regime of the 1/τ-scaling,and the exact EMP of the engine is found to surpass the well-known boundη_(c)=η_(c)/(2-η_(c)).

关键词： finite-time thermodynamics low-dissipation model quantum heat engine efficiency at maximum power irreversible entropy generation

Design of double negativity elastic metamaterial

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International Journal of Smart and Nano Materials 2015年第1期6卷 61-72页

作者： Y.c.Su c.T.sun School of Aeronautics and Astronautics Purdue UniversityWest Lafay

A metamaterial model that possesses simultaneously negative effective mass density and negative effective Young’s modulus is proposed in this *** curves and dynamic responses of the model are *** the double negative frequency region,it is demonstrated that the phase velocity is *** addition,it was found that the band gap region of the metamaterial can be predicted accurately by taking parts of single-unit cell to analyze the steady-state *** design is also fabricated by a 3D printer.

关键词： acoustic metamaterial double negativity local resonance negative mass negative modulus

Estrogen enhances the functions of cD4^(+)cD25^(+)Foxp3^(+) regulatory T cells that suppress osteoclast differentiation and bone resorption in vitro

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cellular & Molecular Immunology 2011年第1期8卷 50-58页

作者： cY Luo L Wang c sun DJ Li Laboratory for Reproductive Immunology Hospital and Institute of Obstetrics and GynecologyFudan University Shanghai Medical CollegeShanghaiChina Jiangsu Province Hospital the First Affiliated Hospital with Nanjing Medical UniversityNanjingChina Department of Obstetrics and Gynecology Affiliated HospitalHainan Medical CollegeHaikouChina

cross-talk has been shown to occur between the immune system and bone metabolism *** the present study,we investigated the impact of cD4^(+)cD25^(+)Foxp3^(+) regulatory T(Treg)cells on osteoclastogenesis and bone *** cells that were isolated and purified from peripheral blood mononuclear cells(PBMcs)of healthy adults inhibited both the differentiation of osteoclasts(Ocs)from human embryo bone marrow cells(BMcs)and the pit formation in a dose-dependent *** cell cocultures,the production levels of both interleukin-10(IL-10)and transforming growth factor-beta 1(TGF-β1)were proportionally upregulated as the ratio of Treg cells to BMcs was increased,and the inhibition of Oc differentiation and bone resorption by Treg cells was completely reversed by anti-IL-10 and anti-TGF-β1 *** of BMc and Treg cell cocultures with 17β-estradiol(E2)at concentrations between 10^(-7) and 10^(-9) mol/l suppressed Oc differentiation and bone resorption more efficiently than it did in cultures of BMcs alone;this enhanced suppression occurred via the stimulation of Treg cell IL-10 and TGF-b1 *** data suggest that Treg cells suppress Oc differentiation and bone resorption by secreting IL-10 and TGF-β1.E2 enhances the suppressive effects of Treg cells on Oc differentiation and bone resorption by stimulating IL-10 and TGF-β1 secretion from these ***,Treg cell-derived IL-10 and TGF-b1 are likely involved in the regulation of E2 on bone metabolism and represent potential therapeutic targets for the treatment of postmenopausal osteoporosis(PMO).

关键词： bone resorption osteoclast PMO regulatory T cells

MODIFIcATION OF SURFAcE MEcHANIcAL PROPERTIES OF POLYcARBONATE BY B^+ AND O^+ IONS IMPLANTATION

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Acta Metallurgica Sinica(English Letters) 2002年第1期15卷 33-38页

作者： S.D. Yao c. sun S.Q. Zhou c.c. sun Y.H. Lu L. Huang A. Vantomme Q. Zhao G. Langouche School of Physics Peking University Beijing 100871 China college of chemistry and Molecular Enginearing Peking University Beijing 100871 China Instituut Voor Kern-en Stralingsfysika University of Leuven B-3001 Leuven Belgium

By implanting B+ and O+ ions respectively into polycarbonate (Pc) plates, the surface mechanical properties of Pc have been improved. Measurement by Nano Indenter II showed that the hardness of samples increased 7-25 times than that before implantation; and the modulus of elasticity raised 2-5 times. The wear-resistance was tested by ball crusher; the width and depth of the wear-streak decreased by 1/3-1/2 or even more. The structure, deformation and appearance were analyzed by using Micro-FTIR Spectra, EScA method and the steps instrument. These analyses showed that the structure of Pc had been modified: a series of new cross-linking yielded, it depends on the Linear Energy Transition (LET) of implanted ions in the high polymer compounds.

关键词： polycarbonate ion implantation surface modification

Improvement of coercivity and corrosion Resistance of Nd-Fe-B Sintered Magnets with cu Nano-particles Doping

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Journal of Materials Science & Technology 2012年第10期28卷 927-930页

作者： c.sun W.Q.Liu H.sun M.Yue X.F.Yi J.W.chen college of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China Earth-panda Advance Magnetic Material co. Ltd.Anhui 231500China

Nd-Fe-B permanent magnets with a small amount of cu nano-particles doping have been prepared by con-ventional sintered method. Effects of cu content on magnetic properties, corrosion resistance, and oxidation properties of the magnets have been studied. It shows that the coercivity rises gradually, while the remanence decreases simultaneously with increasing cu doping amount. Microstructure observation reveals that cu ele- ment enriches mainly the Nd-rich phase. Autoclave test results show that the corrosion rate of the magnets decreases with increasing cu content. After oxidation, the maximum energy product loss of the magnets with 0 and 0.2 wt% cu nano-particles doping are 6.13% and 0.g9%, respectively. Therefore, it is concluded that cu nano-particles doping is a promising way to enhance the coercivity and corrosion resistance of sintered Nd-Fe-B magnets.

关键词： Nd-Fe-B cu nano-particles coercivity corrosion resistance Oxidation

Microstructural evolution and mechanical properties of NicrAlYSi+NiAl/cBN abrasive coating coated superalloy during cyclic oxidation

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Journal of Materials Science & Technology 2021年第12期71卷 44-54页

作者： Y.D.Liu J.sun W.Li W.S.Gu Z.L.Pei J.Gong c.sun School of Materials Science and Engineering University of Science and Technology of China72 Wenhua RoadShenyang 110016China Institute of Metal Research Chinese Academy of Sciences72 Wenhua RoadShenyang 110016China Advanced Research Institute for Multidisciplinary Science Qilu University of Technology(Shandong Academy of Sciences)3501 Daxue RoadJinan 250353China

cyclic oxidation behavior of Ni cr Al YSi+Ni Al/c BN abrasive coating at 900°c and the mechanical properties of the coating-substrate system were *** indicated that elemental interdiffusion occurred between the coating and substrate,which caused the formation of interdiffusion zone(IDZ)and secondary reaction zone(SRZ)during aluminization,while their compositions and structures changed with *** N interfacial layer formed at c BN/metallic matrix interface during aluminization,while it transformed into multilayer oxides during *** to the microstructural evolution of these interfaces,the fracture behavior and bending toughness of the system changed greatly during three-point bending ***,the damage mechanisms were discussed.

关键词： Abrasive coating cyclic oxidation TEM Interface Superalloy

Immune receptor signaling： from ubiquitination to NF-κB ctivation

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cellular & Molecular Immunology 2012年第2期9卷 97-98页

作者： Dr S-c sun Department of Immunology The University of Texas MD Anderson cancer center Houston TX 77030 USA

The immune system functions as a dynamic and sophisticated network that ensures efficient response to foreign antigens and tolerance to self-tissues） The function of the immune system relies on signal transduction that connects immune cells to the extracellular environment and mediates communication among the different types of immune cells. Among the well-characterized immunoregulatory sienaling pathways is that which leads to the activation of nuclear

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Hot corrosion Behavior of Hf-Doped NiAl coating in the Mixed Salt of Na_(2)SO_(4)+K_(2)SO_(4)at 900℃

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Acta Metallurgica Sinica(English Letters) 2023年第9期36卷 1409-1420页

作者： W.L.Zhang W.Li L.B.Fu X.Peng J.sun S.M.Jiang J.Gong c.sun Shi-changxu Innovation center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China Advanced Research Institute for Multidisciplinary Science Qilu University of Technology(Shandong Academy of Sciences)Jinan250353China

The hot corrosion behavior of the NiAl coating and the 5Hf-NiAl coating induced by mixed salt at 900℃was *** with the NiAl coating,the 5Hf-NiAl coating exhibited superior hot corrosion resistance because the addition of Hf promoted the formation of protective oxide scale and reduced the growth rate of oxide ***,internal sulfides were not present in the 5Hf-NiAl coating after hot corrosion for 140 *** exhibited different distribution in the two coatings since the addition of Hf changed the hot corrosion process of the *** and Ti in the 5Hf-NiAl coating trapped and captured sulfur,preventing the penetration of sulfur into the *** hot corrosion mechanism of the two coating and the effects of Hf on this process were discussed in this work.

关键词： Hot corrosion Hafnium Oxide scale Titanium Sulfide

EFFEcTS OF HEAT TREATMENT ON THE MIcROSTRUcTURE OF cu-Zn-Al (RE) SHAPE MEMORY ALLOYS

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Acta Metallurgica Sinica(English Letters) 2001年第4期14卷 257-262页

作者： N.c. Si and S.c. sun Material Science and Engineering School, Jiangsu University of Science and Technology, Jiangsu 212013, china Sch. of Mat. Sci. and Eng. Jiangsu Univ. of Sci. and Technol. Jiangsu 212013 China

The effects of heat treatment on the cu-Zn-Al shape memory alloys with mixed REwere researched with the help of X-ray diffraction and transmission electron micro-scope (TEM).The results show that the shape memory alloys with martensite can beproduced by adding mixed RE and heat treatment processes holding at 820c -880cfor 15min,quenching into oil,aging at 150c for 15min,and then holding in waterat 50c for *** alloys have the lowest transformation thermal *** the four experimental heat treatment processes the gradationally quenchingmakes the alloy have the highest transformation temperature and quenching into oilor water at room temperature makes the alloy have the largest thermal ***-crostructure examination shows that aging at 2000c could destroy the substructuresin lathy martensites in the alloy and form a lot of dislocations,and aging at 250℃could cause the bainite transformation in the alloy.

关键词： cu-Zn-Al (RE) heat treatment transformation temperature thermoelastic martensite

Oxidation Performance and Interdiffusion Behaviour of two McrAlY coatings on a Fourth-Generation Single-crystal Superalloy

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Acta Metallurgica Sinica(English Letters) 2022年第4期35卷 679-692页

作者： K.J.Tan J.J.Liang X.G.Wang X.P.Tao J.Gong c.sun Y.Z.Zhou X.F.sun Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

The oxidation behaviour of a fourth-generation single-crystal superalloy without coating and with two types of McrAlY coatings at 1140℃was *** results showed that both coatings greatly improved the oxidation resistance of the superalloy,and the addition of Hf further improved the oxidation resistance by pinning the oxide layer into the *** and after oxidation,obvious cr and Al interdiffusion was *** cr diffusion induces the precipitation of a topologically close-packed phase,while the diffusion of Al affects the structure of theγ/γ’phase,the solubility of refractory elements,and the formation of an interdiffusion zone.

关键词： Superalloys Metal coatings Oxidation Electron probe microanalyser(EPMA) Element diffusion