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Dynamic response and plastic deformation behavior of Ti–5Al–2.5Sn ELI and Ti–8Al–1Mo–1V alloys under high-strain rate

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Rare Metals 2014年第2期33卷 127-133页

作者： Yan-Ling Wang Song-Xiao hui Rui liu Wen-Jun Ye Yang Yu Ravil Kayumov State Key Laboratory for Fabrication & Processing of Nonferrous Metals General Research Institute for Nonferrous Metals Department of Mechanical Engineering Sun Moon University

Split Hopkinson pressure bar test system was used to investigate the plastic deformation behavior and dynamic response character of a-type Ti–5Al–2.5Sn ELI and near a-type Ti–8Al–1Mo–1V titanium alloy when subjected to dynamic loading. In the present work, stress–strain curves at strain rate from 1.5 9 103to 5.0 9 103s-1were analyzed, and optical microscope（OM） was used to reveal adiabatic shearing behavior of recovered samples. Results show that both the two alloys manifest significant strain hardening effects. Critical damage strain rate of the two alloys is about 4.3 9 103s-1, under which the impact absorbs energy of Ti–5Al–2.5Sn ELI and Ti–8Al–1Mo–1V are 560 and 470 MJ m-3, respectively. Both of them fracture along the maximum shearing strength orientation, an angle of 45° to the compression axis. No adiabatic shear band（ASB） is found in Ti–5Al–2.5Sn ELI alloy, whereas several ASBs with different widths exist without regular direction in Ti–8Al–1Mo–1V alloy.

关键词： Titanium alloy Ti–5Al–2.5Sn ELI Ti–8Al– 1Mo–1V High-strain rate Adiabatic shear band

DNA-dependent activator of interferon-regulatory factors inhibits hepatitis B virus replication

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World Journal of Gastroenterology 2012年第22期18卷 2850-2858页

作者： Qi-Ying Chen Ying-hui liu Jian-Hua Li Ze-Kun Wang Jiang-Xia liu Zheng-Hong Yuan Key Laboratory of Medical Molecular Virology Ministry of Education and Ministry of Health Shanghai Medical College Fudan University Shanghai 200032 China Institutes of Biomedical Sciences Fudan University Shanghai 200032 China

AIM： To investigate whether DNA-dependent activator of interferon-regulatory factors （DAI） inhibits hepatitis B virus （HBV） replication and what the mechanism is. METHODS： After the human hepatoma cell line Huh7 was cotransfected with DAI and HBV expressing plas- mid, viral protein （HBV surface antigen and HBV e an- tigen） secretion was detected by enzyme-linked immu- nosorbent assay, and HBV RNA was analyzed by real- time polymerase chain reaction and Northern blotting, and viral DNA replicative intermediates were examined by Southern blotting. Interferon regulatory factor 3 （IRF3） phosphorylation and nuclear translocation were analyzed via Western blotting and immunofluorescence staining respectively. Nuclear factor-KB （NF-KB） activity induced by DAI was detected by immunofluorescence staining of P65 and dual luciferase reporter assay. Tran- swell co-culture experiment was performed in order to investigate whether the antiviral effects of DAI were dependent on the secreted cytokines. RESULTS： Viral protein secretion was significantly re- duced by 57% （P 〈 0.05）, and the level of total HBV RNA was reduced by 67% （P 〈 0.05）. The viral core particle-associated DNA was also dramatically down- regulated in DAI-expressing Huh7 cells. Analysis of involved signaling pathways revealed that activation of NF-KB signaling was essential for DAI to elicit antivi- ral response in Huh7 cells. When the NF-KB signaling pathway was blocked by a NF-KB signaling suppressor （I~：B^-SR）, the anti-HBV activity of DAI was remarkably abrogated. The inhibitory effect of DAI was indepen- dent of IRF3 signaling and secreted cytokines. CONCLUSION： This study demonstrates that DAI can inhibit HBV replication and the inhibitory effect is asso- ciated with activation of NF-KB but independent of IRF3 and secreted cytokines.

关键词： DNA-dependent activator of interferon regu-latory factor Antiviral activity Hepatitis B virus Nuclearfactor-~B Interferon regulatory factor-3

Changes of microstructure of different quench sensitivity 7,000 aluminum alloy after end quenching

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Rare Metals 2014年第3期33卷 270-275页

作者： Zhi-hui Zhang Bai-Qing Xiong Shu-Feng liu Bao-Hong Zhu Yu-Ting Zuo National Center of Analysis and Testing for Nonferrous Metals & Electronic Materials General Research Institute for Nonferrous Metals

The quench sensitivity and their influential factors of 7,021, 7,085, and 7,050 alloys were investigated by the end quenching test method and the measurement of electrical conductivity, hardness, and microstructure after aging. The results indicate that 7,050 alloy has the largest changes with hardness decreasing from HV 199 to HV 167,and electrical conductivity increases from 16.6 to18.2 MS m-1when the distance from quenched end increases from 2 to 100 mm. Alloys 7,085 and 7,021 have relatively smaller changes. According to the relationship between the hardness and electrical conductivity of a supersaturated solid solution, 7,050 alloy has higher quench sensitivity than 7,085 and 7,021 alloys. The microstructure of 7,050 alloy with higher major alloy element（Zn ？ Mg ？ Cu） addition and Cu element addition is mostly affected by the changes of distance from quenched end. In 7,050 alloy, the size of intragranular precipitates is from about 10-200 nm, and the（sub） grain boundary precipitates are about 20-300 nm. Alloy 7,085 with lower Cu content is moderately affected, while 7,021 is least affected. It is found that with the increase of distance from quenched end, quenched-induced precipitate preferentially nucleates and grows in the（sub） grain boundary and then on the pre-existing Al3 Zr particles.

关键词： 7,000 series aluminum alloy Quenchsensitivity Microstructure Matrix precipitates

Roll Vortices in the Boundary Layer Caused by a Concave Wind Profile: A Theoretical Study

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Atmospheric and Oceanic Science Letters 2010年第6期3卷 308-311页

作者： liu hui-Zhi SANG Jian-Guo State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry （LAPC） Institute of Atmospherie Physics Chinese Academy of Sciences Beijing 100029 China Physies School Peking University Beijing 100871 China

The present study solves a two-layer atmospheric wave equation model with a lower atmosphere concave wind profile and cold-air outbreak over sea, while simultaneously proving that such a wind shear may cause neutral boundary layer roll vortices in the presence of disturbing sources upstream. Without thermal effects, the wind shear-induced waves have band structures at the top of the boundary layer that are similar to cloud street patterns observed over sea. This study proves that dynamic and thermal effects can act independently to initiate the roll vortices in the lower atmosphere. At the same time, a quantitative comparison shows that dynamic effects play a large role in the formation of roll vortices in the initial stage of cold-air outbreak and will be surpassed by thermal effects soon after surface heating commences.

关键词： roll vortex concave wind profile Ekman laver wind shear cold advection

Hot Corrosion Behavior of SiO_2–Al_2O_3–Glass Composite Coating on Ti–47Al–2Cr–2Nb Alloy: Diffusion Barrier for S and Cl

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Acta Metallurgica Sinica(English Letters) 2019年第5期32卷 599-606页

作者： Wen-Bo Li Lan-Lan liu Ying-Fei Yang Sheng-Long Zhu Fu-hui Wang Hunan Electric Power Co. Ltd. Institute of Advanced Wear and Corrosion Resistant and Functional Material Jinan University Laboratory of Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences

Type Ⅰ hot corrosion behavior of SiO_2-Al_2O_3-glass composite coating based on Ti-47 Al-2 Cr-2 Nb substrate was investigated in the mixture salt of 25 wt%NaCl + 75 wt%Na_2SO_4 at 850 °C. The results showed that there was a bidirectional ion exchange between composite coating and the film of mixed salts, and the sodium ion in the molten salts penetrated into the glass matrix of composite coating, while the potassium ion in the glass matrix dissolved into the molten salts. A decrease in hot corrosion rate was achieved for the coated alloy in comparison with the bared substrate due to the composite coating acting as a diffusion barrier to sulfur and chlorine and preventing the molten salts from diffusing to the coating/alloy interface during the hot corrosion exposure. Additionally, the composite coating decreased the oxygen partial pressure at the coating/alloy interface and promoted the selective oxidation of Al to form a protective Al_2O_3 layer.

关键词： Corrosion Composite coating Ti–47Al–2Cr–2Nb alloy Diffusion

Dried Rehmannia root protects against glutamate-induced cytotoxity to PC12 cells through energy metabolism-related pathways

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Neural Regeneration Research 2017年第8期12卷 1338-1346页

作者： Yong liu Lei liu Xi-xiang Ying Wen-juan Wei Chao Han Yang liu Chun-hui Han Ai-jing Leng Jing-yun Ma Jing liu Regenerative Medicine Center the First Affiliated Hospital of Dalian Medical University Dalian Liaoning Province China Department of Traditional Chinese Medicine the First Affiliated Hospital of Dalian Medical University Dalian Liaoning Province China Liaoning University of Traditional Chinese Medicine Shenyang Liaoning Province China Traditional Chinese Medicine Pharmacy the First Affiliated Hospital of Dalian Medical University Dalian Liaoning Province China

Rehmannia has been shown to be clinically effective in treating neurodegenerative diseases; however, the neuroprotective mechanisms remain unclear. In this study, we established a model of neurodegenerative disease using PC12 cytotoxic injury induced by glutamate. The cells were treated with 20 mM glutamate in the absence or presence of water extracts of dried Rehmannia root of varying concentrations（70%, 50% and 30%）. The different concentrations of Rehmannia water extract significantly increased the activity of glutamate-injured cells, reduced the release of lactate dehydrogenase, inhibited apoptosis, increased the concentrations of NADH, NAD and ATP in cells, ameliorated mitochondrial membrane potential, and reduced the levels of light chain 3. Taken together, our findings demonstrate that Rehmannia water extracts exert a cytoprotective effect against glutamate-induced PC12 cell injury via energy metabolism-related pathways.

关键词： nerve regeneration Rehmannia water extracts glutamate PC12 cells autophagy energy metabolism neural regeneration

Enhancing anti-oxidation and thermal-radiation performance of the repaired borosilicate glass coating on C/C composites by Sm-doping

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Journal of Materiomics 2022年第2期8卷 417-426页

作者： Han-hui Wang liu Teng Jing-An Kong Xue-Song liu Xiao-Hong Shi He-Jun Li State Key Laboratory of Solidification Processing Carbon/Carbon Composites Research CenterNorthwestern Polytechnical UniversityXi'anShaanxi710072China

To repair the damaged SiC coated C/C composites,a double-layer system including a Sm-doped boro-silicate glass external layer and a SieSiC inner layer was prepared by a slurry-based laser cladding *** oxidation experiment and indirect/direct thermal-radiation measurements were *** results showed that the absorbance of borosilicate glass to the laser at 900e1200 nm was improved significantly by ***,the repaired coating with a more compact structure and better oxidation resistance was *** oxidation at 1773 K for 10 h,the mass loss of the damaged sample could be reduced by 74.98%with *** increasing laser-absorption and reducing viscosity,the thermal-radiation property of the repaired coating was enhanced to decrease the surface temperature greatly.A repair system with excellent thermal protection performance was achieved.

关键词： Coating repair Laser cladding Rare earth Oxidation resistance Thermal radiation

Synthesis and Characteristics of Electrodeposited CoxZn1-x Nanorods

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Chinese Physics Letters 2010年第6期27卷 203-205页

作者： liu Li-Hu GU Jian-Jun LI Hai-Tao CAI Ning SUN hui-Yuan College of Physics Science and Information Engineering Hebei Normal University Shijiazhuang 050016 Key Laboratory of Advanced Films of Hebei Province Shijiazhuang 050016 Department of Physics Hebei Chengde Teachers College Chengde 067000

CoxZn1-x nanorod arrays were fabricated by electrodeposition in porous anodic aluminum oxide templates at different electric potentials. X-ray diffraction and transmission electron microscopy indicate that highly-ordered and uniform nanorods have been fabricated. The amounts of Co and Zn contents are investigated using energy dispersive spectroscopy, which demonstrates that the atom ratio of the alloy nanorods changes with the deposition potential. In addition, magnetic measurements show that the magnetic isotropy Co-rich CoZn nanorods will change to magnetic anisotropy nanorods with the easy axis parallel to the rod long axis with decreasing Co content.

关键词： Processing Dispersants Measurement Microscopy Cobalt

Effect of sevoflurane on tissue permeability of lung ischemia-reperfusion injury in rats

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Asian Pacific Journal of Tropical Medicine 2014年第4期7卷 276-279页

作者： Xiao-hui Li Zhong-Hua liu Hong-Bing Ma Yong Li hui Zhao Jian-Bo Che Wei-Chao liu Gong-Ning Shi Huaihe River Hospital Henan University Medical School Henan University

Objective:To investigate the effect of sevoflurane on tissue permeability of lung ischemiareperfusion injury(LIRI)in ***:A total of 45 wistar rats were randomly divided into3 groupsⅠ,Ⅱ,Ⅲ.Modified Eppinger method was adopted to establish the rat lung ischemiareperfusion injury ***Ⅰserved as the control group,groupⅡas ischemia reperfusion group,groupⅢas sevoflurane ischemia-reperfusion *** gas index,lung permeability index(LPI)change,lung tissue pathology change and lung water content were observed and compared between groups of rats at different time ***:During ischemia reperfusion,all rats kept balance of the MAP during different time points,SPO_2 of groupⅡandⅢdecreased significantly thanⅠgroup(P<0.05);after reperfusion lung permeability index in GroupⅡandⅢwas higher than the control group significantly(P<0.05),120 min after reperfusion LPI change and iujury of groupⅢwas significantly lower thanⅡgroup(P<0.05);interstitial and alveolar cavity effusion in of groupⅢwere lower than that of groupⅡ.Conclusions:Sevoflurane pretreatment can reduce the lung tissue permeability,and LIRI plays a protective role in LIRI.

关键词： Sevoflurane Rats Lung ischemia-reperfusion Protection