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| 1 | Improving the Corrosion Resistance of ZEK100 Magnesium Alloy by Combining High-Pressure Torsion Technology with Hydroxyapatite Coating显示文摘Recently,magnesium and its alloys have attracted more and more attention as promising implant materials due to their excellent properties such as good biocompatibility,biodegradation,non-toxicity and comparable mechanical properties with natural bone.They can be gradually degraded and absorbed so as to avoid the second surgery for implants removal after the tissues are healed completely.In addition,they are also able to prevent the stress shielding effect in human body environment because of the density,elastic modulus and yield strength of magnesium closer to the bone.Unfortunately,the high corrosion rate which causes early mechanical failure of the implants in physiological environment limits the widespread use of magnesium alloys for clinical application in biology.And the high corrosion process usually causes huge hydrogen evolution and alkalinization,resulting in problems against the implants as well as the surrounding tissues.In order to enhance the corrosion resistance of magnesium alloys,in this study,the ZEK100 magnesium alloy was pre-deformed with a highpressure torsion(HPT)process and then fabricated hydroxyapatite(HA)coatings with different contents of Mg(OH)2 nanopowder via hydrothermal method.The specimens were characterized by scanning electron microscope(SEM)and X-ray diffraction(XRD).At the same time,prior and after the HPT procedure,the metallography,microhardness and tensile tests of specimens were characterized.Meanwhile,the corrosion behavior of the specimens was evaluated by electrochemical impedance spectroscopy(EIS)and hydrogen evolution tests.And the interface bonding strength of the HA coating on the magnesium alloy substrate was evaluated by a tape adhesion test/scratch test.Results showed that HPT processing refined the grain size and introduced a great number of twins,resulting in the enhancement of microhardness and Young’s modulus of ZEK100 magnesium alloy,but hardness values at the edge were higher than those at the center due to the uneven shear strain.At the same conditions,the HA coating on HPT-ZEK was denser,thicker than that on ZEK sample and the crystal sizes of HA were smaller on HPT-ZEK.These were attributed to fine,uniform distributed secondary phases and lots of fine grains,twins,grain boundaries in HPT-ZEK substrates which can provide more nucleation sites for the HA crystal.In terms of the amount of Mg(OH)2 nanopowder,Mg(OH)2 nanopowder significantly influenced the microstructure and thickness of the HA coating.And at a 0.3 mg/mL content of Mg(OH)2 nanopowder,there was the densest,thickest HA coating on magnesium alloys,and the crystal size of HA was minimum.Specifically,the HA coating thickness on ZEK-03(0.3 mg/mL Mg(OH)2 nanopowder)was 1.8 times of that on ZEK-00(0 mg/mL Mg(OH)2 nanopowder),while the HA coating thickness on HPT-03 was 2.6 times of that on ZEK-00.And the adhesion strength of HA coating on HPT-03 substrate was better than that on ZEK-03.In addition,HPT technology and surface modification by HA coating simultaneously increased the corrosion resistance of ZEK100 magnesium alloy and the corrosion of HPT-ZEK samples occurred in a more uniform manner,while it was pitting on the surface of ZEK100 magnesium alloy.Therefore,there was the best corrosion resistance on HPT-03 sample,which could promote the application of magnesium alloys in biomedical fields. | Qite Li Wenbo Ye Hong Gao Lilan Gao | 2019 | 医用生物力学2019，34，A01： | 5 |
| 2 | Influence of Twinning Texture on the Corrosion Fatigue Behavior of Extruded Magnesium Alloys显示文摘Bio-magnesium alloys have received great attention due to their degradability and biocompatibility.Corrosion fatigue failure is a huge challenge in vivo for bio-magnesium alloy implants.Understanding the eff ects of twinning textures on the corrosion fatigue of magnesium alloys is meaningful for the applications.In the current study,pre-compression strains of 2%and 4%were carried out on extruded rods.The effects of twinning texture on the corrosion performance and corrosion fatigue resistance were investigated.The hydrogen evolution tests indicated that twinning texture enhanced the corrosion resistance of longitudinal cross section by improving uniformity of surface energy.The results of corrosion fatigue tests indicated that the differences in mechanical damage caused by twinning texture dominated the corrosion fatigue behavior under high stress amplitude.The secondary cracks of surface deteriorated the corrosion fatigue resistance of the original specimens under low stress amplitude.The compact corrosion film and the re-passivation of matrix suppressed the hydrogen induced cracking,thereby improving the corrosion fatigue resistance of the pre-compression specimens. | Jiaqi Hu Qite Li Hong Gao | 2021 | Acta Metallurgica Sinica(English Letters)2021，34，1： | 0 |
| 3 | Transcriptome-wide profiling of RNA N^(4)-cytidine acetylation in Arabidopsis thaliana and Oryza sativa显示文摘Acetylation of N^(4)-cytidine(ac^(4)C)has recently been discovered as a novel modification of mRNA.RNA ac^(4)C modification has been shown to be a key regulator of RNA stability,RNA translation,and the thermal stress response.However,its existence in eukaryotic mRNAs is still controversial.In plants,the existence,distribution pattern,and potential function of RNA ac^(4)C modification are largely unknown.Here we report the presence of ac^(4)C in the mRNAs of both Arabidopsis thaliana and rice(Oryza sativa).By comparing two ac^(4)C sequencing methods,we found that RNA immunoprecipitation and sequencing(acRIP-seq),but not ac^(4)C sequencing,was suitable for plant RNA ac^(4)C sequencing.We present transcriptome-wide atlases of RNA ac^(4)C modification in A.thaliana and rice mRNAs obtained by acRIP-seq.Analysis of the distribution of RNA ac^(4)C modifications showed that ac^(4)C is enriched near translation start sites in rice mRNAs and near translation start sites and translation end sites in Arabidopsis mRNAs.The RNA ac^(4)C modification level is positively correlated with RNA half-life and the number of splicing variants.Similar to that in mammals,the translation efficiency of ac^(4)C target genes is significantly higher than that of other genes.Our in vitro translation results confirmed that RNA ac^(4)C modification enhances translation efficiency.We also found that RNA ac^(4)C modification is negatively correlated with RNA structure.These results suggest that ac^(4)C is a conserved mRNA modification in plants that contributes to RNA stability,splicing,translation,and secondary structure formation. | Bin Li Donghao Li Linjun Cai Qiting Zhou Cong Liu Jianzhong Lin Yixing Li Xiaoying Zhao Li Li Xuanming Liu Chongsheng He | 2023 | Molecular Plant2023，16，6： | 0 |
| 4 | Image editing by object-aware optimal boundary searching and mixed-domain composition显示文摘When combining very different images which often contain complex objects and backgrounds,producing consistent compositions is a challenging problem requiring seamless image editing. In this paper, we propose a general approach, called objectaware image editing, to obtain consistency in structure,color, and texture in a unified way. Our approach improves upon previous gradient-domain composition in three ways. Firstly, we introduce an iterative optimization algorithm to minimize mismatches on the boundaries when the target region contains multiple objects of interest. Secondly, we propose a mixeddomain consistency metric for measuring gradients and colors, and formulate composition as a unified minimization problem that can be solved with a sparse linear system. In particular, we encode texture consistency using a patch-based approach without searching and matching. Thirdly, we adopt an objectaware approach to separately manipulate the guidance gradient fields for objects of interest and backgrounds of interest, which facilitates a variety of seamless image editing applications. Our unified method outperforms previous state-of-the-art methods in preserving global texture consistency in addition to local structure continuity. | Shiming Ge Xin Jin Qiting Ye Zhao Luo Qiang Li | 2018 | Computational Visual Media2018，4，1： | 0 |
| 5 | High-lying excited states in ^10Be from the ^9Be(^9Be,^10Be)^8Be reaction显示文摘A transfer-reaction experiment of ~9Be(~9Be,^(10)Be)~8Be was performed at a beam energy of 45 Me V.Excited states in ^(10)Be up to 18.80 Me V are produced using missing mass and invariant mass methods.Most of the observed high-lying resonant states,reconstructed from theα+~6He and t+~7Li decay channels,agree with the previously reported results.In addition,two new resonances at 15.6 and 18.8 Me V are identified from the present measurement.The 18.55 Me V state is found to decay into both the t + ~7Lig:s: and t + ~7Li?(0.478 MeV) channels, with a relative branching ratio of 0:93 ± 0:33. Further theoretical investigations are encouraged to interpret this new information on cluster structure in neutron-rich light nuclei. | Wei Jiang YanLin Ye ZhiHuan Li ChengJian Lin QiTe Li YuCheng Ge JianLing Lou DongXing Jiang Jing Li ZhengYang Tian Jun Feng Biao Yang ZaiHong Yang Jie Chen HongLiang Zang Qiang Liu PengJie Li ZhiQiang Chen Yun Zhang Yang Liu XiaoHui Sun Jing Ma HuiMing Jia XinXing Xu Lei Yang NanRu Ma LiJie Sun | 2017 | Science China(Physics,Mechanics & Astronomy)2017，60，6： | 0 |
| 6 | 远离污垢的烹饪新体验——可旋转智能燃气灶显示文摘燃气灶在日常生活中是烹饪美味食物的必需品,但它们往往有难以清洁的角落和缝隙。这款UFO智能旋转炉采用高架燃烧器设计,只需一个开关就可以旋转90度。这种简单的机制使用户清理起来更加容易,也使得烹饪过程更加愉快。除了增加操作的乐趣外,通过旋转燃气灶还能腾出临时空间,最大限度地利用了厨房空间。通过触摸控制,还可以精确地调节火焰强度,以获得更好的烹饪效果。 | Li Zhaoping Wu Qiting Wu Shengjia Zhou Jinhui | 2023 | 工业设计2023，，11： | 0 |
| 7 | Enhanced monopole transition strength from the cluster decay of ^(13)C显示文摘The inelastic excitations and cluster decay of ^(13)C have been measured using the reaction,9Be(^(13)C, ^(13)C* →~9Be + α)~9Be. We observe strong excitation to the 14.3-MeV(1/2-) resonant state from the cluster-decay channel, leading to an enhanced monopole matrix element of(6.3 ± 0.6) fm^2. This large cluster-related monopole strength is a clear indication of the cluster-structure domination of this state and is consistent with the recent prediction of the orthogonality condition model(OCM). It would be interesting to further explore the three-center molecular rotational band that is initiated from the observed band-head. | Jun Feng YanLin Ye Biao Yang ChengJian Lin HuiMin Jia DanYang Pang ZhiHuan Li JianLing Lou QiTe Li XiaoFei Yang Jing Li HongLiang Zang Qiang Liu Wei Jiang ChenGuang Li Yang Liu ZhiQiang Chen HongYi Wu ChunGuang Wang Wei Liu Xiang Wang JingJing Li DiWen Luo Ying Jiang ShiWei Bai JinYan Xu NanRu Ma LiJie Sun DongXi Wang | 2019 | Science China(Physics,Mechanics & Astronomy)2019，62，1： | 0 |
| 8 | Fusion Studies with Low-intensity Beams Using the Active Target Time Projection Chamber显示文摘Fusion reactions play a very important role for the creation of heavier elements in the quiescent and explosive burning phases in stars.Fusion processes also generate the energy in the Sun that created and maintain life in our earth[1]. | Zhang Ningtao Zhang Zhichao Zhang Jinlong Tang Xiaodong Lu Chengui Gao Bingshui Li Yutian Li Kuoang Pu Tianlei Ru Longhui Wang Xinyu Xu Xiaodong Cai Ziwei Li Qite Ji Binfei Xu Jinyan | 2019 | IMP & HIRFL Annual Report2019，，1： | 0 |
| 9 | Investigation of electrode and hydrogen induced crack in welded joint of dissimilar steel显示文摘The welded joint of dissimilar heat-resisting steels 20Crl2MoV(F12)and 12 Cr2MoWVTiB(102)generally works around 600°C.In this paperthree kinds of ferritic electrodes are used for testing.They are R817 high-strength electrode(CrllMoVNi),R347 low-strength electrode(Cr2MoVWB)and newly-developed R507MoNb medium-strength electrode.The study on theinfluence of those three different electrodes on carbon migration,HIC and hy-drogen diffusion shows that medium-strength electrodes can well control thecarbon migration,and that the tendency to HIC in the joint formed by R817 issmaller than that by R347 instead.Considering the effect of weld metal transfor-mation on the restraint stress and hydrogen concentration of a joint,the hydro-gen distribution in the heat-affected zone(HAZ)is calculated by using finite ele-ment method(FEM)with stress and strain changing,and so the effect of thetransformation behaviour on HIC is revealed.In addition,newly-developedR507MoNb electrodes,tested the elevated-temperature property,oxidation re-sistance and creep rupture strength,have fulfilled the technical standards con-cerned and passed the examination of on-the-spot operation. | Zhang Zhiming Lu Daohua Li Zhonglin Harbin Institute of Technology Feng Qiting Peng Chuanliou Heilongjiang Electric Power Electrode Manufacturer,Harbin Wang Ruilin Northeast Electric Power Test Institute,Shenyang | 1992 | China Welding1992，2，2： | 0 |
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