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Nanocrystal Model for Liquid Metals and Amorphous Metals

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Journal of Materials Science & Technology 2010年第1期26卷 69-74页

作者： x.L. Tian, C.W. Zhan, J.x. Hou, x.C. Chen and J.J. sun Key Laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, Jinan 250061, China [a] Key Laboratory of Liquid Structure and Heredity of Materials Ministry of Education Shandong University Jinan 250061 China

A nanocrystal model for liquid metals and amorphous metals has been developed. With the nanocrystal model, the broadening peak profiles （BPPs） of Cu, Al, Al65Cu20Fe15 alloy, Cu7oNi30 alloy and Fe50Si50 alloy were gained by broadening the x-ray diffraction （xRD） peaks of a crystal lattice. By comparing the BPPs with the xRD intensity curves measured on the liquid metals, it is found that the BPPs are closely in agreement with the xRD intensity curves, respectively, except the FesoSiso alloy. Therefore, the nanocrystal model can be used to determine if the atomic cluster structure of the liquid metal is similar to the structure of its crystal lattice.

关键词： Liquid metal Atomic cluster Structure Crystal lattice

Sample selection for models to represent ceramic cores fabricated by stereolithography three-dimensional printing

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Journal of Materials Science & Technology 2022年第26期121卷 117-123页

作者： x.L.An J.J.Liang J.G.Li J.W.Chen Y.Z.Zhou x.F.sun School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Space Manufacturing Technology(CAS Key Lab) Beijing 100094China

Ceramic cores with good chemical stability and moderate mechanical properties near casting temperatures of 1550℃ for example are used for the manufacturing of internal structures of hollow blades,requiring complex structures and high precision[1–3].However,traditional preparation method based on investment casting is tedious,requiring not only long production cycles but also high cost[4].

关键词： investment printing ceramic

Evaluation of dynamic development of grain structure during friction stir welding of pure copper using a quasi in situ method

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Journal of Materials Science & Technology 2019年第7期35卷 1412-1421页

作者： x.C.Liu Y.F.sun T.Nagira K.Ushioda H.Fujii Joining and Welding Research Institute Osaka University11-1 MihogaokaIbarakiOsaka567-0047Japan School of Materials Science and Engineering Northwestern Polytechnical UniversityXi'an710072China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou450001China

By employing a quasi in situ method, we investigated the dynamic evolution of the grain structure con-sidering the material flow, strain, and strain rate in the friction stir welding of pure copper. The tool' stop action' and rapid cooling were employed and a brass foil was used as a marker to show the material flow path. The grain structure along the material flow path was characterised using electron backscatter diffraction. Static recrystallization occurs for the work-hardened base material in the preheating stage in front of the tool In the acceleration flow stage, grains are significantly refined by plastic deforma-tion, discontinuous dynamic recrystallization, annealing twinning during the strain-induced boundary migration and slight continuous dynamic recrystallization. In the deceleration flow stage, due to a strain reversal, the grain first coarsens, and is thereafter refined again. Finally, the hot-deformed material in the shoulder-affected zone is ‘frozen’ directly whereas that in the probe-affected zone undergoes signif-icant annealing;thus, the recrystallized microstructure and 45°-rotated cube texture are obtained in the probe-affected zone.

关键词： Friction stir welding Grain structure Material flow Pure copper EBSD

A model predictive based UUV control design from kinematic to dynamic tracking control 36

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A model predictive based UUV control design from kinematic t...

Effect of post-bond heat treatment on the microstructure and high temperature mechanical property of a TLP bonded γ'-strengthened co-based single crystal superalloy

第36届中国控制会议

作者： Bing sun Wenyang Gan Daqi Zhu Wei Zhang Simon x Yang Lab.of Underwater Vehicles and Intelligent Systems Shanghai Maritime University Advanced Robotics and Intelligent Systems Laboratory University of Guelph

ISBN: (纸本)9781538629185

In this paper,the trajectory tracking control problem with model predictive control approach is investigated for Unmanned Underwater Vehicle（UUV） ***,the kinematic tracking controller based on model predictive control（MPC） is applied to reach the tracking control in a kinematic *** with conventional backstepping control,MPC can solve the speed jump control problem very ***,to deal with dynamic tracking control with the nonlinear UUV dynamic model,the computation cost of MPC will be tremendous and cannot meet the real-time ***,in order to deal with this problem,the MPC algorithm is cooperated with sliding mode control to reach a dynamic tracking control which can be robust with modeling uncertainty and ***,the experimental results show that the proposed method can solve speed jump and robust enough for tracking control compared with other benchmark method.

关键词： Unmanned Underwater Vehicle trajectory tracking model predictive control sliding mode control speed jump

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Journal of Materials Science & Technology 2021年第21期80卷 244-258页

作者： S.Y.Wang Y.sun C.Y.Cui x.F.sun Y.Z Zhou Y.M.Ma H.L.An Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Harbin Welding Institute China Academy of Machinery Science and TechnologyHarbin 150028China

Post-bond heat treatment(PBHT) applied to a transient liquid phase(TLP) bonding joint is an effective approach to remove the brittle borides and improve its ***,we proposed two types of PBHT strategies to obtain a TLP bonded γ'-strengthened Co-based single crystal superalloy,and the microstructural characteristics and tensile properties of the two heat treated joints were compared to identify the optimal PBHT *** evolution of the brittle boride in the joint after the PBHT was studied by using in-situ *** experimental results allowed to provide a theoretic model to quantitatively evaluate the distribution of the brittle phase after the optimal PBHT and analyze the joint fractures to understand the failure *** obtained results revealed that a post-bond solid solution treatment performed to the joint at a high temperature(over 1275℃) could decrease the area fraction of the boride from 7.2 % to 1.4 % and increase the elongation from 1.9 % to 7.8 %.This work emphasizes the relevance of solid solution temperature when a PBHT strategy is applied.

关键词： Transient liquid phase(TLP) γ'-strengthened co-based single crystal superalloy Heat treatment sequence Brittle boride Tensile property

A survey of weak stability boundaries in the sun-Mars system

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Research in Astronomy and Astrophysics 2015年第3期15卷 376-392页

作者： Jian Li Yi-Sui sun School of Astronomy and Space Science & Key Laboratory of Modern Astronomy and Astrophysics in Ministry of Education Nanjing University

We investigate the weak stability boundary （WSB） for a new primary, Mars, in the framework of the planar circular restricted 3-body problem, and also in the pla- nar bicircular restricted 4-body problem by including a perturbation due to Jupiter. For the sake of a simple stability/instability criterion, our computations have been done us- ing the equations of motion in polar coordinates. It is found that the relative size of the weakly stable sets around Mars is much larger than that of the Earth-Moon and the sun-Jupiter systems, as the mass ratio of the sun-Mars system is significantly smaller. We propose that this difference could be scaled by the Hill radius. In an enlarged view of the domain close to Mars, the geometry of the WSB has been presented for various parameters and compared to previous works. Our results also show that Jupiter＇s grav- itational force would strongly affect the Martian stable regions and should be taken into account to design a ballistic capture trajectory.

关键词： celestial mechanics

Trends of alkaline phosphatase to prealbumin ratio in patients with hepatitis B linked to hepatocellular carcinoma development

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World Journal of Gastroenterology 2025年第2期31卷 42-51页

作者： Wen-Chong Zhen Jing sun xue-Ting Bai Qian Zhang Zi-Han Li Yi-xin Zhang Rong-xuan xu Wei Wu Zhi-Han Yao Chun-Wen Pu xiao-Feng Li School of Public Health Dalian Medical UniversityDalian 116044Liaoning ProvinceChina Graduate School Dalian Medical UniversityDalian 116044Liaoning ProvinceChina Dalian Public Health Clinical Center Dalian Municipal Research Institute for Public HealthDalian 116001Liaoning ProvinceChina Department of Epidemiology and Health Statistics Dalian Medical UniversityDalian 116044Liaoning ProvinceChina

BACKGROUND Chronic hepatitis B often progresses silently toward hepatocellular carcinoma(HCC),a leading cause of mortality *** detection of HCC is crucial,yet *** To investigate the role of dynamic changes in alkaline phosphatase to prealbumin ratio(APR)in hepatitis B progression to *** Data from 4843 patients with hepatitis B(January 2015 to January 2024)were *** incidence rates in males and females were compared using the log-rank *** were evaluated using Kaplan–Meier *** Linear Mixed-Effects Model was applied to track the fluctuation of APR levels over ***,Joint Modeling of Longitudinal and Survival data was employed to investigate the temporal relationship between APR and HCC *** The incidence of HCC was higher in *** ensure the model’s normality assumption,this study applied a logarithmic transformation to APR,yielding *** levels were higher in females(t=5.26,P<0.01).A 1-unit increase in ratio correlated with a 2.005-fold higher risk of HCC in males(95%CI:1.653-2.431)and a 2.273-fold higher risk in females(95%CI:1.620-3.190).CONCLUSION Males are more prone to HCC,while females have higher APR *** no baseline APR link,rising APR indicates a higher HCC risk.

关键词： Alkaline phosphatase to prealbumin ratio Chronic hepatitis B patients Hepatocellular carcinoma Retrospective cohort study Linear Mixed-Effect Mode Joint Modelling of Longitudinal and Survival data

Full privacy preserving electronic voting scheme

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The Journal of China Universities of Posts and Telecommunications 2012年第4期19卷 86-93页

作者： PANG Lei sun Mao-hua LUO Shou-shan WANG Bai x1N Yang School of Computer Science Beijing University of Posts and Telecommunications Beijing 100876 China National Engineering Laboratory for Disaster Backup and Recovery Beijing 100876 China Beijing Safe-Code Technology Company Limited Beijing 100082 China

Privacy is an important issue in electronic voting. The concept of ＇full privacy＇ in electronic voting was firstly proposed, not only the privacy of voters is concerned, but also the candidates＇. Privacy preserving electronic election architecture without any trusted third party is presented and a general technique for k-out-of-m election based on distributed E1Gamal encryption and mix-match is also provided. The voters can compute the result by themselves without disclosing their will and the vote of the losing candidates. Moreover, whether the vote of winner candidate is more than a half can be verified directly. This scheme satisfies ＇vote and go＇ pattern and achieves full privacy. The correctness and security are also analyzed.

关键词： electronic voting full privacy secure multi-party computation cryptography

Oxygen and Nitrogen Effects on MC Carbide in K465 Nickel-Base Superalloy

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稀有金属材料与工程 2009年第A03期38卷 13-16页

作者： Wang L N Zheng Q sun x F Guan H R Hu Z Q Institute of Metals Research Chinese Academy of Sciences Shenyang 110015 China

Effects of oxygen and nitrogen on MC carbide in nickel-base superalloy K465 were investigated, because neither of the two gas elements was found to decide MC carbide morphology monotonically. The morphology of MC carbide under alloy solidified in conventional investment casting condition was observed to transform from script-type to block-type with the total oxygen and nitrogen content (gas content) in samples rising up from 1.2×10-6 mol/g to 2.6×10-6 mol/g. The area fraction and composition of the MC carbide also varied with increase of gas content. However, the morphology of MC carbide kept to be script-type even when gas content was up to 3.4×10-6 mol/g in samples solidified with a much higher cooling rate. These results indicate that effects of gas content on formation of MC carbide can be observed in specimens solidified with low cooling rate, but such changes in MC carbide cannot be found when the cooling rate is high.

关键词：氧碳化物氮含量物理性能碳化物