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Effect of H impurity on misfit dislocation in Ni-based single-crystal superalloy:molecular dynamic simulations

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Chinese Physics B 2012年第2期21卷 407-412页

作者： yu Tao Xie Hong-Xian Wang Chong-yu Central Iron and Steel Research Institute Beijing 100081China Department of Physics Tsinghua UniversityBeijing 100084China School of Mechanical Engineering Hebei University of TechnologyTianjin 300132China

The effect of H impurity on the misfit dislocation in Ni-based single-crystal superalloy is investigated using the molecular dynamic simulation. It includes the site preferences of H impurity in single crystals Ni and Ni3Al, the interaction between H impurity and the misfit dislocation and the effect of H impurity on the moving misfit dislocation. The calculated energies and simulation results show that the misfit dislocation attracts H impurity which is located at the γ/γ′ interface and Ni3Al and H impurity on the glide plane can obstruct the glide of misfit dislocation, which is beneficial to improving the mechanical properties of Ni based superalloys.

关键词： molecular dynamic H impurity misfit dislocation Ni-based superalloy

Associations between Lesion Locations and Stroke Recurrence in Survivors of First-ever Ischemic Stroke:A Prospective Cohort Study

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Current Medical Science 2020年第4期40卷 708-718页

作者： Pe-jing YANI Li-sha HOU Mi-er LI Zhen-xing LU Feng-yu ZHAN Meng-dong RAN Ji-je LI Lu ZHANG Rong YANG Mu-ke ZHOU Cai-rong ZHU Department of Epidemiology and Health Statistics West China School of Public Health and West China Fourh HospitalSichuan UniversityChengdu 610044China National Clinical Research Center for Geriatrics West China HospitalSichuan UniversityChengdu 610044China The First Clinical College of Lanzhou University Lanzhou 730000China Department of Medical Record West China Second University SchoolChengdu 610044China Department of Neurology West China Hospital of Sichuan UniversitChengdu 610044China

Summary:Several studies have indicated that stroke survivors with multiple lesions or with larger lesion volumes have a higher risk of stroke ***,the relationship between lesion locations and stroke recurrence is *** conducted a prospective cohort study of first-ever ischemic stroke survivors who were consecutively enrolled from January 2010 to December *** recurrence was assessed every 3 months after post-discharge via telephone interviews by trained *** locations were obtained from hospital-based MRI or CT scans and classified using two classification systems that were based on cerebral hemisphere or vascular territory and brain anatomical *** parametric survival models using the proportional hazards scale(PH model)were used to analyze the time-to-event *** 633 survivors,63.51%(n-402)had anterior circulation ischemia(ACI),and morc than half of all ACIs occurred in the *** a median follow-up of 2.5 years,117(18.48%)survivors developed a recurrent *** results of the multivariate PH model showed that survivors with non-brain lesions were at higher risk of recurrence than those with right-side lesions(HR,2.79;95%CI,1.53,5.08;P-0.001).There was no increase in risk among survivors with left-side lesions(HR,0.97;95%CI,0.53,1.75;P=0.914)or both-side lesions(HR,1.24;95%CI,0.75,2.07;P-0.401)compared to those with right-side ***,there were no associations between stroke ecurrence and lesion locations that were classified based on vascular territory and brain anatomical *** was concluded that first-ever ischemic stroke survivors with non-brain lesion had higher recurrence risk than those with right-side lesion,although no significant associations were found when the lesion locations were classified by vascular territory and brain anatomical structures.

关键词： ischemic stroke lesion location prevention recurrence flexible parametric survival models survival analysis

Existence of Nontrivial Solutions for Superlinear Three-Point Boundary Value Problems

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Acta Mathematicae Applicatae Sinica 2017年第4期33卷 1043-1052页

作者： Hong-yu LI College of Mathematics and Systems Science Shandong University of Science and Technology Qingdao 266590China Mathematics and Science College Shanghai Normal University Shanghai 200234 China

In this paper, we investigate the existence of nontrivial solutions for some superlinear second order three-point boundary value problems by applying new fixed point theorems in ordered Banach spaces with the lattice ... 详细信息

关键词： lattice three-point boundary value problem sign-changing solution

A comparative study on the medium-long term results of endovascular repair and open surgical repair in the management of ruptured abdominal aortic aneurysms

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Chinese Medical Journal 2013年第24期126卷 4771-4779页

作者： HAN Yan-shuo ZHANG Jian XIA Qian LIU Zhi-min ZHANG Xiao-yu WU Xiao-yu LUN yu XIN Shi-jie DUAN Zhi-quan XU ke Department of Vascular and Thyroid Surgery Department of Vascular Intervention Department of Vascular and Thyroid Surgery the First Hospital ofChina Medical University Shenyang Liaoning 110001 China

Background Although it is generally acknowledged that patients with ruptured abdominal aortic aneurysm （rAAA） obtain the greatest benefit from endovascular repair （EVAR）, convincing evidence on the medium-long term effect is lacking. The aim of this study was to compare and summarize published results of rAAA that underwent EVAR with open surgical repair （OSR）. Methods A search of publicly published literature was performed. Based on an inclusion and exclusion criteria, a systematic meta-analysis was undertaken to compare patient characteristics, complications, short term mortality and medium-long term outcomes. A random-effects model was used to pool the data and calculate pooled odds ratios and weighted mean differences. A quantitative method was used to analyze the differences between these two methods. Results A search of the published literature showed that fourteen English language papers comprising totally 1213 patients with rAAA （435 EVAR and 778 OSR） would be suitable for this study. Furthermore, 13 Chinese studies were included, including 267 patients with rAAA totally, among which 238 patients received operation. The endovascular method was associated with more respiratory diseases before treatment （OR=1.81, P=0.01）, while there are more patients with hemodynamic instability before treatment in OSR group （OR=1.53, P=0.031）. Mean blood transfusion was 1328 ml for EVAR and 2809 ml for OSR （weighted mean difference （WMD） 1500 ml, P=0.014）. The endovascular method was associated with a shorter stay in intensive care （WMD 2.34 days, P 〈0.001） and a shorter total post- operative stay （WMD 6.27 days, P 〈0.001）. The pooled post-operative complication rate of respiratory system and visceral ischemia seldom occurred in the EVAR group （OR=0.48, P 〈0.001 and OR=0.28, P=0.043, respectively）. The pooled 30-day mortality was 25.7% for EVAR and 39.6% for OSR, and the odds ratio was 0.53 （95% confidence interval （CI） 0.41-0.70, P 〈0.001）. There was not, however, any signi

关键词： aortic aneurysm abdominal, aortic rupture, endovascular procedures medium-long term effect,meta-analysis

Comparative Study of Bypass-Current MIG Welded–Brazed Aluminum/Galvanized Steel and Aluminum/Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2017年第8期30卷 721-730页

作者： yu-Gang Miao Guang-yu Chen Peng Zhang Duan-Feng Han National key Laboratory of Science and Technology on Underwater Vehicle Harbin Engineering UniversityHarbin 150001 China

A bypass-current metal inert-gas welding-brazing technology has been developed to join aluminum/galvanized steel and aluminum/stainless steel. Microstructure, intermetallic compounds and hardness distribution of the joints were studied by optical microscopy, scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction analysis and microhardness tests. Comparative study on both types of joints was carried out. During aluminum to galvanized steel assembling, finer seam was obtained under a more stable process. A uniform interfacial reaction layer with a thickness of 2-4 μm was formed. During aluminum to stainless steel assembling, an uneven interfacial reaction layer with a thickness of 5-45μm was formed. Intermetallic compounds at the interface of aluminum/galvanized steel were identified as Fe-Al- Si-Zn complex phases, while Fe-Al-Cr-Ni complex phases were found at the aluminum/stainless steel interface. Microhardness of interfacial layer increases rapidly within reaction layer due to possible brittle intermetallic compounds.

关键词： Aluminum alloy Steel Intermetailic compounds Dissimilar joining

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基于创新能力培养的线上线下融合教学模式

教育教学论坛 2025年第1期 117-120页

作者：陈伟马丽娜卞玉洁陈羽国防科技大学气象海洋学院湖南长沙410073

培养学生的创新能力是高等教育一贯的主题。针对理论性课程对学生创新能力培养不足的问题,提出PP-BOPPPSPP教学模型,并基于该模型打造线上线下融合教学模式,精准使用丰富的教学资源,精心设计完整的教学环节,精确把握不同的师生任务,从... 详细信息

培养学生的创新能力是高等教育一贯的主题。针对理论性课程对学生创新能力培养不足的问题,提出PP-BOPPPSPP教学模型,并基于该模型打造线上线下融合教学模式,精准使用丰富的教学资源,精心设计完整的教学环节,精确把握不同的师生任务,从而有效促进学生创新能力的提升。以“海洋技术导论”课程某一课次为例,实践了线上线下融合教学模式,并取得了显著成效,对基于高等院校理论课程培养创新型人才具有重要的指导意义。

关键词：创新能力培养线上线下融合教学模式教学模型

Water droplet impact on superhydrophobic surfaces with microstructures and hierarchical roughness

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Science China(Physics,Mechanics & Astronomy) 2014年第7期57卷 1376-1381页

作者： HAO PengFei LV CunJing NIU FengLei yu yu Department of Engineering Mechanics Tsinghua University State key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University

Quantitative correlation between the critical impact velocity of droplet and geometry of superhydrophobic surfaces with microstructures is systematically *** data shows that the critical impact velocity induced wetting transition of droplet on the superhydrophobic surfaces is strongly determined by the perimeter of single micropillar,the space between the repeat pillars and the advancing contact angle of the sidewall of the *** proposed model agrees well with the experimental results,and clarifies that the underlying mechanism which is responsible for the superhydrophobic surface with hierarchical roughness could sustain a higher liquid pressure than the surfaces with microstructures.

关键词： impact velocity superhydrophobic advancing contact angle

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防空火箭炮射序优化分析

南京理工大学学报 2012年第1期36卷 132-136页

作者：王雷马大为于存贵周克栋南京理工大学机械工程学院江苏南京210094

为了提高防空火箭炮射击密集度,该文对防空火箭炮采用群组发射方式的多种可能射序进行了研究。在建立防空火箭炮动力学模型的基础上,考虑群组发射方式采用多枚弹同时点火的特点,根据射序编制的基本原则和同时发射两弹之间要保持较远安... 详细信息

为了提高防空火箭炮射击密集度,该文对防空火箭炮采用群组发射方式的多种可能射序进行了研究。在建立防空火箭炮动力学模型的基础上,考虑群组发射方式采用多枚弹同时点火的特点,根据射序编制的基本原则和同时发射两弹之间要保持较远安全距离的要求拟定多种射序方案。以起始扰动为优化目标,对各射序方案进行动力学仿真和数据处理,优选出了较优的射序。结果表明,火箭弹群组的合理组合和同组弹中心对称射序方案能够有效提高射击密集度,为防空火箭炮的射序制定提供了依据。

关键词：防空火箭炮射序起始扰动优化

Effect of nano-SiC particles on the corrosion resistance of NiP-SiC composite coatings

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International Journal of Minerals,Metallurgy and Materials 2009年第4期16卷 444-451页

作者： Xue-tao yuan Dong-bai Sun Hong-ying yu yu Wang School of Materials Science and Technology University of Science and Technology Beijing Beijing 100083 China Beijing Engineering-Research Center for Surface Nano-Technology Beijing 100083 China

NiP-SiC （≈1 1wt% P） composite coatings were electroplated in a Brenner type plating bath. The coatings had amorphous nano-phase composite structure. Direct current and alternating current electrochemical tests were carried out on such coatings in a 3.5wt% solution of NaCl to evaluate their corrosion resistance. The potentiodynamic polarization, electrochemical impedance spectroscopy （EIS） tests, and exposure experiments all show that the corrosion resistance of NiP-SiC coatings first increases and then decreases when the SiC content increases, but the corrosion resistance of NiP-SiC composite coating is better than that of amorphous NiP coatings.

关键词： electroplating composite coating nanoparticle corrosion resistance electrochemical impedance spectroscopy