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Development and application of software packages in welding engineering

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Frontiers of Materials Science 2011年第2期5卷 160-167页

作者： yan-hong wei Xiao-hong ZHAN Zhi-Bo DONG School of Material Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China State Key Laboratory of Advanced Welding Technology Production Harbin Institute of Technology Harbin 150001 China

The weldabiUty of some material is analyzed with simple calculating program in this paper, and weldability testing data are shared through database system. The welding procedures are designed with help of expert systems, and the knowledge is shared among welding engineers. Not only the preparing progress of the welding documents is completed with database systems but also the complex decision on the necessity of the qualification test according to the present procedure qualification records （PQRs） and manufacture codes is made. Moreover, the artificial neural network （ANN） technique is proven to be one of the effective ways to predict mechanical properties of welded joints when there are enough tested data to train the models. Finally, the achievements in modeling microstructure of welded joints are introduced, especially in solid transformation and grain growth in both heat-affected zone （HAZ） and welded molten pool.

关键词： welding software package, finiteelementmethod (FEM), welding procedurequalification, mechanical properties of welded joints expert system, database system

Aging precipitation characteristics and tensile properties of Al-Zn-Mg-Cu alloys with different additional Zn contents

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Rare Metals 2021年第8期40卷 2160-2166页

作者： Kai Wen Bai-Qing Xiong Yong-An Zhang Xi-Wu Li Zhi-Hui Li Li-Zhen yan hong-wei yan hong-wei Liu State Key Laboratory of Nonferrous Metals and Processes GRIMAT Engineering Institute Co.LTD.Beijing101407China GRINM Group Co. LTD.Beijing100088China

The increase in zinc content in Al-Zn-Mg-Cu alloys provides an effective method to enhance the *** electron microscopy(TEM)and tensile test were employed to analyze the microstructure and tensile properties,respectively,of Al-9.3 Zn-2.0 Mg-1.8 Cu alloy(9.3 Zn alloy)and Al-9.8 Zn-2.0 Mg-1.8 Cu alloy(9.8 Zn alloy)with single-and double-stage aging *** results showed that the two alloys possessed a closed strength under single-stage peak-aging *** for double-stage aging treatment,9.8 Zn alloy had a higher strength values than 9.3 Zn alloy under the same aging *** the second step aging time prolonging,the strength gap was *** main precipitates for the two alloys with single-stage peak-aging state were GP zones andη’phase,while there were a majority ofη’phases andηphases for the two alloys under typical double-stage over-aging *** double-stage overaging state,the proportion of precipitate with large size for9.3 Zn alloy was larger than that for 9.8 Zn ***,a more obvious trend was revealed for the double-stage overaging *** gap of strength between the two alloys was explained by the difference of precipitation characteristics via interaction mechanism between precipitates and dislocations.

关键词： Zn content Al-Zn-Mg-Cu alloy Precipitation characteristics Tensile properties

Value of contrast-enhanced ultrasound combined with elastography in evaluating cervical lymph node metastasis in papillary thyroid carcinoma

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World Journal of Clinical Cases 2019年第1期7卷 49-57页

作者： wei Jiang hong-yan wei Hai-yan Zhang Qiu-Luan Zhuo Department of Ultrasound Shenzhen Nanshan District People’s Hospital

BACKGROUND Cervical lymph node metastasis in papillary thyroid carcinoma(PTC) affects the treatment and prognosis of patients. Ultrasound is a common imaging method for detecting cervical lymph nodes in PTC patients; however, it is not accurate in determining lymph node *** To evaluate the value of contrast-enhanced ultrasound combined with elastography in evaluating cervical lymph node metastasis in *** A total of 94 patients with PTC were recruited. According to pathological results,lymph nodes were divided into two groups: metastatic group(n = 50) and reactive group(n = 63). The routine ultrasound findings, contrast-enhanced ultrasound and elastography data were recorded and compared. Logistic regression was used to generate predictive probability distributions for the diagnosis of lymph node metastasis with different indicators. Receiver operating characteristic curve analysis was used to test the efficacy of contrast-enhanced ultrasound combined with elastography based on routine ultrasound in evaluating PTC cervical lymph node *** The ratio of long diameter/short diameter(L/S) ≤ 2, irregular marginal morphology, missing lymphatic portal, peripheral or mixed blood flow distribution, peak intensity(PI), non-uniform contrast distribution and elasticity score in the metastatic group were significantly higher than those in the reactive group(P < 0.05). L/S ratio, missing lymphatic portal, PI and elasticity score had a significant influence on the occurrence of PTC cervical lymph node metastasis(P< 0.05). Furthermore, the area under the curve(AUC) for lymph node metastasis diagnosed using the combination of PI ratio, elasticity score, missing lymphatic portal and LS was 0.936, which was significantly higher than the AUC for PI ratio alone. The difference was statistically significant(P < 0.05). The fitting equation for the combined diagnosis was logit(P) =-12.341 + 1.482 × L/S ratio + 3.529 ×missing lymphatic portal + 0.392 × PI + 3

关键词： Contrast-enhanced ultrasound Elastography Papillary thyroid cancer Cervical lymph node metastasis

Annular lupus panniculitis on the scalp

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Chinese Medical Journal 2021年第1期134卷 115-116页

作者： Hao Guo hong-wei yan Xing-Hua Gao Jiu-hong Li Department of Dermatology First Hospital of China Medical UniversityShenyangLiaoning 110001China.

To the Editor:A 1-year-old boy presented to our department with progressive linear scalp hair loss that had been present for 1 *** examination revealed an annular alopecic patch of approximately 1.5 cm in width located on right parietal and occipital areas of the scalp[Figure 1A].The lesion was smooth with no erythema or *** patient experienced no other *** medical history and family history were *** investigations including a complete blood count,urinalysis,liver and renal function,immunoglobulin(Ig),erythrocyte sedimentation rate,anti-double-stranded DNA,anti-Sm,anti-Ro/SSA,and anti-La/SSB antibody determinations were all normal or *** C3 component was 0.61 g/L(0.79-1.52 g/L)and the antinuclear antibody was positive(1:80).

关键词： scalp lupus Figure

Electrochemical behavior of different shelled microcapsule composite copper coatings

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International Journal of Minerals,Metallurgy and Materials 2011年第3期18卷 377-384页

作者： Xiu-qing Xu yan-hong Guo wei-ping Li Li-qun Zhu School of Materials Science and Engineering Beihang University Beijing 100191 China

Copper/liquid microcapsule composite coatings with polyvinyl alcohol （PVA）, gelatin or methyl cellulose （MC） as shell materials were prepared by electrodeposition. The influence of shell materials on the corrosion resistance of the composite coatings in 0.1 M H2SO4 was investigated by means of electrochemical techniques, scanning electron microscopy （SEM）, and energy dispersion spectrometry （EDS）. The results show that the participation of microcapsules can enhance the corrosion resistance of the composite coatings compared with the traditional copper layer. Based on the analysis of electrochemical test results, the release ways of microcapsules were deduced. Gelatin and MC as the shell materials of microcapsules are easy to release quickly in the composite coating. On the contrary, the releasing speed of PVA microcapsules is relatively slow due to their characteristics.

关键词： composite coatings shell materials copper microcapsules electrochemical properties corrosion resistance electrodeposition

Quench sensitivity of novel Al-Zn-Mg-Cu alloys containing different Cu contents

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Rare Metals 2020年第12期39卷 1395-1401页

作者： Jin-Sheng Chen Xi-Wu Li Bai-Qing Xiong Yony-An Zhang Zhi-Hui Li hong-wei yan hong-wei Liu Shu-Hui Huang State Key Laboratory of Nonferrous Metals and Processes General Research Institute for Nonferrous MetalsBeijing100088China

The effect of copper content on quench sensitivity in novel Al-Zn-Mg-Cu alloys containing high zinc content was investigated by Jominy end quench *** conductivity and hardness test,temperature collecting,and transmission electron microscopy(TEM)technique were adopted for the properties and microstructure characterization of three alloys with different copper *** results indicate that the electrical conductivity of all three alloys increases with the increase of distance from the quenched end,while the hardness shows an opposite *** the dropping of 10%hardness is defined as the critical evaluation standard of quenching,the depth of quenched layer of AlloysⅠ,Ⅱ,andⅢare 70,55,and 40 mm,*** precipitation behavior on grain boundaries of three alloys is similar except for a little difference in size,while the size of precipitates in grains of AlloyⅢwith higher copper content is larger than those of the other two alloys at the same *** all results,the stability of the supersaturated solid solution of AlloyⅢis lower than those of the other two alloys,meaning that AlloyⅢshows the highest quench *** copper content leads to higher quench sensitivity in novel Al-Zn-Mg-Cu alloys with the same content of magnesium,zinc,and other trace elements.

关键词： Al-Zn-Mg-Cu alloy Copper content Quench sensitivity Jominy end quench test Precipitates

Effect of microstructure evolution on wear resistance of equal molar CoCrFeNi high-entropy alloy

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Rare Metals 2023年第11期42卷 3797-3805页

作者： Hai-Tao Zhang Cheng-Lin Wang Jun-wei Miao Shu-yan Shi Ting-Ju Li hong-wei yan Yong-An Zhang Yi-Ping Lu Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Engineering Research Center of High Entropy Alloy Materials(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Key Laboratory for Light-weight Materials Nanjing Technology UniversityNanjing210009China State Key Laboratory of Nonferrous Metals and Processes GRINM Group Co.Ltd.Beijing100088China General Research Institute for Nonferrous Metals Beijing100088China

Face-centered-cubic high-entropy alloys have excellent ductility and great potential for engineering ***,few studies have reported on the wear behavior under different *** study aimed to investigate the tribological behavior of CoCrFeNi highentropy alloy under different *** wear rate increased with the load,and the main wear behavior was abrasive *** cross-sectional microstructure of worn surface consisted of oxide,nanocrystalline,nanolaminated,and deformation *** the higher loads,the deformation mechanism included dislocation slip and deformation twins,and shear bands also *** was unexpectedly found that the wear rate increased sharply under high load,which was attributed to the formation of shear bands and microcracks in the nanocrystalline *** results successfully revealed the great influence of microstructure evolution on the wear rate,providing theoretical guidance for improving the wear resistance of face-centered-cubic high-entropy alloys in the future.

关键词： High-entropy alloys(HEAs) Microstructure evolution Wear mechanism Shear bands

Experimental study on the bank erosion and interaction with near-bank bed evolution due to fluvial hydraulic force

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International Journal of Sediment Research 2015年第1期30卷 81-89页

作者： Ming-hui YU hong-yan wei Song-bai WU State Key Laboratory of Water Resources and Hydropower Engineering Sciences Wuhan University

Bank erosion is a typical process of lateral channel migration,which is accompanied by vertical bed *** a main sediment source,the failed bank soil may directly cause the increase of sediment concentration and considerable channel evolution in a short *** paper presents an experimental study on non-cohesive and cohesive homogenous bank failure processes,influence of the failed bank soil on bank re-collapse,as well as the interaction between bank failure and near-bank bed evolution due to fluvial hydraulic force.A series of experiments were carried out in a 180° bend rectangular *** results reveal the iteration cycle between bank erosion and bed deformation:undercutting of the riverbank,slip failure of the submerged zone of the bank,as well as cantilever failure of the overhang,failed bank soil staying at bank toe temporarily or hydraulic transportation,exchange between the failed bank soil and bed material,bed material load being re-transported either as bed load or as suspended load,and bed *** as bank failure,the mixing of failed bank soil and bed material is more severe near the curved flow ***,non-cohesive bank failure tends to occur near the water surface while cohesive bank failure near the bank *** non-cohesive dense(sandy) soil,the bank erosion amount and residual amount of failed bank soil on the bed increase with the near-bank velocity or bed *** for cohesive soil,only bank erosion amount follows the above *** results are expected to provide theoretical basis for river management and flood prevention.

关键词： Bank erosion Near-bank bed evolution Hydraulic transport Interaction Flume experiment

Effects of trimetazidine on atrial structural remodeling and platelet activation in dogs with atrial fibrillation

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Chinese Medical Journal 2009年第18期122卷 2180-2183页

作者： HAN wei LI wei-min ZHOU hong-yan HUO hong wei Na DONG Guo CAO Yong ZHOU Guo yanG Shu-sen Department of Cardiology First Clinical College of Harbin Medical University Harbin Heilongjiang 150001 China

Atrial fibrillation （AF） is one of the most common .arrhythmias in clinical practice. AF results in electrophysiological alterations which involve increased atrial effective refractory period and atrial effective refractory period dispersion, reduced rate adaptation of atrial effective refractory period, and slowed atrial conduction. These variances promote their own maintenance-AF begets AF.1 Previous study suggested that Ca^2＋ overload and metabolic derangement contributed to electrophysiological remodeling in AF. However, we did not demonstrate a persistent disturbance in energy metabolism during AF in our previous study,

关键词： atrialfibrillation structural remodeling thrombosis trimetazidine