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Journal of University of Science and Technology Beijing 2005年第4期12卷 335-339页

作者： gaofei liang zhenming xu jianguo li School of Environmental Science and Engineering Shanghai Jiaotong University Shanghai 200240 China

The austenite medium Mn steel modified with controlled additions of Ca, Y, Si were directionally solidified using the vertical Bridgman method to study the effects of Ca（Y）-Si modifier on the solid-liquid （S-L） interface morphology and solute segregation. The interface morphology and the C and Mn segregation of the steel directionally solidified at 6.9 μtrn/s were investigated with an image analysis and a scanning electron microscope equipped with energy dispersive X-ray analysis. The 0.5wt% Ca-Si modified steel is solidified with a planar S-L interface. The interface of the 1.0wt% Ca-Si modified steel is similar to that of the 0.5wt% Ca-Si modified steel, but with larger nodes. The 1.5wt% Ca-Si modified steel displays a cellular growth parttern. The S-L interface morphology of the 0.5wt% Ca-Si＋1.0wt% Y-Si modified Mn steel appears as dendritic interface, and primary austenite dendrites reveal developed lateral branching at the quenched liquid. In the meantime, the independent austenite colonies are formed ahead of the S-L interface. A mechanism involving constitutional supercooling explains the S-L interface evolution. It depends mainly on the difference in the contents of Ca, Y, and Si ahead of the S-L interface. The segregation of C and Mn ahead of the S-L interface enhanced by the modifiers is observed.

关键词： austenite Mn steel modification solid-liquid (S-L) interface morphology solute segregation directional solidification

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抗磨钢的最新进展

特殊钢 2002年第4期23卷 1-7页

作者：梁高飞许振明李建国姜启川上海交通大学材料科学与工程学院上海200030 吉林大学南岭校区

综述了抗磨钢包括奥氏体锰钢、低合金马氏体钢和贝氏体钢的最新研究进展。通过分析各种抗磨钢的组织、性能以及应用工况和环境 ,指出了抗磨钢的发展方向。

关键词：抗磨钢组织性能研究进展

Ambiguous temperature difference in aerodynamic levitation process: Modelling, solving and application

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Journal of Materials Science & Technology 2019年第8期35卷 1636-1643页

作者： xuan Ge Xiaowei xu Qiaodan Hu Wenquan Lu liang Yang Sheng Cao Mingxu Xia jianguo li School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China Shanghai Key Laboratory of Materials Laser Processing and Modification Shanghai Jiao Tong University Shanghai 200240 China Monash Centre for Additive Manufacturing (MCAM) Monash University Clayton VIC 3800 Australia

The aerodynamic levitation provides an efficient technique for the research on thermophysical properties and solidification behavior of refractory materials. However, there is a nonnegligible temperature differences across sample, causing unexpected uncertainty of measurement, such as, thermal expansivity and undercooling limit. We establish thermal filed model with properly simplified boundary condition, and derive quantitative expressions of this ambiguous temperature difference. Here we show that the temperature difference not only related to the average temperature, relative size and thermal conductivity of sample, but significantly influenced by the rotation pattern of sample. A huge temperature differences is almost inevitable when the sample with low thermal conductivity and high melting point is smelted in stationary suspension pattern, however, a drastically reduction of temperature difference can be fulfilled by simply making the sample rotation in up to down pattern. The thermal filed simulation was used to confirm the validity of these theoretical expressions. This work shed light on temperature difference in aerodynamic levitation. Based on this work, one can simply estimate the extent of temperature difference across the sample, and regulated that conveniently if needed, which benefit for novel material preparation and solidification mechanism study based on this technique.

关键词： Solidification Levitation Modelling Temperature difference

Deep Learning and Network Analysis:Classifying and Visualizing Geologic Hazard Reports

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Journal of Earth Science 2024年第4期35卷 1289-1303页

作者： Wenjia li liang Wu Xinde xu Zhong Xie Qinjun Qiu Hao liu Zhen Huang jianguo Chen School of Geography and Information Engineering China University of GeosciencesWuhan430078China Key Laboratory of Geological Survey and Evaluation of Ministry of Education China University of GeosciencesWuhan430078China School of Computer Science China University of GeosciencesWuhan430078China Key Laboratory of Urban Land Resources Monitoring and Simulation Ministry of Natural ResourcesShenzhen518034China Hubei Key Laboratory of Intelligent Vision Based Monitoring for Hydroelectric Engineering China Three Gorges UniversityYichang443002China Wuhan Geomatics Institute Wuhan430074China Faculty of Earth Resources China University of GeosciencesWuhan430074China

If progress is to be made toward improving geohazard management and emergency decision-making,then lessons need to be learned from past geohazard information.A geologic hazard report provides a useful and reliable source of information about the occurrence of an event,along with detailed information about the condition or factors of the *** such reports,however,can be a challenging process because these texts are often presented in unstructured long text formats,and contain rich specialized and detailed *** text classification is commonly used to mine disaster text data in open domains(e.g.,news and microblogs).But it has limitations to performing contextual long-distance dependencies and is insensitive to discourse *** deficiencies are most obviously exposed in long text ***,this paper uses the bidirectional encoder representations from Transformers(BERT),to model long ***,utilizing a softmax layer to automatically extract text features and classify geohazards without manual *** latent Dirichlet allocation(LDA)model is used to examine the interdependencies that exist between causal variables to visualize *** proposed method is useful in enabling the machine-assisted interpretation of text-based ***,it can help users visualize causes,processes,and other geohazards and assist decision-makers in emergency responses.

关键词： geologic hazard network analysis latent dirichlet allocation text classification deep learning

Serum from Acute-on-chronic liver Failure Patients May Affect Mesenchymal Stem Cells Transplantation by Impairing the Immunosuppressive Function of Cells

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Journal of Clinical and Translational Hepatology 2021年第4期9卷 503-513页

作者： Yongyuan Zheng Shu Zhu Xingrong Zheng Wenxiong xu xuejun li jianguo li Zhiliang Gao Chan Xie liang Peng Department of Infectious Diseases The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongChina Guangdong Province Key Laboratory of liver Disease Research The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongChina

Background and Aims:The safety and efficacy of mesenchymal stem cells(MSCs)in the treatment of acute-onchronic liver failure(ACLF)have been ***,the impact of the pathological ACLF microenvironment on MSCs is less well *** study was designed to explore the changes in the functional properties of MSCs exposed to ACLF ***:MSCs were cultured in the presence of 10%,30%and 50%serum concentrations from ACLF patients and healthy ***,the cell morphology,phenotype,apoptosis and proliferation of MSCs were evaluated,including the immunosuppressive ***,mRNA sequencing analysis was used to identify the molecules and pathways involved in MSC functional changes in the context of ***:In the presence of ACLF serum,MSC morphology significantly changed but phenotype did ***,MSC proliferation activity was weakened,while the apoptosis rate was lightly *** importantly,the immunosuppressive function of MSCs was enhanced in a lowconcentration serum environment but transformed into a proinflammatory response in a high-concentration serum *** sequencing indicated that 10%serum concentration from ACLF patients mediated the PI3K-Akt pathway to enhance the anti-inflammatory effect of MSCs,while the 50%serum concentration from ACLF patients promoted the conversion of MSCs into a proinflammatory function by affecting the cell ***:The 50%ACLF serum concentration is more similar to the environment in the human body,which means that direct peripheral blood intravenous infusion of MSCs may reduce the effect of *** treatments of plasma exchange to reduce harmful substances in serum may promote MSCs to exert a stronger anti-inflammatory effect.

关键词： Mesenchymal stem cells Acute-on-chronic liver failure Immu-nomodulatory Cell therapy Microenvironment

维普期刊数据库评论

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Au液异质形核价电子模型与基底触媒效用

稀有金属材料与工程 2005年第10期34卷 1558-1561页

作者：梁高飞宋长江刘向阳许振明李建国上海交通大学

异质形核是凝固领域的核心问题之一,界面共格对应理论无法解释金液滴异质形核过程中ZrC,TiC,TiN等基底的触媒作用优于TiO的现象。利用余氏“固体与分子经验电子理论”以及程氏“改进的TFD模型中表面电子密度相等的边界条件”,分析表明... 详细信息

异质形核是凝固领域的核心问题之一,界面共格对应理论无法解释金液滴异质形核过程中ZrC,TiC,TiN等基底的触媒作用优于TiO的现象。利用余氏“固体与分子经验电子理论”以及程氏“改进的TFD模型中表面电子密度相等的边界条件”,分析表明界面共格对应并不是有效触媒基底的本质要求;在Tillen静电作用理论基础上,建立了Au液凝固异质形核价电子模型与基底触媒效用判据,据此分析了ZrC,TiC,TiN,TiO基底对Au液滴异质形核的触媒效用,与实验结果吻合。

关键词：金异质形核凝固触媒价电子

A simple simulator and method for measuring transient interfacial heat transfer in the strip casting process

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Baosteel Technical Research 2009年第1期3卷 32-34页

作者： ZHANG Wei liang gaofei WANG Chengquan YU Yan FANG Yuan li jianguo School of Materials Science ＆ Engineering Shanghai Jiaotong University Shanghai 200240 China Advanced Technology Division Baosteel Research Institute Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China

This study presents a simple simulator for measuring the transient interfacial heat transfer between the molten steel and the copper casting roll for strip casting. The calculation principle of the heat flux is introduced in detail. Results show that the heat flux reaches the peak value of 9 MW/m^2 ,and decreases rapidly to 4 MW/m^2, and then fluctuates within the range of 2 MW/m^2 to 5 MW/m2. It agrees with the previous study. It also indicates the simulator can be effectively used to analyze the heat transfer during strip casting.

关键词： strip casting heat transfer heat flux

Establishment of primary cultures of craniopharyngioma cells

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Neural Regeneration Research 2012年第8期7卷 601-605页

作者： Hao liu liang liu Zhiyong liu Qiang li Chao You jianguo xu Department of Neurosurgery West China Hospital Sichuan University Chengdu 610041 Sichuan Province China Department of Neurosurgery Affiliated Hospital of Luzhou Medical College Luzhou 646000 Sichuan Province China

Craniopharynigoma samples were collected from 36 patients. Out of the 36 samples, 29 achieved successful sub-culturing, with a success rate of 80.6%. Immunohistochemistry staining showed that cytokeratin-7 was positively expressed in the cytomembrane and cytoplasm of craniopharyngioma cells at 6-8 passages, confirming that all cultured cells were squamous epithelial cells. The doubling time of craniopharyngioma cells was 3 days, as confirmed by the 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide assay. In this study, craniopharyngioma cells cultured in vitro were established; however, establishment of immortalized craniopharyngioma cell lines requires further research.

关键词： craniopharyngioma cytokeratin-7 primary culture culture in vitro cell line

钇基重稀土合金变质团球γ+(Fe,Mn)_3C共晶体增强奥氏体钢基自生复合材料

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中国稀土学报 2002年第z2期20卷 145-147页

作者：梁高飞许振明姜启川李建国上海交通大学材料科学与工程学院上海200030 吉林大学材料学院吉林长春130025

采用Y基重稀土合金变质处理钢液,通过影响钢液中C,Mn等合金元素的偏析和相的生成,从而控制钢液凝固组织,在铸态下获得团球γ+(Fe,Mn)3C共晶体增强奥氏体钢基自生复合材料(AMGE)。Y基重稀土合金增大C,Mn元素的偏析,使凝固后期初生奥氏体... 详细信息

采用Y基重稀土合金变质处理钢液,通过影响钢液中C,Mn等合金元素的偏析和相的生成,从而控制钢液凝固组织,在铸态下获得团球γ+(Fe,Mn)3C共晶体增强奥氏体钢基自生复合材料(AMGE)。Y基重稀土合金增大C,Mn元素的偏析,使凝固后期初生奥氏体枝晶间小熔池中的成分达到共晶反应区,在非平衡凝固条件下生成γ+(Fe,Mn)3C共晶体。干摩擦磨损试验表明,在中、低载工况下AMGE的磨损量比基体合金奥氏体中锰钢低1～3倍,并且AMGE发生严重磨损时的载荷高于基体合金。

关键词：稀土团球共晶体自生复合材料 Y基重稀土耐磨性

磷脂酰肌醇蛋白聚糖-3在乳腺癌组织中的表达及其意义

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中国普通外科杂志 2011年第11期20卷 1216-1220页

作者：周栋徐亮李建国江苏省常熟市中医院(新区医院)普通外科江苏常熟215500

目的探讨磷脂酰肌醇蛋白聚糖-3(glypican-3)在乳腺癌组织中的表达及其与乳腺癌临床病理参数的关系。方法采用RT-PCR方法检测52例乳腺癌组织及其癌旁组织中glypican-3基因的表达,计算其阳性率;并用Western blot方法检测该基因在乳腺癌组... 详细信息

目的探讨磷脂酰肌醇蛋白聚糖-3(glypican-3)在乳腺癌组织中的表达及其与乳腺癌临床病理参数的关系。方法采用RT-PCR方法检测52例乳腺癌组织及其癌旁组织中glypican-3基因的表达,计算其阳性率;并用Western blot方法检测该基因在乳腺癌组织及其癌旁组织中的蛋白表达。结果 glypican-3 mRNA在乳腺癌组织中表达率明显低于癌旁组织(P0.05)。glypican-3蛋白在乳腺癌组织中表达亦明显低于癌旁正常组织(P<0.05),在有淋巴结转移者中的表达量明显低于无淋巴结转移者(P<0.05),癌组织分化程度越低,glypican-3蛋白的表达量越低(P<0.05)。结论 glypican-3在乳腺癌组织中的低表达可能与乳腺癌的发生发展及侵袭转移有关。

关键词：乳腺肿瘤/病理学磷脂酰肌醇蛋白聚糖-3 RT-PCR Western blot