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Three dimensional phase-field simulation for non-isothermal binary alloy solidification: Comparison with LKT theory

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China Foundry 2023年第6期20卷 545-552页

作者： Jun Wu Ting-yi Liu Gui-chao Hu Rong Ma xiao-peng Zhang Yu-fei Li Chao Luo Institute of Materials China Academy of Engineering PhysicsJiangyou 621907SichuanChina

Using the advanced algorithm combining parallel computing,adaptive mesh re-griding and multigrid methods,quantitative 3D phase-field simulations of non-isothermal solidification of binary alloy were carried *** 3D phase-field simulation results were compared with the analytical LKT(Lipton,Kurz and Trivedi)*** comparison,the simulation and analytical results for 2D cases were also *** 3D phase-field simulation results support the transport portion of the LKT ***,the tip radius and tip velocity predicted by the simulations are not in good agreement with the LKT theory over the whole range of *** stability parameter calculated from phase-field simulations varies significantly with the Peclet number,indicating that the stability criterion,which assumes that the stability parameter is constant,is invalid.

关键词： 3D phase-field non-isothermal solidification free dendritic growth

Dual-phase synergistic deformation characteristics and strengthening mechanism of AlCoCrFeNi_(2.1) eutectic high entropy alloy fabricated by laser powder bed fusion

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Journal of Materials Science & Technology 2023年第19期150卷 75-85页

作者： Xu Tang Hao Zhang Zhengwang Zhu peng Xue Lihui Wu Fengchao Liu Dingrui Ni Bolv xiao Zongyi Ma Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Eutectic high entropy alloy(EHEA)possesses promising prospects for industrial application due to its controllable and near-equilibrium dual-phase *** to the advantages of high material utiliza-tion,efficient production,and design freedom,the laser powder bed fusion(LPBF)technique provides a new path to prepare EHEA components with complex structure and excellent *** this study,near fully dense AlCoCrFeNi_(2.1) samples were obtained by adjusting the process parameters of ***-sidering the balling phenomenon and powder splashing during the LPBF process,laser remelting was selected as an optimized scanning strategy to further improve the forming quality of *** microstructure of remelted AlCoCrFeNi_(2.1) sample exhibited regular eutectic lamellae consisting of nano-scale face-centered-cubic(FCC)and B2 phases,in which the FCC phase accounted for a higher *** investigating the tensile behavior and deformation mechanism,it was revealed that the ultrafine eu-tectic lamellae could induce a strong dual-phase synergistic strengthening,thereby significantly improv-ing the strength of the *** with the vacuum induction melted(VIM)sample,the remelted sample showed a 54%increase in ultimate tensile strength(UTS-1518 MPa)and a 130%increase in yield strength(YS-1235 MPa)with reasonable *** study indicates that by combining the design and manufacturing freedom of LPBF with the EHEA,it is expected to fabricate high-property 3D EHEA parts,expanding the application field of EHEA.

关键词： Laser powder bed fusion Remelting Eutectic high entropy alloy Microstructure Deformation mechanism

Microstructure and shear properties evolution of Mn-doped SAC solder joint under isothermal aging

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Journal of Iron and Steel Research International 2023年第8期30卷 1650-1660页

作者： Cheng-ming Li Shu-jin Chen Shan-shan Cai Ju-bo peng xiao-jing Wang Ying-wu Wang School of Material Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003JiangsuChina R&D Center Yunnan Tin Group(Holding)Co.Ltd.Kunming 650000YunnanChina Modern School of Engineering Yunnan UniversityKunming 650091YunnanChina

The effects of Mn addition(0.005,0.01,0.03,0.05,and 0.07 wt.%)on microstructure,shear mechanical behavior,and interfacial thermal stabilities of SAC305 joints were investigated under isothermal aging temperatures of 170 C with different aging time(0,250,500,and 750 h).It is found that Mn addition can increase fracture energy of joints without decreasing the shear *** the microstructures have transformed from the eutectic net-like structure in SAC305 solder joints into the structures based onβ-Sn matrix with intermetallic compounds(IMCs)*** doping 0.07 wt.%Mn,the Cu_(6)Sn_(5) growth along the SAC305/Cu interface during thermal aging can be inhibited to some *** isothermal aging at 170°C,the maximum shear force of solder joint decreases continuously with aging time increasing,while the fracture energy rises first and then decreases,reaching the maximum at 500 h compared by that with the microstructure ***_(3)Sn growth between Cu_(3)Sn_(5)/Cu interface has been retarded most at the aging time of 250 h with 0.07 wt.%Mn-doped *** the aging time prolonging,the inhibition effect of Mn on CusSn IMC layer becomes *** strengthening effect of Mn can be explained by precipitation strengthening,and its mechanical behavior can be predicted by particle strengthening model proposed by Orowan.

关键词： SAC305 solder Mn doping Shear mechanical behavior Isothermal aging Interfacial intermetallic compound

A semi-analytical method for the analysis of pile-supported embankments

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第11期13卷 888-894页

作者： Wan-huan ZHOU Ren-peng CHEN Lin-shuang ZHAO Zheng-zhong XU Yun-min CHEN Department of Civil and Environmental Engineering University of Macao Macao China MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Department of Civil Engineering Zhejiang University Hangzhou 310058 China

In this paper,a semi-analytical method for the analysis of pile-supported embankments is *** mathematic model describes the cooperative behavior of pile,pile cap,foundation soil,and embankment *** on Terzaghi's 1D consolidation theory of saturated soil,the consolidation of foundation soil is *** embankments with two different types of piles:floating piles and end-bearing piles are investigated and *** results of axial force and skin friction distributions along the pile and the settlements of pile-supported embankments are *** is found that it takes a longer time for soil consolidation in the embankment with floating piles,compared with the case using end-bearing *** differential settlement between the pile and surrounding soil at the pile top is larger for the embankment with end-bearing piles,compared with the case of floating piles.

关键词： Pile-supported embankment Soil arching Load transfer Equal settlement plane Soft soils

A hybrid dynamic programming-rule based algorithm for real-time energy optimization of plug-in hybrid electric bus

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Science China(Technological Sciences) 2014年第12期57卷 2542-2550页

作者： ZHANG Ya Hui JIAO xiao Hong LI Liang YANG Chao ZHANG Li peng SONG Jian Institute of Electric Engineering Yanshan University State Key Laboratory of Automotive Safety and Energy Tsinghua University

The optimization of the control strategy of a plug-in hybrid electric bus(PHEB) for the repeatedly driven bus route is a key technique to improve the fuel economy. The widely used rule-based(RB) control strategy is lacking in the global optimization property, while the global optimization algorithms have an unacceptable computation complexity for real-time application. Therefore, a novel hybrid dynamic programming-rule based(DPRB) algorithm is brought forward to solve the global energy optimization problem in a real-time controller of PHEB. Firstly, a control grid is built up for a given typical city bus route, according to the station locations and discrete levels of battery state of charge(SOC). Moreover, the decision variables for the energy optimization at each point of the control grid might be deduced from an off-line dynamic programming(DP) with the historical running information of the driving cycle. Meanwhile, the genetic algorithm(GA) is adopted to replace the quantization process of DP permissible control set to reduce the computation burden. Secondly, with the optimized decision variables as control parameters according to the position and battery SOC of a PHEB, a RB control is used as an implementable controller for the energy management. Simulation results demonstrate that the proposed DPRB might distribute electric energy more reasonably throughout the bus route, compared with the optimized RB. The proposed hybrid algorithm might give a practicable solution, which is a tradeoff between the applicability of RB and the global optimization property of DP.

关键词： plug-in hybrid electric bus (PHEB) control strategy optimization dynamic programming (DP) genetic algorithm (GA) city bus route

Successful treatment of acute symptomatic extensive portal venous system thrombosis by 7-day systemic thrombolysis

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World Journal of Gastrointestinal Surgery 2022年第9期14卷 1082-1088页

作者： Fang-Bo Gao Le Wang Wen-Xiu Zhang xiao-Dong Shao xiao-zhong Guo Xing-Shun Qi Department of Gastroenterology General Hospital of Northern Theater CommandShenyang 110840Liaoning ProvinceChina Postgraduate College Shenyang Pharmaceutical UniversityShenyang 110016Liaoning ProvinceChina

Acute portal venous system thrombosis(PVST)can cause acute mesenteric ischemia and even intestinal infarction,which are potentially fatal,and requires recanalization in a timely ***,we report a 56-year-old man with acute non-cirrhotic symptomatic extensive PVST who achieved portal vein recanalization after systemic thrombolysis combined with ***,anticoagulation with enoxaparin sodium for 4 d was ineffective,and then systemic thrombolysis for 7 d was *** that,his abdominal pain completely disappeared,and portal vein system vessels became gradually ***-term anticoagulation therapy was *** conclusion,7-d systemic thrombolysis may be an effective and safe choice of treatment for acute symptomatic extensive PVST which does not respond to anticoagulation therapy.

关键词： Portal vein Mesenteric vein Thrombosis Thrombolysis Anticoagulation Deep vein thrombosis

Improved prescription of taohechengqi-tang alleviates D-galactosamine acute liver failure in rats

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World Journal of Gastroenterology 2016年第8期22卷 2558-2565页

作者： Yang Zhang Jian-Xing Luo xiao-Yu Hu Fang Yang Sen zhong Wu Lin Department of Infectious Diseases Affiliated Hospital of Chengdu University of Traditional Chinese Medicine Department of Neurology Affiliated Hospital of Chengdu University of Traditional Chinese Medicine Department of Clinical Medicine Chengdu University of Traditional Chinese Medicine

AIM: To investigate the hepatoprotective effect of improved prescription of Taohechengqi-tang (IPTT) against acute liver failure (ALF) in ***: Seventy specific pathogen free male Wistar rats were randomly divided into four groups: control group (normal rats, n = 10), ALF group (ALF model, n = 20), Stronger Neo-Minophagen C (SNMC) group (ALF model + SNMC, n = 20), and IPTT group (ALF model + IPTT, n = 20). The ALF model group was administered an intraperitoneal injection of D-galactosamine (1.4 g/kg), and the control group received normal saline intraperitoneally. The SNMC and IPTT groups were treated with SMMC (15.6 mg/kg) or IPTT (28.6 g/kg) by gavage at 24 h intervals, and the ALF and control groups were treated with normal saline. At 36 h after injection, serum alanine aminotransferase, aspartate aminotransferase, total bilirubin, albumin, and cholinesterase and prothrombin time were determined, and liver histopathological scores were observed by microscopy after hematoxylin and eosin staining. mRNA expression of high mobility group box (HMGB) 1, toll-like receptor (TLR) 4, nuclear factor kappa B (NF-κB) and caspase-3 were analyzed via fluorescence quantitative reverse transcriptase polymerase chain reaction. Proliferating cell nuclear antigen (PCNA) immunohistochemistry in liver tissue was also ***: D-galactosamine notably decreased the biochemical and coagulation profiles in serum. IPTT not only improved liver function and histopathology but also normalized the gene expression levels in liver tissue. Compared with the model group, in the IPTT and SNMC groups, HMGB1 mRNA/β-actin (0.06 ± 0.03, 0.11 ± 0.04 vs 0.25 ± 0.04, P < 0.05); TLR4 mRNA/β-actin (0.07 ± 0.02, 0.22 ± 0.08 vs 0.41 ± 0.22, P < 0.05); NF-κB mRNA/β-actin (0.74 ± 0.41, 1.78 ± 0.64 vs 2.68 ± 1.35, P < 0.05); and caspase-3 mRNA/β-actin

关键词： Acute liver failure Traditional Chinese medicine Taohechengqi-tang High mobility group box 1 Inflammation

公路交通发展背景下西部民族地区人才培养模式构建与实践

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教育教学论坛 2024年第21期 89-92页

作者：陈子璇张久鹏赵晓康张晔长安大学公路学院陕西西安710064

西部民族地区作为共建“一带一路”设施联通的重点领域,加快与境外国际通道的互联互通,提升对区域发展和国家战略的支撑能力,迫切需要培养扎根本地、胜任复杂工程问题的少数民族公路交通人才。结合长安大学少数民族人才培养模式构建与实... 详细信息

西部民族地区作为共建“一带一路”设施联通的重点领域,加快与境外国际通道的互联互通,提升对区域发展和国家战略的支撑能力,迫切需要培养扎根本地、胜任复杂工程问题的少数民族公路交通人才。结合长安大学少数民族人才培养模式构建与实践,提出了面向少数民族学生的“思政—通识—专业”课程协同育人体系,形成了适应少数民族学生的学习基础和语言能力的课程体系、教学模式和学业“结对帮扶”机制,健全完善了校地联动、产教协同育人机制。铸牢少数民族学生的中华民族共同体意识,强化交通强国建设的使命担当,夯实少数民族学生的理论知识和专业能力基础,提升少数民族学生对公路交通复杂工程问题解决能力和科技创新能力。

关键词：西部地区发展少数民族人才培养公路交通

Changes in paddy cropping system enhanced economic profit and ecological sustainability in central China

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Journal of Integrative Agriculture 2022年第2期21卷 566-577页

作者： ZHOU Yong YAN xiao-yuan GONG Song-ling LI Cheng-wei ZHU Rong ZHU Bo LIU Zhangyong WANG xiao-long CAO peng Hubei Collaborative Innovation Centre for Grain Industry/College of Agriculture Yangtze UniversityJingzhou 434025P.R.China Engineering Research Center of Ecology and Agricultural Use of Wetland of Ministry of Education Yangtze UniversityJingzhou 434025P.R.China College of Agriculture South China Agricultural UniversityGuangzhou 510642P.R.China Agricultural Technology Extension Station of Hubei Province Wuhan 430070P.R.China

In China,the traditional early and late season double rice(DR)system is declining accompanied by the fast increase of two newly developed cropping systems:ratoon rice(RR)and rice-crawfish(RC).Three methodologies:economic analysis,emergy evaluation and life cycle assessment(LCA)were employed to evaluate the economics and sustainability of this paddy cropping system *** analysis indicated that the income and profit of the RC system were far larger than those of RR and *** income to costs ratio of RR and RC increased by 25.5 and 122.7%compared with that of DR,*** had the highest emergy input thanks to increasing irrigation water,electricity,juvenile crawfish and forage input while RR showed a lower total emergy and nonrenewable emergy input,such as irrigation water,electricity,fertilizers and pesticides than *** environmental loading ratios decreased by 16.7-50.4%when cropping system changed from DR to RR or from DR to RC while the emergy sustainability indexes increased by 22.6-112.9%.The life cycle assessment indicated lower potential environmental impacts of RR and RC,whose total environmental impact indexes were 35.0-61.0%lower than that of *** yield of RR was comparable with that of DR in spite of less financial and emergy input of RR,but RC had a much lower grain yield(a 53.6%reduction compared to DR).These results suggested that RR is a suitable cropping system to achieve the food security,economic and environmental goals.

关键词： paddy cropping system changes economic analysis emergy evaluation LCA food security central China