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连铸方坯热应力模型的研究及应用

东北大学学报（自然科学版） 2009年第10期30卷 1445-1448页

作者：马交成祖陵宇刘文红谢植东北大学机械工程与自动化学院辽宁沈阳110004 东北大学信息科学与工程学院辽宁沈阳110004

为了减少不恰当连铸二冷操作导致的铸坯内部裂纹等缺陷,在凝固传热模型验证的基础上建立了方坯二维弹塑性应力模型.通过此模型计算了水量优化前后铸坯应力分布情况,获得了铸坯在二冷区的应力分布规律.分析了影响连铸坯内部裂纹的因素,... 详细信息

为了减少不恰当连铸二冷操作导致的铸坯内部裂纹等缺陷,在凝固传热模型验证的基础上建立了方坯二维弹塑性应力模型.通过此模型计算了水量优化前后铸坯应力分布情况,获得了铸坯在二冷区的应力分布规律.分析了影响连铸坯内部裂纹的因素,提出预防热裂纹产生的措施,为研究二冷对铸坯质量的影响提供了理论基础,并为优化二冷水量改善铸坯质量提供了依据.

关键词：连铸传热凝固应力模型有限元内部裂纹

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方坯连铸三维动态凝固模型有限元模拟

系统仿真学报 2009年第17期21卷 5379-5383,5387页

作者：祖凌宇孟红记谢植东北大学信息科学与工程学院沈阳110004

方坯连铸三维动态凝固模型能够真实反映工艺参数变化时的温度动态调节过程,考虑数值求解计算量大和计算速度慢等难题,改变铸坯横断面节点和单元网格的人工生成模式为自动生成模式,采用密度函数和网格质量评价函数,控制节点和单元网格及... 详细信息

方坯连铸三维动态凝固模型能够真实反映工艺参数变化时的温度动态调节过程,考虑数值求解计算量大和计算速度慢等难题,改变铸坯横断面节点和单元网格的人工生成模式为自动生成模式,采用密度函数和网格质量评价函数,控制节点和单元网格及优化网格形状以保证网格划分的合理性;引入单元节点商和节点商及节点最大最小编号为约束条件的优化方法优化节点编号,缩小带宽节约存储空间。仿真结果表明,动态凝固模型采用有限元网格自动生成和优化方法以后具有更高的计算速度和计算精度。

关键词：凝固模型有限元网格自动生成优化

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城市轻轨车辆用螺杆空气压缩机组的设计

电力机车与城轨车辆 2005年第3期28卷 23-25页

作者：俎玉玲北京中铁工建筑设计院北京100038

从螺杆空气压缩机组的性能、结构等方面介绍了城市轻轨车辆用小排量螺杆空气压缩机的设计情况,同时介绍了其在轻轨车辆上的应用情况。

关键词：城市轻轨螺杆空气压缩机组设计应用

Acute and chronic excitotoxicity in ischemic stroke and late-onset Alzheimer's disease

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Neural Regeneration Research 2025年第7期20卷 1981-1988页

作者： Shan Ping yu Emily Choi Michael QJiang ling Wei Department of Anesthesiology Emory University School of MedicineAtlantaGAUSA Center for Visual and Neurocognitive Rehabilitation Atlanta Veterans Affairs Medical CenterDecaturGAUSA

Stroke and Alzheimer's disease are common neurological disorders and often occur in the same *** comorbidity of the two neurological disorders represents a grave health threat to older *** review presents a brief background of the development of novel concepts and their clinical *** activity of glutamatergic N-methyl-D-aspartate receptors and N-methyl-D-aspartate receptor-mediated Ca^(2+)influx is critical for neuronal *** ischemic insult induces prompt and excessive glutamate release and drastic increases of intracellular Ca^(2+)mainly via N-methyl-D-aspartate receptors,particularly of those at the extrasynaptic *** Ca^(2+)-evoked neuronal cell death in the ischemic core is dominated by necrosis within a few hours and days known as acute ***,mild but sustained Ca^(2+)increases under neurodegenerative conditions such as in the distant penumbra of the ischemic brain and early stages of Alzheimer's disease are not immediately toxic,but gradually set off deteriorating Ca^(2+)-dependent signals and neuronal cell loss mostly because of activation of programmed cell death *** on the Ca^(2+)hypothesis of Alzheimer's disease and recent advances,this Ca^(2+)-activated“silent”degenerative excitotoxicity evolves from years to decades and is recognized as a unique slow and chronic *** N-methyl-D-aspartate receptor subunit GluN3A,primarily at the extrasynaptic site,serves as a gatekeeper for the N-methyl-D-aspartate receptor activity and is neuroprotective against both acute and chronic *** stroke and Alzheimer's disease,therefore,share an N-methyl-D-aspartate receptor-and Ca^(2+)-mediated mechanism,although with much different time *** is thus proposed that early interventions to control Ca^(2+)homeostasis at the preclinical stage are pivotal for individuals who are susceptible to sporadic late-onset Alzheimer's disease and Alzheimer's disease-related

关键词： Ca^(2+)hypothesis cognitive deficits hyperactivity late-onset Alzheimer's disease neurodegeneration N-methyl-D-aspartate receptors N-methyl-D-aspartate receptor subunits pathogenesis preventive treatment

Drosophila models used to simulate human ATP1A1 gene mutations that cause Charcot-Marie-Tooth type 2 disease and refractory seizures

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Neural Regeneration Research 2025年第1期20卷 265-276页

作者： Yao yuan lingqi yu Xudong Zhuang Dongjing Wen Jin He Jingmei Hong Jiayu Xie Shengan ling Xiaoyue Du Wenfeng Chen Xinrui Wang Institute of Life Sciences College of Biological Science and EngineeringFuzhou UniversityFuzhouFujian ProvinceChina NHC Key Laboratory of Technical Evaluation of Fertility Regulation for Non-human Primate(Fujian Maternity and Child Health Hospital) FuzhouFujian ProvinceChina Medical Research Center Fujian Maternity and Child Health HospitalCollege of Clinical Medicine for Obstetrics&Gynecology and PediatricsFujian Medical UniversityFuzhouFujian ProvinceChina Department of Neurology and Institute of Neurology of The First Affiliated Hospital Institute of Neuroscienceand Fujian Key Laboratory of Molecular NeurologyFujian Medical UniversityFuzhouFujian ProvinceChina

Certain amino acids changes in the human Na^(+)/K^(+)-ATPase pump,ATPase Na^(+)/K^(+)transporting subunit alpha 1(ATP1A1),cause Charcot-Marie-Tooth disease type 2(CMT2)disease and refractory *** develop in vivo models to study the role of Na^(+)/K^(+)-ATPase in these diseases,we modified the Drosophila gene homolog,Atpα,to mimic the human ATP1A1 gene mutations that cause *** located within the helical linker region of human ATP1A1(I592T,A597T,P600T,and D601F)were simultaneously introduced into endogenous Drosophila Atpαby CRISPR/Cas9-mediated genome editing,generating the Atpα^(TTTF)*** addition,the same strategy was used to generate the corresponding single point mutations in flies(Atpα^(I571T),Atpα^(A576T),Atpα^(P579T),and Atpα^(D580F)).Moreover,a deletion mutation(Atpα^(mut))that causes premature termination of translation was generated as a positive *** these alleles,we found two that could be maintained as homozygotes(Atpα^(I571T)and Atpα^(P579T)).Three alleles(Atpα^(A576T),Atpα^(P579)and Atpα^(D580F))can form heterozygotes with the Atpαmut *** found that the Atpαallele carrying these CMT2-associated mutations showed differential phenotypes in *** heterozygous for Atpα^(TTTF)mutations have motor performance defects,a reduced lifespan,seizures,and an abnormal neuronal *** Drosophila models will provide a new platform for studying the function and regulation of the sodium-potassium pump.

关键词： ATP1A1 Atpα bang-sensitive paralysis Charcot-Marie-Tooth disease type 2 CRISPR/Cas9 homology-directed repair Na^(+)/K^(+)-ATPase point mutation seizures sodium pump

Literature study on traditional Chinese medicine syndromes after renal transplantation

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World Journal of Transplantation 2025年第1期15卷 150-155页

作者： yun-Peng Guo ling-Xue Bao yu-Yang Wang Quan Wen Gai Hang Bo Chen Tongliao Clinical Medical College Inner Mongolia Medical UniversityTongliao 028000Inner Mongolia Autonomous RegionChina Department of Urology Tongliao People's HospitalTongliao 028000Inner Mongolia Autonomous RegionChina

BACKGROUND Kidney transplantation is the most effective means to treat patients with renal failure,but its postoperative problems such as rejection reactions,immunosuppressant poisoning,chronic transplant kidney nephropathy,*** have not been effectively *** study searched for literature on traditional Chinese medicine(TCM)syndromes after kidney transplantation in China,conducted statistical analysis of the results,and sought to identify the underlying *** To understand the TCM syndromes after renal transplantation and associated rules and provide a theoretical basis for further clinical *** The literature pertaining to TCM syndromes in renal transplantation,published in the China National Knowledge Infrastructure,Wanfang database,and WIP database from 1970 to 2021,was meticulously searched and comprehensively and statistically *** Following the established inclusion and exclusion criteria,13 studies were selected for ***-renal transplantation,no significant discrepancy was noted among the groups based on the location of TCM ***,when categorized according to TCM pathogenic factors,the groups with spleen and kidney yang deficiency,as well as liver and kidney yin deficiency,exhibited a statistically significant difference in the *** Currently,the research on TCM syndromes pertaining to renal transplantation is in its nascent *** is imperative to conduct a multicentric,large-scale survey of TCM syndromes subsequent to renal transplantation in the ensuing years.

关键词： Kidney transplantation Syndrome Literature analysis Traditional Chinese medicine Systematic review

The limit analysis in soil and rock:a mature discipline of geomechanics

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第11期8卷 1712-1724页

作者： CHEN zu-yu China Institute of Water Resources and Hydropower Research Beijing 100044 China MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang University Hangzhou 310027 China

The solution of a slope stability problem can be approached by its least upper-bound and maximum lower-bound with high accuracy. The limit equilibrium methods that employ vertical slices imply a lower bound of the factor of safety. It has been successfully extended to the area of active earth pressure analysis that accounts for different input of locations of earth pressure applications. Those methods that employ slices with inclined interfaces give an upper-bound approach to the stability analysis. It enjoys a sound mechanical background and is able to provide accurate solutions of soil plasticity. It has been successfully extended to the area of bearing capacity analysis in which various empirical coefficients are no longer necessary. The 3D upper- and lower-bound methods under this framework have been made possible and show great potential for solving various engineering problems.

关键词： Limit analysis Geomechanics Slope stability problem Limit equilibrium method

miRNA-21-5p is an important contributor to the promotion of injured peripheral nerve regeneration using hypoxia-pretreated bone marrow-derived neural crest cells

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Neural Regeneration Research 2025年第1期20卷 277-290页

作者： Meng Cong Jing-Jing Hu Yan yu Xiao-Li Li Xiao-Ting Sun Li-Ting Wang Xia Wu ling-Jie Zhu Xiao-Jia Yang Qian-Ru He Fei Ding Hai-Yan Shi School of Medicine Nantong UniversityNantongJiangsu ProvinceChina Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education and Coinnovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Physiology Jiangsu Health Vocational CollegeNanjingJiangsu ProvinceChina Department of Pathology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina

Our previous study found that rat bone marrow–derived neural crest cells(acting as Schwann cell progenitors)have the potential to promote long-distance nerve ***-based therapy can enhance peripheral nerve repair and regeneration through paracrine bioactive factors and intercellular ***,the complex contributions of various types of soluble cytokines and extracellular vesicle cargos to the secretome remain *** investigate the role of the secretome and extracellular vesicles in repairing damaged peripheral nerves,we collected conditioned culture medium from hypoxia-pretreated neural crest cells,and found that it significantly promoted the repair of sensory neurons damaged by oxygen-glucose *** mRNA expression of trophic factors was highly expressed in hypoxia-pretreated neural crest *** performed RNA sequencing and bioinformatics analysis and found that miR-21-5p was enriched in hypoxia-pretreated extracellular vesicles of neural crest ***,to further clarify the role of hypoxia-pretreated neural crest cell extracellular vesicles rich in miR-21-5p in axonal growth and regeneration of sensory neurons,we used a microfluidic axonal dissociation model of sensory neurons in vitro,and found that hypoxia-pretreated neural crest cell extracellular vesicles promoted axonal growth and regeneration of sensory neurons,which was greatly dependent on loaded ***,we constructed a miR-21-5p-loaded neural conduit to repair the sciatic nerve defect in rats and found that the motor and sensory functions of injured rat hind limb,as well as muscle tissue morphology of the hind limbs,were obviously *** findings suggest that hypoxia-pretreated neural crest extracellular vesicles are natural nanoparticles rich in ***-21-5p is one of the main contributors to promoting nerve regeneration by the neural crest cell *** helps to explain the mechanism of action of the secretome and e

关键词： axotomy cell-free therapy conditioned medium extracellular vesicles hypoxic preconditioning microRNA oxygen-glucose deprivation peripheral nerve injury Schwann cell precursors

A cellulose-based lithium-ion battery separator with regulated ionic transport and high thermal stability for extreme environments

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Nano Research 2025年第1期18卷 315-322页

作者： Kun-Peng Yang Song Xie Zi-Meng Han Hao-Cheng Liu Chong-Han Yin Wen-Bin Sun Zhang-Chi ling Huai-Bin Yang De-Han Li Qing-Fang Guan Shu-Hong yu Department of Chemistry New Cornerstone Science LaboratoryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsDivision of Nanomaterials&ChemistryHefei National Research Center for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China Institute of Innovative Materials Department of Materials Science and EngineeringDepartment of ChemistrySouthern University of Science and TechnologyShenzhen 518055China

Separators play a critical role in lithium-ion ***,the restrictions of thermal stability and inferior electrical performance in commercial polyolefin separators significantly limit their applications under harsh ***,we report a cellulose-assisted self-assembly strategy to construct a cellulose-based separator massively and *** an ultrahigh ionic conductivity in electrolytes of 3.7 mS·cm^(-1) and the ability to regulate ion transport,the obtained separator is a promising alternative for high-performance lithium-ion *** addition,integrated with high thermal stability,the cellulose-based separator endows batteries with high safety at high temperatures,greatly expanding the application scenarios of energy storage devices in extreme environments.

关键词： lithium-ion batteries bio-inspired materials battery separators cellulose nanofiber ultrahigh ionic conductivity high safety