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H13及其改进热作模具钢热力学动力学计算

一重技术 2022年第3期 22-27,5,72页

作者：张雪姣张心金李晗肖志霞朱琳天津重型装备工程研究有限公司天津300457 河北工业大学材料科学与工程学院天津300130

针对热作模具钢H13及其三种改进钢种进行材料热力学、动力学计算,分析H13钢的基本平衡相及碳化物析出动力学,研究三种改进型钢种的成分设计思路,讨论各改进型热作模具稳定性相较H13钢有极大提高的原因。结果表明:提高M C(,N)、M6C的析出... 详细信息

针对热作模具钢H13及其三种改进钢种进行材料热力学、动力学计算,分析H13钢的基本平衡相及碳化物析出动力学,研究三种改进型钢种的成分设计思路,讨论各改进型热作模具稳定性相较H13钢有极大提高的原因。结果表明:提高M C(,N)、M6C的析出量,延长析出时间,降低长大速度均可提高H13钢的热稳定性。

关键词： H13 热作模具钢材料计算平衡相图碳化物

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含Nb高速钢轧辊的淬火工艺研究

热加工工艺 2021年第6期50卷 150-153,157页

作者：苏铭肖志霞冯建航陈兴富刘杰兵袁乃博殷福星河北工业大学材料科学与工程学院天津300130 河北工业大学能源装备材料技术研究院天津300130 河北省轧辊绿色制造技术创新中心河北邢台054000 邢台德龙机械轧辊有限公司河北邢台054000

通过比较分析了含Nb高速钢离心铸造轧辊不同温度淬火后的碳化物、残余奥氏体及硬度变化规律,获得最佳的淬火热处理工艺。结果表明:随着淬火温度的升高,晶粒度降低,且在淬火温度超过1100℃时,晶粒度下降明显。随着淬火温度的升高,碳化物... 详细信息

通过比较分析了含Nb高速钢离心铸造轧辊不同温度淬火后的碳化物、残余奥氏体及硬度变化规律,获得最佳的淬火热处理工艺。结果表明:随着淬火温度的升高,晶粒度降低,且在淬火温度超过1100℃时,晶粒度下降明显。随着淬火温度的升高,碳化物不断溶解,当淬火温度升至1150℃时,碳化物量含量最低,降至5.7%,残余奥氏体量增加至37.6%。硬度随着淬火温度的升高先上升后下降,当淬火温度为1050℃时,硬度最高,为63.6 HRC。热处理后的碳化物类型主要为颗粒状的MC和片层状M2C。综合比较,淬火温度控制在1050℃为宜。

关键词：高速钢轧辊热处理 Nb 碳化物

An electromagnetic semi-active dynamic vibration absorber for thin-walled workpiece vibration suppression in mirror milling

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1315-1334页

作者： Jianghua KONG Bei DING Wei WANG zhixia WANG Juliang xiao Hongyun QIU School of Mechanical Engineering Tianjin UniversityTianjin 300350China Tianjin Key Laboratory of Nonlinear Dynamics and Control Tianjin 300350China Key Laboratory of Modern Mechanisms and Equipment Design of the State Ministry of Education Tianjin UniversityTianjin 300350China

As critical components of aircraft skins and rocket fuel storage tank shells,large thin-walled workpieces are susceptible to vibration and deformation during machining due to their weak local *** address these challenges,we propose a novel tunable electromagnetic semi-active dynamic vibration absorber(ESADVA),which integrates with a magnetic suction follower to form a followed ESADVA(follow-ESADVA)for mirror *** system combines a tunable magnet oscillator with a follower,enabling real-time vibration absorption and condition feedback throughout the milling ***,the device supports self-sensing and frequency adjustment by providing feedback to a linear actuator,which alters the distance between *** resolves the traditional issue of being unable to directly monitor vibration at the machining point due to space constraints and tool *** frequency shift characteristics and vibration absorption performance are comprehensively *** and experimental results demonstrate that the prototyped follow-ESADVA achieves frequency synchronization with the milling tool,resulting in a vibration suppression rate of approximately 47.57%.Moreover,the roughness of the machined surface decreases by18.95%,significantly enhancing the surface *** results of this work pave the way for higher-quality machined surfaces and a more stable mirror milling process.

关键词： semi-active dynamic vibration absorber(SADVA) mirror milling selfsensing vibration absorption tuning thin-walled workpiece

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板状铸钢件冒口补缩距离的模拟计算

一重技术 2013年第6期 62-65页

作者：吉晓霞肖志霞郭建政赵晓光赵亚楠中国第一重型机械股份公司能源装备材料科学研究所工程师天津300457

采用铸造模拟软件ProCAST研究冒口直径,冒口高度以及板厚等对板状铸钢件有效补缩距离的影响。研究表明,板状铸钢件冒口补缩规律与传统冒口有所不同。板状铸钢件末端区与冒口直径和冒口高度无关,与板厚有关,随板厚增大而增大,且增大趋势... 详细信息

采用铸造模拟软件ProCAST研究冒口直径,冒口高度以及板厚等对板状铸钢件有效补缩距离的影响。研究表明,板状铸钢件冒口补缩规律与传统冒口有所不同。板状铸钢件末端区与冒口直径和冒口高度无关,与板厚有关,随板厚增大而增大,且增大趋势变大,与板厚成非线性关系;板状铸钢件冒口区随板厚、冒口直径以及冒口高度的增大而增大,但增大趋势变缓;板状铸钢件冒口区随冒口模数的增大而增大,当冒口模数小于铸件模数时,增大较明显,当冒口模数大于铸件模数时,增大趋势逐渐变缓。

关键词：板状铸钢件冒口区末端区冒口直径冒口高度板厚

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高锰钢前导轮铸造工艺模拟及优化

一重技术 2013年第6期 58-61页

作者：肖志霞郭建政董治中陈席国李萌蘖中国第一重型机械股份公司能源装备材料科学研究所工程师天津300457

高锰钢前导轮内腔结构复杂,需要合理的铸造工艺以避免其内部产生铸造缺陷。为此,采用商业软件ProCAST对导轮轴孔处设一个明冒口的单冒口工艺(SR)和两个明冒口的双冒口工艺(DR)进行缺陷预测。计算发现,单冒口工艺(SR)的缺陷形成倾向低于... 详细信息

高锰钢前导轮内腔结构复杂,需要合理的铸造工艺以避免其内部产生铸造缺陷。为此,采用商业软件ProCAST对导轮轴孔处设一个明冒口的单冒口工艺(SR)和两个明冒口的双冒口工艺(DR)进行缺陷预测。计算发现,单冒口工艺(SR)的缺陷形成倾向低于双冒口的工艺(DR)。进而,通过调整单冒口工艺(SR)的冷铁形状、位置及增大轮缘处暗冒口体积,提出优化工艺M1;在M1基础上,通过减小轴孔处明冒口体积,并加大该处冒口保温砖厚度,提出优化工艺M2。模拟计算表明,采用M1和M2工艺均可消除导轮轮缘处的缩孔缩松缺陷;以M2的热裂倾向最小,热裂纹主要出现在前导轮内腔垂直拐角处和轴孔附近。

关键词：高锰钢前导轮热裂 ProCAST 模拟计算

Identification of a novel salt tolerance gene in wild soybean by whole-genome sequencing

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Identification of a novel salt tolerance gene in wild soybea...

第十四届全国中药和天然药物学术研讨会

作者： Xinpeng Qi Man-Wah Li Min Xie Xin Liu Meng Ni Guihua Shao Chi Song Aldrin Kay-Yuen Yim Ye Tao Fuk-Ling Wong Sachiko Isobe Chi-Fai Wong Kwong-Sen Wong Chunyan Xu Chunqing Li Ying Wang Rui Guan Fengming Sun Guangyi Fan zhixia xiao Feng Zhou Tsui-Hung Phang Xuan Liu Suk-Wah Tong Ting-Fung Chan Siu-Ming Yiu Satoshi Tabata Jian Wang Xun Xu Hon-Ming Lam School of Life Sciences and Center for Soybean Research of the State Key Laboratory of Agrobiotechnology The Chinese University of Hong Kong BGI-Shenzhen Institute of Crop Sciences The Chinese Academy of Agricultural Sciences Kazusa DNA Research Institute Department of Computer Science The University of Hong Kong

＜正＞Using a whole-genome-sequencing approach to explore germplasm resources can serve as an important strategy for crop improvement,especially in investigating wild accessions that may contain useful genetic resources that have been lost during the domestication *** we sequence and assemble a draft genome of wild soybean and construct a

关键词：

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基于创客教育2．0的护理学混合式教学研究

中国实用护理杂志 2017年第5期33卷 384-387页

作者：杨凯涵江智霞陈美肖烨陈格钟明利罗公印遵义医学院护理学院 563003 遵义医学院附属医院急诊科遵义医学院附属医院ICU

目的分析创客教育2.0产生的背景、内涵,以及将其引入到护理教育中的创新性;提出基于创客教育2.0的护理学混合式教学.方法采用文献研究法、描述性研究法对创客教育2.0的应用现状及与护理教育的联系进行分析,根据分析结果采用探索性研... 详细信息

目的分析创客教育2.0产生的背景、内涵,以及将其引入到护理教育中的创新性;提出基于创客教育2.0的护理学混合式教学.方法采用文献研究法、描述性研究法对创客教育2.0的应用现状及与护理教育的联系进行分析,根据分析结果采用探索性研究法设计基于创客教育2.0的护理学混合式教学框架.结果虽然创客教育2.0已逐渐成为培养学生创新能力的重要途径,各级各类学校在尝试实施创客教育2.0,然而在护理教育领域中,目前尚未出现相关研究报道.结论探索基于创客教育2.0的护理学混合式教学可在一定程度上促进护理教育的改革;为了更加深入地探讨创客教育2.0在护理教育中的应用效果,还需针对其发展机制、支持理论等方面展开研究.

关键词：创客教育2.0 创客护理教育混合式教学

Multi-Dimensional Composite Frame as Bifunctional Catalytic Medium for Ultra-Fast Charging Lithium-Sulfur Battery

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Nano-Micro Letters 2022年第12期14卷 91-105页

作者： Shuhao Tian Qi Zeng Guo Liu Juanjuan Huang xiao Sun Di Wang Hongcen Yang Zhe Liu Xichao Mo zhixia Wang Kun Tao Shanglong Peng National and Local Joint Engineering Laboratory for Optical Conversion Materials and Technology School of Materials and EnergyLanzhou UniversityLanzhou 730000People’s Republic of China School of Physical Science and Technology Lanzhou UniversityLanzhou 730000People’s Republic of China

The shuttle effect of soluble lithium polysulfides(LiPSs)between electrodes and slow reaction kinetics lead to extreme inefficiency and poor high current cycling stability,which limits the commercial application of Li-S ***,the multi-dimensional composite frame has been proposed as the modified separator(MCCoS/PP)of Li-S battery,which is composed of CoS_(2) nanoparticles on alkali-treated MXene nanosheets and carbon *** experiments and theoretical calculations show that bifunctional catalytic activity can be achieved on the MCCoS/PP *** can not only promote the liquid-solid conversion in the reduction process,but also accelerate the decomposition of insoluble Li_(2)S in the oxidation *** addition,LiPSs shuttle effect has been inhibited without a decrease in lithium-ion transference ***,the MCCoS/PP separator with good LiPSs adsorption capability arouses redistribution and fixing of active substances,which is also beneficial to the rate performance and cycling *** Li-S batteries with the MCCoS/PP separator have a specific capacity of 368.6 mAh g^(−1) at 20C,and the capacity decay per cycle is only 0.033%in 1000 cycles at ***,high area capacity(6.34 mAh cm^(−2))with a high sulfur loading(7.7 mg cm^(−2))and a low electrolyte/sulfur ratio(7.5μL mg^(−1))is achieved.

关键词： MXenes Transition metal sulfides Lithium-ion transference Bifunctional catalysis Reaction kinetics

Emodin alleviates cardiac fibrosis by suppressing activation of cardiac fibroblasts via upregulating metastasis associated protein 3

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Acta Pharmaceutica Sinica B 2019年第4期9卷 724-733页

作者： Dan xiao Yue Zhang Rui Wang Yujie Fu Tong Zhou Hongtao Diao zhixia Wang Yuan Lin Zhange Li Lin Wen Xujuan Kang Philipp Kopylov Dmitri Shchekochikhin Yong Zhang Baofeng Yang Department of Pharmacology(State-Province Key Laboratories of Biomedicine-Pharmaceutics of China Key Laboratory of Cardiovascular ResearchMinistry of Education)Harbin Medical UniversityHarbin 150081China Department of Pharmacy The First Affiliated Hospital of Harbin Medical UniversityHarbin 150081China Department of Preventive and Emergency Cardiology Sechenov First Moscow State Medical UniversityMoscow 119991Russian Federation Institute of Metabolic Disease Heilongjiang Academy of Medical ScienceHarbin 150086China Department of Pharmacology and Therapeutics Melbourne School of Biomedical SciencesFaculty of MedicineDentistry and Health SciencesThe University of MelbourneMelbourne 3010Australia

Excess activation of cardiac fibroblasts inevitably induces cardiac fibrosis. Emodin has been used as a natural medicine against several chronic diseases. The objective of this study is to determine the effects of emodin on cardiac fibrosis and the underlying molecular mechanisms. Intragastric administration of emodin markedly decreased left ventricular wall thickness in a mouse model of pathological cardiac hypertrophy with excess fibrosis induced by transaortic constriction(TAC) and suppressed activation of cardiac fibroblasts induced by angiotensin II(AngII). Emodin upregulated expression of metastasis associated protein 3(MTA3) and restored the MTA3 expression in the setting of cardiac fibrosis. Moreover, overexpression of MTA3 promoted cardiac fibrosis;in contrast, silence of MTA3 abrogated the inhibitory effect of emodin on fibroblast activation. Our findings unraveled the potential of emodin to alleviate cardiac fibrosis via upregulating MTA3 and highlight the regulatory role of MTA3 in the development of cardiac fibrosis.

关键词： Emodin Cardiac fibrosis MTA3 Angiotensin Ⅱ Cardiac fibroblast Mouse