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Modeling and analysis of cantilever beam with active-passive hybrid piezoelectric network

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Science China(Technological Sciences) 2013年第9期56卷 2326-2335页

作者： li mingming FANG Bo CAO DengQing HUANG WenHu School of Astronautics Harbin Institute of Technology

The active-passive hybrid piezoelectric network (APPN) is investigated to reduce the vibration of cantilever beam. Hamilton's principle with the Rayleigh-Ritz method is used to derive the equations of motion of the beam with the APPN. Only one piezoelectric actuator is bonded on the cantilever beam, so in the segment of the beam where the piezoelectric actuator is attached, the neutral axis is not the geometric center of the beam. This change on the neutral axis is considered in the process of deriving equations. Selecting RL circuit as passive shunt circuit, open-loop analysis is performed to gain insight into the passive damping features. Velocity feedback control is then employed to analyze the characteristics of the closed-loop system. Numerical results show that the APPN has a significant effect on vibration suppression, especially at narrow frequency bands. On this basis, variable RL circuit is proposed and analyzed for broadband vibration attenuation. Numerical simulations illustrate that this scheme is effective and feasible.

关键词： active-passive hybrid piezoelectric network active control passive shunt damping Hamilton's principle

One-pot Synthesis of Aromatic Fused 2,3-Dihydroindanone by Tandem Pauson-Khand/Michael/Henry Reaction

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Chinese Journal of Chemistry 2013年第1期31卷 49-54页

作者： mingming li Ping Xing Zuogang Huang Biao Jiang CAS Key Laboratory of Synthetic Chemistry of Natural Substances Shanghai Institute of Organic Chemistry Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 China Shanghai Advanced Research Institute Chinese Academy of Sciences 99 Haike Road Shanghai 201210 China

The intermolecular Pauson-Khand reaction between 2-ethynylbenzaldehyde and ethylene promoted by dimethyl sulfide can be utilized to synthesize 2-（2-formylphenyl）cyclopentenone efficiently. This compound and its deriva- tives undergo a cascade process of Michael addition reaction followed by Henry reaction with nitromethane to con- struct substituted aromatic fused 2,3-dihydroindanones. Furthermore, direct one-pot synthesis of aromatic fused 2,3-dihydroindanones from 2-ethynylbenzaldehyde is achieved.

关键词： 2-ethynylbenzaldehyde tandem Pauson-Khand/Michael/Henry reaction aromatic fused 2,3-dihydro-indanone

Sm^(3+)掺杂Na_(5)Y(MoO_(4))_(4-y)(WO_(4))_(y)高热稳定性荧光粉的制备及发光性能研究

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人工晶体学报 2024年第6期53卷 1016-1025页

作者：胡正开杨伟斌熊飞兵郭益升白鑫李明明厦门理工学院光电与通信工程学院厦门361024 厦门理工学院福建省光电技术与器件重点实验室厦门361024

本文采用高温固相法合成了一系列Na_(5)Y_(1-x)(MoO_(4))_(4-y)(WO_(4))y∶xSm^(3+)(x=0~0.10,y=0~4)橙红色荧光粉。通过粉末衍射、透射电镜、常温/变温荧光发射谱、荧光激发谱、荧光动态衰减曲线和CIE色度坐标等光谱手段对荧光粉样品... 详细信息

本文采用高温固相法合成了一系列Na_(5)Y_(1-x)(MoO_(4))_(4-y)(WO_(4))y∶xSm^(3+)(x=0~0.10,y=0~4)橙红色荧光粉。通过粉末衍射、透射电镜、常温/变温荧光发射谱、荧光激发谱、荧光动态衰减曲线和CIE色度坐标等光谱手段对荧光粉样品的光谱性能进行了研究。粉末衍射结果表明,合成的样品相位与Na_(5)Y(MoO_(4))_(4)的标准相一致,Sm^(3+)掺杂与引入(WO_(4))2-均未改变材料的相结构。在波长为406 nm光源的激发下,Na_(5)Y0.92(MoO_(4))3WO_(4)∶0.08Sm^(3+)荧光粉在643 nm附近橙红色荧光发射强度最高,继续增加Sm^(3+)的掺杂浓度,存在荧光猝灭现象,浓度猝灭的主要原因归为电偶极-电偶极相互作用。研究发现,Na_(5)Y(MoO_(4))_(4)基质中掺杂Sm^(3+)会引起电负性改变和晶格畸变,在Na_(5)Y_(1-x)(MoO_(4))_(4)∶xSm^(3+)中引入(WO_(4))2-阴离子基团,可以弥补因掺杂Sm^(3+)出现的缺陷,改善Na_(5)Y(MoO_(4))_(4)∶xSm^(3+)荧光粉的发光性能。在300~440 K,样品具有优异的热稳定性,荧光发射强度均超过室温时的96%;其CIE色度坐标均位于橙红光区域。以上结果表明新型Na_(5)Y_(1-x)(MoO_(4))_(4-y)(WO_(4))y∶xSm^(3+)橙红色荧光粉在WLED应用上有潜在价值。

关键词： Na_(5)Y(MoO_(4))_(4) 荧光粉 Sm^(3+)掺杂高温固相法荧光发射强度热稳定性白光LED

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羊肉品质重要候选基因研究进展

家畜生态学报 2024年第6期45卷 1-8页

作者：贺娜孙睿哲邓玉婷李明明张军霞青海大学农牧学院青海西宁810000

羊肉凭借高蛋白、低胆固醇、低脂肪等特点受到消费者的喜爱。现阶段,育种学家们通过分子生物学的方式筛选与羊肉品质相关的候选基因,为肉羊品种改良等分子育种提供依据,以促进羊肉品质的提升。该文就与羊肉pH、肌内脂肪沉积以及脂肪酸... 详细信息

羊肉凭借高蛋白、低胆固醇、低脂肪等特点受到消费者的喜爱。现阶段,育种学家们通过分子生物学的方式筛选与羊肉品质相关的候选基因,为肉羊品种改良等分子育种提供依据,以促进羊肉品质的提升。该文就与羊肉pH、肌内脂肪沉积以及脂肪酸分布等相关的候选基因进行综述,以期为后续羊的遗传改良、羊肉品质提高以及新育种技术的研发提供参考。

关键词：羊肉候选基因肉品质

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本钢特钢中棒材头部弯曲改善

冶金信息导刊 2024年第5期61卷 27-30页

作者：王东李明明于海啸本钢板材股份有限公司本溪117000

分析本钢特钢中棒材头部弯曲产生的原因,通过优化加热工艺、新增定径轧制工艺、改进出入口导卫固定方式与出口导卫内堂尺寸,有效降低了中棒材头部弯曲度及弯曲比例,显著提升钢材外观质量,减少金属损失,降低了生产成本。

关键词：头部弯曲加热轧机导卫定径轧制

A case study of a Kuroshio main path cut-off event and impacts on the South China Sea in fall-winter 2013–2014

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Acta Oceanologica Sinica 2019年第4期38卷 12-19页

作者： Quanan Zheng Chung-Ru Ho lingling Xie mingming li Department of Atmospheric and Oceanic Science University of Maryland Guangdong Key Laboratory of Coastal Ocean Variability and Disaster Prediction Guangdong Ocean University Department of Marine Environmental Informatics National Taiwan Ocean University

This study examines a Kuroshio main path(KMP) cut-off event east of Taiwan Island occurred in fall-winter2013–2014 and its impacts on the South China Sea(SCS) by analyzing satellite altimetry and mooring observations. Satellite altimeter sea level anomaly(SLA) images reveal a complete process that a huge cyclonic eddy(CE) from the Pacific collided with the Kuroshio and the western boundary from 15 October 2013 to 15 January 2014. Mooring observations evidenced that the Kuroshio upper ocean volume transport was cut off more than 82% from 17×106 m^3/s in September to 3×106 m^3/s in November 2013. The KMP cut-off event caused the Kuroshio branching and intruding into the SCS and strengthened the eddy kinetic energy in the northern SCS west of the Luzon Strait. Using the total momentum as a dynamic criterion to determine the role of eddy collision with the Kuroshio reasonably explains the KMP cut-off event.

关键词： KMP cut-off event eddy kinetic energy dynamic criterion South China Sea

Interleukin-1β is a potential therapeutic target for periodontitis: a narrative review

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International Journal of Oral Science 2020年第1期12卷 1-9页

作者： Ran Cheng Zhiwu Wu mingming li Meiying Shao Tao Hu State Key Laboratory of Oral Diseases&National Clinical Research Center for Oral Diseases&West China Hospital of Stomatology Sichuan UniversityChengduChina West China School of Public Health and West China Fourth Hospital Sichuan UniversityChengduChina

Interleukin(IL)-1β, a pro-inflammatory cytokine, was elevated and participates in periodontitis. Not only the link between IL-1β and periodontitis was proved by clinical evidence, but also the increased IL-1β triggers a series of inflammatory reactions and promotes bone resorption. Currently, IL-1β blockage has been therapeutic strategies for autoimmune and autoinflammatory diseases such as rheumatoid arthritis, cryopyrin-associated periodic syndromes, gout and type II diabetes mellitus. It is speculated that IL-1β be a potential therapeutic target for periodontitis. The review focuses on the production, mechanism, present treatments and future potential strategies for IL-1β in periodontitis.

关键词： Interleukin therapeutic period

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代谢组学在肺癌治疗生物标志物中的研究进展

中国医院药学杂志 2024年第3期44卷 356-359页

作者：邓易汤浩李明明张凤陈万生上海市松江区中心医院药剂科上海310000 海军军医大学第二附属医院药剂科上海200003 上海中医药大学中药研究所上海201203

肺癌具有死亡率高、预后差、5年生存率低的特点,目前以化疗为主的综合治疗方案是非小细胞肺癌(non-small cell lung cancer,NSCLC)的主要治疗方式。根据肺癌的分期分型,患者相应接受包括手术、放疗、化疗以及靶向的综合治疗,然而早期症... 详细信息

肺癌具有死亡率高、预后差、5年生存率低的特点,目前以化疗为主的综合治疗方案是非小细胞肺癌(non-small cell lung cancer,NSCLC)的主要治疗方式。根据肺癌的分期分型,患者相应接受包括手术、放疗、化疗以及靶向的综合治疗,然而早期症状不显著、个体化差异巨大、放疗抵抗和化疗耐药等问题限制了患者的诊断和治疗效果,从而严重影响患者的身体健康。代谢组学从小分子代谢物的角度为发掘肿瘤生物标志物、评估整体代谢变化、研究发病机制提供着越来越重要的作用。该文主要综述了基于代谢组学技术的肺癌治疗预后效果评价生物标志物的研究进展,以期为肺癌个体化精准治疗提供重要理论依据,帮助临床患者取得治疗收益的最大化。

关键词：代谢组学生物标志物肺癌预后效果

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本钢特钢小棒材表面划伤改善

冶金信息导刊 2024年第3期61卷 31-33页

作者：王东李明明于海啸本钢板材股份有限公司特殊钢事业部本溪117000 本钢技术中心本溪117000

分析本钢特钢小棒材表面划伤产生的原因,通过对轧机工装精度提升的管控,空过辊道两侧加装惰轮,设计制作裙板耐磨锥轮,有效解决小棒材表面划伤问题,显著提升成品表面质量,缩短交货期,降低生产成本。

关键词：小棒划伤工装辊道裙板冷床