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基于定子磁链幅值和角度控制的异步电机直接转矩控制

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电气自动化 2009年第2期31卷 20-21,68页

作者：李春菊刘国荣彭磊湖南工程学院电气与信息工程系湖南湘潭411101 湘潭大学信息工程学院湖南湘潭411105

为减少异步电机转矩脉动和定子磁链固定偏差,提出了一种改进的异步电机直接转矩控制策略。该策略是基于给定定子磁链幅值和角度的解耦控制,用瞬时转差角频率和转子角频率之间的关系来调节定子磁链给定角,而给定定子磁链幅值保持额定值... 详细信息

为减少异步电机转矩脉动和定子磁链固定偏差,提出了一种改进的异步电机直接转矩控制策略。该策略是基于给定定子磁链幅值和角度的解耦控制,用瞬时转差角频率和转子角频率之间的关系来调节定子磁链给定角,而给定定子磁链幅值保持额定值不变。控制结构简单。通过Matlab6.5/simulink建立了仿真模型,仿真结果证实了该控制策略的有效性。

关键词：直接转矩控制定子磁链隔值和角度异步电机

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带钢拉弯矫直机机架结构的优化分析

冶金设备 2012年第2期 37-40页

作者：李春菊周存龙李伟娜太原科技大学山西太原030024

拉弯矫直机下机架现在常采用钢板焊接结构,组成下机架钢板的厚度、材质的差异,不仅对整体刚度影响较大,还直接影响到结构重量、产品成本。运用有限元方法对一种带钢拉弯矫直机的下机架在受载后的变形进行分析。以设备的总体刚度为目标值... 详细信息

拉弯矫直机下机架现在常采用钢板焊接结构,组成下机架钢板的厚度、材质的差异,不仅对整体刚度影响较大,还直接影响到结构重量、产品成本。运用有限元方法对一种带钢拉弯矫直机的下机架在受载后的变形进行分析。以设备的总体刚度为目标值,重量、安全系数等为约束函数,选择钢板的最佳厚度值,为拉弯矫直机的结构最优化设计提供了参考。

关键词：拉弯矫直机下机架有限元结构优化

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新形势下我国村镇规划工作探析

河北建筑工程学院学报 2007年第1期25卷 62-64页

作者：姜乖妮李春聚李孟波孙晓璐河北建筑工程学院建筑系

从村镇规划所指范围、现代村镇规划的概念、原则入手,分析在建设社会主义新农村这一新的历史阶段,我国村镇规划和村镇建设的现状,并提出相应的对策和建议.

关键词：村镇规划原则现状探析

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基于Inventor的拉弯矫直机虚拟制造

冶金设备 2013年第1期 7-10页

作者：孟岩李春菊周存龙中国山东对外经济技术合作集团有限公司山东济南250098 山东中川液压有限公司山东临沭276712 太原科技大学山西省冶金设备设计理论与技术重点实验室山西太原030024

为了避免拉弯矫直机在研发过程中存在的生产周期长、成本高、产品质量低等缺点,采用Inventor软件对拉弯矫直机进行虚拟制造及关键部件的应力分析。首先建立拉弯矫直机的三维实体模型和虚拟装配,其次对设备中的关键部件进行受力分析,从... 详细信息

为了避免拉弯矫直机在研发过程中存在的生产周期长、成本高、产品质量低等缺点,采用Inventor软件对拉弯矫直机进行虚拟制造及关键部件的应力分析。首先建立拉弯矫直机的三维实体模型和虚拟装配,其次对设备中的关键部件进行受力分析,从而可方便、迅速地检查和评价产品的设计方案,确保了产品设计尺寸的准确性。

关键词：拉弯矫直机 Inventor软件虚拟制造应力分析

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He li li Sai Wang Shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

Climate change response to astronomical forcing during the Oligocene-Miocene transition in the equatorial Atlantic(ODP Site 926)

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Science China Earth Sciences 2016年第8期59卷 1665-1673页

作者： ZOU ZhuoYan HUANG chunju li MingSong ZHANG Yang State Key Laboratory of Biogeology and Environmental Geology School of Earth Sciences China University of Geosciences Department of Earth and Planetary Sciences Johns Hopkins University Department of Earth Atmospheric and Planetary Sciences Purdue University

The Oligocene-Miocene transition period was characterized by a decrease in global CO2 levels, expansion of polar ice sheet, fall in global sea-level, etc. However, the reasons for, and mechanisms of, this global, extreme-cold climate change event（Mi-1） still remain controversial. Our samples from the core of the Ocean Drilling Program（ODP） Leg 154, Site 926, located in the equatorial Atlantic, mainly consist of light-gray, nannofossil chalk with foraminifers interbedded with greenish-gray, clayey, nannofossil chalk sediments. Color variation from light-gray layers（up to 80% carbonate content） to dark layers（60% carbonate content） was observed to occur cyclically at the meter scale. Therefore, we chose color reflectance lightness（L*） data as the paleoclimate proxy on which to perform cyclostratigraphic analysis because it could reflect carbonate content changes. Based on the recognition of the 405 kyr long eccentricity and 40 kyr obliquity cycles of the L* series, we tuned the series to establish an absolute astronomical time scale using the published age of the Oligocene-Miocene boundary（OMB） as the anchor for an absolute age control point. The power spectra of the tuned L* series showed that the long eccentricity signals became significantly weak, while the obliquity signals became strong, from the Late Oligocene to the Early Miocene. The 405 kyr long eccentricity minimum coincided with the 1.2 Myr obliquity node at the OMB, and similar convergences might be closely related to other extreme-cold events in Earth’s history. In addition, the sedimentation accumulation rate, oxygen isotopes of benthonic foraminifers, and rodents’ per-taxon turnover rate from Central Spain showed the same 2 Myr cyclicity, which indicates the significant influence of Earth-orbital forcing on the Earth system and ecological evolution on the million-year time scale.

关键词： Late Oligocene-Early Miocene ODP Site 926 lightness Astronomical time scale Astronomical forcing

Cell polarization in ischemic stroke: molecular mechanisms and advances

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Neural Regeneration Research 2025年第3期20卷 632-645页

作者： Yuanwei li Xiaoxiao Xu Xuan Wu Jiarui li Shiling Chen Danyang Chen Gaigai li Zhouping Tang Department of Neurology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Ischemic stroke is a cerebrovascular disease associated with high mortality and disability rates. Since the inflammation and immune response play a central role in driving ischemic damage, it becomes essential to modulate excessive inflammatory reactions to promote cell survival and facilitate tissue repair around the injury site. Various cell types are involved in the inflammatory response, including microglia, astrocytes, and neutrophils, each exhibiting distinct phenotypic profiles upon stimulation. They display either proinflammatory or anti-inflammatory states, a phenomenon known as ‘cell polarization.’ There are two cell polarization therapy strategies. The first involves inducing cells into a neuroprotective phenotype in vitro, then reintroducing them autologously. The second approach utilizes small molecular substances to directly affect cells in vivo. In this review, we elucidate the polarization dynamics of the three reactive cell populations(microglia, astrocytes, and neutrophils) in the context of ischemic stroke, and provide a comprehensive summary of the molecular mechanisms involved in their phenotypic switching. By unraveling the complexity of cell polarization, we hope to offer insights for future research on neuroinflammation and novel therapeutic strategies for ischemic stroke.

关键词： astrocyte polarization immune regulation inflammation ischemic injury microglia polarization neutrophil polarization signaling pathways stroke

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我国10个省区绞股蓝的皂甙含量分析

热带作物学报 2008年第6期29卷 814-817页

作者：张涛张育松张顺萍赖翠霞李春菊袁弟顺福建农林大学农产品品质研究所福建农林大学科技开发总公司福州350002 福建农林大学中国白茶研究所

用超声提取法提取,比色法测定,对10个省区绞股蓝的皂甙含量进行比较分析。结果表明,绞股蓝根部皂甙最高含量为7.75%,最低为0.68%;茎部皂甙最高含量为4.65%,最低为1.02%;叶部皂甙最高含量为6.86%,最低为2.03%。省区和绞股蓝皂甙含量之间... 详细信息

用超声提取法提取,比色法测定,对10个省区绞股蓝的皂甙含量进行比较分析。结果表明,绞股蓝根部皂甙最高含量为7.75%,最低为0.68%;茎部皂甙最高含量为4.65%,最低为1.02%;叶部皂甙最高含量为6.86%,最低为2.03%。省区和绞股蓝皂甙含量之间没有相关性,地区差异导致的环境因子多样性是皂甙含量差异的主要原因。

关键词：绞股蓝皂甙含量分析

Design of a cationic accelerator enabling ultrafast ion diffusion kinetics in aqueous zinc-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 377-384页

作者： Yawei Xiao Qianqian Gu Haoyu li Mengyao li Yude Wang National Center for International Research on Photoelectric and Energy Materials School of Materials and Energy Yunnan University Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island Resources School of Chemistry and Chemical Engineering Hainan University College of Chemical Engineering Fuzhou University Yunnan Key Laboratory of Carbon Neutrality and Green Low-carbon Technologies Yunnan University

Aqueous zinc-ion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion *** address this,a strategy has been developed to create a cation-accelerating electric field on the surface of the cathode to achieve ultrafast Zn2+diffusion *** employing electrodeposition to coat MoS2on the surface of BaV6O16·3H2O nanowires,the directional built-in electric field generated at the heterointerface acts as a cation accelerator,continuously accelerating Zn2+diffusion into the active *** optimized Zn2+diffusion coefficient in CC@BaV-6O16·3H2O@MoS2(7.5×10～8cm2s-1) surpasses that of most reported V-based ***,MoS2serving as a cathodic armor extends the cycling life of the Zn-CC@BaV6O16·3H2O@MoS2full batteries to over 10000 *** work provides valuable insights into optimizing ion diffusion kinetics for high-performance energy storage devices.

关键词： Internal electric field Cationic accelerator Ion diffusion kinetics Cathode modification strategy Aqueous zinc ion battery