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光纤陀螺用光纤光源的新型自动温度控制

中国惯性技术学报 2010年第5期18卷 612-615页

作者：李绪友郝金会黄平王瑞哈尔滨工程大学自动化学院哈尔滨150001

光源良好的平均波长稳定性是保证光纤陀螺标度因子稳定性的重要条件。而光纤光源平均波长的变化主要源于环境温度的变化。为了使光源获得更好的输出特性,需要对光源泵浦温度进行精密控制。文中阐述了一种基于FPGA和MAX1968芯片设计的光... 详细信息

光源良好的平均波长稳定性是保证光纤陀螺标度因子稳定性的重要条件。而光纤光源平均波长的变化主要源于环境温度的变化。为了使光源获得更好的输出特性,需要对光源泵浦温度进行精密控制。文中阐述了一种基于FPGA和MAX1968芯片设计的光纤陀螺用光纤光源泵浦温度自动控制(ATC)技术。控制过程中提出了一种新的控制算法--递进式PID。与传统PID算法相比,递进式PID算法的最大特点是其各个参数可以随外界环境而变化。经试验测定,泵浦的温度稳定性能够稳定在±0.03℃以内,因而泵浦具有很好的平均波长稳定性。

关键词：光纤陀螺递进式PID 自动温度控制温度稳定性

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集成光学相位调制器相位漂移补偿方法研究

哈尔滨工程大学学报 2008年第1期29卷 45-49页

作者：陈世同孙枫李绪友哈尔滨工程大学自动化学院黑龙江哈尔滨150001

铌酸锂集成光学相位调制器是数字闭环光纤陀螺的核心器件.其半波电压随温度的变化和调制解调电路反馈通道增益的变化直接影响相位调制器调制特性,产生相位漂移,从而影响了标度因数的稳定性.为了补偿相位调制器的相位漂移,提高标度因数... 详细信息

铌酸锂集成光学相位调制器是数字闭环光纤陀螺的核心器件.其半波电压随温度的变化和调制解调电路反馈通道增益的变化直接影响相位调制器调制特性,产生相位漂移,从而影响了标度因数的稳定性.为了补偿相位调制器的相位漂移,提高标度因数的稳定性,提出引入了第2反馈回路的四状态偏置调制方法,给出了偏置调制方程,并分析了偏置相位的选择对系统信噪比的影响.对采用四状态调制的光纤陀螺进行测试,所得标度因数稳定性比单闭环方波调制方案提高了近一倍.结果证明,该方法对光纤陀螺标度因数稳定性的提高是有效的,具有重要意义.

关键词：集成光学相位调制器光纤陀螺四状态第2反馈回路

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

Perfluoropentane-based oxygen-loaded nanodroplets reduce microglial activation through metabolic reprogramming

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Neural Regeneration Research 2025年第4期20卷 1178-1191页

作者： Wanxian Luo Chuanhui xu linxi li Yunxiang Ji Yezhong Wang Yingjia li Yongyi Ye Department of Medicine Ultrasonics Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina Institute of Neuroscience Department of NeurosurgeryThe Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina

Microglia,the primary immune cells within the brain,have gained recognition as a promising therapeutic target for managing neurodegenerative diseases within the central nervous system,including Parkinson’s *** perfluorocarbon droplets have been reported to not only possess a high oxygen-carrying capacity,but also exhibit remarkable anti-inflammatory ***,the role of perfluoropentane in microglia-mediated central inflammatory reactions remains poorly *** this study,we developed perfluoropentane-based oxygen-loaded nanodroplets(PFP-OLNDs)and found that pretreatment with these droplets suppressed the lipopolysaccharide-induced activation of M1-type microglia in vitro and in vivo,and suppressed microglial activation in a mouse model of Parkinson’s *** suppression led to a reduction in the inflammatory response,oxidative stress,and cell migration capacity in ***,the neurotoxic effects were mitigated,which alleviated neuronal ***,ultrahigh-performance liquid chromatography–tandem mass spectrometry showed that the anti-inflammatory effects of PFP-OLNDs mainly resulted from the modulation of microglial metabolic *** further showed that PFP-OLNDs regulated microglial metabolic reprogramming through the AKT-mTOR-HIF-1α***,our findings suggest that the novel PFP-OLNDs constructed in this study alleviate microglia-mediated central inflammatory reactions through metabolic reprogramming.

关键词： metabolic reprogramming microglia microglial migration nanotherapy neurodegenerative diseases neuroinflammation oxygen-loaded nanodroplets Parkinson’s disease perfluoropentane ultra-performance liquid chromatography–mass spectrometry

Boosting Photocatalytic Performance of Cu-Mn Co-doped CeO_(2) Nanoparticles for Tetracycline Degradation

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 42-48页

作者： xu Rongqi MI Jianxin WANG Shulin xu Man ZHU li BAI Lei TANG Dandan LEI Yu Engineering Research Center of Environmental Materials and Membrane Technology of Hubei Province School of Materials Science and EngineeringWuhan Institute of TechnologyWuhan 430205China Shaanxi Coal Chemical Industry Technology Research Institute Co. Ltd.Xi’an 710100China

Cu-Mn co-doped CeO_(2) photocatalyst was successfully synthesized by the sol-gel method to assess its capability in degrading *** and TEM results showed that Cu and Mn were successfully co-doped into CeO_(2) without forming heterostructure,XPS and photoelectrochemical results revealed that Mn ions doping amplified the generation of photo-induced charge carriers,while Cu ions doping significantly facilitated the interfacial charge transfer ***,the optimized Cu3Mn2CeO_(2) nanoparticles exhibited the highest TC removal efficiency,achieved a rate of 78.18%and maintained a stable cycling performance.

关键词： photocatalyst co-doped charge separation water treatment

Morphological Mechanism and Experimental Verification of Self-healing of Basalt-fiber Modified Water-soaked Asphalt

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 171-186页

作者： XIAO Minmin DONG Jinyong li Chunyan GUO xu REN Jianguo School of Urban Construction and Safety Engineering Shanghai Institute of TechnologyShanghai 201418China

This study investigates the mechanism of action of representative molecules of basalt fibers on the healing of water-soaked *** parameters,morphological characteristics,interfacial healing energy,and interfacial healing strength were analyzed using molecular dynamics and macroscopic tests under different time,temperature,and water conditions to evaluate the specific states and critical conditions involved in *** results indicate that basalt-fiber molecules can induce rearrangement and a combination of water-soaked asphalt at the healing *** groups with different bonding states increase the interfacial adsorption capacity of water-soaked *** interaction between basalt fiber molecules and water molecules leads to a"hoop"phenomenon,while aromatics-2 molecules exhibit a"ring band aggregation"*** former reduces the miscibility of water and asphalt molecules,while the latter causes slow diffusion of the ***,a micro-macro dual-scale comparison of interfacial healing strength was conducted at temperatures of 297.15 and 312.15 K to identify the strength transition point and critical temperature of 299.4 K during the self-healing process of basalt-fiber modified water-soaked asphalt.

关键词： water-soaked asphalt basalt-fibers self-healing properties moisture status molecular characterization

Nb元素对粉末冶金TiAl基合金高温氧化行为的影响

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粉末冶金材料科学与工程 2015年第4期20卷 616-622页

作者：欧阳思慧刘彬李建波徐礼友刘咏中南大学粉末冶金国家重点实验室长沙410083

采用等离子旋转电极法制备Ti-47Al-2Cr-0.2Mo,Ti-50Al-2Nb-0.3W和Ti-45Al-7Nb-0.3W(元素含量均为原子分数,%)3种预合金粉末,再通过热等静压制备成块体合金,在950℃空气环境中进行合金的高温氧化实验,并利用扫描电镜(SEM)观察与分析合金... 详细信息

采用等离子旋转电极法制备Ti-47Al-2Cr-0.2Mo,Ti-50Al-2Nb-0.3W和Ti-45Al-7Nb-0.3W(元素含量均为原子分数,%)3种预合金粉末,再通过热等静压制备成块体合金,在950℃空气环境中进行合金的高温氧化实验,并利用扫描电镜(SEM)观察与分析合金氧化后的表面形貌以及截面的元素面分布,用X射线衍射(XRD)分析氧化膜的相组成,研究Nb元素及其含量对Ti Al基合金高温氧化行为的影响。结果表明:Nb元素的添加可提高粉末冶金Ti Al基合金的抗氧化性能,这3种合金中Ti-45Al-7Nb-0.3W合金的抗氧化性能最好,经过80 h氧化后质量增量仅为2.484 mg/cm2,为不含Nb合金的12.44%,并且氧化膜整体厚度最薄,最厚的地方氧化膜厚度约为8.3μm。该合金表面形成连续致密的Al2O3氧化层,氧化膜从外向内依次为TiO2层/Al2O3层/(Ti,Nb)O2层/富Al和Nb层。

关键词：粉末冶金 TiAl基合金高温氧化 Nb

基于ANSYS的拖拉机HMCVT太阳轮轴模态分析

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机械设计与制造 2012年第10期 231-233页

作者：徐立友李金辉河南科技大学车辆与动力工程学院洛阳471003

在介绍模态分析基本理论的基础上,基于UG软件建立了拖拉机液压机械无级变速器(HMCVT)太阳轮轴的三维模型,利用ANSYS-UG的数据接口将太阳轮轴三维实体模型导入ANSYS中生成有限元分析模型,并运用自由模态和约束模态两种分析方法对太阳轮... 详细信息

在介绍模态分析基本理论的基础上,基于UG软件建立了拖拉机液压机械无级变速器(HMCVT)太阳轮轴的三维模型,利用ANSYS-UG的数据接口将太阳轮轴三维实体模型导入ANSYS中生成有限元分析模型,并运用自由模态和约束模态两种分析方法对太阳轮轴进行了模态分析。结果表明:两种模态分析方法均可以得到较准确的计算分析结果,但约束模态分析方法更能反映系统的实际工作状况;太阳轮轴在低阶频率下以弯曲摸态为主,高阶频率下为整体的扭转模态以及整体和局部的混合模态。本研究对细长轴的结构设计及动态特性分析提供了理论依据。

关键词： ANSYS 太阳轮轴振动自由模态分析约束模态分析

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福州市城郊森林旅游服务质量评价研究

林业经济问题 2014年第5期34卷 453-458页

作者：李有绪陈秋华福建农林大学管理学院福州350002

通过文献综述、专家咨询等方法,确定城郊森林旅游服务质量评价指标体系;并运用于福州市国家森林公园实地调查。同时,采用模糊数学的综合评价方法对450个调查样本进行分析。结果显示:福州市城郊森林旅游服务质量水平处于"一般良好"的状态... 详细信息

通过文献综述、专家咨询等方法,确定城郊森林旅游服务质量评价指标体系;并运用于福州市国家森林公园实地调查。同时,采用模糊数学的综合评价方法对450个调查样本进行分析。结果显示:福州市城郊森林旅游服务质量水平处于"一般良好"的状态,福州市城郊森林旅游在其对游客的接待服务上、交通服务方面、游客游玩休憩服务这三者上存在缺陷。因此,提出提升服务质量、完善交通、增加特色项目、建立监测体系等若干具体建议。

关键词：城郊森林旅游服务质量评价模糊评价法