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Dy^(3+)激活的liSrBO_3材料光谱特性研究

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光谱学与光谱分析 2010年第1期30卷 18-21页

作者：王志军李盼来庞立斌杨志平郭庆林傅广生李旭河北大学物理科学与技术学院河北保定071002 河北大学大学外语教学部河北保定071002

研究了Dy^(3+)激活的liSrBO_3材料的光谱特性。材料的发射光谱为一多峰宽谱,主峰分别为486,578和668 nm;监测578 nm发射峰时所得材料的激发光谱为一多峰宽谱,主峰分别为331,368,397,433,462和478 nm。研究了Dy^(3+)掺杂浓度对材料发射... 详细信息

研究了Dy^(3+)激活的liSrBO_3材料的光谱特性。材料的发射光谱为一多峰宽谱,主峰分别为486,578和668 nm;监测578 nm发射峰时所得材料的激发光谱为一多峰宽谱,主峰分别为331,368,397,433,462和478 nm。研究了Dy^(3+)掺杂浓度对材料发射光谱的影响,结果显示,随Dy^(3+)浓度的增大,黄、蓝发射峰强度比(Y/B)逐渐增大;同时材料的发光强度随Dy^(3+)浓度的增大呈现先增大后减小的趋势,在Dy^(3+)浓度为3 mol%时到达峰值,其浓度猝灭机理为电偶极·偶极相互作用。引入li^+,Na^+和K^+均可提高材料的发射强度。

关键词： Dy^3+ liSrBO_3 光谱特性

Cholesterol metabolism: physiological versus pathological aspects in intracerebral hemorrhage

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Neural Regeneration Research 2025年第4期20卷 1015-1030页

作者： Ruoyu Huang Qiuyu pang Lexin Zheng Jiaxi lin Hanxi li lingbo Wan Tao Wang Department of Forensic Science School of Basic Medicine and Biological SciencesSuzhou Medicine College of Soochow UniversitySuzhouJiangsu ProvinceChina

Cholesterol is an important component of plasma membranes and participates in many basic life functions,such as the maintenance of cell membrane stability,the synthesis of steroid hormones,and *** plays a key role in the establishment and maintenance of the central nervous *** brain contains 20%of the whole body’s cholesterol,80%of which is located within myelin.A huge number of processes(e.g.,the sterol regulatory element-binding protein pathway and liver X receptor pathway)participate in the regulation of cholesterol metabolism in the brain via mechanisms that include cholesterol biosynthesis,intracellular transport,and *** brain injuries or diseases involving crosstalk among the processes above can affect normal cholesterol metabolism to induce detrimental ***,we hypothesized that cholesterol-related molecules and pathways can serve as therapeutic targets for central nervous system *** hemorrhage is the most severe hemorrhagic stroke subtype,with high mortality and *** cholesterol levels are associated with the risk of intracerebral ***,secondary pathological changes after intracerebral hemorrhage are associated with cholesterol metabolism dysregulation,such as neuroinflammation,demyelination,and multiple types of programmed cell *** cholesterol accumulation in the brain has been found after intracerebral *** this paper,we review normal cholesterol metabolism in the central nervous system,the mechanisms known to participate in the disturbance of cholesterol metabolism after intracerebral hemorrhage,and the links between cholesterol metabolism and cell *** also review several possible and constructive therapeutic targets identified based on cholesterol metabolism to provide cholesterol-based perspectives and a reference for those interested in the treatment of intracerebral hemorrhage.

关键词： cell death cholesterol metabolism intracerebral hemorrhage myelination therapeutic target

Gut microbiota-astrocyte axis: new insights into age-related cognitive decline

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Neural Regeneration Research 2025年第4期20卷 990-1008页

作者： Lan Zhang Jingge Wei Xilei liu Dai li Xiaoqi pang Fanglian Chen Hailong Cao Ping Lei Haihe Laboratory of Cell Ecosystem Department of GeriatricsTianjin Medical University General HospitalTianjinChina Tianjin Geriatrics Institute Tianjin Medical University General HospitalTianjinChina Department of Gastroenterology and Hepatology Tianjin Medical University General HospitalNational Key Clinical SpecialtyTianjin Institute of Digestive DiseasesTianjin Key Laboratory of Digestive DiseasesTianjinChina Department of Urology Tianjin Medical University General HospitalTianjinChina Tianjin Neurological Institution Tianjin Medical University General HospitalTianjinChina

With the rapidly aging human population,age-related cognitive decline and dementia are becoming increasingly prevalent *** is considered the main risk factor for cognitive decline and acts through alterations in the composition of the gut microbiota,microbial metabolites,and the functions of *** microbiota–gut–brain axis has been the focus of multiple studies and is closely associated with cognitive *** article provides a comprehensive review of the specific changes that occur in the composition of the gut microbiota and microbial metabolites in older individuals and discusses how the aging of astrocytes and reactive astrocytosis are closely related to age-related cognitive decline and neurodegenerative *** article also summarizes the gut microbiota components that affect astrocyte function,mainly through the vagus nerve,immune responses,circadian rhythms,and microbial ***,this article summarizes the mechanism by which the gut microbiota–astrocyte axis plays a role in Alzheimer’s and Parkinson’s *** findings have revealed the critical role of the microbiota–astrocyte axis in age-related cognitive decline,aiding in a deeper understanding of potential gut microbiome-based adjuvant therapy strategies for this condition.

关键词： age aging Alzheimer’s disease astrocytes cognitive decline dementia gut microbiota gut–brain axis microbial metabolites neuroinflammation Parkinson’s disease

Overview of in-situ oxygen production technologies for lunar resources

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 233-255页

作者： Youpeng Xu Sheng pang liangwei Cong Guoyu Qian Dong Wang Laishi li Yusheng Wu Zhi Wang College of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China CAS Key Laboratory of Green Process and Engineering National Engineering Research Center for Green Recycling of Strategic Metal ResourcesInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial ***,crucial for supporting human life on the Moon,can be extracted from lunar regolith,which is highly rich in oxygen and contains polymetallic *** oxygen and metal extraction can be achieved using existing metallurgical ***,the ample reserves of water ice on the Moon offer another means for oxygen *** paper offers a detailed overview of the leading technologies for achieving oxygen production on the Moon,drawing from an analysis of lunar resources and environmental *** delves into the principles,processes,advantages,and drawbacks of water-ice electrolysis,two-step oxygen production from lunar regolith,and one-step oxygen production from lunar *** two-step methods involve hydrogen reduction,carbothermal reduction,and hydrometallurgy,while the one-step methods encompass fluorination/chlorination,high-temperature decomposition,molten salt electrolysis,and molten regolith electrolysis(MOE).Following a thorough comparison of raw materials,equipment,technology,and economic viability,MOE is identified as the most promising approach for future in-situ oxygen production on the *** the corrosion characteristics of molten lunar regolith at high temperatures,along with the Moon's low-gravity environment,the development of inexpensive and stable inert anodes and electrolysis devices that can easily collect oxygen is critical for promoting MOE technology on the *** review significantly contributes to our understanding of in-situ oxygen production technologies on the Moon and supports upcoming lunar exploration initiatives.

关键词： lunar resources in-situ oxygen production space metallurgy molten lunar regolith electrolysis

入射光调制对Ce：KNSBN晶体两波耦合的影响

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光子学报 2008年第3期37卷 585-588页

作者：李盼来郭庆林李红莲王志军张金平梁宝来庞立斌河北大学物理科学与技术学院河北保定071002 河北大学质量技术监督学院河北保定071002

研究了入射光调制条件下Ce∶KNSBN晶体两波耦合动态过程.结果表明,入射光调制抑制了光扇噪音对Ce∶KNSBN晶体两波耦合动态过程的影响,提高了透射信号光强度.同时研究了入射光光强比Ip/Is及入射光总光强Io对最佳调制频率及增益改善Gm/Gf... 详细信息

研究了入射光调制条件下Ce∶KNSBN晶体两波耦合动态过程.结果表明,入射光调制抑制了光扇噪音对Ce∶KNSBN晶体两波耦合动态过程的影响,提高了透射信号光强度.同时研究了入射光光强比Ip/Is及入射光总光强Io对最佳调制频率及增益改善Gm/Gf的影响.结果显示,同一Io下,Ip/Is为100时,Gm/Gf到达峰值1.52,对应的最佳调制频率为150Hz;同一Ip/Is下,Io为57mW/cm2时,Gm/Gf最大为1.53,对应的最佳调制频率为175Hz.

关键词： Ce:KNSBN晶体两波耦合光扇效应入射光调制

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飞行器高速气流流经空腔对噪声抑制优化仿真

计算机仿真 2017年第6期34卷 51-56页

作者：李红丽庞彦宾侯峰刘兴强中航工业飞机强度研究所陕西西安710065

高速气流流经飞行器空腔,会产生强烈的气动噪声,对空腔结构造成很大的威胁。传统噪声抑制方法(如前缘吹气、扰流板、射流等)主要通过改变空腔的流场,达到抑制噪声的且的,但结构复杂,且破坏空腔外部构型,因此需要寻找新的噪声抑制方法。... 详细信息

高速气流流经飞行器空腔,会产生强烈的气动噪声,对空腔结构造成很大的威胁。传统噪声抑制方法(如前缘吹气、扰流板、射流等)主要通过改变空腔的流场,达到抑制噪声的且的,但结构复杂,且破坏空腔外部构型,因此需要寻找新的噪声抑制方法。基于可控阻抗边界的噪声抑制方法,无需引入额外装置。采用仿真方法对声阻抗抑制空腔噪声可行性进行了研究,通过对比分析空腔底面不同测点的声压频谱特性,研究了不同壁面声阻抗值对空腔噪声的抑制效果。研究结果表明:利用声阻抗能够有效抑制空腔的前三阶峰值噪声,空腔后缘产生的噪声在向前传播过程中有所衰减,具有良好的工程应用前景。

关键词：空腔气动噪声声阻抗抑制方法声压级

Interannual variability of boreal summer intraseasonal oscillation over the northwestern Pacific influenced by the Pacific Meridional Mode

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 6-11页

作者： Haoyu Zhou pang-Chi Hsu lin Chen Yitian Qian Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environmental Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjingChina

During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the subtropical Northwestern Pacific(10°-20°N,130°E-175°W).The former is well-documented and considered to be influenced by the ENSO,while the latter has received comparatively less attention and is likely influenced by the Pacific Meridional Mode(PMM),as suggested by partial correlation analysis *** elucidate the physical processes responsible for the enhanced(weakened)intraseasonal convection over the subtropical northwestern Pacific during warm(cold)PMM years,the authors employed a moisture budget *** findings reveal that during warm PMM years,there is an increase in summer-mean moisture over the subtropical northwestern *** increase interacts with intensified vertical motion perturbations in the region,leading to greater vertical moisture advection in the lower troposphere and consequently resulting in convective *** a process is pivotal in amplifying intraseasonal convection *** observational findings were further verified by model experiments forced by PMM-like sea surface temperature patterns.

关键词： Boreal summer intraseasonal oscillation Interannual variability Pacific Meridional Mode Moisture budget analysis

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对武术散打运动30年科研现状的回顾与反思

搏击(武术科学) 2010年第2期7卷 55-57页

作者：庞兵武李斌河南大学体育学院

文章采用文献资料、数理统计和逻辑分析方法,对1979年——2009年这30年间国内公开发行的13种中文体育核心期刊中有关散打方面的论文进行统计分析,研究发现:30年间散打的论文发表量呈阶梯式上升状态,对散打运动员选材、运动损伤和市场化... 详细信息

文章采用文献资料、数理统计和逻辑分析方法,对1979年——2009年这30年间国内公开发行的13种中文体育核心期刊中有关散打方面的论文进行统计分析,研究发现:30年间散打的论文发表量呈阶梯式上升状态,对散打运动员选材、运动损伤和市场化运作方面的研究成果比较少;在技术训练的研究成果中,对拳法和步法的技术训练的研究成果十分匮乏,来自散打运动训练与竞赛第一线的研究者较少。文章依据以上散打科研现状,提出了一些理论建议,为散打运动向着更加科学化的方向发展提供参考。

关键词：散打科研现状回顾

Bi^3＋激活的Sr2SiO4材料发光特性研究

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硅酸盐通报 2008年第1期27卷 67-70页

作者：李盼来庞立斌高少杰王志军杨志平熊志军河北大学物理科学与技术学院保定071002 河北大学外语教研部保定071002

采用溶胶-凝胶法制备了Sr2SiO4∶Bi3+发光材料。X射线衍射谱显示其为纯相的Sr2SiO4晶体。测量了Sr2SiO4∶Bi3+材料的激发与发射光谱,结果显示,材料的发射光谱为一单峰宽带,主峰位于441nm处;监测441nm发射峰,所得材料的激发光谱为一主峰... 详细信息

采用溶胶-凝胶法制备了Sr2SiO4∶Bi3+发光材料。X射线衍射谱显示其为纯相的Sr2SiO4晶体。测量了Sr2SiO4∶Bi3+材料的激发与发射光谱,结果显示,材料的发射光谱为一单峰宽带,主峰位于441nm处;监测441nm发射峰,所得材料的激发光谱为一主峰位于376nm处的单峰宽带。研究了Bi3+掺杂浓度对Sr2SiO4∶Bi3+材料发射光谱的影响,结果显示,随Bi3+掺杂浓度的增大,Sr2SiO4∶Bi3+材料的发射光谱峰值强度表现出先增大后减小的趋势,在Bi3+掺杂物质的量浓度为3%时,可获得最大的峰值强度。加入电荷补偿剂li+、Na+和K+,均提高了Sr2SiO4∶Bi3+材料发射光谱峰值强度,其中以加入li+的情况最明显。

关键词： Sr2SiO4∶Bi^3+ 发光特性 Bi^3+ 电荷补偿