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级联掺Yb增益光纤提高拍频信号信噪比的实验研究

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物理学报 2017年第2期66卷 168-175页

作者：刘欢曹士英于洋林百科方占军清华大学精密仪器系激光与光子技术研究室北京100084 中国计量科学研究院时间频率计量研究所北京100029

飞秒光学频率梳的出现使对未知激光的绝对频率测量成为可能,极大地简化了激光绝对频率的量值溯源和比对工作.为了保证测量数值的准确性,飞秒光学频率梳与未知激光的拍频信号fb的信噪比要求大于30 d B.针对碘稳频532 nm激光绝对频率测量... 详细信息

飞秒光学频率梳的出现使对未知激光的绝对频率测量成为可能,极大地简化了激光绝对频率的量值溯源和比对工作.为了保证测量数值的准确性,飞秒光学频率梳与未知激光的拍频信号fb的信噪比要求大于30 d B.针对碘稳频532 nm激光绝对频率测量的特定需求,以532 nm激光的基频光1064 nm激光的绝对频率测量为着眼点,本文采用303 MHz重复频率的掺Er光纤光学频率梳,首先通过激光放大和光谱展宽技术使光谱覆盖到1μm波段,然后采用级联掺Yb增益光纤技术,将扩谱后1μm波段的激光功率进行放大,提高了掺Er光纤光学频率梳扩谱后1μm波长附近的激光强度.采用碘稳频532 nm激光的基频光作为待测光源与飞秒光学频率梳进行拍频.实验表明,与未经过光谱增强的激光相比,光谱增强后的激光与1064 nm激光拍频信号的信噪比提高了5 d B,保持在35 d B附近.该技术有效地缓解了采用掺Er光纤光梳测量1064 nm激光绝对频率时对直接扩谱所获得的1μm波长激光的强度要求.

关键词：掺Er光纤飞秒激光器光谱增强拍频信号光纤光学频率梳

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang Feng Gao yu-Gui Peng Peng Wu Zong-lin Li Xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

Targeting TrkB–PSD-95 coupling to mitigate neurological disorders

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Neural Regeneration Research 2025年第3期20卷 715-724页

作者： Xin yang yu-Wen Alvin Huang John Marshall Department of Molecular Biology Cell Biology and BiochemistryBrown UniversityProvidenceRIUSA Department of Neurology Warren Alpert Medical School of Brown UniversityProvidenceRIUSA Center for Translational Neuroscience Robert J.and Nancy D.Carney Institute for Brain Science and Brown Institute for Translational ScienceBrown UniversityProvidenceRIUSA

Tropomyosin receptor kinase B(TrkB)signaling plays a pivotal role in dendritic growth and dendritic spine formation to promote learning and *** activity-dependent release of brain-derived neurotrophic factor at synapses binds to pre-or postsynaptic TrkB resulting in the strengthening of synapses,reflected by long-term ***,the association of postsynaptic density protein-95 with TrkB enhances phospholipase Cγ-Ca^(2+)/calmodulin-dependent protein kinaseⅡand phosphatidylinositol 3-kinase-mechanistic target of rapamycin signaling required for long-term *** this review,we discuss TrkB-postsynaptic density protein-95 coupling as a promising strategy to magnify brain-derived neurotrophic factor signaling towards the development of novel therapeutics for specific neurological disorders.A reduction of TrkB signaling has been observed in neurodegenerative disorders,such as Alzheimer's disease and Huntington's disease,and enhancement of postsynaptic density protein-95 association with TrkB signaling could mitigate the observed deficiency of neuronal connectivity in schizophrenia and *** with brain-derived neurotrophic factor is problematic,due to poor pharmacokinetics,low brain penetration,and side effects resulting from activation of the p75 neurotrophin receptor or the truncated TrkB.T1 *** TrkB agonists and antibodies that activate TrkB are being intensively investigated,they cannot distinguish the multiple human TrkB splicing isoforms or cell type-specific *** TrkB–postsynaptic density protein-95 coupling provides an alternative approach to specifically boost TrkB signaling at localized synaptic sites versus global stimulation that risks many adverse side effects.

关键词： Angelman syndrome autism brain-derived neurotrophic factor depression neurodegenerative disorder neurodevelopmental disorder postsynaptic density protein-95 synaptic plasticity TrkB

Nanostructured ZnO/BiVO_(4)I-scheme heterojunctions for piezocatalytic degradation of organic dyes via harvesting ultrasonic vibration energy

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 488-497页

作者： Yiling Li Xiaoyao yu Yingjie Zhou Yao lin Ying Wu Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Materials ScienceZhejiang Normal UniversityJinhua 321004China

BiVO_(4)porous spheres modified by ZnO were designed and synthesized using a facile two-step *** resulting ZnO/BiVO_(4)composite catalysts have shown remarkable efficiency as piezoelectric catalysts for degrading Rhodamine B(RhB)unde mechanical vibrations,they exhibit superior activity compared to pure *** 40wt%ZnO/BiVO_(4)heterojunction composite displayed the highest activity,along with good stability and *** enhanced piezoelectric catalytic activity can be attributed to the form ation of an I-scheme heterojunction structure,which can effectively inhibit the electron-hole ***,hole(h+)and superoxide radical(·O_(2)^(-))are proved to be the primary active ***,ZnO/BiVO_(4)stands as an efficient and stable piezoelectric catalyst with broad potential application in the field of environmental water pollution treatment.

关键词： piezoelectric catalytic heterojunction dye degradation ultrasonic vibration

Study on Epidemic Pattern of Nematode and its larvae on Parasitic phase in yak on Qing-Tibetan Plateau

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Study on Epidemic Pattern of Nematode and its larvae on Para...

中国动物学会寄生虫学专业委员会第十三次全国学术会议暨第四次国际寄生虫学学术研讨会

作者： Jin-Zhong Cai Chun-Hua Li Sheng-Cai Liu yu-lin yang Zhong-Qiang Xie Cai-Rangzhaxi Qinghai Academy of Animal Science and veterinary Medicine

The yak are the mainstay of livelihood for the nomads on the vast Qinghai-Tibetan Plateau of western China and adjacent regions,yak are often communally *** research showed that nutritional deficiencies and parasitic diseases were main causes restricted the development of yak *** nematode parasite usually mixed infection in the yak was an important pathogenic,and it causing enormous economic losses such as dairy production decrease,beef cattle weight loss and even *** explore epidemic law of nematode and establish the effective prevention measures,and improve the economic efficiency of yak husbandry,the studies were carried out in Diri of the Three Rivers,on120 grazing Infant yaks chose random(10 yaks per month were necropsied from 2009 to2010).Skrjabinema method and water bath separating and numbering method were used to study the natural growth and decline rule of yak nematode simultaneously with adult insect and larvae on parasitic phase by yak post-mortem *** results indicated the general rule of yak nematode was that the number of larvae on parasitic phase gradually increased in August to December and reached to high time forth or later and with the peak in December to January next *** with the number of worm dropped in January to June,the number of adult insect in yak gradually rose and formed a obvious parasite high time in spring and mostly in April to *** on parasitic phase in yak dominated in cold season,and adult insect in warm *** this result was similar to the EPG of fecal examinations test.

关键词： Qing-Tibetan plateau yak nematode larvae stage dynamic infection

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论虚假广告侵权归责原则的局限性

云南民族大学学报（哲学社会科学版） 2007年第1期24卷 46-48页

作者：孙学华于林洋云南民族大学成人教育学院云南昆明650031 玉溪师范学院政治法律系云南玉溪653100

实践中,虚假广告侵权一直被视为一般侵权行为,其归责原则适用传统的过错责任原则。实际上,虚假广告侵权在许多方面都有自己的特殊性,这使过错责任原则适用于虚假广告侵权显现出很大的局限性,已经不能很好地发挥法律责任的教育、预防及... 详细信息

实践中,虚假广告侵权一直被视为一般侵权行为,其归责原则适用传统的过错责任原则。实际上,虚假广告侵权在许多方面都有自己的特殊性,这使过错责任原则适用于虚假广告侵权显现出很大的局限性,已经不能很好地发挥法律责任的教育、预防及制裁功能。这种局限性也为虚假广告侵权适用一种更为严格的归责原则创造了条件。

关键词：过错责任虚假广告侵权局限性

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基于低能耗与高缓存命中并存的缓存替换算法

计算机系统应用 2017年第7期26卷 189-194页

作者：胥琳林宇阳浙江工业大学经贸管理学院杭州310058

近年来无线传感器被广泛地利用在各个领域,与之相关的优化节能研究也层出不穷.作为信息共享、分发关键技术的缓存技术节能研究成为了研究热点之一.从缓存替换算法的角度对缓存技术节能进行研究,先对已有的缓存替换算法进行比较分析,在... 详细信息

近年来无线传感器被广泛地利用在各个领域,与之相关的优化节能研究也层出不穷.作为信息共享、分发关键技术的缓存技术节能研究成为了研究热点之一.从缓存替换算法的角度对缓存技术节能进行研究,先对已有的缓存替换算法进行比较分析,在继承二分法思想以及无线传感器网络中缓存替换策略的研究思想的基础上,整合基于低能耗和高缓存命中的两种替换算法,构建出兼顾低能耗和高缓存命中双目标的缓存替换算法.最后通过仿真验证该算法在平均延迟时间、能量消耗以及缓存命中三个方面均有不同程度的提升.

关键词：无线网络缓存替换算法低能耗高缓存命中

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基于BP神经网络的压电陶瓷蠕变预测

计量学报 2017年第4期38卷 429-434页

作者：范伟林瑜阳李钟慎华侨大学机电及自动化学院福建厦门361021

压电陶瓷驱动器的蠕变误差随时间呈现非线性变化,难以实时修正。提出基于BP神经网络的压电陶瓷蠕变预测方法,使用压电陶瓷驱动系统采集数据,对数据进行归一化处理,通过实验设计BP神经网络的隐含层数、隐含层节点数、节点转移函数和训练... 详细信息

压电陶瓷驱动器的蠕变误差随时间呈现非线性变化,难以实时修正。提出基于BP神经网络的压电陶瓷蠕变预测方法,使用压电陶瓷驱动系统采集数据,对数据进行归一化处理,通过实验设计BP神经网络的隐含层数、隐含层节点数、节点转移函数和训练函数,构建BP神经网络预测模型,建立压电陶瓷蠕变与时间的关系。用BP神经网络模型对压电陶瓷蠕变进行了预测仿真,并将结果与实测数据进行了对比。结果表明,蠕变预测结果与实验数据的最大绝对误差均小于0.1μm,最大蠕变误差均不超过0.6%,最大均方误差仅为0.0021,可见,BP预测模型具有较高的预测精度,可作为预测压电陶瓷蠕变误差的一种有效手段。

关键词：计量学压电陶瓷蠕变 BP神经网络预测模型

Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu Cun Liu Yiren yu Guoshu Gao yumeng Zhao Xiongfu Zhang Guodong Liu Guohui yang State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： MFI zeolite ZSM-5 Nanosheets Scale-up synthesis Aromatic alkylation