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Investigation on the stall types in impellers with different blade numbers

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Journal of Hydrodynamics 2023年第2期35卷 299-313页

作者： Xiao-dong Liu Yao-jun Li zhu-qing Liu wei Yang College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System China Agricultural UniversityBeijing100083China

Stall is a complex flow phenomenon and its existence usually shows significant differences in different impeller *** this paper,the flow field characteristics and mechanism of stall types in impellers with different blade numbers were studied through the combination of experiment and numerical simulation at stall inception *** the experiments,it was observed that the five-blade impeller entered the rotating stall stage from a relatively stable flow field within a small flow rate *** the six-blade impeller,the root cause that stall vortices appeared in channels alternately rather than each one evenly was also reasonably *** validated numerical simulation method was utilized to reveal the three-dimensional flow field in impeller *** results indicate the swirling vortex near the impeller shroud was periodically sucked in and escaped from region near the blade suction side,which was the fundamental driving force of rotating *** sudden change of flow field caused by the fusion of the separation vortex at the channel inlet and the vortex induced by the swirling vortex near shroud is the essential reason for the formation of alternating ***’s more,the stall inception flow field is clearly defined in impellers,which is of great significance for the further analysis of stall *** on the distribution characteristics of vortex structure near impeller shroud with different blade numbers at different flow rate conditions,this paper deeply investigated the formation mechanism of different stall types in impellers.

关键词： Numerical simulation high-frequency particle image velocimetry(PIV) impellers swirling vortex stall type

Segmentation by Elastica Energy with L^(1) and L^(2) Curvatures: a Performance Comparison

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Numerical Mathematics(Theory,Methods and Applications) 2019年第1期12卷 285-311页

作者： Xuan He wei zhu xue-Cheng Tai Department of Mathematics University of AlabamaBox 870350TuscaloosaAL 35487USA Department of Mathematics Hong Kong Baptist UniversityKowloonTong KowloonHong Kong

In this paper,we propose an algorithm based on augmented Lagrangian method and give a performance comparison for two segmentation models that use the L^(1)-and L^(2)-Euler’s elastica energy respectively as the regularization for image *** capture contour curvature more reliably,we develop novel augmented Lagrangian functionals that ensure the segmentation level set function to be signed dis-tance functions,which avoids the reinitialization of segmentation function during the iterative *** the proposed algorithm and with the same initial contours,we compare the performance of these two high-order segmentation models and numerically verify the different properties of the two models.

关键词： Augmented Lagrangian method Euler’s elastica image segmentation

CSPP1 stabilizes microtubules by capping both plus and minus ends

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Journal of Molecular Cell Biology 2024年第2期16卷 36-46页

作者： Zhikai Wang Wenwen Wang Shuaiyu Liu Fengrui Yang Xu Liu Shasha Hua Lĳuan zhu Aoqing Xu Donald LHill Dongmei Wang Kai Jiang Jennifer Lippincott-Schwartz Xing Liu xuebiao Yao MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics Center for Advanced Interdisciplinary Science and Biomedicine of IHMUniversity of Science and Technology of China School of Life SciencesHefei 230027China Anhui Key Laboratory for Cellular Dynamics and Chemical Biology Hefei National Research Center for Interdisciplinary Sciences at the MicroscaleHefei 230027China Frontier Science Center for Immunology and Metabolism Medical Research InstituteWuhan UniversityWuhan 430071China Comprehensive Cancer Center University of AlabamaBirminghamAL 35233USA Janelia Research Campus Howard Hughes Medical InstituteAshburnVA 20147USA

Although the dynamic instability of microtubules(MTs)is fundamental to many cellular functions,quiescent MTs with unattached free distal ends are commonly present and play important roles in various events to power cellular ***,how these free MT tips are stabilized remains poorly ***,we report that centrosome and spindle pole protein 1(CSPP1)caps and stabilizes both plus and minus ends of static ***-time imaging of laser-ablated MTs in live cells showed deposition of CSPP1 at the newly generated MT ends,whose dynamic instability was concomitantly ***,MT ends in CSPP1-overexpressing cells were hyper-stabilized,while those in CSPP1-depleted cells were much more *** CSPP1-elicited stabilization of MTs was demonstrated to be achieved by suppressing intrinsic MT catastrophe and restricting ***,CSPP1-bound MTs were resistant to mitotic centromere-associated kinesin-mediated *** findings delineate a previously uncharacterized CSPP1 activity that integrates MT end capping to orchestrate quiescent MTs.

关键词： CSPP1 microtubule plus end minus end capping

SARS-CoV-2 breakthrough infections following inactivated vaccine vaccination induce few neutralizing antibodies against the currently emerging Omicron XBB variants

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Virologica Sinica 2024年第1期39卷 173-176页

作者： Fan Shen Chun Liang Cui-Xian Yang Ying Lu An-Qi Li Ying Duan Mi Zhang c Ren-Rong Tian a Xing-Qi Dong Yong-Tang Zheng wei Pang Key Laboratory of Bioactive Peptides of Yunnan Province/Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common DiseasesKunming Institute of ZoologyChinese Academy of SciencesKunming650223China University of Chinese Academy of Sciences Beijing100049China Yunnan Provincial Infectious Disease Hospital Kunming650399China Department of Pathogen Biology and Immunology Faculty of Basic Medical ScienceKunming Medical UniversityKunming650500China

Dear Editor,COVID-19 inactivated vaccines have been extensively administered ***,the majority of the Chinese population has experiencedbreakthrough infections from SARS-CoV-2 ancestral,Delta or Omicronvariants over the past three years,particularly during the wave of Omicron BA.5 and BA.7 variants at the end of 2022(zhu et al.,2023).Subsequently,new Omicron variants,such as BQ.1,BQ.1.1,XBB,XBB.1/XBB.1.9,and XBB.1.5/XBB.1.9.1,are emerging in China(Yueetal.,2023;zhu et al.,2023).Therefore,it is an urgentneed and a publichealth imperative to assess the extent of the immunoprotection established in this population.

关键词： breakthrough neutral Omi

针刀联合正骨治疗颈性眩晕临床疗效的Meta分析

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世界中西医结合杂志 2024年第7期19卷 1305-1311页

作者：宋雪居宇斌叶芊严一成曾翡翠朱烱伟上海中医药大学附属上海市中西医结合医院骨伤一科上海200082

目的系统评价针刀联合正骨治疗颈性眩晕的临床疗效,为治疗颈性眩晕的临床决策提供循证参考。方法检索2013年1月1日-2023年12月31日期间中国生物医学数据库(SinoMed)、中国知网、万方数据库、维普数据库、PubMed等数据库中收录的针刀联... 详细信息

目的系统评价针刀联合正骨治疗颈性眩晕的临床疗效,为治疗颈性眩晕的临床决策提供循证参考。方法检索2013年1月1日-2023年12月31日期间中国生物医学数据库(SinoMed)、中国知网、万方数据库、维普数据库、PubMed等数据库中收录的针刀联合正骨治疗颈性眩晕相关的随机对照研究文献。分层筛选,将所纳文献行数据提取并予质量评价,采用RevMan5.3,Stata14.0统计学软件进行Meta分析。结果共有27篇文献符合纳入标准,共2481例患者。Meta分析结果:观察组总有效率优于对照组(P<0.00001);观察组左、右椎动脉,基底动脉血流速度改善程度均优于对照组(P<0.00001);观察组相较其他疗法能有效改善颈X线影像学指标(P<0.001);观察组在改善颈性眩晕症状与功能评分方面较对照组有明显优势(P<0.05)。结论针刀联合正骨相较其他疗法可显著提高临床有效率、改善其临床症状、疼痛程度、椎基底动脉血流速度及影像学指标,提示临床治疗颈性眩晕可优先采用针刀联合正骨方法。

关键词：颈性眩晕椎动脉型颈椎病正骨针刀 Meta分析

硫化温度对固体火箭发动机绝热层性能的影响研究

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火工品 2024年第3期 47-53页

作者：沈肖胤刘海亮温彦威朱利勤朱毅凌时志权万洪博上海航天动力技术研究所浙江湖州313000 海军装备部驻上海地区第六军代表室浙江湖州313000

针对同一配方固体火箭发动机绝热层,开展了测试温度对未硫化绝热层粘度、未硫化绝热层初期硫化的影响,以及硫化温度对绝热层性能、绝热层界面粘接效果、绝热层高分子结构以及抗烧蚀性能的影响。结果表明:随测试温度的升高绝热层试样的... 详细信息

针对同一配方固体火箭发动机绝热层,开展了测试温度对未硫化绝热层粘度、未硫化绝热层初期硫化的影响,以及硫化温度对绝热层性能、绝热层界面粘接效果、绝热层高分子结构以及抗烧蚀性能的影响。结果表明:随测试温度的升高绝热层试样的门尼粘度值(ML)降低,硫化T5、T35时间缩短;在相同硫化条件下,硫化温度对绝热层本体的力学性能具有直接且显著的影响,且影响效果与测试环境温度直接相关;硫化温度越高,绝热层的玻璃化温度越高,但硫化温度对绝热层热分解性能没有影响;硫化温度对绝热层试样界面粘接性能、抗烧蚀性能有直接影响,分析证实170℃硫化温度下,绝热层已过度硫化。

关键词：硫化温度力学性能交联密度界面粘接玻璃化温度烧蚀性能

基于线性自抗扰控制的纵向舰载机直接升力全自动着舰控制

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智能系统学报 2024年第1期19卷 142-152页

作者：吴启龙朱齐丹哈尔滨工程大学智能科学与工程学院黑龙江哈尔滨150001

舰载机的最终着舰过程受到强烈的舰尾流的干扰,为了抑制舰尾流扰动,本文提出一种基于径向基函数神经网络(radial basis functions neural network,RBFNN)结合线性自抗扰控制(liner active disturbance rejection control,LADRC)的创新... 详细信息

舰载机的最终着舰过程受到强烈的舰尾流的干扰,为了抑制舰尾流扰动,本文提出一种基于径向基函数神经网络(radial basis functions neural network,RBFNN)结合线性自抗扰控制(liner active disturbance rejection control,LADRC)的创新设计方法,确保舰载机直接升力控制自动着舰系统的鲁棒性。LADRC将阵风扰动和系统不确定项作为总扰动,通过线性扩展状态观测器(liner extended state observer,LESO)对总扰动进行估计,并通过线性反馈控制律进行补偿,然后根据系统状态利用RBFNN在线调整LADRC控制器的参数,并构建Lyapunov函数以证明闭环系统的稳定性。舰载机跟踪理想下滑道的仿真结果表明,RBF-LADRC的抗干扰性、鲁棒性和跟踪精度均优于与之对比的控制方法。

关键词：稳定性分析直接升力控制径向基函数神经网络线性自抗扰控制自动着舰姿态控制舰尾流轨迹跟踪

Ultra-low power IGZO optoelectronic synaptic transistors for neuromorphic computing

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Science China(Information Sciences) 2024年

作者： Li zhu Sixian LI Junchen LIN Yuanfeng ZHAO Xiang WAN Huabin SUN Shancheng YAN Yong XU Zhihao YU Chee Leong TAN Gang HE College of Integrated Circuit Science and Engineering Nanjing University of Posts and Telecommunications School of Materials Science and Engineering Anhui University

Inspired by biological visual systems, optoelectronic synapses with image perception, memory retention, and preprocessing capabilities offer a promising pathway for developing high-performance artificial perceptual vision computing systems. Among these, oxide-based optoelectronic synaptic transistors are wellknown for their enduring photoconductive properties and ease of integration, which hold substantial potential in this regard. In this study, we utilized indium gallium zinc oxide as a semiconductor layer and high-k ZrAlOx as a gate dielectric layer to engineer low-power high-performance synaptic transistors with photonic *** biological synaptic functions, including excitatory postsynaptic currents, paired-pulse facilitation,and the transition from short-term to long-term plasticity, were replicated via optical pulse *** simulation was sustained even at an operating voltage as low as 0.0001 V, exhibiting a conspicuous photonic synaptic response with energy consumption as low as 0.0845 fJ per synaptic event. Furthermore,an optoelectronic synaptic device was employed to model “learn-forget-relearn” behavior similar to that exhibited by the human brain, as well as Morse code encoding. Finally, a 3×3 device array was constructed to demonstrate its advantages in image recognition and storage. This study provides an effective strategy for developing readily integrable, ultralow-power optoelectronic synapses with substantial potential in the domains of morphological visual systems, biomimetic robotics, and artificial intelligence.

关键词：

川南地区晚二叠世铌—稀土—钛多金属富集层成因机制及对峨眉山地幔柱成矿系统的补充

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地质论评 2024年第S1期70卷 41-42页

作者：文俊赵伟刘治成张航飞竹合林赵凱莉四川省第七地质大队四川乐山614000 四川省地质矿产勘查开发局张金元劳模创新工作室四川乐山614000 成都理工大学沉积地质研究院成都610059 四川省国土科学技术研究院成都610045

近年来,在川南沐川地区晚二叠世宣威组底部发现了厚度大、高度富集、层位稳定、分布面积广的新类型Nb—REE—Ti多金属富集层,该富集层中超常富集Nb、REE、Ti、Ga、Sc、Zr等多种关键金属元素,此6种战略性关键金属矿产是我国急缺重要的高... 详细信息

近年来,在川南沐川地区晚二叠世宣威组底部发现了厚度大、高度富集、层位稳定、分布面积广的新类型Nb—REE—Ti多金属富集层,该富集层中超常富集Nb、REE、Ti、Ga、Sc、Zr等多种关键金属元素,此6种战略性关键金属矿产是我国急缺重要的高科技矿产,且找矿潜力较大。近30年来,地质工作者广泛关注了晚二叠世峨眉山玄武岩组与宣威组之间的平行不整合界面之上的黏土岩层中“三稀”富集特征与成因.

关键词：铌—稀土—钛多金属富集层宣威组峨眉山玄武岩晚二叠世成因