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350 km/h高速铁路半封闭声屏障脉动风压时变特性研究

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铁道标准设计 2025年第2期69卷 191-197+214页

作者：韩珈琪潘晓岩吉晓宇敬海泉中国铁路设计集团有限公司机械动力与环境工程设计研究院中南大学土木工程学院

近年来，高速铁路运行速度不断提升，列车产生的噪声急剧增加，影响到附近居民的生活。半封闭声屏障广泛应用在高速铁路噪声治理中，由于半封闭声屏障结构的不对称性，导致列车通过时其空气动力学特性更加复杂，亟需深入研究。采用Fluen... 详细信息

近年来，高速铁路运行速度不断提升，列车产生的噪声急剧增加，影响到附近居民的生活。半封闭声屏障广泛应用在高速铁路噪声治理中，由于半封闭声屏障结构的不对称性，导致列车通过时其空气动力学特性更加复杂，亟需深入研究。采用Fluent流体力学分析软件，建立三维数值模型，模拟速度350 km/h高速列车通过半封闭声屏障时声屏障壁面的风压分布情况，系统研究声屏障壁面脉动风压的时变特性和正负压力极值空间的分布规律，以及声屏障长度、截面形式和列车速度对声屏障壁面脉动风压的影响。结果表明，列车高速通过声屏障时壁面风压呈现明显的头波和尾波效应，声屏障壁面同一截面的风压随测点高度逐渐减小，沿长度方向正峰值出现在距离入口约5 m位置处，负峰值出现在距离入口和出口约5 m位置处，正负压力极值在中间区域基本相等；半封闭声屏障的长度对壁面风压的时程及空间分布无显著影响，半封闭声屏障截面形式对声屏障壁面风压时变趋势的影响较小，并且不同截面形式半封闭声屏障的壁面风压峰值分布情况基本一致；车速对声屏障壁面脉动风压影响显著，正峰值及负峰值近似与车速的平方成正比。研究结果可为半封闭声屏障的结构设计提供参考。

关键词：高速铁路半封闭声屏障脉动风压计算流体力学时变特性空间分布规律

Benfotiamine prevents increased β-amyloid production in HEK cells induced by high glucose

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Neuroscience Bulletin 2012年第5期28卷 561-566页

作者： xiao-jing Sun Lei Zhao Na Zhao xiao-Li pan Guo-Qiang Fei Li-Rong Jin Chun-Jiu Zhong Department of Neurology Zhongshan Hospital & Shanghai Medical College Fudan University Shanghai 200032 China State Key Laboratory of Medical Neurobiology Institute of Brain Science Fudan University Shanghai 200032 China

Objective To determine whether high glucose enhances β-amyloid （Aβ） production in HEK293 Swedish mutant （APPsw） cells with Aβ precursor protein （APP） overexpression, and whether under this condition benfotiamine reduces the increased Aβ production. Methods HEK293 APPsw cells were cultured with different concentrations of glucose for different times. TheAβ content in the supernatant was determined by ELISA. To investigate the mechanism by which benfotiamine reduced Aβ production, glycogen synthase kinase-3 （GSK-3） activity and expression were measured after the cells were cultured with 5.5 g/L glucose for 12 h. Results With 1.0, 3.0, 4.5, 5.5, 6.5, 7.5, 8.5, or 10.5 g/L glucose, Aβ production by HEK293 APPsw cells was highest in the presence of 5.5 g/L glucose for 6 and 12 h. The difference in Aβ content between 5.5 and 1.0 g/L was most marked after incubation for 12 h. Benfotiamine at 20 and 40 μg/mL significantly reduced Aβ production in cells incubated with 5.5 g/L glucose for 12 h. Moreover, 40 μg/mL benfotiamine significantly enhanced the ratio of phosphorylated GSK-3 to total GSK-3, together with consistent down-regulation of GSK-3 activity. Conclusion High glucose increases Aβ production by HEK293 APPsw cells while benfotiamine prevents this increase. This is correlated with the modulation of GSK-3 activity.

关键词： Alzheimer’s disease β-amyloid high glucose benfotiamine glycogen synthase kinase

Synthesis of Nitrogen-Doped Graphene via Thermal Annealing Graphene with Urea

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Chinese Journal of Chemical Physics 2012年第3期25卷 325-329,374页

作者： Xin-jing Li Xin-xin Yu Jin-yang Liu xiao-dong Fan Kun Zhang Hong-bing Cai Nan pan xiao-ping Wang Department of Physics University of Science and Technology of China Hefei 230026 China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Tech-nology of China Hefei 230025 China

Chemical doping is an effective method to intrinsically modify the chemical and electronic property of graphene. We propose a novel approach to synthesize the nitrogen-doped graphene via thermal annealing graphene with urea, in which the nitrogen source can be controllably released from the urea by varying the annealed temperature and time. The doped N content and the configuration N as well as the thermal stabilities are also evaluated with X-ray photoelectron spectroscopy and Raman spectra. Electrical measurements indi- cate that the conductivity of doped graphene can be well regulated with the N content. The method is expected to produce large scale and controllable N-doped graphene sheets for a variety of potential applications.

关键词： Graphene Doping Conductivity X-ray photoelectron spectroscopy Ramanspectrum

Influence of Ce on Characteristics of Inclusions and Microstructure of Pure Iron

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Journal of Iron and Steel Research International 2011年第2期18卷 38-44页

作者： WEN Bin SONG Bo pan Ning SHU Qi-feng HU xiao-jun MAO jing-hong School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China Key Laboratory of Ecological and Recycling Metallurgy University of Science and Technology Beijing Beijing 100083 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The experiments on adding Ce, Mn and S to molten iron have been carried out by means of the electric furnace, and the concentration of oxygen, the evolution of inclusions and microstructures of samples are analyzed, indicating that the concentration of dissolved oxygen decreases greatly after adding Ce. The calculated thermodynamics results at 1 273 K performed on Factsage show that Ce2O2S and CeAlO3 are formed with the increase of Ce content for w（Ce）〉0. 000 2 and w（S）〈0. 000 1, while three cerium sulphides （CeS, Ce3S4 and Ce2S3 , in sequence）, MnS and Ce2 O2 S are formed with the increase of S content and the decrease of Ce content for w（Ce）〉0. 000 2 and w（S）〉 0. 000 1. These results are consistent with the SEM observations. Finally, some possible reasons are given to explain the formation of intragranular ferrite in the pure iron.

关键词： Ce inclusion intragranular ferrite deoxidation

DNA tetrahedron-mediated immune-sandwich assay for rapid and sensitive detection of PSA through a microfluidic electrochemical detection system

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Microsystems & Nanoengineering 2021年第2期7卷 221-230页

作者： Dezhi Feng jing Su Yi Xu Guifang He Chenguang Wang xiao Wang Tingrui pan Xianting Ding Xianqiang Mi Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences200050ShanghaiChina Shanghai Advanced Research Institute Chinese Academy of Sciences201210ShanghaiChina University of Chinese Academy of Sciences 100049BeijingChina State Key Laboratory of Oncogenes and Related Genes Institute for Personalized MedicineSchool of Biomedical EngineeringShanghai Jiao Tong University200030ShanghaiChina School of Life Sciences Shanghai University200444ShanghaiChina Shenzhen Institutes of Advanced Technology Chinese Academy of Science518055ShenzhenChina CAS Center for Excellence in Superconducting Electronics (CENSE)200050ShanghaiChina Key Laboratory of Systems Health Science of Zhejiang Province Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesChinese Academy of Sciences310024HangzhouChina

Prostate-specific antigen(PSA)is the most widely used biomarker for the early diagnosis of prostate *** methods for PSA detection are burdened with some limitations and require ***,we developed a novel microfluidic–electrochemical(μFEC)detection system for PSA ***,we constructed an electrochemical biosensor based on screen-printed electrodes(SPEs)with modification of gold nanoflowers(Au NFs)and DNA tetrahedron structural probes(TSPs),which showed great detection ***,we fabricated microfluidic chips by DNA TSP-Au NF-modified SPEs and a PDMS layer with designed dense meandering ***,theμFEC detection system was achieved based on microfluidic chips integrated with the liquid automatic conveying unit and electrochemical detection ***μFEC system we developed acquired great detection performance for PSA detection in PBS *** PSA assays in spiked serum samples of theμFEC system,we obtained a linear dynamic range of 1–100 ng/mL with a limit of detection of 0.2 ng/mL and a total reaction time<25 *** serum samples of prostate cancer patients presented a strong correlation between the“gold-standard”chemiluminescence assays and theμFEC *** terms of operation procedure,cost,and reaction time,our method was superior to the current methods for PSA detection and shows great potential for practical clinical application in the future.

关键词： fluid diagnosis system

丁苯酚辅助尤瑞克林对大动脉粥样硬化型脑卒中患者脑血管储备功能及氧化应激指标的影响

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四川生理科学杂志 2025年第1期47卷 77-79,188页

作者：潘德雾黄晶大余县人民医院神经内科江西赣州341500 大余县人民医院神经外科江西赣州341500

目的:探究丁苯酚辅助尤瑞克林对大动脉粥样硬化型脑卒中患者脑血管储备功能及氧化应激指标的影响。方法:选取2022年1月至2024年1月期间收治的60例大动脉粥样硬化型脑卒中患者,采用随机掷硬币法将患者随机分为各30例的常规组(给予常规药... 详细信息

目的:探究丁苯酚辅助尤瑞克林对大动脉粥样硬化型脑卒中患者脑血管储备功能及氧化应激指标的影响。方法:选取2022年1月至2024年1月期间收治的60例大动脉粥样硬化型脑卒中患者,采用随机掷硬币法将患者随机分为各30例的常规组(给予常规药物治疗加上尤瑞克林治疗)和联合组(在常规组基础上加上丁苯酚治疗)。在患者治疗前和治疗3 w w后比较两组的神经功能(美国国立卫生研究院卒中量表评分)、血管储备能力(搏动指数值、储备功能值、屏气指数)及氧化应激指标水平(血清丙二醛水平、超氧化物歧化酶水平)。结果:用药结束后,联合组患者卒中量表评分、搏动指数值、血清丙二醛水平均低于常规组,储备功能值、屏气指数和超氧化物歧化酶水平高于常规组(P均0.05)。结论:丁苯酚辅助尤瑞克林能够明显改善大动脉粥样硬化型脑卒中患者的神经功能、脑血管储备功能及氧化应激指标水平,且具备安全性。

关键词：丁苯酚尤瑞克林大动脉粥样硬化型脑卒中血管储备功能氧化应激

Late-Time Evolution of the Phantom Scalar Perturbation in the Background of a Spherically Symmetric Static Black Hole

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Chinese Physics Letters 2010年第6期27卷 9-12页

作者： pan Qi-Yuan jing Ji-Liang Institute of Physics and Department of Physics Hunan Normal University Changsha 410081

The late-time evolution of the phantom scalar perturbation is investigated in the spacetime of a four-dimensionai spherically symmetric static black hole. It is revealed that the asymptotic tail of the phantom scalar field is dominated by the growth behavior t-（l＋3/2）eμt, which depends on the multipole moment l and the field moss but is independent of the mass M and charge Q of the black hole. This growth behavior is in strong contrast to the decaying tall of the usual massive scalar perturbation and shows that the external phantom scalar perturbation is unstable in the spherically symmetric static black hole spacetime.

关键词： Limonium sinuatum Growth Tail Fields

Preserving details in semantics-aware context for scene parsing

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Science China(Information Sciences) 2020年第2期63卷 79-92页

作者： Shuai MA Yanwei panG jing pan Ling SHAO Tianjin Key Laboratory of Brain-Inspired Intelligence Technology School of Electrical and Information EngineeringTianjin University School of Electronic Engineering Tianjin University of Technology and Education

Great success of scene parsing(also known as, semantic segmentation) has been achieved with the pipeline of fully convolutional networks(FCNs). Nevertheless, there are a lot of segmentation failures caused by large similarities between local appearances. To alleviate the problem, most of existing methods attempt to improve the global view of FCNs by introducing different contextual modules. Though the reconstructed high resolution output of these methods is of rich semantics, it cannot faithfully recover the fine image details owing to lack of desired precise low-level information. To overcome the problem, we propose to improve the spatial decoding process through embedding possibly lost low-level information in a principled way. To this end, we make the following three contributions. First, we propose a semantics conformity module to make low-level features variations agnostic. Second, we introduce semantics into the conformed low level features through guidance from semantically aware features. Finally, we institute the availability of various possible contextual features at feature fusion to enrich context information. The proposed approach demonstrates competitive performance on challenging PASCAL VOC 2012, Cityscapes,and ADE20K benchmarks in comparison to the state-of-the-art methods.

关键词： fully convolutional networks semantic segmentation cityscapes semantic-aware context

A New Comparison Theorem of Multidimensional BSDEs

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Acta Mathematicae Applicatae Sinica 2015年第1期31卷 131-138页

作者： pan-yu WU Zeng-jing CHEN Qilu Securities Institute for Financial Studies Shandong University School of Mathematics Shandong University

In this paper, we first study a property about the generator g of Backward Stochastic Differential Equation （BSDE） when the price of contingent claims can be represented by a multidimensional BSDE in the no-arbitrage financial market. Furthermore, motivated by the behavior of agents in finance market, we introduce a new total order q on Rn and obtain a necessary and sufficient condition for comparison theorem of multidimensional BSDEs under this order. We also give some further results for q

关键词： backward stochastic differential equation comparison theorem viability property