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P型有限元线法分析扁壳弯曲问题

土木工程学报 1994年第6期27卷 36-44页

作者：袁驷宋涛清华大学

本文从中厚扁壳理论出发,建立高次(次数p可高达14次)扁壳弯曲问题的曲线曲边有限元线法单元.实际计算时,单元尺寸h可以不变,由提高单元次数P来取得比加密单元收敛更快的p收敛.算例表明,本法精度高,收敛快,较理想地克服了剪切闭锁现象,... 详细信息

本文从中厚扁壳理论出发,建立高次(次数p可高达14次)扁壳弯曲问题的曲线曲边有限元线法单元.实际计算时,单元尺寸h可以不变,由提高单元次数P来取得比加密单元收敛更快的p收敛.算例表明,本法精度高,收敛快,较理想地克服了剪切闭锁现象,是一种分析扁壳结构的出色的方法.

关键词：扁壳结构有限元线法弯曲计算

Prospective study of light dark matter search with a newly proposed DarkSHINE experiment

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Science China(Physics,Mechanics & Astronomy) 2023年第1期66卷 124-138页

作者： Jing Chen Ji-yuan Chen Jun-Feng Chen Xiang Chen Chang-Bo Fu Jun Guo Le He Zheng-Ting He Kim siang Khaw Jia-Lin Li Liang Li Shu Li Meng Lv Dan-Ning Liu Han-Qing Liu Kun Liu Qi-Bin Liu Yang Liu Ze-Jia Lu Cen Mo si-yuan song Xiao-Long Wang Yu-Feng Wang Zhen Wang Zi-Rui Wang Wei-Hao Wu Dao Xiang Hai-Jun Yang Jun-Hua Zhang Yu-Lei Zhang Zhi-Yu Zhao Xu-Liang Zhu Chun-Xiang Zhu Yi-Fan Zhu Tsung-DaoLee Institute Shanghai Jiao Tong UniversityShanghai 201210China Institute of Nuclear and Particle Physics School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Key Laboratory for Particle Astrophysics and Cosmology(MOE) Shanghai Key Laboratory for Particle Physics and Cosmology(SKLPPC)Shanghai 200240China Center for High Energy Physics Peking UniversityBeijing 10087lChina School of Mechanical and Electronic Engineering Suzhou UniversitySuzhou 234000China School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China School of Electronics Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China R&D Center Shanghai Instituteof CeramicsChinese Academyof SciencesShanghai 20189China Key Laboratory of Nuclear Physics and lon-beam Application(MOE) Fudan UniversityShanghai 200443China Institute of Modern Physics Fudan UniversityShanghai 200443China IKey Laboratory for Laser Plasmas(MOE) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Zhangjiang Institute for Advanced Study Shanghai JiaoTong UniversityShanghai 200240.China College of Literature Scienceand the ArtsUniversity of MichiganAnn Arbor MI 48109-1040USA Deparment of Physics Swiss Federal Institnute of Technology ZurichZurich 8093Swizerland

Dark photons have been well motivated as strong candidates for dark force carriers and light dark matter in the sub-GeV mass *** with collider experiments,fixed-target experiments provide a complementary approach to searching for dark photons,particularly in the lower mass *** have studied the physics potential of the electron-on-target experiment based on the Shanghai SHINE facility,which provides 10 MHz single electron beam at 8 GeV *** analysis focuses on dark photons being produced via electron and nucleon interaction and then decays to dark matter candidates,which escape detection as missing momentum in the *** experiment takes advantage of using missing momentum to enhance signal versus background separation *** this study,signal samples as a function of dark photon mass and an inclusive background sample with 2.5 billion events are simulated with *** better background estimates,major rare background processes have also been *** paper presents the experiment and detector design,signal and background simulations,analysis strategy,and the prospective study of the experiment *** 9×10^(14) electron-on-target events(about three years running),this experiment is expected to rule out most of the sensitive regions predicted by popular dark photon models.

关键词： dark matter dark photon electron-on-target experiment

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Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 127-135页

作者： Tongyue Li Ziliang Xie Wenjiao Zhou Huan Tong Dawen Yang Anjia Zhang yuan Wu Xiping song State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Whole Win(Beijing)Materials Sci.&Tech.Co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),*** indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the YGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves kinetics

FUBP3 mediates the amyloid-β-induced neuronal NLRP3 expression

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Neural Regeneration Research 2025年第7期20卷 2068-2083页

作者： Jing Yao yuan Li Xi Liu Wenping Liang Yu Li Liyong Wu Zhe Wang Weihong song The National Clinical Research Center for Geriatric Disease Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Neurology The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Pediatrics The Second Affiliated Hospital and Yuying Children’s HospitalKey Laboratory of Alzheimer’s Disease of Zhejiang ProvinceInstitute of AgingWenzhou Medical UniversityWenzhouZhejiang ProvinceChina Oujiang Laboratory(Zhejiang Laboratory for Regenerative Medicine Visionand Brain Health)WenzhouZhejiang ProvinceChina

Alzheimer's disease is characterized by deposition of amyloid-β,which forms extracellular neuritic plaques,and accumulation of hyperphosphorylated tau,which aggregates to form intraneuronal neurofibrillary tangles,in the *** NLRP3 inflammasome may play a role in the transition from amyloid-βdeposition to tau phosphorylation and *** NLRP3 is primarily found in brain microglia,and tau is predominantly located in neurons,it has been suggested that NLRP3 expressed by microglia indirectly triggers tau phosphorylation by upregulating the expression of pro-inflammatory ***,we found that neurons also express NLRP3 in vitro and in vivo,and that neuronal NLRP3 regulates tau *** biochemical methods,we mapped the minimal NLRP3 promoter and identified FUBP3 as a transcription factor regulating NLRP3 expression in *** primary neurons and the neuroblastoma cell line Neuro2A,FUBP3 is required for endogenous NLRP3 expression and tau phosphorylation only when amyloid-βis *** the brains of aged wild-type mice and a mouse model of Alzheimer's disease,FUBP3 expression was markedly increased in cortical *** analysis suggested that FUBP3 plays a role in neuron-mediated immune *** also found that FUBP3 trimmed the 5′end of DNA fragments that it bound,implying that FUBP3 functions in stress-induced *** findings suggest that neuronal NLRP3 may be more directly involved in the amyloid-β-to–phospho-tau transition than microglial NLRP3,and that amyloid-βfundamentally alters the regulatory mechanism of NLRP3 expression in *** that FUBP3 was only expressed at low levels in young wild-type mice and was strongly upregulated in the brains of aged mice and Alzheimer's disease mice,FUBP3 could be a safe therapeutic target for preventing Alzheimer's disease progression.

关键词： 5′end trimming Alzheimer's disease amyloid-beta amyloid-β-dependent transcription FUBP3 inflammasome inflammation neuron NLRP3 tau transcription factor

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基于小波变换的局部化数字水印算法

武汉大学学报（理学版） 2004年第1期50卷 99-103页

作者：杨定楚王思贤袁军宋长安武汉大学电子信息学院湖北武汉430072

为了解决许多水印算法不能抵抗任意剪裁的缺点,提出了局部化数字水印算法.通过二维Mexican Hat小波变换提取图像中的多个特征点,在以特征点为中心的局部化区域中分别进行小波变换,并通过对小波系数进行单系数量化来实现水印信息的嵌入,... 详细信息

为了解决许多水印算法不能抵抗任意剪裁的缺点,提出了局部化数字水印算法.通过二维Mexican Hat小波变换提取图像中的多个特征点,在以特征点为中心的局部化区域中分别进行小波变换,并通过对小波系数进行单系数量化来实现水印信息的嵌入,同时水印的提取不需要原始图像的参与.实验结果表明,在剪裁后待检测图像中至少包含一个嵌入水印区域的前提下,该算法对JPEG、JPEG2000压缩和任意剪裁具有很强的抵抗能力.

关键词：小波变换数字水印局部化特征点提取小区域水印嵌入信息安全

OFDM移动通信系统中的最大多普勒频移估计

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上海交通大学学报 2004年第Z1期38卷 43-45页

作者：司源宋文涛罗汉文蔡觉平上海交通大学电子工程系上海200030

为了估计移动正交频分复用(OFDM)系统中衰落信道下的多普勒干扰,提出了利用OFDM符号的循环前缀检测最大多普勒频移的方法.在已有的单载波系统多普勒估计算法的基础上,结合OFDM符号已有的循环前缀,通过计算循环前缀的归一化自相关函数,... 详细信息

为了估计移动正交频分复用(OFDM)系统中衰落信道下的多普勒干扰,提出了利用OFDM符号的循环前缀检测最大多普勒频移的方法.在已有的单载波系统多普勒估计算法的基础上,结合OFDM符号已有的循环前缀,通过计算循环前缀的归一化自相关函数,得到最大多普勒频移.在衰落信道下的计算机仿真结果表明,该算法可以准确地估计出最大多普勒频移.该方法只需利用OFDM符号的循环前缀,不需要其他辅助数据或者插入导频,可以方便地应用于现有OFDM系统中.

关键词：移动通信正交频分复用多普勒频移自相关

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正交频分复用系统中新的载波精同步算法

上海交通大学学报 2004年第5期38卷 681-683,687页

作者：司源宋文涛罗汉文蔡觉平上海交通大学电子工程系上海200030

提出了一种利用正交频分复用(OFDM)系统的小区广播信道来进行载波同步的算法,减少了OFDM系统的导频所占用的资源,提高了系统的传输效率.仿真结果表明,该算法在加性高斯白噪声信道以及衰落信道下都具有较好的性能.

关键词：正交频分复用小区广播信道载波同步

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软化方法对食用槟榔品质的影响

食品与机械 2017年第7期33卷 189-193页

作者：赵志友巢雨舟袁思颂柳毅肖东夏延斌湖南宾之郎食品科技有限公司工程技术研究中心湖南湘潭411201 湘潭市食用槟榔工程技术研究中心湖南湘潭411201 湖南省槟榔产业技术创新战略联盟理事长单位湖南湘潭411201 湖南农业大学食品科学技术学院湖南长沙410128

采用煮、蒸、碱、酸、微波、酶和反复冷冻7种方法软化槟榔,以未软化的样品为对照,研究软化方法对食用槟榔的咀嚼性、碎渣性、槟榔碱含量、TPA(质构分析)测试、五针穿刺测试和味觉指标的影响。结果表明:蒸(88.1分)、碱(85.3分)和微波(83.... 详细信息

采用煮、蒸、碱、酸、微波、酶和反复冷冻7种方法软化槟榔,以未软化的样品为对照,研究软化方法对食用槟榔的咀嚼性、碎渣性、槟榔碱含量、TPA(质构分析)测试、五针穿刺测试和味觉指标的影响。结果表明:蒸(88.1分)、碱(85.3分)和微波(83.2分)的咀嚼性得分最高;对照(84.7分)、煮(80.7分)和冷冻(78.8分)的碎渣性得分最高;对照(4.90%)、冷冻(4.49%)、碱(4.17%)和酸(4.14%)的槟榔碱含量较高;从TPA测试结果看,酶、微波、蒸和碱的软化效果最好;从五针穿刺测试结果看,微波、碱、酸、酶和蒸的软化效果最好;从味觉指标分析看,煮和蒸可以去酸、苦、涩,但是会降低鲜味,微波和冷冻对风味几乎没影响,碱可以去酸、增咸和增鲜,但是会带来苦和涩,酸会给槟榔带来酸和苦,酶对去酸和涩有轻微作用。综合来看,蒸、微波、酶和碱处理具有软化效果显著、对风味影响较小等特点,更适合应用于实际生产。

关键词：食用槟榔软化咀嚼性槟榔碱

综合ICU导管相关性血流感染流行病学及病原学分析

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中华医院感染学杂志 2017年第12期27卷 2672-2675页

作者：邵小青茅一萍谭思源宋华宁郑伟徐州医科大学护理学院江苏徐州221004 徐州医科大学附属医院感染管理科江苏徐州221000 盐城市第一人民医院感染管理科江苏盐城224000 徐州市第一人民医院感染管理科江苏徐州221000

目的调查徐州地区综合重症监护病房(ICU)导管相关性血流感染(CRBsi)的流行病学和病原学相关情况,分析其变化趋势和特征,为防控工作提供依据。方法对2010年-2014年徐州市23家医院ICU留置中心静脉导管(CL)的患者相关情况进行调查,并对其发... 详细信息

目的调查徐州地区综合重症监护病房(ICU)导管相关性血流感染(CRBsi)的流行病学和病原学相关情况,分析其变化趋势和特征,为防控工作提供依据。方法对2010年-2014年徐州市23家医院ICU留置中心静脉导管(CL)的患者相关情况进行调查,并对其发生CRBsi的流行病学特征、相关危险因素及病原菌分布情况等进行统计分析。结果本研究共纳入4036例CL置管的患者,总CL使用率为43.27%,CRBsi千日感染率为2.05‰。CRBsi的发生与年龄、性别、插管者、置管地点、置管部位和导管腔数等因素之间均存在相关性(Psi患者血培养中共检出261株病原菌,其中革兰阳性菌116株(44.44%),革兰阴性菌125株(47.89%),真菌20株(7.66%),检出耐药菌株为52株(19.92%)。结论 ICU的CRBsi感染率与多种因素密切相关,且耐药菌株检出率的增高,应根据CRBsi监测过程中出现的重点问题制定有效的防控措施,向CRBsi的"零容忍"目标努力。

关键词：重症监护病房导管相关性血流感染流行病学危险因素病原学