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Dynamic Response of Foundations during Startup of High-Frequency Tunnel Equipment

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 821-844页

作者： Dawei Ruan Mingwei hu College of Civil and Transportation Engineering Shenzhen UniversityShenzhen518060China State Key Laboratory of Intelligent Geotechnics and Tunnelling Shenzhen UniversityShenzhen518060China Key Laboratory of Coastal Urban Resilient Infrastructures of Ministry of Education Shenzhen UniversityShenzhen518060China Underground Polis Academy Shenzhen UniversityShenzhen518060China Shenzhen Key Laboratory of Green Efficient and Intelligent Construction of Underground Metro StationShenzhen UniversityShenzhen518060China

The specialized equipment utilized in long-line tunnel engineering is evolving towards large-scale,multifunctional,and complex *** vibration caused by the high-frequency units during regular operation is supported by the foundation of the units,and the magnitude of vibration and the operating frequency fluctuate in different engineering contexts,leading to variations in the dynamic response of the *** high-frequency units yield significantly diverse outcomes under different startup conditions and times,resulting in failure to meet operational requirements,influencing the normal function of the tunnel,and causing harm to the foundation structure,personnel,and property in severe *** article formulates a finite element numerical computation model for solid elements using three-dimensional elastic body theory and integrates field measurements to substantiate and ascertain the crucial parameter configurations of the finite element *** proposing a comprehensive startup timing function for high-frequency dynamic machines under different startup conditions,simulating the frequency andmagnitude variations during the startup process,and suggesting functions for changes in frequency and magnitude,a simulated startup schedule function for high-frequency machines is created through *** into account the selection of the transient dynamic analysis step length,the dynamic response results for the lower dynamic foundation during its fundamental frequency crossing process are *** validation checks if the structural magnitude surpasses the safety threshold during the critical phase of unit startup traversing the structural resonance *** design recommendations for high-frequency units’dynamic foundations are provided,taking into account the startup process of the machine and ensuring the safe operation of the tunnel.

关键词： Tunnel equipment high-frequency units startup conditions transient dynamics dynamic response foundation design

On n-universal quadratic forms over dyadic local fields

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Science China Mathematics 2024年第7期67卷 1481-1506页

作者： Zilong He Yong hu School of Computer Science and Technology Dongguan University of TechnologyDongguan523808China Department of Mathematics Southern University of Science and TechnologyShenzhen518055China

Let n≥2 be an integer. We give necessary and sufficient conditions for an integral quadratic form over dyadic local fields to be n-universal by using invariants from Beli's theory of bases of norm ***, we provide a minimal set for testing n-universal quadratic forms over dyadic local fields, as an analogue of Bhargava and Hanke's 290-theorem(or Conway and Schneeberger's 15-theorem) on universal quadratic forms with integer coefficients.

关键词： integral quadratic forms n-universal quadratic forms dyadic fields 290-theorem

Vortex excites unidirectional water waves near ancient Luoyang Bridge

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Frontiers of physics 2024年第3期19卷 163-165页

作者： Yichen Li Xinhua hu Department of Materials Science and Key Laboratory of Micro-and Nano-Photonic Structures(Ministry of Education) Fudan UniversityShanghai 200433China

Since the discovery of generalized Snell’s law in 2011[1],metasurfaces have opened up the mainstream of arbitrary wavefront manipulation in *** a gradient-index metasurface,the parallel wavenumber kx of reflected wave can be not equal to the incident one(kx=ξ+k0sinθi,where k0 andθi are the incident wavenumber and angle,andξis the phase gradient of metasurface in its supercell)[1].Whenξ>k0,the reflected wave becomes a surface wave bounded on the metasurface(where|kx|>k0,kz is imaginary,and z is normal to the metasurface)[2].However,as research of metasurfaces continually evolves,some articles have pointed out that such graded metasurfaces suffer from a series of problems[3-6].In particular,multiple metallic resonators are adopted in a subwavelength supercell,resulting in impedance mismatch,moderate conversion efficiency,wave absorption,and fabrication ***,although the approach of graded metasurfaces has been demonstrated in the microwave regime,it is hard to extend to infrared and optical ranges with shorter *** solve this problem,Ra’di et al.[7]devised metagratings with periodic arrays of bianisotropic scatterers and showed that they enable wave front engineering with unitary efficiency and significantly lower fabrication demands.

关键词： graded reflected imaginary

黄芪注射液联合噻托溴铵对COPD稳定期患者疗效观察

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国际医药卫生导报 2017年第5期23卷 704-707页

作者：胡海英漯河市中心医院呼吸内科 462000

目的探讨黄芪注射液联合噻托溴铵对COPD稳定期患者疗效观察。方法将COPD稳定期患者70例随机分为研究组与对照组，每组35例。研究组采用黄芪注射液联合噻托溴铵治疗，对照组仅采用噻托溴铵治疗。两组患者均以8周为治疗疗程。结果两组治... 详细信息

目的探讨黄芪注射液联合噻托溴铵对COPD稳定期患者疗效观察。方法将COPD稳定期患者70例随机分为研究组与对照组，每组35例。研究组采用黄芪注射液联合噻托溴铵治疗，对照组仅采用噻托溴铵治疗。两组患者均以8周为治疗疗程。结果两组治疗总有效率对比差异有统计学意义（P〈0．05）；两组患者治疗8周咳嗽和喘促积分均较治疗前显著降低，差异均有统计学意义（均P〈0．05）；治疗8周时研究组患者咳嗽和喘促积分均低于对照组，差异均有统计学意义（均P〈0．05）；两组患者治疗8周PEF、FEV1、FEV1／FVC较治疗前均显著降低，差异均有统计学意义（均P〈0．05）；治疗8周时研究组患者PEF、FEV1、FEV1／FVC均低于对照组，差异均有统计学意义（均P〈0．05）；两组患者治疗8周IL-8、IL-17、IL-18较治疗前均显著降低，差异均有统计学意义（均P〈0．05）；治疗8周时研究组患者IL-8、IL-17、IL-18均低于对照组，差异均有统计学意义（均P〈0．05）；两组用药8周期间均未发生明显药物不良反应。结论黄芪注射液联合噻托溴铵对COPD稳定期患者疗效显著，能够改善患者肺功能和降低炎症因子IL-8、IL-17、IL-18表达。

关键词：黄芪注射液噻托溴铵 COPD稳定期疗效肺功能炎症因子

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中美两国图书馆服务比较研究

情报探索 2013年第5期 107-109页

作者：胡海鹰河南省图书馆河南郑州450052

介绍了以传播、教育、公益为核心的美国图书馆服务精神的内涵,通过中美图书馆网络信息服务比较、知识讲座服务比较、弱势群体服务比较,分析了中美图书馆服务在发挥传播职能、教育职能与公益职能3个方面存在的差距,旨在启迪我国图书馆服... 详细信息

介绍了以传播、教育、公益为核心的美国图书馆服务精神的内涵,通过中美图书馆网络信息服务比较、知识讲座服务比较、弱势群体服务比较,分析了中美图书馆服务在发挥传播职能、教育职能与公益职能3个方面存在的差距,旨在启迪我国图书馆服务建设的新思路。

关键词：中美图书馆讲座服务信息服务弱势群体

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数字图书馆用户关系管理与个性化服务研究

情报探索 2013年第12期 122-124页

作者：胡海鹰河南省图书馆河南郑州450052

从数字图书馆用户关系管理的意义出发,分析了数字图书馆用户关系管理研究的主要内容,提出了改善数字图书馆用户关系管理与个性化服务的关键举措。

关键词：用户关系管理图书馆个性化数字化

Stable, efficient inverted perovskite solar cells enabled by the multifunctional ytterbium oxide buffer

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Science China Chemistry 2024年第8期67卷 2423-2424页

作者： Manman hu Sang Il Seok Department of Energy and Chemical Engineering Ulsan National Institute of Science and TechnologyUlsan 44919Republic of Korea

Significant advancements in single-junction inverted perovskite solar cells (PSCs) have led to power conversion efficiencies (PCEs) exceeding 25% [1]. However, their operational stability under strict conditions falls short compared with commercial solar panels, primarily due to the ion migration. This migration alters the chemical composition within the perovskite layer, increasing the heterogeneity and forming degradation sites [2]. Additionally, ion accumulation at metal interfaces corrodes electrodes, while metal diffusion into perovskite layers further compromises the stability, highlighting critical areas for the improvement in long-term device performance [3,4].

关键词： perovskite exceeding stability

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旅游酒店室内空间文化性设计初探

家具与室内装饰 2013年第5期20卷 42-43页

作者：胡海英中南林业科技大学家具与艺术设计学院湖南长沙410004

旅游酒店空间的文化性设计主要通过承袭性、地域性、民族性等来体现,以使游客在旅游酒店空间中对当地的建筑特色、民俗风情等都有所感悟,来满足人们对在物质和精神生活方面的需要。

关键词：旅游酒店室内空间文化性设计

Removal of pathogenic indicator microorganisms during partial nitrification:the role of free nitrous acid

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 93-102页

作者： Jiaojiao Xu Xiaotian Chen Rui Tang Jingwei Feng Shoujun Yuan Wei Wang Zhen-hu hu Anhui Engineering Laboratory of Rural Water Environment and Resource School of Civil EngineeringHefei University of TechnologyHefei 230009China Hefei 168 High School Hefei 230025China Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power Shanghai University of Electric PowerShanghai 200090China

Digested wastewater contains pathogenic microorganisms and high ammonia concentrations,which can pose a potential risk to public *** removal of pathogens and nitrogen is crucial for the post-treatment of digested *** nitrification-anammox is an energy-saving nitrogen removal *** nitrous acid(FNA),an intermediate product of partial nitrification,has the potential to inactivate ***,the efficiency and mechanisms of FNA-related inactivation in pathogens during partial nitrification remains *** this study,Enterococcus and Escherichia coli(***)were selected to investigate the efficiency and mechanisms of FNA-related inactivation in partial nitrification *** results revealed that 83%±13%and 59%±27%of *** and Enterococcus were removed,respectively,in partial nitrification process at FNA concentrations of 0.023−0.028 mg/*** the concentration of FNA increased from 0 to 0.5 mg/L,the inactivation efficiencies of *** and Enterococcus increased from 0 to 99.9%and 89.9%,*** exhibited a higher resistance to FNA attack compared to ***.3D-laser scanning microscopy(3D-LSM)and scanning electron microscopy(SEM)revealed that FNA exposure caused the surface collapse of *** and Enterococcus,as well as visible pore formation on the surface of *** cells.4',6-Diamidino-2-phenylindole dihydrochloride n-hydrate(DAPI)/propidium iodide(PI)and biomolecule leakage confirmed that inactivation of *** and Enterococcus occurred due to breakdown of cell walls and cell *** findings indicate that partial nitrification process can be used for the removal of residual pathogenic microorganisms.

关键词： Partial nitrification Free nitrous acid Pathogenic indicator microorganism Inactivation Cell structure