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Early Age Properties of Cementitious Materials by Electrical Resistivity Measurement

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Journal of wuhan university of technology(Materials science) 2010年第4期25卷 641-644页

作者：魏小胜 School of Civil Engineering and mechanics Huazhong University of Science and Technology

Three cement pastes were prepared with the fixed water-binder ratio and different fly ash contents. The compression test and electrical resistivity measurement of the paste mixes were conducted during 48 h. The changes of the CH content and the non-evaporable water content in the cement-fly ash hydration systems with time were obtained by the thermal gravimetric analysis. The experimental results show that dilution effect of fly ash as micro-filler is dominant mechanism before 48 h, which appears to decrease in the CH content and the non-evaporable water content, also in compressive strength and electrical resistivity, with the increase of fly ash replacement. The relationships between CH content, non-evaporable water content and electrical resistivity show that electrical resistivity can be the indicators of hydration products CH and non-evaporable water. The correlation of the compressive strength fc and the electrical resistivity ρcan be obtained as fc=8.3429ρ=6.7088 for the period of 48 h. The early age compressive strength can then be predicted by electrical resistivity measurement.

关键词： electrical resistivity fly ash compressive strength hydration

Sea level variations in the South China Sea inferred from satellite gravity,altimetry,and oceanographic data

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science China Earth sciences 2012年第10期55卷 1696-1701页

作者： FENG Wei 1,2,zhong Min 1,3 & XU HouZe 1,3 1 State Key Laboratory of Geodesy and Earth’s Dynamics,Institute of Geodesy and Geophysics,Chinese Academy of sciences,wuhan 430077,China 2 Graduate university of Chinese Academy of sciences,Beijing 100049,China 3 Institute of Geophysics,huazhong university of science and technology,wuhan 430074,China State Key Laboratory of Geodesy and Earth’s Dynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China Graduate university of Chinese Academy of sciences Beijing China Institute of Geophysics Huazhong University of Science and Technology Wuhan China

Sea level variations(SLVs) can be divided into two major components:the steric SLV and the mass-induced *** two components of SLV in the South China Sea(SCS) are studied by using satellite altimetry,GRACE(Gravity Recovery and Climate Experiment) satellite gravity,and oceanographic data on annual and inter-annual *** the annual timescale,the geographic distribution of mass-induced SLV's amplitude jointly estimated from altimetry and the ECCO(Estimation of the Circulation and Climate of the Ocean) model agrees very well with that from *** observes obvious seasonal mass-induced SLV in the SCS with annual amplitude of 2.7±0.4 cm,which is consistent with the annual amplitude of 2.7±0.3 cm estimated from the steric-corrected *** the inter-annual timescales,the mean SLV in the SCS shows a large oscillation,which is mainly caused by the steric *** trend of mean SLV inferred from altimetry in the SCS is 5.5±0.7 mm/yr for the period of 1993-2009,which is significantly higher than the global sea level rise rate of 3.3±0.4 mm/yr in the same *** is no obvious trend signal in the mass-induced SLV detected from GRACE that indicates the water exchange between the SCS and its adjacent seas and land is in balance within the study period.

关键词： altimetry GRACE ECCO the South China Sea sea level variation

A toy model for magnetized neutrino-dominated accretion flows

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science China(Physics,mechanics & Astronomy) 2010年第S1期53卷 98-101页

作者： LEI WeiHua,WANG DingXiong,ZHANG Lei,GAN ZhaoMing & ZOU YuanChuan School of Physics,huazhong university of science and technology,wuhan 430074,China School of Physics Huazhong University of Science and Technology Wuhan China

In this paper,we present a simplified model for a magnetized neutrino-dominated accretion flow(NDAF) in which the effect of black hole(BH) spin is taken into account by adopting a set of relativistic correction factors,and the magnetic field is parameterized as β,the ratio of the magnetic pressure to the total *** is found that the disc properties are sensitive to the values of the BH spin and β,and more energy can be extracted from NDAFs by using a faster spin and lower β.

关键词： black hole gamma-ray bursts accretion disc magnetic field

Long-range asymmetric Cherenkov radiation

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science China(Physics,mechanics & Astronomy) 2024年第4期67卷 170-171页

作者： Gang zhong Qingdong Ou Macao Institute of Materials science and Engineering(MIMSE) Faculty of Innovation EngineeringMacao University of Science and TechnologyTaipaMacao 999078China

Cherenkov radiation(CR)is gaining increasing attention as a high-output power Terahertz radiation source,and it plays a significant role in particle detectors,accelerators,and space science[1].This captivating phenomenon was first observed by Cerenkov in 1934 and was later explained theoretically by Tamm and Frank in 1937,earning them the Nobel Prize in Physics in *** occurs when charged particles move faster than the phase velocity of light in a specific medium.

关键词： asymmetric faster explained

Computational Comminution and Its Key Technologies Applied to Materials Processing Procedure

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Journal of wuhan university of technology(Materials science) 2001年第2期16卷 63-68页

作者：黎水平 School of mechanics and Electronics Wuhan University of Technology Wuhan 430070 China

A new concept named computational comminution is proposed in thispaper, which is different from the traditional studies on materialsprocessing procedure such as the study based on theoretic models, thestudy based on experiment models, which is based on informationmodels. Some key technologies applied to mate- rials processingprocedure such as artificial neural networks, fuzzy sets, geneticalgorithms and visualization techn- ology are also presented, and afusing methodology of these new technologies is studied. Applicationin the cement grinding process of Horomill shows that results in thispaper are efficient.

关键词： materials processing computatonal comminution information technology

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具有粘弹性支撑的平板上势流的稳定性

水动力学研究与进展（A辑） 2002年第2期17卷 197-203页

作者：赵汉中华中科技大学力学系湖北武汉430074

本文研究了具有粘弹性支撑的平板上均匀势流中的稳定性问题。在研究中采用基于空间—时间稳定性理论的映射法去搜寻绝对不稳定特征模态。研究结果表明 ,当支撑刚度足够小时总是会有不稳定发生。对于纯弹性支撑 ,尽管有不稳定 ,但它并不... 详细信息

本文研究了具有粘弹性支撑的平板上均匀势流中的稳定性问题。在研究中采用基于空间—时间稳定性理论的映射法去搜寻绝对不稳定特征模态。研究结果表明 ,当支撑刚度足够小时总是会有不稳定发生。对于纯弹性支撑 ,尽管有不稳定 ,但它并不是绝对不稳定 ;而对于粘弹性支撑。

关键词：粘弹性支撑绝对不确定均匀势流稳定性理论映射法

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柔性壁对湍流边界层速度型的变形影响

水动力学研究与进展（A辑） 2002年第4期17卷 391-399页

作者：赵汉中华中科技大学力学系湖北武汉430074

本文从稳定性的观点出发 ,研究了粘弹性柔性壁对湍流边界层的影响。由柔性壁边界层稳定性问题的特征值计算结果发现 ,原刚性壁湍流边界层的速度型导致流固耦合系统不稳定 ,对数区上移后的边界层速度型却可以使耦合系统稳定。这说明 ,在... 详细信息

本文从稳定性的观点出发 ,研究了粘弹性柔性壁对湍流边界层的影响。由柔性壁边界层稳定性问题的特征值计算结果发现 ,原刚性壁湍流边界层的速度型导致流固耦合系统不稳定 ,对数区上移后的边界层速度型却可以使耦合系统稳定。这说明 ,在没有水动力学不稳定发生的情况下。

关键词：湍流边界层柔性壁稳定性速度型

MEASUREMENT OF K_(IC)OF MEDIAN OR LOW STRENGTH STEEL USING ROUND BARS WITH CIRCUMFERENCIAL CRACK

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Acta Metallurgica Sinica(English Letters) 1989年第3期2卷 201-207页

作者： LIU Zaihua huazhong university of science and technology,wuhan,China ZHAO Dongli Bureau of Complete Sets of Equipment,State Machinery Commission,Beijing,China Dept.of mechanics,huazhong university of science and technology,Yujiashan,wuhan,China

The size effect of tension round bars with circumferential crack was described and used to measure the plane-strain fracture toughness K_(1c) of median or low strength *** size of cylindrical specimen required for K_(1c) measurement is much smaller than that of standard *** J-integral values of the cylindrical sqecimens were calculated to characterize the size *** finite element calculution and fracture morphology analysis have been conducted to eyplain the fact that smaller cylindrical specimen could be used to measure K_(1c) of median or low strength steel.

关键词： median or low strength steel fracture touglmess round bar specimen

Recent progress in self-propelled particles

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Journal of Hydrodynamics 2024年第1期36卷 61-77页

作者： Zhen-yu Ouyang Jian-zhong Lin Laboratory of Impact and Safety Engineering Ministry of EducationNingbo UniversityNingbo315201China department of mechanics State Key Laboratory of Fluid Power and Mechatronic SystemsZhejiang UniversityHangzhou310027China

Self-propelled particles are commonly found in a large number of planktonic organisms such as bacteria,fungi,and algae in nature,and researchers have taken a long interest in exploring their swimming mechanisms for more than a *** in the past 20 years,with the development of computational fluid dynamics and flow display technology,as well as the need for the design of synthetic self-propelled particles and micro-swimming devices,self-propelled particles have become the forefront and hotspot of current research in the field of fluid *** paper first introduces the swimming characteristics of common self-propelled particles,leading to a classic“squirmer”type self-propelled particle *** this basis,a systematic introduction and summary of the theoretical and numerical simulation research of“squirmer”will be ***,the main challenges and opportunities faced by the current research will be summarized.

关键词： Self-propelled particles multiphase flow hydrodynamic interaction