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Source tectonic dynamics features of Jiuzhaigou Ms 7.0 earthquake in Sichuan Province,China

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Journal of Mountain Science 2018年第10期15卷 2266-2275页

作者： YI Shu-jian WU chun-hao LI Yu-sheng HUANG Chao State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China Key Laboratory of Mountain Hazards and Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Science Beijing 100049China

On August 8, 2017, a Ms 7.0 earthquake occurred 5 km to the west of Jiuzhaigou National Park, causing 25 deaths and injuring 525. The objective of this study was to explore the seismogenic fault of the earthquake and tectonic dynamics of the source rupture. Field investigations, radon activity tests, remote sensing interpretations, and geophysical data analyses were carried out immediately after the earthquake. The Jiuzhaigou earthquake occurred at the intersection of the northern margin of the Minshan uplift belt and the south part of the Wenxian–Maqin fault in the south margin of the West Qinling geosyncline. There are two surface rupture zones trending northwest(NW), which are ground coseismic ruptures caused by concealed earthquake faults. The rupture on the southwest is the structure triggering the earthquake, along the Jiuzhaitiantang–Epicenter–Wuhuahai. The other one on the northeast(Shangsizhai–Zhongcha–Bimang) is a reactivation and extension of the secondary fault trending NW. The source rupture of this earthquake is a strike-slipshear fracture associated with the fault plane trending NW 331° and steeply dipping 75°, which is continuously expanding at both ends. The tectonic dynamics process of the source rupture is that the "Jiuzhaigou protrusion" is left-lateral sheared along the seismogenic fault in the NW direction. Finally, the Maqin fault and the arc fault system at the top of the "Wenxian protrusion" will be gradually broken through sometime in far future, as well as earthquaketriggered landslides will be further occurred along the narrow corridor between the seismogenic faults. The research results revealed the basic geological data and tectonic dynamic mechanism in this earthquake.

关键词： Jiuzhaigou Earthquake Surface rupture Tectonic dynamics Radon activity

Comparison of the Stress Corrosion Cracking Behaviour of AISI 304 Pipes Welded by TIG and LBW

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Acta Metallurgica Sinica(English Letters) 2021年第4期34卷 579-589页

作者： Ji-Jin Xu Shuai Wang Ze Chai chun Yu Jun-Mei Chen hao Lu Shanghai Key Laboratory of Materials Laser Processing and Modification School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China

The stress corrosion cracking(SCC)behaviour of AISI 304 pipe girth welds which were welded by a single-pass laser beam welding(LBW)and a multi-pass tungsten inert gas welding(TIG),respectively,was studied by the slow strain rate tests combined with the electrochemical corrosion *** results show that fracture of both the TIG joint and LBW joint occurs in the heat-affected zone(HAZ).According to the electron-backscattered diffraction observation of the micro structures,comparison of potentiodynamic polarization curves and X-ray photoelectron spectroscopy analysis of corrosion products on HAZs of the two joints after the electrochemical tests,the LBW joint exhibits better SCC resistance than the TIG joint in corrosion environments,due to the synthetic effect of more Cr_(2)O_(3) in corrosion products,finer grains,lower residual strain and higher δ-ferrite content in its *** the TIG joint has better mechanical property,considering lower SCC susceptibility and higher production efficiency of the LBW joint,the LBW promisingly replaces the TIG for welding of AISI304 pipes in the nuclear power industry.

关键词： Laser beam welding Slow strain rate test Stress corrosion cracking Tungsten inert gas welding AISI 304 stainless steel

Current Reversals of an Underdamped Brownian Particle in an Asymmetric Deformable Potential

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Communications in Theoretical Physics 2018年第3期69卷 266-270页

作者： chun-chun Cai Jian-Li Liu hao Chen Feng-Guo Li Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials School of Physics and Telecom- munication Engineering South China Normal University Guangzhou 510006 China

Transport of an underdamped Brownian particle in a one-dimensional asymmetric deformable potential is investigated in the presence of both an ac force and a static force,*** numerical simulations,we obtain the current average *** current reversals and the absolute negative mobility are *** increasing of the deformation of the potential can cause the absolute negative mobility to be suppressed and even *** the static force is small,the increase of the potential deformation suppresses the absolute negative *** the force is large,the absolute negative mobility *** particular,when the potential deformation is equal to0.015,the two current reversals present with the increasing of the ***,when the potential deformation is small,there are three current reversals with the increasing of the friction coefficient and the average velocity presents a oscillation behavior.

关键词： particle transport asymmetric deformable potential absolute negative mobility current reversals

Symmetry of Positive Solutions to the Coupled Fractional System with Isolated Singularities

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Acta Mathematica Sinica,English Series 2021年第9期37卷 1437-1452页

作者： Meng Hui LI Jin chun HE hao Yuan XU Mei Hua YANG School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan 430074P.R.China

In this paper,we consider the following two-coupled fractional Laplacian system with two or more isolated singularities(-△)^(s)u=μ1u^(2q+1)+βu^(p1-1)v^(p2)(-△)^(s)v=μ2v(2q+1+βu^p1v^p2-1)in R(n)\Λ,u>0,u>0,where s∈(0,1),n>2s and n≥2.μ1,μ2 andβare all positive constants.p1,p2>1 and p1+p2=2q+2∈((2n-2s)/(n-2s),(2n)/(n-2s)].Λ■R^(n)contains finitely many isolated *** the method of moving plane,we obtain the symmetry results for positive solutions to above system.

关键词： Fractional Laplacian system moving plane symmetry singularity

Effects of rare earth elements on inclusions, microstructure and impact toughness of spring steel

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Journal of Iron and Steel Research International 2024年第4期31卷 933-944页

作者： chun-lei hao Chao-yun Yang Peng Liu Yi-kun Luan Bao-guang Sang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina School of Mechanical Engineering and Automation Dalian Polytechnic UniversityDalian 116034LiaoningChina

Spring steel is an indispensable basic part manufacturing material in mechanical equipment,which is widely used in transportation tools such as automobiles,railways,construction machinery and other *** effects of rare earth(RE)on inclusions,microstructure,carbides and impact toughness of 50CrV spring steel were studied by means of optical microscope,scanning electron microscope,transmission electron microscope and impact *** results show that the addition of rare earth can modify the main MnS and Al_(2)O_(3) inclusions in steel to form spherical or near-spherical rare earth inclusions,and the size of inclusions is significantly *** the quenched structure,the size of martensite slab becomes smaller and the structure is *** tempering,the carbide changes from sheet to ellipse,which makes it easier for spring steel to form stress concentration cracks under *** becomes finer and more dispersed,which leads to better pinning of grain boundaries and smaller grain *** impact toughness of 50CrV-RE spring steel increased from 21 to 41 J by 95%due to the improvement of inclusions,microstructure and carbides by rare *** is possible to improve the strength and toughness of spring steel for the improvement of railway running speed and the development of vehicle lightweight in China.

关键词： Rare earth-Spring steel Inclusion Microstructure Impact toughness

Optical Absorption of Sol-Gel Derived ZnO/TiO_(2) Nanocomposite Films

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Chinese Physics Letters 2001年第11期18卷 1520-1522页

作者： YUAN Zhi-hao TANG Cheng-chun FAN Shou-Shan Department of Chemistry Tsinghua UniversityBeijing 100084 Department of Physics Tsinghua UniversityBeijing 100084

ZnO/TiO_(2) nanocomposite films on quartz substrates were prepared by the sol-gel method, and the corresponding optical absorption properties were investigated. In the ultraviolet region, it was found that the position of fundamental absorption edge partially depends on the composition of the ZnO/TiO_(2 ) films, and shifts toward a shorter wavelength with the increasing content of ZnO in the films. Moreover, a blueshift of the absorption edge resulted from a quantum size effect and the quantum confinement effect was observed in the ZnO/TiO_(2) system.

关键词： composite absorption effect

Polaron and molecular states of a spin-orbit coupled impurity in a spinless Fermi sea

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Chinese Physics B 2021年第10期30卷 447-456页

作者： Hong-hao Yin Tian-Yang Xie An-chun Ji Qing Sun Department of Physics Capital Normal UniversityBeijing 100048China

We investigate the polaron and molecular states of a fermionic atom with one-dimensional spin-orbit coupling(SOC)coupled to a three-dimensional spinless Fermi *** of the interplay among the SOC,Raman coupling and spinselected interatomic interactions,the polaron state induced by the spin-orbit coupled impurity exhibits quite unique *** find that the energy dispersion of the polaron generally has a double-minimum structure,which results in a finite center-of-mass(c.m.)momentum in the ground state,different from the zero-momentum polarons where SOC are introduced into the majority *** further tuning the parameters such as the atomic interaction strength,a discontinuous transition between the polarons with different *** may occur,signaled by the singular behavior of the quasiparticle residue and effective mass of the ***,the molecular state as well as the polaron-to-molecule transition is also strongly affected by the Raman coupling and the effective Zeeman field,which are introduced by the lasers generating SOC on the impurity *** also discuss the effects of a more general spin-dependent interaction and mass *** results would be beneficial for the study of impurity physics brought by SOC.

关键词： spin-orbit coupling polaron Fermi gas

Radical involved reactive wetting and retarding mechanism of alumina refractory ceramic by molten slags under weak static magnetic field

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Journal of Iron and Steel Research International 2024年第6期31卷 1355-1366页

作者： Sheng-hao Li Ao Huang Fan-bo Zeng Hui Peng hao-ran Wei Xue-chun Huang Sheng-qiang Song Hua-zhi Gu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

High alumina slag will cause severe corrosion at the interface of alumina refractory,and the wetting behavior of slag is a key factor influencing the corrosion resistance of refractory *** static magnetic field is a promising solution for improvement in the slag resistance of *** wetting of alumina refractory ceramics with different basicities of high alumina slags under a weak static magnetic field was analyzed,given that a weak static magnetic field can affect the corrosion behavior of refractory *** slag S_(3) as an example,when there was an external static magnetic field of 1.0 mT at 1600 ℃,the thickness of calcium aluminate reaction layer at the interface decreased by 36.7%,the denting depth of interface decreased by 35.6%,and the apparent wetting angle increased by 20%.The living radicals and their formation path in oxide melts were verified by first-principles calculation combined with electron paramagnetic resonance spectroscopy *** influence of the flux density of a weak static magnetic field on the wetting behavior of slags was also *** contact angle of the slags increased owing to the inhibitory effect of magnetic field on the radicalinvolved reaction at the interface of the slag and the alumina refractory *** relationships between the magnetic flux density,diffusion coefficient,slag microstructure(hyperfine coupling constant),and contact angle were *** provides a theoretical basis for the field control of radical involved reactive wetting between inorganic oxide slags and solid oxide ceramics.

关键词： Alumina refractory ceramic Molten slag Weak magnetic field effect Reactive wetting Free radical

Effect of Land Use on Soil Phosphorus Sorption-Desorption Under Intensive Agricultural Practices in Plastic-Film Greenhouses

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Pedosphere 2014年第3期24卷 367-377页

作者： YANG Guang-Rong hao Xi-Ying LI chun-Li LI Yong-Mei Agriculture and Agri-Food Canada Lethbridge Research Centre Yunnan Agricultural University

With rapid urbanization and economic growth, Chinese traditional rice-legume production is increasingly replaced by vegetable and horticultural flower production, which could affect soil properties. This study was conducted near Kunming City, Yunnan Province, Southwest China to investigate how soil phosphorus （P） sorption and desorption processes respond to land use changes and to relate P sorption and desorption parameters to soil properties. Soil samples （0-20, 20-40, 40-60, 60-80 and 80-100 cm） were collected from five sites representing four land use types： rice-legume production in a two-crop, one-year rotation （Rice）, vegetable production in open fields （Vegetable）, recent （〈 3 years） conversion from open fields to plastic-film greenhouse vegetable and flower production at two sites （VFCS1 and VFCS2）, and longer-term （〉 10 years） plastic-film greenhouse vegetable and flower production （VFCL）. The changes in land use affected soil pH, electrical conductivity, available N and P and organic carbon content in topsoil and subsoil. In turn, these changes of soil properties influenced soil P sorption capacity. The P sorption maximum （Smax） was affected by land use types, soil sampling depth and their interactions （P 〈 0.0001）. For surface soil, Smax was in the order of Rice （1 380 mg kg-1）〉 VFCL （1 154 mg kg-1）〉 VFCS2 （897 mg kg-1）〉 VFCS1 （845 mg kg-1）〉 Vegetable （747 mg kg-1）. The lowest Sm^x generally occurred at the surface （except for Rice at 80-100 cm） and increased with depth. The amount of P desorbed during the 8 successive extractions was in the range 23%-44% of sorbed P, and was not affected by land use types or sampling depths. The decreases in Smax suggested that soil P sorption capacity decreased when rice-legume production converted to more intensive vegetation and flower production and caution should be exercised when applying P fertilizer to minimize potential leaching and runoff P loss to the environment.

关键词： flower production P sorption maximum rice-legume production vegetable production