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Seismic hazard prediction using multispectral amplification maps in a complex topographic area: A case study of Qiaozhuang town, Sichuan Province, Southwest China

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Journal of Mountain Science 2022年第3期19卷 726-739页

作者： LUO Yong-hong XU qiang ZHAN wei-wei GRELLE Gerardo State Key Laboratory of Geo-Hazard Prevention and Geo-Environment Protection Chengdu University of TechnologyChengdu 610059China Department of Civil and Environmental Engineering Tufts UniversityMedfordMA 02155USA Department of Civil and Environment Engineering University of RomeRome 00184Italy

Earthquakes can cause widely distributed slope failures and damage in mountainous *** accurate prediction of ground motions in mountainous areas is essential for managing the seismic risk of urban cities near mountains but is restricted primarily by complex seismic site amplification effects in areas of uneven *** study selected Qiaozhuang town located in the Qingchuan–Pingwu fault zone,Southwest China,as a case study.A simulator for mapped seismic responses using a hybrid model(Si Se RHMap)was applied to compute the multispectral seismic topographic amplification maps at the three slope units surrounding Qiaozhuang town(weigan hill,***,and ***).Post-earthquake damage survey maps,1 D seismic site response spectral ratios,and H/V spectral ratios of earthquake data were used to validate the computed seismic site amplification factors and resonance *** results suggest that strong topographic amplification effects usually occur at distinct slope locations,such as hilltops,convex slope positions,upslope,and narrow *** computed topographic amplification factors in the study area reached up to 2.4 at upslope or hilltops,and the resonance frequencies were between 3 and 10 *** effects can be as important as stratigraphic effects when assessing seismic amplification effects in the study *** conclude that both topographic and stratigraphic effects should be considered in the comprehensive seismic hazard assessment of the study area or other similar mountain towns.

关键词： Seismic hazard prediction Multispectral amplification map topographic effects Stratigraphic effects SiSeRHMap Wenchuan earthquake

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Shaped charge penetration into high-and ultrahigh-strength Steel-Fiber reactive powder concrete targets

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Defence Technology（防务技术） 2020年第1期16卷 217-224页

作者： qiang-qiang Xiao Zheng-xiang Huang Xudong Zu Xin Jia Qi-feng Zhu wei Cai School of Mechanical Engineering Nanjing University of Science and TechnologyXiaolingwei 200Nanjing210094China China South Industries Group Corporation Chongqing400039China

Experiments on shaped charge penetration into high and ultrahigh strength steel-fiber reactive powder concrete(RPC) targets were performed in this *** show that the variation of penetration depth and crater diameter with concrete strength is different from that of shaped charge penetration into normal strength concrete(NSC).The crater diameter of RPC is smaller than that of NSC penetrated by the shaped *** jet particles are strongly disturbed and hardly reach the crater bottom because they pass through the narrow channel formed by jet penetration into the *** effects of radial drift velocity and gap effects of jet particles for a shaped charge penetration into RFC target are ***,a theoretical model is presented to describe the penetration of shaped charge into RPC *** the concrete strength increases,the penetration resistance increases and the entrance crater diameter *** the drift velocity and narrow crater channel,the low-velocity jet particles can hardly reach the crater bottom to increase the penetration ***,the narrow channel has a stronger interference to the jet particles with increasing concrete strength;hence,the gap effects must be *** drift velocity and gap effects,which are the same as penetration resistance,also have significant effects during the process of shaped charge penetration into ultrahigh-strength concrete,The crater profiles are calculated through a theoretical model,and the results are in good agreement with the experiments.

关键词： Shaped charge Reactive powder concrete target Penetration Radial drift velocity Gap effects

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High Electrical and Thermal Conductivity of Nano-Ag Paste for Power Electronic Applications

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Acta Metallurgica Sinica(English Letters) 2020年第11期33卷 1543-1555页

作者： Hong-qiang Zhang Hai-Lin Bai qiang Jia wei Guo Lei Liu Gui-Sheng Zou School of Mechanical Engineering and Automation.Beihang University Beijing 100191China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China

The nano-Ag paste consisted of Ag nanoparticles and organic *** organics would be removed by evaporation or decomposition during *** the sintering temperature was 300℃,the resistivity of sintered bulk was 8.35×10^-6Ωcm,and its thermal conductivity was 247 W m^-1 K^-*** Si/SiC chips and direct bonding copper(DBC)substrates could be bonded by this nano-Ag paste at low *** bonding interface,sintered microstructure and shear strength of Si/SiC chip attachment were investigated by scanning electron microscopy,transmission electron microscopy and shear *** showed that the sintered Ag layer was porous structure and tightly adhered to the electroless nickel immersion gold surface of DBC substrate and formed the continuous Ag–Au interdiffusion *** shear strength of Si and SiC chip attachments was higher than 35 MPa when the sintering pressure was 10 *** fracture occurred inside the sintered Ag layer,and the fracture surface had obvious plastic deformation.

关键词： Nano-Ag paste Sintering process Interfacial microstructure Chip attachment Shear strength

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Heavy-metal contents in suspended solids of Meiliang Bay,Taihu Lake and its environmental significances

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Journal of Environmental Sciences 2005年第4期17卷 672-675页

作者： ZHUGuang-wei CHIQiao-qiao QINBo-qiang WANGWen-min NanjingInstituteofGeographyandLimnology ChineseAcademyofSciencesNanjing210008China JiangxiAgriculturalUniversity Nanchang330045China NanjingInstituteofGeographyandLimnology ChineseAcademyofSciencesNanjing210008China／／GraduateChina SchoolofChineseAcademyofSciences Beijing100039

Surface water was taken from river mouth to the central area of Meiliang Bay, Taihu Lake, a large shallow eutrophic lake in China. Suspended solids were condensed by centrifugation 25 L surface water samples from each selected site. Suspended solids and surface sediments were further freeze-dried and microwave digested before determining the metals by ICP-AES. Among the metals analyzed in suspended solids and sediments, contents of Cr, Cu, Mn, Ni, and Zn in suspended solids were significantly higher than those in sediments while contents of Al, Ba, Be, Ca, Co, Fe, K, Mg, Pb, and V in suspended solids were 10%—30% higher than those in sediments. Sr and Ti contents in suspended solids and sediments were very similar. Na content in suspended solids was lower than that in sediments. Heavy metals were significantly accumulated in suspended solids. From the river mouth to the center of Meiliang Bay, contents of Cr, Cu, Pb, and Zn in suspended solids showed a gradual decreasing trend indicating the river(Zhihugang River) still discharged large quantity of heavy metals to Meiliang Bay. The study suggests that the geochemical behaviors and ecological effects of heavy metals in suspended solids may serve as a good indicator for the pollution of lake.

关键词： shallow lakes suspended solids heavy metals Taihu Lake

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Tf_2O-TMDS combination for the direct reductive transformation of secondary amides to aldimines,aldehydes, and/or amines

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Science China Chemistry 2016年第12期59卷 1638-1644页

作者： Qi-wei Lang Xiu-Ning Hu Pei-qiang Huang Department of Chemistry Fujian Provincial Key Laboratory of Chemical Biology Collaborative Innovation Center of Chemistry for Energy Materials College of Chemistry and Chemical Engineering Xiamen University

The direct partial reduction of highly stable secondary amides to more reactive aldimines and aldehydes is a challenging yet highly demanding transformation. In this context, only three methods have been reported. We report herein an improved version of the Charette's method. Our protocol consists of activation of secondary amides with triflic anhydride/2-fluoropyridine,and partial reduction of the resulting intermediates with 1,1,3,3-tetramethyldisiloxane(TMDS), which delivered aldimines or aldehydes upon acidic hydrolysis. Aromatic amides were reduced to the corresponding aldimines in 85%–100% NMR yields,and yields(NMR) from aliphatic amides were 72%–86%. Acidic hydrolysis of the aldimine intermediates afforded, in one-pot,the corresponding aldehydes in 80%–96% yields. A simple protocol was established to isolate labile aldimines in pure form in92%–96% yields. The improved method gave generally higher yields as compared to the known ones, and features the use of cheaper and more atom-economical TMDS as a chemoselective reducing agent. In addition, a convenient extraction protocol has been established to allow the isolation of amines, which constitutes a mild method for the N-deacylation of amides, another highly desirable transformation. The extended method retains the advantages of the original method of Charette in terms of mild conditions, good functional group tolerance, and excellent chemoselectivity.

关键词： secondary amides amide activation partial reduction aldimines N-deacylation

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Spatial and temporal variability of turbulent mixing in the near-field of the Changjiang River

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Journal of Oceanology and Limnology 2020年第4期38卷 1138-1152页

作者： WANG Jianfeng YU Fei REN qiang wei Chuanjie CAS Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China

Based on field hydrological,microstructural,and shipboard Acoustic Doppler Current Profiler data,we quantified the spatial and temporal variability of turbulent mixing in the near-field Changjiang(Yangtze)River *** surface dissipation rate(ε)changed by three orders of magnitude from near-field(10^-4 W/kg)to far-field(10^-7 W/kg)plumes,indicating a decrease with distance from the river *** the river plume,εchanged with depth to 10^-8 W/kg,and increased to 10^-6 W/kg at the layer where the Taiwan Warm Current(TWC)***,εin the near-field plume showed three layers:surface layer in the river plume,middle layer,and lower TWC *** the river plume,the strongestεand turbulent diffusivity(Kz)were greater than 10^-4 W/kg and 10^-2 m^2/s,respectively,during strong ebb tides.A three-orders-of-magnitude change inεand Kz was observed in the tidal *** depth of the halocline changed with tidal cycles,and stratification(N 2)varied by one order of *** in the TWC layer followed the distribution of the halocline,which is opposite to the dissipation *** currents led to intrusion and turbulent mixing in the TWC *** ebb tides,εand Kz were as strong as those measured in the river plume,but did not last as *** structure of the velocity shear was similar to the dissipation rate in both the river plume and TWC layer,whereas the velocity shear in the TWC layer did not match the stratification *** the high dissipation rate area,the gradient Richardson number was smaller than the critical value(Ri g<1/4).The Ri g structure was consistent with shear and dissipation distributions,indicating that turbulent mixing in the near-field plume was controlled by a combination of shear induced by the discharged river flow and tidal current.

关键词： Changjiang River near-field plume turbulent mixing observation microstructure

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The primary influence of shear band evolution on the slope bearing capacity

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第4期15卷 1023-1037页

作者： Lanting wei qiang Xu Shanyong Wang Xu Ji Chengdu University of Technology ChengduChina Priority Research Centre for Geotechnical Science and Engineering School of EngineeringUniversity of NewcastleNewcastleAustralia

Slope bearing capacity is one of the most important characteristics in slope engineering and is strongly influenced by weak planes,loading conditions,and slope *** presenting the evolution of slip surfaces,this paper explored how the slope bearing capacity is affected by widely observed influencing *** initiation and propagation of slip surfaces are presented in laboratory model tests of slope using the transparent soil *** band evolution under various weak planes,loading conditions,and slope geometries were experimentally presented,and slope bearing capacities were analyzed with the process of shear band *** paper verified that slip surface morphologies have a strong relation with the slope bearing *** same slip surface morphology can have different evolutionary *** this case,it is the shear band evolution that determines the slope bearing capacity,not the morphology of the slip *** influencing factors such as pre-existing weak planes,loading conditions,and slope geometry strongly affect the slope bearing capacity as these factors govern the process of shear band evolution inside the slope.

关键词： Slope bearing capacity Shear band evolution Failure mechanism Transparent soil

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Raman and infrared spectroscopic quantification of the carbonate concentration in K_(2)CO_(3)aqueous solutions with water as an internal standard

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Geoscience Frontiers 2021年第2期12卷 1018-1030页

作者： Yunlu Ma wei Yan qiang Sun Xi Liu School of Earth and Space Sciences Peking UniversityBeijing 100871China Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education of ChinaBeijing 100871China

Carbonate-bearing fluids widely exist in different geological settings,and play important roles in transporting some elements such as the rare earth *** may be trapped as large or small fluid inclusions(with the size down to<1μm sometimes),and record critical physical-chemical signals for the formations of their host *** methods like Raman spectroscopy and infrared spectroscopy have been proposed as effective methods to quantify the carbonate concentrations of these fluid *** they have some great technical advantages over the conventional microthermometry method,there are still some technical difficulties to overcome before they can be routinely used to solve relevant geological *** typical limitations include their interlaboratory difference and poor performance on micro fluid *** study prepared standard ion-distilled water and K_(2)CO_(3)aqueous solutions at different molarities(from 0.5 to 5.5 mol/L),measured densities,collected Raman and infrared spectra,and explored correlations between the K_(2)CO_(3)molarity and the spectroscopic features at ambient P-T *** result confirms that the Raman O-H stretching mode can be used as an internal standard to determine the carbonate concentrations despite some significant differences among the correlations,established in different laboratories,between the relative Raman intensity of the C-O symmetric stretching mode and that of the O-H stretching *** further reveals that the interlaboratory difference can be readily removed by performing one high-quality calibration experiment,provided that later quantifying analyses are conducted using the same Raman spectrometer with the same analytical *** infrared absorption data were collected from thin fluid films(thickness less than~2μm)formed by pressing the prepared solutions in a Microcompression Cell with two diamond-II *** data show that both the O-H stretching mode and the O-H be

关键词： Carbonate aqueous solution Micro fluid inclusion K_(2)CO_(3)concentration Relative Raman intensity Relative IR absorbance

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Regional Sustainable Assessment at City Level Based on CSDIS(China Sustainable Development Indicator System)Concept in the New Era,China

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Chinese Geographical Science 2020年第6期30卷 976-992页

作者： wei Jianfei DING Zhiwei MENG Yiwei LI qiang Key Laboratory of Geospatial Technology for Middle and Lower Yellow River Regions of Ministry of Education&Collaborative Innovation Center of Urban-Rural Coordinated Development of Henan Province/Key Research Institute of Yellow River Civilization and Sustainable Development&Collaborative Innovation Center on Yellow River Civilization of Henan Province Henan University^Kaifeng 475004China College of Environment and Planning Henan University^Kaifeng 475004China College of Urban Economics and Public Administration Capital University of Economics and BusinessBeijing 100070China

The core issue of sustainable development refers to the coordinated development of economic-social-environmental *** the present study,by complying with the China Sustainable Development Indicator System(CSDIS)concept,a comprehensive index system was built;besides,Natural Breaks(Jenks)Classification Method,Exploratory Spatial Data Analysis and Geographic Detector Analysis were conducted to delve into the sustainability and coordinated degree at city level in China from 2007 to *** achieved results are presented as ***,for spatial differentiation,the overall spatial distribution pattern was characterized by the high-value units in eastern China and the low-value units in western China from 2007 to *** be specific,the high-value units were radiated along the Beijing-Guangdong Axis(Jing-Guang Axis)centered on the core of Beijing-Tianjin-Hebei Region,the middle-value units were distributed in strips along the coast,and the low-value units were vastly gathered in western China and gradually break via the Hu Huanyong line(Hu Line)in south China from 2007 to *** specifically,based on the five subsystems,the pattern of each system was consistent with the whole,whereas the degree of concentration was ***,for spatial correlation,the significant High-High(HH)areas were primarily distributed in the core of Beijing-Tianjin-Hebei,Yangtze River Delta and Pearl River Delta *** significant Low-Low(LL)areas were continuously distributed in the southwest China and broke through the Hu Line from 2007 to *** were insufficient number of significant High-Low(HL)and significant Low-High(LH)areas,whereas the spatial agglomeration of them was less ***,for internal coupling coordination,the spatial differentiation between the coupling degree and the coupling coordinated degree was significantly consistent in 2007 and *** Beijing-Tianjin-Hebei,Yangtze River Delta and Pearl River Delta Regions have demonstrated a high lev

关键词： sustainable development level spatial differentiation city level China

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Design and construction of a multi-sensor position monitoring system applied to key components of synchrotron sources

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Nuclear Science and Techniques 2016年第6期27卷 79-85页

作者： wei Wang Zheng Tang Xiao-Ye He qiang Zhang University of Science and Technology of China Hefei 230029China

High-accuracy position monitoring of key components is required for modern synchrotron sources,such as free-electron lasers and diffraction-limited storage *** various position monitoring sensors have been adopted to monitor the displacement of key components in each direction in real time,these monitoring systems are usually based on their own coordinate *** from such systems are meaningful when evaluating and examining the data from each positioning monitoring system in a unified coordinate *** paper presents the design and construction of a multi-sensor position monitoring system(MPMS).A hydrostatic levelling system,a wire position sensor(WPS) and a tiltmeter are fixed to a stainless steel plate that has been calibrated by a coordinate-measurement *** plates form the *** system must compensate for the sag of the stretched wires so that the WPSs create a straight *** method of the coordinate transformation from the sensor coordinate system to the MPMS coordinate system was thoroughly *** experimental MPMS that includes five plates was setup in a 20-m tunnel,and a validation study to verify fully the feasibility of the MPMS was performed.

关键词：实时监测系统位置传感器自由电子激光器坐标系统坐标变换方法关键部件不锈钢板同步加速器

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