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Volume expansion rates of seismic landslides and influencing factors: A case study of the 2008 Wenchuan earthquake

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Journal of Mountain Science 2019年第8期16卷 1731-1742页

作者： MA si-yuan XU Chong XU Xi-wei Key Laboratory of Active Tectonics and Volcano Institute of GeologyChina Earthquake AdministrationBeijing 100029China Institute of Crustal Dynamics China Earthquake AdministrationBeijing 100085China

When a big landside occurs, source material can change into loose deposit during its runout, causing the increase of the total landslide volume to some extent. Such changes can influence the quantification of seismic landslides. The objective of this paper was to study the volume expansion rate of landslides based on the data of 1417 co-seismic landslides triggered by the 2008 Wenchuan, China Mw 7.9 earthquake. We also analyzed the correlations between this rate and landslide geometric parameters(volume, height(H), length-width ratio(L/W), length-height ratio(L/H)), and environmental factors(peak ground acceleration(PGA), lithology, slope angle and aspect). The results show that the total source volume of the 1417 landslides is 1248 million m3, while the total volume of the deposit is 1501 million m3, which means the total volume expanding rate(Et) is 20.3% with the average volume expansion rate(Ea) 22.6%. The analysis indicates that volume expansion rate generally decreases with the increasing volume and height of landslides, while becoming larger with increasing L/H and L/W. Besides, the volume expansion rate is closely related to the landslide type and the volume scale of landslides. This study analyses volume change of co-seismic landslides deeply, permitting to help the correct quantification of the source volume and deposit volume of seismic landslide and a useful reference for the correct quantification of landslide volume.

关键词： Landslide volume Volume expansion rate Wenchuan earthquake Influencing factors

Formation Mechanism of Beach Rocks and Its Controlling Factors in Coral Reef Area, Qilian Islets and Cays,Xisha Islands, China

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Journal of Earth Science 2019年第4期30卷 728-738页

作者： na Zhao Dishu Shen Jian-wei Shen CAS Key L aboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China University of Chinese Academy of Sciences Beijing 100049China Huxi Higher Education Mega Center Chongqing City Management CollegeChongqing 401331China

Beach rock,which forms at the intertidal zone,is a natural barrier to protect beach and island from wave erosion. The formation mechanism of beach rocks is significant in the study of surface carbonate diagenesis and protection of island. Beach rocks in Qilian Islets and Cays were formed about 500–700 a BP,neither its composition nor sedimentary structure experienced intense *** rocks in Qilian Islets and Cays are mainly composed of reef-building skeletal fragments and bioclasts without terrigenous sediments. This study focused on the types and morphologies of cements in beach rocks of Qilian Islets and Cays,and its cementation mechanisms and influencing factors. Biological activities,such as micritization caused by microbial activities and algae binding action,play an important role in the initial stage of bioclast transformation and promote the subsequent early marine and early meteoric cementation. Acicular aragonite induced by early marine cementation is well developed in beach rocks,especially in those samples from Medium Islet. Early meteoric cementation is not common as marine cementation,generally presenting granular and meniscus cements. The main factors affecting the formation and development of beach rocks in Qilian Islets and Cays include sediment source,hydrodynamic condition,climate,sea level change and anthropogenic impacts.

关键词： beach rock cementation micritization coral reef Qilian Islets and Cays the South China Sea

Ion specificity in naCl solution confined in silicon nanochannels

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Science China(Technological Sciences) 2014年第1期57卷 230-238页

作者： QIU YingHua TAN QiYan si wei CHEN YunFei School of Mechanical Engineering and Jiangsu Key Laboratory for Design and Manufacture of Micro-nano Biomedical Instruments Southeast University

Ion specificity of na＋ and C1- ions for naCI solution confined in silicon nanochannels is investigated with molecular dynamics （MD） simulations. The MD simulation results demonstrate that ion specificity for na＋ and C1- ions exhibits clearly in na- nochannels with high surface charge density. The two types of ions show different density distributions perpendicular to the channel surface due to the ion specificity when they act as countefions near negatively and positively charged surfaces, respec- tively. Both the two counterion distributions cannot be predicted by Poisson-Boltzmann equation within 0.75 nm near the sur- face. In addition, the ion specificity is also demonstrated through affecting the water density distributions. In the nanochannel with negatively charged surfaces, the presence of the na＋ ions reduces the number of water peaks in water density distribution profile. In comparison, when the C1- ions act as counterions near positively charged surfaces, they do not affect the number of the water peaks. Besides the influence on the water density distribution, ion specificity also exhibits through affecting the wa- ter molecule orientation in the adsorbed layer. It is found that C1- ions make the water molecules in the adsorbed layer align more orderly than na~ ions do when the two types of ions act as the counterions near the positively and negatively charged surfaces with the same surface charge density.

关键词： ion specificity molecular dynamics simulations nanochannel Poisson-Boltzmann equation electrical double layer

Recent advances in the application of sulfinic acids for the construction of sulfur-containing compounds

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Chinese Chemical Letters 2022年第1期33卷 97-114页

作者： Yufen Lv Huanhuan Cui na Meng Huilan Yue wei wei School of Chemistry and Chemical Engineering Qufu Normal UniversityQufu 273165China Qinghai Provincial Key Laboratory of Tibetan Medicine Research and CAS Key Laboratory of Tibetan Medicine Research Northwest Institute of Plateau BiologyXining 810008China School of Chemistry and Chemical Engineering Shihezi UniversityShihezi 832000China

Sulfur-containing organic compounds display wide applications in the field of materials science,synthetic chemistry,and pharmaceutical ***,numerous synthetic strategies have been developed for the synthesis of sulfur-containing compounds in synthetic *** recent years,the utilization of sulfinic acids as versatile synthons has emerged as attractive and powerful approach to access various organosulfur compounds through sulfonylation,sulfinylation or sulfenylation *** this review,we summarized the recent progress in the construction of various sulfur-containing compounds from sulfininc *** examples of substrates and the related reaction mechanisms are described *** review intends to provide readers a comprehensive understanding on the synthesis of sulfur-containing molecules from sulfinic acids and provide help for future synthetic research.

关键词： Sulfur-containing compounds Sulfinic acids Sulfonylation Sulfinylation Sulfenylation

simulation of landslide run-out by considering frictional heating and thermal pressurization

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Journal of Mountain Science 2019年第1期16卷 122-137页

作者： LIU wei HE si-ming HE Zi-lu Key Laboratory of Mountain Hazards and Surface Process Chinese Academy of Science Institute of Mountain Hazards and Environment Chinese Academy of Sciences CAS Center for Excellence in Tibetan Plateau Earth Sciences Department of Applied Mechanics and Engineering Southwest Jiaotong University

Some of the remarkable characteristics of natural landslides, such as surprisingly long travel distances and high velocities, have been attributed to the mechanisms of frictional heating and thermal pressurization. In this work, this mechanism is combined with a depth-averaged model to simulate the long runout of landslides in the condition of deformation. Some important factors that influence frictional heating and thermal pressurization within the shear zone are further considered, including velocity profile and pressurization coefficient. In order to solve the coupled equations, a combined computational method based on the finite volume method and quadratic upwind interpolation for convective kinematics scheme is proposed. Several numerical tests are performed to demonstrate the feasibility of the computational scheme, the influence of thermal pressurization on landslide run-out, and the potential of the model to simulate an actual landslide.

关键词： Landslide Frictional heating Thermal pressurization Numerical simulation

Realization of a Quantum Scheduling Algorithm Using Nuclear Magnetic Resonance

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Chinese Physics Letters 2004年第7期21卷 1198-1200页

作者： ZHANGJing-Fu DENGZhi-wei PANYan-na LUZhi-Heng DepartmentofPhysics BeijingNormalUniversityBeijing100875 TestingandAnalyticalCenter BeijingNormalUniversityBeijing100875

The quantum scheduling algorithm proposed by Grover is generalized to extend its scope of applications. The generalized algorithm proposed here is realized on a nuclear magnetic resonance quantum computer. The experimental results show that the generalized algorithm can work efficiently in the case that Grover"s scheduling algorithm is completely invalid, and represent the quantum advantages when qubits replace classical bits.

关键词： Computational physics Instrumentation and measurement Quantum information and quantum mechanics

Learning adaptive receptive fields for deep image parsing networks

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Computational Visual Media 2018年第3期4卷 231-244页

作者： Zhen wei Yao Sun Junyu Lin si Liu State Key Laboratory of Information Security Institute of Information Engineering Chinese Academy of Sciences Beijing 100093 China. University of Chinese Academy of Sciences Beijing101408 China. Institute of Information Engineering Chinese Academy of Sciences Beijing 100093 China Key Laboratory of Intelligent Perception and Systems for High-Dimensional Information of Ministry of Education Nanjing University of Science and Technology Nanjing 210094 China.

In this paper,we introduce a novel approach to automatically regulate receptive fields in deep image parsing *** previous work which placed much importance on obtaining better receptive fields using manually selected dilated convolutional kernels,our approach uses two affine transformation layers in the network’s backbone and operates on feature *** maps are inflated or shrunk by the new layer,thereby changing the receptive fields in the following *** use of end-to-end training,the whole framework is data-driven,without laborious manual *** proposed method is generic across datasets and different *** have conducted extensive experiments on both general image parsing tasks,and face parsing tasks as concrete examples,to demonstrate the method’s superior ability to regulate over manual designs.

关键词： semantic segmentation receptive field data-driven face parsing

The impact of Internet access on household dietary quality:Evidence from rural China

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Journal of Integrative Agriculture 2024年第2期23卷 374-383页

作者： Yi Cui Qiran Zhao Thomas Glauben wei si College of Economics and Management China Agricultural UniversityBeijing 100083China Academy of Global Food Economics and Policy China Agricultural UniversityBeijing 100083China Leibniz Institute of Agricultural Development in Transition Economies(IAMO) Halle(Saale)06120Germany

Over the past few decades,the Internet has rapidly diffused across *** spread of the Internet has had a profound economic and social impact on Chinese rural *** research shows that Internet access significantly impacts agricultural production and improves smallholder farmers’*** these,the Internet can affect other dimensions of social ***,research about the impact of Internet access on dietary quality in rural China remains *** study utilizes multi-period panel data from Fixed Observation Point in rural China from 2009 to 2015 to estimate the impact of Internet access on dietary quality and food consumption of rural households and conducts a causal *** models with time and household fixed effects allow robust estimation while reducing potential issues of unobserved *** estimates show that Internet access has significantly increased rural household dietary quality(measured by the Chinese Diet Balance Index).Further research finds that Internet access has increased the consumption of animal products,such as aquatic and dairy *** also examine the underlying *** access improves dietary quality and food consumption mainly through increasing household income and food *** results encourage the promotion of Internet access as a valuable tool for nutritional improvements,especially in rural areas.

关键词： dietary quality fixed effect model Internet access rural China

Magnetic properties of bilayer nano-stanenelike structure with Ruderman-Kittel-Kasuya-Yoshida coupling

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Communications in Theoretical Physics 2022年第6期74卷 168-178页

作者： Xin Su nan si wei Jiang wei-Chun Gao Feng-Ge Zhang School of Environmental and Chemical Engineering Shenyang University of TechnologyShenyang 110870China School of Electric Engineering Shenyang University of TechnologyShenyang 110870China

A bilayer nano-stanene-like structure with Ruderman-Kittel-Kasuya-Yoshida(RKKY)coupling described by the Ising model is proposed. The magnetic and thermodynamic properties are studied using the effective-field theory with correlations. The exchange coupling,longitudinal magnetic field, number of non-magnetic layers, and anisotropies had major influences on the magnetization, specific heat, and internal energy. Different saturation magnetizations are observed on the magnetization curve. The variation in the system blocking temperature is studied. The results provide theoretical guidance for the magnetic investigation of nanomaterials with RKKY coupling.

关键词： bilayer nano-stanene-like structure mixed spin Ising model magnetization internal energy