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Chinese Journal of Oceanology and Limnology 2014年第1期32卷 155-161页

作者：程芳晋俞志明宋秀贤 Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of Sciences University of Chinese Academy of Sciences

Long-term data on diatom assemblages in a sediment core(60 cm) obtained from the Changjiang(Yangtze) River estuary were analyzed in order to assess the environmental changes that took place in the approximately 38 years(as determined by 210 Pb measurements), i.e., between 1974 and 2012, of sediment accumulation. From the sediment core, 62 diatom taxa and genera were identifi ed. The diatom biomass in the core generally increased beginning in the mid-1990s(core depth: 35 cm), accompanied by a shift in the dominant species from Podosira stelliger and two species of Cyclotella( C. stylorum and C. striata) to Paralia sulcata, three species of Thalassiosira( T. eccentria, T. oestrupii, and T. excentrica), Actinoptychus undulates, and Thalassionema nitzschioides. The changes in both species diversity and abundance suggested that since the 1980s the estuary has undergone extensive eutrophication. This conclusion was supported by the increased proportion of planktonic species, another indicator of high nutrients inputs, in the Changjiang River estuary.

关键词：沉积硅藻长江口河口长期变化环境影响组合和物种多样性中国

A catastrophic debris flow in the Wenchuan Earthquake area,July 2013：characteristics,formation,and risk reduction

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Journal of Mountain Science 2017年第1期14卷 15-30页

作者： HU Tao HUANG Run-qiu State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China

In the Wenchuan Earthquake area,many co-seismic landslides formed blocking-dams in debris flow channels. This blocking and bursting of landslide dams amplifies the debris flow scale and results in severe catastrophes. The catastrophic debris flow that occurred in Qipan gully(Wenchuan,Southwest china) on July 11,2013 was caused by intense rainfall and upstream cascading bursting of landslide dams. To gain an understanding of the processes of dam bursting and subsequent debris flow scale amplification effect,we attempted to estimate the bursting debris flow peak discharges along the main gully and analyzed the scale amplification process. The results showed that the antecedent and triggering rainfalls for 11 July debris flow event were 88.0 mm and 21.6 mm,respectively. The event highlights the fact that lower rainfall intensity can trigger debris flows after the earthquake. Calculations of the debris flow peak discharge showed that the peak discharges after the dams-bursting were 1.17–1.69 times greater than the upstream peak discharge. The peak discharge at the gully outlet reached 2553 m^3/s which was amplified by 4.76 times in comparison with the initial peak discharge in the upstream. To mitigate debris flow disasters,a new drainage channel with a trapezoidal V-shaped cross section was proposed. The characteristic lengths(h1 and h2) under optimal hydraulic conditions were calculated as 4.50 m and 0.90 m,respectively.

关键词：泥石流沟特征长度地震区灾难汶川洪峰流量风险放大效应

Theoretical framework of dualistic nature–social water cycle

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Chinese Science Bulletin 2014年第4期59卷 810-820页

作者： Dayong Qin Chuiyu Lu Jiahong Liu Hao Wang Jianhua Wang Haihong Li Junyin Chu Genfa Chen State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research

The global climate change and intensification of human activities in recent decades have made profound changes in hydrological cycle processes and water resources,and produced serious water problems and water crisis in many *** main reason is that the driving force of water cycle,the structure of water cycle,and the parameters of water cycle have dualistically evolved under the influence of human activities,and consequently resulted in reduction of runoff water resources,water pollution,and degradation of natural *** order to realize of the safety aim of water supply,water environment,and ecosystem in area which is short of water resources,scientific regulation of water resources must take basin water cycle system as the unified base,and the first scientific basis is the awareness of the internal mechanism and law of water cycle evolution under highly intensive human *** article discussed four aspects of dualistic water cycle evolution,including its history in china,its theory,its characteristics in a typical basin,and its description of integral structure,along with the conceptive model system to quantify *** article can be a reference to the basic cognition of water cycle evolution in a changing environment,and the study of water resources reduction reasons in the contemporary age.

关键词：社会水循环二元论水资源短缺自然生态系统性质框架人类活动全球气候变化

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A computational method for wide-azimuth 3D dip-angle gathers using Gaussian beam migration

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Petroleum Science 2022年第5期19卷 2081-2094页

作者： Su-Bin Zhuang Jian-Ping Huang Ji-Dong Yang Zhen-Chun Li School of Geosciences China University of Petroleum(East China)Qingdao266580ShandongChina

The dip-angle-domain common-image gather(DDCIG)is a key tool to separate the diffraction and reflection imaging *** with different spatial geometries produce different responses in *** with Kirchhoff migration,Gaussian beam migration(GBM)is more effective and robust to overcome the multipathing *** a ray-based method,it has explicit angle information naturally during the *** have developed a 3D DDCIG computational method using GBM,which obtain both the imaging result and angle-domain gathers with only one pass of *** angle-gather computation is based on geometrical optics,and multiple angle conversions are implemented under the rules of space geometry,which helps to avoid rounding errors and improve ***,the multi-azimuth joint presentation strategy is proposed to describe the characteristic of omnidirectional dip angles using a finite number of *** using a 2D model to illustrate application advantages of DDCIG,we apply the proposed method to two 3D models to test its feasibility and accuracy.A field data example further demonstrates the adaptability of our method to seismic imaging for a land survey.

关键词： Gaussian beam Dip-angle gathers 3D imaging Diffraction

Elastic direct envelope inversion based on wave mode decomposition for multi-parameter reconstruction of strong-scattering media

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Petroleum Science 2022年第5期19卷 2046-2063页

作者： Pan Zhang Ru-Shan Wu Li-Guo Han Yong Hu College of Geo-exploration Science and Technology Jilin UniversityChangchun 130026JilinChina Modeling and Imaging Laboratory Earth&Planetary ScienceUniversity of California at Santa CruzSanta CruzCalifornia95064USA School of Resources and Geosciences China University of Mining and TechnologyXuzhou 221008JiangsuChina

The parameter reconstruction of strong-scattering media is a challenge for conventional full waveform inversion(FWI).Direct envelope inversion(DEI)is an effective method for large-scale and strongscattering structures imaging without the need of low-frequency seismic ***,the current DEI methods are all based on the acoustic ***,in real cases,seismic records are the combined effects of the subsurface ***,the study of DEI in elastic media is necessary for the accurate inversion of strong-scattering structures,such as salt *** this paper,we propose an elastic direct envelope inversion(EDEI)method based on wave mode *** define the objective function of EDEI using multi-component seismic data and derive its gradient *** reduce the coupling effects of multi-parameters,we introduce the wave mode decomposition method into the gradient calculation of *** update of Vp is primarily the contributions of decomposed *** approaches on Vs gradient calculation are proposed,*** the petrophysical relation and wave mode decomposition ***,we test the proposed method on a layered salt model and the SEG/EAGE salt *** results show that the proposed EDEI method can reconstruct reliable large-scale Vp and Vs models of strong-scattering salt *** successive elastic FWI can obtain high-precision inversion results of the strong-scattering salt *** proposed method also has a good anti-noise performance in the moderate noise level.

关键词： Direct envelope inversion Full waveform inversion Elastic wave Strong-scattering media Multi-parameter

A novel physics-informed framework for reconstruction of structural defects

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Applied Mathematics and Mechanics(English Edition) 2022年第11期43卷 1717-1730页

作者： Qi LI Fushun LIU Bin WANG DZLIU Zhenghua QIAN State Key Laboratory of Mechanics and Control of Mechanical Structures College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China College of Engineering Ocean University of ChinaQingdao 266100Shandong ProvinceChina School of Engineering University of East AngliaNorwich NR47TJU.K.

The ultrasonic guided wave technology plays a significant role in the field of non-destructive testing as it employs acoustic waves with the advantages of high propagation efficiency and low energy consumption during the inspect ***,the theoretical solutions to guided wave scattering problems with assumptions such as the Born approximation have led to the poor quality of the reconstructed ***,the scattering signals collected from industry sectors are often noised and *** address these issues,a novel physics-informed framework(PIF)for the quantitative reconstruction of defects by means of the integration of the data-driven method with the guided wave scattering analysis is proposed in this *** on the geometrical information of defects and initial results obtained by the PIF-based analysis of defect reconstructions,a deep-learning neural network model is built to reveal the physical relationship between the defects and the noisy detection *** learning model is then adopted to assess and characterize the defect profiles in structures,improve the accuracy of the analytical model,and eliminate the impact of the noise pollution in the process of *** demonstrate the advantages of the developed PIF for the complex defect reconstructions with the capability of denoising,several numerical examples are carried *** results show that the PIF has greater accuracy for the reconstruction of defects in the structures than the analytical method,and provides a valuable insight into the development of artificial intelligence(AI)-assisted inspection systems with high accuracy and efficiency in the fields of structural integrity and condition monitoring.

关键词： physics-informed deep-learning reconstruction of defects denoising

Analyses of the stability of submerged ice blocks

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Journal of Hydrodynamics 2017年第3期29卷 460-469页

作者：赵新练继建宋小艳 State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China

This paper proposes the critical conditions for a submerged ice block beneath an intact ice cover to become unstable,as a fundamental component of any numerical model to successfully predict the ice jam formation or the ice jam release *** flume model experimental and numerical simulation methods are both applied to analyze the stability of submerged ice *** flume model experiment is first conducted,and the experimental results indicate that the influencing factors of the stability of a submerged ice block include the relative length,the relative water depth and the relative *** was shown that the effect of the relative width on the stability of submerged ice blocks was not well *** on the experimental results,the k-eturbulence model is applied to establish a 3-D numerical model for studying the pressure distribution beneath submerged ice *** effects of the relative width on the Venturi pressure and the leading edge pressure are ***,according to the force balance equation and the moment balance equation,this paper proposes a computational formula for the sliding and underturning critical conditions of submerged ice blocks,and the results are in good agreement with the experimental results.

关键词： Submerged ice river ice ice block stability

Semi-theoretical analyses of the concrete plate perforated by a rigid projectile

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Acta Mechanica Sinica 2012年第6期28卷 1630-1643页

作者： Hao Wu Qin Fang Ya-Dong Zhang Zi-Ming Gong Institute of Structural Mechanics China Academy of Engineering Physics College of Defense Engineering PLA University of Science and Technology

Based on the three-stage perforation model, a semi-theoretical analysis is conducted for the ballistic per- formances of a rigid kinetic projectile impacting on concrete plates. By introducing the projectile resistance coefficients, dimensionless formulae are proposed for depth of penetra- tion （DOP）, perforation limit thickness, ballistic limit veloc- ity, residual velocity and perforation ratio, with the projec- tile nosed geometries and projectile-target interfacial fric- tion taken into account. Based on the proposed formula for DOP and lots of penetration tests data of normal and high strength concrete targets, a new expression is obtained for target strength parameter. By comparisons between the re- sults of the proposed formulae and existing empirical formu- lae and large amount of projectile penetration or perforation tests data for monolithic and segmented concrete targets, the validations of the proposed formulae are verified. It is found that the projectile-target interfacial friction can be neglected in the predictions of characteristic ballistic parameters. The dimensionless DOP for low-to-mid speed impacts of non-flat nosed projectiles increases almost linearly with the impact factor by a coefficient of 2/（nS）. The anti-perforation ability of the multilayered concrete plates is dependent on both the target plate thickness and the projectile impact velocity. The variation range of the perforation ratio is 1-3.5 for concrete targets.

关键词： Projectile Concrete Depth of penetration Perforation limit thickness Ballistic limit velocity Resid-ual velocity

Petroleum ether sub-fraction of rosemary extract improves hyperlipidemia and insulin resistance by inhibiting SREBPs

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Chinese Journal of Natural Medicines 2016年第10期14卷 746-756页

作者： XIE Zhi-Shen ZHONG Ling-Jun WAN Xiao-Meng LI Meng-Ning YANG Hua LI Ping XU Xiao-Jun State Key Laboratory of Natural Medicines China Pharmaceutical University Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases China Pharmaceutical University

As a culinary and medicinal herb, rosemary is widely used. The present work aimed to investigate the effects of rosemary extracts on metabolic diseases and the underlying mechanisms of action. Liver cells stably expressing SREBP reporter were used to evaluate the inhibitory effects of different fractions of rosemary extracts on SREBP activity. The obese mice induced by Western-type diet were orally administered with rosemary extracts or vehicle for 7 weeks, the plasma and tissue lipids were analyzed. SREBPs and their target genes were measured by quantitative RT-PCR. We demonstrated that the petroleum ether sub-fraction of rosemary extracts(PER) exhibited the best activity in regulating lipid metabolism by inhibiting SREBPs, while water and n-Bu OH sub-fraction showed the SREBPs agonist-effect. After PER treatment, there was a significant reduction of total SREBPs in liver cells. PER not only decreased SREBPs nuclear abundance, but also inhibited their activity, resulting in decreased expression of SREBP-1c and SREBP-2 target genes in vitro and in vivo. Inhibiting SREBPs by PER decreased the total triglycerides and cholesterol contents of the liver cells. In the mice fed with Western-type diet, PER treatment decreased TG, TC, ALT, glucose, and insulin in blood, and improved glucose tolerance and insulin sensitivity. Furthermore, PER treatment also decreased lipid contents in liver, brown adipose tissue, and white adipose tissue. Our results from the present study suggested that petroleum ether fraction of rosemary extracts exhibited the best potential of improving lipid metabolism by inhibiting SREBPs activity.

关键词： Rosemary SREBPs Hyperlipidemia Insulin resistance

A chitosan/amido-graphene oxide-based self-powered humidity sensor enabled by triboelectric effect

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Rare Metals 2021年第8期40卷 1995-2003页

作者： Bo-Hao Liu Guang-Zhong Xie Cheng-Zhen Li Si Wang Zhen Yuan Zai-Hua Duan Ya-Dong Jiang Hui-Ling Tai State Key Laboratory of Electronic Thin Films and Integrated Devices School of Optoelectronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengdu610054China

In this work,amido-graphene oxide(GO-NH_(2))loaded chitosan(CTS)composite material(CTS/GO-NH_(2))that acts as both the triboelectric and sensing film was prepared on rotary fan-shaped triboelectric nanogenerator for humidity *** with the pristine CTSbased triboelectric humidity sensor(CTS-THS)and GONH_(2)-THS,the CTS/GO-NH_(2)-based humidity sensor exhibited higher humidity response and better linearity in the relative humidity(RH)range of 18.7%RH-91.5%*** above results can be explained by the massive exposed and less concealed hydrophilic functional groups of CTS with the help of the wrinkle structure of GO-NH_(2).Meanwhile,the CTS/GO-NH_(2)-THS possessed good repeatability and acceptable hysteresis(~6.2%RH).Finally,a humidity sensing mechanism coupling triboelectric contact charging effect with electrons transfer principle under moisture environment was established to interpret the enhanced humidity sensing performance of the composite film-based *** work demonstrates that CTS/GONH_(2) composite film can be utilized to fabricate humidity sensors based on the triboelectric effect.

关键词： Chitosan Amido-graphene oxide Triboelectric nanogenerator Humidity sensors Hydrogen bonding interaction