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Multiple evidences indicate no relationship between prehistoric disasters in Lajia site and outburst flood in upper Yellow River valley, China

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Science China Earth Sciences 2018年第4期61卷 441-449页

作者： DONG GuangHui zhang fanyu LIU FengWen zhang DongJu ZHOU AiFeng YANG YiShi WANG GongHui MOE Key Laboratory of Western China's Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou University Key Laboratory of Mechanics on Disaster and Environment in Western China (Ministry of Education) Department of Geological EngineeringLanzhou University Research Center on Landslides Disaster Prevention Research InstituteKyoto University

All around the world, ancient legends exist about the Great Flood, and the influence of the Great Flood in human evolutionary history is a hotly debated topic. In China, the legend of the prehistoric Great Flood and Yu the Great's flood control has a long history and is considered to be closely linked to the establishment of the Xia Dynasty. However, there is a lack of solid scientific evidence. Against this issue, some scholars have proposed that an earthquake around 1920 BCE in the Guanting Basin along the upper reaches of the Yellow River led to the creation of a lake by damming in the Jishi Gorge and that the outburst of water from that lake led to the massive flood in the Yellow River region. These studies provided new scientific evidence for the Chinese legend. In this paper, we date skeletal samples embedded in earthquake sand blasting from the Lajia site, analyze remains from natural disasters(such as earthquakes and floods) and also archaeological remains. In addition, we compared the skeletal samples dating with that of sediments from the dammed-up lake. Our results are inconsistent with those of previous scholars. The earthquake at the Lajia site occurred no earlier than 1800 BCE, and the dammed-up lake in Jishi Gorge had disappeared by 3600 BCE. Thus, the formation and outburst of the dammed lake, the sudden death of ancient humans at the Lajia site and the ancient earthquake were independent events occurring at different times. In addition, the massive flood in the upper reaches of the Yellow River did not actually happen. Thus, we argue against and invalidate the hypothesis that the massive flood was related to Yu the Great's flood control and the establishment of the Xia Dynasty.

关键词：科学证据大洪水自然灾难黄河爆发地点中国山谷

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Relationships between Landslide Types and Topographic Attributes in a Loess Catchment,China

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Journal of Mountain Science 2012年第6期9卷 742-751页

作者： zhang fanyu CHEN Wenwu LIU Gao LIANG Shouyun KANG Chao HE Faguo Key Laboratory of Mechanics on Disaster and Environment in Western China(Ministry of Education of China) and Department of Geological EngineeringLanzhou UniversityLanzhou 730000China Department of Civil and Environmental Engineering University of AlbertaEdmontonAlbertaT6G 2W2Canada

Topographic attributes have been identified as the most important factor in controlling the initiation and distribution of shallow landslides triggered by rainfall.As a result,these landslides influence the evolution of local surface topography.In this research,an area of 2.6 km 2 loess catchment in the Huachi County was selected as the study area locating in the Chinese Loess Plateau.The landslides inventory and landslide types were mapped using global position system(GPS) and field mapping.The landslide inventory shows that these shallow landslides involve different movement types including slide,creep and fall.Meanwhile,main topographic attributes were generated based on a high resolution digital terrain model(5 m × 5 m),including aspect,slope shape,elevation,slope angle and contributing area.These maps were overlaid with the spatial distributions of total landslides and each type of landslides in a geographic information system(GIS),respectively,to assess their spatial frequency distributions and relative failure potentials related to these selected topographic attributes.The spatial analysis results revealed that there is a close relation between the topographic attributes of the postlandsliding local surface and the types of landslide movement.Meanwhile,the types of landslide movement have some obvious differences in local topographic attributes,which can influence the relative failure potential of different types of landslides.These results have practical significance to mitigate natural hazard and understandgeomorphologic process in thick loess area.

关键词：数字地形模型中国黄土高原浅层滑坡滑坡类型属性山体滑坡流域全球定位系统

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Ferric acetylacetonate/covalent organic framework composite for high performance photocatalytic oxidation

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Green Energy & Environment 2022年第6期7卷 1281-1288页

作者： Mingzhao Xu Lifei Liu Jianling zhang fanyu zhang Gang Chen Qiang Wan Yufei Sha Xiuyan Cheng Zhuizhui Su Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Colloid and Interface and ThermodynamicsCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing100190China School of Chemistry and Chemical Engineering University of Chinese Academy of SciencesBeijing100049China School of Chemical Sciences University of Chinese Academy of SciencesPhysical Science LaboratoryHuairou National ComprehensiveScience CenterBeijing100190China

Ferric acetylacetonate/covalent organic framework(Fe(acac)_(3)/COF)composite was synthesized by interfacial polymerization method at room temperature.The crystal structure,morphology and porosity property of the composite were characterized by X-ray diffraction,scanning electron microscope,transmission electron microscope and nitrogen adsorption.The interaction between Fe(acac)_(3) and COF was investigated by Fourier transform infrared spectra and X-ray photoelectron spectroscopy.The Fe(acac)_(3)/COF composite was used as a photocatalyst for the oxidation of benzyl alcohol under mild conditions.It exhibits high activity and selectivity for the reaction,of which the mechanism was investigated by determining its photoelectric properties.The Fe(acac)_(3)/COF catalyst developed in this work has application potential in other photocatalytic reactions.

关键词： Covalent organic framework Photocatalysis Hybrid catalyst Benzyl alcohol oxidation Interfacial polymerization

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Ultra-small UiO-66-NH_(2)nanoparticles immobilized on g-C_(3)N_(4)nanosheets for enhanced catalytic activity

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Green Energy & Environment 2022年第3期7卷 512-518页

作者： Zhuizhui Su Bingxing zhang Xiuyan Cheng fanyu zhang Qiang Wan Lifei Liu Xiuniang Tan Dongxing Tan Lirong Zheng Jianling zhang Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Colloid and Interface and ThermodynamicsCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing100190China School of Chemical Sciences University of Chinese Academy of SciencesPhysical Science LaboratoryHuairou National ComprehensiveScience CenterBeijing100190China Beijing Synchrotron Radiation Facility(BSRF) Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China

UiO-66-NH_(2),an important metal-organic framework,is usually synthesized by solvothermal method and the particle size is generally larger than 200 nm,which limits its catalytic applications in chemical reactions.It is very meaningful to produce UiO-66-NH_(2) nanoparticles with ultrasmall size,but remains challenging.Herein,we synthesized UiO-66-NH_(2) nanoparticles in size of 8-15 nm that are immobilized on g-C_(3)N_(4)nanosheets.Compared with the UiO-66-NH_(2) synthesized by the traditional solvothermal method(>200 nm),the ultra-small UiO-66-NH_(2) nanoparticles immobilized on g-C_(3)N_(4)have more unsaturated coordination positions and increased Lewis acidity.Owing to these combined advantages,the ultra-small UiO-66-NH_(2)nanoparticles exhibit greatly improved catalytic activity for Meerwein-Ponndorf-Verley reaction than larger UiO-66-NH_(2)particles.

关键词： particles catalytic meaningful

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防疫物资“无接触”机器人配送优化研究

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计算机工程与应用 2023年第17期59卷 295-307页

作者：张省张樊宇郑州轻工业大学经济与管理学院郑州450001

新型冠状病毒传感性强,致病率高,如何避免防疫物资在配送时人际接触是疫情防控的一大难题。考虑配送机器人具有小快灵且环境适应性强等特点,以配送时间最短为主目标,以配送路径最短为次目标建立集中式控制多种类机器人协同配送工作模式... 详细信息

新型冠状病毒传感性强,致病率高,如何避免防疫物资在配送时人际接触是疫情防控的一大难题。考虑配送机器人具有小快灵且环境适应性强等特点,以配送时间最短为主目标,以配送路径最短为次目标建立集中式控制多种类机器人协同配送工作模式。在全局路径规划阶段,改进A*算法以解决其存在拐点多、冗余路径长等缺点,在局部路径规划阶段改进动态窗口法(DWA)使其能够选择更优路径,最终将两种算法融合使机器人能够达到择优路径行驶并在行驶中达到自主避障的效果。以新冠病毒感染疫情(COVID-19)下河南省人民医院医用防护物资配送为例,对模型与算法进行验证。结果表明,融合算法与传统算法相比,鲁棒性、路径长度、配送用时和路径平滑度都得到了不同程度的优化,该算法可为医院内部机器人无接触式防疫物资配送模式提供参考。

关键词： “无接触”配送防疫物资机器人路径优化

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Ionic liquids produce heteroatom-doped Pt/TiO2 nanocrystals for efficient photocatalytic hydrogen production

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Nano Research 2019年第8期12卷 1967-1972页

作者： Xiuniang Tan Jianling zhang Dongxing Tan Jinbiao Shi Xiuyan Cheng fanyu zhang Lifei Liu Bingxing zhang Zhuizhui Su Buxing Han Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of ColloidInterface and Chemical ThermodynamicsCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Physical Science Laboratory Huairou National Comprehensive Science CenterBeijing 101400China

It is of great importance to develop facile strategies to synthesize catalysts with desirable compositions and structures for high-performance photocatalytic hydrogen generation. In this work, we put forward an ionic liquid assisted one-pot route for the synthesis of heteroatom-doped Pt/TiO2 composite material. This route is simple, environmentally benign and adjustable owing to the designable properties of ionic liquids. The as-synthesized Pt/TiO2 nanocrystals exhibit high activity and stability for the photocatalytic hydrogen generation under simulated solar irradiation. This method can be easily applied to the synthesis of various kinds of metal/TiO2 composites doped with desirable heteroatoms (e.g., F, Cl, Br, etc).

关键词： ionic liquid titanium dioxide platinum heteroatom photocatalyst

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Supercritical CO2 produces the visible-light-responsive TiO2/COF heterojunction with enhanced electron-hole separation for highperformance hydrogen evolution

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Nano Research 2020年第4期13卷 983-988页

作者： Lifei Liu Jianling zhang Xiuniang Tan Bingxing zhang Jinbiao Shi Xiuyan Cheng Dongxing Tan Buxing Han Lirong Zheng fanyu zhang Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of ColloidInterface and Chemical ThermodynamicsCASResearch/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Physical Science Laboratory Huairou National Comprehensive Science CenterBeijing 101400China Beijing Synchrotron Radiation Facility(BSRF) Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

To construct the heterojunctions of TiO2 with other compounds is of great importance for overcoming its inherent shortages and improving the visible-light photocatalytic performance.Here we propose the construction of TiO2/covalent organic framework(COF)heterojunction with tight connection by a supercritical CO2(SC CO2)method,which helps bridging the transformation paths for photo-induced charge between T i02 and COF.The produced T i02/COF heterojunction performs a H2 evolution of 3,962 nmol·g^-1·h^-1 under visible-light irradiation,which is-25 times higher than that of pure TiO2 and 4.5 folds higher than that of TiO2/COF synthesized by the conventional solvothermal method.This study opens up new possibilities for constructing heterojunctions for solar energy utilization.

关键词： supercritical CO2 covalent organic fram ework(COF) TiO2 H2 production visible light

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基于内外功率比的非直线坡面型边坡的稳定系数研究

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地质科技通报 2022年第6期41卷 189-199页

作者：程云祥张彤炜兰恒星张帆宇张虎元兰州大学西部灾害与环境力学教育部重点实验室兰州730000 兰州大学土木工程与力学学院兰州730000 长安大学地质工程与测绘学院西安710064 中国科学院地理科学与资源研究所北京100101

在边坡稳定性上极限分析中,由于考虑了材料的理想弹塑性本构关系与相关流动法则,相比极限平衡法更符合岩土材料的特征。在以往的二维边坡极限分析上限法中,要求坡面形态为规则的直线,而无论是天然边坡还是人工边坡,边坡的坡面形态往往... 详细信息

在边坡稳定性上极限分析中,由于考虑了材料的理想弹塑性本构关系与相关流动法则,相比极限平衡法更符合岩土材料的特征。在以往的二维边坡极限分析上限法中,要求坡面形态为规则的直线,而无论是天然边坡还是人工边坡,边坡的坡面形态往往并非规则的直线。此外,以往的边坡极限上限分析中得到的稳定数N_(s)=c/γH主要针对土坡的临界高度计算,且未考虑孔压等外力对边坡施加的外功率。不同于传统极限平衡法采用静力学的平衡条件,本研究针对非直线型坡面边坡稳定性问题,假定滑动面为对数螺旋线,基于极限分析上限定理和虚功原理,提出了一种边坡发生旋转破坏时旋转中心的确定方法,推导出了非直线型坡面边坡的重力虚功功率和能量平衡方程的解析解,并提出了基于内、外功率之比的稳定系数K用以评价边坡的稳定性。通过算例比较了不同形态天然边坡的稳定性和人工削坡对边坡稳定性的影响,并分析了边坡的坡度(β)、土体的内摩擦角(φ)、黏聚力(c)以及孔压系数(ru)对稳定系数K的影响规律。对于坡度较大的边坡,通过削坡改变坡面形态提高了边坡的稳定系数K。稳定系数K随黏聚力的增加而非线性增大,随孔压系数的增加而降低。当黏聚力相对于孔压系数对边坡稳定性影响更大时,稳定系数K随内摩擦角的增加而增大;反之,稳定系数K则随内摩擦角的增加而减小。以上结果符合对边坡稳定性分析的普遍认知,验证了模型的合理性。另外,通过将该方法与传统的Bishop法的计算结果进行对比,发现安全系数F_(s)=1与稳定系数K=0的临界状态物理意义相同,稳定系数K随黏聚力非线性增加,更符合边坡的渐进破坏过程。

关键词：土质边坡非直线坡面极限上限分析虚功功率稳定系数

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Mutation of SlARC6 leads to tissue-specific defects in chloroplast development in tomato

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Horticulture Research 2021年第1期8卷 1807-1817页

作者： Jiang Chang fanyu zhang Haiyang Qin Peng Liu Jianfeng Wang Shuang Wu College of Horticulture FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems BiologyFujian Agriculture and Forestry UniversityFuzhou 350002China

The proliferation and development of chloroplasts are important for maintaining the normal chloroplast population in plant tissues.Most studies have focused on chloroplast maintenance in leaves.In this study,we identified a spontaneous mutation in a tomato mutant named suffulta(su),in which the stems appeared albinic while the leaves remained normal.Map-based cloning showed that Su encodes a DnaJ heat shock protein that is a homolog of the Arabidopsis gene AtARC6,which is involved in chloroplast division.Knockdown and knockout of SlARC6 in wild-type tomato inhibit chloroplast division,indicating the conserved function of SlARC6.In su mutants,most mesophyll cells contain only one or two giant chloroplasts,while no chloroplasts are visible in 60%of stem cells,resulting in the albinic phenotype.Compared with mature tissues,the meristem of su mutants suggested that chloroplasts could partially divide in meristematic cells,suggesting the existence of an alternative mechanism in those dividing cells.Interestingly,the adaxial petiole cells of su mutants contain more chloroplasts than the abaxial cells.In addition,prolonged lighting can partially rescue the albinic phenotypes in su mutants,implying that light may promote SlACR6-independent chloroplast development.Our results verify the role of SlACR6 in chloroplast division in tomato and uncover the tissue-specific regulation of chloroplast development.

关键词： specific dividing lighting

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Human-induced landslide on a high cut slope: a case of repeated failures due to multi-excavation

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Journal of Rock Mechanics and Geotechnical Engineering 2012年第4期4卷 367-374页

作者： fanyu zhang Gao Liu Wenwu Chen Shouyun Liang Ransheng Chen Wenfeng Han Key Laboratory of Mechanics on Disaster and Environment in Western China Ministry of Education Department of Geological Engineering School of Civil Engineering and MechanicsLanzhou University Department of Civil Engineering Tianjin Institute of Urban Construction

The paper attempts to represent a case of repeated failures on a high cut slope due to multi-excavation. The characteristics of each failure induced by excavation are analyzed through geological investigation, and then a geological model at different failure stages is proposed. The geological analysis shows that the excavation-induced repeated failures are related to the exposure of the weak bedding plane and the toe unloading of the cut slope, Numerical modeling is conducted based on a sequential method, taking into account the main failure stages of cut slope. The simulation results fairly coincide with the practical phenomena observed in field. It is shown that the decrease in normal stress of displaced mass on cut slope will induce the increase in shear stress in bedding planes and that at the toe of the cut slope. The released stress leads to repeated gravitational instabilities of cut slope due to the decrease in normal stress and the increase in shear stress along the bedding planes of mudstone.

关键词： landslide repeated failures multi-excavation instability of cut slope human activity

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