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Numerical investigation of effects of “baffles-deceleration strip” hybrid system on rock avalanches

Journal of Mountain Science 2019年第2期16卷 414-427页

作者： BI Yu-zhang HE Si-ming DU Yan-jun SHAN Jie YAN Shuai-xing WANG dong-po sun Xin-po Institute of Geotechnical Engineering of Southeast University School of Transportation Southeast University Key Laboratory of Mountain Hazards and Surface Process Chinese Academy of Sciences Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chinese Academy of Sciences Center for Excellence in Tibet Plateau Earth Sciences University of Chinese Academy of Sciences State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology College of civil engineering Sichuan University of Science and Engineering

Arrays of baffles are usually installed in front of protection site to attenuate the flow energy of rock avalanches in mountainous areas. Optimization design is crucial for efficiency promotion in hazard energy dissipation engineering. In this study, a deceleration strip was added in the baffles protection system to optimize the traditional baffles system. The effects of the "baffles-deceleration strip" hybrid protection system was discussed in detail with the nails number and nails angle. This study presents details of numerical experiments using the discreteelement method(DEM). The effect of the optimization of hybrid protection system(nail angle and nail number) were investigated specifically, especially the impact force that avalanches exerted on structures. The results show that the maximum impact forces and kinetic energy of the rock avalanches decreases with the increase of the number and angle of the nail. Moreover, the distance between the toe and the bearing structure(L_m) is also a key factor. The shorter the distance L_m(30 m) is, the higher the maximum impact force are. The longer the distance L_m(70 m) is, the lower the maximum impact force are. Under the same size of the nails, increasing the numbers can enhance the dissipation ability of the hybrid protection system. Meanwhile, increasing itsangle can also enhance the dissipation ability. There are three key ways for nails attenuate rock avalanches:(i) block the fine particles directly;(ii) form the particles bridge between nails and baffles;(iii) dissipate the coarse particles energy directly. The effect of segregation in rock avalanches is crucial for the energy dissipation mechanism, which is a key factor to optimize the traditional baffle system.

关键词： Rock avalanches Baffles Hybrid system Energy dissipation Impact force

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瓜蒌- 薤白调节肠道菌群治疗冠心病模型大鼠的作用及机制

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中国组织工程研究 2025年第5期29卷 917-927页

作者：孙广瀚谢珍聪孙咪徐洋郭栋山东中医药大学第一临床医学院山东省济南市250014 山东中医药大学教师发展中心山东省济南市250355 山东中医药大学药物研究院山东省济南市250355

背景:基于网络药理学方法发现瓜蒌-薤白药对中主要生物活性化合物对冠心病有多功能作用;然而其治疗冠心病的机制尚未得到充分阐释。目的:探讨瓜蒌-薤白通过调节肠道微生物的组成改善冠心病的作用及机制。方法:40只SD大鼠按随机数字表法... 详细信息

背景:基于网络药理学方法发现瓜蒌-薤白药对中主要生物活性化合物对冠心病有多功能作用;然而其治疗冠心病的机制尚未得到充分阐释。目的:探讨瓜蒌-薤白通过调节肠道微生物的组成改善冠心病的作用及机制。方法:40只SD大鼠按随机数字表法分为空白组、模型组、阳性药组、药对组,除空白组外,其余大鼠连续灌胃脂肪乳剂和注射垂体后叶素制备冠心病大鼠模型。造模后模型组大鼠灌胃蒸馏水(10 mL/kg)进行对照,阳性药组大鼠每日灌胃辛伐他汀4 mg/kg,药对组每日灌胃瓜蒌-薤白7.56 g/kg,各组大鼠给药均为14 d。观察大鼠心电图、心肌病理及血脂变化,并通过16S rDNA测序技术研究大鼠经干预后肠道微生物结构。结果与结论:①心电图结果显示模型组ST抬高;阳性药组与药对组心电图无明显问题。②与空白组相比,模型组总胆固醇、三酰甘油、低密度脂蛋白胆固醇水平均显著增高(P0.05),Simpson指数降低(P<0.05)。⑤与空白组相比,模型组Desulfovibrionia、Muribaculaceae_norank等相对丰度升高,Clostridia、[Eubacterium]_coprostanoligenes_group_norank等相对丰度降低;与模型组相比,药对组WPS-2_norank、Muribaculaceae_norank等相对丰度升高,Clostridia、[Eubacterium]_coprostanoligenes_group_norank等相对丰度降低;阳性药组Desulfobacterota、[Eubacterium]_coprostanoligenes_group_norank等相对丰度升高,Firmicutes、Muribaculaceae_norank等相对丰度降低;与阳性药相比,药对组Desulfobacterota、Bacteroides等相对丰度升高,Firmicutes、[Eubacterium]_coprostanoligenes_group_norank等相对丰度降低;LEfSe结果发现差异显著的种群富集于药对组最多,其次是空白组、阳性药组,模型组最少。⑥结论:瓜蒌-薤白可以通过调节肠道菌群改善冠心病的发生发展,为进一步研发瓜蒌-薤白提供新的启示。

关键词： “瓜蒌-薤白”药对 16S rDNA 冠心病肠道菌群大鼠

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Refractive Index Engineering as a Novel Strategy toward Highly Transparent and Tough Sustainable polymer Blends

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Chinese Journal of polymer Science 2020年第12期38卷 1335-1344页

作者： Si-Ting sun Hang Wang dong Huang Ying-Li Ding Yang Zhang dong-po Song Kun-Yu Zhang Li Pan Yue-Sheng Li Department of polymer Science and Engineering School ofChemical Engineering and TechnologyTianjin UniversityTianin 300350China Department of Chemical Engineering Xiamen UniversityXiamen 361005China Tianjin Key Laboratory ofComposite and Functional Materials School ofMaterials Science and EngineeringTianjin UniversityTlanin 300350 China Cllaborotive lovation Center ofChemical Science and Engineering(injin) Tianjin 300072 China

High transparency and toughness are prerequisites for sustainable polymers if they are to find wide application as alternatives to petroleum-based ***,the utility of sustainable polymers such as commercially available polylactide(PLA)is limited by their inherent brittleness and high ***,toughening PLA-based materials via cost-effective blending strategies without sacrificing transparency remains a ***,we report a novel strategy involving active refractive index matching for creation of highly transparent and tough PLA ***,we engineered the refractive index of a promising renewable poly(epichlorohydrin-co-ethylene oxide)elastomer by introducing polar ionic moieties via a simple chemical method,and we blended the resulting ionomers with *** best blend showed an impact strength of>80 kJ/m2,an elongation at break of 400%,and high transparency(90%).These characteristics are of great importance for potential applications such as *** strategy offers a versatile new way to prepare high-performance sustainable polymer materials with excellent transparency.

关键词： polylactide Blending strategies Refraaive index matching poly(epichlorohydrin-co-ethylene oxide) Ionomers

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Interchange between grooming and infant handling in female Tibetan macaques(Macaca thibetana)

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Zoological Research 2019年第2期40卷 139-145页

作者： Qi Jiang dong-po Xia Xi Wang Dao Zhang Bing-Hua sun Jin-Hua Li School of Resource and Environmental Engineering Anhui University School of Life Science Anhui University School of Life Science Hefei Normal University

In some non-human primates, infants function as a social tool that can bridge relationships among group members. Infants are a desired commodity for group members, and mothers control access to them. The biological market theory suggests that grooming is widespread and represents a commodity that can be exchanged for infant handling. As a limited resource, however, the extent to which infants are interchanged between mothers(females with an infant) and non-mothers(potential handlers,females without an infant) remains unclear. In this study, we collected behavioral data to investigate the relationship between grooming and infant handling in free-ranging Tibetan macaques(Macaca thibetana)at Mt. Huangshan, China. Our results showed that females with infants received more grooming than females without infants. After her infant was handled,mother females received more grooming than they did during daily grooming interactions. However, with the increasing number of infants within the social group, both the grooming that mothers received and the grooming that non-mothers invested for handling infants decreased. We also found that non-mothers invested more time in grooming to gain access to younger infants than older infants. Our results provide evidence that infants are social commodities for both mother and non-mother females. Mothers use infants for obtain grooming and non-mothers use grooming to gain access to infants. The current study implies a bidirectional and complex interchange pattern between grooming and infant handling to compensate for the dyadic grooming disparity in non-human primates.

关键词： Tibetan macaques (Macaca thibetana) Interchange Infant handling Grooming Biological market theory

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Hierarchical Assemblies of Bottlebrush/Homopolymer Blends: Tailoring Phase Interfacial Curvature for Tunable Photonics

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Chinese Journal of Chemistry 2023年第13期41卷 1566-1574页

作者： Han Yi Yuesheng Li dong-po Song Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin300350 China

Organized spontaneous emulsification (OSE) produces ordered water-in-oil-in-water (W/O/W) multiple emulsion droplets stabilized by bottlebrush block copolymer (BBCP) surfactants, such as (polynorbornene-g-polystyrene)-b-(polynorbornene-g-polyethylene oxide) (PS-b-PEO), templating ordered porous particles with visible structural colors. Here, homopolymer polystyrenes (hPS) were used to swell the PS domain and thus to effectively increase the W/O interfacial curvature of the internal droplets. By variation of hPS concentration, pore diameter is largely tunable from 34 to over 210 nm, leading to tunable photonic bandgaps in the whole visible spectrum. The ratio (α) of molecular weight of hPS relative to that of the PS side chains of the BBCP can greatly influence their spatial distribution within the PS domain. For α ≤ 1, uniform solubilization of the hPS chains into the side chains of BBCP is achieved leading to a homogeneous porous structure. For α > 1, local solubilization of the hPS chains at interface of the internal droplets is disclosed at relatively low concentrations of hPS (≤ 42 wt%), resulting in a small change in pore diameter. For contrast, a rapid increase of the W/O interfacial curvature was observed upon further increase of the hPS content (> 42 wt%) through an evident influence on the OSE procedure.

关键词： Block copolymer Self-assembly porous polymers Copolymers Microstructures

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Dynamic response and optimization of an inclined steel rock shed by the graded energy dissipating method

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Journal of Mountain Science 2019年第1期16卷 138-152页

作者： WU Yong HE Si-ming LI Xin-po Wang dong-po Key Laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of Sciences Institute of Mountain Hazards and Environment Chinese Academy of Sciences State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology

Blocking rockfalls directly by reinforced concrete(RC) flat sheds with thick sand cushions is an outdated method. Such conventional sheds typically accumulate rock heavily, and become progressively damaged and are difficult to repair, and are very costly. To address these problems, we propose a new structure called a Graded Dissipating Inclined Steel Rock(GDISR) shed that utilizes the graded energy dissipation method. Here, we study the dynamic response of the GDISR shed with model test and numerical simulation, and give its optimization design combining with a practical engineering case. Our results show that the optimized modular E-block and corrugated steel tube can deform to sufficiently absorb the energy of different impact intensities. This efficiently and economically provides GDISR sheds with two security lines. Compared with conventional RC sheds, GDISR sheds with optimal incline have a more efficient anti-impact function, are faster and easier to repair, and are much simpler and cheaper to build.

关键词： Dynamic response Optimization design Graded dissipating inclined steel rock shed

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明渠扩散段急流运动特性及调控方法研究综述

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华北水利水电大学学报（自然科学版） 2014年第4期35卷 1-6页

作者：孙东坡李林昊赵宝帅李明佳王宏飞杨晓华北水利水电大学水利学院河南郑州450045

依据文献分析了有限宽度水槽突然扩散、固定扩散角渐变扩散、无边界平板扩散和急流扩散4种典型明渠扩散段水流的共同流动特征.给出了有限宽度水槽突然扩散段水流宽度的沿程发展规律,以及在平底明渠急流扩散段设计时,为防止水流脱离的扩... 详细信息

依据文献分析了有限宽度水槽突然扩散、固定扩散角渐变扩散、无边界平板扩散和急流扩散4种典型明渠扩散段水流的共同流动特征.给出了有限宽度水槽突然扩散段水流宽度的沿程发展规律,以及在平底明渠急流扩散段设计时,为防止水流脱离的扩散角计算方法和突然扩展区急流扩散的边界方程;通过不同底坡比降的试验和原型资料分析,论述了陡坡扩散区水深沿程变化特点、沿程各断面横向分布规律,介绍了陡坡上水平扩散角的计算方法与扩散角最大值的存在.通过大扩散角水槽试验,发现在扩散段不同流态的过渡水流现象及稳定性不一样.上游来流为急流时,下游水跃进入扩散段就是水流失稳、主流偏转的开始;采用潜没式三角翼可以防止扩散段回流发生,提高过流均衡性.

关键词：明渠扩散段急流水流分离回流调控方法

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β-Cyclodextrin promoted oxidation of aldehydes to carboxylic acids in water

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Chinese Chemical Letters 2009年第2期20卷 139-142页

作者： dong po Shi Hong Bing Ji College of Chemistry and Environmental Engineering Yangtze University Jingzhou 434023 China School of Chemistry and Chemical Engineering of sun Yat-Sen University Guangzhou 510275 China

A facile, efficient and substrate-selective oxidation of aldehydes to carboxylic acids with NaClO catalyzed by β-cyclodextrin in water has been developed. A series of aldehydes which could form inclusion complex with... 详细信息

关键词： Substrate-selective Oxidation β-Cyclodextrin (β-CD) Aldehydes

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Recent development of casing treatments for aeroengine compressors

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Chinese Journal of Aeronautics 2019年第1期32卷 1-36页

作者： Xiaofeng sun Xu dong Dakun sun Fluid and Acoustic Engineering Laboratory Beihang University Collaborative Innovation Center for Advanced Aero-Engine Beihang University

Casing treatment is a mature stabilization technique which has been widely applied on aero-engines for modern aircrafts and turbo-chargers for automobiles. After the investigations of half century since the 1960 s, this technique has been well developed for various configurations with different effectiveness. From the perspective of stabilization mechanism, this paper roughly categorizes the configurations of casing treatment into two types: traditional ones which work by affecting the flow structure of blade tip region; a novel one named as Stall Precursor-Suppressed(SPS) casing treatment. The effectiveness of both types will be demonstrated for their applications on axial compressors and centrifugal compressors with uniform or distorted inlet. And the stabilization mechanism of casing treatments for regular types and SPS one will also be explained respectively. In addition, this review will summarize the methodologies of casing treatments with the numerical simulations for regular grooved configurations and the eigenvalue approach for SPS casing *** forward to the future of compressor stabilization, casing treatment technique will still exist as a general and inexpensive option, and the exploration for its effectiveness and mechanism will be deeper with the development of computational fluid dynamics and advanced measurement techniques.

关键词： Casing treatment Compressor Compressor stability Rotating stall Stall margin

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Impinge Weyl advantages on light

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Light(Science & Applications) 2023年第11期12卷 323-324页

作者： Xiaomu Wang dong sun School of Electronic Science and Engineering Nanjing UniversityNanjing 210093China International Center for Quantum Materials School of PhysicsPeking UniversityBejing100871China

Weyl semimetals are emerging topological materials with intriguing physical *** this exotic matter may lead to novel photonic and optoelectronic applications.

关键词： properties. topological Weyl

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