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Local Scour and the Laws of Scour Pit's Shape Downstream of Debris Flow Sabo Dam

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Journal of Mountain Science 2013年第6期10卷 1063-1073页

作者： PAN Hua-li YANG Shun OU Guo-qiang huang jiang-cheng Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences Graduate University of Chinese Academy of Sciences Asian International Rivers Center Yunnan University Yunnan Key Laboratory for International Rivers and Transboundary Ecology Security

The erosion shape and the law of development of debris flow sabo dam downstream is a weak part in the study on debris flow erosion. The shape and development of scour pit have an important effect on the stability and safety of debris flow sabo dam, which determines the foundational depth of the dam and the design of protective measures downstream. Study on the scouring law of sabo dam downstream can evaluate the erosion range and reasonably arrange auxiliary protective engineering. Therefore, a series of flume experiments are carried out including different debris flow characteristics （density is varying from 1.5 t/m3 to 2.1 t/m~） and different gully longitudinal slopes. The result shows that the scour pit appears as an oval shape in a plane and deep in the middle while superficial at the ends in the longitudinal section, the position of the maximum depth point moves towards downstream with an increase of flume slope angle. The maximum depth of scour pit is mainly affected by the longitudinal slope of gully, density of debris flow, and the characteristics of gully composition （particle size and the viscosity of soil）. The result also indicates that the viscosity of soil will weaken the erosion extent. The interior slopes of scour pit are different between the upstream and the downstream, and the downstream slope is smaller than the upper one. For the viscous and non-viscous sands with the same distribution of gradation, the interior slope of non- viscous sand is smaller than the viscous *** to tbe regression analysis on the experimental data, the quantitative relationship between the interior slope of scour pit, slope of repose under water and the longitudinal slope of gully is established and it can be used to calculate the interior slope of scour pit. The results can provide the basis for the parameter design of the debris flow control engineering foundation.

关键词： Scour pit Debris flow Sabo dam Scouring law Interior slope Flume experiment

Substituent effects on the EPR aN values of symmetrically para-disubstituted diphenyl nitroxides

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Chinese Journal of Chemistry 1994年第6期12卷 516-523页

作者： ZHANG, Yu-huang jiang, Bin ZHOU, cheng-Ming jiang, Xi-KuiShanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Lu, Shanghai 200032, China Shanghai Institute of Organic Chemistry Chinese Academy of Sciences 354 Fenglin Lu Shanghai 200032 China

Nitrogen hyperfine splitting constants (aN values) of seven symmetrically para-disubstituted diphenyl nitroxides (1-Y's) were measured by EPR and used in conjunction with five literature values in our correlation analysis. The correlation of these ON values by single-parameter Eq. 1 and dual-parameter Eq. 2 shows that the application of Eq. 2 does not significantly improve the correlation. But our data can also be interpreted by the proposition that the spin-delocalization effect is not completely nonexistent and that it might have revealed itself through the aN values of two very weakly polar substituents with pronounced spin-stabilizing abilities, i.e., SMe and SiMe3.

关键词： EPR diphenyl nitroxides correlation analysis dual-parameter equation.

Microstructure Evolution and Mechanism of Strength Development of Fly Ash Paste

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 152-163页

作者： MA Shuzhao WU Shunchuan huang Mingqing cheng Haiyong jiang Guanzhao NIU Yonghui LIU Zemin SUN Wei Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093China Zijin School of Ge-ology and Mining Fuzhou UniversityFuzhou 350108China

Three types of activators such as sodium hydroxide,calcium oxide and triethanolamine(TEA)are used to establish different activation environments to address the problems associated with the process of activating fly ash *** conducted mechanical tests and numerical simulations to understand the evolution of microstructure,and used environmental scanning electron microscopy(ESEM)and energy dispersive spectroscopy(EDS)techniques to analyze the microenvironments of the *** mechanical properties of fly ash paste under different activation conditions and the changes in the microstructure and composition were *** results revealed that under conditions of low NaOH content(1%-3%),the strength of the sample increased *** the content exceeded 4%,the rate of increase in strength *** on the results,the optimal NaOH content was identified,which was about 4%.A good activation effect,especially for short-term activation(3-7 d),was achieved using TEA under high doping *** activation effect was poor for long-term strength after 28 *** CaO content did not significantly affect the degree of activation *** maximum effect was exerted when the content of CaO was 2%.The virtual cement and concrete testing laboratory(VCCTL)was used to simulate the hydration process,and the results revealed that the use of the three types of activators accelerated the formation of Ca(OH)_(2) in the *** activators also corroded the surface of the fly ash particles,resulting in a pozzolanic *** active substances in fly ash were released efficiently,and hydration was *** pores were filled with hydration products,and the microstructure changed to form a new frame of paste filling that helped improve the strength of fly ash paste.

关键词： paste filling fly ash activator unconfined compressive strength microstructure hydration simulation

Preparation of FeCoNi medium entropy alloy from Fe^(3+)-Co^(2+)-Ni^(2+)solution system

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 92-101页

作者： Zongyou cheng Qing Zhao Mengjie Tao Jijun Du Xingxi huang chengjun Liu Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China Engineering Research Center of Frontier Technologies for Low-carbon Steelmaking(Ministry of Education) Shenyang 110819China

In recent years,medium entropy alloys have become a research hotspot due to their excellent physical and chemical *** controlling reasonable elemental composition and processing parameters,the medium entropy alloys can exhibit similar properties to high entropy alloys and have lower *** this paper,a FeCoNi medium entropy alloy precursor was prepared via sol-gel and coprecipitation methods,respectively,and FeCoNi medium entropy alloys were prepared by carbothermal and hydrogen *** phases and magnetic properties of FeCoNi medium entropy alloy were *** showed that FeCoNi medium entropy alloy was produced by carbothermal and hydrogen reduction at 1500℃.Some carbon was detected in the FeCoNi medium entropy alloy prepared by carbothermal *** alloy prepared by hydrogen reduction was uniform and showed a relatively high ***,the hydrogen reduction product exhibited better saturation magnetization and lower coercivity.

关键词： medium entropy alloy sol-gel co-precipitation carbothermal hydrogen reduction

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澜沧江中下游河流泥沙特性分析

四川大学学报（工程科学版） 2010年第3期42卷 112-120页

作者：黄江成傅开道何大明中国科学院成都山地灾害与环境研究所四川成都610041 中国科学院山地灾害与地表过程重点实验室四川成都610041 中国科学院研究生院北京100049 云南大学亚洲国际河流中心云南昆明650091

为了探究漫湾水库拦沙对上下游干支流河道泥沙理化特性的影响,运用激光粒度、X衍射、X荧光光谱的实验测试方法,对澜沧江中下游干流和主要支流河道的悬移质泥沙及其床沙的理化特性进行了测验。结果显示:澜沧江中下游悬移质泥沙粒径频率... 详细信息

为了探究漫湾水库拦沙对上下游干支流河道泥沙理化特性的影响,运用激光粒度、X衍射、X荧光光谱的实验测试方法,对澜沧江中下游干流和主要支流河道的悬移质泥沙及其床沙的理化特性进行了测验。结果显示:澜沧江中下游悬移质泥沙粒径频率曲线多为单峰态,粒度范围较宽,分选性较好,床沙粒径频率曲线呈多折状且很陡,分选性差;泥沙的主要矿物组成为石英,其含量集中在60%～80%范围内;悬沙元素组分具有较好的一致性,床沙微量元素含量从旧州至界碑有下降的趋势;漫湾水库拦沙效应对泥沙的粒度,矿物组分的空间分布存在较大影响,对除硅(Si)以外的常量元素组成影响不大,对重金属元素有一定的拦截作用。研究结果可为澜沧江干流在建的多个水电站对泥沙组成的影响提供参考。

关键词：泥沙特征水库拦沙粒度分析矿物组成澜沧江

Unraveling the impacts of intermolecular interaction on morphology evolution for highly efficient organic solar cells and modules

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Science China Chemistry 2025年第1期68卷 264-272页

作者： Xueqing Ma Yingying cheng Yuqiang Liu Xinming Zheng Guangliu Ran Hongxiang Li Xinyue Cui Andong Zhang Wenkai Zhang Pei cheng Wenchao huang Zhishan Bo Beijing Key Laboratory of Energy Conversion and Storage Materials College of Chemistry Beijing Normal University College of Textiles and Clothing State Key Laboratory of Bio-fibers and Eco-textiles Qingdao University Key State Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of Technology Department of Physics and Applied Optics Beijing Area Major Laboratory Center for Advanced Quantum Studies Beijing Normal University State Key Laboratory of Polymer Materials Engineering College of Polymer Science and Engineering Sichuan University

Understanding the effect of intermolecular interaction on the growth dynamic of active layers is critical for advancing organic solar cells(OSCs). However, the diverse structure of donors and acceptors makes the research challenging. Additives with customizable structures and properties could simplify this complexity. Herein, we meticulously tailor two additives of 3,4-ethylenedioxythiophene(EDOT) and 2,5-dibromo-3,4-ethylenedioxythiophene(DBEDOT), possessing distinct intermolecular interaction features to elaborate the inherent relationship. It is found that varied interaction strengths can alter film formation processes. The enhanced intermolecular interaction between the DBEDOT and non-fullerene acceptor BTP-e C9-4F results in pre-aggregation and longer crystallization duration of BTP-e C9-4F, facilitating the formation of films with compact molecular packing and decent phase separation. Thus, exciton dissociation and charge transport become more efficient. Finally, devices processed with DBEDOT exhibit a remarkable power conversion efficiency of 19.35% in small-area OSCs and 14.11% in bladecoated 5 cm × 5 cm organic solar mini-modules. Especially, OSCs can maintain 80% of their initial efficiency after continuous annealing at 85 °C for over 2,100 h.

关键词： organic solar cell non-fullerene acceptor film growth molecular packing intermolecular interaction

When AI meets sustainable 6G

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Science China(Information Sciences) 2025年第1期68卷 4-22页

作者： Xiaohu YOU Yongming huang cheng ZHANG Jiaheng WANG Hao YIN Hequan WU National Mobile Communications Research Laboratory Southeast University Purple Mountain Laboratories Chinese Academy of Military Science China Information Communication Technologies Group

Sixth-generation(6G) networks are anticipated to achieve transformative advancements, characterized by extreme connectivity, deep integration with artificial intelligence(AI) and sensing, and airground integration. The evolution of 6G exhibits two major trends: ubiquitous intelligence and sustainability. The former aims to embed state-of-the-art AI technology into the 6G network, from the physical layers to applications, while the latter emphasizes reducing energy consumption while enhancing network performance to address environmental concerns. Despite the amazing progress in recent years, AI advancements come with substantial increases in data and computational overhead, posing critical challenges for integrating AI into sustainable 6G networks. First, high energy consumption from large datasets and heavyweight AI models contradicts6G's green goals. Second, the precise collection of large datasets, message delivery latency, and inference delays in AI models pose challenges for real-time tasks in 6G. Third, the uninterpretability and unpredictability of AI models complicate meeting the stringent requirements for controllable transmission in dynamic wireless environments. Addressing these challenges and achieving sustainable 6G with ubiquitous intelligence calls for a revolutionary design of 6G architecture and AI frameworks. To this end, this paper introduces a novel and practical methodology for green, real-time, and controllable 6G native intelligence,starting with knowledge graph(KG) analysis to extract small but critical datasets, followed by the development of distributed lightweight AI models, and the use of digital twins(DTs) to create precise replicas of physical 6G networks. This leads to a pervasive multi-level(PML)-AI framework supported by a task-centric, three-layer 6G architecture. The AI framework operates through non-real-time and real-time cycles, leveraging three key technologies: wireless data KGs for efficient data management,lightweight AI mode

关键词： artificial intelligence sustainable 6G green real-time controllable

基于关键驱动力的怒江州兰坪县泥石流危险性评价

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云南大学学报（自然科学版） 2015年第2期37卷 240-249页

作者：徐慧娟黄江成云南大学国际河流与生态安全研究院云南省国际河流与生态安全重点实验室云南昆明650091

近年来,云南怒江地区多次暴发大规模灾害性泥石流,造成了重大人员伤亡和财产损失.文章选取矿产和水电资源丰富的兰坪县泥石流为研究对象,通过现场勘察,结合已有调查成果,明晰兰坪县泥石流空间分布格局;在此基础上,从地质驱动力、水动力... 详细信息

近年来,云南怒江地区多次暴发大规模灾害性泥石流,造成了重大人员伤亡和财产损失.文章选取矿产和水电资源丰富的兰坪县泥石流为研究对象,通过现场勘察,结合已有调查成果,明晰兰坪县泥石流空间分布格局;在此基础上,从地质驱动力、水动力和重力驱动力3方面构建基于关键驱动力的单沟泥石流危险性评价指标体系,运用层次分析法与GIS技术开展危险性评价.结果显示:兰坪县境内79条泥石流沟中,处于高危险性的有20条,中危险性30条,澜沧江右岸和左岸分别为高危险性和中危险性泥石流沟的集中区.进一步分析表明,兰坪县泥石流危险性高低受降水影响较大,从澜沧江右岸到左岸再到通甸河,降水逐渐减少,泥石流的危险性也逐渐降低;本研究结果可对兰坪县大型工程建设及保障运营安全等具有一定的指导意义.

关键词：怒江地区泥石流危险性评价澜沧江中游

白肋烟不同品种香气前体物降解产物及品质的研究

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湖南农业大学学报（自然科学版） 2006年第2期32卷 149-153页

作者：柴家荣黄成江云南省烟草科学研究所云南玉溪653100

采用同时蒸馏萃取、顶空分离前处理方法及气相色谱—质谱联用分析鉴定技术,对TN90,KY907,KY908,K26,TN86,KY8959等6个白肋烟品种的香气前体物降解产物进行了研究.结果表明,品种间香气前体物分解转化的产物成分含量差异较明显,含量差异... 详细信息

采用同时蒸馏萃取、顶空分离前处理方法及气相色谱—质谱联用分析鉴定技术,对TN90,KY907,KY908,K26,TN86,KY8959等6个白肋烟品种的香气前体物降解产物进行了研究.结果表明,品种间香气前体物分解转化的产物成分含量差异较明显,含量差异大于成分种类差异;不同含量的关键香气物质成分相同.综合各品种香气物成分含量及评吸结果,烟叶品质TN90最好,TN86和KY907次之,KY8959与KY908第三,K26较差.

关键词：白肋烟香气前体物品种烟叶品质