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Behavioural analysis and dynamic simulation of the debris flow that occurred in Ganluo County(Sichuan, China) on 30 August 2020

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Journal of Mountain Science 2022年第6期19卷 1495-1508页

作者： LI Nuo-dong LIU Wei ZHAO jin-heng Chengdu Power Supply Company of State Grid Sichuan Electric Power Company Chengdu 610041China Key Laboratory of Mountain Hazards and Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu 610065China Department of Water Hydropower and Construction Engineering Skill Training Center of State Grid Sichuan Electric Power CompanyChengdu 610000China

On August 30, 2020, a high-intensity storm that dropped 45.4 mm of rain in 5 hours hit the Heixiluo basin and triggered a landslide-generated debris flow event, causing fatalities and damage. The original source of the debris flow was a large slope collapse on a steep hillside. The fallen debris mass was enlarged through sediment entrainment and slope collapse and ultimately buried a bridge at the gully entrance. Approximately 6.9×10;m;of material, including sediments and collapsed slope deposits in the gullies, was entrained, and the maximum erosion depth reached 17 m. A geomorphological analysis was initially performed based on a detailed field investigation to recognize the liquid and solid sources of the debris flow and the areas subjected to deposition and erosion. A map of the erosiondeposition distribution was obtained based on preand post-event DEMs. Using the rainfall estimated by the nearest rain gauge and the solid source estimated by the DEMs, runoff and debris flow propagation was simulated using a liquid-solid two-phase model that considers the effects of runoff and entrainment. The similarity between the estimated and simulated deposition-erosion volumes was satisfactory. The behaviour of debris flows captured in the simulation is broadly in line with the main features of the observed event.

关键词： Debris flow Formation analysis Two-phase model Dynamic simulation

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Numerical Analysis of the Flow Field in a Sloshing Tank with a Horizontal Perforated Plate

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Journal of Ocean University of China 2017年第4期16卷 575-584页

作者： jin heng LIU Yong LI Huajun FU Qiang Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100P.R.China CIMC Offshore Institute Co.Ltd. Yantai 264670P R.China

Liquid sloshing is a type of free surface flow inside a partially filled water *** exerts a significant effect on the safety of liquid transport systems;in particular,it may cause large hydrodynamic loads when the frequency of the tank motion is close to the natural frequency of the *** plates have recently been used to suppress the violent movement of liquids in a sloshing tank at resonant *** this study,a numerical model based on OpenF OAM(Open Source Field Operation and Manipulation),an open source computed fluid dynamic code,is used to investigate resonant sloshing in a swaying tank with a submerged horizontal perforated *** numerical results of the free surface elevations are first verified using experimental data,and then the flow characteristics around the perforated plate and the fluid velocity distribution in the entire tank are examined using numerical *** results clearly show differences in sloshing motions under first-order and third-order resonant *** study provides a better understanding of the energy dissipation mechanism of a horizontal perforated plate in a swaying tank.

关键词： sloshing horizontal perforated plate numerical simulation flow field energy dissipation

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Transformations of N-arylpropiolamides to indoline-2,3-diones and acids via C≡C triple bond oxidative cleavage and C(sp^2)–H functionalization

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Science China Chemistry 2020年第2期63卷 222-227页

作者： Ming-Bo Zhou Yang Li Xuan-Hui Ouyang jin-heng Li Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong UniversityNanchang 330063China Key Laboratory of Chemical Biology&Traditional Chinese Medicine Research(Ministry of Education) Hunan Normal UniversityChangsha 410081China State Key Laboratory of Applied Organic Chemistry Lanzhou University'Lanzhou 730000China

A new palladium-catalyzed oxidative conversion of N-arylpropiolamides and H2O to various indoline-2,3-diones and acids through the C≡C triple bond cleavage and C(sp2)–H functionalization is described,which is promoted by a cooperative action of catalytic CuBr2,2,2,6,6-tetramethyl-1-piperidinyloxy(TEMPO)and *** method provides a practical tool for transformations of alkynes by means of a C–H functionalization strategy,which enables the formation of one C–C bond and multiple C–O bonds in a single reaction with high substrates compatibility and excellent functional group tolerance.

关键词： alkynes indoline-2,3-diones acids C≡C bond oxidative cleavage C–H functionalization

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Nickel-Promoted Oxidative ipso-Annulation ofN-（p-Methoxyaryl）propiolamides with a-Carbonyl Alkyl Bromides

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Chinese Journal of Chemistry 2017年第3期35卷 299-302页

作者： Meng Li Ren-Jie Song jin-heng Li Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong University Nanchang Jiangxi 330063 China State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan University Changsha Hunan 410082 China

A new route to producing 3-alkyl spiro[4,5]trienones via nickel-promoted radical oxidative ipso-annulation of N-(p-methoxyaryl)propiolamides with α-carbonyl alkyl bromides using TBHP oxidant is described. The method allows the formation of three new C—C bonds through a sequence of oxidative C—Br bond cleavage, ipso-cyclization and dearomatization, and represents a new alkyne 1,2-difunctionalization to access to the construction of spiro[4,5]trienones.

关键词： nickel radical ipso-annulation alkynes 3-alkyl spiro[4 5]trienones

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An adaptive graph embedding method for feature extraction of hyperspectral images based on approximate NMR model

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Optoelectronics Letters 2023年第7期19卷 443-448页

作者： QIU Hong WANG Renfang jin heng WANG Feng College of Big Data and Software Engineering Zhejiang Wanli UniversityNingbo 315200China College of Information Shanghai Ocean UniversityShanghai 200120China

This paper introduces an approximate nuclear norm based matrix regression projection(ANMRP) model,an adaptive graph embedding method,for feature extraction of hyperspectral *** ANMRP utilizes an approximate NMR model to construct an adaptive neighborhood map between *** globally optimal weight matrix is obtained by optimizing the approximate NMR model using fast alternating direction method of multipliers(ADMM).The optimal projection matrix is then determined by maximizing the ratio of the local scatter matrix to the total scatter matrix,allowing for the extraction of discriminative *** results demonstrate the effectiveness of ANMRP compared to related methods.

关键词： approximate embedding matrix

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Cu(OAc)_2 catalyzed Sonogashira cross-coupling reaction in amines

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Chinese Chemical Letters 2007年第1期18卷 13-16页

作者： Sheng Mei Guo Chen Liang Deng jin heng Li Key Laboratory of Chemical Biology ＆ Traditional Chinese Medicine Research （Ministry of Education） College of Chemistry and Chemical Engineering Hunan Normal University Changsha 410081 China

A simple Cu（OAc）2 catalyzed Sonogashira coupling protocol is presented. It was found that the couplings of a variety of aryl halides with terminal alkynes were conducted smoothly to afford the corresponding desired ... 详细信息

关键词： Cu(OAc)2 Sonogashira cross-coupling reaction Aryl halide Alkyne

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Palladium-Catalyzed Oxidative C=C Triple Bond Cleavage of 2-Alkynyl Carbonyl Compounds Toward 1,2-Dicarbonyl Compounds

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Chinese Journal of Chemistry 2020年第6期38卷 553-558页

作者： Ming-Bo Zhou Mu-Jia Luo Ming Hu jin-heng Li Key Laboratory of Chemical Biology&Traditional Chinese Medicine Research(Ministry of Education) Hunan Normal UniversityChangshaHunan 410081China Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong UniversityNanchangJiangxi 330063China State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan UniversityChangshaHunan 410082China

A new,gen era I palladium-catalyzed oxidative strategy for the cleavage of the C=C triple bond is *** employing PdCI2/CuBr2/TEMPO and air as the catalytic system and H2O as the carbonyl oxygen atom source,a wide range of 2-alkynyl carbonyl compounds,including 1,3-disubstituted prop-2-yn-l-ones,propiolamides and propiolates,lost an alkynyl carbon to access various 1,2-dicarbonyl compounds,e.g.,1,2-diones,2-keto amides and 2-keto esters,through Wacker oxidation,intramolecular cyclization and C—C bond cleavage cascades.

关键词： 1,2 carbonyl cleavage

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Recent advances in radical-mediated [2+2+m] annulation of 1,n-enynes

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Science China Chemistry 2019年第11期62卷 1463-1475页

作者： Chong-Hui Xu Yang Li jin-heng Li Jian-Nan Xiang Wei Deng State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong UniversityNanchang 330063China

1,n-Enynes are a versatile class of unsaturated hydrocarbons that found broad applications in the synthetic community of natural products,biologically active structures and functional *** methods for the transformations of 1,n-enynes include the radical-mediated[2+2+m]annulation reaction as they are particularly efficient accesses to functionalized polycyclic *** herein highlighted recent process in the radical-mediated[2+2+m]annulation of 1,n-enynes,including[2+2+1]and[2+2+2]modes,for the construction of five-to six-membered-ring-fused polycyclic ***,the mechanisms for these transformations were described.

关键词： radical annulation oxidants 1 n-enynes polycycles

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Light-induced magnetic phase transition in van der Waals antiferromagnets

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Science China(Physics,Mechanics & Astronomy) 2023年第7期66卷 136-141页

作者： Jiabin Chen Yang Li Hongyu Yu Yali Yang heng jin Bing Huang Hongjun Xiang Key Laboratory of Computational Physical Sciences(Ministry of Education) Institute of Computational Physical SciencesState Key Laboratory of Surface PhysicsDepartment of PhysicsFudan UniversityShanghai 200433China Shanghai Qi Zhi Institute Shanghai 200030China Beijing Computational Science Research Center Beijing 100193China Department of Physics Beijing Normal UniversityBeijing 100193China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China

Control over magnetic properties by optical stimulation is not only interesting from the physics point of view,but also important for practical applications such as magneto-optical ***,based on a simple tight-binding(TB)model,we propose a general theory of light-induced magnetic phase transition(MPT)in *** the fact that the bandgap of the antiferromagnetic(AFM)phase is usually larger than that of the ferromagnetic(FM)one for a given system,we suggest that light-induced electronic excitation prefers to stabilize the FM state over the AFM one,and will induce an MPT from AFM phase to FM phase once a critical photocarrier concentration(αc)is *** theory has been confirmed by performing firstprinciples calculations on a series of 2D van der Waals(vd W)***,a linear relationship betweenαc and the intrinsic material parameters is obtained,in agreement with our TB model *** general theory paves a new way to manipulate 2D magnetism with high speed and superior resolution.

关键词： first-principles calculation density functional theory two-dimensional materials magnetic phase transition

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Cyclic electron flow around photosystem I is required for adaptation to high temperature in a subtropical forest tree, Ficus concinna

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第10期10卷 784-790页

作者： Song-heng jin Xue-qin LI Jun-yan HU Jun-gang WANG School of Forestry and Biotechnology Zhejiang Forestry University Lin'an 311300 China Tianmu College Zhejiang Forestry University Lin'an 311300 China

Dissipation mechanisms of excess photon energy under high-temperature stress were studied in a subtropical forest tree seedling, Ficus concinna. Net CO2 assimilation rate decreased to 16% of the control after 20 d high-temperature stress, and thus the absorption of photon energy exceeded the energy required for CO2 assimilation. The efficiency of excitation energy capture by open photosystem Ⅱ（PSⅡ） reaction centres （Fv＇/Fm＇） at moderate irradiance, photochemical quenching （qp）, and the quantum yield of PSII electron transport （φPSⅡ） were significantly lower after high-temperature stress. Nevertheless, non-photochemical quenching （qNP） and energy-dependent quenching （qE） were significantly higher under such conditions. The post-irradiation transient of chlorophyll （Chl） fluorescence significantly increased after the turnoff of the actinic light （AL）, and this increase was considerably higher in the 39 ℃-grown seedlings than in the 30 ~C-grown ones. The increased post-irradiation fluorescence points to enhanced cyclic electron transport around PSI under high growth temperature conditions, thus helping to dissipate excess photon energy non-radiatively.

关键词： Ficus concinna High-temperature stress Chlorophyll fluorescence Photosynthesis Cyclic electron transport around photosystem I Dissipation of excitation energy

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