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Numerical Analysis of Emergency River Restoration Scheme for Qingping Mega Debris Flow

Journal of Mountain Science 2013年第1期10卷 130-136页

作者： CHEN Ri-dong LIU Xing-nian HUANG Er guo zhi-xue State Key Laboratory of Hydroscience and Engineering Tsinghua University State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University

The mega debris flow occurred on August 13 th 2010 in Qingping town,China(hereafter called '8.13' Debris Flow) have done great damage to the local habitants as well as to the re-construction projects in the quake-hit areas,and the channel-fill deposit problem caused by the debris flow was the most ***,it is of high possibility that an even severe deposit problem would reappear and result in worse *** order to maximize risk reduction of this problem,relevant departments of the government established a series of emergency river restoration schemes,for which the numerical analysis is an important procedure to evaluate and determine the optimized *** study presents a numerical analysis by applying a twodimensional debris flow model combined with a relevant water-sediment model to simulate the deposit during the progress of the debris flow,and to calculate and analyze the river flow field under both the present condition and different restoration *** results show that the debris flow model,which takes the confluence of the Wenjia Gully to the main river into account,could simulate the deposit process quite *** the reproduced debris flow from the simulation of the '8.13' Debris Flow,the original river flow path has switched to a relatively lower place just along the right bank with a high speed of near 7m.s-1 after being blocked by the deposit,which is highly *** prevent this hazard,a recommended scheme is derived through inter-comparison of different restoration *** shows that the recommended scheme is able to reduce the water level and as well to regulate the flow *** on the given conditions of the mainstream and the tributary confluence for the simulated '8.13' Debris Flow,when encountering a debris flow with deposit volume less than 0.5 million m3,the river channel can endure a 20-year return flood;however,when the deposit volume increases to 2 million m3,the flood capacity of the river will be

关键词： Flash flood Debris flow River restoration Numerical analysis Finite element method

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High-Performance Recyclable Furan-based Epoxy Resin and Its Carbon Fiber Composites with Dense Hydrogen Bonding

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Chinese Journal of Polymer Science 2024年第1期42卷 73-86,I0008页

作者： Chang-Bo Zhao Lu-Kun Feng Hui Xie Ming-Liang Wang Bing guo zhi-Yong xue Cai-Zhen Zhu Jian Xu Advanced Materials Research Institute North China Electric Power UniversityBejing 102206China Institute of Low-Dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China School of Science and Shenzhen Key Laboratory of Flexible Printed Electronics Technology and Shenzhen Key Laboratory of Advanced Functional Carbon Materials Research and Comprehensive ApplicationHarbin Institute of TechnologyShenzhen 518055China

The emerging biomass-based epoxy vitrimers hold great potential to fulfill the requirements for sustainable development of *** the existence of dynamic chemical bonds in vitrimers often reduces both the thermal and mechanical properties of epoxy resins, it is challenging to produce recyclable epoxy vitrimers with both excellent mechanical properties and good thermal stability. Herein, a monomer 4-(((5-(hydroxymethyl)furan-2-yl)methylene)amino)phenol(FCN) containing furan ring with potential to form high density of hydrogen bonding among repeating units is designed and copolymerized with glycerol triglycidyl ether to yield epoxy resin(FCN-GTE), which intrinsically has dual hydrogen bond networks, dynamic imine structure and resultant high performance. Importantly, as compared to the BPA-GTE, the FCN-GTE exhibits significantly improved mechanical properties owing to the increased density of hydrogen bond network and physical crosslinking interaction. Furthermore, density functional theory(DFT) calculation and in situ FTIR analysis is conducted to decipher the formation mechanism of hydrogen bond network. In addition, the FCN-GTE possesses superior UV shielding, chemical degradation, and recyclability because of the existence of abundant imine bonds. Notably, the FCN-GTE-based carbon fiber composites could be completely recycled in an amine *** study provides a facile strategy for synthesizing recyclable biomass-based high-performance epoxy vitrimers and carbon fiber composites.

关键词： Furan Hydrogen bond network Dynamic Schiff base Carbon fiber composites Recycling

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Dry eye disease in systemic lupus erythematosus: a cross sectional study

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1255-1261页

作者： Sui-Fang Kang Ying-xue Wang Qi-Chen Zhang zhi-Lun Wang guo-Ling Chen Department of Ophthalmology the Second Hospital of Shandong UniversityJinan 250033Shandong ProvinceChina Department of Rheumatology the Second Hospital of Shandong UniversityJinan 250033Shandong ProvinceChina

AIM:To explore ocular surface manifestations of dry eye disease(DED)and its influencing factors in systemic lupus erythematosus(SLE)***:Ophthalmological examinations were conducted in SLE patients(n=43)and controls(n=41),including Ocular Surface Disease Index(OSDI),objective scatter index(OSI),tear meniscus height(TMH),lipid layer thickness(LLT),non-invasive Keratograph tear breakup time(NIKBUT),corneal fluorescein score(CFS),Schirmer I *** was diagnosed according to the Tear Film and Ocular Surface Society Dry Eye Workshop II *** patients were further divided into DED group and non-DED group,the disease activity,clinical manifestations and laboratory investigations were compared between the two *** disease activity was evaluated by Systemic Lupus Erythematosus Disease Activity Index 2000(SLEDAI-2K).Receiver operative characteristic(ROC)curve and multiplefactor binary logistic regression were ***:SLE patients showed higher OSDI[9.1(2.8-15.9)vs 6.3(2.2-7.5),P=0.035],higher OSI[1.67(1.09-2.60)vs 0.96(0.87-1.60),P=0.001],higher CFS[1(0-2)vs 0(0-1),P=0.001],lower LLT[65(42-100)vs 100(79.5-100),P=0.010],and lower NIKBUT[8.03(4.02-9.73)vs 9.67(5.26-12.71),P=0.030]than *** 32.6%of SLE patients had DED,which was higher than 12.2%of healthy *** group showed higher SLEDAI-2K score[9.7±6.1 vs 5.4±3.4,P=0.025],higher anti-cardiolipin antibody(ACL)[8.7(3.5-13.2)vs 3.6(2.0-6.9),P=0.035],and higher proportion of patients with cutaneous eruption[42.9%vs 6.9%,P=0.015]than non-DED *** to multiple-factor binary logistic regression analysis,the SLEDAI-2K score(OR=1.194,P=0.041)and cutaneous eruption(OR=7.094,P=0.045)could be consider as risk factors for DED in SLE *** ROC curve of the combined factors including age,disease duration,SLEDAI-2K score,ACL,and cutaneous eruption was analyzed,with a sensitivity of 0.786,a specificity of 0.793,and an area under curve of ***:Ocular surface affec

关键词： autoimmune disease systemic lupus erythematosus dry eye disease

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A Local Tb Theorem for Square Functions and Parabolic Layer Potentials

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1941-1966页

作者： zhi Dan WANG guo Ming ZHANG School of Physical and Mathematical Sciences Nanjing Tech UniversityNanjing 211816P.R.China Frontiers Science Center for Nonlinear Expectations Ministry of EductionResearch Center for Mathematics and Interdisciplinary SciencesShandong UniversityQingdao266237P.R.China

In this paper,we give a locally parabolic version of Tb theorem for a class of vector-valued operators with off-diagonal decay in L^(2) and certain quasi-orthogonality on a subspace of L^(2),in which the testing functions themselves are also *** an application,we establish the boundedness of layer potentials related to parabolic operators in divergence form,defined in the upper half-space Rn+2+:={(x,t,λ)∈R^(n+1)×(0,∞)},with uniformly complex elliptic,L^(∞),t,λ-independent coefficients,and satisfying the De Giorgi/Nash estimates.

关键词： Local Tb theorems Calderon-Littlewood-Paley family Parabolic layer potentials Carleson measure estimates

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Resonance mechanism of flapping wing based on fluid structure interaction simulation

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Chinese Journal of Aeronautics 2024年第5期37卷 243-262页

作者： Yueyang guo Wenqing YANG Yuanbo DONG Dong xue National Key Laboratory of Science and Technology on Aerodynamic Design and Research School of AeronauticsNorthwestern Polytechnical UniversityXi'an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063China Yangtze River Delta Research Institute of Northwestern Polytechnical University Taicang 215400China

Certain insect species have been observed to exploit the resonance mechanism of their *** order to achieve resonance and optimize aerodynamic performance,the conventional approach is to set the flapping frequency of flexible wings based on the Traditional Structural Modal(TSM)***,there exists controversy among researchers regarding the relationship between frequency and aerodynamic *** that the structural response of wings can be influenced by the surrounding air vibrations,an analysis known as Acoustic Structure Interaction Modal(ASIM)is introduced to calculate the resonant *** this study,Fluid Structure Interaction(FSI)simulations are employed to investigate the aerodynamic performance of flapping wings at modal frequencies derived from both TSM and ASIM *** performance is evaluated for various mass ratios and frequency ratios,and the findings indicate that the deformation and changes in vortex structure exhibit similarities at mass ratios that yield the highest aerodynamic ***,the flapping frequency associated with the maximum time-averaged vertical force coefficient at each mass ratio closely aligns with the ASIM frequency,as does the frequency corresponding to maximum ***,the ASIM analysis can provide an effective means for predicting the optimal flapping frequency for flexible ***,it enables the prediction that flexible wings with varying mass ratios will exhibit similar deformation and vortex structure *** paper offers a fresh perspective on the ongoing debate concerning the resonance mechanism of Flexible Flapping Wings(FFWs)and proposes an effective methodology for predicting their aerodynamic performance.

关键词： Flexible Flapping Wing(FFW) Acoustic Structure Interaction Modal(ASIM) Fluid Structure Interaction(FSI) Resonance mechanism Aerodynamic performance

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Side-Chain Engineering of Non-Fullerene Acceptors with Trialkylsilyloxy Groups for Enhanced Photovoltaic Performancet

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Chinese Journal of Chemistry 2024年第18期42卷 2153-2160页

作者： Qingyuan Wang Qi Chen Shixin Meng Li Tian Haiqiao Wang Yu Chen Zitong Liu Lingwei xue zhi-guo Zhang State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijingUniversityof Chemical TechnologyBeijing 100029China School of Materials Science and Engineering Henan University of TechnologyZhengzhouHenan 450001China Beijing Engineering Research Center for the Synthesis and Applications of Waterborne Polymers Beijing University of Chemical TechnologyBeijing100029China The Institute of High Energy Physics Chinese Academy of SciencesBejing 100049China state Key Laboratory of Applied Organic Chemistry(SKLAoc) College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhouGansu730000China Yaoshan Laboratory Pingdingshan UniversityPingdingshanHenan 467000China

Side-chain engineering has emerged as a highly effective strategy for tailoring the aggregation behavior and charge transport properties of non-fullerene small molecule acceptors(SMAs).In this study,we designed and synthesized two SMAs,namely BTPSi-Bu and BTPSi-Pr,respectively incorporating tributylsilyloxy and trisopropylsilyloxy groups in their outer ***,BTPSi-Bu exhibited better planarity,crystallization,and favorable phase separation when paired with PM6 donor polymer compared to its counterpart,*** resulting organic solar cells,utilizing the PM6:BTPSi-Bu blend,demonstrated a remarkable power conversion efficiency of 17.41%and a high open-circuit voltage of 0.859 *** findings underscore the significance of integrating trialkylsilyloxy side chains into SMAs as a rational design approach for enhancing the performance of photovoltaic systems.

关键词： Organic solar cells Non-fullerene acceptors Oligomers Side-chain engineering Energy conversion Synthesis design Donor-acceptor systems

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Exploring a new path of green and efficient utilization of sinter return fine to produce composite pellets

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Journal of Iron and Steel Research International 2024年第7期31卷 1610-1622页

作者： Yan-biao Chen Wen-guo Liu Hao guo Jing-song Wang Qing-guo xue Hai-bin Zuo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China MCC Capital Engineering and Research Incorporation Limited Beijing 100176China

Efficient utilization of sinter return fine is an important measure to reduce cost,increase efficiency,save energy and reduce emission.A new path of green and efficient utilization of return fine was proposed to produce composite *** metallurgical properties of composite pellets under the condition of hydrogen-rich blast furnace were *** experimental results indicate that the coated concentrate was consolidated for the composite pellets through normal Fe_(2)O_(3) *** the surface of core return fine,the liquid phase formed due to its low-melting point,assimilated the adjacent concentrate,and then consolidated with the temperature *** with regular pellets,the com-pressive strength and reduction swelling index of composite pellets were decreased,but the reducibility index and softening-melting properties were *** addition,the reduction degradation index of composite pellets was sig-nificantly higher than that of ***,adding composite pellets was conducive to indirect reduction in blast furnace,reducing fuel ratio and improving production *** to the effect of the roasting system on the metallurgical properties,the roasting temperature and time were determined as 1250℃and 30 min,*** composite pellets can be produced under the traditional pelletizing process.

关键词： Sinter Return fine Composite pellet Roasting system Metallurgical property Hydrogen-rich blast furnace

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水库下游清水冲刷影响下的河道调整规律研究

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四川大学学报（工程科学版） 2010年第3期42卷 36-42页

作者：李国志黄良文郭志学双流县水务局四川成都610089 中国水电顾问集团成都勘测设计研究院四川成都610072 四川大学水力学与山区河流开发保护国家重点实验室四川成都610065

水库修建后,改变了河道来水来沙条件,建成初期,由于泥沙被拦截在库内,下泄水流基本为清水,一般会对下游河道造成一定程度的冲刷调整。采用平面2维水沙数学模型研究了大渡河某水电工程修建后,对下游河道的清水冲刷影响,分析了水位、流速... 详细信息

水库修建后,改变了河道来水来沙条件,建成初期,由于泥沙被拦截在库内,下泄水流基本为清水,一般会对下游河道造成一定程度的冲刷调整。采用平面2维水沙数学模型研究了大渡河某水电工程修建后,对下游河道的清水冲刷影响,分析了水位、流速、河床冲淤等参数在常遇洪水作用下的变化。研究表明,清水下泄可以带来下游河道断面形态的调整,河床总体冲刷下切,流速分布趋于均匀,水位明显降低。

关键词：清水冲刷数学模型河床调整流速分布水位

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Effect of slag composition on kinetic behavior of deep deoxidation of 5 wt.% Si high-silicon austenitic stainless steel

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Journal of Iron and Steel Research International 2024年第8期31卷 1873-1885页

作者： Guan-xiong Dou Han-jie guo Jing guo xue-cheng Peng Qing-yun Chen School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing 100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing 100083China

Based on a thermodynamic study of 5 wt.%Si high-silicon austenitic stainless steel(SS-5Si)smelting using CaF_(2)-CaO-Al_(2)0_(3)-Mg-Si0_(2) slag to obtain a low oxygen content of less than 10×10^(-4) wt.%,a kinetic mass transfer model for deep deoxidation was established through laboratory studies,and the effects of slag components and temperature on deoxidation during the slag-steel reaction process of sS-5Si were systematically *** experimental data verified the accuracy of the model *** results showed that the final oxygen content in the steel at 1873 K was mainly controlled by the oxygen content derived from the activity of SiO_(2) regulated by the[Si]-[O]equilibrium reaction in the slag system;in particular,when the slag basicity R(R=w(CaO)/w(SiO2),where w(CaO)and w(SiO_(2))are the contents of CaO and SiO_(2) in the slag,respectively)is 3,the Al2O3 content in the slag needs to be less than 2.7%.The mass transfer rate equation for the kinetics of the deoxidation reaction revealed that the mass transfer of oxygen in the liquid metal is the rate-controlling step under different slag conditions at 1873 K,and the oxygen transfer coefficient ko.m increases with increasing the slag basicity from 4.0×10^(-6)m s^(-1)(R=1)to 4.3×10^(-5) m s^(-1)(R=3).ko.m values at R=2 and R=3 are almost the same,indicating that high slag basicity has little *** integral of the mass transfer rate equation for the deoxidation reaction of SS-5Si under different slag conditions is *** total oxygen content of the molten steel decreases with increasing basicity from an initial content of 22×10^(-4) to 3.2×10^(-4) wt.%(R=3),consistent with the change in ko.m with slag *** R=2,the slag-steel reaction takes 15 min to reach equilibrium(w[O]=5.5×10^(-4) wt.%),whereas at R=3,the slag-steel reaction takes 30 min to reach equilibrium(w[0]=3.2×10^(-4) wt.%).Considering the depth of deoxidation and reaction time of SS-5Si smelting,it is recommended the slag b

关键词： Slag-steel reaction Kinetics Rate-controlling step Deep deoxidation Transfer coefficient

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Target Controllability of Multi-Layer Networks With High-Dimensional Nodes

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 1999-2010页

作者： Lifu Wang Zhaofei Li Ge guo zhi Kong School of Control Engineering Northeastern University at QinhuangdaoQinhuangdao 066004China

This paper studies the target controllability of multilayer complex networked systems,in which the nodes are highdimensional linear time invariant(LTI)dynamical systems,and the network topology is directed and *** influence of inter-layer couplings on the target controllability of multi-layer networks is *** is found that even if there exists a layer which is not target controllable,the entire multi-layer network can still be target controllable due to the inter-layer *** the multi-layer networks with general structure,a necessary and sufficient condition for target controllability is given by establishing the relationship between uncontrollable subspace and output *** the derived condition,it can be found that the system may be target controllable even if it is not state *** this basis,two corollaries are derived,which clarify the relationship between target controllability,state controllability and output *** the multi-layer networks where the inter-layer couplings are directed chains and directed stars,sufficient conditions for target controllability of networked systems are given,*** conditions are easier to verify than the classic criterion.

关键词： High-dimensional nodes inter-layer couplings multi-layer networks target controllability

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