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2-Pyridinylmethyl borrowing:base-promoted C-alkylation of(pyridin-2-yl)-methyl alcohols with ketones via cleavage of unstrained C(sp^(3))-C(sp^(3))bonds

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Organic Chemistry Frontiers 2022年第2期9卷 299-304页

作者： Chuan-Ming Hong fei-fei Zou Xin Zhuang Zhen Luo Zheng-Qiang Liu Li-qing Ren qing-Hua Li Tang-Lin Liu School of Chemistry and Chemical Engineering Southwest UniversityChongqing 400715China

A transition metal-free synthesis of β-(pyridin-2-yl)-methyl ketones,using(pyridin-2-yl)methyl alcohols and ketones through the 2-pyridinylmethyl borrowing strategy,has been *** approach provides an efficient,available and environmentally benign access,leading to alkylation products with broad functional group tolerance and excellent ***,the selective cleavage of unactivated C(sp^(3))-C(sp^(3))bonds of common secondary alcohols was achieved with high atom economy.

关键词： alcohols bonds cleavage

Inverse scattering transforms of the inhomogeneous fifth-order nonlinear Schrodinger equation with zero/nonzero boundary conditions

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Communications in Theoretical Physics 2022年第8期74卷 56-68页

作者： jin-jin Mao Shou-Fu Tian Tian-Zhou Xu Lin-fei Shi School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100081China School of Mathematics China University of Mining and TechnologyXuzhou 221116China

The present work studies the inverse scattering transforms(IST)of the inhomogeneous fifth-order nonlinear Schrodinger(NLS)equation with zero boundary conditions(ZBCs)and nonzero boundary conditions(NZBCs).Firstly,the bound-state solitons of the inhomogeneous fifth-order NLS equation with ZBCs are derived by the residue theorem and the Laurent's series for the first ***,by combining with the robust IST,the Riemann-Hilbert(RH)problem of the inhomogeneous fifth-order NLS equation with NZBCs is ***,based on the resulting RH problem,some new rogue wave solutions of the inhomogeneous fifth-order NLS equation are found by the Darboux ***,some corresponding graphs are given by selecting appropriate parameters to further analyze the unreported dynamic characteristics of the corresponding solutions.

关键词： the inhomogeneous fifth-order nonlinear Schrodinger equation inverse scattering transforms Darboux transformation bound-state soliton rogue wave zero/nonzero boundary conditions

Multi-objective model and optimization algorithm based on column generation for continuous casting production planning

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Journal of Iron and Steel Research International 2019年第3期26卷 242-250页

作者： Jian Yi Shu-jin Jia Bin Du qing Liu Institute of Intelligent Manufacturing Baosteel Central Research Institute Shanghai 201900 China College of Information Science and Engineering Northeastern UniversityShenyang 110819 LiaoningChina State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China

The optimization of continuous casting production planning(CCPP)in the steel industry was *** essence of CCPP is the productive capability balance of back-end facilities over the planning time *** facilities with the demands of productive capability are called the *** the basis of charge plans,the task of CCPP is to produce cast plans according to the rules of cast design in order to meet the ***,a multi-objective model was established with considering the demands of flows,the capability requirements of liquid steel refini ng devices,and the rules of cast ***,the model was decomposed into a master problem(set partitioning problem model)and a series of subproblem(pricing problem model)by using Dantzig-Wolfe decomposition ***,a column generation-based optimization algorithm(CGBOA)was *** experimental results on practical production data from Baosteel demonstrate that the proposed algorithm is effective and ***,a new decision support system based on CGBOA has been successfully established and applied to No.2 Steelmaking Plant at Baosteel.

关键词： Steelmaking Continuous casting Production planning Charge Cast Column generation

Global trends and hotspots of treatment for nonalcoholic fatty liver disease:A bibliometric and visualization analysis(2010-2023)

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World Journal of Gastroenterology 2023年第37期29卷 5339-5360页

作者： jin-jin Dai Ya-fei Zhang Zhen-Hua Zhang Department of Infectious Diseases Suzhou Hospital of Anhui Medical UniversitySuzhou 234000Anhui ProvinceChina Department of Infectious Diseases The Second Affiliated Hospital of Anhui Medical UniversityHefei 230601Anhui ProvinceChina

BACKGROUND Nonalcoholic fatty liver disease(NAFLD)is chronic,with its progression leading to liver fibrosis and end-stage *** NAFLD is increasingly common,no treatment guideline has been *** mechanistic studies and drug trials have been conducted for new drug development to treat *** up-to-date overview on the knowledge structure of NAFLD through bibliometrics,focusing on research hotspots,is necessary to reveal the rational and timely directions of development in this *** To research the latest literature and determine the current trends in treatment for *** Publications related to treatment for NAFLD were searched on the Web of Science Core Collection database,from 2010 to ***,CiteSpace,and R package“bibliometrix”were used to conduct this bibliometric *** key information was extracted,and the results of the cluster analysis were based on network data for generating and investigating maps for country,institution,journal,and *** analysis,bursts and cluster analysis,cooccurrence analysis,and trend topic revealed the knowledge structure and research hotspots in this *** Prism 9.***.1.733 and Microsoft Office Excel 2019 were used for data analysis and *** In total,10829 articles from 120 countries(led by China and the United States)and 8785 institutions were *** number of publications related to treatment for NAFLD increased *** China produced the most publications,the United States was the most cited country,and the United Kingdom collaborated the most from an international *** University of California-San Diego,Shanghai Jiao Tong University,and Shanghai University of Traditional Chinese Medicine produced the most publications of all the research *** International Journal of Molecular Sciences was the most frequent journal out of the 1523 total journals,and Hepatology was the most cited and co-cited ***

关键词： Bibliometrics Treatment Therapy Nonalcoholic fatty liver disease Metabolic dysfunction-associated fatty liver disease Historiography analysis

Direct electrochemical reduction of solid vanadium oxide to metal vanadium at low temperature in molten CaCl_2-NaCl

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International Journal of Minerals,Metallurgy and Materials 2012年第6期19卷 499-505页

作者： Zhuo-fei Cai Zhi-mei Zhang Zhan-cheng Guo Hui-qing Tang State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China

V205 sintered pellets and graphite rods were employed as the cathode and the anode, respectively; a molten CaC12-NaCI salt was used as the electrolyte. Then, V205 was directly reduced to metal vanadium by the Fray-Farthing-Chen （FFC） method at 873 K to realize low-temperature electrolysis. Two typical experimental conditions, electrolysis time and voltage, were taken into account to investigate the current efficiency and remaining oxygen content in electrolyzed products. The composition and microstmcture of the products were charac- terized by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. SEM observations show that a higher voltage （1.8-3.4 V） and a longer electrolysis time （2-5 h） can improve the product quality separately, that is, a lower remaining oxygen content and a more uniform microstructure. The products with an oxygen content of 0.205wt% are successfully obtained below 3.4 V for 10 h. However, the current effi- ciency is low, and further work is required.

关键词： vanadium metallurgy vanadium pentoxide direct reduction electrolysis

Maps Preserving Peripheral Spectrum of Generalized Jordan Products of Operators

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Acta Mathematica Sinica,English Series 2015年第6期31卷 953-972页

作者： Wen ZHANG jin Chuan HOU Xiao fei QI Department of Mathematics Shanxi University Department of Mathematics University of TechnologyTaiyuan

Let X1 and X2 be complex Banach spaces with dimension at least three, A1 and A2 be standard operator algebras on X1 and X2, respectively. For k ≥ 2, let （i1, i2, . . . , im） be a finite sequence such that {i1, i2, . . . , im} = {1, 2, . . . , k} and assume that at least one of the terms in （i1, . . . , im） appears exactly once. Define the generalized Jordan productT1 o T2 o··· o Tk = Ti1Ti2··· Tim ＋ Tim··· Ti2Ti1 on elements in Ai. This includes the usual Jordan product A1A2 ＋ A2A1, and the Jordan triple A1A2A3 ＋ A3A2A1. Let Φ ： A1 → A2 be a map with range containing all operators of rank at most three. It is shown that Φ satisfies that σπ（Φ（A1） o··· o Φ（Ak）） = σπ（A1 o··· o Ak） for all A1, . . . , Ak, where σπ（A） stands for the peripheral spectrum of A, if and only if Φ is a Jordan isomorphism multiplied by an m-th root of unity.

关键词： Peripheral spectrum generalized Jordan products Banach spaces standard operatoralgebras

Experimental Investigation of Local Scour Around A New Pile-Group Foundation for Offshore Wind Turbines in Bi-Directional Current

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China Ocean Engineering 2018年第6期32卷 737-745页

作者： JI Chao ZHANG jin-feng ZHANG qing-he LI Ming-xing CHEN Tong-qing State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Fourth Harbor Engineering Investigation and Design Institute Co. Ltd. China Communications Construction Company

The local scour around a new pile-group foundation of offshore wind turbine subjected to a bi-directional current was physically modeled with a bi-directional flow flume. In a series of experiments, the flow velocity and topography of the seabed were measured based on a system composed of plane positioning equipment and an *** results indicate that the development of the scour hole was fast at the beginning, but then the scour rate decreased until reaching equilibrium. Erosion would occur around each pile of the foundation. In most cases, the scour pits were connected in pairs and the outside widths of the scour holes were larger than the inner widths. The maximum scour depth occurred at the side pile of the foundation for each test. In addition, a preliminary investigation shows that the larger the flow velocity, the larger the scour hole dimensions but the shorter equilibrium time. The field maximum scour depth around the foundation was obtained based on the physical experiments with the geometric length scales of 1:27.0, 1:42.5 and 1:68.0, and it agrees with the scour depth estimated by the HEC-18 equation.

关键词： offshore wind turbines new pile-group foundation local scour bi-directional current

Effects of organic matter and salinity on the flocculation of kaolinites in a settling column

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Journal of Hydrodynamics 2021年第1期33卷 150-156页

作者： Zhong-yue Li jin-feng Zhang qing-he Zhang Xiao-teng Shen Tong-qing Chen State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China Key Laboratory of Earthquake Engineering Simulation and Seismic Resilience of China Earthquake Administration Tianjin UniversityTianjin 300350China Key Laboratory of Ministry of Education for Coastal Disaster and Protection Hohai UniversityNanjing 210098China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing 210029China

The flocculation and the settling of the cohesive sediment play an important role in the sediment transport process,and they are affected by many *** the coasts and in the estuaries,the organic matter and the salinity are two significant *** this study,experiments are carried out to evaluate the flocculation and the settling of the kaolinite in cases of various organic matter and salinity solutions in quiescent *** optical multi-channel suspended concentration monitoring system is used to measure the sediment concentration and the floc *** results show that the settling velocity decreases with the increase of the organic matter content,and the floc size increases with the increase of the organic matter *** addition,an empirical formula for the settling velocity under the influence of the organic matter and the salinity based on the experimental results is proposed.

关键词： Kaolinite humic acid salinity settling velocity floc size distribution

Reliable Control for Nonlinear Systems with Stochastic Actuators Fault and Random Delays Through a T-S Fuzzy Model Approach

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Acta Mathematicae Applicatae Sinica 2016年第2期32卷 395-406页

作者： jin-liang LIU Zhou GU Shu-min fei School of Automation Southeast University College of Information Engineering Nanjing University of Finance and Economics

This paper considers the reliable control design for T-S fuzzy systems with probabilistic actuators faults and random time-varying delays. The faults of each actuator occurs randomly and its failure rates are governed by a set of unrelated random variables satisfying certain probabilistic distribution. In terms of the probabilistic failures of each actuator and time-varying random delays, new fault model is proposed. Based on the new fuzzy model, reliable controller is designed and sufficient conditions for the exponentially mean square stability （EMSS） of T-S fuzzy systems are derived by using Lyapunov functional method and linear matrix inequality （LMI） technique. It should be noted that the obtained criteria depend on not only the size of the delay, but also the probability distribution of it. Finally, a numerical example is given to show the effectiveness of the proposed method.

关键词： reliable control fuzzy system probabilistic failures random delays