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Palladium-Catalyzed Oxidative Alkynylation of Allenyl Ketones: Access to 3-Alkynyl Poly-substituted Furans

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Chinese Journal of Chemistry 2023年第24期41卷 3598-3604页

作者： Bowen Dou kang wang Jianbo wang Beijing National Laboratory of Molecular Sciences (BNLMS) and Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of ChemistryPeking UniversityBeijing100871 China The State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciences354 Fenglin LuShanghai200032 China

Furans bearing alkynyl substituents are highly useful in organic ***,the methodologies to access these important furan derivatives are rather *** herein report an efficient synthesis of alkynylated furan derivatives based on Pd-catalyzed oxidative cross-coupling reaction between allenyl ketones and terminal *** novel synthesis of alkynylated furans with wide substrate scope is operationally simple and tolerates various functional ***,the formation of the palladium carbene through cycloisomerization and the subsequent alkynyl migratory insertion are proposed as the key steps in the *** reaction reported in this paper further demonstrates the generality of the carbene-based cross coupling.

关键词： Allenyl ketones Oxidative alkynylation Cyclization Isomerization Furans Catalysis Palladium Cross-coupling

Precipitation of α-Fe from Fe_(84-x)Si_(4)B_(12+x)(x=1,3) Amorphous Alloys Under High Magnetic Field Annealing

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Acta Metallurgica Sinica(English Letters) 2021年第8期34卷 1163-1172页

作者： Leipeng Duan kang wang Engang wang Peng Jia Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

This work aims to investigate the effects of high magnetic field annealing(HMFA) on the precipitation of α-Fe from Fe_(84-x)Si_(4)B_(12+ x)( x = 1, 3) amorphous precursors. Isothermal annealing process for Fe_(81)Si_(4)B_(15) and Fe_(83)Si_(4)B_(13) amorphous ribbons has been performed with and without the magnetic field. The magnetic field shows the effects of increasing the nucleation rate and decreasing the grain size of α-Fe crystals simultaneously, during the crystallization processes of the investigated amorphous alloys. By applying HMF, α-Fe crystals with more homogeneous distribution and smaller grain size are achieved in the amorphous matrix, which is crucial helpful to improve the magnetic properties for Fe–Si–B amorphous alloys. The mechanism of HMFA affecting the crystallization microstructure is also discussed in the present work.

关键词： High magnetic field Crystallization α-Fe Nucleation Grain size Atomic diffusion

“Relay-mode”promoting permeation of water-based fire extinguishing agent in granular materials porous media stacks

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Chinese Journal of Chemical Engineering 2022年第7期35卷 98-112页

作者： kang wang Wei Tan Liyan Liu School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Tianjin Key Laboratory of Chemical Process Safety and Equipment Technology Tianjin 300350China

Water-based fire extinguishing agent is the main means to deal with smoldering ***,due to the hydrophobic properties of the particle surface,the porous medium channel provide resistance and slow down the extinguishing agent flow during the downward permeation *** promote the liquid permeation process in such porous media,this work studied liquid imbibition process and analyzed the oscillating and attenuating process of liquid level in capillary channel by theoretical,experimental,and numerical *** empirical mathematical equation was proposed to describe the oscillating process,and the effects of the capillary diameter and contact angle parameters on the transportation process were *** on this,the“relay-mode”was proposed to promote the liquid transportation ***,the transient simulation results of liquid permeation in coal stacks showed when the liquid flowed through the channel with changed diameter from large to small ones,the transportation distance was several times longer than that through the unidiameter *** trend of liquid“relay-mode”in capillaries can be used to promote the permeation in granular materials porous media *** relevant results also provide new thoughts to develop the water-based fire extinguishing agents and then improve the firefighting efficiency of deep-seated fire in porous media stacks.

关键词： Granular materials Porous media Safety Permeation Water-based fire extinguishing agent

科教兴省、人才强省背景下河南全方位育才、引才、用才的路径与对策研究

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焦作大学学报 2024年第2期38卷 45-48,52页

作者：王慧王康李海涛焦作大学人文学院河南焦作454000 焦作大学人事处河南焦作454000

当今世界展开的全方位竞争本质上是人才的竞争,谁拥有的人才数量更多并能发挥他们的最大潜力,谁就能赢得竞争。河南未来要想在国内科技、经济、文化领域扮演更重要的角色,就必须加快推动产业结构的战略性调整,推进“四个强省”建设,而... 详细信息

当今世界展开的全方位竞争本质上是人才的竞争,谁拥有的人才数量更多并能发挥他们的最大潜力,谁就能赢得竞争。河南未来要想在国内科技、经济、文化领域扮演更重要的角色,就必须加快推动产业结构的战略性调整,推进“四个强省”建设,而这些目标的实现,离不开人才的支持和推动。梳理并分析了河南人才资源现状及其问题,提出了全方位育才、引才、用才的路径与对策,对河南未来人才队伍建设提供有益参考。

关键词：河南人才资源人才队伍建设

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基于柱形容器缠绕特性的控制稳定性分析

河北科技大学学报 2024年第1期45卷 26-34页

作者：王康路永婕郭子腾王加富张海东王君哲陈丰雨中国兵器工业集团山东北方现代化学工业有限公司山东济南250031 省部共建交通工程结构力学行为与系统安全国家重点实验室河北石家庄050043 河北科技大学机械工程学院河北石家庄050018

针对玻璃纤维缠绕机在工作中由于张力不稳定导致的线型变化,以及在高速缠绕模式下的张力调节不稳定的问题,设计了自适应模糊PID控制策略以及适用于高速缠绕工况的滑模控制策略。首先,针对缠绕工况建立缠绕动力学模型、张力控制模型;其次... 详细信息

针对玻璃纤维缠绕机在工作中由于张力不稳定导致的线型变化,以及在高速缠绕模式下的张力调节不稳定的问题,设计了自适应模糊PID控制策略以及适用于高速缠绕工况的滑模控制策略。首先,针对缠绕工况建立缠绕动力学模型、张力控制模型;其次,引入模糊PID控制策略和滑模控制策略分别对不同工况下的缠绕特性进行MATLAB-Simulink仿真,寻找最优控制策略;最后,基于被验证的最优控制策略进行实验。结果表明,在模糊PID控制的调节下,不同速度变化下的缠绕张力相对于无控制得到较好改善,提高了柱形容器在缠绕时的线性稳定性和张力稳定性。模糊PID控制对缠绕时的张力调节精度优于滑模控制,为大型管道缠绕设备提供了新的研究思路。

关键词：自动控制理论纤维缠绕 MATLAB-Simulink仿真模糊PID控制滑模控制硬件实验

A three-dimensional modeling of the morphological change in the Liaodong Bay

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Frontiers of Earth Science 2015年第3期9卷 509-520页

作者： Qiushun wang Haigui kang State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China

The morphology in the Liaodong Bay has undergone a marked change over the past decades due to the cutoff of nearby rivers. The fine sediment of the bay consists of both non-cohesive and cohesive fractions with relatively small particles over the seabed. Thus, a three- dimensional morphodynamic model accounting for non- cohesive and cohesive fractions is established to investi- gate the morphological change without sediment input from nearby rivers. A representative wave is chosen to compute the wave distribution in the Liaodong Bay and depth-dependent wave radiation stresses are employed by the hydrodynamic model. The advection-diffusion equa- tion is used to simulate the fine sediment transport under the representative wave and tidal currents. The erosion flux of non-cohesive and cohesive sediment is taken into account. The simulated results of tidal level, velocities, directions, and sediment concentrations are in agreement with the measured data. The results demonstrate that the present model, which takes the erosion flux of both non- cohesive and cohesive fractions into account, gives more reasonable values than when accounting for cohesive sediment alone. When the three-dimensional morphody- namic model is applied to predict morphological change over the course of a year, the deposition is shown to be relatively small and the range of the erosion is increased compared to previous results of sediment input from the river. It can be concluded that the erosion in the Liaodong Bay is increasing due to the cutoff of the river, and that morphological evolution must be taken into account if any type of coastal construction plans are to be carried out over the seabed.

关键词： fine sediment three-dimensional model morphological change representative wave

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陕西乡村振兴与新型城镇化协同推进研究

商洛学院学报 2024年第2期38卷 91-96页

作者：张敏王建康陕西省社会科学院陕西西安710065

协同推进乡村振兴和新型城镇化是解决城乡发展不平衡、农村发展不充分的关键举措。系统梳理了陕西省协同推进乡村振兴与新型城镇化的做法、成效,从空间协同、经济协同、要素协同和社会协同等维度,分析影响协同的突出制约因素,进而提出... 详细信息

协同推进乡村振兴和新型城镇化是解决城乡发展不平衡、农村发展不充分的关键举措。系统梳理了陕西省协同推进乡村振兴与新型城镇化的做法、成效,从空间协同、经济协同、要素协同和社会协同等维度,分析影响协同的突出制约因素,进而提出协同推进乡村振兴与新型城镇化的对策:构建新型城镇体系,推动县城建设高质量发展;培育特色优势产业,促进产业链主体留在县域;深化要素市场化配置改革,保障城乡资源自由流动;贯彻城乡共享发展理念,优化城乡公共资源配置。

关键词：乡村振兴新型城镇化城乡融合陕西

Directing group-assisted transition-metal-catalyzed vinylic C–H bond functionalization

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Science China Chemistry 2015年第8期58卷 1252-1265页

作者： kang wang Fangdong Hu Yan Zhang Jianbo wang Beijing National Laboratory of Molecular Sciences (BNLMS) Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry Peking University

Transition-metal-catalyzed C–H bond activation represents one of the most attractive research areas in organic *** contrast to the great developments made in directed C–H bond functionalization of arenes,the directing group-assisted activation of non-aromatic vinylic C–H bonds still remains *** the recent years,significant progress has been made in this fascinating field with various functionalized alkenes,heterocycles and carbocycles being *** article will focus on the recent achievements in the field of directing-group-assisted vinylic C–H bond functionalization.

关键词： transition-metal-catalysis organic synthesis C-H bond functionalization vinylic C-H bond

考虑降压节能和光伏误差三维特性的主动配电网多时间尺度优化调度

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电力建设 2024年第8期45卷 159-172页

作者：张光儒马振祺陈杰张家午王康冯天橼王成福国网甘肃省电力公司电力科学研究院兰州市730070 山东大学电气工程学院济南市250061

高比例分布式光伏的分散、随机特性加剧了配电系统潮流分布的不确定性,使得配电系统的安全经济运行面临严峻挑战。提出了考虑降压节能调节和分布式光伏预测误差三维特性的主动配电网多时间尺度优化调度方法。首先,分析负荷功率与馈线电... 详细信息

高比例分布式光伏的分散、随机特性加剧了配电系统潮流分布的不确定性,使得配电系统的安全经济运行面临严峻挑战。提出了考虑降压节能调节和分布式光伏预测误差三维特性的主动配电网多时间尺度优化调度方法。首先,分析负荷功率与馈线电压的灵敏度关系,提出了基于降压节能调节方法的综合负荷建模方法。其次,从时间-空间-功率三维角度,建立了一种分布式光伏预测误差的三维分析模型,为调度提供更精准的误差分析结果。然后,基于降压节能方法和预测误差三维分析模型,构建了可有效协调日前慢速调节资源与日内快速响应资源的主动配电网多时间尺度优化调度模型。最后,以改进IEEE 33节点系统为算例进行分析,算例分析结果表明所提误差建模方法对光伏功率有着较好的跟随效果,且基于该模型的优化调度策略能够减少误差随机性对调度决策的影响,提升配电系统运行的安全性与经济性。

关键词：主动配电网优化调度分布式光伏预测误差建模降压节能技术多时间尺度