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Synthesis of Organofluorine Compounds with Acylsilanes

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Chinese Journal of Chemistry 2024年第8期42卷 887-902页

作者： Youyuan guo gang Zhou Xiao Shen The Institute for Advanced Studies Engineering Research Center of Organosilicon Compounds&MaterialsMinistry of EducationWuhan University299 Bayi RoadWuhanHubei430072 China

Comprehensive Summary,Organofluorine compounds are central in synthetic chemistry,medicinal chemistry and material *** this review,we summarize the investigations on the synthesis of organofluorine compounds with *** the non-fluorinated acylsilanes,the in situ generation of difluoroenoxysilanes from the reactions of the acylsilanes with trifluoromethylation reagents is the major pathway,leading to the facile preparation of variousα,α-*** the fluoroalkylacylsilanes,apart from the in situ generation of difluoroenoxysilanes through anion Brook rearrangement,radical Brook rearrangement of the photoexcited acylsilanes and the selective control of reactivities of the biradicals pave the way for the synthesis of a variety of organofluorine *** general,most of these reactions gave racemic products,and the asymmetric synthesis of organofluorine compounds with acylsilanes is still rare,which would be a future.

关键词： Acylsilanes Organofluorine compounds Brook rearrangement Radical rearrangement β-Fluoride elimination Asymmetric catalysis Photocatalysis Defluoroalkylation

Fluid-structure interaction simulation for multi-body flexible morphing structures

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Chinese Journal of Aeronautics 2024年第2期37卷 137-147页

作者： Wenzhi guo Yongtao SHUI Lu NIE gang CHEN State Key Laboratory of Strength and Vibration for Mechanic Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China China Academy of Launch Vehicle Technology Beijing 100076China China Academy of Aerospace Science and Innovation Beijing 100086China Shannxi Key Laboratory of Service Environment and Control for Flight Vehicles Xi’an Jiaotong UniversityXi’an 710049China

The multi-body flexible morphing airfoil can improve the aerodynamic characteristics based on different flight missions *** researches have focused on the unsteady aerodynamic characteristics of flexible wings under passive ***,the unsteady aerodynamic characteristics with the fluid-structure interaction effects in the multi-body active actuation process of morphing airfoil deserve further *** this paper,a fluid-structure coupled simulation method for multi-body flexible morphing airfoil with active actuation subsystem was investigated,and the aerodynamic characteristics during deformation were compared with different skin flexibility,flow field environment,actuation mode and actuation *** numerical results show that for the steady aerodynamic,the skin flexibility can improve the stability *** the unsteady process,the change trend of the transient lift coefficient and pitching moment are consistent with those of the active drive characteristics,while the instantaneous lift-drag ratio coefficient is greatly affected by the driving mode and can be improved by increasing the driving duration.

关键词： Fluid-structure interaction Multi-body dynamics modeling Flexible structures Aerodynamics Morphing wings

Plant phenolics mediated bottom-up effects of elevated CO2 on Acyrthosiphon pisum and its parasitoid Aphidius avenae

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Insect Science 2020年第1期27卷 170-184页

作者： hong-Yu Yan hong-gang guo Yu-Cheng Sun Feng Ge State Key Laboratory of Integrated Management of Pest and Rodents Institute of ZoologyChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina

Elevated concentrations of atmospheric CO2 can alter plant secondary metabolites,which play important roles in the interactions among plants,herbivorous insects and natural ***,few studies have examined the cascading effects of host plant secondary metabolites on tri-trophic interactions under elevated CO2(eCO2).In this study,we determined the effects of eCO2 on the growth and foliar phenolics of Medicago truncatula and the cascading effects on two color genotypes oiAcyrthosiphon pisum(pink ***)and their parasitoid Aphidius avenae in the field open-top *** results showed that eCO2 increased photosynthetic rate,nodule number,yield and the total phenolic content of ***2 had contrasting effects on two genotypes of ***;the green genotype demonstrated increased population abundance,fecundity,growth and feeding efficiency,while the pink genotype showed decreased fitness and these were closely associated with the foliar genstein ***,eCO2 decreased the parasitic rate of *** independent of aphid ***2 prolonged the emergence time and reduced the emergence rate and percentage of females when associated with the green genotype,but little difference,except for increased percentage of females,was observed in *** under eCO2 when associated with the pink genotype,indicating that parasitoids can perceive and discriminate the qualities of aphid *** concluded that eCO2 altered plant phenolics and thus the performance of aphids and *** results indicate that plant phenolics vary by different abiotic and biotic stimuli and could potentially deliver the cascading effects of eCO2 to the higher trophic *** results also suggest that the green genotype is expected to perform better in future eCO2 because of decreased plant resistance after its infestation and decreased parasitic rate.

关键词： Acyrthosiphon pisum:Aphidius avenae elevated CO2 Medicago truncatula' phenolics tri-trophic level

New Cutting Force Modeling Approach for Flat End Mill

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Chinese Journal of Aeronautics 2007年第3期20卷 282-288页

作者： WAN Min ZHANG Wei-hong TAN gang QIN guo-hua Sino-French Laboratory of Concurrent Engineering The Key Laboratory of Contemporary Design ＆ Integrated Manufacturing Technology Northwestern Polytechnical University Xi＇an 710072 China

A new mechanistic cutting force model for flat end milling using the instantaneous cutting force coefficients is proposed. An in-depth analysis shows that the total cutting forces can be separated into two terms: a nominal component independent of the runout and a perturbation component induced by the runout. The instantaneous value of the nominal component is used to calibrate the cutting force coefficients. With the help of the perturbation component and the cutting force coefficients obtained above, the cutter runout is identified. Based on simulation and experimental results, the validity of the identification approach is demonstrated. The advantage of the proposed method lies in that the calibration performed with data of one cutting test under a specific regime can be applied for a great range of cutting conditions.

关键词：建立模型飞机制造轧模机切割力

Mixed H_(∞)/Passive Exponential Synchronization for Delayed Memristive Neural Networks with Switching Event-Triggered Control

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Journal of Systems Science & Complexity 2024年第1期37卷 294-317页

作者： WU Wenhuang guo Lulu CHEN hong Shanghai Research Institute for Intelligent Autonomous Systems Tongji UniversityShanghai 200092China Department of Control Science and Engineering Tongji UniversityShanghai 201804China

This paper is devoted to event-triggered synchronization of delayed memristive neural networks with H∞and passivity *** aim is to guarantee the exponential synchronization and mixed H∞and passivity control for memristive neural networks by using event-triggered ***,a switching system is constructed under the event-triggered control ***,by adopting a piece-wise Lyapunov functional,a sufficient condition is established for the exponential synchronization and mixed H_(∞)and passivity ***,an event-triggered controller design scheme is proposed using matrix decoupling ***,the effectiveness of the designed controller is exemplified by a numerical example.

关键词： Event-triggered control exponential synchronization memristive neural networks time delays.

Effect of cerium on microstructure,texture and properties of ultrahigh-purity copper

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Journal of Rare Earths 2024年第1期42卷 220-227,I0008页

作者： Yunxiao Hua Haitao Liu Kexing Song Jiangwei Wang Yin'gang guo Jing Tian Huiwen guo Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal New Materials and Advanced Processing Technology School of Materials Science and EngineeringHenan University of Science and TechnologyLuoyang471023China Henan Academy of Sciences Zhengzhou450000China Center of Electron Microscopy and State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou310027China Henan Zhongyuan Gold Smelter Co. Ltd.Sanmenxia472100China Chinalco Luoyang Copper Processing Co. Ltd.Luoyang471039China

The effects of Ce addition(310 ppm and 1500 ppm)on the microstructure,texture and properties of ultrahigh-purity copper(99.99999%)were systematically studied using scanning electron microscopy(SEM),transmission electron microscopy(TEM)and electron backscattered diffraction(EBSD)analyses,combined with the microhardness and conductivity *** the microstructure of the as-cast and as-extruded samples,the addition of Ce refines the grain size of the ultrahigh-purity copper and the refinement effect of 310Ce alloy is greater than that of 1500Ce *** is due to the stronger compone nt supercooling and the accele rated recrystallization caused by lower Ce co *** addition,Ce can react with Cu to form the Cu-Ce eutectic phases,which are deformable during the hot ***,the added Ce can weaken the texture,showing a variation of brass recrystallization(BR),rotated cube,copper and S texture components,which depends on the recrystallization,the particle stimulated nucleation(PSN)as well as the stacking fault energy(SFE).Most remarkably,the introduction of Ce enhances the hardness of the ultrahigh-purity copper without obviously reducing its *** major{111}orientations and the stress distributions are responsible for such a superior conductivity of the Ce-containing alloys.

关键词： Ce addition Grain refinement Texture Conductivity Ultrahigh-purity copper Rare earths

Nutrition impacts of non-solid cooking fuel adoption on under-five children in developing countries

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Journal of Integrative Agriculture 2024年第2期23卷 397-413页

作者： Yalin Tang Yuhe guo gang Xie Chengfang Liu China Center for Agricultural Policy School of Advanced Agricultural SciencesPeking UniversityBeijing 100871China Agricultural Information Institute Chinese Academy of Agricultural SciencesBeijing 100081China

This paper examines the nutrition impacts of using non-solid cooking fuel on under-five children in developing *** draw on data from more than 1.12 million children in 62 developing countries from the Demographic and Health Surveys(DHS).Results from both fixed effects(FE)and instrumental variable(IV)estimates show that using non-solid cooking fuel significantly improves the nutrition outcomes of under-five *** with their peers from households mainly using solid fuel,children from households mainly using non-solid fuel exhibit a lower probability of experiencing stunting(by 5.9 percentage points)and being underweight(by 1.2 percentage points).Our further investigation provides evidence for several underlying mechanisms,such as improved indoor air quality,induced reduction in children’s respiratory symptoms,benefits on maternal health,and reduction in maternal time spent on fuel collection or *** analyses suggest that the nutrition benefits of using non-solid cooking fuel are more prominent among boys,children above three years old,and those from households of lower socioeconomic status,rural areas,and Southeast Asia.

关键词： non-solid cooking fuel nutrition benefits under-five children developing countries

Coupling N-doping and confined Co3O4 on carbon nanotubes by polydopamine coating strategy for pleiotropic water purification

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Rare Metals 2024年第7期43卷 3146-3160页

作者： Wen-Long Tu gang Wang Yue Zhang hong-Yang Zhu Rong-Rong Du hong-Yao Zhao Sheng Tang Zeng-Jing guo Jun Yang Fu Yang Cheng-Zhang Zhu School of Environmental and Chemical Engineering Jiangsu University of Science and Technology School of Chemistry and Chemical Engineering Liaocheng University School of Material Science and Engineering Jiangsu University of Science and Technology School of Environmental Science and Engineering Nanjing Tech University

The development of effective and sustainable solutions for pleiotropic water purification becomes urgent and *** Fenton-like catalysts for activation of peroxymonosulfate（PMS） to purify organic wastewater show great *** this work,by tuning metal loading with an in-situ polydopamine coating strategy,oxygen vacancy-enriched Co3O4loading on N-doped carbon nanotubes（CNTs） were constructed to enhance PMS activation efficiency for pollutants ***,the obtained modified CNTs afford a well-developed N-containing network structure,which is further endowed with abundant Co（Ⅱ）/Co（Ⅲ） redox cycles and significant metal-carbon *** particular,the surface N doping in CNTs might induce the oriented enrichment of pollutants around the catalyst,which reduces the migration distance and correspondingly improves the utilization of reactive oxidative *** electron transfer efficiency of the catalyst can be further improved by incorporating oxygen vacancy-enriched *** performance results show that the optimal NC/Co-1 could mineralize 20 × 10-6of bisphenol A（BPA） by almost 98% in 8 min.A low reaction activation energy(26.05 kJ·mol-1) in BPA degradation was demonstrated by the NC/*** importantly,NC/Co-1 can inherit excellent degradation performance towards oxytetracycline,2,4-dichlorophenol,and tetracycline,showing wide practical *** addition,by virtue of the photothermal conversion property,NC/Co-1 achieves an additive function for interfacial solar water evaporation(1.84 kg·m-2·h-1,112.51%),showing impressive potential for clean water recovery under complicated environmental pollution conditions.

关键词： Carbon nanotube Advanced oxidation process Co 3 O 4 Photothermal conversion Solar water evaporation

Constructing core@shell structured photothermal nanosphere with thin carbon layer confined Co-Mn bimetals for pollutant degradation and solar interfacial water evaporation

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Rare Metals 2024年第4期43卷 1686-1701页

作者： hong-Yang Zhu Meng-Ting Liu gang Wang Rong-Rong Du hong-Yao Zhao Hao Lu Shi-Qi Yang Sheng Tang Zeng-Jing guo Jun Yang Cheng-Zhang Zhu Fu Yang School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang212003China School of Chemistry and Chemical Engineering Liaocheng UniversityLiaocheng252000China School of Material Science and Engineering Jiangsu University of Science and TechnologyZhenjiang212003China School of Environmental Science and Engineering Nanjing Tech UniversityNanjing210009China

Photothermal material applied in environmental governance has attracted growing *** combining the Stober method and dopamine-triggered coating strategy,Co-Mn precursor was in situ incorporated into the poly dopamine(PDA)layer over the surface of silica ***,a unique photothermal nanosphere with SiO_(2)core and thin carbon layer and dual Co-Mn oxides shell was allowed to form by sequential heat treatment in the inert atmosphere(SiO_(2)@CoMn/C).The bimetallic fraction of Co/Mn in the carbon layer and post-treatment calcination temperature was comprehensively tuned to optimize the peroxymonosulfate(PMS)activation performance of the *** state of bimetallic species was studied including their physical distribution,chemical valence,and interplay by various ***,Co oxides appear as dominant monodispersed nanoparticles(~10 nm),while Mn with cluster-like morphology is observed to uniformly distribute over thin-layer carbon and adhered to the surface of SiO_(2)nanospheres(~250 nm).The calcined temperature could tune the oxidized state of Co species,leading to the optimization of the catalytic performance of introduced dual metal *** a result,this obtained optimal catalyst integrated the advantages of exposed bimetallic CoMn species and N-doped thin carbon to deliver excellent catalytic PMS activation performance and photothermal synergetic catalytic mineralization ability for diversiform *** reactions condition controls and anion interference studies were conducted to identify the adaptability of the optimal ***,the application of solar-driven interfacial water evaporation using optimal SiO_(2)@Co_3Mn_1/C-600 catalyst was explored,showing a high water evaporation rate of 1.48 kg·m^(-2)·h^(-1)and an efficiency of 95.2%,further revealing a comprehensive governance functionality of obtained material in the complex pollution condition.

关键词： Photothermal Peroxymonosulfate(PMS)activation Bimetallic synergy Water evaporation Advanced oxidation process