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Design and optimization of diffraction-limited storage ring lattices based on many-objective evolutionary algorithms

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Nuclear Science and Techniques 2023年第10期34卷 20-35页

作者： He-Xing Yin Jia-Bao Guan Shun-Qiang Tian Ji-Ke Wang The Institute for Advanced Studies Wuhan UniversityWuhan 430072China Shanghai advanced Research institute Chinese Academy of SciencesShanghai 201210China

Multi-objective evolutionary algorithms(MOEAs) are typically used to optimize two or three objectives in the accelerator field and perform well. However, the performance of these algorithms may severely deteriorate when the optimization objectives for an accelerator are equal to or greater than four. Recently, many-objective evolutionary algorithms(MaOEAs)that can solve problems with four or more optimization objectives have received extensive attention. In this study, two diffraction-limited storage ring(DLSR) lattices of the Extremely Brilliant Source(ESRF-EBS) type with different energies were designed and optimized using three MaOEAs and a widely used MOEA. The initial population was found to have a significant impact on the performance of the algorithms and was carefully studied. The performances of the four algorithms were compared, and the results demonstrated that the grid-based evolutionary algorithm(GrEA) had the best performance.Ma OEAs were applied in many-objective optimization of DLSR lattices for the first time, and lattices with natural emittances of 116 and 23 pm·rad were obtained at energies of 2 and 6 GeV, respectively, both with reasonable dynamic aperture and local momentum aperture(LMA). This work provides a valuable reference for future many-objective optimization of DLSRs.

关键词： Storage ring lattices Many-objective evolutionary algorithms GrEA algorithm NSGA

Assessment of groundwater potential using multi-criteria decision analysis and geoelectrical surveying

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Geo-Spatial Information Science 2022年第4期25卷 600-618页

作者： Marzieh Shabani Zohreh Masoumi Abolfazl Rezaei Department of Earth Sciences Institute for Advanced Studies in Basic Sciences(IASBS)ZanjanIran Center for Research in Climate Change and Global Warming(CRCC) Institute for Advanced Studies in Basic Sciences(IASBS)ZanjanIran

A precise map of the dispersion of the groundwater potential across each watershed can help decision-makers to exert optimal water management in each region.In this research,the potential of groundwater resources in both the Zanjanrood Catchment and the Tarom Region,located in the northwest of Iran,has been studied.Seven effective criteria including slope,land-use,drainage density,spring density,lithology,lineament density,and rainfall are considered.Criteria were first weighted using the Analytical Hierarchical Process(AHP)method and then overlaid by the Technique for Order Preferences by Similarity to Ideal(TOPSIS)model.Finally,the spatial zoning map of groundwater potential was obtained in four categories.A sensitivity analysis was performed to determine the influence of each criterion on the obtained map.The model was verified using both the spatial distribution of the high-discharged production wells and the geophysical-based geoelectric field surveys.The results indicate that the high-discharged wells(>40 l/s)in both regions are dispersed predominantly in the very good zone and,in several cases,in the good zone.Besides,the results from the two-dimensional models of resistivity and induced polarization of geoelectrical field survey are inappropriate agreement with those from the TOPSIS method.Notably,there is no suitable potential zone of groundwater in the surrounding highlands to be used in the future for drinking purposes since the highlands water supply is a strategic supply for drinking.The strategies employed in this study,the results of GIS modeling,and the geoelectrical analysis can be considered for sustainable development of similar arid and semi-arid areas since groundwater is considered as the main supplier of water in such regions.

关键词： Spatial Information System(GIS) Remote Sensing(RS) groundwater potential TOPSIS geoelectrical field survey sustainable development

Precise electro-reduction of alkyl halides for radical defluorinative alkylation

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Science China Chemistry 2022年第4期65卷 762-770页

作者： Xingxiu Yan Shengchun Wang Zhao Liu Yujie Luo Pengjie Wang Wenyan Shi Xiaotian Qi Zhiliang Huang Aiwen Lei institute for advanced studies(IAS)and College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China

Reported here is a precise electro-reduction strategy for radical defluorinative alkylation towards the synthesis of gem-difluoroalkenes from α-trifluoromethylstyrenes. According to the redox-potential difference of the radical precursors, direct or indirect electrolysis is respectively adopted to realize the precise reduction. An easy-to-handle, catalyst-and metal-free condition is developed for the reduction of alkyl radical precursors that are generally easier to be reduced than α-trifluoromethylstyrenes,while a novel electro-Ni-catalytic system is established for the electro-reduction of alkyl bromides or chlorides towards the electrochemical synthesis of gem-difluoroalkenes. The merit of this protocol is exhibited by its mild conditions, wide substrate scope, and scalable preparation. Mechanistic studies and DFT calculations proved that the coordination of α-trifluoromethylstyrenes to Ni-catalyst prevents the direct reduction of the alkene and, in turn, promotes the activation of alkyl bromide through halogen atom transfer mechanism.

关键词： electro-reductive cross-coupling gem-difluoroalkenes radical defluorinative alkylation electro/nickel catalysis C-C bonds formation

Diversity-Oriented Synthesis of Flavones and Isoflavones via Palladium/Norbornene Cooperative Catalysis

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Chinese Journal of Chemistry 2022年第6期40卷 675-680页

作者： Yuanyuan Ma Qianwen Gao Lan Zhou Shanshan Liu Hong-Gang Cheng Qianghui Zhou institute for advanced studies Wuhan UniversityWuhanHubei 430072ChinaSauvage Center for Molecular SciencesCollege of Chemistry and Molecular Sciences at Wuhan UniversityWuhanHubei 430072China institute for advanced studies Wuhan UniversityWuhanHubei 430072China

Flavones and isoflavones are recognized as privileged heterocyclic scaffolds for the preparation of bioactive compounds.Efficient methods to access these heterocycles are in urgent need.Herein,we report diversity-oriented synthesis of flavones and isoflavones from 3-iodochromones via palladium/norbornene cooperative catalysis.The success of this research relies on the use of a unique bridge-head ester modified norbornene derivative as the mediator.Salient features of this include readily available starting materi-als regarding 3-iodochromones,ortho-C-H arylating and alkylating reagents and ipso-terminating reagents,broad substrate scope,good chemoselectivity,good step-economy and scalability.A large number of structurally diversified flavones,isoflavones and 2,3-diarylated chromones can be quickly prepared in a predictable manner.As showcased by the efficient formal synthesis of um-bralisib,this chemistry can be treated as another valuable addition to the toolbox of medicinal chemists.

关键词： Diversity-oriented synthesis Oxygen heterocycle Palladium Norbornene C-H activation

Visible-light-activated aziridination reaction enables simultaneous resolving of C=C bond location and the sn-position isomers in lipids

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Chinese Chemical Letters 2024年第4期35卷 481-485页

作者： Qiongqiong Wan Yanan Xiao Guifang Feng Xin Dong Wenjing Nie Ming Gao Qingtao Meng Suming Chen The Institute for Advanced Studies Renmin Hospital of Wuhan UniversityWuhan UniversityWuhan 430072China

There is a close relationship between the biological functions of lipids and their structures, and various isomers greatly increases the complexity of lipid structures. The C=C bond location and sn-position are two of the essential attributes that determine the structures of unsaturated lipids. However, simultaneous identification of both attributes remains challenging. Here, we develop a visible-light-activated aziridination reaction system, which enables the dual-resolving of the C=C bond location and sn-position isomerism of in lipids when combines with liquid chromatography-mass spectrometry(LC-MS). Based on the derivatization of C=C bonds with Ph I=NTs, their location in lipids could be easily identified by tandem MS. Especially, the sn-position isomers of unsaturated phosphatidylcholine(PC) can be separated and quantified by LC-MS after the derivatization. By using the proposed method, the significant changes of the sn-position isomers ratios of PC in mouse brain ischemia were revealed. This study offers a powerful tool for deep lipid structural biology.

关键词： Aziridination Lipid isomers C=C bond location sn-Position Mass spectrometry

Electrooxidation-Induced C(sp^(3))-H/C(sp^(2))-H Radical-Radical Cross-Coupling between Xanthanes and Electron-Rich Arenes

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Chinese Journal of Chemistry 2022年第12期40卷 1422-1428页

作者： Yuwei Liang Linbin Niu Xing-An Liang Shengchun Wang Pengjie Wang Aiwen Lei College of Chemistry and Molecular Sciences Institute for Advanced Studies(IAS)Wuhan UniversityWuhanHubei 430072China

The arylation of C(sp^(3))-H bonds has been a priority research topic in organic synthesis.Minsici reactions have been the powerful methods for C(sp^(3))-C(sp^(2))bonds formation.Despite its mature development,the scopes of arenes are usually suitable for elec-tron-deficient heterocyclic compounds,rather than electron-rich arenes.Herein,we report an electrooxidation-induced alkylation of electron-rich arenes with H_(2) evolution under exogenous oxidant-free conditions,avoiding the utilization of metal catalysts.This pro-tocol is well performed with various electron-rich aniline derivatives and nitrogen-containing heterocyclic compounds.We anticipate that this electro-oxidative C(sp^(3))-H arylation represents an important expansion for the classic arenes alkylation,thereby proving an attractive strategy for the developments of radical cross-coupling chemistry.

关键词： Electrochemistry C-H activation C-C coupling C(sp^(2))-H alkylation Electron-rich arenes

Taking Time, Sharing Spaces: Adaptive Risk Governance Processes in Rural Japan

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International Journal of Disaster Risk Science 2018年第4期9卷 464-471页

作者： Ilan Chabay institute for advanced Sustainability studies (IASS) 14467 PotsdamGermany

Rural and peri-urban communities in Japan, as well as in many other regions of the world, face risks of discrete event natural phenomena, including earthquakes,floods, and landslides. They also face persistent disruptive stress due to risks that remain active over long durations,such as the loss of community capacities due to an aging population. This article describes my observations of and subsequent reflections on adaptive risk governance and community resilience building processes in two areas of western and southern Japan—Chizu in Tottori Prefecture and towns near Kumamoto City in Kumamoto Prefecture.Four aspects of adaptive risk governance from this limited set of observations stood out:(1) the importance of establishing a durable, patient process,(2) initiated and facilitated by a trusted figure, in(3) a space or venue accessible and open to the community, and(4) augmented by boundary objects that facilitate role playing, iteration,and ownership by the community of solutions generated in these dialogues.

关键词： Boundary objects Case Station-Field Campuses(CASiFiCA) Community resilience Knowledge Learning and Societal Change Alliance(KLASICA) Japan Risk governance Yonmenkaigi System Method(YSM)

Multi objective prediction and optimization of control parameters in the milling of aluminium hybrid metal matrix composites using ANN and Taguchi-grey relational analysis

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Defence Technology（防务技术） 2019年第4期15卷 545-556页

作者： S.Ajith Arul Daniel R.Pugazhenthi R.Kumar S.Vijayananth Department of Mechanical Engineering Vels Institute of ScienceTechnology and Advanced Studies

This study aims to optimize the input parameters such as mass fraction and particle size of SiC along with depth of cut,feed and cutting speed in the milling of Al5059/SiC/MoS2.The hybrid metal matrix composites are generally fabricated by reinforcing of different sizes(10,20,40 μm)of SiC with aluminium at a different levels(5%,10%& 15%)whereas the MoS2 addition is fixed as 2%.The effect of each control factor on response variables are analyzed through Taguchi S/N ratio method.Also,the most significant method for prediction of response parameters is satisfied by ANN model than the regression model.Analysis of variance(ANOVA)results envisage that mass fraction of SiC,feed rate is the most domineering factor on response variable.

关键词： Silicon carbide Temperature Surface roughness Cutting forces Artificial neural network Grey relational analysis

Tuning radical reactivity for selective radical/radical cross-coupling

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Science Bulletin 2018年第15期63卷 1006-1009页

作者： Shengchun Wang Shan Tang Aiwen Lei institute for advanced studies (IAS) College of Chemistry and Molecular Sciences Wuhan University

Radical/radical cross-coupling represents a straightforward way for the construction of new chemical bonds in theory and has received more and more attention over the past several years. Until now, it is challenging to achieve the selective bond formation between two transient radicals since selective radical cross-coupling usually happens between persistent radical and transient radical. However, the number of persistent radicals is much less than that of transient radicals. These issues limit the application of radical/radical cross-coupling in the construction of new chemical bonds. To solve this, we proposed a novel strategy ‘‘tuning radical reactivity" that could tune transient radical into persistent radical. This paper will introduce the concept and recent developments of ‘‘tuning radical reactivity".

关键词：反应直接方法分子构造化学