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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

FPD Net:Feature Pyramid DehazeNet

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Computer Systems Science & Engineering 2022年第3期40卷 1167-1181页

作者： Shengchun Wang Peiqi Chen Jingui Huang Tsz Ho Wong College of Information Science and Engineering Hunan Normal UniversityChangsha410081China Blackmagic Design RowvilleVIC3178Australia

We propose an end-to-end dehazing model based on deep learning(CNN network)and uses the dehazing model re-proposed by AOD-Net based on the atmospheric scattering model for dehazing.Compare to the previously proposed dehazing network,the dehazing model proposed in this paper make use of the FPN network structure in the field of target detection,and uses five feature maps of different sizes to better obtain features of different proportions and different sub-regions.A large amount of experimental data proves that the dehazing model proposed in this paper is superior to previous dehazing technologies in terms of PSNR,SSIM,and subjective visual quality.In addition,it achieved a good performance in speed by using EfficientNet B0 as a feature extractor.We find that only using high-level semantic features can not effectively obtain all the information in the image.The FPN structure used in this paper can effectively integrate the high-level semantics and the low-level semantics,and can better take into account the global and local features.The five feature maps with different sizes are not simply weighted and fused.In order to keep all their information,we put them all together and get the final features through decode layers.At the same time,we have done a comparative experiment between ResNet with FPN and EfficientNet with BiFPN.It is proved that EfficientNet with BiFPN can obtain image features more efficiently.Therefore,EfficientNet with BiFPN is chosen as our network feature extraction.

关键词： Deep learning dehazing image restoration

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

Stress and Strain in Perovskite/Silicon Tandem Solar Cells

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Nano-Micro Letters 2023年第4期15卷 272-276页

作者： Kong Liu Zhijie wang shengchun Qu Liming Ding Key Laboratory of Semiconductor Materials Science(CAS) Beijing Key Laboratory of Low Dimensional Semiconductor Materials and DevicesInstitute of SemiconductorsChinese Academy of SciencesBeijing 100083People’s Republic of China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049People’s Republic of China Center for Excellence in Nanoscience(CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190People’s Republic of China

Tandem solar cells based on metal halide perovskites are advancing rapidly during last few years[1–17].The certified power conversion efficiency(PCE)for monolithic perovskite/silicon tandem solar cell reaches 32.5%[18].Since tandem solar cells contain more layers than single-junction solar cells,stress/strain control is an issue during fabrication and further practical operation.The stress can not only affect the stability of the perovskite layer but also change the optoelectronic properties of the films[19–23].

关键词： perovskite halide stability

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

Electrochemical Oxidative [4+2] Annulation of Different Styrenes toward the Synthesis of 1,2-Dihydronaphthalenes

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CCS Chemistry 2022年第5期4卷 1557-1564页

作者： Kailun Liang Shengchun Wang Hengjiang Cong Lijun Lu Aiwen Lei College of Chemistry and Molecular Sciences Institute for Advanced Studies(IAS)Wuhan UniversityWuhanHubei 430072 National Research Center for Carbohydrate Synthesis Jiangxi Normal UniversityNanchangJiangxi 330022

A[4+2]annulation of two different styrenes to construct polysubstituted 1,2-dihydronaphthalenes was achieved.This transformation proceeded smoothly under electrochemical oxidative conditions without metal catalysts and external oxidants.A series of polysubstituted 1,2-dihydronaphthalenes were obtained with high regioselectivity and diastereoselectivity.Moreover,polysubstituted 1,2-dihydronaphthalenes were further transformed to polysubstituted 1,2,3,4-tetrahydronaphthalenes and polysubstituted naphthalenes,which show great potential in synthetic applications.

关键词： electrochemical synthesis styrenes [4+2]annulation 1,2-dihydronaphthalenes regioselectivity and diastereoselectivity

Efficacy of needling acupoints of Guanyuan(CV4), Sanyinjiao(SP6), Zusanli(ST36), Pishu(BL20), Shenshu(BL23), Zigong(EX-CA1) on expression of p38 mitogen-activated protein kinase in ovarian tissue in rats with premature ovarian failure induced by cyclophosp

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Journal of Traditional Chinese Medicine 2021年第6期41卷 953-958页

作者： wang shengchun JIANG Yiming QIU Lirong SU Meng Department of Acupuncture Physiotherapy Rehabilitation Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250021China Specialty of acupuncture and massage Traditional Chinese Medicine of Shandong UniversityJinan 250014China

OBJECTIVE:To investigate the efficacy of needling acupoins of Guanyuan(CV4),Sanyinjiao(SP6),Zusanli(ST36),Pishu(BL20),Shenshu(BL23),Zigong(EX-CA1)on the expression of p38 mitogen-activated protein kinase(p38MAPK)in ovarian tissue in rats with premature ovarian failure induced by cyclophosphamide,and to study the underlying mechanism.METHODS:Forty specific pathogen free female Sprague-Dawley rats were randomly divided into the blank group,the model group,the acupuncture group,the Western Medicine group and the Western Medicine combined with acupuncture group.Except the blank group,the rest of the rats were given with cyclophosphamide for 14 d to establish premature ovarian failure model.No intervention was conducted in the blank group and model group;the acupuncture group was given with acupuncture daily;the Western Medicine group was given with estradiol valerate(0.09 mg/kg)by intragastrical gavage daily;the combination group was given with acupuncture combined with estradiol valerate(0.09 mg/kg)daily.Each group was intervened in continuously for 14 d.After the last treatment,the levels of estradiol(E2),follicle stimulating hormone(FSH)and luteinizing hormone(LH)were detected by enzyme-linked immunosorbent assay,then the ovarian tissue was dissected.Western blot was used to detect the expression of p38 MAPK protein.RESULTS:Compared with the blank group,E2 in the serum of rats in the model group was significantly decreased(P<0.05),FSH and LH were significantly increased(P<0.05),and the expression of p38 MAPK protein in the ovarian tissue of the rats was significantly increased(P<0.05).Compared with the model group,E2 in the serum of the acupuncture group,Western Medicine group and the combination group were significantly increased(P<0.05),FSH and LH levels were significantly decreased(P<0.05),and the expression of p38MAPK protein in the ovarian tissue of the rats was significantly decreased(P<0.05).However,there was no statistically significant difference between the Western Medicine group and the acupuncture grou

关键词： acupuncture premature ovarian insufficiency p38 mitogen-activated protein kinases signal transduction

Graph representation learning-based residential electricity behavior identification and energy management

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Protection and Control of Modern Power Systems 2023年第2期8卷 218-230页

作者： Xinpei Chen Tao Yu Zhenning Pan Zihao wang shengchun Yang School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China China Electric Power Research Institute Nanjing 210003China

It is important to achieve an efficient home energy management system(HEMS)because of its role in promoting energy saving and emission reduction for end-users.Two critical issues in an efficient HEMS are identification of user behavior and energy management strategy.However,current HEMS methods usually assume perfect knowledge of user behavior or ignore the strong correlations of usage habits with different applications.This can lead to an insuffi-cient description of behavior and suboptimal management strategy.To address these gaps,this paper proposes non-intrusive load monitoring(NILM)assisted graph reinforcement learning(GRL)for intelligent HEMS decision making.First,a behavior correlation graph incorporating NILM is introduced to represent the energy consumption behavior of users and a multi-label classification model is used to monitor the loads.Thus,efficient identification of user behavior and description of state transition can be achieved.Second,based on the online updating of the behavior correlation graph,a GRL model is proposed to extract information contained in the graph.Thus,reliable strategy under uncer-tainty of environment and behavior is available.Finally,the experimental results on several datasets verify the effec-tiveness of the proposed model.

关键词： Behavior correlation graph Graph reinforcement learning Home energy management system Multi-label classification Non-intrusive load monitoring

Numerical simulation on flow of ice slurry in horizontal straight tube

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Frontiers in Energy 2021年第1期15卷 201-207页

作者： shengchun LIU Ming SONG Ling HAO Pengxiao wang Tianjin Key Laboratory of Refrigeration Technology Tianjin University of CommerceTianjin 300134China

Numerical simulation on flow of ice slurry in horizontal straight tubes was conducted in this paper to improve its transportation characteristics and application.This paper determined the influence of the diameter and length of tubes,the ice packing factors(IPF)and the flow velocity of ice slurry on pressure loss by using numerical simulation,based on two-phase flow and the granular dynamic theory.Furthermore,it was found that the deviation between the simulation results and experimental data could be reduced from 20%to 5%by adjusting the viscosity which was reflected by velocity.This confirmed the reliability of the simulation model.Thus,two mathematical correlations between viscosity and flow velocity were developed eventually.It could also be concluded that future rheological model of ice slurry should be considered in three sections clarified by the flow velocity,which determined the fundamental difference from single-phase fluid.

关键词： ice slurry horizontal tubes numerical simulation pressure drop viscosity model

The Real Structure of Pd(OAc)_(2)in Various Solvents

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Chinese Journal of Chemistry 2021年第2期39卷 307-311页

作者： Dongchao Zhang Dali Yang Shengchun Wang Li Zeng Jie Xin Heng Zhang Aiwen Lei The Institute for Advanced Studies(IAS) College of Chemistry and Molecular SciencesWuhan UniversityWuhanHubei430072 China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling LuShanghai200032 China

Pd(OAc)_(2) is an extensively utilized palladium source in the palladium initiated transformations either directly or as a catalyst precursor. However, the comprehension of the real structure of Pd(OAc)_(2) in solution is still vague. In this work, the structure of palladium acetate in solution was studied in detail by using X-ray absorption fine structure (XAFS) spectroscopy. The results demonstrate that monomer is the main form for Pd(OAc)_(2) in the solution of 1,4-dioxane, N,N-dimethylacetamide (DMA), N,N-dimethylformamide (DMF), 1,2-dimethoxyethane (DME), MeCN and dimethyl sulfoxide (DMSO). In addition, Pd(II) could be reduced to Pd(0) in ethanol solution. The structural information in this research will benefit the understanding of the mechanism of Pd(OAc)_(2) involved organic reactions.

关键词： Palladium X-ray absorption spectroscopy Structure elucidation Solvent effects EXAFS spectroscopy