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Recent advances in visible light-mediated chemical transformations of enaminones

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Chinese Chemical Letters 2024年第2期35卷 4-15页

作者： Yu Han Liyun Zhou Chengyu wang Shangti Feng Rong Ma Jie-Ping wan College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China School of Chemistry and Chemical Engineering Linyi UniversityLinyi 276000China Linyi Sanfeng Chemical Co. Ltd.Linyi 276000China

Enaminones,which possesses both the nucleophilic enamine as well as electrophilic enone structures,are well known versatile building blocks in organic ***,visible light-mediated reactions have emerged as useful synthetic strategy with enhanced *** the last decade,various photochemical transformations of enaminones have been developed to construct cyclic or acyclic *** this review,we describe the recent advances in visible light-mediated chemical transformations of *** discussion on the reaction mechanism of the related reactions is given to provide guide to the ***,a summary on the existing challenges and the future outlook towards the development of practical photocatalytic reactions of enaminones is also presented.

关键词： Enaminone Visible light C-H functionalization C=C bond cleavage Cyclization Multicomponent reactions

Surface engineering of carbon dots for highly sensitive α-glucosidase assay and inhibition evaluation

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Chinese Chemical Letters 2024年第3期35卷 193-197页

作者： Meijuan Liang Gege Song Yeqing wan Yingying Chen Fuan wang Xiaoqing Liu College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China Oil Crops Research Institute Chinese Academy of Agricultural SciencesWuhan 430062China

Monitoringα-glucosidase(α-Glu)activity is of great significance for the early diagnosis of typeⅡ*** the blue fluorescent carbon dots(CDs)were integrated with two different recognizing molecules,β-cyclodextrin and phenylboronic acid,for assembling a multifunctional CDs(mCDs)nanoplatform for sensitively analyzingα-Glu and its *** hydrolyzed product of 4-nitrophenyl-α-D-glucopyranoside(α-Glu substrate),p-nitrophenol,could efficiently quench the fluorescence of mCDs due to its cooperative molecular recognition withβ-cyclodextrin and phenylboronic *** mCDs could be utilized for the detection ofα-Glu activity with the limit of detection of 0.030 U/***,the presentα-Glu detection platform revealed a high selectivity,and other natural enzymes showed scarcely any effect on the present mCDs *** proposed method could be facilely used to screenα-Glu inhibitors with satisfying *** rational mCDs is expected to supplement more comprehensive biosensing platforms for highly sensitive and specific recognition of disease-relevant biomarkers with clinical importance.

关键词： α-Glucosidase Carbon dots Fluorescent sensor Inhibitor β-Cyclodextrin

Gravity Wave Activity and Stratosphere-Troposphere Exchange During Typhoon Molave(2020)

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Journal of Tropical Meteorology 2024年第3期30卷 306-326页

作者： HUANG Dong wan Ling-feng wan Yi-shun CHANG Shu-jie MA Xin ZHAO Kai-jing College of Ocean and Meteorology/South China Sea Institute of Marine Meteorology/Laboratory for Coastal Ocean Variation and Disaster Prediction/Key Laboratory of Climate Resources and Environment in Continental Shelf Sea and Deep Sea(LCRE)/Key Laboratory of Space Ocean Remote Sensing and ApplicationMinistry of Natural ResourcesGuangdong Ocean UniversityZhanjiangGuangdong 524088 China Frontier Science Center for Deep Ocean Multispheres and Earth System(DOMES) Institute for Advanced Ocean Study(IAOS)Ocean University of ChinaQingdaoShandong 266100 China School of Earth and Environment University of LeedsLeeds LS29JT UK Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030 China

To investigate the stratosphere-troposphere exchange(STE)process induced by the gravity waves(GWs)caused by Typhoon Molave(2020)in the upper troposphere and lower stratosphere,we analyzed the ERA5 reanalysis data provided by the European Centre for Medium-Range Weather Forecasts and the CMA Tropical Cyclone Best Track *** also adopted the mesoscale forecast model Weather Research and Forecasting model V4.3 for numerical *** of the previous studies were about typhoon-induced STE and typhoon-induced GWs,while our research focused on the STE caused by typhoon-induced gravity *** analysis shows that most of the time,the gravity wave signal of Typhoon Molave appeared below the *** was stronger on the east side of the typhoon center(10°-20°N,110°-120°E)than on the west side,suggesting an eastward tilted structure with height *** the GWs in the upper troposphere and lower stratosphere region on the west side of the typhoon center broke up,it produced strong turbulence,resulting in stratosphere-troposphere *** this time,the average potential vorticity vertical flux increased with the average ozone mass mixing *** gravity wave events and STE process simulated by the WRF model were basically consistent with the results of ERA5 reanalysis data,but the time of gravity wave breaking was *** study indicates that after the breaking of the GWs induced by typhoons,turbulent mixing will also be generated,and thus the STE.

关键词： gravity wave typhoon stratosphere-troposphere exchange STE upper troposphere and lower stratosphere UTLS

Frequency and associated factors of accommodation and non-strabismic binocular vision dysfunction among medical university students

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 374-379页

作者： Jie Cai Wen-Wen Fan Yun-Hui Zhong Cai-Lan Wen Xiao-Dan Wei wan-Chen Wei wan-Yan Xiang Jin-Mao Chen Department of Ophthalmology First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina Digital and Intelligent Technology Transformation and Application Research Institute of Visual Function Tianjin 300000China Guangxi Medical University Nanning 530021Guangxi Zhuang Autonomous RegionChina

AIM:To investigate the frequency and associated factors of accommodation and non-strabismic binocular vision dysfunction among medical university ***:Totally 158 student volunteers underwent routine vision examination in the optometry clinic of Guangxi Medical *** data were used to identify the different types of accommodation and nonstrabismic binocular vision dysfunction and to determine their *** analysis and logistic regression were used to examine the factors associated with these ***:The results showed that 36.71%of the subjects had accommodation and non-strabismic binocular vision issues,with 8.86%being attributed to accommodation dysfunction and 27.85%to binocular *** insufficiency(CI)was the most common abnormality,accounting for 13.29%.Those with these abnormalities experienced higher levels of eyestrain(χ2=69.518,P<0.001).The linear correlations were observed between the difference of binocular spherical equivalent(SE)and the index of horizontal esotropia at a distance(r=0.231,P=0.004)and the asthenopia survey scale(ASS)score(r=0.346,P<0.001).Furthermore,the right eye's SE was inversely correlated with the convergence of positive and negative fusion images at close range(r=-0.321,P<0.001),the convergence of negative fusion images at close range(r=-0.294,P<0.001),the vergence facility(VF;r=-0.234,P=0.003),and the set of negative fusion images at far range(r=-0.237,P=0.003).Logistic regression analysis indicated that gender,age,and the difference in right and binocular SE did not influence the emergence of these ***:Binocular vision abnormalities are more prevalent than accommodation dysfunction,with CI being the most frequent *** binocular refractive disparity leads to more severe eyestrain symptoms.

关键词： optometry clinic non-strabismic binocular vision dysfunction college students convergence insufficiency

Evolution of soil DOM during thermal remediation below 100℃:concentration,spectral characteristics and complexation ability

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Frontiers of Environmental Science & Engineering 2024年第8期18卷 31-41页

作者： wan Huang Ziren wan Di Zheng Lifeng Cao Guanghe Li Fang Zhang State Key Joint Laboratory of Environment Simulation and Pollution Control State Environment Protection Key Laboratory of Microorganism Application and Risk ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China National Engineering Laboratory for Site Remediation Technologies Beijing 100015China

The impact of thermal remediation on soil function has drawn increasing *** far,as the most active fraction of soil organic matter,the evolution of dissolved organic matter(DOM)during the thermal remediation lacks in-depth investigation,especially for the temperatures value below 100℃.In this study,a series of soil thermal treatment experiments was conducted at 30,60,and 90℃ during a 90-d period,where soil DOM concentration increased with heating temperature and *** molecular weight,functional groups content and aromaticity of DOM all decreased during the thermal *** excitation-emission matrices(EEM)results suggested that humic acid-like substances transformed into fulvic acid-like substances(FIII/FV increased from 0.27 to 0.44)during the heating process,and five DOM components were further identified by *** change of DOM structures and components indicated the decline of DOM stability and hydrophilicity,and can potentially change the bioavailability and *** temperature also resulted in the decline of DOM complexation ability,which may be caused by the loss of binding sites due to the decrease of polar function groups,aromatic structures and hydrophilic *** study provides valuable information about the evolution of DOM during thermal remediation,which would potentially change the fate of metal ions and the effectiveness of the post-treatment technologies in the treated region.

关键词： Thermal remediation below 100℃ Heating temperature Soil DOM concentration DOM spectral characteristics Excitation-emission matrices(EEM) Complexation ability

Finite barrier bound state

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Light(Science & Applications) 2024年第4期13卷 664-671页

作者： Tao Liu Kai Bai Yicheng Zhang Duanduan wan Yun Lai C.T.Chan Meng Xiao Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education and School of Physics and Technology Wuhan University430072 WuhanChina. National Laboratory of Solid State Microstructures School of Physicsand Collaborative Innovation Center of Advanced MicrostructuresNanjing University210093 NanjingChina. Department of Physics The Hong Kong University of Science and TechnologyClear Water BayKowloon999077Hong KongChina. Wuhan Institute of Quantum Technology 430206 WuhanChina

A boundary mode localized on one side of a finite-size lattice can tunnel to the opposite side which results in unwanted *** wisdom tells that the tunneling probability decays exponentially with the size of the system which thus requires many lattice sites before eventually becoming negligibly *** we show that the tunneling probability for some boundary modes can apparently vanish at specific ***,similar to bound states in the continuum,a boundary mode can be completely trapped within very few lattice sites where the bulk bandgap is not even *** intriguingly,the number of trapped states equals the number of lattice sites along the normal direction of the *** provide two configurations and validate the existence of this peculiar finite barrier-bound state experimentally in a dielectric photonic crystal at microwave *** work offers extreme flexibility in tuning the coupling between localized states and channels as well as a new mechanism that facilitates unprecedented manipulation of light.

关键词： boundary state eventually

A columnar multi-layer sliding triboelectric nanogenerator for water wave energy harvesting independent of wave height and direction

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Nano Research 2024年第4期17卷 3029-3034页

作者： Xue Miao Hanxiao Yang Zekun Li Meifei Cheng Yilin Zhao Lingyu wan Aifang Yu Junyi Zhai Center on NanoEnergy Research School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Beijing Institute of Nano Energy and Nano Systems Chinese Academy of SciencesBeijing 101400China School of Nanoscience and Engineering University of Chinese Academy of ScienceBeijing 101408China

The ocean,with its highly variable and complex meteorological conditions,harbors enormous renewable *** nanogenerators(TENGs),which possess unique advantages,show exciting prospects in water wave energy *** to design and optimize TENGs to cover all characteristic water wave energies and achieve efficient energy utilization is *** this paper,we carefully designed and fabricated a columnar multi-layer sliding TENG(CMLS-TENG)that can harvest water wave energy independent of wave height and *** rods with a hollow acrylic spherical shell were introduced to deliver wave energy,ensuring that the CMLS-TENG can work in all directions from 0°to 360°.Based on the sliding structure,switching the optimized CMLS-TENG is independent of wave *** optimized CMLS-TENG can achieve a total power density of 730 mW/m^(3) at a wave height of only 4.8 cm regardless of wave direction,which can illuminate multiple light-emitting diodes(LEDs)to provide lighting and provide power to a watch and a hygrometer for temperature and humidity *** work provides new choices and hopes for the effective collection of full-range water wave energy.

关键词： triboelectric nanogenerator wave energy multi-direction columnar slide

Achieving Synergistic Improvement in Dielectric and Energy Storage Properties of All-Organic Poly(Methyl Methacrylate)-Based Copolymers Via Establishing Charge Traps

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Energy & Environmental Materials 2024年第2期7卷 308-319页

作者： Guanghu He Huang Luo Chuanfang Yan Yuting wan Dang Wu Hang Luo Yuan Liu Sheng Chen Key Laboratory of Polymeric Materials and Application Technology of Hunan Province College of ChemistryXiangtan UniversityXiangtan 411105China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Guangdong University of Petrochemical Technology Maoming 525000China

How to achieve synergistic improvement of permittivity(ε_(r))and breakdown strength(E_(b))is a huge challenge for polymer ***,for the first time,theπ-conjugated comonomer(MHT)can simultaneously promote theε_(r)and E_(b)of linear poly(methyl methacrylate)(PMMA)*** PMMA-based random copolymer films(P(MMA-co-MHT)),block copolymer films(PMMA-b-PMHT),and PMMA-based blend films were prepared to investigate the effects of sequential structure,phase separation structure,and modification method on dielectric and energy storage properties of PMMA-based dielectric *** a result,the random copolymer P(MMA-coMHT)can achieve a maximumε_(r)of 5.8 at 1 kHz owing to the enhanced orientation polarization and electron *** electron injection and charge transfer are limited by the strong electrostatic attraction ofπ-conjugated benzophenanthrene group analyzed by the density functional theory(DFT),the discharge energy density value of P(MMA-co-PMHT)containing 1 mol%MHT units with the efficiency of 80%reaches15.00 J cm^(-3)at 872 MV m^(-1),which is 165%higher than that of pure *** study provides a simple and effective way to fabricate the high performance of polymer dielectrics via copolymerization with the monomer of P-type semi-conductive polymer.

关键词： dielectric capacitor electrical properties energy density polymer dielectric semiconductor polymer

Peripheral carbazole units-decorated MR emitter containing B−N covalent bond for highly efficient green OLEDs with low roll-off

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Journal of Semiconductors 2024年第8期45卷 59-66页

作者： Danrui wan Jianping Zhou Guoyun Meng Ning Su Dongdong Zhang Lian Duan Junqiao Ding School of Chemical Science and Technology Yunnan UniversityKunming 650091China Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China Southwest United Graduate School Kunming 650092China

Boron−nitrogen doped multiple resonance(BN-MR)emitters,characterized by B−N covalent bonds,offer distinctive advantages as pivotal building blocks for facile access to novel MR emitters featuring narrowband spectra and high ***,there remains a scarcity of exploration concerning synthetic methods and structural derivations to expand the library of novel BN-MR ***,we present the synthesis of a BN-MR emitter,tCz[B−N]N,through a one-pot borylation reaction directed by the amine group,achieving an impressive yield of 94%.The emitter is decorated by incorporating two 3,6-di-tbutylcarbazole(tCz)units into a B−N covalent bond doped BN-MR parent molecule via para-C−π−D and para-N−π−D *** peripheral decoration strategy enhances the reverse intersystem crossing process and shifts the emission band towards the pure green region,peaking at 526 nm with a narrowband full-width at half maximum(FWHM)of 41 ***,organic light emitting diodes(OLEDs)employing this emitter achieved a maximum external quantum efficiency(EQEmax)value of 27.7%,with minimal efficiency *** at a practical luminance of 1000 cd·m^(−2),the device maintains a high EQE value of 24.6%.

关键词： multi-resonance narrowband emission B−N covalent bond organic light emitting diodes