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Chinese Chemical Letters 2024年第5期35卷 135-140页

作者： Zhen liu Zhi-Yuan ren Chen Yang Xiangyi Shao li Chen Xin li State Key Laboratory of Elemento-Organic Chemistry Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhenhai High School of Zhejiang Ningbo 315299China

Catalytic enantioselective alkenylation is an efficient method to construct chiral alkene molecules,but the asymmetric alkenylation of simple alkenes catalyzed by metal-free catalysts remains an elusive ***,we reported an asymmetric alkenylation of benzoxazinones with diarylethylenes by utilizing a B(C_(6)F_(5))_(3)/chiral phosphoric acid catalyst.A broad of benzoxazinones and diarylethylenes with electron-withdrawing and electron-donating groups were tolerated(up to 95%yield and 97.5:2.5 e.r.)in the methodology under mild reaction ***,the synthetic utility was confirmed by the scaled-up reaction and transformations of the *** mechanism was preliminarily explored by control reactions,nonlinear effect experiment and DFT calculations.

关键词： Asymmetric alkenylation Simple alkenes Benzoxazinones B(C_(6)F_(5))_(3)/chiral phosphoric acid Theoretical calculations

Characteristics and Preliminary Causes of Tropical Cyclone Remote Precipitation over China

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Journal of Ocean University of China 2024年第4期23卷 845-858页

作者： JIA li ren Fumin MCBRIDE John Leonard CONG Chunhua School of Atmospheric Science Nanjing University of Information Science and TechnologyNanjing 210044China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China School of Earth Science University of MelbourneMelbourne 3052Australia Research and Development Division Bureau of MeteorologyMelbourne 3052Australia Shandong Meteorological Bureau Jinan 250031China

In this study,the characteristics and preliminary causes of tropical cyclone remote precipitation(TRP)over China during the period from 1979 to 2020 are *** indicated that approximately 72.42%of tropical cyclones(TCs)in the Western Pacific produce TRP over *** peak months for TRP are July and *** four key regions of TRP are the adjacent areas between the Sichuan and Shaanxi Provinces,the northern coast of the Bohai Sea,the coast of the Yellow Sea,and the southern coast *** typical distance between the station with TRP and the TC center ranges from 1500 to 2500 *** of these stations are situated north to 60°west of north of the *** south–west water vapor transportation on the west side of the TC is crucial to *** has a decreasing trend because of the decrease in the number of TCs that generate *** the perspective of large-scale environmental conditions,a decrease in the integrated horizontal water vapor transport in China' Mainland,the weakening of upward motion at approximately 25°–35°N,which is inconducive to convection,and an increase in low-level vertical wind shear,which is unfavorable for the development of TC in areas with high frequencies of TRP-related TCs,are the factors that result in the decreasing trend of TRP.

关键词： tropical cyclone remote precipitation characteristics causes

Solidification crack characteristics and sensitivity of peritectic steel

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Journal of Iron and Steel Research International 2024年第7期31卷 1668-1679页

作者： Ya-qiang li Jian-hua liu Zi-ming Wang Ying-ying li Yang He Xiao-wei li Department of Automotive Engineering Hebei Vocational University of Technology and EngineeringXingtai 054000HebeiChina Hebei Special Vehicle Modification Technology Innovation Center Hebei Vocational University of Technology and EngineeringXingtai 054000HebeiChina Institute of Engineering Technology University of Science and Technology BeijingBeijing 100083China School of Petroleum and Natural Gas Engineering Changzhou UniversityChangzhou 213164JiangsuChina

The characteristics and sensitivity of solidification cracks in peritectic steels were investigated using directional solidifi-cation *** cracks were observed in both hypoperitectic steels(12CrlMoV,15CrMo)and hyper-peritectic steel(20CrMo)during solidification at growth velocities of 15,50,and 80 pm/*** the dendritic boundaries,sulphide precipitates were found,promoting crack *** on the statistical analysis of interdendritic cracks in peritectic steels,the area ratio(RA)of interdendritic cracks in a directional solidification structure was proposed to evaluate the crack sensitivity of peritectic ***,the crack sensitivities of peritectic steels(12CrlMoV,15CrMo,and 20CrMo)were tested,evaluated,and compared with the surface crack rates of three types of steels produced from a steel *** results demonstrated that RA was in good agreement with that of the steel plant,and the crack sensitivity of 12CrlMoV steel was the strongest,followed by that of 15CrMo and 20CrMo ***,RA can be used to evaluate the crack sensitivity of peritectic steel.

关键词： Peritectic steel-Directional solidification Growth velocity Dendritic structure Solidification crack Crack sensitivity

Microstructures and micromechanical behaviors of high -entropy alloys investigated by synchrotron X-ray and neutron diffraction techniques: A review

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1333-1349页

作者： Yubo huang Ning Xu huaile Lu Yang ren Shilei li Yandong Wang Beijing Advanced Innovation Center of Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China AnSteel Beijing Research Institute Co.Ltd. Beijing 102200China Spallation Neutron Source Science Center Dongguan 523803China Department of Physics City University of Hong KongHong Kong 999077China Institute for Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

High-entropy alloys(HEAs)possess outstanding features such as corrosion resistance,irradiation resistance,and good mechan-ical properties.A few HEAs have found applications in the fields of aerospace and *** studies on the deformation mech-anisms of HEAs can guide microstructure control and toughness design,which is vital for understanding and studying state-of-the-art structural *** X-ray and neutron diffraction are necessary techniques for materials science research,especially for in situ coupling of physical/chemical fields and for resolving macro/microcrystallographic information on ***,several re-searchers have applied synchrotron X-ray and neutron diffraction methods to study the deformation mechanisms,phase transformations,stress behaviors,and in situ processes of HEAs,such as variable-temperature,high-pressure,and hydrogenation *** this review,the principles and development of synchrotron X-ray and neutron diffraction are presented,and their applications in the deformation mechanisms of HEAs are *** factors that influence the deformation mechanisms of HEAs are also *** review fo-cuses on the microstructures and micromechanical behaviors during tension/compression or creep/fatigue deformation and the application of synchrotron X-ray and neutron diffraction methods to the characterization of dislocations,stacking faults,twins,phases,and intergrain/interphase stress *** on future developments of synchrotron X-ray and neutron diffraction and on research directions on the deformation mechanisms of novel metals are discussed.

关键词： high-entropy alloys microstructures micromechanical behaviors synchrotron X-ray diffraction neutron diffraction

Mogroside IIE,an in vivo metabolite of sweet agent,alleviates acute lung injury via Pla2g2a-EGFR inhibition

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Food Science and Human Wellness 2024年第1期13卷 299-312页

作者： Weichao Lü Guoqing ren Kuniyoshi Shimizu renshi li Chaofeng Zhang State Key Laboratory of Natural Medicines School of Traditional Chinese PharmacyChina Pharmaceutical UniversityNanjing 211198China Sino-Jan Joint Lab of Natural Health Products Research School of Traditional Chinese PharmacyChina Pharmaceutical UniversityNanjing 211198China Faculty of Agriculture Kyushu UniversityFukuoka 819-0395Japan

In the face of increasingly serious environmental pollution,the health of human lung tissues is also facing serious *** IIE(M2E)is the main metabolite of sweetening agents mogrosides from the anti-tussive Chinese herbal Siraitia *** study elucidated the anti-inflammatory action and molecular mechanism of M2E against acute lung injury(Ali).A lipopolysaccharide(LPS)-induced Ali model was established in mice and MH-S cells were employed to explore the protective mechanism of M2E through the western blotting,co-immunoprecipitation,and quantitative real time-PCR *** results indicated that M2E alleviated LPS-induced lung injury through restraining the activation of secreted phospholipase A2 type IIA(Pla2g2a)-epidermal growth factor receptor(EGFR).The interaction of Pla2g2a and EGFR was identified by *** addition,M2E protected Ali induced with LPS against inflammatory and damage which were significantly dependent upon the downregulation of AKT and m TOR via the inhibition of ***2g2a may represent a potential target for M2E in the improvement of LPS-induced lung injury,which may represent a promising strategy to treat Ali.

关键词： Mogroside IIE Acute lung injury Secreted phospholipase A2 type IIA(Pla2g2a) Epidermal growth factor receptor(EGFR)

Distribution of polarization squeezed light through a 20 km fiber channel

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Science China(Information Sciences) 2024年第5期67卷 343-344页

作者： Chao li Siyu ren Yanru YAN Yalin li Meihong WANG Xiaolong SU State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-Electronics Shanxi University Collaborative Innovation Center of Extreme Optics Shanxi University

Polarization squeezed light plays a key role in quantum memory by transferring quantum information between atoms and photons [1], and has potential applications in quantum precision measurement [2]. For polarization squeezed light, the quantum variance of at least one Stokes operator is smaller than that of the coherent *** with the quadrature squeezed state, polarization squeezed light has the following advantages: one is that it is a bright beam, and the other is that it can be measured directly without using a local oscillator.

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Nickel-Catalyzed Stereoselective Migratory Carboboration of 1,4-Cyclohexadiene

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Chinese Journal of Chemistry 2024年第4期42卷 356-362页

作者： Yaoyu ren Lujin Wang Chao Ding Yangyang li Guoyin Yin The Institute for Advanced Studies Wuhan UniversityWuhanHubei430072 China

Multi-substituted cyclohexanes play a crucial role as scaffolds in bioactive *** significant progress has been made in synthesizing substituted cyclohexanes,methods for the stereoselective assembly of 1,3-disubstituted cyclohexanes remain *** study presents a novel approach involving nickel catalysis to achieve stereoselective carboboration of 1,*** innovative process allows for the simultaneous introduction of a boron group and an aryl or an alkyl fragment into the 1,4-cyclohexadiene framework under mild conditions,with exclusive regioselectivity and excellent cis *** resulting products feature a double carbon bond and the incorporation of the boron group,offering significant potential for subsequent transformations and downstream applications.

关键词： 1,4-Cyclohexadiene Carboboration Nickel Chain-walking Stereoselectivity Difunctionalization

Dealuminated Hβ zeolite for selective conversion of fructose to furfural and formic acid

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Green Energy & Environment 2024年第2期9卷 311-320页

作者： Rui li Qixuan lin Junli ren Xiaobao Yang Yingxiong Wang lingzhao Kong State Key Laboratory of Pulp and Paper Engineering School of Light Industry and EngineeringSouth China University of TechnologyGuangzhou510640China Institute of Coal Chemistry Chinese Academy of Sciences27 South Taoyuan RoadTaiyuan030001China CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai201210China School of Environmental Science and Technology Suzhou University of Science and Technology Suzhou Jiangsu215009China

The fructose-to-furfural transformation is facing major challenges in the selectivity and high efficiency. Herein, we have developed a simple and effective approach for the selective conversion of fructose to furfural using Hβ zeolite modified by organic acids for dealuminization to regulate its textural and acidic properties. It was found that citric acid-dealuminized Hβ zeolite possessed high specific surface areas, wide channels and high Brønsted acid amount, which facilitated the selective conversion of fructose to furfural with a maximum yield of 76.2% at433 K for 1 h in the γ-butyrolactone(GBL)-H_(2)O system, as well as the concomitant formation of 83.0% formic acid. The^(13)C-isotope labelling experiments and the mechanism revealed that the selective cleavage of C1–C2 or C5–C6 bond on fructose was firstly occurred to form pentose or C5 intermediate by weak Brønsted acid, which was then dehydrated to furfural by strong Brønsted acid. Also this dealuminized Hβ catalyst showed the great recycling performance and was active for the conversion of glucose and mannose.

关键词： Fructose Dealuminated-Hb zeolite Selective conversion Furfural

Recent progress in CdS-based S-scheme photocatalysts

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Journal of Materials Science & Technology 2024年第4期171卷 162-184页

作者： Yajing ren Yunfeng li Guixu Pan Ning Wang Yan Xing Zhenyi Zhang College of Environmental and Chemical Engineering Xi’an Polytechnic UniversityXi’an 710048China Jilin Provincial Key Laboratory of Advanced Energy Materials Department of ChemistryNortheast Normal UniversityChangchun 130024China Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian 116600China

Photocatalytic technology with sunlight as driving force can convert solar energy into other energy sources for storage and further *** sulfide(CdS),as a typical reducing semiconductor of metal sulfides,represents an interesting research hotspot in photocatalysis due to its suitable bandgap(2.4 eV)for utilizing visible light and strong reducing ability for inducing surface catalytic ***,the photocatalytic performance of CdS is still limited by its fast carrier recombination and serious *** far,CdS semiconductor has been widely developed as a typical reducing photocatalyst in constructing novel S-scheme heterojunction to overcome the above *** this review,the de-sign concepts,basic principles,and charge transfer characteristics of CdS-based S-scheme heterojunction photocatalysts have been comprehensively *** advanced and effective characterization methods for studying the mechanism of CdS-based S-scheme heterojunction are analyzed in ***-thermore,we also summarize the typical applications of CdS-based S-scheme heterojunctions for water splitting,CO_(2) reduction,pollutant degradation,***,according to the current investigation sta-tus,some drawbacks in the current synthetic strategy,mechanism exploration,and application prospect of CdS-based S-scheme heterojunction are proposed,which need to be addressed by further expansion and innovative research.

关键词： Photocatalysis CdS semiconductor Heterojunction S-scheme Metal sulfide

Optical scattering imaging with sub-nanometer precision based on position-ultra-sensitive giant Lamb shift

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 96-105页

作者： Zeyang liao Yu-Wei Lu Wei li Xue-hua Wang State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSun Yat-sen UniversityGuangzhou 510275China Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area(Guangdong) Shenzhen 518045China

The Lamb shift of a quantum emitter in close proximity to a plasmonic nanostructure can be three or more orders of magnitude larger than that in the free space and is ultra-sensitive to the emitter position and *** demonstrate that this large Lamb shift can be sensitively observed from the scattering or absorption spectrum dip shift of the coupled system when the plasmonic nanoparticle or tip scans the *** these observations,we propose a scanning optical scattering imaging method based on the plasmonic-enhanced Lamb shift with achieves sub-nanometer *** method is based on the scattering or absorption spectrum of the plasmon-emitter coupling system,which is free of the fluorescence quenching problem and easier to implement in a plasmon-emitter coupling *** addition,our scheme works even if the quantum emitter is slightly below the dielectric surface,which can bring about broader applications,such as detecting atoms and molecules or quantum dots above or under a surface.

关键词： Lamb shift plasmon optical scattering imaging