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hardy Spaces Associated with Ball Quasi-Banach Function Spaces on Spaces of homogeneous Type:Littlewood–Paley Characterizations with Applications to Boundedness of Calderón–Zygmund Operators

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Acta Mathematica Sinica,English Series 2022年第7期38卷 1133-1184页

作者： Xian Jie YAN Zi Yi hE Da Chun yang Wen yuan Laboratory of Mathematics and Complex Systems(Ministry of Education of China) School of Mathematical SciencesBeijing Normal UniversityBeijing 100875P.R.China School of Science Beijing University of Posts and TelecommunicationsBeijing 100876P.R.China

Let(X,ρ,μ)be a space of homogeneous type in the sense of Coifman and Weiss,and Y(X)a ball quasi-Banach function space on X,which supports both a Fefferman–Stein vector-valued maximal inequality and the boundedness of the powered hardy–Littlewood maximal operator on its associate *** authors first introduce the hardy space h_(Y)(X)associated with Y(X),via the Lusin-area function,and then establish its various equivalent characterizations,respectively,in terms of atoms,molecules,and Littlewood–Paley g-functions and g_(λ)^(*)-*** an application,the authors obtain the boundedness of Calderón–Zygmund operators from h_(Y)(X)to Y(X),or to h_(Y)(X)via first establishing a boundedness criterion of linear operators on h_(Y)(X).All these results have a wide range of generality and,particularly,even when they are applied to variable hardy spaces,the obtained results are also *** major novelties of this article exist in that,to escape the reverse doubling condition ofμand the triangle inequality ofρ,the authors subtly use the wavelet reproducing formula,originally establish an admissible molecular characterization of h_(Y)(X),and fully apply the geometrical properties of X expressed by dyadic reference points or dyadic cubes.

关键词： ball quasi-Banach function space hardy space space of homogeneous type Littlewood-Paley function Calderón-Zygmund operator

Palladium-catalyzed cascade synthesis of spirocyclic oxindoles via regioselective C2-h arylation and C8-h alkylation of naphthalene ring

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Chinese Chemical Letters 2021年第2期32卷 713-716页

作者： Xiai Luo Wenguang Li haiyan Lu Guobo Deng yuan yang Chunming yang Yun Liang National&Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources Key Laboratory of Chemical Biology and Traditional Chinese Medicine ResearchMinistry of EducationKey Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan ProvinceCollege of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha 410081China hunan University of Medicine Huaihua 418000China

A simultaneous C2-h arylation and C8-h alkylation of naphthalene ring has been achieved by palladiumcatalyzed cascade reaction of N-(2-halophenyl)-2-(naphthalen-1-yl)acrylamides with aryl iodides,which provides an efficient method for synthesizing various aryl-substituted spirocyclic *** protocol enables three C-C bonds formation via an intramolecular heck reaction and sequentially regioselective C-h bond activation.

关键词： Palladium-catalyzed Cascade reaction Regioselective C-h activation Naphthalene ring Spirocyclic oxindoles

Construction of NIR luminescent nanoscale lanthanide complexes with new flexible Schiff base ligands

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Journal of Rare Earths 2020年第2期38卷 143-147页

作者： Bichen yuan Junbin Tao Fei Wang Chaoqun Zhu Min Li Xiaoping yang Zhejiang Key Laboratory of Carbon Materials College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China

Four mono-and bi-nuclear lanthanide complexes [LnL1(No3)(h2O)DMF](Ln=Nd(1) and Yb(2)) and[Ln2(L2)2(OAc)2](Ln=Nd(3) and Yb(4)) were synthesized by using two new Schiff base ligands with long(Ch2)2 Nh(Ch2)2 *** lengths of the Schiff base ligands are about 1.8 *** bi-nuclear lanthanide complexes 3 and 4 have nanoscale structures with sizes of approximately 0.7 nm×1.1 nm×1.6 *** 3,the molar ratio of Nd:Br:O obtained by the energy dispersive X-ray spectroscopy analysis is in agreement with the crystal *** chromogenic Schiff base ligands in1-4 can efficiently transfer energy to lanthanide ions,thus,these complexes exhibit the typical NIR luminescence of lanthanide ***,3 and 4 have higher NIR emission quantum yields(Φem)than 1 and 2,respectively.

关键词： Construction Schiff base ligands Lanthanide complexes Nanoscale structures NIR luminescence Rare earths

Tuning the porosity of {Co12IICo8III（μ3-Oh）24（X）}11+ supramolecular frameworks by reaction time for D2/h2 separation

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Science China Chemistry 2025年

作者： Zhuozhou Xie Zhu Zhuo Zi-Ang Nan Qing Li Xiufang Li Zi-Xiu Lu Linzhe Lü Jin Liu Luyao Liu Wenjing Wang Wei Wang Daqiang yuan You-Gui huang State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth Materials Haixi InstitutesChinese Academy of Sciences State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical EngineeringXiamen University

Systematicly tuning the porosities of porous materials is crucial for targeted gas mixture separation,yet it remains a longstanding *** a common strategy,altering the phenylene ring count in the organic building units has been exploited to adjust pore apertures in metal organic frameworks （MOFs） and covalent organic frameworks （COFs）,resulting in only a stepwise pore size variation of approximately 2.8?.Unlike MOFs and COFs,the porosities for supramolecular assembly frameworks are highly dependent on the packings of the molecular building units in the *** above strategy cannot be applied to supramolecular assembly frameworks and other strategies are required to adjust pore apertures in supramolecular frameworks,especially to achieve porous materials with the optimal pore size for D2/h2separation （～3?）.here,we successfully modulate the porosity of supramolecular frameworks of[CoII1+12CoIII8L12（μ3-Oh）24（X）]1clusters （L=mono-deprotonated 1-iminoisoindole-3-amine,X=ClO?4or Cl?） by controlling the duration of self-assembly *** simply adjusting the reaction time,we obtain three[CoII12CoIII8L12（μ3-Oh）24（X）]11+supramolecular frameworks:[CoII12CoIII8（μ3-Oh）24（ClO4）L12)]·（Cl）4·（hCO2）7（1）,[CoII12CoIII8L12（μ3-Oh）24（Cl）]·（ClOI4）4·（Cl）6·（hCO2）·（h2O）10（2）,and[CoI12CoIII8L12（μ3-Oh）24（Cl）]·（Cl）11·（h2O）12（3）.The different stacking patterns of the[CoII12CoIII8L12（μ3-Oh）24（X）]11+clusters in these frameworks lead to significantly varied stabilities and *** 1 exhibits permanent porosity with interconnected channels and maintains stability under harsh *** contrast,compound 2 is nearly nonporous,and compound 3 becomes unstable upon *** pores of compound 1 show higher affinity to D2than h2,and the pore aperture diameter of compound 1 （～3.06?） meets the optimal porosity for D2/***,compound 1 demonstrates moderate D2/h2separation at 77 K (retention time:～7 min/g for D2/h2/Ne （10/10/80 vol%） in a flow of 5 mL

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Einstein Probe discovery of EP240408a: A peculiar X-ray transient with an intermediate timescale

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 222-240页

作者： Wenda Zhang Weimin yuan Zhixing Ling Yong Chen Nanda Rea Arne Rau Zhiming Cai huaqing Cheng Francesco Coti Zelati Lixin Dai Jingwei hu Shumei Jia Chichuan Jin Dongyue Li Paul O’Brien Rongfeng Shen Xinwen Shu Shengli Sun Xiaojin Sun Xiaofeng Wang Lei yang Bing Zhang Chen Zhang Shuang-Nan Zhang Yonghe Zhang Jie An David Buckley Alexis Coleiro Bertrand Cordier Liming Dou Rob Eyles-Ferris Zhou Fan hua Feng Shaoyu Fu Johan P.U.Fynbo Lluis Galbany Saurabh W.Jha Shuaiqing Jiang Albert Kong Erik Kuulkers Weihua Lei Wenxiong Li Bifang Liu Mingjun Liu Xing Liu yuan Liu Zhu Liu Chandreyee Maitra Alessio Marino Itumeleng Monageng Kirpal Nandra Jeremy Sanders Roberto Soria Lian Tao Junfeng Wang Song Wang Tinggui Wang Zhongxiang Wang Qingwen Wu Xuefeng Wu Dong Xu Yanjun Xu Suijian Xue Yongquan Xue Zijian Zhang Zipei Zhu hu Zou Congying Bao Fansheng Chen houlei Chen Tianxiang Chen Wei Chen Yehai Chen Yifan Chen Chenzhou Cui Weiwei Cui Yanfeng Dai Dongwei Fan Ju Guan Dawei han Dongjie hou haibo hu Maohai huang Jia huo Zhenqing Jia Bowen Jiang Ge Jin Chengkui Li Junfei Li Longhui Li Maoshun Li Wei Li Zhengda Li Tianying Lian Congzhan Liu heyang Liu huaqiu Liu Fangjun Lu Laidan Luo Jia Ma Xuan Mao haiwu Pan Xin Pan Liming Song hui Sun Yunyin Tan Qingjun Tang Yihan Tao hao Wang Juan Wang Lei Wang Wenxin Wang Yilong Wang Yusa Wang Qinyu Wu haitao Xu Jingjing Xu Xinpeng Xu Yunfei Xu Zhao Xu Changbin Xue Yulong Xue Ailiang Yan haonan yang Xiongtao yang Yanji yang Juan Zhang Mo Zhang Wenjie Zhang Zhen Zhang Zhen Zhang Ziliang Zhang Donghua Zhao haisheng Zhao Xiaofan Zhao Zijian Zhao hongyan Zhou Yilin Zhou Yuxuan Zhu Zhencai Zhu National Astronomical Observatories Chinese Academy of Sciences School of Astronomy and Space Sciences University of Chinese Academy of Sciences Key Laboratory of Particle Astrophysics Institute of high Energy Physics Chinese Academy of Sciences Institute of Space Sciences (ICE) CSIC Institut d’Estudis Espacials de Catalunya (IEEC) Max Planck Institute for Extraterrestrial Physics Innovation Academy for Microsatellites Chinese Academy of Sciences Department of Physics University of hong Kong School of Physics and Astronomy University of Leicester School of Physics and Astronomy Sun Yat-sen University Department of Physics Anhui Normal University Shanghai Institute of Technical Physics Chinese Academy of Sciences Physics Department Tsinghua University Nevada Center for Astrophysics University of Nevada Las Vegas Department of Physics and Astronomy University of Nevada Las Vegas South African Astronomical Observatory Department of Astronomy University of Cape Town Department of Physics University of the Free State Université Paris Cité CNRS Astroparticule et Cosmologie Université Paris Cité CEA Paris-Saclay IRFU/DAp-AIM Department of Astronomy Guangzhou University Cosmic Dawn Center (DAWN) Niels Bohr Institute University of Copenhagen Department of Physics and Astronomy Rutgers the State University of New Jersey Institute for Cosmic Ray Research The University of Tokyo ESA/ESTEC Department of Astronomy School of Physics huazhong University of Science and Technology INAF-Osservatorio Astrofisico di Torino Sydney Institute for Astronomy School of Physics The University of Sydney Department of Astronomy Xiamen University Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University Department of Astronomy University of Science and Technology School of Astronomy and Space Sciences University of Science and Technology of China Institute of Deep Space Sciences Deep Space Exploration Laboratory Department of Astronomy School of Physics and Astronomy Yunnan University Shanghai Astronomical Observatory Chi

We report the discovery of a peculiar X-ray transient,EP240408a,by Einstein Probe （EP） and follow-up studies made with EP,Swift,NICER,GROND,ATCA and other ground-based multiwavelength *** new transient was first detected with Wide-field X-ray Telescope （WXT） on board EP on April 8th,2024,manifested in an intense yet brief X-ray flare lasting for *** flare reached a peak flux of 3.9×10-9erg cm-2s-1in 0.5-4 ke V,～300 times brighter than the underlying X-ray emission detected throughout the *** and more precise follow-up observations by EP/FXT,Swift and NICER confirmed the finding of this new *** X-ray spectrum is non-thermal in 0.5-10 ke V,with a power-law photon index varying *** X-ray light curve shows a plateau lasting for ～4 d,followed by a steep decay till becoming undetectable ～10 d after the initial *** on its temporal property and constraints from previous EP observations,an unusual timescale in the range of 7-23 d is found for EP240408a,which is intermediate between the commonly found fast and long-term *** counterparts have been found in optical and near-infrared,with the earliest observation at 17 h after the initial X-ray detection,suggestive of intrinsically weak emission in these *** demonstrate that the remarkable properties of EP240408a are inconsistent with any of the transient types known so far,by comparison with,in particular,jetted tidal disruption events,gamma-ray bursts,X-ray binaries and fast blue optical *** nature of EP240408a thus remains an *** suggest that EP240408a may represent a new type of transients with intermediate timescales of the order of～10 *** detection and follow-ups of more of such objects are essential for revealing their origin.

关键词： X-ray transients ${\bm~{Einstein~~Probe}}$

Effect of Mg/Al Ratios on hydration Mechanism of Tabular Alumina Carbon Composites Reinforced by Al4C3 in situ Reaction

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Journal of Wuhan University of Technology(Materials Science) 2017年第4期32卷 800-805页

作者：杨依帆 JIANG Mingxue yang Ding'ao yuan Shouqian ZhAO Jizeng ZhAO Wei yang Mengyao College of Materials and Mineral Resources Xi'an University of Architecture and TechnologyXi'an 710055China Beijing Lier high-Temperature Materials Co. LtdBeijing 102211China Fuzhou University Zhicheng College Fuzhou 350002China

hydration mechanism of tabular alumina carbon composites reinforced by Al4C3 in situ reaction with Mg and Al was researched in water steam using super automatic thermostatic water bath from 25 ℃ to 85 ℃. It is shown that hydration mechanism of the composites is chemical reaction control at 44.3 ℃-84 ℃ in h2O（g）. The hydration was controlled by diffusion from 24.7 ℃ to 33 ℃. The ratio of added Mg/Al influences the hMOR of the *** mechanism of hMOR of the composites with different ratios of Mg/Al can be discovered by means of SEM analysis. The active Mg/Al powder and flake graphite inside give the composites outstanding hot strength resulting from the interlocking structure of Al4C3 crystals at high temperature. Besides, the matrix changes into the Al4C3 with high refractoriness. The method of preventing the hydration of tabular alumina carbon composites reinforced by Al4C3 in situ reaction was immersed in the wax at suitable temperature or storing them below 33 ℃ in a dry place or storing them with paraffin-coating.

关键词： hydration mechanism tabular alumina carbon Al4C3 Mg/Al ratios

Sample spinning to mitigate polarization artifact and interstitial-vacancy imbalance in ion-beam irradiation

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npj Computational Materials 2020年第1期6卷 107-117页

作者： Cui-Lan Ren yang yang Yong-Gang Li Ping huai Zhi-yuan Zhu Ju Li Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Department of Nuclear Science and Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA Key Laboratory of Interfacial Physics and Technology Chinese Academy of SciencesShanghai 201800China National Center for Electron Microscopy Molecular FoundryLawrence Berkeley National LaboratoryBerkeleyCA 94720USA Key Laboratory of Materials Physics Institute of Solid State PhysicsChinese Academy of SciencesHefei 230031China Science Island Branch of Graduate School University of Science and Technology of ChinaHefei 230026China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteShanghai 201204China Department of Materials Science and Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA

Accelerator-based ion-beam irradiation has been widely used to mimic the effects of neutron radiation damage in nuclear ***,ion radiation is most often monodisperse in the incoming ions’momentum direction,leading to excessive polarization in defect distribution,while the scattering under neutron irradiation is often more isotropic and has less radiation-induced *** of the excess-polarization as well as the damage non-uniformity artifact might be crucial for making the simulation of neutron radiation by ion-beam radiation more *** this work,a general radiation polarization theory in treating radiation as external polar stimuli is established to understand the natural material responses in different contexts,and the possibility to correct the defect polarization artifact in ion-beam *** by Magic Angle Spinning in Nuclear Magnetic Resonance,we present a precise sample spinning strategy to reduce the point-defect imbalance effect in ion-beam *** can be seen that with optimized surface inclination angle and the axis of sample rotation,the vacancy-interstitial population imbalance,as well as the damage profile non-uniformity in a designated region in the target are both *** is estimated that sample spinning frequency on the order of khz should be sufficient to scramble the ion momentum monodispersity for commonly taken ion fluxes and dose rates,which is experimentally feasible.

关键词： beam vacancy momentum

Insect group II chitinase OfChtll promotes chitin degradation during larva-pupa molting

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Insect Science 2021年第3期28卷 692-704页

作者： Ming-Bo Qu Shao-Peng Sun yuan-Sheng Liu Xiao-Rui Deng Jun yang Qing yang School of Bioengineering Dalian University of TechnologyDalianLiaoningChina State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection and Shenzhen Agricultural Genome Research InstituteChinese Academy of Agricultural SciencesBeijingChina

The insect group ll chitinase(ChtIl,also known as Cht10)is a unique chitinasewith multiple catalytic and chitin-binding *** has been proven genetically to be anessential chitinase for ***,Chtll's role in chitin degradation during insectdevelopment remains poorly *** this knowledge is the key to fullyunderstanding the chitin degradation system in ***,we investigated the roleof OfChtll during the molting of Ostrinia furnacalis,a model lepidopteran pest *** was expressed earlier than OfChtI(OfCht5)and OfChi-h,at both the gene andprotein levels during larva-pupa molting as evidenced by quantitative polymerase chainreaction and western blot analyses.A truncated OfChtII,OfChtII-B4C1,was recombinantlyexpressed in Pichia pastoris cells and purified to *** recombinant OfChtll-B4C1 loosened compacted chitin particles and produced holes in the cuticle surface asevidenced by scanning electron *** synergized with OfChtl and OfChi-h whenhydrolyzing insoluble *** findings suggested an important role for ChtIl duringinsect molting and also provided a strategy for the coordinatdd degradation of cuticularchitin during insect molting by Chtll,Chtl and Chi-h.

关键词： chitin chitinase chitin binding degradation multiple module synergy

RuNi Alloy Nanoparticles Encapsulated in Oxygen-Doped Carbon as Bifunctional Catalyst towards hydrogen Electrocatalysis

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Chinese Journal of Chemistry 2021年第12期39卷 3455-3461页

作者： Qing yuan yang yang Shipeng Gong Shi Chen Minxue huang Changlai Wang huigang Tong Qianwang Chen hefei National Laboratory for Physical Science at Microscale and Department of Materials Science&Engineering University of Science and Technology of ChinaHefeiAnhui 230026China

The efficient production and utilization of hydrogen play an important role in the closed loop of energy *** is an urgent need to find low-cost and high-performance replacements for platinum-based catalysts towards hydrogen oxidation reaction(hOR)and hydrogen evolution reaction(hER).herein,bifunctional RuNi alloy nanoparticles embedded in oxygen-doped carbon were pre-pared via simple annealing of Ru-doped Ni-BTC,the limiting current density of which could reach 2.46 mA/cm^(2)(close to Pt)in 0.1 mol/L KOh for *** the low overpotentials of only 29 mV in 1 mol/L KOh and 62 mV in 0.5 mol/L h_(2)SO_(4) were needed to reach the current density of 10 mA/cm^(2) for *** effect of alloying and oxygen-doped graphene contributed to the excellent activity and stability during hydrogen *** work provides new ideas for the development of novel types of hydrogen electrocatalysts and enriches the application of MOFs in hOR.

关键词： Electrocatalysts Water splitting hydrogen oxidation reaction Metal-organic frameworks Nanoparticles