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Science China Chemistry 2024年第11期67卷 3833-3843页

作者： Zhaodong zhu Jingjing wu Frontiers Science Center for Transformative Molecules Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs School of Chemistry and Chemical Engineering Zhangjiang Institute for Advanced Study Shanghai Jiao Tong University

Based on rational design, benzoyl cyanide, a well-known ionic acylating reagent, has been developed as a general radical acylating reagent for benzylic site-selective acylation reactions for the first time. Using visible-light photoredox-catalyzed single electron transfer(SET) and hydrogen atom transfer(hAT) strategies, two different direct benzylic C–h acylation reactions with high atom economy have been developed. This newly developed radical acylating reagent could also be used to achieve three component acyltrifluoromethylation of styrenes, which is usually challenging to achieve by other means. All of these reactions proceed under mild nickel-free and NhC-free conditions with high functional group tolerance. In addition, based on our detailed mechanistic experiments, the process of radical-radical cross-coupling mechanism was suggested for these transformations.

关键词： photoredox catalysis benzylic C–h acylation radical acylating reagent hAT catalysis acyltrifluoromethylation

Topological Stability and Entropy for Certain Set-valued Maps

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Acta Mathematica Sinica,English Series 2024年第4期40卷 962-984页

作者： Yu ZhANG Yu Jun zhu School of Mathematical Sciences Xiamen UniversityXiamen 361005P.R.China

In this paper,the dynamics(including shadowing property,expansiveness,topological stability and entropy)of several types of upper semi-continuous set-valued maps are mainly considered from differentiable dynamical systems points of *** is shown that(1)if f is a hyperbolic endomorphism then for eachε>0 there exists a C^(1)-neighborhood U of f such that the induced set-valued map F_(f,U)has theε-shadowing property,and moreover,if f is an expanding endomorphism then there exists a C^(1)-neighborhood U of f such that the induced set-valued map F_(f,U)has the Lipschitz shadowing property;(2)when a set-valued map F is generated by finite expanding endomorphisms,it has the shadowing property,and moreover,if the collection of the generators has no coincidence point then F is expansive and hence is topologically stable;(3)if f is an expanding endomorphism then for eachε>0 there exists a C^(1)-neighborhood U of f such that h(F_(f,U,ε))=h(f);(4)when F is generated by finite expanding endomorphisms with no coincidence point,the entropy formula of F is ***,the dynamics of the set-valued maps based on discontinuous maps on the interval are also considered.

关键词： Set-valued map orbit space hyperbolic endomorphism perturbation shadowing expansiveness topological stability entropy

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Maximal operators of pseudo-differential operators with rough symbols

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 174-180页

作者： Ramla Benhamoud zhu Xiang-rong School of Mathematical Sciences Zhejiang Normal UniversityJinhua 321004China

Consider a pseudo-differential operator T_(a)f(x)=∫_(R^(n))e^(ix,ζ)a(x,ζ)f(ζ)dζwhere the symbol a is in the rough hormander class L^(∞)S_(ρ)^(m)with m∈R andρ∈[0,1].In this note,when 1≤p≤2,if n(ρ-1)/p and a∈L^(∞)S_(ρ)^(m),then for any f∈S(R^(n))and x∈R^(n),we prove that M(T_(a)f)(x)≤C(M(|f|^(p))(x))^(1/p) where M is the hardy-Littlewood maximal *** theorem improves the known results and the bound on m is sharp,in the sense that n(ρ-1)/p can not be replaced by a larger constant.

关键词： pseudo-differential operator rough hormander class h-L maximal operator

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Reactive destabilization and bidirectional catalyzation for reversible hydrogen storage of LiBh_(4) by novel waxberry-like nano-additive assembled from ultrafine Fe_(3)O_(4) particles

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Journal of Materials Science & Technology 2024年第6期173卷 63-71页

作者： S.wang M.h.wu Y.Y.zhu Z.L.Li Y.X.Yang Y.Z.Li h.F.Liu M.X.Gao Department of Material Science Shenzhen MSU-BIT UniversityShenzhen 518172China State Key Laboratory of Silicon and Advanced Semiconductor Materials&School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China Institute of Resources Utilization and Rare Earth Development State Key Laboratory of Rare Metals Separation and Comprehensive UtilizationGuangdong Provincial Key Laboratory of Rare Earth Development and ApplicationGuangdong Academy of SciencesGuangzhou 510650China Institute of Science and Technology for New Energy Xi’an Technological UniversityXi’an 710021China National Supercomputing Center in Shenzhen Shenzhen 518055China

LiBh_(4) containing 18.5 wt.%h_(2) is an attractive high-capacity hydrogen storage material,however,it suffers from high operation temperature and poor ***,a novel and low-cost bifunctional additive,waxberry-like Fe_(3)O_(4) secondary nanospheres assembled from ultrafine primary Fe_(3)O_(4) nanoparticles,is synthesized,which exhibits significant destabilization and bidirectional catalyzation towards(de)hydrogenation of LiBh_(4).with an optimized addition of 30 wt.% waxberry-like Fe_(3)O_(4),the system initiated dehydrogenation below 100℃ and released a total of 8.1 wt.%h_(2) to 400℃.After 10 cycles,a capacity retention of 70% was achieved,greatly superior to previously reported oxides-modified *** destabilizing and catalyzing mechanisms of waxberry-like Fe_(3)O_(4) on LiBh_(4) were systematically analyzed by phase and microstructural evolutions during dehydrogenation and hydrogenation cycling as well as density functional theory(DFT)*** present work provides new insights in developing advanced nano-additives with unique structural and multifunctional designs towards LiBh4 hydrogen storage.

关键词： LiBh_(4) hydrogen storage waxberry-like Fe_(3)O_(4) Destabilization Catalysis

Fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

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Matter and Radiation at Extremes 2024年第3期9卷 11-18页

作者： Y.X.wang X.L.zhu S.M.weng P.Li X.F.Li h.Ai h.R.Pan Z.M.Sheng Key Laboratory for Laser Plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of Laser Fusion of China Academy of Engineering Physics MianyangSichuan 621900China State key Laboratory of high Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

The generation of ultrashort high-power light sources in the mid-infrared(mid-IR)to terahertz(Thz)range is of interest for applications in a number of fields,from fundamental research to biology and *** conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-IR or Thz ***,we present a photon deceleration scheme for the efficient generation of ultrashort mid-IR or Thz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long *** signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by the driver *** to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index in the plasma wake ***,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer *** greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength IR and Thz spectral ranges.

关键词： laser ultrashort photon

Transient synthesis of carbon-supported high-entropy alloy sulfide nanoparticles via flash Joule heating for efficient electrocatalytic hydrogen evolution

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Nano Research 2024年第4期17卷 3379-3389页

作者： Yuntian Liao Rongtao zhu wenjun Zhang haiyang zhu Yang Sun Jiale Chen Zhenhua Dong Ronghuan Lv School of Chemical Engineering and Technology China University of Mining and TechnologyXuzhou 221116China

high entropy alloys(hEA)are frequently employed as catalysts in electrocatalytic hydrogen ***,the traditional high entropy alloy synthesis methods are time-consuming,energy-intensive,and environmentally polluting,which limits their application in the hydrogen evolution reaction(hER).This study leveraged the capabilities of flash Joule heating(FJh)to synthesize carbon-supported high-entropy alloy sulfide nanoparticles(CC-S-hEA)on carbon cloth(CC)with good self-standing properties within 300 *** carbon thermal shock generated by the Joule heating could pyrolyze the sulfur source into gas,resulting in numerous pore structures and defects on CC,forming an S-doped carbon substrate(CC-S).Then the S atoms were used to stably anchor the metal atoms on CC-S to form high-density uniformly dispersed hEA *** electrochemical test results demonstrated that CC-S-hEA prepared at 60 V flash voltage had hER performance comparable to Pt/*** density functional theory(DFT)calculation indicated that the S atoms on CC-S accelerated the electron transfer between the carbon substrate and hEA ***,the unique electronic structure of CC-S-hEA was beneficial to h*adsorption and promoted catalytic *** simplicity and versatility of FJh synthesis are of great significance for optimizing the synthesis of hEA and improving the quality of hEA products,which provides a broad application prospect for the synthesis of nanocatalysts with efficient hER performance.

关键词： high entropy alloy flash Joule heating carbon thermal shock hydrogen evolution reaction density functional theory

A Note on the Entropy for heisenberg Group Actions on the Torus

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Acta Mathematica Sinica,English Series 2024年第10期40卷 2324-2336页

作者： Yu ZhANG Yu Jun zhu School of Mathematical Sciences Xiamen University

In this paper,the entropy of discrete heisenberg group actions is *** α be a discrete heisenberg group action on a compact metric space *** types of entropies,■ and h(α)are introduced,in which ■ is defined in Ruelle’s way and h(α) is defined via the natural extension of α.It is shown that when X is the torus and α is induced by integer matrices then ■ is zero and h(α) can be expressed via the eigenvalues of the matrices.

关键词： Entropy heisenberg group action natural extension torus

Rationally construction of atomic-precise interfacial charge transfer channel and strong build-in electric field in nanocluster-based Zscheme heterojunctions with enhanced photocatalytic hydrogen production

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Nano Research 2024年第6期17卷 5002-5010页

作者： Qingtao zhu honglei Shen Chao han Liu huang Yanting Zhou Yuanxin Du Xi Kang Manzhou zhu Department of Materials Science and Engineering Centre for Atomic Engineering of Advanced MaterialsKey Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationKey Laboratory of Functional Inorganic Material Chemistry of Anhui ProvinceAnhui UniversityHefei 230601China

The lack of effective charge transfer driving force and channel limits the electron directional migration in nanoclusters(NC)-based heterostructures,resulting in poor photocatalytic ***,a Z-scheme NC-based heterojunction(Pt1Ag28-BTT/CoP,BTT=1,3,5-benzenetrithiol)with strong internal electric field is constructed via interfacial Co-S bond,which exhibits an absolutely superiority in photocatalytic performance with 24.89 mmol·h^(−1)·g−1 h_(2)production rate,25.77%apparent quantum yield at 420 nm,and~100%activity retention in stability,compared with Pt1Ag28-BDT/CoP(BDT=1,3-benzenedithiol),Ag29-BDT/CoP,and *** enhanced catalytic performance is contributed by the dual modulation strategy of inner core and outer shell of NC,wherein,the center Pt single atom doping regulates the band structure of NC to match well with CoP,builds internal electric field,and then drives photogenerated electrons steering;the accurate surface S modification promotes the formation of Co-S atomic-precise interface channel for further high-efficient Z-scheme charge directional *** work opens a new avenue for designing NC-based heterojunction with matchable band structure and valid interfacial charge transfer.

关键词： atomically precise metal nanocluster Z-scheme heterojunction interfacial charge transfer build-in electric field photocatalytic hydrogen production

high-efficiency crystalline white organic lightemitting diodes

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Light(Science & Applications) 2024年第4期13卷 747-759页

作者： Yijun Liu Feng zhu Yue wang Donghang Yan State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China. School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China. State Key Laboratory of Supramolecular Structure and Materials Jilin UniversityChangchun 130012China

Crystalline white organic light-emitting diodes(C-wOLEDs)are promising candidates for lighting and display *** is urgently necessary,however,to develop energy-saving and high-efficiency C-wOLEDs that have stable and powerful emission to meet commercial ***,we report a crystalline host matrix(ChM)with embedded nanoaggregates(NA)structure for developing high-performance C-wOLEDs by employing a thermally activated delayed fluorescence(TADF)material and orange phosphorescent dopants(Phos.-D).The ChM-TADFNA-D wOLED exhibit a remarkable EQE of 12.8%,which is the highest performance wOLEDs based on crystalline *** device has a quick formation of excitons and a well-designed energy transfer process,and possesses a fast ramping of luminance and current *** to recently reported high-performance wOLEDs based on amorphous material route,the C-wOLED achieves a low series-resistance Joule-heat loss ratio and an enhanced photon output,demonstrating its significant potential in developing the next-generation wOLEDs.

关键词： diodes dopant crystalline

Towards a new avenue for rapid synthesis of electrocatalytic electrodes via laser-induced hydrothermal reaction for water splitting

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International Journal of Extreme Manufacturing 2024年第1期6卷 340-351页

作者： Yang Sha Menghui zhu Kun huang Yang Zhang Francis Moissinac Zhizhou Zhang Dongxu Cheng Paul Mativenga zhu Liu Department of Materials School of Natural SciencesThe University of ManchesterOxford RoadManchester M139PLUnited Kingdom Laser Processing Research Centre Department of MechanicalAerospace and Civil EngineeringSchool of EngineeringThe University of ManchesterOxford RoadManchester M139PLUnited Kingdom National Graphene Institute The University of ManchesterOxford RoadManchester M139PLUnited Kingdom Department of Chemical Engineering and Analytical Science School of EngineeringThe University of ManchesterOxford RoadManchester M139PLUnited Kingdom Research Centre for Laser Extreme Manufacturing Ningbo Institute of Materials Engineering and TechnologyChinese Academy of SciencesNingboPeople’s Republic of China

Electrochemical production of hydrogen from water requires the development ofelectrocatalysts that are active,stable,and low-cost for water *** address these challenges,researchers are increasingly exploring binder-free electrocatalytic integratedelectrodes (IEs) as an alternative to conventional powder-based electrode preparation methods,for the former is highly desirable to improve the catalytic activity and long-term stability for large-scale applications of ***,we demonstrate a laser-inducedhydrothermal reaction (LIhR) technique to grow NiMoO4nanosheets on nickel foam,which is then calcined under h2/Ar mixed gases to prepare the IE *** electrode exhibits superior hydrogen evolution reaction performance,requiring overpotentials of 59,116 and143 mV to achieve current densities of 100,500 and 1000 mA·*** the 350 h chronopotentiometry test at current densities of 100 and 500 m A·cm-2,the overpotentialremains essentially *** addition,NiFe-layered double hydroxide grown on Ni foam is also fabricated with the same LIhR method and coupled with IE-NiMo-IR to achieve water *** combination exhibits excellent durability under industrial current *** energy consumption and production efficiency of the LIhR method are systematicallycompared with the conventional hydrothermal *** LIhR method significantly improves the production rate by over 19 times,while consuming only 27.78%of the total energy required by conventional hydrothermal methods to achieve the same production.

关键词： electrocatalytic electrode laser-induced hydrothermal reaction NiFe layered double hydroxides hydrogen evolution reaction water splitting energy consumption production rate

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