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Demixing microwave signals using system-on-chip photonic processor

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Light(Science & Applications) 2024年第3期13卷 399-401页

作者： sheng Gao Chu Wu Xing lin Department of Electronic Engineering Tsinghua University100084 BeijingChina Beijing National Research Center for Information Science and Technology Tsinghua University100084 BeijingChina

The integrated photonic processor,co-packaged with electronic peripherals,is proposed for blind source separation of microwave signals,which separates signal-of-interest from dynamic interference with real-time adapta... 详细信息

关键词： processor microwave mixing

The Simulation of UV-Vis Absorption Spectra and Fluorescence Spectra of Organic Molecules in solvents

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The Simulation of UV-Vis Absorption Spectra and Fluorescence...

The Proton Transfer and Dissociation Dynamics of Water Cluster Ions: H5O2+,D5O2+,and H3D2O2+

中国化学会第十二届全国量子化学会议

作者： Ruihong Duan Chaoyuan Zhu Jianguo Yu sheng hsien lin Department of Applied Chemistry Institute of Molecular Science and Center for Interdisciplinary Molecular ScienceNational Chiao-Tung University Department of Chemistry Beijing Normal University

The UV-Vis absorption and fluorescence spectra of alpha-carboline（AC）and carbazole（CZ）in different solvents,n-hexane and acetonitrile,have been simulated by using Franck-Condon simulation including inhomogeneous broadening of solvent *** harmonic oscillator and scaling factors on the force constant have been applied in the *** equilibrium geometries have been calculated in gas phase and with polarizable continuum model（PCM）in solvent n-hexane and acetonitrile *** DFT method is used to calculate the equilibrium geometries of the ground state S0 for AC and CZ,and the TDDFT method is used to calculate the equilibrium geometries of the first two singlet excited states S1 and *** forces on the solute by solvent can change the restoring force of the atoms in the solute molecule,and we can treat it as constant scaling factors on the force *** simulated spectra by using the geometries in gas phase with scaling factors is much better than that without scaling factors,and the spectra by using the geometries in solvent with scaling factors can match the experiment data almost completely.

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The Proton Transfer and Dissociation Dynamics of Water Clust...

Catalytically generated noncovalent ammonium dienolate:a versatile platform for the development of organocatalytic asymmetric cascade reactions

第十三届全国化学动力学会议

作者： Di Song Hongmei Su Fan-ao Kong sheng-hsien lin Beijing National Laboratory for Molecular Sciences (BNLMS) State Key Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences Institute of Applied Chemistry Institute of Molecular Science Chiao-Tung University

＜正＞Water cluster ions are of great interest since they are involved in aqueous proton transfer which plays important roles in many chemical and biological processes. We investigated the proton transfer and dissocia... 详细信息

关键词： water cluster ions proton transfer dissociation RRKM

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Science China Chemistry 2024年第8期67卷 2524-2546页

作者： Jun-Bing lin Dong-sheng Ji Peng-Fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China Shaanxi Key Laboratory of Chemical Reaction Engineering College of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000China

Organocatalytic cascade reactions represent a powerful strategy for the rapid construction of complex chiral molecules with multiple stereocenters from simple substrates under mild conditions. The intriguing structural feature and diverse reactivity of catalytically generated dienolate species render them competent and versatile intermediates for the development of practical and valuable cascade reactions. Over the past years, a plethora of innovative and pioneering noncovalent ammonium dienolatemediated cascade reactions have been designed and implemented under the catalysis of chiral organocatalysts, making dienolate activation a general, robust, and complementary method for the functionalization of unsaturated carbonyl compounds and related substances. This review illustrates the recent advances in organocatalytic noncovalent ammonium dienolate-mediated cascade reactions(mainly from 2010 to 2023), including the cascade transformations of ammonium dienolates directly generated from unsaturated ketone/aldehyde, ester/lactone/azlactone, amide/lactam/pyrazolone/oxindole, and alkylidene nitrile compounds. The contents are arranged based on the reaction types of the ammonium dienolates, with an emphasis on cascade 2,5-, 3,5-, and 4,5-difunctionalizations of these intermediates. Furthermore, other cascade reactions involving the 1,3-, 2,3-, and even more complex 3,4,5-reactivities of ammonium dienolates were also discussed. The reaction pathway, reaction stereoinduction, and synthetic applications of the ammonium dienolate-mediated cascade reactions were highlighted throughout the article. As a stimulating and ever-growing research area, the organocatalytic noncovalent ammonium dienolate-mediated cascade reactions are expected to continue demonstrating their magic power for constructing chiral targets in the future and further expanding the boundaries of asymmetric catalysis.

关键词： organocatalysis asymmetric catalysis ammonium dienolate cascade reaction difunctionalization

Experimental,Numerical,and Analytical Studies on the Bending of Mechanically lined Pipe

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China Ocean Engineering 2024年第2期38卷 221-232页

作者： WEI Wen-bin YUAN lin ZHOU Jia-sheng LIU Zheng State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China School of Mechanical Engineering Tianjin UniversityTianjin 300072China

Mechanically lined pipe(MLP)is often used for offshore oil and gas transport because of its low cost and corrosion *** installation and operation,the pipe may undergo severe bending deformation,which causes the liner to separate from the outer pipe and buckles,affecting the stability of the whole *** this paper,the buckling response of MLP subjected to bending is investigated to clarify its bending characteristics by employing both experiments,numerical simulation,as theoretical *** types of MLPs were manufactured with GB 45 carbon steel(SLP)and Al 6061(ALP)used as the outer pipe material,*** hydraulic expansion and bending experiments of small-scale MLPs are *** addition to the ovalized shape of the cross-section for the SLP specimens,the copper liner was found to wrinkle on the compressive *** contrast,the liner of ALP remains intact without developing any wrinkling and collapse *** addition,a dedicated numerical framework and theoretical models were also *** was found both the manufacturing and bending responses of the MLP can be well reproduced,and the predicted maximum moment and critical curvatures are in good agreement with the experimental results.

关键词： lined pipe bending nonlinear ring theory buckling plasticity

Restraining growth of Zn dendrites by poly dimethyl diallyl ammonium cations in aqueous electrolytes

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Rare Metals 2024年第8期43卷 3735-3747页

作者： Xiang-Xin Zhang Yuan-Qiang Chen Chang-Xin lin Yuan-sheng lin Guo-lin Hu Yong-Chuan Liu Xi-Lai Xue Su-Jing Chen Zhan-lin Yang Bai-sheng Sa Yi-Ning Zhang Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Helmholtz Institute Ulm(HIU) 89081 UlmGermany Karlsruhe Institute of Technology(KIT) 76021 KarlsruheGermany College of Materials Science and Engineering Fuzhou UniversityFuzhou350108China

Metallic zinc is an excellent anode material for Zn-ion batteries,but the growth of Zn dendrite severely hinders its practical ***,an efficient and economical cationic additive,poly dimethyl diallyl ammonium(PDDA) was reported,used in aqueous Zn-ion batteries electrolyte for stabilizing Zn *** growth of zinc dendrites can be significantly restrained by benefiting from the pronounced electrostatic shielding effect from PDDA on the Zn metal ***,the PDDA is preferentially absorbed on Zn(002) plane,thus preventing unwanted side reactions on Zn *** to the introduction of a certain amount of PDDA additive into the common ZnSO_(4)-based electrolyte,the cycle life of assembled Zn‖Zn cells(1 mA·cm^(-2) and 1 mAh·cm^(-2)) is prolonged to more than 1100 *** response to the perforation issue of Zn electrodes caused by PDDA additives,the problem can be solved by combining foamy copper with zinc *** real application,Zn-ion hybrid supercapacitors and MnO_(2)‖Zn cells were assembled,which exhibited excellent cycling stability with PDDA *** work provides a new solution and perspective to cope with the dendrite growth problem of Zn anode.

关键词： PDDA Electrostatic shielding effect Zn anode Zn dendrites

Effect of Mo and cold forging deformation on strength and ductility of cobalt-based alloy L605

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Journal of Iron and Steel Research International 2024年第7期31卷 1811-1823页

作者： Zhong-lin Wang Zhi-hua Gong Quan Li Han-sheng Bao School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014017Inner MongoliaChina Institute of Special Steels Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China

Mo element was added to cobalt-based alloy L605,and cold forging deformation was *** effects of the addition and cold forging deformation on the microstructure and mechanical properties of the alloy were studied by thermodynamic calculation,electron backscatter diffraction,transmission electron microscopy,and X-ray *** stacking fault energy(SFE)of the alloy decreased after the addition,and the formation of stacking faults and intersections were promoted to improve the strength and *** tensile strength of the alloy with Mo increased from 1190 to 1702 MPa after 24%cold deformation,producing significant work *** strengthening mechanism is strain-induced martensitic transformation(SIMT)and deformation *** alloy,combined with Mo and after 24%deformation,had both high strength and ductility in comparison with the original cobalt-based alloy *** is attributed to the lower SFE which caused the increase in stacking fault *** the tensile process,theε-hcp phase was easily generated at the stacking fault to reduce the stress concentration and increase the *** SIMT by adjusting the density of stacking faults can improve the mechanical properties of cobalt-based ***ε-hcp phase,the interaction between deformation twins and dislocations,and the interaction between e-hcp phases during cold forging deformation caused local stress concentration,lowering ductility and toughness.

关键词： Cobalt-based alloy-Stacking fault energy Strain-induced martensitic transformation Deformation twin Cold forging deformation

Engineering Ru（N^N）3-modified covalent organic framework for photocatalytic olefin epoxidation

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Science China Chemistry 2024年第11期67卷 3719-3728页

作者： Yan-lin Li sheng-Li Huang Guo-Yu Yang Key Laboratory of Cluster Science (Ministry of Education) Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical Engineering Beijing Institute of Technology

Photocatalytic olefin oxidation using air as an oxidant is an environmentally friendly method for producing epoxides. Covalent organic frameworks（COFs） have emerged as promising photocatalysts in various organic synthesis reactions. The combination of tri-（2-pyridinal aldehyde）-containing precursor with 4,4’,4’’-（1,3,5-triazine-2,4,6-triyl）trianiline generated（N^N）-I-COF. Via imine-to-quinoline transformation and coordination anchorage of Ru（N^N）3unit, Ru（N^N）3@Q-COF was obtained with improved chemical stability, skeleton conjugation, and novel photochemical characteristics, and demonstrated excellent photocatalytic activity in olefin epoxidation with a wide range of substrates. The presence of H2O played a crucial role in the formation of reactive oxygen species（ROSs）, which in turn influenced the olefin oxidation process. The hydrophilicity of Ru（N^N）3facilitated the approach of H2O and O2to the photogenerated charges, thereby promoting ROSs generation. The lipophilicity of Q-COF allowed for the absorption of olefin substrates, and its nano-channels increased encountering possibility between olefins and ROSs. Consequently, Ru（N^N）3@Q-COF provided an intriguing platform for olefin photooxidation and could be recycled multiple times without any degradation in performance. This report revealed that the conversion of classical ROSs into less potent oxidants with rapid kinetic rates played a crucial role in achieving highly efficient and selective epoxidation of terminal olefins.

关键词： polypyridyl Ru covalent organic framework olefin epoxidation photocatalysis

Imide-pillared covalent organic framework protective films as stable zinc ion-conducting interphases for dendrite-free Zn metal anodes

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Journal of Energy Chemistry 2024年第10期97卷 470-477,I0010页

作者： Xiaoman Ye Xuemei Xiao Zhijing Wu Xin Wu lin Gu sheng Liu School of Chemical Engineering and Technology Sun Yat-sen UniversityZhuhai 519082GuangdongChina The Key Lab of Low-Carbon Chemistry&Energy Conservation of Guangdong Province Sun Yat-sen UniversityGuangzhou 510275GuangdongChina

The notorious growth of zinc dendrite and the water-induced corrosion of zinc metal anodes(ZMAs)restrict the practical development of aqueous zinc ion batteries(AZIBs).In this work,a zinc metallized,imide-pillared covalent organic framework(ZPC)protective film has been engineered as a stable Zn^(2+)ion-conducting interphase to modulate interfacial kinetics and suppress side reactions for *** to bare Zn,ZPC@Zn exhibits a higher Zn^(2+)ionic conductivity,a larger Zn^(2+)transference number,a lower electronic conductivity,a smaller desolvation activation energy and correspondingly a significant suppression of corrosion,hydrogen evolution and Zn ***,the ZPC@Zn||ZPC@Zn symmetric cell obtains a cycling lifespan over 3000 h under 5 mA cm^(-2)for 1 mA h cm^(-2).The ZPC@Zn||NH_(4)V_(4)O_(10)coin-type full battery delivers a specific capacity of 195.8 mA h g^(-1)with a retention rate of78.5%at 2 A g^(-1)after 1100 cycles,and the ZPC@Zn||NH_(4)V_(4)O_(10) pouch full cell shows a retention of70.1%in reversible capacity at 3 A g^(-1)after 1100 *** present incorporation of imide-linked covalent organic frameworks in the surface modification of ZMAs will offer fresh perspectives in the search for ideal protective films for the practicality of AZIBs.

关键词： Aqueous zinc ion batteries Zinc metal anodes Surface modification Covalent organic frameworks Imide linkage