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Modular Synthesis of Multi-substituted Cyclobutanones Enabled by Oxyallyl Cations

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Chinese Journal of Chemistry 2024年第5期42卷 459-463页

作者： meng wang Zhonggui wang Ping Lu Research Center for Molecular Recognition and Synthesis Department of ChemistryFudan University220 Handan LuShanghai200433 China Present address: Department of Cancer Biology Dana-Farber Cancer Institute Department of Biological Chemistry and Molecular Pharmacology Harvard Medical SchoolBostonMA 02115USA

Stereoselective synthesis of multi-substituted cyclobutanes with different substituents is still a daunting challenge in organic *** report here a practical and facile approach to synthesizing all-trans 2,3,4-trisubstituted cyclobutanones from readily available *** substitution reaction proceeds smoothly via oxyallyl cation intermediates under mild basic *** transformation to the synthesis of 1,2,3,4-tetrasubstituted cyclobutanes was also explored.

关键词： Diastereoselectivity Modular synthesis Nucleophilic substitution Organohalides Oxyallyl cation Precision functionalization Strained molecules 1,2,3,4-Tetrasubstituted cyclobutanes

Single transmembrane GPCR modulating proteins:neither single nor simple

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Protein & Cell 2024年第6期15卷 395-402页

作者： meng wang Jianjun Lyu Chao Zhang Department of Plastic and Reconstructive Surgery Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China Hubei Topgene Research Institute of Hubei Topgene Biotechnology Co. LtdEast Lake High-Tech Development ZoneWuhan 430205China Fundamental Research Center Shanghai Yangzhi Rehabilitation Hospital (Shanghai Sunshine Rehabilitation Center)Tongji UniversityShanghai 200092China

The discovery of G-protein coupled receptor(GPCR)accessory proteins has fundamentally redefined the pharmacological concept of GPCR signaling,demonstrating a more complex molecular basis for receptor specificity on the plasma membrane and impressionable downstream intracellular *** accessory proteins not only contribute to the proper folding and trafficking of receptors but also exhibit selectable receptor preferences.

关键词： specificity GPCR neither

Reachability-Based Confidence-Aware Probabilistic Collision Detection in Highway Driving

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Engineering 2024年第2期33卷 90-107页

作者： Xinwei wang Zirui Li Javier Alonso-Mora meng wang School of Engineering and Materials Science Queen Mary University of LondonLondon E14NSUK Department of Cognitive Robotics Delft University of TechnologyDelft 2628 CDNetherlands School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Chair of Traffic Process Automation “Friedrich List”Faculty of Transport and Traffic SciencesTU DresdenDresden 01069Germany

Risk assessment is a crucial component of collision warning and avoidance systems for intelligent ***-based formal approaches have been developed to ensure driving safety to accurately detect potential vehicle ***,they suffer from over-conservatism,potentially resulting in false–positive risk events in complicated real-world *** this paper,we combine two reachability analysis techniques,a backward reachable set(BRS)and a stochastic forward reachable set(FRS),and propose an integrated probabilistic collision–detection framework for highway *** this framework,we can first use a BRS to formally check whether a two-vehicle interaction is safe;otherwise,a prediction-based stochastic FRS is employed to estimate the collision probability at each future time ***,the framework can not only identify non-risky events with guaranteed safety but also provide accurate collision risk estimation in safety-critical *** construct the stochastic FRS,we develop a neural network-based acceleration model for surrounding vehicles and further incorporate a confidence-aware dynamic belief to improve the prediction *** experiments were conducted to validate the performance of the acceleration prediction model based on naturalistic highway driving *** efficiency and effectiveness of the framework with infused confidence beliefs were tested in both naturalistic and simulated highway *** proposed risk assessment framework is promising for real-world applications.

关键词： Probabilistic collision detection Confidence awareness Probabilistic acceleration prediction Reachability analysis Risk assessment

Enhanced potassium storage of carbon nanofibers as binderfree anodes enabled by coupling ultra-small amorphous Sb_(2)O_(3),graphene modification and sulfur doping

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Rare Metals 2024年第1期43卷 51-64页

作者： Zhao Huang Yu-Kang Lou Lin Peng Yuan Peng meng-meng wang Ming Zhang College of Railway Transportation Hunan University of TechnologyZhuzhou 412007China College of Semiconductors(College of Integrated Circuits) Changsha Semiconductor Technology and Application Innovation Research InstituteHunan UniversityChangsha 410082China Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education College of Semiconductors(College of Integrated Circuits)Hunan UniversityChangsha 410082China

Considering the intrinsic advantages of natural copiousness and cost-effectiveness of potassium resource,potassium-ion batteries(KIBs) are booming as prospective alternatives to lithium-ion batteries(LIBs) in large-scale energy storage scenarios. Nevertheless, lacking desirable electrodes for reversibly hosting the bulky K+hinders the widespread application of KIBs, and it needs to be urgently solved. Hereon, the porous S-doped Sb_(2)O_(3)-graphene-carbon(SAGC) nanofibers are manufactured through an adjustable and facile approach, which involves electrospinning, in situ etching and sulfuration. The synthesized SAGC is featured by the ultra-small amorphous Sb_(2)O_(3) homogeneously wrapped inside the carbon matrix, as well as the co-incorporation of graphene and sulfur. Tentatively,the SAGC nanofiber sheets are applied as binder-free anodes for KIBs, exhibiting a prominent cycling life(256.72 m Ah·g^(-1) over 150 cycles at 100 m A·g^(-1)) and rate·g^(-1) over 100 cycles at 1 A·g^(-1)). The positive synergy among all the active components accounts for the distinguished performances of the SAGC. By reinforcing the tolerability to the swelling stress, producing the valid electrochemical active sites, and promoting the charge transferring for reversible K+uptake, the SAGC finally renders the excellent cyclability, capacity, and rate capability. Moreover, the extrinsic electrochemical pseudocapacitance characteristics induced by the porous carbon substrate elevate the K-storage capacity of the SAGC as well. It is hoped that the conclusions drawn may offer new insights into a direction for the high-performance binderfree KIB anodes.

关键词： S-doped Sb_(2)O_(3)-graphene-carbon Nanofibers Binder-free Anodes Potassium-ion batteries

Synthesis,structure,and luminescence properties of melilite Dy^(3+):Lu_(x)CaLa_(0.98-x)Ga_(3)O_(7) phosphors for use in yellow light-emitting devices

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Journal of Rare Earths 2024年第8期42卷 1489-1495,I0003页

作者： Yunyun Liu Chuanxin Huang meng wang Xihu wang Yan wang Ju Gao School of Opto-Electronic Engineering Zaozhuang UniversityZaozhuang277160China Key Laboratory of Functional Materials and Devices for Informatics of Anhui Educational Institutions Department of PhysicsFuyang Normal UniversityFuyang236037China Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002.China

Dy^(3+) and Lu^(3+) co-doped CaLaGa_(3)O_(7) phosphors were prepared via high-temperature solid-phase *** electronic structures of LuxCaLa_(0.98-x)Ga_(3)O_(7) were investigated by the first-principles *** influence of Lu^(3+) on yellow light emission was studied using X-ray diffraction(XRD)and photoluminescence(PL) *** XRD results indicate that compared to Dy^(3+):CaLaGa_(3)O_(7),the cell parameters of Dy^(3+):LuCaLaGa_(3)O_(7) tend to decrease,which is due to the smaller radius of Lu^(3+).When pumped by blue GaN laser diode(LD),the emission peaks of phosphors with different Lu^(3+)doping concentrations in the visible region are similar,with the strongest peak at 574 nm in the yellow light region,which is sensitive to human *** optimal doping concentration of Lu^(3+) is confirmed to be1 at%,when all emission spectra and measured fluorescence lifetimes are taken into ***,the optimal phosphor composition Dy^(3+):Lu_(x)CaLa_(0.98-x)Ga_(3)O_(7)(x=0.01) has an internal quantum efficiency(IQE) of 46.94% and an external quantum efficiency(EQE) of 15.19%.Most notably,the prepared phosphor demonstrates excellent thermal stability and a high activation energy(0.203 eV).In addition,the International Illumination Commission color coordinates of the Dy^(3+):LuxCaLa_(0.98-x)Ga_(3)O_(7) phosphors are in the yellow light *** above analysis indicates that the Dy^(3+):LuxCaLa_(0.98-x)Ga_(3)O_(7)(x=0.001)phosphor has promising application prospects in yellow light-emitting devices.

关键词： Dy^(3+):Lu_(x)CaLa_(0.98-x)Ga_(3)O_(7)phosphors Yellow emission Structure characteristics Luminescent properties Rare earths

Characterization of a smog chamber for studying formation of gas-phase products and secondary organic aerosol

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Journal of Environmental Sciences 2024年第2期136卷 570-582页

作者： Qi Yuan Zhuozhi Zhang meng wang Kin Fai Ho Tao wang Shuncheng Lee Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina School of Public Health and Primary Care The Chinese University of Hong KongShatinHong KongChina

Smog chambers provide a potent approach to explore the secondary organic aerosol formation under varied *** study describes the construction and characterization of a new smog chamber facility for studying the formation mechanisms of gas-phase products and secondary organic aerosol from the photooxidation of volatile organic *** chamber is a 5.4 m^(3) Fluorinated Ethylene Propylene(FEP)Teflon reactor with the potential to perform photooxidation experiments at controlled temperature and relative *** characterizations were conducted for evaluation of stability of environmental parameters,mixing time,background contamination,light intensity,and wall losses of gases and *** photolysis rate of NO_(2)(J_(NO2))ranged from(1.02-3.32)×10^(-3)sec^(-1),comparable to the average J_(NO2)in ambient *** wall loss rates for NO,NO_(2),and O_(3)were 0.47×10^(-4),0.37×10^(-4),and 1.17×10^(-4)min^(-1),while wall loss of toluene was obsoletely found in a 6 hr *** particle number wall loss rates are(0.01-2.46)×10^(-3)min^(-1)for 40-350 nm with an average lifetime of more than one day.A series of toluene photooxidation experiments were carried out in absence of NO_xunder dry *** results of the simulation experiments demonstrated that the chamber is well designed to simulate photolysis progress in the atmosphere.

关键词： Smog chamber Gas-phase oxidation Chamber characterization Chemical mechanism

A three-dimensional co-continuous network structure polymer electrolyte with efficient ion transport channels enabling ultralong-life all solid-state lithium metal batteries

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Journal of Energy Chemistry 2024年第7期94卷 635-645页

作者： meng wang Hu Zhang Yewen Li Ruiping Liu Huai Yang School of Chemical&Environmental Engineering China University of Mining and Technology(Beijing)Beijing 100083China Beijing Advanced Innovation Center for Materials Genome Engineering&School of Materials Science and Engineering Peking UniversityBeijing 100871China

Solid polymer electrolytes(SPEs)have emerged as one of the most promising candidates for the construction of solid-state lithium batteries due to their excellent flexibility,scalability,and interface compatibility with ***,a novel all-solid polymer electrolyte(PPLCE)was fabricated by the copolymer network of liquid crystalline monomers and poly(ethylene glycol)dimethacrylate(PEGDMA)acts as a structural frame,combined with poly(ethylene glycol)diglycidyl ether short chain interspersed serving as mobile ion transport *** preparaed PPLCEs exhibit excellent mechanical property and out-standing electrochemical performances,which is attributed to their unique three-dimensional cocontinuous structure,characterized by a cross-linked semi-interpenetrating network and an ionic liquid phase,resulting in a distinctive nanostructure with short-range order and long-range ***,the addition of PEGDMA is proved to be critical to the comprehensive performance of the PPLCEs,which effectively modulates the microscopic morphology of polymer networks and improves the mechanical properties as well as cycling stability of the solid *** used in a lithiumion symmetrical battery configuration,the 6 wt%-PPLCE exhibites super stability,sustaining operation for over 2000 h at 30 C,with minimal and consistent overpotential of 50 *** resulting Li|PPLCE|LFP solid-state battery demonstrates high discharge specific capacities of 160.9 and 120.1 mA h g^(-1)at current densities of 0.2 and 1 C,*** after more than 300 cycles at a current density of 0.2 C,it retaines an impressive 73.5%***,it displayes stable cycling for over 180 cycles at a high current density of *** super cycle stability may promote the application for ultralong-life all solid-state lithium metal batteries.

关键词： Solid-state electrolyte Lithium-metal batteries Liquid crystalline polymer Copolymer 3D co-continuous structure Long cycle stability

Superexchange and charge transfer in the nickelate superconductor La3Ni2O7 under pressure

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Science China(Physics,Mechanics & Astronomy) 2024年第11期Mechanics & Astronomy) .卷 5-12页

作者： Wéi Wú Zhihui Luo Dao-Xin Yao meng wang Center for Neutron Science and Technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and DevicesSchool of Physics Sun Yat-sen University

Recently, a bulk nickelate superconductor La3Ni2O7is discovered at pressures with a remarkable high transition temperature Tc～ 80 K. Here, we study a Hubbard model with tight-binding parameters derived from ab initio calculations of La3Ni2O7,by employing large scale determinant quantum Monte Carlo and cellular dynamical mean-field theory. Our result suggests that the superexchange couplings in this system are comparable to that of cuprates. The system is a charge transfer insulator as the hole concentration becomes four per site at large Hubbard U. Upon hole doping, two low-energy spin-singlet bands emerge in the system exhibiting distinct correlation properties: while the one composed of the out-of-plane Ni-d3z2-r2and O-pzorbitals demonstrates strong antiferromagnetic correlations and narrow effective bandwidth, the in-plane singlet band consisting of the Ni-dx2-y2and O-px/pyorbitals is in general more itinerant. Over a broad range of hole doping, the doped holes occupy primarily the dx2-y2and px/pyorbitals, whereas the d3z2-r2and pzorbitals retain underdoped. We propose an effective t-J model to capture the relevant physics and discuss the implications of our result for comprehending the La3Ni2O7superconductivity.

关键词： superconductivity nickelate superconductors Hubbard model superexchange charge transfer insulator quantum Monte Carlo

Parameter calibration of the tensile-shear interactive damage constitutive model for sandstone failure

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1153-1174页

作者： Yun Shu Zheming Zhu meng wang Weiting Gao Fei wang Duanying Wan Yuntao wang MOE Key Laboratory of Deep Earth Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu610065China Failure Mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan ProvinceSichuan UniversityChengdu610065China Tianfu Engineering-oriented Numerical Simulation & Software Innovation Center Chengdu620107China

The tensile-shear interactive damage(TSID)model is a novel and powerful constitutive model for rock-like *** study proposes a methodology to calibrate the TSID model parameters to simulate *** basic parameters of sandstone are determined through a series of static and dynamic tests,including uniaxial compression,Brazilian disc,triaxial compression under varying confining pressures,hydrostatic compression,and dynamic compression and tensile tests with a split Hopkinson pressure *** on the sandstone test results from this study and previous research,a step-by-step procedure for parameter calibration is outlined,which accounts for the categories of the strength surface,equation of state(EOS),strain rate effect,and *** calibrated parameters are verified through numerical tests that correspond to the experimental loading *** between numerical results and experimental data indicates the precision and reliability of the calibrated *** methodology presented in this study is scientifically sound,straightforward,and essential for improving the TSID ***,it has the potential to contribute to other rock constitutive models,particularly new user-defined models.

关键词： Damage constitutive model Parameter calibration Rock modeling Sandstone Dynamic impact load Tensile-shear interactive damage(TSID)model