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Extension of Highly Efficient Alcohol-promoted Rearrangement into One-pot Domino Palladium-catalyzed Carbonylation for Sterically Crowded Aromatic Six-membered Imides

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Chemical Research in Chinese Universities 2023年第6期39卷 1106-1110页

作者： GUO Rong ZHANG Jingmei JIA Xiaohui SHI Chunfeng qie Fengxiang ZHEN Yonggang Advanced Innovation Center for Soft Matter Science and Engineering State Key Laboratory of Organic-Inorganic CompositesBeijing University of Chemical TechnologyBeijing 100029P.R.China State Key Laboratory of Catalytic Materials and Reaction Engineering Research Institute of Petroleum ProcessingSINOPECBeijing 100083P.R.China national Demonstration Center for Experimental Life Sciences&Biotechnology Education Beijing Normal University100875 BeijingP.R.China Wuhan national Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074P.R.China State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen UniversityGuangzhou 510275P.R.China State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024P.R.China

Aromatic six-membered imides suffer the introduction of bulky substituents at the imide positions due to the formation of isoimides and low reactivity,preventing from the investigation of the intrinsic molecular ***,we found a highly efficient alcohol-promoted rearrangement from isonaphthalimide to naphthalimide under acid or basic nonaqueous conditions,which can be regarded as model compounds for aromatic six-membered *** proposed two-step nucleophilic substitutions in the isomerization mechanistic pathways that were verified by the separation of a key ***,in-situ ^(1)H NMR exhibited the first-order kinetics for the isoimide loss ***,the alcohol-promoted isoimide-imide rearrangement was extended to a palladium-catalyzed one-pot domino carbonylation reaction toward sterically crowded aromatic six-membered imides.

关键词： Bulky aromatic imide Imide isomerization Domino synthesis Organic semiconductor

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Elevated degradation of di-n-butyl phthalate by activating peroxymonosulfate over GO-CoFe_(2)O_(4)composites:Synergistic effects and mechanisms

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Chinese Chemical Letters 2023年第12期34卷 310-317页

作者： Qingliang Liu Hang qie Zhiqiang Sun Yufei Zhen Liying Wu Ying Zhao Jun Ma State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology.Harbin 150090China

Rational design of heterogeneous catalysts with high activity and stability is crucial in peroxymonosulfate(PMS)-based oxidation treatment of ***,the graphite oxide-cobalt ferrite(GOCoFe_(2)O_(4))composite was constructed,and its morphological,component and structural characteristics were thoroughly examined,***-CoFe_(2)O_(4)obviously boosted PMS catalytic performance on di-n-butyl phthalate removal(DBP,RpBp=90%,Roc=37%),which indicated by the first-order kinetic constant(kpBp=0.060 min^(-1))being roughly 4 times than pure CoFe_(2)O_(4)(kpBp=0.015 min-1).The fabrication of GO-CoFe_(2)O_(4)brought the favorable stability and repeatability up to six ***,the method of batch dosing catalyst was creatively proposed to improve the PMS utilization *** coupling of GO enhanced the dispersion of CoFe_(2)O_(4)particles to obtain sufficient active sites,additionally,the plentiful C=O groups and free-flowing electrons on GO promoted GO-CoFe_(2)O_(4)to coordinate a redox process during PMS *** the aid of theoretical calculations,GO-CoFe_(2)O_(4)was revealed to exhibit a strong affinity toward PMS adsorption,where PMS spontaneously dissociated into sulfate radical(SO_(4)^(·-)),hydroxyl radical(^(·)OH)and singlet oxygen(^(1)O_(2)),acting as the reactive oxygen species(ROSs).Electrons cycling between Co,Fe and O species ensured continuous ROSs generation and excellent catalytic performance.

关键词： Peroxymonosulfate Cobalt ferrite Graphene oxide Synergistic effect Di-n-butyl phthalate

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Characteristics of a Negative Cloud-to-Ground Lightning Discharge Based on Locations of VHF Radiation Sources

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Atmospheric and Oceanic Science Letters 2014年第3期7卷 248-253页

作者： SUN Zhu-Ling qie Xiu-Shu LIU Ming-Yuan Key Laboratory of Middle Atmosphere and Global Environment Observation (LAGEO) Institute of Atmospheric PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences

The lightning very high frequency （VHF） radiation location system based on the short-baseline time-difference of arrival （TDOA） technique provides an effective approach to describe the temporal and spatial development of lightning discharge in two dimensions with high resolution. A negative single-stroke cloud-to- ground （CG） lightning flash was analyzed in detail using the radiation location results and synchronic fast/slow elec- tric field changes. The long-duration preliminary break- down process appeared to propagate with hi-directional leader channels. The two negative simultaneous discharge channels sloped down with a considerable horizontal com- ponent in the lower positive charge region at speeds of about 105 m s-1. The stepped leader was clearly converted from one channel of the preliminary breakdown process and spread downwards with branches. The speeds of the stepped leaders were about 105 m s -1. The K processes after the return stroke could either directly initiate from the start region with negative polarity lightning discharge, or initiate from a new region in the cloud as negative recoil streamers. All K processes propagated along the preceding electrified channel, while not all K processes initiated from the tips of positive breakdowns. The speeds of the K processes were about 106-107 m s-1.

关键词： short-baselinevery high frequency radiation cloud-to-ground lightningdischarge

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Tuning porosity of coal-derived activated carbons for CO_(2) adsorption

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Frontiers of Chemical Science and Engineering 2022年第9期16卷 1345-1354页

作者： Zhipeng qie Lijie Wang Fei Sun Huan Xiang Hua Wang Jihui Gao Guangbo Zhao Xiaolei Fan School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Department of Chemical Engineering and Analytical Science The University of ManchesterManchester M139PLUK China Datang Corporation Renewable Energy Science and Technology Research Institute Beijing 100052China Energy and Bioproducts Research Institute(EBRI) Aston UniversityBirmingham B47ETUK

A simple method was developed to tune the porosity of coal-derived activated carbons,which provided a model adsorbent system to investigate the volumetric CO_(2)adsorption ***,the method involved the variation of the activation temperature in a K2CO3 induced chemical activation process which could yield activated carbons with defined microporous(nalysis and molecular dynamics simulation demonstrated that(i)volumetric CO_(2)adsorption capacity is directly proportional to the ultra-micropore volume,and(ii)an increase in micropore sizes is beneficial to improve the volumetric capacity,but may lead a low CO_(2)adsorption density and thus low pore space utilization *** adsorption experiments on the activated carbons established the criterion for designing CO_(2)adsorbents with high volumetric adsorption capacity.

关键词： coal-derived activated carbons porosity CO_(2)adsorption molecular dynamics

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Tunable terahertz acoustic-phonon emission from monolayer molybdenum disulfide

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Chinese Physics B 2022年第12期31卷 470-475页

作者： Cheng-Xiang Zhao Miao-Miao Zheng Yuan qie Fang-Wei Han College of Physics and Information Engineering Shanxi Normal UniversityTaiyuan 030031China School of Medical Information Engineering Jining Medical UniversityJining 272067China

The acoustic-phonon emission from monolayer molybdenum disulfide(ML-MoS_(2))driven by a direct-current electric field is studied theoretically using the Boltzmann equation *** is found that the Cerenkov emission of terahertz acoustic-phonons can be generated when a very weak electric field is applied to ML-MoS_(2).The physical mechanisms of acoustic-phonon emission are analyzed from the perspective of condensed matter *** acoustic-phonon emission from ML-MoS_(2)is also compared with those from graphene and *** results reveal that the frequencies of acousticphonons generated by ML-MoS_(2)are between the frequencies of those generated from GaAs and *** results of this work suggest that the ML-MoS_(2)can make up for graphene and GaAs in respect of acoustic-phonon emission and be used in tunable hypersonic devices such as terahertz sound sources.

关键词： acoustic-phonon emission terahertz monolayer molybdenum disulfide

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Numerical simulation of flow and heat transfer of continous cast steel slab under traveling magnetic field

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China Foundry 2013年第2期10卷 92-98页

作者： Gong Haijun Li Xinzhong Fan Xueyi qie Juhong Xu Daming Guo Jingjie School of Materials Science and Engineering Harbin Institute of Technology

A unified numerical model for simulating solidification transport phenomena (STP) of steel slab in electromagnetic continuous casting (EMCC) process was developed. In order to solve the multi-physics fields coupled problem conveniently, the complicated bidirectional coupled process between EM and STP was simplified as a unidirectional one, and a FEM/FVM-combined numerical simulation technique was adopted. The traveling magnetic fields (TMFs) applied to the EMCC process were calculated using the ANSYS11.0 software, and then the EM-data output by ANSYS were converted to FVM-format using a data-format conversion program developed previously. Thereafter, the governing equations were solved using a pressure-based Direct-SIMPLE algorithm. The simulation results of the STP in CC-process show that, due to the influences of Lorentz force and Joule heat, the two strong circulating flows and the temperature field can be obviously damped and changed once TMF with one pair of poles (1-POPs) or 2-POPs is applied, which would accordingly improve the quality of casting. It was found in the present research that the integrated actions of 2-POPs TMF are superior to 1-POPs. All the computations indicate that the present numerical model of EM-STP as well as the FEM/FVM-combined technique is successful.

关键词： continuous casting flow field electromagnetic field ANSYS Direct-SIMPLE algorithm FEM/FVM

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Gradient layered MXene/Fe_(3)O_(4)@CNTs/TOCNF ultrathin nanocomposite paper exhibiting effective electromagnetic shielding and multifunctionality

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nano Research 2024年第9期17卷 8233-8242页

作者： Zhengkun Ma Jingzong He Shilin Liu Xiaoxuan qie Meiheng Gan Ruonan Cheng Qilin Wu Malcolm Xing State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China College of Chemistry and Chemical Engineering Donghua UniversityShanghai 201620China Department of Mechanical Engineering University of ManitobaWinnipegMB R3T 2N2Canada

As wearable electronic devices are rapidly developing,there is an urgent need for lightweight,flexible,and ultrathin multifunctional electromagnetic interference(EMI)shielding ***,the flexible ultrathin paper that combines efficient shielding and multifunctional integration remains a considerable ***,a novel MXene/Fe_(3)O_(4)@CNTs/TOCNF(MCT,MXene=transition metal carbide/carbonitride,CNTs=carbon nanotubes,TOCNF=TEMPO-oxidized cellulose nanofiber,TEMPO=2,2,6,6-tetramethylpiperidine-1-oxyl radical)nanocomposite paper with a multilayer electromagnetic gradient structure and electromagnetic dual losses was successfully prepared by a simple filtration *** from effective gradient design and adjusting the proportion of TOCNF,the composite paper(only 18μm)exhibits outstanding shielding effectiveness(SE)of 66 dB in the X-band,ultrahigh thickness-specific SE and surface-specific SE values of 3300 dB·mm-1 and 31,428 dB·cm^(2)·g^(-1)***,dehydroxylation treatment improves MCT paper's hydrophobicity,environmental stability,and mechanical strength,expanding its range of ***,the highly efficient Joule heating properties and hydrophobicity provide MCT additional de-icing *** also simulated the electromagnetic shielding effects of MCT composite paper,which was applied in *** study documents an innovative and intriguing material combination,providing a simple and effective manufacturing strategy for developing EMI shielding *** paper is highly suitable for outdoor portable or wearable electronic devices and has significant application potential in humid/severe cold environments.

关键词： cellulose fiber thin papers nanocomposites electromagnetic interference(EMI)shielding

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Microbially Induced Carbonate Precipitation in a Middle Triassic Microbial Mat Deposit from Southwestern China:New Implications for the Formational Process of Micrite

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Journal of Earth Science 2021年第3期32卷 633-645页

作者： Mao Luo Jitao Chen Wenkun qie Jinyuan Huang Qiyue Zhang Changyong Zhou Wen Wen State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PalaeoenvironmentChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China Institute of Geological Survey China University of GeosciencesWuhan 430074China Chengdu Center of China Geological Survey Chengdu 610081China

Lime mud(i.e.,micrite)is a major component of carbonate *** mechanisms(biotic versus abiotic)have been proposed for the formation of lime mud in Earth’s ***,the detailed role that microbes play in the nucleation and subsequent precipitation of micrites remains to be *** we undertook a detailed geobiological characterization of laminated lime mudstone from the Middle Triassic Guanling Formation in Yunnan Province,southwestern *** features,together with previous geobiological investigations,suggest that the laminated lime mudstones represent the former presence of microbial *** lime mudstones consist mainly of calcite,dolomite and quartz,with clay minerals and pyrites as subordinate *** particular,micro-analysis shows copious nano-globules(65–878 nm)and capsule-shaped nano-rods in *** low-Mg calcite nano-globule aggregates are closely associated with mucilaginous biofilms resembling extracellular polymeric substances(EPS).nano-sized globules coalesce to form semi-euhedral micrite *** suggest that a decaying hydrolytic destruction of the EPS by microbial communities within microbial mat leads to the precipitation of the nano-globules by enhancing alkalinity in local *** an intermediate,these nano-globules further aggregate to form micrite crystals possibly through a dissolution-reprecipitation process.

关键词： nano-globule EPS micrite microbial mat Middle Triassic Luoping Biota

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A path planning algorithm for autonomous ﬂying vehicles in cross-countryenvironments with a novel TF-RRT^(*) method

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Green Energy and Intelligent Transportation 2022年第3期1卷 81-93页

作者： Tianqi qie Weida Wang Chao yang Ying Li Wenjie Liu Changle Xiang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China Chongqing Innovation Center Beijing Institute of TechnologyChongqing401120China

Autonomous flying vehicles(AFVs)are promising future vehicles,which have high obstacle avoidance *** plan a feasible path in a wide range of cross-country environments for the AFV,a triggered forward optimal rapidly-exploring random tree(TF-RRT^(*))method is ***,an improved sampling and tree growth mechanism is *** and tree growth are allowed only in the forward region close to the target point,which significantly improves the planning speed;Secondly,the driving modes(ground-driving mode or air-driving mode)of the AFV are added to the sampling process as a planned state for uniform planning the driving path and driving mode;Thirdly,according to the dynamics and energy consumption models of the AFV,comprehensive indicators with energy consumption and efficiency are established for path optimal procedures,so as to select driving mode and plan driving path reasonably according to the *** proposed method is verified by simulations with an actual cross-country *** show that the computation time is decreased by 71.08%compared with Informed-RRT^(*)algorithm,and the path length of the proposed method decreased by 13.01%compared with RRT^(*)-Connect algorithm.

关键词： Autonomous flying vehicles(AFVs) Path planning Rapidly-exploring random tree(RRT) Mode switch

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Design of Lattice Structures Using Local Relative Density Mapping Method

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Chinese Journal of Mechanical Engineering 2018年第5期31卷 110-118页

作者： Guo-Hua Song Shi-Kai Jing Fang-Lei Zhao Ye-Dong Wang Hao Xing Long-Fei qie Beijing Xinghang Mechanical-electrical Equipment Co.Ltd. Beijing 100074 China School of Mechanical Engineering Beijing Institute of Technology Beijing 100081 China

In order to solve the problem of substantial computational resources of lattice structure during optimization, a local relative density mapping(LRDM) method is proposed. The proposed method uses solid isotropic microstructures with penalization to optimize a model at the macroscopic scale. The local relative density information is obtained from the topology optimization result. The contour lines of an optimized model are extracted using a density contour approach, and the triangular mesh is generated using a mesh generator. A local mapping relationship between the elements’ relative density and the struts’ relative cross?sectional area is established to automatically determine the diameter of each individual strut in the lattice structures. The proposed LRDM method can be applied to local finite element meshes and local density elements, but it is also suitable for global ones. In addition, some cases are con?sidered in order to test the e ectiveness of the LRDM method. The results show that the solution time of the LRDM is lower than the RDM method by approximately 50%. The proposed method provides instructions for the design of more complex lattice structures.

关键词： Lattice structures Local relative density mapping Topology optimization Additive manufacturing

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