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National Science Review 2017年第2期4卷 224-239页

作者： Zhigang Shuai qian peng MOE Key Laboratory of Organic Optoelectronics and Molecular Engineering Department of ChemistryTsinghua University CAS Key Laboratory of Organic Solids Institute of ChemistryChinese Academy of Sciences

Theoretical understanding of organic light-emitting diodes started from the quest to the nature of the primary excitation in organic molecular and polymeric materials. We found the electron correlation strength, bond-length alternation as well as the conjugation extent have strong influences on the orderings of the lowest lying excited states through the first application of density matrix renormalization group theory to quantum chemistry. The electro-injected free carriers(with spin 1/2) can form both singlet and triplet bound states. We found that the singlet exciton formation ratio can exceed the conventional 25% spin statistics limit. We proposed a vibration correlation function formalism to evaluate the excited-state decay rates, which is shown to not only give reasonable estimations for the quantum efficiency but also a quantitative account for the aggregation-induced emission(AIE). It is suggested to unravel the AIE mechanism through resonance Raman spectroscopy.

关键词： excited-state theory organic electroluminescence spin statistics quantum efficiency vibration correlation function

Targeting H3K36 methyltransferases NSDs:a promising strategy for tumor targeted therapy

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Signal Transduction and Targeted Therapy 2021年第7期6卷 1933-1934页

作者： Xuerun peng qian peng Lei Zhong Personalized Drug Therapy Key Laboratory of Sichuan Province Department of PharmacySichuan Provincial People's HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengduSichuanChina Radiation Oncology Key Laboratory of Sichuan Province Sichuan Cancer Hospital&InstituteSichuan Cancer CenterSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengduChina

Recently,two studies published in Nature identified genetic changes in the nuclear receptor-binding SET domain protein(NSD)family of histone methyltransferases as oncogenic drivers in some malignancies,and revealed th... 详细信息

关键词： methyltransferase targeted therapy

Correlating learning and memory improvements to long-term potentiation in patients with brain injury

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Neural Regeneration Research 2008年第2期3卷 172-176页

作者： Xingfu peng qian Yu Department of Rehabilitation Medicine Affiliated Hospital of Luzhou Medical College Luzhou 646000 Sichuan Province China

BACKGROUND： Brain injury patients often exhibit learning and memory functional deficits. Long-term potentiation （LTP） is a representative index for studying learning and memory cellular models; the LTP index correlates to neural plasticity. OBJECTIVE： This study was designed to investigate correlations of learning and memory functions to LTP in brain injury patients, and to summarize the research advancements in mechanisms underlying brain functional improvements after rehabilitation intervention. RETRIEVAL STRATEGY： Using the terms ＂brain injuries, rehabilitation, learning and memory, long-term potentiation＂, manuscripts that were published from 2000-2007 were retrieved from the PubMed database. At the same time, manuscripts published from 2000-2007 were also retrieved from the Database of Chinese Scientific and Technical Periodicals with the same terms in the Chinese language. A total of 64 manuscripts were obtained and primarily screened. Inclusion criteria： studies on learning and memory, as well as LTP in brain injury patients, and studies focused on the effects of rehabilitation intervention on the two indices; studies that were recently published or in high-impact journals. Exclusion criteria： repetitive studies. LITERATURE EVALUATION： The included manuscripts primarily focused on correlations between learning and memory and LTP, the effects of brain injury on learning and memory, as well as LTP, and the effects of rehabilitation intervention on learning and memory after brain injury. The included 39 manuscripts were clinical, basic experimental, or review studies. DATA SYNTHESIS： Learning and memory closely correlates to LTP. The neurobiological basis of learning and memory is central nervous system plasticity, which involves neural networks, neural circuits, and synaptic connections, in particular, synaptic plasticity. LTP is considered to be an ideal model for studying synaptic plasticity, and it is also a classic model for studying neural plasticity

关键词： learning and memory brain injury long-term potentiation rehabilitation

Overriding the inherent alkalinity to dual phosphinito bimetallic catalyst for C(sp^(2))-C(sp^(3))formation:A combined computational and experimental study

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Chinese Chemical Letters 2023年第8期34卷 147-152页

作者： Sujuan Zheng Heng Zhang qian peng State Key Laboratory of Elemento-Organic Chemistry Tianjin Key Laboratory of Biosensing and Molecular RecognitionFrontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable Chemical Transformation Tianjin 300192China

Unraveling the catalytic reaction mechanism is a long-term challenge for developing efficient *** blooming bimetallic catalyst have enabled to activate inert bonds and realize complex C-C ***,we theoretically discover a dual-phosphinito bridged hetero-bimetallic species that verified by NMR *** results indicate only dual-phosphinito Ni-Al model can be an active catalyst in asymmetric cycloadditions via C-C activation and C-H activation,which can well rationalize the experimental observations for both reactivity and *** unprecedented tandem redox dehydrogenation mechanism was revealed to control the formation of this active species overriding the inherent *** Lewis acid and eg orbital interactions,including dz2 orbital reoccupation and d_(x^(2)−y^(2))orbital recombination,were disclosed to understand both thermodynamic and kinetic advance of dual-bridged model,displaying feasible redox properties.

关键词： Ni-Al bimetallic catalysis Secondary phosphine oxides Redox dehydrogenation Dual-SPO model

Molecular mechanism of aggregation-induced emission

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Aggregate 2021年第5期2卷 151-170页

作者： qian peng Zhigang Shuai School of Chemical Sciences University of Chinese Academy of SciencesBeijingChina Kay Laboratory of Organic Solids and Beijing National Laboratory for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijingChina MOE Key Laboratory of Organic OptoElectronics and Molecular Engineering Department of ChemistryTsinghua UniversityBeijingChina

Deep understanding of the inherent luminescence mechanism is essential for the development of aggregation-induced emission(AIE)materials and *** first note that the intermolecular excitonic coupling is much weaker in strength than the intramolecular electron-vibration coupling for a majority of newly termed AIEgens,which leads to the emission peak position insensitive to excitonic coupling,hence the conventional excitonic model for J-aggregation cannot effectively explain their AIE ***,using multiscale computational approach coupled with our self-developed thermal vibration correlation function rate formalism and transition-state theory,we quantitatively investigate the aggregation effect on both the radiative and the nonradiative decays of molecular excited *** radiative decay processes,we propose that the lowest excited state could convert from a transition dipole-forbidden“dark”state to a dipole-allowed“bright”state upon *** the radiationless processes,we demonstrate the blockage of nonradiative decay via vibration relaxation(BNR-VR)in harmonic region or the removal of nonradiative decay via isomerization(RNR-ISO)or minimum energy crossing point(RNR-MECP)beyond harmonic region in a variety of AIE *** theoretical work not only justifies a plethora of experimental results but also makes reliable predictions on molecular design and mechanism that can be experimentally *** forward,we believe this review will benefit the deep understanding about the universality of AIE phenomenon and further extending the scope of AIE systems with novel applications.

关键词： aggregation-induced emission dipole-allowed bright state minimum energy crossing point nonradiative decay vibration relaxation

Promoting-mode free formalism for excited state radiationless decay process with Duschinsky rotation effect

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Science China Chemistry 2008年第12期51卷 1153-1158页

作者： NIU YingLi peng qian SHUAI ZhiGang Key Laboratory of Organic Solids Beijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of SciencesBeijing 100190China Department of Chemistry Tsinghua UniversityBeijing 100084China

In the present work, through the path integral of Gaussian type correlation function, a new formalism based on Fermi-Golden Rule for calculating the rate constant of nonradiative decay process with Duschinsky rotation effect in polyatomic molecules is developed. The advantage of the present path-integral formalism is promoting-mode free. In order to get the rate constant, a "transition rate matrix" needs to be calculated. The rate constant calculated previously is only an approximation of diagonal elements of our "transition rate matrix " . The total rate should be the summation over all the matrix elements.

关键词： Duschinsky rotation radiationless decay correlation function path integral promoting-mode free

The homogenous growth of Co-based coordination compound on graphene nanosheet for high-performance K-organic battery and its reaction mechanism

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Rare Metals 2024年第4期43卷 1622-1634页

作者： qian-qian peng Yi-Ting Wang Shuo Qi Yao Xiao Yong Wang Shuang-qiang Chen School of Environmental and Chemical Engineering Shanghai UniversityShanghai200444China School of Chemistry and Materials Engineering Wenzhou UniversityWenzhou325035China

Metal coordination compounds(MCCs)are gaining popularity for potassium-ion batteries(PIBs)owing to their tuneable structure,multiple reaction sites,low cost and unique ***,they are generally subjected to intrinsic features of the sluggish ionic diffusion coefficient,low electronic conductivity and slow ***,a new MCC material of cobalt-1,3,5-trioxy-2,4,6-triamino-benzo(Co-TB)coordination compound was synthesized and homogenously grown on the surface of graphene nanosheets(GNS),forming a Co-TB@GNS composite with enhanced electronic conductivity and flexible *** from the overall enhanced conductivity,high surface area and abundant activated K-storage sites,Co-TB@GNS electrodes have exhibited superior cycling performance with high reversible capacities(312 mAh·g^(-1)after 100 cycles at 100 mA·g^(-1),224 mAh·g^(-1)after 500 cycles at 1 A·g^(-1))and better rate performances compared with the pure Co-TB compound when served as PIB's ***,multiple in-situ measurement techniques have jointly confirmed that the organic functional groups(C=O,C=N and C=C of benzene rings)and Co^(2+)in Co-TB are the main reversible K-storage sites,including in-situ Fourier transform infrared spectroscopy(FTIR)and X-ray diffraction(XRD),and partial capacity contribution is originated from GNS by the apparent K-storage behavior in the in-situ XRD pattern,proving the possibility of K-storage for metal-organic materials.

关键词： Metal coordination compounds Potassiumion battery Cobalt coordination compound K-storage mechanism

From electronic excited state theory to the property predictions of organic optoelectronic materials

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Science China Chemistry 2013年第9期56卷 1277-1284页

作者： SHUAI ZhiGang XU Wei peng qian GENG Hua MOE Key Laboratory of Organic Optoelectronics and Molecular Engineering Department of ChemistryTsinghua University Key Laboratory of Organic Solids Beijing National Laboratory for Molecular ScienceInstitute of ChemistryChinese Academy of Sciences

We introduce here a work package for a National Natural Science Foundation of China Major Project. We propose to develop computational methodology starting from the theory of electronic excitation processes to predicting the opto-electronic property for organic materials, in close collaborations with experiments. Through developing methods for the electron dynamics, considering superexchange electronic couplings, spin-orbit coupling elements between excited states, electron-phonon relaxation, intermolecular Coulomb and exchange terms we combine the statistical physics approaches including dynamic Monte Carlo, Boltzmann transport equation and Boltzmann statistics to predict the macroscopic properties of opto-electronic materials such as light-emitting efficiency, charge mobility, and exciton diffusion length. Experimental synthesis and characterization of D-A type ambipolar transport material as well as novel carbon based material will provide a test ground for the verification of theory.

关键词： electron dynamics methods statistical physics approaches light-emitting efficiency charge mobility exciton diffusion

Multi-Objective Optimization of Aluminum Alloy Electric Bus Frame Connectors for Enhanced Durability

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 735-755页

作者： Wenjun Zhou Mingzhi Yang qian peng Yong peng Kui Wang qiang Xiao Key Laboratory of Traffic Safety on Track Ministry of EducationSchool of Traffic&Transportation EngineeringCentral South UniversityChangsha410018China School of Mechanical and Automotive Engineering Xiamen University of TechnologyXiamen361024China

The widespread adoption of aluminumalloy electric buses,known for their energy efficiency and eco-friendliness,faces a challenge due to the aluminum frame’s susceptibility to deformation compared to *** issue is further exacerbated by the stringent requirements imposed by the flammability and explosiveness of batteries,necessitating robust frame *** study aims to optimize the connectors of aluminum alloy bus frames,emphasizing durability,energy efficiency,and *** research delves into Multi-Objective Coordinated Optimization(MCO)techniques for lightweight design in aluminum alloy bus body *** goal is to enhance lightweighting,reinforce energy absorption,and improve deformation resistance in connector *** typical aluminum alloy connectors were selected and a design optimization platform was built for their MCO using a variety of software and ***,through three-point bending experiments and finite element analysis on three types of connector components,we identified optimized design parameters based on deformation ***,employing Optimal Latin hypercube design(OLHD),parametric modeling,and neural network approximation,we developed high-precision approximate models for the design parameters of each connector component,targeting energy absorption,mass,and logarithmic ***,utilizing the Archive-based Micro Genetic Algorithm(AMGA),Multi-Objective Particle Swarm Optimization(MOPSO),and Non-dominated SortingGenetic Algorithm(NSGA2),we explored optimized design solutions for these joint ***,we simulated joint assembly buckling during bus rollover crash scenarios to verify and analyze the optimized solutions in three-point bending *** joint component showcased a remarkable 30%–40%mass reduction while boosting energy *** design optimization method exhibits high efficiency and *** contemporary automation technology,the design optimiza

关键词： Aluminum connectors three-point bending simulation parametric design model multi-objective collaborative optimization

Dynamics of arsenic in salt marsh sediments from Dongtan wetland of the Yangtze River estuary,China

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Journal of Environmental Sciences 2012年第12期24卷 2113-2121页

作者： Yongjie Wang Limin Zhou Xiangmin Zheng peng qian Yonghong Wu Department of Geography College of Resources and Environmental SciencesEast China Normal UniversityShanghai 200062China School of Geography Nantong UniversityNantong 226019China Department of Gography Minfiang UniversityFuzhou 350108China

The mobility and transformation of arsenic （As） in salt marsh sediments were investigated in Dongtan wetland of the Yangtze River estuary, China. As in surface water, pore water and the rhizosphere sediments were quantified. The microcosm incubation experiments were conducted during the flooding of the sediments to examine As dynamics that occurred during changing redox conditions. The concentrations of dissolved As in pore water （0.04--0.95 ixmol/L） were significantly greater than that in surface water （0.03-0.06 lunol/L）. Under anoxic conditions, the reactive As could be initially mobilized by the reductive dissolution of Fe（III）（hydr）oxides. Subsequently, most of the dissolved As was likely to be associated with secondary iron （hydr）oxide phases and remained in solid phases. The seasonal variability of acid volatile sulfide concentrations suggest the anoxic conditions are enhanced during summer by Spartina alterniflora compared to Phragmites australis and Scirpus mariqueter, causing a notable increase in As mobility. Generally, there was a typical variation in redox conditions with season in salt marsh sediments of Dongtan wetland, in which the dynamics of As mobility and transformation possibly were controlled by iron, and all of this could be significantly influenced by the rapid spread of S. alterniflora.

关键词： Arsenic iron (hydr)oxides salt marsh sediment Spartina alterniflora Yangtze River estuary