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Solvent Effects on Spectral Property and Dipole Moment of the Lowest Excited State of Coumarin 343 Dye

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Chinese Journal of Chemical Physics 2012年第5期25卷 577-584,I0004页

作者： Li-lin Jiang Wei-long Liu yun-fei Song xing He yang Wang Hong-lin Wu yan-qiang yang Center for the Condensed Matter Science and Technology Department of PhysicsHarbin Instituteof TechnologyHarbin 150001China Department of Physics and Electronics Information Engineering Hezhou UniversityHezhou 542800China

Steady-state absorption and fluorescence spectra, and time-resolved fluorescence spectra of coumarin 343 （C343） were measured in different solvents. The effect of the solvent on the spectral properties and dipole moment of the lowest excited state of C343 were investigated. It was found that the absorption and fluorescence spectra red-shifted slightly and strongly with increasing solvent polarity, respectively, because the charge distribution of the excited state leaded to the increasing difference between the absorption and fluorescence spectra with increasing solvent polarity. The dipole moment of the lowest excited state of C343 was determined from solvatochromic measurements and the quantum chemical calculation, and the results obtained from these two methods were fully consistent. Investigations of the time-resolved fluorescence of C343 in different solvents indicated that the fluorescence lifetimes increased nearly linearly with 4.45 ns in water. This can be ascribed between C343 and hydrogen donating increasing solvent polarity from 3.09 ns in toluene to to the intermolecular hydrogen bonding interactions solvents

关键词： Time-resolved fluorescence Dipole moment Solvent polarity function Quan-tum chemical calculation Intermolecular hydrogen bonding interaction

Pyrite Concretions in the Lower Cambrian Niutitang Formation,South China:Response to Hydrothermal Activity

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Journal of Earth Science 2023年第4期34卷 1053-1067页

作者： Zixuan Liu Detian yan xing Niu Key Laboratory of Tectonics and Petroleum Resources Ministry of EducationChina University of GeosciencesWuhan 430074China School of Geosciences Yangtze UniversityWuhan 434023China

The Early Cambrian Niutitang Formation is characterized by wide distribution of black shales on yangtze Block,South *** we have reported the pyrite concretions in the bottom of the Niutitang Formation deposited in the slope-basin environment of yangtze *** pyrite concretion was mainly composed of pyrite associated with hydrothermal minerals(barite,hyalophane,tetrahedrite),followed by quartz and organic *** elements Mo and U displayed significant enrichment(enrichment factors > 10),indicating the euxinic bottom water ***,Ni,and excess Ba concentrations were relatively high,denoting high primary ***-situ sulfur isotope compositions of pyrite concretions δ34Spy) showed little variations(13.2‰–19.4‰) and small fractionations compared to coeval seawater δ*** and geochemical analyses indicated the pyrite concretions were formed in the sediment-water interface during the early diagenesis,with H2S diffusing from the euxinic water,and influenced by hydrothermal activity leading to the coexistence of barite,hyalophane,and *** results imply euxinic bottom water featured by high primary productivity and increasing riverine flux of sulfate from chemical weathering during the Early Cambrian.

关键词： shale pyrites black shale pyrite concretion depositional environment.

Multi-time Collaborative Restoration for Integrated Electrical-gas Distribution Systems Based on Rolling Optimization

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 660-671页

作者： Jingyang yun Zheng yan yun Zhou Peichao Zhang Weidong Hu Key Laboratory of Control of Power Transmission and Conversion of Ministry of Education Department of Electrical EngineeringShanghai Jiao Tong University

This paper proposes a multi-time collaborative restoration model for integrated electricity-gas distribution sys-tems(IEGDSs)considering multiple resources after extreme weather *** on the linearized power flow constraints of the unbalanced electrical distribution system(EDS)and gas distribution system(GDS),this problem can be formulated as a mixed-integer linear programming(MILP)*** improve the efficiency and veracity of the solution,a rolling optimiza-tion based two-stage method is developed with the first stage solved by a linear approximation model,and the second stage solved by real-time updated rolling *** solving the MILP problem using rolling optimization,the proposed model and solution method achieve efficient and reliable collaborative restoration of IEGDS considering multiple resources and unbal-anced operation characteristics of *** effectiveness of the proposed model and method is validated by using an IEGDS made of a 37-bus unbalanced EDS and 11-node *** Terms-Electricity-gas system,mix-integer linear programming,power system restoration.

关键词： Electricity-gas system mix-integer linear programming power system restoration

Insights into Pore Structure and Fractal Characteristics of the Lower Cambrian Niutitang Formation Shale on the yangtze Platform,South China

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Journal of Earth Science 2020年第1期31卷 169-180页

作者： Zixuan Liu Detian yan xing Niu Key Laboratory of Tectonics and Petroleum Resources Ministry of EducationChina University of GeosciencesWuhan 430074China School of Earth Resources China University of GeosciencesWuhan 430074China Sedimentary Basin Research Center Yangtze UniversityWuhan 430074China

Shales from the Lower Cambrian Niutitang Formation of yangtze Platform have been widely investigated due to its shale gas *** better illustrate the pore structure and fractal characteristics of shale,a series of experiments were conducted on outcrop samples from the Lower Cambrian Niutitang Formation on yangtze Platform,including X-ray diffraction(XRD),field-emission scanning electron microscopy(FE-SEM) and low-temperature nitrogen ***-Halsey-Hill(FHH) model was adopted to calculate the fractal ***,the relationships between fractal dimensions and pore structure parameters and mineral composition are ***-SEM observation results show that interparticle pores are most developed in shale,followed by intraparticle *** study identified the fractal dimensions D1(ranging from 2.558 0 to 2.710 2) and D2(ranging from 2.541 5 to 2.765 2).The pore structure of the Niutitang Formation shale is primarily controlled by quartz and clay *** dimensions are able to characterize the pore structure complexity of Niutitang Formation shale because D1 and D2 correlate well with average pore diameter and quartz content.

关键词： Niutitang Formation yangtze area shale pore structure fractal features

SPOP negatively regulates Toll-like receptor-induced inflammation by disrupting MyD88 self-association

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Cellular & Molecular Immunology 2021年第7期18卷 1708-1717页

作者： yun-Hong Hu yang Wang Fei Wang yan-Ming Dong Wan-Ling Jiang Ya-Ping Wang xing Zhong Li-Xin Ma State Key Laboratory of Biocatalysis and Enzyme Engineering School of Life SciencesHubei UniversityWuhan430062China School of Biological and Chemical Engineering College of ZhixingHubei UniversityWuhan430011China

Toll-like receptor(TLR)signaling pathways need to be tightly controlled to avoid excessive inflammation and unwanted damage to the *** differentiation primary response gene 88(MyD88)is a critical adaptor of TLR ***,we identified the speckle-type POZ protein(SPOP)as a MyD88-associated *** was recruited to MyD88 following TLR4 ***4 activation also caused the translocation of SPOP from the nucleus to the *** depletion promoted the aggregation of MyD88 and recruitment of the downstream signaling kinases IRAK4,IRAK1 and ***,overexpression of SPOP inhibited the TLR4-mediated activation of NF-κB and production of inflammatory cytokines,whereas SPOP depletion had the opposite ***,knockdown of SPOP increased MyD88 aggregation and inflammatory cytokine production upon TLR2,TLR7 and TLR9 *** findings reveal a mechanism by which MyD88 is regulated and highlight a role for SPOP in limiting inflammatory responses.

关键词： SPOP MyD88 TLR inflammation

PXR:a center of transcriptional regulation in cancer

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Acta Pharmaceutica Sinica B 2020年第2期10卷 197-206页

作者： Yaqi xing Jiong yan Yongdong Niu Department of Pharmacology Shantou University Medical CollegeShantou 515041China Center for Pharmacogenetics University of PittsburghPA 15261USA

Pregnane X receptor(PXR,NR 112)is a prototypical member of the nuclear receptor *** can be activated by both endobiotics and *** a key xenobiotic receptor,the cellular function of PXR is mostly exerted by its binding to the regulatory gene sequences in a liganddependent *** downstream target genes of PXR participate in xenobiotic responses,such as detoxification,metabolism and *** evidence also implicates PXR signaling in the processes of apoptosis,cell cycle arrest,proliferation,angiogenesis and oxidative stress,which are closely related to ***,we discussed,in addition to the characterization of PXR per se,the biological function and regulatory mechanism of PXR signaling in cancer,and its potential for the targeted prevention and therapeutics.

关键词： PXR NR1I2 PAR Signaling Nuclear receptor Transcriptional regulation Cancer

Effects of information transmission delay and channel blocking on synchronization in scale-free Hodgkin-Huxley neuronal networks

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Acta Mechanica Sinica 2011年第6期27卷 1052-1058页

作者： Qing-yun Wang yan-Hong Zheng Department of Dynamics and Control Beihang University 100191 Beijing China School of Mathematics and Computer Science Fujian Normal University 350007 Fuzhou China

In this paper,we investigate the evolution of spatiotemporal patterns and synchronization transitions in dependence on the information transmission delay and ion channel blocking in scale-free neuronal *** the underlying model of neuronal dynamics,we use the Hodgkin-Huxley equations incorporating channel blocking and intrinsic *** is shown that delays play a significant yet subtle role in shaping the dynamics of neuronal *** particular,regions of irregular and regular propagating excitatory fronts related to the synchronization transitions appear intermittently as the delay ***,the fraction of working sodium and potassium ion channels can also have a significant impact on the spatiotemporal dynamics of neuronal *** the fraction of blocked sodium channels increases,the frequency of excitatory events decreases,which in turn manifests as an increase in the neuronal synchrony that,however,is dysfunctional due to the virtual absence of large-amplitude ***,we also show that larger coupling strengths improve synchronization irrespective of the information transmission delay and channel *** presented results are also robust against the variation of the network size,thus providing insights that could facilitate understanding of the joint impact of ion channel blocking and information transmission delay on the spatiotemporal dynamics of neuronal networks.

关键词： Scale-free neuronal networks - Information transmission delay Ion channel blocking Synchronization

Machine-learning-aided Au-based single-atom alloy catalysts discovery for electrochemical NO reduction reaction to NH_(3)

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Rare Metals 2024年第11期43卷 5813-5822页

作者： Hui-Long Jin Qian-Nan Li yun-yan Tian Shuo-Ao Wang xing Chen Jie-Yu Liu Chang-Hong Wang Hebei Provincial Key Laboratory of Information Fusion and Intelligent Control College of EngineeringHebei Normal UniversityShijiazhuang 050024China Institute of Molecular Plus School of ScienceTianjin UniversityTianjin300072China

Direct electrochemical conversion of NO to NH_(3)has attracted widespread interest as a green and sustainable strategy for both ammonia synthesis and nitric oxide ***,designing efficient catalysts remains challenging due to the complex reaction mechanism and competing side ***-atom alloy(SAA)catalysts,which increase the atomic efficiency and the chance to tailor the electronic properties of the active center,have become a frontier in this ***,we performed a systematic screening of transition metal-doped Au SAAs(denoted as TM/Au,TM=Sc,Ti,V,Cr,Mn,Fe,Co,Ni,Cu,Zn,Ru,Rh,Pd,Ag and Pt)to find potential catalysts for electrochemical NO reduction reaction(NORR)to NH_(3).By employing a four-step screening strategy based on density functional theory(DFT)calculations,Zn/Au SAA has been identified as a promising NORR catalyst due to its superior structural stability,reaction activity and NH_(3)*** electron-involved steps on Zn/Au are thermodynamically spontaneous,which results in a positive limiting potential(U_(L))of 0.15 *** preferred NO affinity compared to H adatom demonstrates that Zn/Au can effectively suppress the hydrogen evolution ***-learning(ML)investigations were adopted to address the uncertainty between the physicochemical properties of SAAs and the NORR *** applied an extreme gradient boosting regression(XGBR)algorithm to predict the limiting potentials in terms of the intrinsic features of the reaction *** coefficient of determination(R^(2))is 0.97 for the training set and 0.96 for the test *** electronic structure an alysis combined with a compressed-sensing data-an alytics approach further quantitatively verifies the coeffect of d-band center,charge transfer and the radius of doped TM atoms,i.e.,features with the highest level of importance determined by the XGBR *** work provides a theoretical understanding of the complex NORR to NH_(3)mechanisms and sheds light on the ra

关键词： NO reduction reaction Ammonia synthesis Single-atom alloy catalysts Machine learning

Effects of built-in electric field and donor impurity on linear and nonlinear optical properties of wurtzite InxGa1-xN/GaN nanostructures

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Chinese Physics B 2020年第8期29卷 479-484页

作者： Xiao-Chen yang yan xing School of Physical Science and Technology Inner Mongolia UniversityHohhot 010021China

The linear and nonlinear optical absorption coefficients(ACs)and refraction index changes(RICs)of 1s-1p,1p-1d,and 1f-1d transitions are investigated in a wurtzite InxGa1-xN/GaN core-shell quantum dot(CSQD)with donor impurity by using density matrix *** effects of built-in electric field(BEF),ternary mixed crystal(TMC),impurity,and CSQD size are studied in *** finite element method is used to calculate the ground and excited energy state energy and wave *** results reveal that the BEF has a great influence on the linear,nonlinear,and total ACs and *** presence of impurity leads the resonant peaks of the ACs and RICs to be blue-shifted for all transitions,especially for 1s-1p *** is also found that the resonant peaks of the ACs and RICs present a red shift with In-composition decreasing or core radius ***,the amplitudes of the ACs and RICs are strongly affected by the incident optical *** absorption saturation is more sensitive without the impurity than with the impurity,and the appearance of absorption saturation requires a larger incident optical intensity when considering the BEF.

关键词： core-shell quantum dot linear and nonlinear optical properties impurity ternary mixed crystal