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New Triterpenes from Siyekucai (Ixeris chinensis)

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Chinese Chemical Letters 2006年第2期17卷 195-197页

作者： Shu Jun ZHANG Jin Lan WANG qi gang deng Masayoshi ANDO Department of Chemistry and Engineering qiqihar University Qiqihar 161006 Niigata University Ikarashi 2-8050 Niigata 950-2181 Japan

Three new triterpenes, 3β,21α-dihydroxylupen-18（19）-en （1）, 3β,25-dihydroxytirucalla- 7,23（24）-dien （2）, and 21α-hydroxy-19α-hydrogentaraxastero1-20（30）-en （3） were obtained from an ethyl acetate extract of the whole plant of Siyekucai （Ixeris chinensis）. The structures of 1-3 were determined by spectroscopic methods （EIMS, IR, 1D and 2D NMR）.

关键词： Ixeris chinensis trierpene 3β 21α-dihydroxylupen-18(19)-en (1) 3β 25-dihydroxy-tirucalla-7 23(24)-dien 21α-hydroxy-19α-hydrogentaraxastero1-20(30)-en.

Synthesis,fluorescence properties and selective Cr(Ⅲ) recognition of tetraaryl imidazole derivatives bearing thiazole group

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Chinese Chemical Letters 2013年第3期24卷 257-259页

作者： Bing Zhao Ya-Cui Zhou Meng-liao Fan Zhi-Yu Li Li-Yan Wang qi-gang deng Chemistry and Chemical Engineering Institute Qiqihar University

Three tetraaryl imidazole derivatives 5a-5c bearing thiazole groups were synthesized in the presence of [Bmin]Br by one-pot reaction and their structures were fully characterized by the H NMR, IR, MS and elemental analysis. The results of UV-vis spectra and fluorescent spectra upon metal ions complexation show that compound 5a displays high selectivity and sensitivity for Cr3＋ ions. The complexation ratio of compound 5a and Cr3＋ is 1：1.

关键词： Tetraaryl imidazoleThiazoleFluorescentSelectivity Cr3+

The Orthogonal Bases of Exponential Functions Based on Moran-Sierpinski Measures

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1804-1824页

作者： qi Rong deng Xing gang HE Ming Tian LI Yuan Ling YE School of Mathematics and Statistics Center for Applied Mathematics of Fujian Province&Key Laboratory of Analytical Mathematics and Applications(Ministry of Education)Fujian Normal UniversityFuzhou350117P.R.China School of Mathematics and Statistics Key Lab NAA-MOE and Hubei Key Lab-Math.Sci.Central China Normal UniversityWuhan430079P.R.China School of Mathematical Sciences&South China Research Center for Applied Mathematics and Interdisciplinary Studies South China Normal UniversityGuangzhou510631P.R.China

Let An∈M2(ℤ)be integral matrices such that the infinite convolution of Dirac measures with equal weightsμ{A_(n),n≥1}δA_(1)^(-1)D*δA_(1)^(-1)A_(2)^(-2)D*…is a probability measure with compact support,where D={(0,0)^(t),(1,0)^(t),(0,1)^(t)}is the Sierpinski *** prove that there exists a setΛ⊂ℝ2 such that the family{e2πi〈λ,x〉:λ∈Λ} is an orthonormal basis of L^(2)(μ{A_(n),n≥1})if and only if 1/3(1,-1)A_(n)∈Z^(2)for n≥2 under some metric conditions on A_(n).

关键词： Moran-Sierpinski measures orthonormal basis of exponential functions self-affine measures spectral measures

State-sensitive convolutional sparse coding for potential biomarker identification in brain signals

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Science China(Information Sciences) 2024年第5期67卷 270-286页

作者： Puli WANG Yu qi gang PAN College of Computer Science and Technology Zhejiang University State Key Laboratory of Brain-Machine Intelligence Zhejiang University MOE Frontier Science Center for Brain Science and Brain-machine Integration Zhejiang University Affiliated Mental Health Center & Hangzhou Seventh People's Hospital Zhejiang University School of Medicine

The identification of prototypical waveforms, such as sleep spindles and epileptic spikes, is crucial for the diagnosis of neurological disorders. These prototypical waveforms are usually recurrently presented in certain brain states, serving as potential biomarkers for clinical evaluations. Convolutional sparse coding(CSC) approaches have demonstrated strength in identifying recurrent patterns in time-series. However,existing CSC approaches do not explicitly explore state-specific patterns, making it difficult to identify state-related biomarkers. To address this problem, we propose state-sensitive CSC to learn state-specific prototypical waveforms. Specifically, we model signals of a certain state with specific waveforms that only appear frequently in this state and background waveforms that are independent of states. Based on this,state-sensitive CSC separates state-specific waveforms from background ones explicitly by incorporating incoherence constraints into optimizations. Experiments with epilepsy brain signals demonstrate that our approach can effectively identify prototypical waveforms in pre-ictal states, providing potential biomarkers for seizure prediction. Our approach provides a promising tool for automatic biomarker candidate identification.

关键词： convolutional sparse coding prototypical waveforms state-specific dictionary biomarker identification neural signal processing

Single-atom catalysts supported on graphene/electride heterostructures for the enhanced sulfur reduction reaction in lithium-sulfur batteries

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Journal of Energy Chemistry 2024年第10期97卷 738-746,I0015页

作者： Siyun qi Chuanchuan Li gang Chen Mingwen Zhao School of Physics and Electronics Shandong Normal UniversityJinan 250358ShandongChina qingdao Industrial Energy Storage Research Institute Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 26611ShandongChina School of Physics&State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100ShandongChina

Single-atom catalysts(SACs)hold great promise in addressing the sluggish kinetics of the sulfur reduction reaction(SRR)in lithium-sulfur(Li-S)batteries for their unique catalytic activity and maximum atom *** these SACs must be dispersed on solid substrates,the underlying support is usually limited to carbon materials that have a poor ability to modulate the coordination environment and electronic structures of single atoms,and consequently their catalytic activity toward the SRR is *** we propose two-dimensional(2D)graphene/electride heterostructu res as substrates to enhance the catalytic activities of SACs for Li-S batteries.2D electrides featuring the anionic electron gas on their surface enable efficient electron transfer to SACs,which alters their electronic structures,resulting in the shifts of the d orbital and Fermi *** unique electronic structure decreases the filling of antibonding states such that the bonding with adsorbates at active sites is *** demonstrate the enhanced catalytic performance of SACs in terms of the Gibbs free energy of SRR and Li_(2)S *** addition,a universal descriptor for the rapid screening of SACs is established by a linear regression fitting *** work provides a new design strategy to modulate SAC activity through electrides for Li-S batteries.

关键词： Electrides DFT calculations Kinetics Universal descriptors Charge transfers

Construction of wavelength-tunable DSE quinoline salt derivatives by regulating the hybridization form of the nitrogen atom and intramolecular torsion angle

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Chinese Chemical Letters 2024年第10期35卷 315-320页

作者： Kuan deng Fei Yang Zhi-qi Cheng Bi-Wen Ren Hua Liu Jiao Chen Meng-Yao She Le Yu Xiao-gang Liu Hai-Tao Feng Jian-Li Li Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education Shaanxi Key Laboratory for Carbon Neutral TechnologyCollege of Chemistry&Materials ScienceNorthwest UniversityXi'an710127China Key Laboratory of Resource Biology and Biotechnology in Western China Ministry of EducationBiomedicine Key Laboratory of Shaanxi ProvinceLab of Tissue Engineeringthe College of Life SciencesFaculty of Life Science&MedicineNorthwest UniversityXi'an 710069China Fluorescence Research Group Singapore University of Technology and DesignSingapore 487372Singapore Baoji AIE Research Center Shanxi Key Laboratory of PhytochemistryCollege of Chemistry and Chemical EngineeringBaoji University of Arts and SciencesBaoji721013China

Dual-state emission(DSE)molecules displayed conspicuous fluorescent performance both in solid and solution ***,the construction of DSE molecules and the regulation of their emission wavelengths remains a great *** on the structure-function relationship of quinolinonitrile-type fluorophores,this work proposed a feasible strategy for modulating their fluorescent properties into DSE via limiting the torsion angle between the quinoline ring and C=C bond in the range of 4.7°to 30°.Based on this strategy,53 compounds were obtained which displayed tunable emission wavelengths from^(3)97 nm to 740 nm in solid-state and from 360 nm to 672 nm in *** feasibility of the strategy was supported by a series of theoretical calculations,optical characterizations,and crystal analysis,suggesting the compounds have great potential in imaging living cells and tissues with desired wavelengths.

关键词： Fluorescence Dual-state emission Structure-function relationship Wavelength regulation Fluorescent imaging

Differences and identification on multi-time hydrocarbon generation of carboniferous-permian coaly source rocks in the Huanghua Depression,Bohai Bay Basin

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Petroleum Science 2024年第2期21卷 765-776页

作者： Jin-Jun Xu Xian-gang Cheng Shu-Nan Peng Jun-Cai Jiang qi-Long Wu Da Lou Fu-qi Cheng La-Mei Lin National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580ShandongChina PetroChina Dagang Oilfield Company Tianjin300280China

Coal is a solid combustible mineral,and coal-bearing strata have important hydrocarbon generation potential and contribute to more than 12%of the global hydrocarbon ***,the deposition and hydrocarbon evolution process of ancient coal-bearing strata is characterized by multiple geological times,leading to obvious distinctions in their hydrocarbon generation potential,geological processes,and production,which affect the evaluation and exploration of hydrocarbon resources derived from coaly source rocks *** study aimed to identify the differences on oil-generated parent macerals and the production of oil generated from different coaly source rocks and through different oil generation *** with the analysis of previous tectonic burial history and hydrocarbon generation history,high-temperature and high-pressure thermal simulation experiments,organic geochemistry,and organic petrology were performed on the Carboniferous-Permian(C-P)coaly source rocks in the Huanghua Depression,Bohai Bay *** oil-generated parent macerals of coal's secondary oil generation process(SOGP)were mainly hydrogen-rich collotelinite,collodetrinite,sporinite,and cutinite,while the oil-generated parent macerals of tertiary oil generation process(TOGP)were the remaining small amount of hydrogen-rich collotelinite,sporinite,and cutinite,as well as dispersed soluble organic matter and unexhausted residual *** with coal,the oil-generated parent macerals of coaly shale SOGP were mostly sporinite and *** part of hydrogen-poor vitrinite,lacking hydrocarbon-rich macerals,and macerals of the TOGP,in addition to some remaining cutinite and a small amount of crude oil and bitumen from SOGP contributed to the oil *** results indicated that the changes in oil yield had a good junction between SOGP and TOGP,both coal and coaly shale had higher SOGP aborted oil yield than TOGP starting yield,and coaly shale TOGP peak oil yield was low

关键词： Thermal simulation Multi-time oil generation processes Coaly source rock Carboniferous-permian Huanghua Depression

Long-term ocean temperature trend and marine heatwaves

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Journal of Oceanology and Limnology 2024年第4期42卷 1037-1047页

作者： Min ZHANG Yangyan CHENG gang WANG qi SHU Chang ZHAO Yuanling ZHANG Fangli qiAO First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Key Laboratory of Marine Sciences and Numerical Modelling Ministry of Natural ResourcesQingdao 266061China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China

Marine heatwaves(MHWs)can cause irreversible damage to marine ecosystems and *** MHW characterization remains difficult,because the choice of a sea surface temperature(SST)temporal baseline strongly influences MHW *** a recent work suggesting that there should be a communicating baseline for long-term ocean temperature trends(LTT)and MHWs,we provided an effective and quantitative solution to calculate LTT and MHWs simultaneously by using the ensemble empirical mode decomposition(EEMD)*** long-term nonlinear trend of SST obtained by EEMD shows superiority over the traditional linear trend in that the data extension does not alter prior *** MHWs identified from the detrended SST data exhibited low sensitivity to the baseline choice,demonstrating the robustness of our *** also derived the total heat exposure(THE)by combining LTT and *** THE was sensitive to the fixed-period baseline choice,with a response to increasing SST that depended on the onset time of a perpetual MHW state(identified MHW days equal to the year length).Subtropical areas,the Indian Ocean,and part of the Southern Ocean were most sensitive to the long-term global warming trend.

关键词： marine heatwaves(MHWs) ensemble empirical mode decomposition(EEMD) long-term temperature(LTT)trend total heat exposure(THE)

Resilience Augmentation in Unmanned Weapon Systems via Multi-Layer Attention Graph Convolutional Neural Networks

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Computers, Materials & Continua 2024年第8期80卷 2941-2962页

作者： Kexin Wang Yingdong Gou Dingrui Xue Jiancheng Liu Wanlong qi gang Hou Bo Li Northwest Institute of Mechanical and Electrical Engineering Xianyang712099China

The collective Unmanned Weapon System-of-Systems(UWSOS)network represents a fundamental element in modern warfare,characterized by a diverse array of unmanned combat platforms interconnected through hetero-geneous network *** its strategic importance,the UWSOS network is highly susceptible to hostile infiltrations,which significantly impede its battlefield recovery *** methods to enhance network resilience predominantly focus on basic graph relationships,neglecting the crucial higher-order dependencies among nodes necessary for capturing multi-hop meta-paths within the *** address these limitations,we propose the Enhanced-Resilience Multi-Layer Attention Graph Convolutional Network(E-MAGCN),designed to augment the adaptability of *** approach employs BERT for extracting semantic insights from nodes and edges,thereby refining feature representations by leveraging various node and edge ***,E-MAGCN integrates a regularization-based multi-layer attention mechanism and a semantic node fusion algo-rithm within the Graph Convolutional Network(GCN)*** extensive simulation experiments,our model demonstrates an enhancement in resilience performance ranging from 1.2% to 7% over existing algorithms.

关键词： Resilience enhancement heterogeneous network graph convolutional network