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Fluorescence quenching and the binding interaction of lumichrome with nucleic acids

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Chinese Science Bulletin 2010年第25期55卷 2829-2834页

作者： li hui jiang ZhiQin ZHANG RongHua Department of Chemistry Tongji University Shanghai 200092 China

The interaction of lumichrome (LC) as an endogenous fluorescence probe with nucleobases,nucleosides and nucleic acids has been studied by UV-visible absorption,fluorescence spectroscopy,polarized fluorescence and viscosity. The fluorescence of LC was strongly quenched by a series of nucleic acids and their precursors. The influences of the medium,temperature and salt effects on LC-nucleobase and LC-nucleic acid complexes were investigated. The influences of polarized fluorescence,thermal denaturation and viscosity on LC-ctDNA interaction were examined. The results demonstrate that the main binding model of LC-ctDNA includes strong intercalating into the DNA helix chain.

关键词：荧光猝灭核酸结合作用相互作用机理 ctDNA 荧光探针紫外可见荧光光谱

Experimental and theoretical analysis on the procedure for estimating geo-stresses by the Kaiser effect

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 514-518页

作者： Yuan-hui li Yu-jiang Yang Jian-po liu Xing-dong Zhao College of Resources and Civil Engineering Northeastern University Shenyang 110004 China

Acoustic emission tests of the core specimens retrieved from boreholes at the depth over 1000 m in Hongtoushan Copper Mine were carried out under uniaxial compressive loading, and the numerical test was also done by using the rock failure process analysis （RFPA2D） code, based on the procedure for estimating geo-stresses by the Kaiser effect under uniaxial compression. According to the statistical damage mechanics theory, the Kaiser effect mechanism was analyzed. Based on these analyses, it is indicted that the traditional method of estimating geo-stresses by the Kaiser effect is not appropriate, and the result is usually smaller than the real one. Furthermore, the greater confining compression in the rock mass may result in a larger difference between the Kaiser effect stresses acquired from uniaxial loading in laboratory and the real in-situ stresses.

关键词： rock stresses Kaiser effect cyclic loading acoustic emission

Quinoxaline-based Polymers with Asymmetric Aromatic Side Chain Enables 16.27% Efficiency for Organic Solar Cells

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Chinese Journal of Polymer Science 2023年第7期41卷 1002-1010页

作者： Dong-Xu li Shu-Fang li Cheng-Long Wen Chao-Yuan Sun Chang-Zhou Shi Xin-Xin Xia Xin-hui Lu li-hui jiang Jun Yuan Ying-Ping Zou College of Chemistry and Chemical Engineering Central South UniversityChangsha410083China Department of Physics The Chinese University of Hong KongNew TerritoriesHong Kong999077China

In recent years, due to the rapid development of high-performance small molecule acceptor (SMA) materials, the researches on p-type electron donor materials for matching with current efficient SMAs have become important. By means of asymmetric strategies to optimize the energy levels and inter/intramolecular interactions of molecules, we designed and synthesized an asymmetric aromatic side chain quinoxaline-based polymer donor TPQ-0F. Meanwhile, we took advantage of F atom which could form noncovalent interaction and strong electron-withdrawing property, to obtain the optimized quinoxaline-based polymer donors TPQ-1F, TPQ-1Fi and TPQ-2F. Eventually, the binary device based on TPQ-2F achieved an efficient power conversion efficiency (PCE) of 16.27%, which attributed to balanced hole/electron mobilities, less charge carrier recombination, and more favorable aggregation morphology. Our work demonstrates the great potential of asymmetric aromatic side chain quinoxaline-based polymer donors on optimizing the morphology of blending films, improving inter/intramolecular interactions, and subtly tuning energy level, finally for more efficient organic solar cells.

关键词： Asymmetric aromatic side chain Quinoxaline-based polymer donor Fluorine substitution Binary device

Moderate Deviations for Parameter Estimation in the Fractional Ornstein–Uhlenbeck Processes with Periodic Mean

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1308-1324页

作者： hui jiang Shi Min li Wei Gang WANG School of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China The People's Bank of China Operations Ofice of Nanjing Branch Nanjing 210016P.R.China School of Statistics and Mathematics Zhejiang Gongshang UniversityHangzhou 310018P.R.China

In this paper,we study the asymptotic properties for the drift parameter estimators in the fractional Ornstein-Uhlenbeck process with periodic mean function and long range *** Cremér-type moderate deviations,as well ... 详细信息

关键词： Cramér-type moderate deviation fractional Ornstein-Uhlenbeck process parameter estimation multiple Wiener-Ito integrals

Regio-and Stereoselective Polymerization of Bio-based Ocimene by Rare-Earth Metal Catalysts

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Chinese Journal of Polymer Science 2024年第2期42卷 223-229,I0008页

作者： Qi-Yuan Wang li-Peng Sang Zhen Zhang Yang jiang hui Tian Xia Zhao Xiang Guo Shi-hui li State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China Science and Technology on Aerospace Chemical Power Laboratory Hubei Institute of Aerospace ChemotechonologyXiangyang441003China Shanxi Coal Chemical Industry Technology Research Institute Xi’an710000China Hubei Institute of Aerospace Chemotechonology Xiangyang441003China

Coordination polymerization of renewable β-ocimene has been investigated using asymmetric diiminophosphinate lutetium complex1, β-diketiminate yttrium complex 2, bis(phosphino)carbazolide yttrium complex 3, half-sandwich benzyl fluorenyl scandium complex 4 and pyridyl-methylene-fluorenyl rare-metal complexes 5a–5c. Complexes 1, 4 and 5a–5c show trans-1,2-regioselectivities and high activities, of which 5c exhibits excellent isoselectivity(mmmm>99%). Conversely, complexes 2 and 3 promote β-ocimene polymerization to produce isotactic cis-1,4-polyocimenes(cis-1,4>99%, mm>95%). Diblock copolymers cis-1,4-PIP-block-cis-1,4-POc and cis-1,4-PBD-block-cis-1,4-POc are obtained in one-pot reactions of β-ocimene with isoprene and butadiene using complex 3. Epoxidation and hydroxylation of polyocimene afford functionalized polyolefins with enhanced T_(g)(from-20 ℃ to 79 ℃ and 74 ℃) and hydrophilicity.

关键词： Biobased monomer Terpenes Ocimene Rare-earths Polymerization Regio/stereoselectivity Elastomer

Comparison of debris flow susceptibility assessment methods:support vector machine,particle swarm optimization,and feature selection techniques

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Journal of Mountain Science 2024年第2期21卷 397-412页

作者： ZHAO Haijun WEI Aihua MA Fengshan DAI Fenggang jiang Yongbing li hui Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China Hebei Province Key Laboratory of Sustained Utilization&Development of Water Recourse Hebei GEO UniversityShijiazhuang 050031China School of Water Resources and Environment Hebei GEO UniversityShijiazhuang 050031China The Sixth Geological Brigade of Geological Mineral Exploration and Development Bureau of Hebei Province Shijiazhuang 050085China

The selection of important factors in machine learning-based susceptibility assessments is crucial to obtain reliable susceptibility *** this study,metaheuristic optimization and feature selection techniques were applied to identify the most important input parameters for mapping debris flow susceptibility in the southern mountain area of Chengde City in Hebei Province,China,by using machine learning *** total,133 historical debris flow records and 16 related factors were *** support vector machine(SVM)was first used as the base classifier,and then a hybrid model was introduced by a two-step ***,the particle swarm optimization(PSO)algorithm was employed to select the SVM model ***,two feature selection algorithms,namely principal component analysis(PCA)and PSO,were integrated into the PSO-based SVM model,which generated the PCA-PSO-SVM and FS-PSO-SVM models,*** statistical metrics(accuracy,recall,and specificity)and the area under the receiver operating characteristic curve(AUC)were employed to evaluate and validate the performance of the *** results indicated that the feature selection-based models exhibited the best performance,followed by the PSO-based SVM and SVM ***,the performance of the FS-PSO-SVM model was better than that of the PCA-PSO-SVM model,showing the highest AUC,accuracy,recall,and specificity values in both the training and testing *** was found that the selection of optimal features is crucial to improving the reliability of debris flow susceptibility assessment ***,the PSO algorithm was found to be not only an effective tool for hyperparameter optimization,but also a useful feature selection algorithm to improve prediction accuracies of debris flow susceptibility by using machine learning *** high and very high debris flow susceptibility zone appropriately covers 38.01%of the study area,where debris flow may occur under intens

关键词： Chengde Feature selection Support vector machine Particle swarm optimization Principal component analysis Debris flow susceptibility

Wireless Positioning:Technologies,Applications,Challenges,and Future Development Trends

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1135-1166页

作者： Xingwang li Hua Pang Geng li Junjie jiang hui Zhang Changfei Gu Dong Yuan School of Physics and Electronic Information Engineering University of Henan PolytechnicJiaozuo454000China Jiaozuo Key Laboratory of Crow-Sensing Network Jiaozuo454000China Institute of Mining Engineering Guizhou Institute of TechnologyGuiyang550003China Coal Supervision Department Panzhou Energy BureauPanzhou553599China

The development of the fifth-generation(5G)mobile communication systems has entered the commercialization stage.5G has a high data rate,low latency,and high reliability that can meet the basic demands of most industries and daily life,such as the Internet of Things(IoT),intelligent transportation systems,positioning,and *** continuous progress and development of society have aroused wide *** accuracy is the core demand for the applications,especially in complex environments such as airports,warehouses,supermarkets,and ***,many factors also affect the accuracy of positioning in those environments,for example,multipath effects,non-line-of-sight,and clock synchronization *** paper provides a comprehensive review of the existing works about positioning for the future wireless network and discusses its key techniques and algorithms,as well as the current development and future *** first outline the current traditional positioning technologies and algorithms,which are discussed and analyzed with the relevant *** addition,we also discuss application scenarios for wireless *** comparing different positioning systems,the challenges and future development directions of existing wireless positioning systems are prospected.

关键词： 5G wireless positioning reconfigurable intelligent surface Internet of Vehicles

Energy beam-based direct and assisted polishing techniques for diamond:A review

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International Journal of Extreme Manufacturing 2024年第1期6卷 93-124页

作者： Zhuo li Feng jiang Zhengyi jiang Zige Tian Tian Qiu Tao Zhang Qiuling Wen Xizhao Lu Jing Lu hui Huang Institute of Manufacturing Engineering Huaqiao UniversityXiamen 361021People’s Republic of China School of Mechanical MaterialsMechatronic and Biomedical EngineeringUniversity of WollongongWollongongNSW 2522Australia College of Mechanical Engineering and Automation Huaqiao UniversityXiamen 361021People’s Republic of China State Key Laboratory of High Performance Tools Huaqiao UniversityXiamen 361021People’s Republic of China

Diamond is a highly valuable material with diverse industrial applications,particularly in the fields of semiconductor,optics,and high-power ***,its high hardness and chemical stability make it difficult to realize high-efficiency and ultra-low damage machining of *** address these challenges,several polishing methods have been developed for both single crystal diamond(SCD)and polycrystalline diamond(PCD),including mechanical,chemical,laser,and ion beam processing *** this review,the characteristics and application scope of various polishing technologies for SCD and PCD are ***,various energy beam-based direct and assisted polishing technologies,such as laser polishing,ion beam polishing,plasma-assisted polishing,and laser-assisted polishing,are *** current research progress,material removal mechanism,and infuencing factors of each polishing technology are *** some of these methods can achieve high material removal rates or reduce surface roughness,no single method can meet all the ***,the future development prospects and application directions of different polishing technologies are presented.

关键词： single crystal diamond polycrystalline diamond energy beam polishing technology material removal mechanism influencing factors

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Neg-Entropy Mechanism as a Target for Natural Medicines

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Engineering 2024年第7期38卷 11-12页

作者： Tian-Le Gao hui-hui Guo Jian-Dong jiang Institute of Materia Medica Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

Current strategies for drug discovery research mainly focus on molecular targets,in which structure biology plays a central role,such as the detailed mechanism of a drug-target *** principle of this approach is the presumed molecular mechanism or genetic background of the disease being *** this approach has brought progress in understanding the mode of action for some drugs,most prevalent illnesses-especially chronic diseases-are multifactorial and present with a group of symptoms,as is often the case in cardiovascular diseases,metabolic disorders,cancers,and so *** newly emerging term“multi-morbidity”(i.e.,multiple co-occurring diseases)describes a grand challenge for this strategy,and successful drug intervention for multimorbidity should be multifaceted[1].So,our research team has shifted its attention to a new direction that views the disease as a whole instead of a single-molecule abnormality,and focusing on drugs with multiple targets.

关键词： drugs diseases cardiovascular