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Defects Energetics and Electronic Properties of Li Doped ZnO： A Hybrid Hartree-Fock and Density Functional Study

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chinese Journal of chemical Physics 2012年第3期25卷 261-268,373页

作者： Xu sun You-song Gu Xue-qiang Wang yue Zhang Department of Material Physics and chemist04 University of Science and Technology Beijing Beij'ing100083 China

The electronic properties and stability of Li-doped ZnO with various defects have been stud- ied by calculating the electronic structures and defect formation energies via first-principles calculations using hybrid Hartree-Fock and density functional methods. The results from formation energy calculations show that Li pair complexes have the lowest formation energy in most circumstances and they consume most of the Li content in Li doped ZnO, which make the p-type conductance hard to obtain. The formation of Li pair complexes is the main obstacle to realize p-type conductance in Li doped ZnO. However, the formation energy of Lizn decreases as environment changes from Zn-rich to O-rich and becomes more stable than that of Li-pair complexes at highly O-rich environment. Therefore, p-type conductance can be obtained by Li doped ZnO grown or post annealed in oxygen rich atmosphere.

关键词： Li doped ZnO Multi-defects Hybrid density functional

Assimilating Doppler radar observations with an ensemble Kalman filter for convection-permitting prediction of convective development in a heavy rainfall event during the pre-summer rainy season of South china

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Science china Earth Sciences 2017年第10期60卷 1866-1885页

作者： BAO XingHua LUO YaLi sun JiaXiang MENG ZhiYong yue Jian State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China collaborative Innovation center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology Nanjing 210044 China cAAc East china Regional Air Traffic Administration Shanghai 200335 China Laboratory for climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic Sciences School of Physics Peking University Beijing 100871 China National Meteorological center China Meteorological Administration Beijing 100081 China

This study examines the effectiveness of an ensemble Kalman filter based on the weather research and forecasting model to assimilate Doppler-radar radial-velocity observations for convection-permitting prediction of convection evolution in a high-impact heavy-rainfall event over coastal areas of South china during the pre-summer rainy season. An ensemble of 40 deterministic forecast experiments(40 DADF) with data assimilation(DA) is conducted, in which the DA starts at the same time but lasts for different time spans(up to 2 h) and with different time intervals of 6, 12, 24, and 30 min. The reference experiment is conducted without DA(NODA).To show more clearly the impact of radar DA on mesoscale convective system(McS)forecasts, two sets of 60-member ensemble experiments(NODA EF and exp37 EF) are performed using the same 60-member perturbed-ensemble initial fields but with the radar DA being conducted every 6 min in the exp37 EF experiments from 0200 to0400 BST. It is found that the DA experiments generally improve the convection prediction. The 40 DADF experiments can forecast a heavy-rain-producing McS over land and an McS over the ocean with high probability, despite slight displacement errors. The exp37 EF improves the probability forecast of inland and offshore McSs more than does NODA EF. compared with the experiments using the longer DA time intervals, assimilating the radial-velocity observations at 6-min intervals tends to produce better forecasts. The experiment with the longest DA time span and shortest time interval shows the best ***, a shorter DA time interval(e.g., 12 min) or a longer DA time span does not always help. The experiment with the shortest DA time interval and maximum DA window shows the best performance, as it corrects errors in the simulated convection evolution over both the inland and offshore areas. An improved representation of the initial state leads to dynamic and thermodynamic conditions that are more conducive to

关键词： Radial velocity EnKF Heavy rainfall forecast Pre-summer rainy season South china

cONTROLLING THE SURFAcE cOMPOSITION OF PcBM IN P3HT/PcBM BLEND FILMS BY USING MIXED SOLVENTS WITH DIFFERENT EVAPORATION RATES

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chinese Journal of Polymer Science 2013年第7期31卷 1029-1037页

作者： yue sun Jian-gang Liu Yan Ding 韩艳春 State Key Laboratory of Polymer Physics and chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences Graduate School of the chinese Academy of Sciences

The surface composition of poly（3-hexylthiophene-2,5-diyl） and fullerene derivative [6,6]-phenyl-c61-butyric acid methyl ester （P3HT/PcBM） blend films could be changed by controlling the film formation process via using mixed solvents with different evaporation rates. The second solvent, with a higher boiling point than that of the first solvent and much better solubility for PcBM than P3HT, is chosen to mix with the first solvent with a lower boiling point and good solubility for both PcBM and P3HT. The slow evaporation rate of the second solvent provides enough time for PcBM to diffuse upwards during the solvent evaporation. Thus, the weight ratio of PcBM and P3HT （mpcBM/mp3HT） at surface of the blend films was varied from ca. 0.1 to ca. 0.72, i.e., it increases about seven times by changing from single solvent to mixed solvents. Meanwhile, the mixed solvents were in favor to form P3HT naonofiber network and enhance phase separation of P3HT/PcBM blend films. As a result, the power conversion efficiency of the device from mixed solvents with slow evaporation process was about 1.5 times of the one from single solvents.

关键词： P3HT PcBM Surface composition Mixed solvents Slow evaporation.

A genetic algorithm based entity resolution approach with active learning

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Frontiers of computer Science 2017年第1期11卷 147-159页

作者： chenchen sun Derong SHEN yue KOU Tiezheng NIE Ge YU Sohool of Information Science and Engineering Northeastern University Shenyang 110819 China

Entity resolution is a key aspect in data quality and data integration, identifying which records correspond to the same real world entity in data sources. Many existing ap- proaches require manually designed match rules to solve the problem, which always needs domain knowledge and is time consuming. We propose a novel genetic algorithm based en- tity resolution approach via active learning. It is able to learn effective match rules by logically combining several different attributes＇ comparisons with proper thresholds. We use ac- tive learning to reduce manually labeled data and speed up the learning process. The extensive evaluation shows that the proposed approach outperforms the sate-of-the-art entity res- olution approaches in accuracy.

关键词： entity resolution genetic algorithm active learning data quality data integration

centimeter‑level‑precision seafloor geodetic positioning model with self‑structured empirical sound speed profile

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Satellite Navigation 2023年第3期4卷 35-53页

作者： Shuqiang Xue Baojin Li Zhen Xiao yue sun Jingsen Li chinese Academy of Surveying and Mapping Beijing 100830China School of civil and Architectural Engineering Shandong University of TechnologyZibo 255049China college of Geodesy and Geomatics Shandong University of Science and TechnologyQingdao 266510China

In-field Sound Speed Profile(SSP)measurement is still indispensable for achieving centimeter-level-precision Global Navigation Satellite System(GNSS)-Acoustic(GNSS-A)positioning in current state of the ***,in-field SSP measurement on the one hand causes a huge cost and on the other hand prevents GNSS-A from global seafloor geodesy especially for real-time *** propose an Empirical Sound Speed Profile(ESSP)model with three unknown temperature parameters jointly estimated with the seafloor geodetic station coordinates,which is called the 1st-level ***,regarding the sound speed variations of ESSP we propose a so-called 2nd-level optimization to achieve the centimeter-level-precision positioning for monitoring the seafloor tectonic ***-term seafloor geodetic data analysis shows that,the proposed two-level optimization approach can achieve almost the same positioning result with that based on the in-field *** influence of substituting the in-field SSP with ESSP on the horizontal coordinates is less than 3 mm,while that on the vertical coordinate is only 2–3 cm in the standard deviation sense.

关键词： GNSS-A Seafloor geodetic positioning Sound speed SSP Inversion

Pd(I)-catalyzed ring-opening arylation of cyclopropyl-α-aminoamides:Access toα-ketoamide peptidomimetics

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chinese chemical Letters 2024年第6期35卷 320-326页

作者： yue sun Liming Yang Yaohang cheng Guanghui An Guangming Li School of chemistry and Materials Science Heilongjiang UniversityHarbin 150080China

We report the unprecedent Pd(I)catalyzed ring-opening arylation of cyclopropyl-α-*** protocol allows facile access to biologically important α-ketoamide-containing oligopeptides and even more challenging peptide-natural product *** selectivity was achieved by introduction of special unnatural amino acids,which also meets the requisite of bioorthogonal *** investigations reveals a distinct domino radical ring-opening process through Pd(I)catalysis.

关键词： Pd(I)catalysis Ring-opening arylation Domino reactions Oligopeptides Late-stage functionalization

Tailoring two-dimensional surfaces with pillararenes based host-guest chemistry

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chinese chemical Letters 2020年第12期31卷 3095-3101页

作者： Run-Hao Li Junkai Ma yue sun Haibing Li Hubei Key Laboratory of catalysis and Materials Science College of Chemistry and Material SciencesSouth-Central University for NationalitiesWuhan 430074China Hubei Key Laboratory of Wudang Local chinese Medicine Research Department of ChemistrySchool ofPhannacyHubei University of MedicineShiyan 442000China Key Laboratory of Pesticide and chemical Biology(ccNU) Ministry of EducationCollege of ChemistryCentral China Normal UniversityWuhan 430079China

The two-dimensional surfaces have been fueled by the infinite possibility they offe red fo r basic re search,and for novel technologies in *** realize many of these promises,the effective strategies were to design and control their surface chemistry,which plays a vital role in determining the chemical and physical *** host-guest chemistry with the reversible noncovalent interactions between macrocyclic hosts and suitable guests can be readily used for constructing multifunctional *** pillararenes,possessed the unique structure,have attracted the attentions of researchers in recent *** feature article covers the recent development of pillararene-based twodimensional inte rfaces,including the fabrication and function of the hybrid *** combination of pillararenes and materials platform exhibited the novel property because of the characte ristic of cavity of macrocyclic host and confined spaces of *** anticipate that this review will be helpful to the researchers working in the fields of supramolecular chemistry and materials science.

关键词： Pillararenes Host-guest chemistry Two-dimensional surfaces

Unravelling crystal Structures of covalent Organi Frameworks by Electron Diffraction Tomography

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chinese Journal of chemistry 2020年第10期38卷 1153-1166页

作者： Tu sun Wei Lei Yanhang Ma yue-Biao Zhang School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

Featuring the art of covalent chemistry on 2D and 3D with molecular precision,covalent organic frameworks(cOFs)have attracted immense interests from inorganic,organic,polymer,materials and energy ***,due to the synthetic challenge of"crystallization problem",structural determination of cOFs has been the bottle-neck in speeding up their discovery and design,as well as building up their structureproperty *** diffraction tomography(EDT)has been developed to determine crystal structures of cOFs with only sub-micrometer sized single crystals,which enabled the ob initio determination of crystal structure,molecular connectivity,pore metrics,and host-guest interaction at the atomic *** this review,w e summarized the recent developments of EDT for addressing challenges in structure determinations of such e-beam sensitive,organic porous crystals,covering comprehensively automatic data collection,low dose,cryogenic protocols,structural solution method,powder X-ray diffraction refinement,and high-resolution transmission electron microscopy(HRTEM)imaging *** do believe the EDT will propel this field into the new era of cOF chemistry with atomic precision,and we envision the wide application of artificial intelligence will promote the structural determination and particle analysis of cOFs and related materials。

关键词： Electron valent refinement

Identification and biosynthesis of plant papanridins,a group of novel oligomeric flavonoids

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Molecular Plant 2023年第11期16卷 1773-1793页

作者： yue Zhu Seyit Yuzuak Xiaoyan sun De-Yu Xie Department of Plant and Microbial Biology North Carolina State UniversityRaleighNCUSA Department of chemistry North Carolina State UniversityRaleighNCUSA Department of Molecular Biology&Genetics Mehmet Akif Ersoy UniversityBurdurTurkey

The discovery of novel flavonoids and elucidation of their biosynthesis are fundamental to understanding their roles in plants and their benefits for human and animal ***,we report a new pathway for polymerization of a group of novel oligomeric flavonoids in *** engineered red cells for discovering genes of interest involved in the flavonoid pathway and identified a gene encoding a novel flavanol polymerase(FP)localized in the central *** catalyzes the polymerization of flavanols,such as epicatechin and catechin,to produce yellowish dimers or *** elucidation shows that these compounds feature a novel oligomeric flaven–flavan(FF)skeleton linked by interflavan–flaven and interflaven bonds,distinguishing them from proanthocyanidins and *** chemical and physical characterizations further confirmed the novel FFs as *** investigations demonstrated that FP polymerizes flavan-3-ols and flav-2-en-3-ol carbocation,forming dimeric or oligomeric flaven-4→8-flavans,which we term“papanridins.”Data from transgenic experiments,mutant analysis,metabolic profiling,and phylogenetic analyses show that the biosynthesis of papanridins is prevalent in cacao,grape,blueberry,corn,rice,Arabidopsis,and other species in the plant *** summary,our study discoveries a group of novel oligomeric flavonoids,namely papanridins,and reveals that a novel FP-mediated polymerization mechanism for the biosynthesis of papanridins in plants.

关键词： flavanol polymerase papanridin flavan-3-ol flav-2-en-3-ol flavan- flaven