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Exploring the effect of aggregation-induced emission on the excited state intramolecular proton transfer for a bis-imine derivative by quantum mechanics and our own n-layered integrated molecular orbital and molecular mechanics calculations

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Chinese Physics B 2019年第1期28卷 645-649页

作者： Huifang Zhao Chaofan Sun Xiaochun Liu Hang yin ying Shi Institute of Atomic and Molecular Physics Jilin University

We theoretically investigate the excited state intramolecular proton transfer(ESIPT) behavior of the novel fluorophore bis-imine derivative molecule HNP which was designed based on the intersection of 1-(hydrazonomethyl)-naphthalene-2-ol and 1-pyrenecarboxaldehyde. Especially, the density functional theory(DFT) and time-dependent density functional theory(TDDFT) methods for HNP monomer are introduced. Moreover, the "our own n-layered integrated molecular orbital and molecular mechanics"(ONIOM) method(TDDFT:universal force field(UFF)) is used to reveal the aggregation-induced emission(AIE) effect on the ESIPT process for HNP in crystal. Our results confirm that the ESIPT process happens upon the photoexcitation for the HNP monomer and HNP in crystal, which is distinctly monitored by the optimized geometric structures and the potential energy curves. In addition, the results of potential energy curves reveal that the ESIPT process in HNP will be promoted by the AIE effect. Furthermore, the highest occupied molecular orbital(HOMO) and lowest unoccupied molecular orbital(LUMO) for the HNP monomer and HNP in crystal have been calculated. The calculation demonstrates that the electron density decrease of proton donor caused by excitation promotes the ESIPT process. In addition, we find that the variation of atomic dipole moment corrected Hirshfeld population(ADCH) charge for proton acceptor induced by the AIE effect facilitates the ESIPT process. The results will be expected to deepen the understanding of ESIPT dynamics for luminophore under the AIE effect and provide insight into future design of high-efficient AIE compounds.

关键词： time-dependent density functional theory(TDDFT) method excited state intramolecular proton transfer(ESIPT) our own n-layered integrated molecular orbital and molecular mechanics(ONIOM) method potential energy curves atomic dipole moment corrected Hirshfeld population(ADCH) charge

Using MALDI-TOF MS coupled with a high-mass detector to directly analyze intact proteins in thyroid tissues

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Science China Chemistry 2018年第7期61卷 871-878页

作者： Shan-Shan Wang Yun-Jun Wang Jing Zhang Jun Xiang Tuan-Qi Sun yin-Long Guo State Key Laboratory of Organometallic Chemistry and National Center for Organic Mass Spectrometry in Shanghai Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences Department of Head and Neck Surgery Fudan University Shanghai Cancer Center Department of Oncology Shanghai Medical College Fudan University

Protein analysis is vital for biological and clinical research, but the measurement of unseparated, intact and high-mass proteins is also a challenging task by mass spectrometry-based methods. Here, we present a protocol for rapid and high-throughput analysis of intact proteins in tissue samples using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry（MALDITOF MS） combined with a high-mass detector platform. The method involves tissue specimens that undergo a simple protein extraction before MALDI-MS analysis. Using this method, the high abundance proteins in human thyroid carcinoma and paracarcinoma tissues were successfully investigated, and the mass spectra of the tissues of the 30 illustrated thyroid cancers showed remarkable differences. The peak intensity revealed a significant increase in human albumin in thyroid carcinoma tissues（p＆lt;0.05）. To validate the feasibility and credibility of this method, label-free proteomics quantitative analysis and Western blotting were used to relatively quantify the proteins in these tissues. Those results demonstrated a nearly 3-fold difference in human albumin levels between thyroid carcinoma and para-carcinoma tissues, which were consistent with the results of our method. The advantages of our method are easy sample handling, remarkable reproducibility and the ability to analyze high-mass proteins without digestion, which make them have the potential to be used in biological research and in clinical practice.

关键词： matrix-assisted laser desorption ionization time of flight mass spectrometry intact proteins analysis thyroid carcinoma high-mass detector

3D graphical visualization of the genetic architectures underlying complex traits in multiple environments

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 563-567页

作者： HU Cheng-cheng YE Xiu-zi ZHANG yin YU Rong-dong YANG Jian ZHU Jun College of Computer Science Zhejiang University Hangzhou 310027 China James D. Watson Institute of Genomic Science Zhejiang University Hangzhou 310029 China Institute of Bioinformatics. Zheiiane University. Hangzhou 310029. China

An approach for generating interactive 3D graphical visualization of the genetic architectures of complex traits in multiple environments is described. 3D graphical visualization is utilized for making improvements on traditional plots in quan- titative trait locus (QTL) mapping analysis. Interactive 3D graphical visualization for abstract expression of QTL, epistasis and their environmental interactions for experimental populations was developed in framework of user-friendly software QTLNetwork (http://***/software/qtlnetwork). Novel definition of graphical meta system and computation of virtual coordinates are used to achieve explicit but meaningful visualization. Interactive 3D graphical visualization for QTL analysis provides geneticists and breeders a powerful and easy-to-use tool to analyze and publish their research results.

关键词： Ouantitative trait locus (QTL) Visualization 3D graphical Interactive visualization

OES diagnostic of radicals in 33MHz radio-frequency Ar/C_2H_5OH atmospheric pressure plasma jet

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Plasma Science and Technology 2019年第2期21卷 52-59页

作者： Qianghua YUAN Pei REN Yongjie ZHOU Guiqin yin Chenzhong DONG Key Laboratory of Atomic and Molecular Physics & Functional Materials of Gansu province College of Physics and Electronic EngineeringNorthwest Normal University

Ar/C_2H_5OH plasma jet is generated at atmospheric pressure by 33 MHz radio-frequency power source. This RF excitation frequencies which are higher than 13.56 MHz had rarely been used in atmospheric pressure plasma. The plasma characteristics of ethanol are investigated. The introduction of ethanol leads to the generation of four excited carbonaceous species C, CN, CH and C_2 in plasma, respectively. Optical emission intensities of four carbonaceous species were strengthened with ethanol content increasing in the range of 0-4600 ppm. The ethanol content increase results in all the Ar spectra lines decrease. The reason is that the electron temperature decreases when ethanol content is high. The emission intensity ratios of C/C_2, CN/C_2 and CH/C_2 decrease with the increase of ethanol content, showing that the relative amount of C_2 is increasing by increasing the ethanol flow. The emission intensity ratios of excited species did not change much with the increase of RF power in stable discharge mode.

关键词： atmospheric pressure plasma optical emission spectroscopy radical analysis

Automatic Video Segmentation Based on Information Centroid and Optimized SaliencyCut

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Journal of Computer Science & Technology 2020年第3期35卷 564-575页

作者： Hui-Si Wu Meng-Shu Liu Lu-Lu yin Ping Li Zhen-Kun Wen Hon-Cheng Wong College of Computer Science and Software Engineering Shenzhen UniversityShenzhen 518060China Department of Computing The Hong Kong Polytechnic UniversityHong Kong 999077China Faculty of Information Technology Macao University of Science and TechnologyMacao 999078China

We propose an automatic video segmentation method based on an optimized SaliencyCut equipped with information centroid(IC)detection according to level balance principle in physical *** the existing methods,the image information of another dimension is provided by the IC to enhance the video segmentation ***,our IC is implemented based on the information-level balance principle in the image,and denoted as the information pivot by aggregating all the image information to a *** effectively enhance the saliency value of the target object and suppress the background area,we also combine the color and the coordinate information of the image in calculating the local IC and the global IC in the *** saliency maps for all frames in the video are calculated based on the detected *** applying IC smoothing to enhance the optimized saliency detection,we can further correct the unsatisfied saliency maps,where sharp variations of colors or motions may exist in complex ***,we obtain the segmentation results based on IC-based saliency maps and optimized *** method is evaluated on the DAVIS dataset,consisting of different kinds of challenging *** with the state-of-the-art methods are also conducted to evaluate our *** visual results and statistical comparisons demonstrate its advantages and robustness for automatic video segmentation.

关键词： automatic video segmentation information centroid saliency detection optimized SaliencyCut

Synthesis and Crystal Structure of a New cis-Dioxovanadium (V) Complex with Pyruvic Acid Isonicotinyl Hydrazone (PAINH)

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Chinese Journal of Structural Chemistry 2006年第2期25卷 219-223页

作者： CHEN Rui-Jin ZHOU yin-Zhuang HU Dai-Di TU Shu-Jie XIAO Ling-Mei DePartment of Chemistry Capital Normal University Beijing 100037 China

A new cis-dioxovanadium （V） complex [VO2（C9H8N3O3）]（C5H5N） involving a carboxyl group coordination employing a tridentate Schiff Base derived from pyruvic acid and isonicotinyl hydrazide is reported. This complex crystallizes in triclinic, space group P1^- with a = 7.3522 （12）, b = 7.8376（13）, c = 14.898（2） ,A°, a = 84.010（2）, β = 86.568（2）, γ= 64.586（2）°, V = 771.1（2）A °^3 ,Z = 2, F（000） = 376, Mr = 368.22, D, = 1.586 g/cm^3, g = 0.677 mm ^-1, R = 0.0421 and wR = 0.1253. The vanadium atom of the dioxovanadium （V） is five-coordinated to furnish a distorted trigonal bipyramid geometry.

关键词： dioxovanadium complex pyruvic acid isonicotinyl hydrazone (PAINH),crystal structure

Ultra-light, high flexible and efficient CNTs/Ti3C2-sodium alginate foam for electromagnetic absorption application

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Journal of Materials Science & Technology 2019年第12期35卷 2859-2867页

作者： Xingmin Liu Nan Chai Zhaoju Yu Hailong Xu Xinliang Li Jiquan Liu Xiaowei yin Ralf Riedel College of Materials Key Laboratory of High Performance Ceramic Fibers(Xiamen University)Ministry of EducationXiamen361005China Institutfiir Materialwissenschaft Technische Universitdt DarmstadtD-64287DarmstadtGermany College of Materials Fujian Key Laboratory of Advanced MaterialsXiamen UniversityXiamen361005China Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi'an710072China Technische Universitat Darmstadt Eduard-Zintl-lnstitutfur Anorganische und Physikalische ChemieAlarich-Weiss-Straβe 4.D-64287DarmstadtGermany

Ultra-light carboxylic functionalized multi-walled carbon nanotubes(CNTs-COOH) and Ti3C2 MXene hybrids modified sodium alginate(CNTs/Ti3C2-SA) based composite foams were prepared through ice-templated freeze-drying method. The microstructure of the synthesized CNTs/Ti3C2 hybrids and CNTs/Ti3C2-SA foams is characterized by the presence of CNTs inserted between MXene layers which prevents their restacking. The resultant CNTs/Ti3C2 hybrids exhibit a unique sandwich-like hierarchical structure. Scanning electron microscopy(SEM) images show that the CNTs/Ti3C2-SA foam exhibits a heterogeneous anisotropic microstructure and CNTs/Ti3C2 hybrids are homogeneously dispersed in the skeleton of the porous foam. In case that the content of the hybrids amounts 40 mg/cm^3, the CNTs/Ti3C2-SA foam possesses excellent electromagnetic(EM) absorption performance with a minimum reflection coefficient(RCmin) as low as-40.0 dB. In case of a sample thickness of 3.95 mm, the RCminreaches-24.4 dB and the effective absorption bandwidth covers the whole X band from 8.2 to 12.4 GHz. A control test shows that, with the same absorbent content, the CNTs/Ti3C2-SA foam exhibits a far better EM performance than that of CNT-free Ti3C2-SA foam.

关键词： Carbon nanotubes MXene Sodium alginate Electromagnetic absorption properties

Impact of atmospheric circulations on droughts and drought propagation over China

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Science China Earth Sciences 2024年第8期67卷 2633-2648页

作者： Ziye GU Lei GU Jiabo yin Wei FANG Lihua XIONG Jun GUO Ziyue ZENG Jun XIA School of Civil and Hydraulic Engineering Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Water Resources Engineering and Management Wuhan 430072China Changjiang River Scientific Research Institute Wuhan 430010China

The GRACE satellite mission provides a new approach for monitoring,tracking,and assessing drought conditions by detecting changes in Earth's gravitational fields and inversing signals of terrestrial water storage *** studies of terrestrial water storage anomalies related droughts paid rare attention to the behind atmospheric physical mechanisms,nor quantified the risk propagation patterns between terrestrial water storage deficits and hydrological or agricultural *** this study,we first extract terrestrial water storage(TWS) droughts,hydrological droughts,and agricultural droughts by using multiple variables including TWS from the GRACE/GRACE-FO satellites,runoff and soil moisture from the ERA5-Land reanalysis *** then identify key atmospheric and oceanic oscillation indices affecting water deficits by employing machine learning *** characterize the joint distributions between drought duration and severity by using the Copula function and quantify the risk propagation of hydrological and agricultural droughts to TWS *** results show that:(1) From 2002 to 2021,there is a significant decrasing trend of TWS in China;the WPIO group atmospheric circulation indices(sea surface temperature index within the Western Pacific and Indian Ocean) contributes the most to ***,the sea surface temperature anomalies within the NINO 3.4 region as well as the Western Pacific Warm Pool area index show significantly positive correlation relationships with TWS in southern China;(2) The northwestern China,the Yangtze River basin,and the downstream of the Pearl River basin are the hotspots of TWS ***,the hotspots of hydrological droughts locate in northwestern China and the hotspots of agricultural droughts locate in South China and eastern Tibetan Plateau;(3) The elastic coefficients of hydrological droughts propagating to TWS droughts are higher than those of agricultural droughts,indicating that the TWS droughts

关键词： GRACE satellites Drought Drought propagation Atmospheric circulation Copula function

Tunable polarization-drived superior energy storage performance in PbZrO_(3) thin films

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Journal of Advanced Ceramics 2023年第5期12卷 930-942页

作者： Tiandong Zhang Zhuangzhuang Shi Chao yin Changhai Zhang Yue Zhang Yongquan Zhang Qingguo Chen Qingguo Chi Key Laboratory of Engineering Dielectrics and Its Application Ministry of EducationHarbin University of Science and TechnologyHarbin 150080China Department of Materials Science and Engineering Korea Advanced Institute of Science and TechnologyDaejeon 305-701Republic of Korea

Antiferroelectric PbZrO_(3)(AFE PZO)films have great potential to be used as the energy storage dielectrics due to the unique electric field(E)-induced phase transition ***,the phase transition process always accompanies a polarization(P)hysteresis effect that induces the large energy loss(Wloss)and lowers the breakdown strength(EBDS),leading to the inferior energy storage density(Wrec)as well as low *** this work,the synergistic strategies by doping smaller ions of Li^(+)–Al^(3+)to substitute Pb2+and lowering the annealing temperature(T)from 700 to 550℃are proposed to change the microstructures and tune the polarization characters of PZO films,except to dramatically improve the energy storage *** prepared Pb_((1−x))(Li_(0.5)Al_(0.5))_(x)ZrO_(3)(P_((1−x))(L_(0.5)A_(0.5))_(x)ZO)films exhibit ferroelectric(FE)-like rather than AFE character once the doping content of Li^(+)–Al^(3+)ions reaches 6 mol%,accompanying a significant improvement of W_(rec) of 49.09 J/cm^(3),but the energy storage efficiency(η)is only 47.94%due to the long-correlation of FE ***,the low-temperature annealing is carried out to reduce the crystalline degree and the P loss.P_(0.94)(L_(0.5)A_(0.5))_(0.06)ZO films annealed at 550℃deliver a linear-like polarization behavior rather than FE-like behavior annealed at 700℃,and the lowered remanent polarization(P_(r))as well as improved E_(BDS)(4814 kV/cm)results in the superior Wrec of 58.7 J/cm^(3) and efficiency of 79.16%,simultaneously possessing excellent frequency and temperature stability and good electric fatigue tolerance.

关键词： lead zirconate ionic pair polarization breakdown strength energy storage