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Design high-performance narrowband emitters for blue light-emitting diodes through manipulating resonance structure of aromatic heterocycles

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Science China Chemistry 2025年

作者： Yue Yu Lei Xu Wenle Tan Yuyu pan Jiyin Xiao Bohan Wang Guangjun Tian Yuguang Ma Lei Ying Institute of Polymer Optoelectronic Materials and Devices Guangdong Basic Research Center of Excellence for Energy and Information Polymer Materials State Key Laboratory of Luminescent Materials and Devices South China University of Technology School of Petrochemical Engineering Shenyang University of Technology Key Laboratory for Microstructural Material Physics of Hebei Province School of Science Yanshan University

Narrowband light-emitting materials play critical roles in improving the color gamut and energy consumption of electroluminescence. Herein we demonstrated that by regulating the ground state resonance structure form of emitters with polycyclic aromatic heterocycles, the high-energy vibration of the C–C bond can be effectively suppressed, resulting in narrow emission like classical cyanine dyes. The designed compounds consist of twist and planar conformation, while having differences in the orientation of the positioning electron-donating(nitrogen) and electron-accepting(carbonyl) groups in the polycyclic aromatic hydrocarbon skeleton. The resulting compound Ac-Ph-Ac with a dominated zwitterionic resonance structure exhibits a relatively wide electroluminescent profile with the full width at half maximum(FWHM) of 42 nm and moderate device performance. In contrast, the “soliton transition” of 2AcPh based on the cyanine limit character effectively suppresses C–C stretching vibration in the polycyclic aromatic heterocycle skeleton, leading to a narrow electroluminescent profile with FWHM of 30 nm(0.16 eV)associated with an impressively high external quantum efficiency of 28.52%, which is among the highest efficiencies of so far reported non-sensitized organic light-emitting diodes.

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Research on cubic polynomial acceleration and deceleration control model for high speed NC machining

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第3期9卷 358-365页

作者： hong-bin LENG Yi-jie WU Xiao-hong pan Institute of Modern Manufacture Engineering Zhejiang University Hangzhou 310027 China

To satisfy the need of high speed NC (numerical control) machining, an acceleration and deceleration (acc/dec) control model is proposed, and the speed curve is also constructed by the cubic polynomial. The proposed control model provides continuity of acceleration, which avoids the intense vibration in high speed NC machining. Based on the discrete characteristic of the data sampling interpolation, the acc/dec control discrete mathematical model is also set up and the discrete expression of the theoretical deceleration length is obtained furthermore. Aiming at the question of hardly predetermining the deceleration point in acc/dec control before interpolation, the adaptive acc/dec control algorithm is deduced from the expressions of the theoretical deceleration length. The experimental result proves that the acc/dec control model has the characteristic of easy implementation, stable movement and low impact. The model has been applied in multi-axes high speed micro fabrication machining successfully.

关键词： High speed NC machining Acceleration and deceleration (acc/dec) control model Cubic speed curve Discrete mathematical model Adaptive acceleration and deceleration control algorithm

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Understanding visual-auditory correlation from heterogeneous features for cross-media retrieval

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 241-249页

作者： hong ZHANG Yan-yun WANG hong pan Fei WU College of Computer Science and Technology Wuhan University of Science and Technology Wuhan 430081 China School of Computer Science and Technology Zhejiang University Hangzhou 310027 China School of Elementary Education Hangzhou Normal University Hangzhou 310036 China School of Information Engineering Hangzhou Normal University Hangzhou 310036 China

Cross-media retrieval is an interesting research topic,which seeks to remove the barriers among different *** enable cross-media retrieval,it is needed to find the correlation measures between heterogeneous low-level features and to judge the semantic *** paper presents a novel approach to learn cross-media correlation between visual features and auditory features for image-audio retrieval.A semi-supervised correlation preserving mapping(SSCPM)method is described to construct the isomorphic SSCPM subspace where canonical correlations between the original visual and auditory features are further *** optimization algorithm is proposed to improve the local image cluster and audio cluster quality in an interactive way.A unique relevance feedback strategy is developed to update the knowledge of cross-media correlation by learning from user behaviors,so retrieval performance is enhanced in a progressive *** results show that the performance of our approach is effective.

关键词： Heterogeneity Cross-media retrieval Subspace optimization Dynamic correlation update

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Electrocatalytic Oxidation of Calcium Folinate on Carboxyl Graphene Modified CuxO/Cu Electrode

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Chinese Journal of Chemical Physics 2016年第6期29卷 729-734,I0002页

作者： Li-wen Wang Shou-guo Wu Tian-yang Shi wei wei pan pan Departmentol:Chemistry UniversityofScienceandTechnologyofChinaHefei230026China

Carboxyl graphene modified CuxO/Cu electrode was fabricated. The bare copper electrode was firstly anodic polarized in 1.0 mol/L NaOH solution in order to get CuxO nanoparticles, then the carboxyl graphene （CG） was electrodeposited on the CuxO/Cu electrode by cyclic potential sweeping. The electrocatalytic oxidation behaviors of calcium folinate （CF） at the graphene modified CuxO/Cu electrode were investigated by cyclic voltammetry. A positive scan polarization reverse catalytic voltammetry was used to obtain the pure catalytic oxidation current. The graphene modified CuxO/Cu electrode was served as the electrochemical sensor of CF, a highly sensitivity of 22.0μA.（μmol/μL）^-1cm^-2 was achieved, and the current response was linear with increasing CF concentration in the range of 2.0×10^-7 mol/L to 2.0×10^-5 mol/L, which crossed three orders of magnitude, and the detection limit was found 7.6×10^-5 mol/L （S/N=3）. In addition, the proposed sensor was successfully applied in determination of CF in drug sample.

关键词： Calcium folinate Carboxyl graphene CuxO/Cu electrode Chemically modi-fied electrode Positive scan polarization reverse catalytic voltammetry

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Cost Sensitive Multi-Granulation Preference Relation Rough Set for Ordinal Decision System

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Journal of Electronic Science and Technology 2017年第3期15卷 289-302页

作者： wei pan Kun She Computer School China West Normal University Nanchong 637009 School of Information and Software Engineering University of Electronic Science and Technology of China Chengdu 611731

The preference analysis is a class of important issues in multi-criteria ordinal decision *** rough set is an effective approach to handle preference *** order to solve the multi-criteria preference analysis problems,this paper improves the preference relation rough set model and expands it to multi-granulation *** is also an important issue in the field of decision *** the cost into consideration,we also expand the model to the cost sensitive multi-granulation preference relation rough *** theorems are represented,and the granule structure selection based on approximation quality is *** experimental results show that the multi-granulation preference rough set approach with the consideration of cost has a better performance in granule structure selection than that without cost consideration.

关键词： Index Terms-Cost multi-granulation rough set,preference relation rough set

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Copper Promoted Au/ZnO-CuO Catalysts for Low Temperature Water-gas Shift Reaction

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Chemical Research in Chinese Universities 2006年第1期22卷 99-102页

作者： LIAN hong-lei JIA Ming-jun pan wei-cheng ZHANG Wen-xiang JIANG Da-zhen College of Chemistry Jilin University Changchun 130023 P. R. China School of Chemical Engineering Zhengzhou University Zhengzhou 450002 P. R. China

Various copper promoted Au/ZnO-CuO catalysts with different atomic ratios of Cu to Zn prepared by means of co-precipitation were tested for the low temperature water-gas shift（WGS） reaction. The catalytic activity of the catalyst depends largely on the ratio of Cu to Zn. The addition of an appropriate amount of copper can considerably improve both the catalytic activity and the stability of the catalyst in comparison with those of copper-free Au/ZnO cata- lysts. The enhanced reducibility of copper oxide in the Au/ZnO-CuO ternary-component catalysts, which was confirmed by H2-TPR, may be related to the high activity and stability of the catalyst for the low temperature WGS reaction.

关键词： Water-gas shift reaction ZnO CuO Gold

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A de novo transcriptomic analysis to reveal functional genes in Apolygus lucorum

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Insect Science 2016年第1期23卷 2-14页

作者： De-pan Cao Yang Liu Jin-Jin wei Jian-hong Li Gui-Rong Wang State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing Laboratory of Pesticide College of Plant Science & Technology Huazhong Agricultural University Wuhan China

The widespread planting of genetically engineered cotton producing the CrylAc toxin has led to significantly reduced pesticide applications since 1997. However, conse- quently, the number of green mirid bugs （GMB）, Apolygus lucorum （Meyer-Diir） has in- creased. So far the GMB, instead of the cotton bollworm Helicoverpa armigera （Hiibner）, has become the major pest in the transgenic Bt cotton field and has influenced cotton yield. Disproportionately, only a few studies on GMB at molecular level have been re- ported. Libraries from both third instar nymphs and adults were sequenced using Illumina technology, producing more than 106 million short reads and assembled into 63 029 uni- genes of mean length 597 nt and N50 813 nt, ranging from 300 nt to 9771 nt. BLASTx analysis against Nr, Swissprot, GO and COG was performed to annotate these unigenes. As a result, 26 478 unigenes （42.01%） matched to known proteins and 107 immune-related, 320 digestive-related and 53 metamorphosis-related genes were detected in these annotated unigenes. Additionally, we profiled gene expression using mapping based differentially expressed genes （DEGs） strategy between the two developmental stages： nymph and adult. The results demonstrated that thousands of genes were significantly differentially ex- pressed at different developmental stages. The transcriptome and gene expression data provided comprehensive and global gene resources of GMB. This transcriptome would improve our understanding of the molecular mechanisms of various underlying biological characteristics, including development, digestion and immunity in GMB. Therefore, these findings could help elucidate the intrinsic factors of the GMB resurgence, offering novel pest management targets for future transgenic cotton breeding.

关键词： Apolygus lucorum digestion immunity metamorphosis transcriptome

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Nondeterministic Probabilistic Petri Net -- A New Method to Study Qualitative and Quantitative Behaviors of System

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Journal of Computer Science & Technology 2013年第1期28卷 203-216页

作者： Yang Liu Huai-Kou Miao hong-wei Zeng Yan Ma pan Liu School of Computer Engineering and Science Shanghai University Shanghai 200072 China School of Information Science and Technology Taishan University Taian 271021 China State Key Laboratory of Novel Software Technology Nanjing University Nanjing 210093 China

There are many variants of Petri net at present, and some of them can be used to model system with both function and performance specification, such as stochastic Petri net, generalized stochastic Petri net and probabilistic Petri net. In this paper, we utilize extended Petri net to address the issue of modeling and verifying system with probability and nondeterminism besides function aspects. Using probabilistic Petri net as reference, we propose a new mixed model NPPN （Nondeterministic Probabilistic Petri Net） system, which can model and verify systems with qualitative and quantitative behaviours. Then we develop a kind of process algebra for NPPN system to interpret its algebraic semantics, and an action- based PCTL （Probabilistic Computation Tree Logic） to interpret its logical semantics. Afterwards we present the rules for compositional operation of NPPN system based on NPPN system process algebra, and the model checking algorithm based on the action-based PCTL. In order to put the NPPN system into practice, we develop a friendly and visual tool for modeling, analyzing, simulating, and verifying NPPN system using action-based PCTL. The usefulness and effectiveness of the NPPN system are illustrated by modeling and model checking an elaborate model of travel arrangements workflow.

关键词： nondeterminism probabilistic Petri net model checking action-based probabilistic computation tree logic

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Construction of Solutions and L^1-error Estimates of Viscous Methods for Scalar Conservation Laws with Boundary

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Acta Mathematica Sinica,English Series 2007年第3期23卷 393-410页

作者： hong Xia LIU Tao pan Department of Mathematics Jinan University Guangzhou 510632 P. R. China

This paper is concerned with an initial boundary value problem for strictly convex conservation laws whose weak entropy solution is in the piecewise smooth solution class consisting of finitely many discontinuities. By the structure of the weak entropy solution of the corresponding initial value problem and the boundary entropy condition developed by Bardos-Leroux Nedelec, we give a construction method to the weak entropy solution of the initial boundary value problem. Compared with the initial value problem, the weak entropy solution of the initial boundary value problem includes the following new interaction type： an expansion wave collides with the boundary and the boundary reflects a new shock wave which is tangent to the boundary. According to the structure and some global estimates of the weak entropy solution, we derive the global L^1-error estimate for viscous methods to this initial boundary value problem by using the matching travelling wave solutions method. If the inviscid solution includes the interaction that an expansion wave collides with the boundary and the boundary reflects a new shock wave which is tangent to the boundary, or the inviscid solution includes some shock wave which is tangent to the boundary, then the error of the viscosity solution to the inviscid solution is bounded by O（ε^1/2） in L^1-norm; otherwise, as in the initial value problem, the L^1-error bound is O（ε｜ In ε｜）.

关键词： scalar conservation laws initial boundary value problem global weak entropy solution,error estimate of viscous methods

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Pressure fluctuation signal analysis of pump based on ensemble empirical mode decomposition method

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Water Science and Engineering 2014年第2期7卷 227-235页

作者： hong pan Min-sheng BU College of Energy and Electrical Engineering Hohai University College of Mechanical and Electrical Engineering Hohai University

Pressure fluctuations, which are inevitable in the operation of pumps, have a strong non-stationary characteristic and contain a great deal of important information representing the operation conditions. With an axial-flow pump as an example, a new method for time-frequency analysis based on the ensemble empirical mode decomposition （EEMD） method is proposed for research on the characteristics of pressure fluctuations. First, the pressure fluctuation signals are preprocessed with the empirical mode decomposition （EMD） method, and intrinsic mode functions （IMFs） are extracted. Second, the EEMD method is used to extract more precise decomposition results, and the number of iterations is determined according to the number of IMFs produced by the EMD method. Third, correlation coefficients between IMFs produced by the EMD and EEMD methods and the original signal are calculated, and the most sensitive IMFs are chosen to analyze the frequency spectrum. Finally, the operation conditions of the pump are identified with the frequency features. The results show that, compared with the EMD method, the EEMD method can improve the time-frequency resolution and extract main vibration components from pressure fluctuation signals.

关键词： pressure fluctuation ensemble empirical mode decomposition intrinsic modefunction correlation coefficient

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