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Chinese Journal of Polymer Science 2023年第5期41卷 621-639,I0005页

作者： Bo-Han Wang Yu-guang ma Yong Cao Institute of Polymer Optoelectronic materials and Devices State Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhou 510640China

Electrodeposition is an old and effective method for the fabrication of organic *** electrodeposited organic films have been widely used in various applications,highly luminescent films have been a great challenge because the electrochemically doped state may strongly quench the *** the first part of this review,the organic electrodeposition techniques,along with general electropolymerization and other special electrodepositions are *** the second part of the review,we describe how to electrochemically fabricate luminescent films for organic light-emitting diodes(OLEDs).With the rational molecular design and well-controlled electrodeposition process,we have not only demonstrated high-performance OLEDs,but also paved a promising way to practice active-matrix OLEDs(AMOLEDs)and super-resolution *** particular,RGB 3×3 array OLEDs based on active-matrix substrates,RGB passive-matrix OLEDs(PMOLEDs)with a resolution of 210 ppi,and monochromatic OLEDs with a super-resolution of 2822 ppi have been successfully *** is highly anticipated that the organic electrodeposition technology is of comparable or perhaps even higher contenders in manufacturing and downscaling OLEDs and AMOLEDs with low-cost and high-resolution for the human-computer interaction fields such as augmented reality(AR),virtual reality(VR),etc.

关键词： Electrochemistry Organic electrodeposition Electropolymerization Luminescent films OLEDs

Pd（Ⅱ）-Catalyzed Phosphorylation of Enamido C（sp^2）-H Bonds： A General Route to β-Amido-vinylphosphonates

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Chinese Journal of Chemistry 2018年第9期36卷 809-814页

作者： Baokun qiao hao-qiang Cao Yin-Jun Huang Yue Zhang Jing Nie Fa-guang Zhang Jun-An ma Department of Chemistry Tianjin Key Laboratory of Molecular Optoelectronic Sciences and Tianjin Collaborative Innovation Center of Chemical Science & Engineering Tianjin University Tianjin 300072 China

Organophosphorus compounds are essential structures in modern pharmaceutical, agrochemical, and material sciences. The development of new and efficient methods for the synthesis of C-P bonds has been an important focus of research. We herein report a Pd-catalyzed enamido C（sp2）-H phosphorylation for direct construction of C-P bonds under simple and convenient conditions without the need for additional ligands or directing groups. The present reaction can tolerate a wide range of functional groups, and furnish a variety of phosphorylation products including tetrasubstituted-vinyl β-aminophosphonates that are otherwise difficult to access. This protocol was also exemplified into the late-stage modification of bioactive natural prod- ucts and was suitable for large-scale synthesis.

关键词： C-H activation phosphorylation palladium catalysis enamines late-stage functionalization

DELLA-GRF4-mediated coordination of growth and nitrogen metabolism paves the way for a new Green Revolution

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Science China(Life Sciences) 2018年第9期61卷 1130-1131页

作者： Kun ma Yao-guang Liu State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of Life Sciences South China Agricultural University

The Green Revolution （GR） based on semi-dwarf breeding has greatly increased cereal crop yields since the 1960＇*** to appropriate plant height, the semi-dwarf crop plants are beneficial to increase light utilization and improve the lodging-resistance, and eventually increase yield potential （Hedden, 2003）. During the past 50 years, the worldwide application of semi-dwarf crop breeding has produced plenty of elite varieties. The characters of Green Revolution varieties （GRVs） are caused by the mutant growth-repressing genes.

关键词：新陈代谢格林生长道路协作世界范围氮庄稼

露天矿区环境下GPS/INS组合导航算法研究

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大地测量与地球动力学 2025年第1期45卷 29-35页

作者：郝婷崔丽珍杜永兴马宝良内蒙古科技大学数智产业学院内蒙古自治区包头市014010

针对露天矿区道路窄、弯道多,沿途布满碎石、路面颠簸不平,导致运输车辆在定位时出现系统模型异常及量测噪声不确定性的问题,提出一种带有噪声估计器的SVD-AUKF算法。该算法通过对协方差矩阵进行奇异值分解,抑制滤波过程中出现的病态矩... 详细信息

针对露天矿区道路窄、弯道多,沿途布满碎石、路面颠簸不平,导致运输车辆在定位时出现系统模型异常及量测噪声不确定性的问题,提出一种带有噪声估计器的SVD-AUKF算法。该算法通过对协方差矩阵进行奇异值分解,抑制滤波过程中出现的病态矩阵,利用Sage-Husa估计器对量测噪声进行估计,减少系统状态误差,引入自适应因子实时修正系统模型误差以抑制滤波发散。将提出的SVD-AUKF算法应用于GPS/INS组合导航系统模型,并在矿山环境下进行车载实验,结果表明,新算法适用性好,相较AUKF算法,每个定位点在东、北、天方向上的位置精度分别提高50.69%、51.20%、48.54%,速度精度分别提高31.24%、33.83%、31.30%,能够有效改善滤波性能,提高系统定位精度。

关键词：无迹卡尔曼滤波 Sage-Husa估计器 SVD-AUKF 松组合露天矿区

Two-Stream Architecture as a Defense against Adversarial Example

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Journal of Electronic Science and Technology 2022年第1期20卷 81-91页

作者： hao Ge Xiao-guang Tu Mei Xie Zheng ma School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 610054 School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054

The performance of deep learning on many tasks has been ***,recent studies have shown that deep learning systems are vulnerable to small specifically crafted perturbations imperceptible to *** with such perturbations are called adversarial *** have been proven to be an indisputable threat to deep neural networks(DNNs)based applications,but DNNs have yet to be fully elucidated,consequently preventing the development of efficient defenses against adversarial *** study proposes a two-stream architecture to protect convolutional neural networks(CNNs)from attacks by adversarial *** model applies the idea of“two-stream”used in the security ***,it successfully defends different kinds of attack methods because of differences in“high-resolution”and“low-resolution”networks in feature *** study experimentally demonstrates that our two-stream architecture is difficult to be defeated with state-of-the-art *** two-stream architecture is also robust to adversarial examples built by currently known attacking algorithms.

关键词： Adversarial example deep learning neural network

Limiting Behaviors for Longest Consecutive Switches in anⅡD Bernoulli Sequence

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Acta mathematica Sinica,English Series 2023年第6期39卷 1138-1146页

作者： Chen Xu hao Ting ma College of mathematics Sichuan UniversityChengdu 610065P.R.China

In this paper we mainly discuss lower and upper bounds for the length of longest consecutive switches inⅡD Bernoulli *** work is an extension of results for longest consecutive switches in unbiased coin-tossing,and m... 详细信息

关键词： Longest consecutive switches lower and upper bounds Borel-Cantelli lemma

Hamilton-Souplet-Zhang's gradient estimates for two weighted nonlinear parabolic equations

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Applied mathematics(A Journal of Chinese Universities) 2017年第3期32卷 353-364页

作者： ma Bing-qing HUANG guang-yue Department of mathematics Henan Normal University Xinxiang 453007 China

In this paper, we consider gradient estimates for positive solutions to the following weighted nonlinear parabolic equations on a complete smooth metric measure space with only Bakry-Émery Ricci tensor bounded below: One is $${u_t} = {\Delta _f}u + au\log u + bu$$ with a, b two real constants, and another is $${u_t} = {\Delta _f}u + \lambda {u^\alpha }$$ with λ, α two real constants. We obtain local Hamilton-Souplet-Zhang type gradient estimates for the above two nonlinear parabolic equations. In particular, our estimates do not depend on any assumption on f.

关键词： Hamilton’s gradient estimate Souplet-Zhang’s gradient estimate weighted nonlinear parabolic equation Bakry-Émery Ricci tensor

Spatial-temporal dynamics of alpine grassland coverage and its response to climate warming in *** Nature Preserve during 2000-2019

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Journal of Mountain Science 2022年第8期19卷 2297-2311页

作者： ma Fei PENG Pei-hao College of Earth Sciences Chengdu University of TechnologyChengdu 610059China

The Qinghai-Tibet Plateau(QTP)has the largest and highest alpine grassland ecosystem in the world,which is considered to be the most sensitive and vulnerable ecosystem to climate *** dynamic changes and driving mechanism have always been widely *** Qomolangma National Nature Preserve(QNNP),with the largest altitude difference in the world,was selected as the study area to analyse the spatial-temporal dynamics of grassland coverage and the different characteristics of elevation gradients at the southern slope(SS)and northern slope(NS)with MODIS MOD13Q1 NDVI and MOD11A2 land surface temperature data from 2000to 2019 using the mann-Kendall trend test and Theil-Sen slope ***,the response mechanism of grassland coverage to climate warming is *** results revealed that from 2000 to 2019,the grassland coverage change in the study area is mainly *** increased area proportion of grassland coverage on the southern slope is significantly higher than that on the northern slope,and the decreased area proportion of grassland coverage on the northern slope is significantly greater than that on the southern *** change characteristics of grassland coverage in the QNNP exhibit an obvious elevation gradient;the higher the elevation,the greater the increased area proportion of grassland coverage,particularly on the *** land surface temperature can be used as a proxy for analysing the temporal and spatial variation trends of air temperature in the *** the increase of the altitude,the land surface temperature rise rate on both the southern slope and northern slope exhibited an increasing trend,and the sensitivity of grassland coverage to temperature rise was higher on the northern *** water condition was the decisive factor for the horizontal and vertical spatial heterogeneity of the dynamic change of grassland coverage,and the melting of glaciers and thawing of permafrost were important sources of water for grassland gro

关键词： Alpine grassland Global warming Vegetation dynamic Elevation gradient Qomolangma

How to Recognize Nonexpansive mappings and Isometric mappings

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Acta mathematica Sinica,English Series 2011年第10期27卷 1959-1966页

作者： guang Gui DING Yu Mei ma School of mathematical Sciences and LPMC Nankai University Tianjin 300071 P. R. China Department of Applied mathematics Dalian Nationality University Liaoning 116600 P. R. China

In two real Banach spaces, we shall present two conditions, under one of which each nonexpansive mapping must be an isometry.

关键词： Nonexpansive mapping smooth point weak*-compact set

Experimental investigation of unsteady attached cavitating flow induced pressure fluctuation

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Journal of Hydrodynamics 2022年第1期34卷 31-42页

作者： Hou-sheng Zhang guang-hao Chen Qin Wu Biao Huang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China AVIC Jincheng Nanjing Engineering Institute of Aircraft System Nanjing211106China

This paper experimentally investigates the pressure fluctuation induced by the unsteady attached cavitating flow, with special focus on the quasi-periodic cloud cavitation. A simultaneous sampling method is adopted for the synchronous measurement of the wall pressure signals and the cavitating flow images in a convergent-divergent channel. The results show that the pressure fluctuation is composed of three parts, the flow noise, the low-frequency fluctuation, and the cavity collapse induced impulse, and the pressure evolution of the quasi-periodic cloud cavitation is well consistent with the cavitation evolution. The statistical analysis of the pressure fluctuation shows that, when σ > 1.01, the probability density function (PDF) is nearly in the normal distribution, implying the randomness of the pressure fluctuation, when 0.84 1.01, when σ maximum at the cavity closure and it also increases with the decrease of the cavitation number. The spectral analysis shows that the low-frequency pressure fluctuations mainly consist of two dominant components, the cavity shedding induced fluctuation and the lock-in fluctuation. The cavity shedding induced frequency decreases with the decrease of the cavitation number but the lock-in frequency is kept nearly constant. According to the spectral analysis of the cavity area fluctuation and the modal analysis of the flow system, the lock-in is possibly caused when the fluctuation frequency of the cavity volume approaches the natural frequency of the flow system.

关键词： Cavitation pressure fluctuation statistical features lock-in phenomenon