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Chinese Chemical Letters 1995年第12期6卷 1059-1060页

作者： Hao Ran SUN gou yu yang Jia Ning XU Ji Qing XU (Department of Chemistry,Chemistry, Jilin University, Changchan, 130023)

In the paper, we have studied the mixed-valence isopolyanion by cyclic voltammogram, in-situ UV-Visible-Near-IR and FTIR spectroelectrochemical methods in aprotic medium,such as methylene chloride.A number of hetero-- and iso--polyanions of molybdenum are re(luci})leto a series of mixed-valeDce compounds containing Mow and Mo t'. f 1 1These species exhibit intervalence transfer bands. This description ofthe electronic structure corresponds to cia88 H syetems in Robinand Day'8 classification of mixed--valence compounds t21. The electrochemical methods can prepare the mixed--valence compounds in which laceetructure of the parent oxidized form is generally retained. [31 In--situepectroelectrochemical studies have many advantages for product identification and for mechanistic studies of transition metal complexes in solution. t.1 Among theme are small electrolysis volumee that yield shortelectrolysis times, rapid time response for the measurement or kineticparameters, and the rapid in--situ generation of reactive species withBtable properties that preclude isolation [*** cyclic voltammogram indicates that the (TBA).Mo.O.. undergoestwo reductione, which are labeled ac reactions 1--2 and corre6pond tothe electron transfers given in eq. 1-- ***.O.g-- + e * Mo.O.g--' E./2=--0.690V -----------------------------(1)Mo.O.S-- + e - Mo.O.:-- ac- other products E.,.=--1.650V------(2)

关键词： FTIR SITU VISIBLE APROTIC AND Mo UV

地区全球化的一种新模式——以广州狮岭镇皮具产业为例

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地理科学 2009年第3期29卷 336-341页

作者：吕拉昌余国扬高晶华刘毅华林彰平广州大学广州发展研究院广东广州510006 广州大学地理科学学院广东广州510006

全球化与地区化是两个相对的过程,其相互作用是通过两个重要的过程:全球地区化与地区的全球化,对全球地区化过程已有许多研究成果,但对地区全球化过程的研究相对较少。基于广州花都狮岭镇皮具产业集群的案例研究,认为在贸易导向型的专... 详细信息

全球化与地区化是两个相对的过程,其相互作用是通过两个重要的过程:全球地区化与地区的全球化,对全球地区化过程已有许多研究成果,但对地区全球化过程的研究相对较少。基于广州花都狮岭镇皮具产业集群的案例研究,认为在贸易导向型的专业化产业集群的基础上,发展中国家的地区形成了产业集群—专业市场—会展经济的"地区结构",这一结构形成了发展中国家自下而上的地区全球化的新模式。这一模式提出的意义在于对于发展中国家,全球化不仅是生产领域的全球化,也包括流通与市场领域,发展中国家的产业全球化需要一种系统的"地区结构",这是地区走向全球的重要途径。

关键词：全球化全球地区化地区全球化地区结构

Photonic generation of ASK microwave signals with SSB format

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Frontiers of Optoelectronics 2023年第3期16卷 35-41页

作者： Weilei gou yuan yu Xinliang Zhang Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China Optics Valley Laboratory Wuhan 430074China

Optical beating is the usual approach to generation of microwave ***,the highest frequency achievable for microwave signals is limited by the bandwidths of optoelectronic *** maximize the microwave frequency with a limited bandwidth of a photodetector(PD)and relieve the bandwidth bottleneck,we propose to generate microwave signals with the single sideband(SSB)format by beating a continuous wave(CW)light with an optical SSB *** simply adjusting the frequency diference between the CW light and the carrier of the optical SSB signal,the frequency of the generated microwave SSB signal is changed *** the experiment,amplitude shift keying(ASK)microwave signals with the SSB format are successfully generated with diferent carrier frequencies and coding bit rates,and the recovered coding information agrees well with the original pseudo random binary sequence(PRBS)of 2^(7)−1 *** proposed approach can signifcantly relieve the bandwidth restriction set by optoelectronic devices in high-speed microwave communication systems.

关键词： Single sideband modulation Amplitude shift keying Microwave signal generation Microwave communication

Effect of air bubble size on cavitation erosion reduction

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Science China(Technological Sciences) 2017年第4期60卷 523-528页

作者： WU JianHua SU KunPeng WANG yu gou WenJuan College of Water Conservancy and Hydropower Engineering Hohai University State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University

Over the past 60 years, the air concentration in water has been considered as a control index of cavitation erosion reduction and widely used in the designs of hydraulic structures. However, the mechanism of air entrainment against cavitation erosion has been paid good attention to. In the present work, the effect of air bubble size on cavitation erosion reduction was experimentally investigated. A device with micron-scale orifice diameters(10, 20 and 50 μm in size) was specially designed to introduce air bubbles into water. The experiments about the effect of air bubble size were conducted by means of a vibratory apparatus, including the behavior of formation and movement for single air bubble, the characteristics of cavitation erosion reduction at different air entrainment conditions. The findings demonstrate that high air concentration has significant effects on cavitation erosion ***, a notable problem was that the size of air bubbles is of outstanding effect on cavitation erosion reduction. Small air bubbles support to alleviate cavitation erosion, even at same air concentration.

关键词： air bubble size air entrainment cavitation erosion micron-scale

Barrier or easy-flow channel: The role of grain boundary acting on vortex motion in type-Ⅱ superconductors

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Chinese Physics B 2021年第9期30卷 499-505页

作者： yu Liu Xiao-Fan gou Feng Xue College of Mechanics and Materials Hohai UniversityNanjing 211100China

Grain boundaries(GBs),as extremely anisotropic pinning defects,have a strong impact on vortex motion in type-Ⅱsuperconductors,and further on the macro level dominates the superconductivity for example the critical current *** previous studies indicated that mostly GB plays the role of a strong barrier for vortex motion,while an easy-flow channel just under some certain *** order to thoroughly make clear of the questions of what is exactly the role of GB on vortex motion and how it works,in this article we developed a large scale molecular dynamic model and revealed the action of GB on vortex motion in type-Ⅱ*** most significant finding is that the role of GB on vortex motion can be changeable from a barrier to an easy-flow channel,and which is intrinsically determined by the competition effect correlated with its action on vortex between in the GB and no-GB *** the competition effect essentially depends on the attributes of both the GB(described by the GB strength and angleθ)and no-GB pining regions(by the relative disorder strengthα_(p)/α_(v)).Specifically,for a YBa_(2)Cu_(3)O_(7-x)(YBCO)sample,to obtain a clear knowledge of vortex motion in GB region,we visualized the three typical trajectories of vortices during the three vortex movement ***,in order to understand how GB results in the macro current-carrying property,corresponding to the current-voltage relation of the YBCO conductor,we obtained the average velocity v_(y) of vortices varying with their driving force,which is nearly identical with the previous observations.

关键词： type-II superconductors grain boundary(GB) vortex motion competition effect GB strength the relative disorder strengthαp/αv

Organocatalytic asymmetric[2+2] cycloaddition of alkynes with quinones

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Science China Chemistry 2023年第8期66卷 2292-2299页

作者： Huai-Ri Sun Lan yang yu Li Le yu Bo-Bo gou Atif Sharif Qing-Song Jian Jie Chen Ling Zhou Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi’an710127China

A chiral phosphoric acid catalyzed enantioselective[2+2] cycloaddition of alkynylindols or alkynylnaphthols with quinones is disclosed.A class of functionalized cyclobutenes with excellent yields,diastereo-and enantioselectivities were prepared under mild reaction conditions(70 examples,up to 99%yield,99%ee,all>50:1 dr).Mechanistic studies revealed that a dearomatization of indole or naphthol occurred to initiate the cycloaddition,followed by an intramolecular Michael addition with in situ generated allene-iminium or vinylidene-quinone methide *** competitive[2+3] cycloaddition was prevented in this catalytic *** interesting central to axial chirality conversion via a rearrangement process was realized during transformation of the product.

关键词： organocatalysis [2+2]cycloaddition asymmetric catalysis alkynes cyclobutenes

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基于基因组重测序的沉香遗传多样性研究

热带作物学报 2025年第1期46卷 51-58页

作者：苟志辉陈国德甄云楠王鑫陈彧田蜜海南省林业科学研究院(海南省红树林研究院) 海南海口571100 海南省热带林业资源监测与应用重点实验室海南海口571100 海口市湿地保护管理中心海南海口571100

对种质资源信息的掌握是土沉香遗传改良的基础,而基因组重测序是种质资源遗传多样性分析的利器,然而目前学术界缺乏利用基因组重测序对土沉香遗传多样性的研究。本研究在前期收集得到的沉香种质资源基础上,采用基因组重测序,获得60份沉... 详细信息

对种质资源信息的掌握是土沉香遗传改良的基础,而基因组重测序是种质资源遗传多样性分析的利器,然而目前学术界缺乏利用基因组重测序对土沉香遗传多样性的研究。本研究在前期收集得到的沉香种质资源基础上,采用基因组重测序,获得60份沉香共1284 Gb重测序数据。利用沉香基因组,共检测得到6 713 166个高质量变异位点,其中SNP位点6 284 344个,Indel位点428 658个。主成分分析、系统发育分析和遗传结构分析均表明,沉香可分为3个显著群体(Pop1、Pop2和Pop3),其中2个群体可分别进一步划分为多个亚群。在3个群体中均检测到群体选择信号,其中Pop3选择信号最多,而核苷酸多态性计算结果表明,Pop3的核苷酸多态性最低。本研究为探究沉香遗传资源多样性提供了有价值的信息,并为基于基因组的沉香遗传育种奠定理论基础。

关键词：沉香基因组重测序变异位点遗传多样性

The Spin Measurement of MAXI J0637-430:a Black Hole Candidate with High Disk Density

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Research in Astronomy and Astrophysics 2023年第7期23卷 277-287页

作者： Nan Jia Ye Feng yu-Jia Song Jun yang Jieun yuh Pei-Jun Huang Li-Jun gou Key Laboratory for Computational Astrophysics National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China Shanghai American School Puxi Campus Shanghai 201107China Shenzhen Yaohua Experimental School Shenzhen 518034China

The Galactic black hole candidate MAXI J0637-430 was first discovered by MAXI/GSC on 2019 November *** study the spectral properties of MAXI J0637-430 by using the archived NuSTAR data and Swift/XRT *** fitting the eight spectra by using a disk component and a powerlaw component model with absorption,we select the spectra with relatively strong reflection components for detailed X-ray reflection *** the most state-of-art reflection model,relxillCp,the spectral fitting measures a black hole spin a_(*)>0.72 and the inclination angle of the accretion disk i=46.1_(-5.3)^(+4.0)degrees,at a 90%confidence *** addition,the fitting results show an extreme supersolar iron *** with the fitting results of reflection model reflionx_hd,we consider that this unphysical iron abundance may be caused by a very high-density accretion disk(n_(e)>2.34×10^(21)cm^(-3))or a strong Fe K_(α) emission *** soft excess is found in the soft state spectral fitting results,which may be an extra free-free heating effect caused by high density of the accretion ***,we discuss the robustness of black hole spin obtained by X-ray reflection *** result of relatively high spin is self-consistent with broadened Fe K_(α) *** abundance and disk density have no effect on the spin results.

关键词： black hole physics X-rays:binaries accretion accretion disks

Pose-robust feature learning for facial expression recognition

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Frontiers of Computer Science 2016年第5期10卷 832-844页

作者： Feifei ZHANG Yongbin yu Qirong MAO Jianping gou Yongzhao ZHAN School of Computer Science and Communication Engineering Jiangsu University Zhenjiang 212013 China

Automatic facial expression recognition （FER） from non-frontal views is a challenging research topic which has recently started to attract the attention of the research community. Pose variations are difficult to tackle and many face analysis methods require the use of sophisticated nor- malization and initialization procedures. Thus head-pose in- variant facial expression recognition continues to be an is- sue to traditional methods. In this paper, we propose a novel approach for pose-invariant FER based on pose-robust fea- tures which are learned by deep learning methods -- prin- cipal component analysis network （PCANet） and convolu- tional neural networks （CNN）（PRP-CNN）. In the first stage, unlabeled frontal face images are used to learn features by PCANet. The features, in the second stage, are used as the tar- get of CNN to learn a feature mapping between frontal faces and non-frontal faces. We then describe the non-frontal face images using the novel descriptions generated by the maps, and get unified descriptors for arbitrary face images. Finally, the pose-robust features are used to train a single classifier for FER instead of training multiple models for each spe- cific pose. Our method, on the whole, does not require pose/ landmark annotation and can recognize facial expression in a wide range of orientations. Extensive experiments on two public databases show that our framework yields dramatic improvements in facial expression analysis.

关键词： facial expression recognition pose-robust fea-tures principal component analysis network (PCANet) con-volutional neural networks (CNN)

VUV photoluminescence properties of KSrPO4：Dy^3＋ phosphor

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Journal of Rare Earths 2018年第8期36卷 802-805页

作者： Yali Chen Jingyan Fan Yajun Zhou Jing gou Binxun yu Key Laboratory of Applied Surface and Colloid Chemistry Ministry of Education Shaanxi Normal University. Xi'an 710119 China Shaanxi Key Laboratory for Advanced Energy Devices Shaanxi Engineering Laboratory for Advanced Energy Technology School of Materials Science andEngineering Shaanxi Normal University. Xi'an 710119 China School of Chemistry and Chemical Engineering. Shaanxi Normal University Xi'an 710119 China

White-light-emitting phosphors based on phosphate host matrix, KSrPO4 doped with Dy^3＋, were prepared by solid state reaction and their VUV luminescent properties were firstly investigated. The excitation band peaking at 125-153 nm corresponding to the absorption of PO4^3- group exhibits very strong absorption. The phosphors emit warm-white luminescence under vacuum ultraviolet excitation of 147 nm, which consists of three main emission peaks located at 475, 570 and 662 nm, *** to the luminescence and color chromaticity of the optimal sample KSrPO4：1 mol%Dy^3＋,1.3 mol%Li^＋, it can be a potential candidate for mercury-free fluorescent lamps.

关键词： Phosphor Photoluminescence VUV Rare earths