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Orientations of Rare-earth-containing Heteropolyoxometalates with Different Sizes in the Interlayer of Synthetic Multibilayer Films

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Chinese Chemical Letters 2002年第9期13卷 887-890页

作者： Yong Hui wang xin long wang Chang Wen HU En Bo wang Institute of Polyoxometalate Chemistry Faculty of ChemistryNortheast Normal UniversityChangchun 130024

Three rare-earth-containing heteropolyoxometalates with different sizes, Na9[Eu(W5 O18)2], K13[Eu(SiW11O39)2], and K17[Eu(P2W17O61)2], have been incorporated by self-assembly into the interlayer of synthetic multibila... 详细信息

关键词： Rare-earth-containing heteropolyoxometalate synthetic multibilayer film DODA orientation.

Centroid-based sifting for empirical mode decomposition

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第2期12卷 88-95页

作者： Hong HONG xin-long wang Zhi-yong TAO Shuan-ping DU Key Laboratory of Modern Acoustics and Institute of Acoustics Nanjing University Nanjing 210093 China State Key Laboratory of Ocean Acoustics Hangzhou Applied Acoustics Research Institute Hangzhou 310012 China

A novel sifting method based on the concept of the 'local centroids' of a signal is developed for empirical mode decomposition (EMD), with the aim of reducing the mode-mixing effect and decomposing those modes whose frequencies are within an octave. Instead of directly averaging the upper and lower envelopes, as suggested by the original EMD method, the proposed technique computes the local mean curve of a signal by interpolating a set of 'local centroids', which are integral averages over local segments between successive extrema of the signal. With the 'centroid'-based sifting, EMD is capable of separating intrinsic modes of oscillatory components with their frequency ratio ν even up to 0.8, thus greatly mitigating the effect of mode mixing and enhancing the frequency resolving power. Inspection is also made to show that the integral property of the 'centroid'-based sifting can make the decomposition more stable against noise interference.

关键词： Sifting Empirical mode decomposition (EMD) Mode mixing effect Frequency resolution Local centroids Noise resistance

Ce(H_2O)_7Al(OH)_6Mo_6O_(18)·4H_2O: A New One-dimensional Zigzag Chainlike Structure of Anderson Cluster Linked by Cerium Ions

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Chemical Research in Chinese Universities 2005年第6期21卷 637-640页

作者： JIN Hua QI Yan-fei QIN Chao wang xin-long wang En-bo XU Lin Institute of Polyoxometalate Chemistry Faculty of Chemistry Northeast Normal University Changchun 130024 P. R. China

A new cerium polyoxomolybdate { [Ce （ H2 O） 7 Al （ OH ） 6 Mo6 O18 ] · 4H20 } （ compound 1 ） was synthesized and characterized by X-ray diffraction analysis, elemental analysis, TG analysis and IR spectrometry. Compound 1 exhibits a zigzag chain-like structure, which is constructed from an Anderson type anion and rare earth metal, Ce（ Ⅲ ）. These 1-D chains are further extended into a 3-D network by the aid of muhipoint hydrogen-bonding interactions.

关键词： One-pot reaction Zigzag chain-like polymer Rare earth metal Polyoxometalate

A highly reduced Mo_(74) polyoxometalate featuring high proton conductivity accessed by building block strategy

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Science China Chemistry 2024年第3期67卷 862-868页

作者： Shi-Yi Liu Xue-xin Li Wei-Chao Chen Kui-Zhan Shao xin-long wang Chao Qin Zhong-Min Su Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Department of ChemistryNortheast Normal UniversityChangchun 130024China State Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130021China

Highly reduced polyoxometalates(POMs) are predicted to be used as rather high energy density materials;however,it still suffers from the limited cluster species and reduction *** we demonstrate that it is possible to employ the building block strategy to generate a highly reduced polyoxomolybdate(C_(2)H_(8)N)_(14)(NH_(4))_(4)H_(14)[Mo_(48)-ⅤMo_(26)ⅥO_(202)(OH)_(12)(SO_(4))_(6)]·46H_(2)O(Mo_(74)).The fundamental Mo-based{Mo_x}(x=4,5,and 6) building blocks,which are templated by tetra-coordinated anions{MoO_(4)}or{SO_(4)},not only lay foundation for the formation of Mo_(74) featuring an unprecedented reduction ratio of 65%,but also give rise to SBBs-mediated(secondary building blocks) supramolecular dense packing interactions among the isolated Mo_(74) clusters that are favorable for proton ***,high proton conductivity(2.04×10^(-2)S cm^(-1)) had been realized at 50℃ and 90% relative humidity,revealing one of the well-known POMs-based crystalline proton conducting *** result highlights that this building block approach possesses great potential in producing highly reduced POM systems that can achieve controllable reduced ratio and desirable properties.

关键词： polyoxometalate building block molybdenum highly reduced state proton conduction

Detection of time varying pitch in tonal languages: an approach based on ensemble empirical mode decomposition

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第2期13卷 139-145页

作者： Hong HONG Xiao-hua ZHU Wei-min SU Run-tong GENG xin-long wang School of Electronic Engineering and Optoelectronic Techniques Nanjing University of Science and TechnologyNanjing 210094China State Key Laboratory of Modern Acoustics Institute of AcousticsNanjing UniversityNanjing 210093China

A method based on ensemble empirical mode decomposition (EEMD) is proposed for accurately detecting the time varying pitch of speech in tonal languages. Unlike frame-, event-, or subspace-based pitch detectors, the time varying information of pitch within the short duration, which is of crucial importance in speech processing of tonal languages, can be accurately extracted. The Chinese Linguistic Data Consortium (CLDC) database for Mandarin Chinese was employed as standard speech data for the evaluation of the effectiveness of the method. It is shown that the proposed method provides more accurate and reliable results, particularly in estimating the tones of non-monotonically varying pitches like the third one in Mandarin Chinese. Also, it is shown that the new method has strong resistance to noise disturbance.

关键词： Ensemble empirical mode decomposition Time varying pitch Tonal language Noise restraint

Organophosphate functionalized of {Mo_(240)} polyoxomolybdate dodecahedra

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Tungsten 2023年第2期5卷 247-253页

作者： Shuang-Xue Wu Yang Yang Chao Qin Yu-Han Hou xin-long wang Zhong-Min Su Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Northeast Normal UniversityChangchun 130024China College of Science Hainan UniversityHaikou 570228China

Two organophosphate-functionalized hybrid polyoxomolybdates dodecahedra(NH_(4))_(21)H^(+)59[MoⅤ_(180)Mo^(Ⅵ)60(OH)_(60)O_(620)(C_(6)H_(5)PO_(3))_(20)]·260H_(2)O(1)and(NH_(4))_(21)H^(+)59[Mo^(Ⅴ)180Mo^(Ⅵ)60(OH)_(60)O_(620)(NC_(5)H_(4)PO_(3))_(20)]·260H_(2)O(2)are constructed under hydrothermal *** both structures,20 phenylphosphonic acids or pyridyl-4-phosphonic acids are simultaneously grafted onto the interior of the{Mo_(240)}dodecahedral cage,forming an organic-inorganic polyoxomolybdate *** introduction of more strongly coordinated phenylphosphonic and pyridyl-4-phosphonic acid within the inner surface of{Mo_(240)}altered the microenvironment within the *** structures exhibit good water and thermal ***,crystals 1 and 2 were selected for adsorption of cationic dyes with the same charge and different sizes,which showed significant scavenging effect on the large size of cationic *** study provides a new perspective on the functionalization of polyoxometalate cages.

关键词： Polyoxometalates Molecular cage Functionalization Dye adsorption

DI-YOLOv5:An Improved Dual-Wavelet-Based YOLOv5 for Dense Small Object Detection

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 457-459页

作者： Zi-xin Li Yu-long wang Fei wang the Shanghai Key Laboratory of Power Station Automation Technology Shanghai University the School of Mechatronic Engineering and Automation Shanghai University IEEE the TAIHU Laboratory of Deepsea Technological Science China Ship Scientific Research Center

Dear Editor,This letter focuses on the fact that small objects with few pixels disappear in feature maps with large receptive fields, as the network deepens, in object detection tasks. Therefore, the detection of dens...

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Two polyoxovanadoborates with over 100 nuclei assembled from a {V_(14)Co_(12)B_(72)} cluster

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Science China Chemistry 2024年第8期67卷 2578-2585页

作者： Shuang-Xue Wu Yu-Jiao Dong Yang Yang Chao Qin Chun-Yi Sun Wei Guan xin-long wang Zhong-Min Su Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Northeast Normal UniversityChangchun 130024China School of Chemistry and Environmental Engineering Changchun University of Science and TechnologyChangchun 130013China Key Laboratory of Advanced Materials of Tropical Island Resources Hainan UniversityHaikou 570228China

Combining theoretical prediction and experimental exploration, the first sandwich-type polyoxovanadoborate(POVB) with an odd number of nuclei, [V_(11)B_(26)O_(73)(OH)_(10)]^(8-)(1), was discovered under hydrothermal conditions. Density-functional theory(DFT)gives a rationalization for the existence of this structure and the structural feature is consistent with the {V_NB_(2N+X)}(X = 2, 4, 6, 8)general formula. Excitingly, when Co and 1,10-phenanthroline(phen) are introduced into the synthesis of vanadoborates system,a 100-nuclei [Co_6(phen)_(10)(H_(2)O)_8][V_(14)Co_(12)B_(72)O_(144)(OH)_(20)]·28H_(2)O(2) and a 102-nuclei [Co_6(phen)_(14)(H_(2)O)_(4)][V_(14)Co_(12)B_(72)O_(144)(OH)_(20)]·23H_(2)O(3) with the same core structure of [V_(14)Co_(12)B_(72)]^(12-)are obtained. The vase-shaped [V_(14)Co_(12)B_(72)] polyanion is a multilayered sandwich-type structure containing seven distinct structural layers and is the largest known POVB. Furthermore, 2demonstrates exceptional thermal and chemical stability and serves as an efficient and stable catalyst for the photoreduction of carbon dioxide.

关键词： boronate metallic materials polyoxovanadoborates density functional theory photocatalysis CO_(2)reduction

Machine learning-assisted fluorescence visualization for sequential quantitative detection of aluminum and fluoride ions

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Journal of Environmental Sciences 2025年第3期149卷 68-78页

作者： Qiang Zhang xin Li long Yu Lingxiao wang Zhiqing Wen Pengchen Su Zhenli Sun Suhua wang School of Environmental Science and Engineering Guangdong University of Petrochemical TechnologyMaoming 525000China MOE Key Laboratory of Resources and Environmental System Optimization College of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China

The presence of aluminum(Al^(3+))and fluoride(F^(−))ions in the environment can be harmful to ecosystems and human health,highlighting the need for accurate and efficient *** this paper,an innovative approach is presented that leverages the power of machine learning to enhance the accuracy and efficiency of fluorescence-based detection for sequential quantitative analysis of aluminum(Al^(3+))and fluoride(F^(−))ions in aqueous *** proposed method involves the synthesis of sulfur-functionalized carbon dots(C-dots)as fluorescence probes,with fluorescence enhancement upon interaction with Al^(3+)ions,achieving a detection limit of 4.2 nmol/***,in the presence of F^(−)ions,fluorescence is quenched,with a detection limit of 47.6 nmol/*** fingerprints of fluorescence images are extracted using a cross-platform computer vision library in Python,followed by data ***,the fingerprint data is subjected to cluster analysis using the K-means model from machine learning,and the average Silhouette Coefficient indicates excellent model ***,a regression analysis based on the principal component analysis method is employed to achieve more precise quantitative analysis of aluminum and fluoride *** results demonstrate that the developed model excels in terms of accuracy and *** groundbreaking model not only showcases exceptional performance but also addresses the urgent need for effective environmental monitoring and risk assessment,making it a valuable tool for safeguarding our ecosystems and public health.

关键词： Machine learning Aluminum ion detection Fluorine ion detection Fluorescence probe K-means model