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science China Chemistry 2015年第3期58卷 514-518页

作者： Yang Tian Yue Wang Yan Xu Yang Liu Di Li Chunhai Fan College of Life and Environmental science Minzu University of China Division of Physical Biology & Bioimaging Center Shanghai Synchrotron Radiation Facility Shanghai Institute of Applied PhysicsChinese Academy of Sciences Department of Chemistry Beijing Key Laboratory for Analytical Methods and Instrumentation Tsinghua University

In this paper, we report a highly sensitive chemiluminescence(CL) sensor for Hg2+ ions based on thymine-Hg2+-thymine(T-Hg2+-T) coordination chemistry. We designed a thymine rich oligonucleotide as a capture probe and a signal probe that includes two functional domains: a horseradish peroxidase-mimicking DNAzyme domain for the generation of CL, and a recognition domain. Graphene oxide(GO) was introduced to adsorb the signal probe via π-π interaction, which brought the DNAzyme domain and GO into close proximity and quenches CL. In the presence of Hg2+ ions, the coordination of Hg2+ with the capture probe yielded a hairpin complex, triggers cascaded strand displacement reactions and Exonuclease III-assisted signal amplifications. As a result, accumulated amounts of DNAzyme were generated and released from GO, leading to an enhanced CL signal. This strategy combines enzyme-based signal amplification and GO as a background reducer, leads to a limit of detection(LOD) of 2 nmol/L. This simple detection system provides a label-free yet sensitive approach for detection of Hg2+ ions.

关键词： graphene oxide chemiluminescence mercury(II) ions DNAzyme

Sampled-Data Consensus Control of MUSV Systems with Channel Fading and Transmission Delay

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China Communications 2020年第3期17卷 36-45页

作者： Liyuan Wang Wei Yue Rubo Zhang Key Laboratory of Intelligent Perception and Advanced Control of state ethnic affairs commission Dalian Minzu UniversityDalian 116600China College of Mechanical and Electronic Engineering Dalian Minzu UniversityDalian 116600China Marine Electrical Engineering College Dalian Maritime UniversityDalian 116026China

This paper studies sampled-data consensus control of a collection of unmanned surface vehicles(USV)operating in network environments with fading channels and time-varying transmission *** channel fading is modeled as each independent stochastic process whose probability distribution is *** considering the effects of channel fading and transmission delay from sampler to the controller,a new MUSV system model is formulated in the framework of *** the novel established model,stability analysis is given at first,then the sampled-data consensus controller is designed,which also extends to the robust control with wave-induced *** effectiveness of the presented method is demonstrated by numerical simulation.

关键词： consensus sampled-data unmanned surface vehicle fading channel time delay

Low temperature hydrothermal synthesis of SrTiO3 nanoparticles without alkali and their effective photocatalytic activity

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Journal of Advanced Ceramics 2016年第4期5卷 298-307页

作者： Hongfang SHEN Youjun LU Yanmin WANG Zhidong PAN Guozhong CAO Xianghui YAN Guoli FANG School of Materials science and Engineering South China University of Technology Guangzhou 510640 ChinaSchool of Materials Science and Engineering Beifang University of Nationalities Yinchuan 750021 China School of Materials science and Engineering Beifang University of Nationalities Yinchuan 750021 China School of Materials science and Engineering South China University of Technology Guangzhou 510640 China Department of Materials science and Engineering University of Washington Seattle WA 98195 USA

SrTiO3 nanoparticle (NP) photocatalyst was synthesized with a facile and environmentalfriendly hydrothermal method using tetrabutyltitanate,strontium oxide,and ethanolamine as precursors at low temperature without alkali as mineralizer for the first *** SrTiO3 nanoparticles were characterized by X-ray diffraction (XRD),transmission electron microscopy (TEM),field emission scanning electron microscopy (FESEM),and N2 Brunauer-Emmett-Teller (BET) *** SrTiO3 catalyst synthesized at 120 ℃ (STO-120) exhibited the highest photocurrent intensity among the samples synthesized at different hydrothermal *** high photocatalytic performance of STO-120 was mainly attributed to the more homogeneous and minimum nanoparticle size,the highest surface area,and the maximum light absorption property among the four different *** work presented an applicable and facile method to fabricate a highly active and stable SrTiO3 photocatalyst for organic pollutant degradation.

关键词： polyhedral SrTiO3 hydrothermal synthesis low temperature photocurrent property photocatalytic activity stability

Method for multi-attribute group decision-making based on the compromise weights

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Journal of Systems Engineering and Electronics 2010年第4期21卷 591-597页

作者： Shengbao Yao Wan'an Cui School of Business Administration Zhongnan University of Economics and Law Wuhan 430073 P. R. China College of Management Guangxi University for Nationalities Nanning 530006 P. R. China

Multi-attribute group decision-making problems are considered where information on both attribute weights and value scores of consequences is *** group decision analysis,if preference information about alternatives is provided by participants,it should be verified whether there exist compromise weights that can support all the preference *** different compromise weight vectors may differ for the ranking of the *** the case that compromise weights exist,the method is proposed to find out all the compromise weight vectors in order to rank the *** on the new feasible domain of attribute weights determined by all the compromise weight vectors and the incomplete information on value scores of consequences,dominance relations between alternatives are checked by a nonlinear goal programming model which can be transformed into a linear one by adopting a *** checked dominance relations uniformly hold for all compromise weight vectors and the incomplete information on value scores of consequences.A final ranking of the alternatives can be obtained by aggregating these dominance relations.

关键词： group decision-making incomplete information preference relation compromise weight.

The Number of Nonseparable Maps on the projective Plane

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Acta Mathematicae Applicatae Sinica 2010年第3期26卷 489-494页

作者： Zhao-xiang Li Li-ying Mou Fen Lei Jie Xu Department of Mathematics Minzu University of China Beijing 100081 China

In this paper, we study the rooted nonseparable maps on the sphere and the projective plane with the valency of root-face and the number of edges as parameters. Explicit expression of enumerating functions are obtained for such maps on the sphere and the projective plane. A parametric expression of the generating function is obtained for such maps on the projective plane, from which asymptotic evaluations are derived. Moreover, if the number of edges is sufficiently large, then almost all nonseparable maps on the projective plane are not triangulation.

关键词： Nonseparable maps Enumerating function Asymptotic evaluation

Unsupervised Graph-Based Tibetan Multi-Document Summarization

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Computers, Materials & Continua 2022年第10期73卷 1769-1781页

作者： Xiaodong Yan Yiqin Wang Wei Song Xiaobing Zhao A.Run Yang Yanxing School of Information and Engineering Minzu University of ChinaBeijing100081China National Language Resource Monitoring&Research Center Minority Languages BranchBeijing100081China University of California IrvineCalifornia92617USA Department of Physics New Jersey Institute of TechnologyNewarkNew Jersey07102-1982USA

Text summarization creates subset that represents the most important or relevant information in the original content,which effectively reduce information *** neural network method has achieved good results in the task of text summarization both in Chinese and English,but the research of text summarization in low-resource languages is still in the exploratory stage,especially in ***’s more,there is no large-scale annotated corpus for text *** lack of dataset severely limits the development of low-resource text *** this case,unsupervised learning approaches are more appealing in low-resource languages as they do not require labeled *** this paper,we propose an unsupervised graph-based Tibetan multi-document summarization method,which divides a large number of Tibetan news documents into topics and extracts the summarization of each *** obtained by using traditional graph-based methods have high redundancy and the division of documents topics are not detailed *** terms of topic division,we adopt two level clustering methods converting original document into document-level and sentence-level graph,next we take both linguistic and deep representation into account and integrate external corpus into graph to obtain the sentence semantic *** the shortcomings of the traditional K-Means clustering method and perform more detailed clustering of *** model sentence clusters into graphs,finally remeasure sentence nodes based on the topic semantic information and the impact of topic features on sentences,higher topic relevance summary is *** order to promote the development of Tibetan text summarization,and to meet the needs of relevant researchers for high-quality Tibetan text summarization datasets,this paper manually constructs a Tibetan summarization dataset and carries out relevant *** experiment results show that our method can effectively improve the

关键词： Multi-document summarization text clustering topic feature fusion graphic model

Synthesis of Quaternary α-Hydroxy Phosphonates via Direct Hydroxylation of Phosphonate Compounds

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Chinese Journal of Chemistry 2015年第5期33卷 559-562页

作者： Jiyan Liu Wei Wang Rui Wang Lijun Gu Key Laboratory of Chemistry in ethnic Medicinal Resources State Ethnic Affairs Commission&Ministry of EducationYunnan Minzu UniversityKunmingYunnan 650500China

It was found for the first time that Cs_(2)CO_(3) serves as highly efficient catalyst for the direct hydroxylation reactions of phosphonates under mild *** reaction provides an efficient approach to quaternaryα-hydro... 详细信息

关键词： quaternaryα-hydroxy phosphonates molecular oxygen direct hydroxylation

Far-infrared conductivity of CuS nanoparticles measured by terahertz time-domain spectroscopy

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Chinese Physics B 2010年第4期19卷 213-217页

作者：杨玉平张振伟施宇蕾冯帅王文忠 School of science Minzu University of China Department of Physics Capital Normal University

This paper reports that terahertz time-domain spectroscopy is used to measure the optical properties of CuS nanoparticles in composite samples. The complex conductivity of pure CuS nanoparticles is extracted by applying the Bruggeman effective medium theory. The experimental data are consistent with the Drude-Smith model of conductivity in the range of 0.2 1.5 THz. The results demonstrate that carriers become localized with a backscattering behaviour in small-size nanostructures. In addition, the time constant for the carrier scattering is obtained and is only 64.3 fs due to increased electron interaction with interfaces and grain boundaries.

关键词： terahertz time-domain spectroscopy conductivity effective medium theory Drude-Smith model

Light propagation properties of two-dimensional photonic crystal channel filters with elliptical micro-cavities

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Chinese Physics B 2011年第10期20卷 262-266页

作者：冯帅王义全 School of science Minzu University of China

Light propagation through a channel filter based on two-dimensional photonic crystals with elliptical-rod defects is studied by the finite-difference time-domain method. Shape alteration of the defects from the usual circle to an ellipse offers a powerful approach to engineer the resonant frequency of channel filters. It is found that the resonant frequency can be flexibly adjusted by just changing the orientation angle of the elliptical defects. The sensitivity of the resonant wavelength to the alteration of the oval rods＇ shape is also studied. This kind of multi-channel filter is very suitable for systems requiring a large number of output channel filters.

关键词： photonic crystal defect multi-channel filter micro-cavity

Effective ethanol-to-CO_(2) electrocatalysis at iridium-bismuth oxide featuring the impressive negative shifting of the working potential

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Journal of Energy Chemistry 2023年第11期86卷 23-31,I0002页

作者： Ruilin Wei Yue Liu Huazhong Ma Xingyu Ma Yaoyue Yang Key Laboratory of General Chemistry of the National ethnic affairs commission School of Chemistry and EnvironmentSouthwest Minzu UniversityChengdu 610041SichuanChina

Since low overpotential for the anodic ethanol oxidation reaction(EOR)can favor the higher output voltage and power of direct ethanol fuel cells(DEFCs),it is critical to design new EOR catalysts with efficient ethanol-to-CO_(2)activity at low applied ***,carbon-supported Ir-Bi_(2)O_(3)(Ir-Bi_(2)O_(3)/C)catalysts with highly dispersive bismuth oxide on the iridium surface are designed and prepared,which can merit splitting the ethanol C–C bond and promoting the oxidation of C1 intermediates at the bifunctional *** as-obtained Ir-Bi2O3/C catalysts show superior EOR mass activity of up to ca.2250 m A ***,they exhibit the record lowest onset oxidation potentials(0.17–0.22 V ***)and the peak potential(ca.0.58 V ***),being 130–300 m V lower than the previous landmark noble metallic ***,an apparent C1 pathway faraday efficiency(FEC1)of 28%±5.9%at 0.5 V *** can be obtained at Ir-Bi_(2)O_(3)/*** work might provide new insights into the new anodic EOR catalysts for increasing the power of DEFCs.

关键词： EOR Low overpotential C1 selectivity Iridium Bismuth oxide