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Journal of Materials Science & Technology 2018年第12期34卷 2331-2336页

作者： Jun xiao Weiyi Yang Shuang gao Caixia Sun Qi Li Environment Functional Materials Division Shenyang National Laboratory for Materials ScienceInstitute of Metal ResearchChinese Academy of SciencesShenyong 110016China University ofChineseAcademy of Sciences Beijing 100049China Division of Energy and Environment Graduate School of ShenzhenTsinghua UniversityShenzhen 518055China Key Laboratory of New Metallic Functional Materials and Advanced Surface Engineering in Universities of Shandong Qingdao Binhai UniversityQingdao 266555China School of Mechanical and Electronic Engineering Qingdao Binhai UniversityQingdao 266555China

A one-pot, solvent-thermal process was used to create the ultrafine ZnFe2O4nanoparticles *** the solvent-thermal process, the in situ self-forming NaCl not only served as a "cage" to confine the ion diffusion, but also acted as a microreactor for nanocrystallite growth. An average particle size of ～10 nm and a high-specific surface area of～112.9 m2/g were observed for the ultrafine ZnFe2O4nanoparticles Owing to the synergistic effect of ultrafine particle size, the full utilization of the visible light region and high conduction band(CB) position, ultrafine ZnFe2O4photocatalyst displayed an efficient photocatalytic CO2reduction under visible light illumination. Besides, the ultrafine ZnFe2O4photocatalyst showed high production selectivity for CH3CHO and C2H5OH generation in aqueous CO2/NaHCO3solution. This work may provide a new idea for the synthesis of new high-efficiency photocatalysts.

关键词： Ultrafine nanoparticles Photocatalytic CO_2 reduction Visible light ZnFe_2O_4 photocatalyst In situ self-formed "cage"

Object Recognition Based on Improved Context Model

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Chinese Journal of Electronics 2018年第3期27卷 573-581页

作者： WEN Chenglin ZHOU Guangfu gao Jingli LI Hongwei XU Xiaobin School of Automation Hangzhou Dianzi University College of Electrical Engineering Zhejiang University

An object recognition method is proposed in this paper by introducing the spatial location relationship of objects into the context model. The spatial-position information of the objects is first utilized to model the context model. The model parameters and dependency structure of objects can be learned by integrating the context information into the same probabilistic framework. The image recognition is accomplished by using the advantages of efficient inference of the tree structure model. The proposed method can greatly improve the object recognition rate and better keep the consistency of scenes. The effectiveness of the proposed algorithm is verified by testing and comparing with other existing algorithms in the actual dataset.

关键词： Context model Tree model Co-occurrence tree Spatial relationships

Investigation of extraction fraction in confined impinging jet reactors for tri-butyl-phosphate extracting butyric acid process

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Chinese Journal of Chemical Engineering 2016年第2期24卷 310-316页

作者： Zhengming gao Manting Zhao Yun Yu Zhipeng Li Jing Han State Key Laboratory of Chemical Resource Engineering School of Chemical EngineeringBeijing University of Chemical Technology beijing Aircraft Maintenance & Engineering Co. LTD

The extraction fraction E and overall volumetric mass transfer coefficient kka of TBP extracting butyric acid pro- cess in confined impinging jet reactors （CIJR） with two jets were investigated. The main variables tested were the concentration of tri-butyl-phosphate （TBP） and butyric acid, the impinging velocity V, the impinging velocityratio of two phases Vorg/Vaq, the nozzle inner diameter di and the distance L between the jet axes and the top wall of the impinging chamber. The results showed that E and kLa increase with an increase of the impinging velocity V, the concentration ofTBP Corg, and the impinging velocity ratio Vor/Vaq. However, E and kta decrease with an increase of the inner diameter d1 from 1 to 2 mm, the concentration of butyric acid Caq from 0.5% （v/v） to 2% （v/v）. The factor L ranging from 3 to 11 mm has a negligible effect on E and kLa. A correlation on these variables and kLa was proposed based on the experimental data. These results indicated good mass transfer oerformance of CIJR in the extraction operation.

关键词： Confined impinging jet reactors (CIJR) Extraction fraction Mass transfer coefficient Extraction process

Distributed cooperative control of multiple high-speed trains under a moving block system by nonlinear mapping-based feedback

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Science China(Information Sciences) 2018年第12期61卷 22-33页

作者： Bin NING Hairong DONG Shigen gao Tao TANG Wei ZHENG State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University National Research Center of Railway Safety Assessment Beijing Jiaotong University

Although the high-speed railways in China have been greatly advanced in the past decades with respect to expanding networks and increasing speed, a fixed block system, which separates the trains with several stationary track block sections, is utilized to guarantee the safe operation of multiple trains. A moving block system, which enables the moving authority of a high-speed train to be the real-time positioning point of its preceding one(plus some necessary safe redundant distance, of course), is under development to further make full use of the high-speed railway lines and improve the automation level by automatic train operation for high-speed trains. The aim of this paper is to design a distributed cooperative control for high-speed trains under a moving block system by giving a cooperative model with a back-fence communication topology. A nonlinear mapping-based feedback control method together with a rigorous mathematic proof for the global stability and ultimate bound of the closed-loop control systems is proposed. Comparative results are given to demonstrate the effectiveness and advantages of the proposed method.

关键词： high-speed trains moving block system cooperative control

Enriching short text representation in microblog for clustering

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Frontiers of Computer Science 2012年第1期6卷 88-101页

作者： Jiliang TANG Xufei WANG Huiji gao Xia HU Huan LIU Computer Science ＆ Engineering Arizona State University Tempe AZ 85281 USA

Social media websites allow users to exchange short texts such as tweets via microblogs and user status in friendship networks. Their limited length, pervasive abbrevi- ations, and coined acronyms and words exacerbate the prob- lems of synonymy and polysemy, and bring about new chal- lenges to data mining applications such as text clustering and classification. To address these issues, we dissect some poten- tial causes and devise an efficient approach that enriches data representation by employing machine translation to increase the number of features from different languages. Then we propose a novel framework which performs multi-language knowledge integration and feature reduction simultaneously through matrix factorization techniques. The proposed ap- proach is evaluated extensively in terms of effectiveness on two social media datasets from Facebook and Twitter. With its significant performance improvement, we further investi- gate potential factors that contribute to the improved perfor- mance.

关键词： short texts text representation multi-languageknowledge matrix factorization social media

Polycarbonate/Polypropylene/Fibrillar Silicate Ternary Nanocomposites: Morphology and Mechanical Properties

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Journal of Materials Science & Technology 2006年第1期22卷 87-92页

作者： Xiang gao Lixin MAO Ming TIAN Liqun ZHANG Riguang JIN College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China

Polycarbonate （pc）/polypropylene （pp）/silicate attapulgite （AT） ternary nanocomposites were first prepared via the two-step melt blending process. Phase structure of the ternary composites was characterized by transmission electron microscopy （TEM） and dynamic mechanical analysis （DMA）, in which the morphology of encapsulation of AT by PP in the PC matrix were observed. The mechanical properties of the ternary composites were investigated using the tensile tester and Izod impact tester. The results show that encapsulation of AT by PP in PC enhances the toughness of the matrix effectively and give the best tensile and impact strength.

关键词： Polycarbonate Polypropylene Attapulgite Morphology Property

Projection-based Consistent Test for Linear Regression Model with Missing Response and Covariates

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Acta Mathematicae Applicatae Sinica 2020年第4期36卷 917-935页

作者： Su-jin ZHENG Si-yu gao Zhi-hua SUN China Institute for Actuarial Science/School of Insurance Central University of Finance and EconomicsBeijing 100081China School of Mat hematic Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Big Data Mining and Knowledge Management of Chinese Academy of Sciences Beijing 100049China

In recent years,there has been a large amount of literature on missing *** of them focus on situations where there is only missingness in response or *** this paper,we consider the adequacy check for the linear regression model with the response and covariates missing *** apply model adjustment and inverse probability weighting methods to deal with the missingness of response and covariate,*** order to avoid the curse of dimension,we propose an empirical process test with the linear indicator weighting *** asymptotic properties of the proposed test under the null,local and global alternative hypothe tical models are rigorously investigated.A consisten t wild boot strap method is developed to approximate the critical ***,simulation studies and real data analysis are performed to show that the proposed method performed well.

关键词： consistency linear indicator weighting function empirical process missing response and covariates projection

Photovoltaics:Special Issue Dedicated to Professor Yongfang Li

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Aggregate 2022年第3期3卷 1-2页

作者： Lei Meng Feng gao Institute of Chemistry Chinese Academy of SciencesHaidianChina Department of Physics Chemistry and Biology(IFM)Linköping UniversityLinköpingSweden

It is a great honor for us to edit this special issue dedicated to *** Li,one of the pioneers of organic solar cell(OSC)research in *** Li was born in 1948 in Chongqing,*** obtained his master degree in 1982 at East China University of Science and Technology,Shanghai,and his *** in 1986 at Fudan University in the major of Physical Chemistry(Electrochemistry).

关键词： Chongqing China pioneer

Recent advances in the catalytic conversion of CO_2 to value added compunds

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Science China Chemistry 2015年第1期58卷 79-92页

作者： Hui Wang Peng gao Tiejun Zhao Wei Wei Yuhan Sun Center for Greenhouse Gas and Environmental Engineering Shanghai Advanced Research Institute Chinese Academy of Sciences CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research Institute Chinese Academy of Sciences

CO2 is a major greenhouse gas,and it can also be used as a chemical feedstock for synthesis of chemicals and fuels by passing the petrochemical ***,we present the recent progress of our research work in the catalytic conversion of CO2 to chemicals,with particular attention paid to catalytic reactivity and reaction *** also give the recommendations regarding the challenges and potential directions of the future research in this field.

关键词： CO2 conversion chemicals catalysts hydrogenation reforming

A comparative study and evaluation of sulfamethoxazole adsorption onto organo-montmorillonites

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Journal of Environmental Sciences 2014年第12期26卷 2535-2545页

作者： Laifu Lu Manglai gao Zheng Gu Senfeng Yang Yuening Liu State Key Laboratory of Heavy Oil Processing College of Science China University of Petroleum

Three organo-montmorillonites were prepared using surfactants, and their adsorption behaviors toward sulfamethoxazole（SMX） were investigated. The surfactants used were cetyltrimethyl ammonium bromide（CTMAB）, 3-（N,N-dimethylhexadecylammonio） propane sulfonate（HDAPS） and 1,3-bis（hexadecyldimethylammonio）-propane dibromide（BHDAP）. The properties of the organo-montmorillonites were characterized by X-ray diffraction, scanning electron microscopy and N2adsorption–desorption isotherm measurements. Results showed that the interlayer spacing of montmorillonite was increased and the surface area as well as the morphology were changed. Batch adsorption experiments showed that the surfactant loading amount had a great effect on the adsorption of SMX. The adsorption process was p H dependent and the maximum adsorption capacity was obtained at p H 3 for HDAPS-Mt, while CTMAB-Mt and BHDAP-Mt showed a high removal efficiency at 3–11. The adsorption capacity increased with the initial SMX concentration and contact time but decreased with increasing solution ionic *** data were best described by the pseudo second-order model. Equilibrium data were best represented by the Langmuir model, and the Freundlich constant（n） indicated a favorable adsorption process. The maximum adsorption capacity of SMX was 235.29 mg/g for CTMAB-Mt, 155.28 mg/g for HDAPS-Mt and 242.72 mg/g for BHDAP-Mt. Thermodynamic parameters were calculated to evaluate the spontaneity and endothermic or exothermic nature. The adsorption mechanism was found to be dominated by electrostatic interaction,while hydrophobic interaction played a secondary role.

关键词： Organo-montmorillonite Adsorption Sulfamethoxazole Cetyltrimethyl ammonium bromide Zwitterionic surfactant Gemini surfactant