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Chinese Journal of Structural Chemistry 2010年第7期29卷 1115-1121页

作者： JIN Xin TANG li-ming YOU hu Laboratory of Advanced Materials Department of Chemical Engineering Tsinghua University Beijing 100084 China

Three secondary amine terminated hyperbranched poly（ester-amine）s （defined as HPEA1, HPEA2 and HPEA3） were synthesized from piperazine （A2） and trimethylolpropane triacrylate （TMPTA, B3） at their molar ratios of 2.5：1, 2.25：1 and 2.0：1, respectively. The polymers were analyzed by 1H NMR, GPC, DSC and TGA. The results indicated that the ratio of secondary amine to tertiary amine and the content of secondary amine decreased, while the molecular weight, molecular weight distribution and glass transition temperature （Tg） increased from HPEA1 to HPEA3. Due to their reactive terminal groups and flexible chains, these polymers further reacted with an epoxy resin （E51） to form cured films under ambient conditions. With increasing the ratio between secondary amine groups and epoxy groups from 1：2 to 2：1, the gel content, film hardness and onset decomposing temperature of the cured samples increased. The good film performances should make the polymers as the components of non-solvent coating materials.

关键词： hyperbranched poly(ester-amine) structure epoxy resin curing film

Distinguishing Computer-Generated Images from Natural Images Using Channel and Pixel Correlation

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Journal of Computer Science & Technology 2020年第3期35卷 592-602页

作者： Rui-Song Zhang Wei-Ze Quan Lu-Bin Fan li-ming hu Dong-ming Yan National Laboratory of Pattern Recognition Institute of AutomationChinese Academy of SciencesBeijing 100190China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China Alibaba Group Hangzhou 310023China State Key Laboratory of Hydro-Science and Engineering Tsinghua UniversityBeijing 100084China

With the recent tremendous advances of computer graphics rendering and image editing technologies,computergenerated fake images,which in general do not reflect what happens in the reality,can now easily deceive the inspection of human visual *** this work,we propose a convolutional neural network(CNN)-based model to distinguish computergenerated(CG)images from natural images(NIs)with channel and pixel *** key component of the proposed CNN architecture is a self-coding module that takes the color images as input to extract the correlation between color channels *** previous approaches that directly apply CNN to solve this problem,we consider the generality of the network(or subnetwork),i.e.,the newly introduced hybrid correlation module can be directly combined with existing CNN models for enhancing the discrimination capacity of original *** results demonstrate that the proposed network outperforms state-of-the-art methods in terms of classification *** also show that the newly introduced hybrid correlation module can improve the classification accuracy of different CNN architectures.

关键词： natural image computer-generated image channel and pixel correlation convolutional neural network

Synthesis of γ-Al2O3 with High Surface Area and Large Pore Volume by Reverse Precipitation- azeotropic Distillation Method

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Chemical Research in Chinese Universities 2013年第2期29卷 206-209页

作者： WU Yu-sheng MA Jiao li ming-chun hu Fang School of Materials Science and Engineering Shenyang University of Technology Shenyang 110870 P. R. China

γ-Al2O3 with high surface area and large pore volume combined with high thermal stability was synthe- sized by a reverse precipitation-azeotropic distillation method. The effects of azeotropic distillation on the characte- ristics of γ-Al2O3 were studied by means of X-ray diffraction（XRD）, Fourier transform infrared（FTIR） spectroscopy, transmission electron microscopy（TEM） and N2 adsorption-desorption. The results show that γ-Al2O3 dried by azeo- tropic distillation has excellent structure characteristics with a high surface area of 426 m2/g and a large pore volume of 2.56 cm3/g. After calcination at 1100 ℃, the surface area of γ-Al2O3 was still 92 mE/g with a large pore volume of 1.00 cma/g, indicating the potential application in catalyst and petroleum industry.

关键词： Reverse precipitation Azeotropic distillation y-Alumina n-Butyl alcohol Thermal stability

A facile electrochemical synthesis of caffeic acid derivatives in the presence of acetylacetone or methyl acetoacetate in aqueous medium

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Chinese Chemical Letters 2007年第2期18卷 130-132页

作者： Cheng Chu Zeng[a]&Email:zengcc@*** li ming hu[a] Jia Zeng[a] Ru Gang Zhong[a] [a]College of life Science & Bioengineering Beijing University of Technology Beijing 100022 China

The anodic oxidation of caffeic acid in the presence of acetylacetone or methyl acetoacetate in aqueous solution has been studied by cyclic voltammetry and controlled-potential electrolysis techniques. The result showed that caffeic acid was oxidized to the corresponding o-benzoquinone, which underwent further Michael-addition with acetylacetone or methyl acetoacetate to produce caffeic acid derivative 3,4-dihydroxy-6-(1-acetylacetone)-yl cinnamic acid 4a or 3,4-dihydroxy-6-(1-acetyl-methylacetate)-yl cinnamic acid 4b.

关键词： Caffeic acid Electrochemical synthesis Acetylacetone Methyl acetoacetate

Energy release characteristics of PTFE/Al/TiH_(2) reactive jet with different TiH_2 content

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Defence Technology（防务技术） 2024年第9期39卷 168-176页

作者： Chunlan Jiang Jingbo Zhang Rong hu liang Mao ming li State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

Titanium hydride(TiH_(2)), a promising high-energy additive, is doped into PTFE/Al to optimize the energy output structure of the reactive jet and strive for better aftereffect damage ability to the target. Six types of PTFE/Al/TiH_(2) reactive liners with different TiH_(2) content are prepared by the molding and sintering method. The energy release characteristics of PTFE/Al/TiH_(2) reactive jet are tested by the transient explosion energy test, and are characterized from pressure and temperature. The reaction delay time,pressure history, and temperature history of the energy release process are obtained, then the actual value of released energy and reaction efficiency of the reactive jet are calculated. The results show that the peak pressure and temperature of the PTFE/Al/TiH_(2) jet initially increase and then decrease with increasing TiH_(2) content. When the TiH_(2) content is 10%, the actual value of released energy and reaction efficiency increased by 24% and 6.4%, respectively, compared to the PTFE/Al jet. The reaction duration of the reactive material is significantly prolonged as the TiH_(2) content increased from 0% to 30%. Finally,combined with the energy release behaviors of PAT material and the dynamic deformation process of liner, the enhancement mechanism of TiH_(2) on energy release of the reactive jet is expounded.

关键词： PTFE/Al/TiH_(2) Reactive materials Shaped charge Impact energy release characteristics

Information-theoretic perspective on performance assessment and fundamental limit of quantum imaging [Invited]

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Chinese Optics Letters 2024年第6期22卷 60-67页

作者： Na li Chenyu hu Xiao-ming Lu School of Sciences Hangzhou Dianzi UniversityHangzhou 310018China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China

Performance assessment of an imaging system is important for the optimization design with various *** information-theoretic viewpoint based on communication theory or statistical inference theory can provide objective and operational measures on imaging performance. These approaches can be further developed by combining with the quantum statistical inference theory for optimizing imaging performance over measurements and analyze its quantum limits, which is demanded in order to improve an imaging system when the photon shot noise in the measurement is the dominant noise source. The aim of this review is to discuss and analyze the recent developments in this branch of quantum imaging.

关键词： quantum imaging quantum metrology quantum optics

Synthesis and characterization of poly[(4-vinylphenyl)dimethyl-silane]-b-polybutadiene-b-poly[(4-vinylphenyl)dimethylsilane](PVPDMS-b-PBd-b-PVPDMS)

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Chinese Chemical Letters 2011年第11期22卷 1371-1374页

作者： Hong Wei Ma Bai Wang Chun Qing Zhang Yang li Yan ming hu Yu Rong Wang liaoning Key Laboratory of Polymer Science and Engineering School of Chemical Engineering Dalian University of Technology Dalian Liaoning 116024 China

The novel functionalized triblock copolymers,poly[（4-vinylphenyl）dimethylsilane]-b-polybutadiene-b-poly[（4-vinylphenyl）-dimethylsilane] （PVPDMS-b-PBd-b-PVPDMS）,were synthesized by anionic polymerization method using high vacuum technique. The hydrocarbon-soluble dilithium initiator synthesized from l,3-di[l-（methylphenyl）ethenyl]benzene（MPEB） was used to synthesize polybutadiene（PBd） precursors and the triblock copolymers in the presence of *** precursors and copolymers were characterized by size exclusion chromatography（SEC）,~1HNMR and DSC techniques.

关键词： Anionic polymerization Functionalized triblock copolymers High vacuum technique

Buried interface management via bifunctional NH_(4)BF_(4)towards efficient CsPbI_(2)Br solar cells with a V_(oc)over 1.4 V

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Journal of Energy Chemistry 2024年第2期89卷 364-370,I0009页

作者： Fazheng Qiu ming-hua li Jinpeng Wu Jin-Song hu School of Materials Science and Engineering NingboTech UniversityNingbo 315100ZhejiangChina Beijing National Laboratory for Molecular Sciences(BNLMS) Institute of ChemistryChinese Academy of SciencesBeijing 100190China College of Chemical Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China

CsPbI_(2)Br perovskite solar cells(PSCs)have drawn tremendous attention due to their suitable bandgap,excellent photothermal stability,and great potential as an ideal candidate for top cells in tandem solar ***,the abundant defects at the buried interface and perovskite layer induce severe charge recombination,resulting in the open-circuit voltage(V_(oc))output and stability much lower than ***,a novel buried interface management strategy is developed to regulate interfacial carrier dynamics and CsPbI_(2)Br defects by introducing ammonium tetrafluoroborate(NH_(4)BF_(4)),thereby resulting in both high CsPbI_(2)Br crystallization and minimized interfacial energy ***,NH_(4)^(+)ions could preferentially heal hydroxyl groups on the SnO_(2)surface and balance energy level alignment between SnO_(2)and CsPbI_(2)Br,enhancing charge transport efficiency,while BF_(4)^(-)anions as a quasi-halogen regulate crystal growth of CsPbI_(2)Br,thus reducing perovskite ***,it is proved that eliminating hydroxyl groups at the buried interface enhances the iodide migration activation energy of CsPbI_(2)Br for strengthening the phase *** a result,the optimized CsPbI_(2)Br PSCs realize a remarkable efficiency of 17.09%and an ultrahigh V_(oc)output of 1.43 V,which is one of the highest values for CsPbI_(2)Br PSCs.

关键词： Inorganic perovskite Buried interface Defect Stability Open-circuit voltage loss

Near real-time gravitational wave data analysis of the massive black hole binary with TianQin

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 175-186页

作者： Hong-Yu Chen Xiang-Yu Lyu En-Kun li Yi-ming hu MOE Key Laboratory of TianQin Mission TianQin Research Center for Gravitational Physics&School of Physics and AstronomyFrontiers Science Center for TianQinGravitational Wave Research Center of CNSASun Yat-sen University(Zhuhai Campus)Zhuhai 519082China

Space-borne gravitational wave(GW)detectors can detect the merger of massive black *** early warning and localization of GW events before merging can be used to inform electromagnetic telescopes and conduct multimessenger ***,this requires real-time data transmission and analysis *** geocentric orbit of the space-borne GW detector Tian Qin makes it possible to conduct real-time data *** this study,we develop a search and localization pipeline for massive black hole binaries(MBHBs)with Tian Qin under both regular and real-time data transmission *** demonstrate that,with real-time data transmission,MBHBs can be accurately localized on the *** the approaching merger,each analysis can be finished in only 40 *** an MBHB system at a distance of 1 Gpc,if we receive data every hour,then we can pinpoint its location to within less than 1 deg^(2)on the final day before the merger.

关键词： gravitational wave detectors and experiments black holes data analysis algorithms and implementation data management

High-temperature stability of retained austenite and plastic deformation mechanism of ultra-fine bainitic steel isothermally treated below Ms

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Journal of Iron and Steel Research International 2024年第8期31卷 2014-2030页

作者： Ting-ting He Feng hu Kun Wang Wen Zhou li li Serhii Yershov Kai-ming Wu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Collaborative Innovation Center for Advanced Steels Wuhan University of Science and TechnologyWuhan 430081HubeiChina Zhejiang Tsingshan Iron and Steel Co. Ltd.Qingtian 323903ZhejiangChina

The mechanical properties of the sample and the stability of retained austenite were studied by designing two kinds of ultra-fine bainitic steel with different heat treatment methods austempering above and below Ms(martensite start tem-perature),which were subjected to tensile tests at 20 and 450℃,*** results show that compared to room temperature(20℃)tensile properties,the uniform elongation of the sample at high temperature(450℃)significantly ***,the uniform elongation of the sample austempered above Ms decreased from 8.0%to 3.5%,and the sample austempered below Ms decreased from 10.9%to 3.1%.Additionally,the tensile strength of the sample austempered above Ms significantly decreased(from 1281 to 912 MPa),and the sample austempered below Ms slightly decreased(from 1010 to 974 MPa).This was due to the high carbon content(1.60 wt.%),high mechanical stability,low thermal stability for the retained austenite of the sample austempered below ***,the retained austenite decomposed at high temper-atures,the carbon content and transformation driving force were significantly reduced,the transformation rate increased,and the phase transformation content reduced.

关键词： Ultra-fine bainite Isothermal treatment High-temperature tensile property Retained austenite stability Plastic deformation