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Fluorescence dynamics of interactions between polyamide PyPyPyβDp and DNA

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science China Chemistry 2006年第1期49卷 75-80页

作者： ZHANG Huijuan1,2. WANG Jin3. WU Yishi1, YUAN Gu3. AI Xicheng1, WANG Li4.& ZHANG Jianping1 1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species, institute of Chemistry, Chinese Academy of {3.s, Beijing 100080, China {2., Beijing institute of technology, Beijing 100081, China 3. College of Chemistry and Molecular Engineering, Peking University, Beijing 100080, China 4. Center for Condensed Matter Physics, institute of Physics, Chinese Academy of {3.s, Beijing 100080, China Correspondence should be addressed to Ai Xicheng and Zhang Jianping 1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 2. school of life science and technology Beijing Institute of Technology Beijing 100081 China 3. College of Chemistry and Molecular Engineering Peking University Beijing 100080 China 4. Center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

The photophysical properties of the polyamide PyPyPyβDp (PPP) were investigated by means of steady-state absorption and fluorescence spectroscopies, as well as time-resolved fluo-rescence spectroscopy. It was found that the excited-state properties of PPP are very sensitive to solvents. In TKMC buffer PPP exhibited weak fluorescence with a decay time constant of 16 ps, while with the decrease of the solvent polarity PPP showed the blue-shifted peak position, increased inten-sity and lengthened life-time for its fluorescence behavior. In the presence of calf thymus DNA, it was observed that the fluorescence intensity was enhanced and the fluorescence lifetime increased from 16 to 3.2}ps for PPP, which verified that PPP bound into the minor groove of DNA duplex.

关键词： polyamide (PPP), calf thymus DNA (ctDNA), time-resolved fluorescence spectroscopy, recognition dynamics.

Analysis and application of automatic deformation monitoring data for buildings and structures of mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 516-522页

作者： XIAO Jie1, 2. 3. ZHANG Jin4.1. institute of Geodesy and Geophysics, Chinese Academy of {3.s, Wuhan 4.0077, China 2. Key Laboratory of Dynamic Geodesy, institute of Geodesy and Geophysics, Chinese Academy of {3.s, Wuhan 4.0077, China 3. Graduate school of Chinese Academy of {3.s, Beijing 10004., China 4. Department of Surveying and Mapping, Taiyuan University of {13., Taiyuan 03.02., China Taiyuan Univ Technol Dept Surveying & Mapping Taiyuan 030024 Peoples R China Chinese Acad Sci Inst Geodesy & Geophys Key Lab Dynam Geodesy Wuhan 430077 Peoples R China Chinese Acad Sci Grad Sch Beijing 100049 Peoples R China

The buildings and structures of mines were monitored automatically using modern surveying technology. Through the analysis of the monitoring data, the deformation characteristics were found out from three aspects containing points, lines and regions, which play an important role in understanding the stable state of buildings and structures. The stability and deformation of monitoring points were analysed, and time-series data of monitoring points were denoised with wavelet analysis and Kalman filtering, and exponent function and periodic function were used to get the ideal deformation trend model of monitoring points. Through calculating the monitoring data obtained, analyzing the deformation trend, and cognizing the deformation regularity, it can better service mine safety production and decision-making.

关键词： wavelet analysis Kalman filtering deformation monitoring data analysis mine

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咖啡因的科学共识

中国食品学报 2024年第6期24卷 498-504页

作者：中国食品科学技术学会北京10004.

咖啡因是一种常见于咖啡、茶叶和可可等植物中的天然活性成分,作为功能添加成分已在国际食品领域广泛应用多年,适量摄入有助于健康人群提高注意力,促进运动能力,缓解疲劳。国内外相关食品安全监管机构一致认为,咖啡因虽在日常饮食中的... 详细信息

咖啡因是一种常见于咖啡、茶叶和可可等植物中的天然活性成分,作为功能添加成分已在国际食品领域广泛应用多年,适量摄入有助于健康人群提高注意力,促进运动能力,缓解疲劳。国内外相关食品安全监管机构一致认为,咖啡因虽在日常饮食中的摄入是安全的,但需关注个体差异、摄入量以及频率。许多国家和地区已对咖啡因在食品中的应用制定了严格的应用限量和标识规定。为进一步提升大众对咖啡因的科学认知,消除对咖啡因的偏见,推动咖啡因在相关食品产业的合理应用,中国食品科学技术学会组织食品科学、公共卫生、食品安全与食品营养等领域专家与相关产业界代表,通过现场咨询、文献检索、专题研讨等形式和方法,经广泛讨论形成咖啡因的科学共识,以推动咖啡因在我国的规范使用。

关键词：咖啡因健康益处摄入量应用管理

On the new results of global attractive set and positive invariant set of the Lorenz chaotic system and the applications to chaos control and synchronization

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science in China(Series F) 2005年第3期48卷 304-321页

作者： LIAO Xiaoxin 1, 2. 3., FU Yuli 4.& XIE Shengli 4.1. Department of Control {3. & Control Engineering, Huazhong University of {3. & {2., Wuhan 4.0074. China 2. {3. of Automation, Wuhan University of {3. & {2., Wuhan 4.0070, China 3. {3. of Information, Central South University of Economy, Politics and Law, Wuhan 4.0064. China 4. {3. of Electronics & Information Engineering, South China University of {2., Guangzhou 51064., China Correspondence should be addressed to Liao Xiaoxin (email: xiaoxin_liao@***) 1. Department of Control science & Control Engineering Huazhong University of Science & Technology 430074 Wuhan China 2. school of Automation Wuhan University of Science & Technology 430070 Wuhan China 3. school of Information Central South University of Economy Politics and Law 430064 Wuhan China 4. school of Electronics & Information Engineering South China University of Technology 510640 Guangzhou China

Constructing a family of generalized Lyapunov functions, a new method is proposed to obtain new global attractive set and positive invariant set of the Lorenz chaotic system. The method we proposed greatly simplifies the complex proofs of the two famous estimations presented by the Russian scholar Leonov. Our uniform formula can derive a series of the new estimations. Employing the idea of intersection in set theory, we extract a new Leonov formula-like estimation from the family of the estimations. With our method and the new estimation, one can confirm that there are no equilibrium, periodic solutions, almost periodic motions, wandering motions or other chaotic attractors outside the global attractive set. The Lorenz butterfly-like singular attractors are located in the global attractive set only. This result is applied to the chaos control and chaos synchronization. Some feedback control laws are obtained to guarantee that all the trajectories of the Lorenz systems track a periodic solution, or globally stabilize an unstable (or locally stable but not globally asymptotically stable) equilibrium. Further, some new global exponential chaos synchronization results are presented. Our new method and the new results are expected to be applied in real secure communication systems.

关键词： Lorenz chaotic system global attractive set positive invariant set globally exponential tracking globally exponential synchronization.

Epithermal Ageing Mechanism of Gussasphalt

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Journal of Wuhan University of technology(Materials science) 2009年第3期24卷 466-470页

作者：郝增恒 school of Traffic science and Engineering Harbin Institute of Technology Chongqing Communications Research and Design Instituts

The normal asphalt index test, DSR test, FTIR and the GPC distribution analysis of molecular weight on the extraction and recovery of asphalt of the gussasphalt, SMA extraction and recovery of asphalt and the rotary-thin-film-oven-aged asphalt above 2.0 ℃ were introduced. The results indicate the rutting factor and fatigue factor of the extraction and recovery of asphalt of the gussasphalt are greatly improved, and an obvious absorption peak of carbonyl and a further decrease of the SBS molecular weight of the gussasphalt are found.

关键词： gussasphalt epithermal ageing rheolagical performance fourier transforms infrared spectroscopy gel permeation chromatography

Second-order consensus in networks of dynamic agents with communication time-delays

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Journal of Systems Engineering and Electronics 2010年第1期21卷 88-94页

作者： Bo Yang1,2. Huajing Fang3. and Hua Wang4.1. school of Navigation, Wuhan University of {3., Wuhan 4.0063. P. R. China 2. Wuhan Second Ship Design and Research {2., Wuhan 4.0064. P. R. China 3. Department of Control {3. and Engineering, Huazhong University of {3. and {3., Wuhan 4.0074. P. R. China 4. Department of Aerospace and Mechanical Engineering, Boston University, Boston MA02.15, USA school of Navigation Wuhan University of Technology Wuhan 430063 P. R. China Wuhan Second Ship Design and Research institute Wuhan 430064 E R. China Department of Control science and Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China Department of Aerospace and Mechanical Engineering Boston University Boston MA02215 USA

This paper proposes second-order consensus protocols with time-delays and gives the measure of the robustness of the protocols to the time-delay existing in the network of agents with second-order dynamics. By employing a frequency domain method, it is proven that the information states and their time derivatives of all the agents in the network achieve consensus asymptotically, respectively, for appropriate communication timedelay if the topology of weighted network is connected. Particularly, a tight upper bound on the communication time-delay that can be tolerated in the dynamic network is found. The consensus protocols are distributed in the sense that each agent only needs information from its neighboring agents, which reduces the complexity of connections between neighboring agents significantly. Numerical simulation results are provided to demonstrate the effectiveness and the sharpness of the theoretical results for second-order consensus in networks in the presence of communication time-delays.

关键词： second-order consensus protocols dynamic networks algebraic graph theory frequency domain analysis com-munication constraints.

HCWCI/Carbon Steel Bimetal Liner by Liquid-Liquid Compound Lost Foam Casting

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Journal of Iron and Steel Research International 2012年第10期19卷 13-19页

作者： XIAO Xiao-feng1,2. YE Sheng-ping2. YIN Wei-xin3. XUE Qiong4.(1. {3. of Mechanical Engineering and Automation, Wuhan Textile University, Wuhan 4.0073. Hubei, China 2. State Key Laboratory of Material Processing and Die and Mould {4., Huazhong University of {2. and {4., Wuhan 4.0074. Hubei, China 3. Wuhan Zhike Abrasive-Resistant Material {2. and {4. Development Co Ltd, Wuhan 4.0073. Hubei, China 4. College of {2., Wuhan University of {4., Wuhan 4.0079, Hubei, China) [a] school of Mechanical Engineering and Automation Wuhan Textile University Wuhan 430073 Hubei China [b] State Key Laboratory of Material Processing and Die and Mould technology Huazhong University of Science and Technology Wuhan 430074 Hubei China [c] Wuhan Zhike Abrasive-Resistant Material science and technology Development Co Ltd Wuhan 430073 Hubei China [d] College of science Wuhan University of Technology Wuhan 430079 Hubei China

Impact, friction and corrosion from the grinding balls and the grinding medium during the mineral processing result in liner breakage. Liner, made from Hadfield steel or alloyed steel, could not have served in wet grinding environment for more than ten months. Composite liner, made from HCWCI (high Cr white cast iron) and carbon steel, has been developed successfully with liquid-liquid composing process based on LFC (lost foam casting). The microstructure of composite was analyzed with optical microscope, SEM (scanning electron microscope)/EDX energy-dispersive X-ray and XRD (X-ray diffraction). According to micrograph, the combination region of two metals was staggered like dogtooth, no mixtures occurred between two liquid metals, and its interface presented excellent metallurgical bonding state. The results of mechanical property test show that, the hardness of HRC, the fracture toughness, and the bending strength are more than 61, 16.5 J/cm2.and 1 600 MPa, respectively. Comparison between liners made from bimetal composite and alloyed steel has also been investigated in industrial hematite ball mill. The results of eight months test in wet grinding environment prove that the service life of bimetal composite liner is three times as long as that of one made from alloyed steel.

关键词： composite liner bimetal liquid-liquid compound composite interface lost foam casting high Cr white cast iron

Visualization of protein RecR in Escherichia coli by fluorescent labelling

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Progress in Natural science:Materials International 2009年第11期19卷 1545-1551页

作者： Jiefang Qiu,Xuefeng Pan~* school of life {2.,Beijing {3. of {4.,Beijing 100081,China [a]school of life {2. Beijing Institute of Technology Beijing 100081 China

RecR protein,a functional equivalent of Rad52.in eukaryotes,plays a critical role in the RecF pathway of homologous recombination in Escherichia *** constructing and expressing the recR-yfp hybrid gene,the distribution of the RecR-YFP fusion protein was visualized in *** by fluorescent *** results showed that RecR proteins can be localized predominantly in the nucleoid region of *** measuring the UV resistance of a recR mutant carrying the recR-yfp gene in the plasmid,the expressed RecR-YFP was found to be functional in improving the UV resistance of the recR deficiency strain.

关键词： RecR YFP DNA Repair Homologous recombination E.coli

The mathematical model of wetting angle of heterogeneous nucleation

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science China(Technological sciences) 2004年第4期47卷 391-397页

作者： HUANG Cheng1, SONG Bo1, MAO Jinghong2.& ZHAO Pei3.1. school of Metallurgical and Ecological Engineering, University of science and {2. Beijing, Beijing 100083. China 2. school of Material science, University of science and {2. Beijing, Beijing 100083. China 3. Central Iron and Steel Research institute, Beijing 100081, China 1. school of Metallurgical and Ecological Engineering University of Science and Technology Beijing 100083 Beijing China 2. school of Material science University of Science and Technology Beijing 100083 Beijing China 3. Central Iron and Steel Research institute 100081 Beijing China

The heterogeneous nucleation has been analyzed in terms of the thermodynamic theory, and the mathematical model of wetting angle of heterogeneous nucleation has been developed based on the dynamic requirements of hetero- and homogeneous nucleation. With the wetting angel model, the wetting angles of different catalysts in liquid iron have been calculated. The result shows that the wetting angle of most catalysts is smaller than 4., and the value of f() is far less than 1. The wetting angles of TiN, TiC and RE2.3.are smaller, while the wetting angle of MnO is bigger among the ordinary nucleation catalysts. The wetting angles calculated by this model are in agreement with the results of other research work.

关键词： heterogeneous nucleation, mathematical model, wetting angle, undercooling.