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Utilization of a spiropyran derivative in a polymeric film optode for selective fluorescent sensing of zinc ion

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Science china Chemistry 2006年第3期49卷 246-255页

作者： ZHANG Ying1, SHAO Na1, YANG Ronghua1, LI Ke’an1, LIU Feng1, CHAN Winghong2.& MO Tian2.1. College of Chemistry and Molecular engineering, Peking university, Beijing 100871,{2. 2. department of Chemistry, Hong Kong Baptist university, Hong Kong,{2. 1. College of Chemistry and Molecular engineering Peking University Beijing 100871 China 2. department of Chemistry Hong Kong Baptist University Hong Kong China

A new spiropyran derivative was synthesized and first utilized in a polymericfilm-based optical sensor for zinc ion. Spiropyrans, combining the characteristics of metal bindingand signal transduction, show potential function in the design of optical chemical sensors(optodes) toward metal ions. When embedded in a plasticized poly (vinyl chloride) (PVC) membrane,the newly synthesized spiropyran derivative 1 exhibits obvious fluorescence enhancement at 630 nm inthe presence of zinc ion in aqueous solution. With the optimum condition described, the optodemembrane responds to zinc ion over a dynamic range of 4.94x10^(-7) to 4.15x10^(-4)mol·L^(-1), witha detection limit of 1.51x10^(-7) mol·L^(-1). The membrane not only displays excellentphotostability, reproducibility and reversibility, but also exhibits high selectivity toward zincion over transition metal ions including Hg^(2.), Cd^(2.), Pb^(2.), Cu^(2.), Fe^(3+) and commoncationic ions presented in the physiological fluids.

关键词： spiropyran, sensor, PVC membrane, zinc ion, fluorescent spectroscopy.

A land surface model incorporated with soil freeze/thaw and its application in GAME/Tibet

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Science china Earth Sciences 2006年第12期49卷 1311-1322页

作者： HU Heping1, YE Baisheng2. ZHOU Yuhua3 & TIAN Fuqiang1 1. department of Hydraulic engineering, Tsinghua {2., Beijing 100084, china 2. Cold and Arid Regions Environmental and engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, china 3. department of civil engineering, Massachusetts Institute of Technology, USA 1. department of Hydraulic engineering Tsinghua University Beijing 100084 China 2. Cold and Arid Regions Environmental and engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 3. department of civil {2. Massachusetts Institute of Technology USA

Land surface process is of great importance in global climate change, moisture and heat exchange in the interface of the earth and atmosphere, human impacts on the environment and eco- system, etc. Soil freeze/thaw plays an important role in cold land surface processes. In this work the diurnal freeze/thaw effects on energy partition in the context of GAME/Tibet are studied. A sophisti- cated land surface model is developed, the particular aspect of which is its physical consideration of soil freeze/thaw and vapor flux. The simultaneous water and heat transfer soil sub-model not only reflects the water flow from unfrozen zone to frozen fringe in freezing/thawing soil, but also demon- strates the change of moisture and temperature field induced by vapor flux from high temperature zone to low temperature zone, which makes the model applicable for various circumstances. The modified Picard numerical method is employed to help with the water balance and convergence of the numerical scheme. Finally, the model is applied to analyze the diurnal energy and water cycle char- acteristics over the Tibetan Plateau using the Game/Tibet datasets observed in May and July of 1998. Heat and energy transfer simulation shows that: (i) There exists a negative feedback mechanism between soil freeze/thaw and soil temperature/ground heat flux; (ii) during freezing period all three heat fluxes do not vary apparently, in spite of the fact that the negative soil temperature is higher than that not considering soil freeze; (iii) during thawing period, ground heat flux increases, and sensible heat flux decreases, but latent heat flux does not change much; and (iv) during freezing period, soil temperature decreases, though ground heat flux increases.

关键词： land surface model,soil freeze/thaw,GAME/Tibet,simultaneous liquid,vapor and heat transfer.

THREE-DIMENSIONAL SIMULATION OF MEANDERING RIVER BASED ON 3-D RNG k-ε TURBULENCE MODEL

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Journal of Hydrodynamics 2008年第4期20卷 448-455页

作者： ZHANG Ming-liang SHEN Yong-ming State Key Laboratory of Coastal and Offshore engineering Dalian University of Technology Dalian 116024China department of civil and Structural {2. The Hong Kong Polytechnic University Hong Kong China

A 3-D numerical model for calculating flow in non-curvilinear coordinates was established in this article. The flow was simulated by solving the full Reynolds-averaged Navier-Stokes equations with the RNG κ-ε turbulence model. In the horizontal x-y-plane, a boundary-fitted curvilinear co-ordinate system was adopted, while in the vertical direction, a σ co-ordinate transformation was used to represent the free surface and bed topography. The water level was determined by solving the 2.D Poisson equation derived from 2.D depth averaged momentum equations. The finite-volume method was used to discretize the equations and the SIMPLEC algorithm was applied to acquire the coupling of velocity and pressure. This model was applied to simulate the meandering channels and natural rivers, and the water levels and the velocities for all sections were given. By contrasting and analyzing, the agreement with measurements is generally good. The feasibility studies of simulating flow of the natural fiver have been conducted to demonstrate its applicability to hydraulic engineering research.

关键词： non-orthogonal curvilinear coordinates RNG κ-ε turbulence model 2.D Poisson equation SIMPLEC algorithm depth averaged equation

Rank of loop, constraint degree of path, coupling degree of graph and their application

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Progress in Natural Science:Materials International 2005年第2期15卷 79-85页

作者： YANG Tingli1*, LUO Yufeng2. ZHANG Ce3 and YAO Fanghua1(1. SINOPIC Jinling Petrochemical Corp., Nanjing 2.0037, china 2. department of Mechanical {2., Nanchang university, Nanchang 33002., china 3. department of Mechanical {2., Tianjin university, Tianjin 300072. china) SINOPIC Jinling Petrochemical Corp. Nanjing 210037 China. department of Mechanical engineering Nanchang University Nanchang 330029 China. department of Mechanical engineering Tiánjin University Tianjin 300072 China

Some new concepts (rank of a loop, degree of freedom of a graph, path unit and ordered path arrangement, constraint degree of path, coupling degree of a graph, basic graph, etc.), formulas, and algorithms, are proposed in this paper. Based on these concepts, a new systematic theory and practical method for the design of topological structure, kinematics and dynamics of mechanical systems is established. Some conjectures and problems needed to be researched are also put forward. The concepts, formulae and algorithms presented in this paper will find wide potential applications.

关键词： rank of loop degree of freedom of graph constraint degree of path coupling degree of graph

Characteristics of vertical ozone distribution in the lower troposphere in the Yangtze River Delta at Lin'an in the spring of 2.01

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Science china Earth Sciences 2005年第9期48卷 1519-1528页

作者： ZHENG Xiangdong1, CHAN Chuenyu2. CUI Hong2. QIN Yu3, CHAN Loyan2. ZHENG Yongguang3 & LEE Yusiang2.1. Chinese Academy of Meteorological Sciences, Beijing 100081, china 2. department of {2. and Structural engineering, Hong Kong Polytechnic university, Hung Hom, Hong Kong, china 3. department of Atmospheric Sciences, Peking university, Beijing 100871, china 1. Chinese Academy of Meteorological Sciences 100081 Beijing China 2. department of civil and Structural {2. Hong Kong Polytechnic University Hung Hom Hong Kong China 3. department of Atmospheric Sciences Peking University 100871 Beijing China

We analyzed vertical distributions of ozone (O3) in the lower troposphere (< 5 km above ground) at Lin’an (119.75°E, 30.30°N), Zhejiang Province using electrochemical concen- tration cell (ECC) ozonesonde data obta... 详细信息

We analyzed vertical distributions of ozone (O3) in the lower troposphere (2. to April 13, 2.01. The results showed that the vertical O3 distributions are controlled by metrological conditions and the char- acteristics of O3 profiles are related to those of wet bulb potential temperature and wind field. O3 below 2.km showed that the strongest variability and enhanced O3 mixing ratios were associated with easterly winds that blow pollutants from the upwind source region of the Yangtze River Delta (YRD) region. Vertical O3 profiles below 5 km can be grouped into 5 categories: (1) peak mixing ratio type, (2. well-mixed type, (3) layered-structure type, (4) episodic pollution type and (5) alti- tudinal increasing type. Vertical distributions of O3 affected by regional transport of polluted air masses were investigated. Transport of polluted air from high latitudes of northern china, ac- companying subsiding motion of air and stagnant atmospheric conditions are important factors that lead to high mixing ratios of O3 at Lin’an. The stagnant atmospheric conditions associated with a continental high pressure system and pollution plume transported from the YRD and cen- tral-eastern china also lead to regional accumulation of O3 and high O3 mixing ratio at Lin’an. Long-range transport of O3 and pollutants from the Pearl River Delta in South china and in-situ O3 formation also resulted in elevated O3 mixing ratios at around 1 km altitudes and layered O3 distribution in the lower troposphere.

关键词： vertical ozone distribution, lower troposphere, Yangtze River Delta, Lin'an.

Recent development in structural design and optimization

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Acta Mechanica Sinica 2010年第6期26卷 807-823页

作者： Xu Guo·Geng-Dong Cheng State Key Laboratory of Structural Analysis for Industrial Equipment,department of engineering Mechanics,{2. university of Technology, dalian 11602.,china State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering Mechanics Dalian University of Technology Dalian China

With the fast development of computational mechanics and the capacity as well as the speed of modern computers,simulation-based structural optimization has become an indispensable tool in the design process of competitive *** paper presents a brief description of the current status of structural optimization by reviewing some significant progress made in the last *** research topics are also *** entire literatures of the field are not covered due to the limitation of the length of *** scope of this review is limited and closely related to the authors＇ own research interests.

关键词： Structural optimization Multi-scale Uncertainty Multi-physics Software

MINIMIZING A LINEAR FRACTIONAL FUNCTION SUBJECT TO A SYSTEM OF SUP-T EQUATIONS WITH A CONTINUOUS ARCHIMEDEAN TRIANGULAR NORM

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Journal of Systems Science & Complexity 2009年第1期22卷 49-62页

作者： Pingke LI Edward P.Fitts department of Industrial and Systems engineering,North Carolina State {2.,Raleigh,NC 2.695-7906,US Shu-Cherng FANG Edward P.Fitts department of Industrial and Systems engineering,North Carolina State {2.,Raleigh,NC 2.695-7906,USA department of Mathematical Sciences,Tsinghua {2.,Beijing 100084,china College of Management,dalian {2. of Technology,dalian {12.,china. department of Industrial and Systems engineering North Carolina State University

This paper shows that the problem of minimizing a linear fractional function subject to asystem of sup-T equations with a continuous Archimedean triangular norm T can be reduced to a 0-1linear fractional optimization problem in polynomial ***,parametrization techniques,e.g.,Dinkelbach's algorithm,can be applied by solving a classical set covering problem in each *** reduction can also be performed on the sup-T equation constrained optimization problems withan objective function being monotone in each variable *** method could be extended aswell to the case in which the triangular norm is non-Archimedean.

关键词： Fractional optimization fuzzy relational equations triangular norms.

Experimental study of human-induced effects on floor slab of an ancient Tibetan structure

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Earthquake engineering and engineering Vibration 2012年第4期11卷 513-523页

作者： Yang Na Guo Ting S.S. Law School of civil engineering Beijing Jiaotong University civil and Structural engineering {2. Hong Kong Polytechnic University

With the opening of ancient Tibetan structures to visitors worldwide, human load has become the principal live load on these structures. This project studies the properties of the floor structure of an ancient Tibetan building and its behavior under human-induced load effects. Tests were conducted with static and dynamic crowd load, including stepping and jogging by people at a fixed position. The tests show that the floor structure does not behave as a continuous slab. It takes the load from local areas with minimal load transference properties. The acceleration response shows significant peaks when the footstep frequency is close to the natural frequency of the s~＇ucture, but the human jogging excitation frequency does not have any obvious effect on the structural response. The elastic modulus of the Agatu material is estimated to be close to zero from the measured natural frequency of the slab. The Agatu material is concluded to be a discrete compacted material with insignificant contribution to the structural rigidity of the floor slab.

关键词： ancient Tibetan structure crowd load static dynamic floor slab Agatu elastic modulus

Effect of Activator and Curing Mode on Fly Ash-based Geopolymers

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Journal of Wuhan university of Technology(Materials Science) 2009年第5期24卷 711-715页

作者：侯云芬 Institute of civil engineering and Traffic Beijing Institute of Civil Engineering and Architecture department of Material China University of Mining and Technology

The influences of concentration and modulus of sodium silicate solution and curing mode on the phase composition, microstructure and strength development in the geopolymers prepared using Class F fly ash were investigated. X-ray diffraction （XRD）, Fourier transform infrared spec-troscopy （FTIR） and MAS NMR were utilized. Results show that the compressive strength increases as sodium silicate solution modulus increases, but when modulus exceeds 1.4, the compressive strength decreases, and it decreases markedly while the modulus is greater than 2.0. The compressive strength was improved by the increase of sodium silicate solution concentration. When the concentration is 32., the compressive strength reaches the maximum, then it reduces as concentration increasing. Elevated temperature can increase the strength of samples that synthesized from sodium silicate solution with 32. concentration and modulus 1.2. Compared to the strength of the sample cured at 50 ℃, the strength of the samples cured at 65 ℃ and 80 ℃ are higher at 1 d and 3 d, but the same at 7 d. At high temperature, prolonged curing time will decrease the strength. Long precuring at room temperature before application of heat is beneficial for strength development, and there is about 50% increase in strength of the samples cured at 1 d precuring and 2.d elevated temperature as compared to the strengths of the samples cured for 3 d at elevated temperatures or cured for 2. d at room temperature. The main product of reaction in the geopolymeric material is amorphous alkali aluminosilicate gel.

关键词： geopolymers fly ash activator elevated temperature