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Fluorescence fluctuation spectroscopy and its artifacts:simulations and tests

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Science China(Physics,Mechanics & Astronomy) 2005年第3期48卷 336-344页

作者： MENG Fanbo 1., CHEN Bo 1., LIU Guang 1., DING Jianying 1.& MA Hui 2,1.1. Department of Physics and Key Laboratory of Atomic and Molecular Nano Sciences, Ministry of Educa- tion, Tsinghua University, Beijing 1.0084, China 2. graduate {1. at Shenzhen, Tsinghua University, Shenzhen 51.055, China 1. Department of Physics and Key Laboratory of Atomic and Molecular Nano Sciences Ministry of Education Tsinghua University 100084 Beijing China 2. graduate {1. at Shenzhen Tsinghua University 518055 Shenzhen China

Fluorescence fluctuation spectroscopy (FFS) technique is capable of monitoring changes in concentration, mass, size and structure of fluorescent-labeled bio-molecules in microscopic volume and is suitable for measuring biological interactions in living cells. FFS data may be affected by many experimental factors in complicated biological systems. Using a Monte Carlo approach, we generate fluorescence fluctuation data for different experimental systems. This approach helps to separate the contributions by different experimental factors in a complicated fluorescence fluctuation spectrum. It also helps to validate new theoretical models and new fitting formulations. We describe the algorithm of the simulation program and tests on its statistical performance. The program is then used successfully to study the effects of several experimental factors on FFS detection.

关键词： fluorescence fluctuation spectroscopy, fluorescence correlation spectroscopy, Monte Carlo simulation.

ON EFFECTIVE NON-VANISHING OF WEIL DIVISORS ON ALGEBRAIC SURFACES

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Chinese Annals of Mathematics,Series B 2005年第1期26卷 105-110页

作者： XIEQIHONG graduate{1.ofMathematicalSciences UniversityofTokyo3-8-1KomabaMeguroTokyo153-8914Japan

The author gives a counterexample and some conclusions for effective non-vanishing of Weil divisors on algebraic surfaces.

关键词： Weil divisors Algebraic surfaces Effective non-vanishing

Structures and physical properties of rigid polyurethane foams with water as the sole blowing agent

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Science China Chemistry 2006年第4期49卷 363-370页

作者： LI Xiaobin1.2, CAO Hongbin1.& ZHANG Yi1.1. Institute of Process Engineering, Chinese Academy of Sciences, Beijing 1.0080, China 2. graduate {1. of the Chinese Academy of Sciences, Beijing 1.003., China 1. Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China 2. graduate {1. of the Chinese Academy of Sciences Beijing 100039 China

Rigid polyurethane foams blown by varying water level were prepared in this study. The structures and physical properties of rigid polyurethane foams blown by water were measured with FT-IR, universal testing machine (Instron3.65), scanning electron microscope (SEM) and differential scanning calorimeter (DSC). The results show that polyurea and polybiuret were the typical charac- teristics, and the cream time and gel time were shorter for the fully water blown rigid foams than that for the fully cyclopentane blown foams. The density of foam samples decreased from 45.0 kg/m3.to 27.4 kg/m3.with the increase of water level from 3.pph to 7 pph. Compressive strength exhibited the similar behavior with density. The average cell size of foam samples ranged from 241.μm to 3.6 μm with the increase of water level from 3.pph to 7 pph, respectively. At the same time, poorer dimen- sional stability was encountered with the increase of average cell size due to fast diffusion rate of CO2 out of the foam. The results of thermal analysis show that the glass transition temperature (Tg) shifted to a higher temperature with the increase of isocyanate level when more water was used as chemical blowing agent.

关键词： polyether polyol, polyurethane rigid foam, compressive strength, dimensional stability, cell size, glass transition temperature.

Formal Verification under Unknown Constraints

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Wuhan University Journal of Natural Sciences 2005年第1期10卷 43-46页

作者： LI Guang-hui 1.2,3., LI Xiao-wei 2,3.. school of Information Engineering, Zhejiang Forestry College, Hangzhou 3.1.0}0, Zhejiang, China 2. Institute of Computing Technology, Chinese Academy of Sciences, Beijing 1.0080, China 3. graduate school of the Chinese Academy of Sciences, Beijing 1.003., China school of Information Engineering Zhejiang Forestry College Hangzhou 311300 Zhejiang China

We present a formal method of verifying designs with unknown constraints (e.g., black boxes) using Boolean satisfiability (SAT). This method is based on a new encoding scheme of unknown constraints, and solves the corresponding conjunctive normal form (CNF) ***,this method can avoid the potential memory explosion, which the binary decision diagram (BDD) based techniques maybe suffer from, thus it has the capacity of verifying large designs. Experimental results demonstrate the efficiency and feasibility of the proposed method.

关键词： formal verification unknown constraints black box Boolean satisfiability Boolean comparison

Improvement of different source function expressions in SWAN model for the Bohai Sea

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Progress in Natural Science:Materials International 2005年第8期15卷 720-724页

作者： YIN Baoshu1., YANG Dezhou1. SHA Rina 1.2 and CHENG Minghua1.1. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071. China 2. graduate {1. of the Chinese Academy of Sciences, Beijing 1.003., China) Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China. graduate {1. of the Chinese Academy of Sciences Beijing 100039 China

The simulating wave nearshore （SWAN） wave model has been widely used in coastal areas, lakes and estuaries. However, we found a poor agreement between modeling results and measurements in analyzing the chosen four typical cases when we used the default parameters of the source function formulas of the SWAN to make wave simulation for the Bohai Sea. Also, it was found that at the same wind process the simulated results of two wind generation expressions （Komen, Janssen） demonstrated a large difference. Further study showed that the proportionality coefficient α in linear growth term of wave growth source function plays an unperceived role in the process of wave development. Based on experiments and analysis, we thought that the coefficient α should change rather than be a constant. Therefore, the coefficient α changing with the variation of friction velocity U*was introduced into the linear growth term of wave growth source function. Four weather processes were adopted to validate the improvement in the linear growth term. The results from the improved coefficient α agree much better with the measurements than those from the default constant coefficient α. Furthermore, the large differences of results between Komen wind generation expression and Janssen wind generation expression were eliminated. We also experimented with the four weather processes to test the new white-capping mechanisms based on the cumulative steepness method. It was found that the parameters of the new white-capping mechanisms are not suitable for the Bohai Sea, but Alkyon's white-capping mechanisms can be applicable to the Bohai Sea after amendments, demonstrating that this improvement of parameter α can improve the simulated results of the Bohai Sea.

关键词： waves SWAN model wave growth source function new proportionality coefficient formula.

Algebraically explicit analytical solu-tions for the unsteady non-Newtonian swirling flow in an annular pipe

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Science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 396-400页

作者： CAI Ruixian1.& GOU Chenhua1.2 1. Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 1.0080, China 2. graduate {1., Chinese Academy of Sciences, Beijing 1.0080, China 1. Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100080 China 2. graduate {1. Chinese Academy of Sciences Beijing 100080 China

This paper presents two algebraically explicit analytical solutions for the incompressible unsteady rotational flow of Oldroyd-B type in an annular pipe. The first solution is derived with the common method of separation of variables. The second one is deduced with the method of separation of variables with addition developed in recent years. The first analytical solution is of clear physical meaning and both of them are fairly simple and valuable for the newly developing computational fluid dynamics. They can be used as the benchmark solutions to verify the applicability of the existing numerical computational methods and to inspire new differencing schemes, grid generation ways, etc. Moreover, a steady solution for the generalized second grade rheologic fluid flow is also presented. The correctness of these solutions can be easily proven by substituting them into the original governing equation.

关键词： analytical solution, Oldroyd-B type fluid, swirling flow, non-Newtonian.

A subsurface runoff parameterization with water storage and recharge based on the Boussinesq-Storage Equation for a Land Surface Model

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Science China Earth Sciences 2006年第6期49卷 622-631页

作者： TIAN Xiangjun1.2, XIE Zhenghui1. ZHANG Shenglei1.& LIANG Miaoling1.1. LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 1.0029, China 2. graduate {1. of the Chinese Academy of Sciences, Beijing 1.003., China 1. LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. graduate {1. of the Chinese Academy of Sciences Beijing 100039 China

Subsurface runoff in a land surface model is usually parameterized as a single-valued function of total storage in a basin aquifer reservoir. This kind of parameterization is often sin-gle-valued function of storage-discharge under a steady or “quasi-steady” state, which cannot rep-resent the influence of aquifer recharge on subsurface runoff generation. In this paper, a new sub-surface runoff parameterization with water storage and recharge based on the Boussinesq-storage equation is developed. This model is validated by a subsurface flow separation algorithm for an ex-ample river basin, which shows that the new model can simulate the subsurface flow reasonably.

关键词： Zsubsurface runoff parameterization Boussinesq-storage equation waterstorage and recharge

Study on the coating of nano-scale SiO_2 film on the surface of nanocrystalline Mg-Al layered double hydroxides

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Science China Chemistry 2005年第2期48卷 107-114页

作者： ZHANG Zejiang1.2,3. MEI Xiujuan2, XU Chenghua1.& QIU Fali1.1. Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 61.041. China 2. Sichuan Fire Research Institute of Public Security Ministry, Chengdu 61.83., China 3. graduate school of the Chinese Academy of Sciences, Beijing 1.003., China Correspondence should be addressed to Zhang Zejiang (email: zzjzzjzz@***) 1. Chengdu Institute of Organic Chemistry Chinese Academy of Sciences 610041 Chengdu China 2. Sichuan Fire Research Institute of Public Security Ministry 611830 Chengdu China 3. {1. school of the Chinese Academy of Sciences 100039 Beijing China

The coating process of a nano-scale SiO2 film on the nanocrystalline Mg-Al layered double hydroxides via a sol-gel process was investigated. The uniform and dense SiO2film with a thickness of about 5 nm on the nano-LDHs particles was characterized by the solubility test in the dilute HNO3.or HCl acid, TEM and FT-IR, XRD, TG and DSC. The chemical shifts of binding en- ergies of Al 2p, Mg 2p, Si 2s and O 1. on the coated particles indicate that the coating of the SiO2 nano-film on the surface of the nano-LDHs proceeds through the formation of Mg-O-Si and Al-O-Si bonds. The thermal analysis shows that both the SiO2-coated nano-LDHs and the nano-LDHs have a similar mass loss process, in which there are three obvious stages of mass loss in the temperature range of 40—700℃. Furthermore, the more the coatedamount of SiO2on the surface of the nano-LDHs is, the less the mass loss of the samples is at 700℃.The nano- LDHs have two obvious endothermic peaks at 244.67℃ and 43..1.0}, whose corresponding heat absorption capacities are 41..28 J/g and 3.6.3. J/g, respectively. In contrast, the coated nano-LDHs have only one endothermic peak at 243.60℃ with a heat absorption capacity of 221.25 J/g.

关键词： layered double hydroxides, nanocrystalline, silica, coating.

Characteristics and geological significance of olivine xenocrysts in Cenozoic volcanic rocks from western Qinling

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Progress in Natural Science:Materials International 2006年第12期16卷 1300-1306页

作者： SU Benxun~ 1.2 **, ZHANG Hongfu~1. XIAO Yan~ 1.2 and ZHAO Xinmiao~ 1.2 (1. State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 1.0029, China 2. graduate {1. of Chinese Academy of Sciences, Beijing 1.003., China) [a]State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China [b]graduate {1. of Chinese Academy of Sciences Beijing China

Cenozoic volcanic rocks from the Haoti, Dangchang County of the western Qinling Mountains, contain a few clearly-zoned olivines. These olivines are relatively big in grain sizes and usually have cracks or broken features. Their cores have similar compositions （Mg#=90.4-91.0） to those for the peridotitic xenoliths entrained in host volcanic rocks and their rims are close to the compositions of olivine phenocrysts （Mg#=85.5-81.9）. The CaO contents in these zoned olivines are lower than 0.1.. These features demonstrate that the clearly-zoned olivines are xenocrysts and disaggregated from mantle peridotites. The zoned texture was the result of the interaction between the olivine and host magma. Available data show that the volcanic rocks would have been derived from the mantle source metasomatized by subducted hydrathermally-altered oceanic crust. The formation of these Cenozoic volcanic rocks was perhaps related to the rapid uplift of the Tibetan Plateau.

关键词： Western Qinling Dangchang Haoti Cenozoic volcanic rocks olivine xenocrysts zoned texture.