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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 2.31. school of Information Engineering, Zhejiang Forestry College, Hangzhou 311300, Zhejiang, China 2. Institute of Computing Technology, chinese {2. of sciences, beijing 100080, China 3. graduate school of the chinese academy of sciences, beijing 100039, China school of Information Engineering Zhejiang Forestry College Hangzhou Zhejiang China Institute of Computing Technology Chinese Academy of Sciences Beijing China graduate school of the chinese academy of sciences Beijing 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

Effect of concentration on surfactant micelle shapes——A molecular dynamics study

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Science China Chemistry 2005年第5期48卷 470-475页

作者： GAO Jian1,2. GE Wei1 & LI Jinghai1 1. Multiphase Reaction Laboratory, Institute of Process Engineering, chinese academy of {2., beijing 100080, China 2. graduate school of the chinese academy of sciences, beijing 100085, China Multiphase Reaction Laboratory Institute of Process Engineering Chinese Academy of Sciences Beijing China graduate school of the chinese academy of sciences Beijing China

Many aspects of the behavior of surfactants have not been well understood due to the coupling of many different mechanisms. Computer simulation is, therefore, attractive in the sense that it can explore the effect of different mechanisms separately. In this paper, the shapes, structures and sizes of sodium dodecylbenzenesulfonate (SDBS) micelles under different con-centrations in an oil/water mixture were studied via molecular dynamics (MD) simulations using a simplified atomistic model which basically maintains the hydrophile and lipophile properties of the surfactant molecules. Above the critical micellar concentration (cmc), surfactant molecules ag-gregate spontaneously to form a wide variety of assemblies, from spherical to rodlike, wormlike and bilayer micelles. Changes in their ratios of the principle moments of inertia (g1/g3, g2.g3) in-dicated the transition of micelle shapes at different concentrations. The aggregation number of micelle is found to have a power-law dependence on surfactant concentration.

关键词： surfactant, MD simulation, sodium dodecylbenzenesulfonate, micelle shape.

Trend of urban system structure under the restriction of water and land resources in Xinjiang

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chinese Science Bulletin 2006年第A1期51卷 179-188页

作者： ZHANG Xiaolei & LEIJun Xinjiang Institute of Ecology and Geography, chinese academy of {2., Urumqi 830011, China Institute of Geographical Science and Natural Resources Research, chinese academy of {2., beijing 100101, China graduate school, chinese academy of {2.,{12., China Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi China Institute of Geographical Science and Natural Resources Research Chinese Academy of Sciences Beijing China graduate school Chinese Academy of Sciences Beijing China

根据在 Xinjiang 影响城市的开发和城市的系统结构的水和陆地资源上的研究，这篇论文分析利用地位和城市的水资源的缺乏。城市的水资源的消费和浪费在一个增加趋势，这被考虑。然而，在 Xinjiang 的大多数城市和镇在水资源的缺乏水资源... 详细信息

根据在 Xinjiang 影响城市的开发和城市的系统结构的水和陆地资源上的研究，这篇论文分析利用地位和城市的水资源的缺乏。城市的水资源的消费和浪费在一个增加趋势，这被考虑。然而，在 Xinjiang 的大多数城市和镇在水资源的缺乏水资源的废物是严肃的，特别在小镇上。megapolis 和中等城市的发展被有限陆地资源显然限制。尽管有扩展小城市和镇的相对大的空格，水和陆地资源的输出好处是低的。为了完成城市的系统的顺序的扩大，在 Xinjiang 组织，在都市化的快速的发展拿一个圆和三条带和节俭资源的策略的城市的空间发展模式被建议。

关键词：城镇体系结构水资源土地资源供水能力新疆

Novel gaseous transient species:generation and characterization

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Science China Chemistry 2007年第2期50卷 145-169页

作者： ZENG XiaoQing1,2.& WANG DianXun11 State Key Laboratory for Structural Chemistry of Unstable and Stable Species,Institute of Chemistry,chinese academy of Sci-ences,{2. 100080,China 2.graduate school of chinese academy of sciences,{2. 100039,China State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing China graduate school of {2. academy of sciences Beijing China

Due to special properties of transient species, such as short-lived, unstable, reactive, and even explosive, the generation and subsequent characterization is a great challenge for experimental chemists. In our laboratory, systematic researches have been carried out to investigate novel transient species: reactive halogen species (RHS), short-lived free radicals, and metastable pseudohalogen compounds, based on the successive technical improvements on the Hel Photoelectron spectroscopy (PES). In this review, the topic mainly focuses on innovative methods of generating novel transient species, and subsequent geometric and electronic structure characterizations of these species combined with quantum chemical calculations.

关键词： reactive halogen species radicals pseudohalogen compounds Hel Photoelectron Spectroscopy (PES) quantum chemical calculations

Representation of microscale ocean wavenumber spectrum correct to the second order

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Science China Earth sciences 2005年第4期48卷 549-554页

作者： YUAN Yeli2.& HUA Feng1,2.3 1. Institute of Oceanology, chinese academy of {2., Qingdao 2.6071, China 2. Key Laboratory of Marine Science and Numerical Modeling, State Oceanic Administration, Qingdao 2.6061, China 3. graduate school of the chinese academy of sciences, beijing 100039, China Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration Qingdao China Institute of Oceanology Chinese Academy of Sciences Qingdao China graduate school of the chinese academy of sciences Beijing China

In this paper, the analytical representations of four wave source functions in high-frequency spectrum range are given on the basis of ocean wave theory and dimensional analysis, and the perturbation method is used to solve the governing equations of ocean wave high-frequency spectrum on the basis of the temporally stationary and locally homogeneous scale relations of microscale wave. The microscale ocean wavenumber spectrum correct to the second order has an explicit structure, its first order part represents the equilibrium between dif- ferent source functions, and its second order part represents the contribution of microscale wave propagation.

关键词： temporally stationary and locally homogeneous, source function in high-frequency spectrum range, microscale ocean wavenumber spectrum.

Overexpression of a tobacco small G protein gene NtRop1 causes salt sensitivity and hydrogen peroxide production in transgenic plants

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Science China(Life sciences) 2008年第5期51卷 383-390页

作者： CAO YangRong1,2. LI ZhiGang1,2. CHEN Tao1,2. ZHANG ZhiGang1, ZHANG JinSong1 & CHEN ShouYi1 1 National Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, chinese academy of {2., beijing 100101, China 2.graduate school of chinese academy of {2., beijing 100039, China National Key Lab of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing China graduate school of {2. academy of sciences Beijing China

The small GTPases of Rop/Rho family is central regulators of important cellular processes in plants. Tobacco small G protein gene NtRop1 has been isolated; however, its roles in stress responses were unknown. In the present study, the genomic sequence of NtRop1 was cloned, which has seven exons and six introns, similar to the Rop gene structure from Arabidopsis. The NtRop1 gene was constitutively expressed in the different organs whereas the other six Rop genes from tobacco had differential expression patterns. The expression of the NtRop1 gene was moderately induced by methyl viologen, NaCl, and ACC treatments, but slightly inhibited by ABA treatment, with no significant induction by NAA treatment. The transgenic Arabidopsis plants overexpressing the NtRop1 showed increased salt sensitivity as can be seen from the reduced root growth and elevated relative electrolyte leakage. The hydrogen peroxide production was also promoted in the NtRop1-trangenic plants in comparison with wild type plants. These results imply that the NtRop1 may confer salt sensitivity through activation of H2.2.production during plant response to salt stress.

关键词： small G protein NtRop1 salt sensitive hydrogen peroxide

SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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Science China Earth sciences 2006年第10期49卷 1032-1042页

作者： PENG Touping1,2. WANG Yuejun1, FAN Weiming1, LIU Dunyi3, SHI Yuruo3 & MIAO Laicheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, chinese academy of {2., Guangzhou 510640, China 2. graduate University of chinese academy of {2., beijing 100039, China 3. SHRIMP isotope Laboratory, chinese academy of Geological {2., beijing 100037, China 4. Institute of Geology and Geophysics, chinese academy of {2., beijing 10002., China Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China graduate University of chinese {2. of sciences Beijing China SHRIMP isotope Laboratory Chinese Academy of Geological Sciences Beijing China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02.X-137) and southern (2.JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 2.6Pb/2.8U ages of 2.9.4 ± 3.0 Ma and 2.0.4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02.X-95) from the Manghuai Formation give a weighted mean 2.6Pb/2.8U age of 2.1.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~2.0 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 2.6Pb/2.8U apparent age of 1977±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, Manghuai Formation rhyolite, southern Lancangjiang.

Kinetics and reaction mechanism of phenol hydroxylation catalyzed by La-Cu_4FeAlCO_3

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Science China Chemistry 2005年第6期48卷 530-537页

作者： CHEN Chunxia1,2. XU Chenghua1, FENG Liangrong1, SUO Jishuan1 & QIU Fali1 1. Chengdu Institute of Organic Chemistry, chinese academy of {2., Chengdu 610041, China 2. graduate school of the chinese academy of sciences, beijing 100039, China Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu China graduate school of the chinese academy of sciences Beijing China

The present work synthesizes La-Cu4FeAlCO3 catalyst under microwave irradiation and characterizes its structure using XRD and IR techniques. The results show that the obtained La-Cu4FeAlCO3 has a hydrotalcite structure. In the phenol hydroxylation with H2.2.catalyzed by La-Cu4FeAlCO3, the effects of reaction time and phenol/H2.2.molar ratio on the phenol hy-droxylation, and relationships between the initial hydroxylation rate with concentration of the catalyst, phenol, H2.2.and reaction temperature are also investigated in details. It is shown the phenol conversion can reach 50.09% (mol percent) in the phenol hydroxylation catalyzed by La-Cu4FeAlCO3, under the reaction conditions of the molar ratio of phenol/H2.2.1/2. the amount ratio of phenol/catalyst 2., reaction temperature 343 K, reaction time 12. min, 10 mL distilled water as solvent. Moreover, a kinetic equation of v = k[La ? Cu 4 FeAlCO 3 ][C 6 H 5 OH][H 2.O 2.. and the activation energy of Ea=58.37 kJ/mol are obtained according to the kinetic studies. Due to the fact that the HO-Cu+-OH species are detected in La-Cu4FeAlCO3/H2.2.system by XPS, the new mechanism about the generation of hydroxyl free radicals in the phenol hydroxylation is pro-posed, which is supposed that HO-Cu+-OH species are transition state in this reaction.

关键词： rare earth, hydrotalcite, microwave irradiation, phenol hydroxylation, kinetics, reaction mechanism.

Contributions of phosphatase and microbial activity to internal phosphorus loading and their relation to lake eutrophication

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Science China Earth sciences 2006年第Z1期49卷 102-113页

作者： SONG Chunlei, CAO Xiuyun, LI Jianqiu, LI Qingman, CHEN Guoyuan & ZHOU Yiyong Institute of Hydrobiology, chinese academy of {2., Wuhan 430072. China graduate school of the chinese academy of sciences, beijing 100039, China Institute of Hydrobiology Chinese Academy of Sciences Wuhan China graduate school of the chinese academy of sciences Beijing China

Phosphatase may accelerate the process of lake eutrophication through improving phosphorus bioavailability. This mechanism was studied in three chinese eutrophic shallow lakes (Lake Taihu, Lake Longyang and Lake Lianhua). Phosphatase activity was related to the concentration of soluble reactive phosphorus (SRP) and chlorophyll a. Stability of dissolved phosphatase in reverse micelles may be attributed to molecular size, conformation and active residues of the *** the site with Microcystis bloomed in Lake Taihu, dissolved phosphatase activity was higher and more stable in micelles, SRP concentrations were lower in interstitial water, the contents of different forms of phosphorus and the amounts of aerobic bacteria were lower while respiration efficiency was higher in sediments. Phosphobacteria, both inorganic and organic and other microorganisms were abundant in surface water but rare in sediments. Therefore, internal phosphorus may substantially flux into water column by enzymatic hydrolysis and anaerobic release, together with mobility of bacteria,thereby initiating the bloom. In short, biological mechanism may act in concert with physical and chemical factors to drive the internal phosphorus release and accelerate lake eutrophication.

关键词： dissolved phosphatase, reverse micelle, internal loading, phosphorus form of sediment, microbiology, eutrophication, Microcystis bloom.