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Structure of augmentation quotients of finite homocyclic abelian groups

The 4th Joint china/Japan Chemical Engineering Symposium

作者： Gao Junhu a b Zhao Luqi Cui Fumei Hao Xu Xu yuanyuan Cao Liren * Li yongwang a Institute of Coal chemistry chinese academy of sciences Taiyuan Shanxi 030001 p r china b graduate university of the chinese academy of sciences beijing 100039 p. r. china

A kinetic study of noncatalytic partial oxidation of methane （NCpOM） using the GrI, NIST, Alexander andLeeds mechanisms of CH4 Oxidation were done by Jianning zhu and Dongke Zhang. It concluded three importantinformation:1. Two distinct reaction zones exist during NCpOM process, i.e. a fast oxidation zone and a slow conversion zone.2. High O2/CH4 ratios can significantly accelerate all reactions and offer much high reacting Temperature.3. High reacting Temperature can greatly reduce the residence time requires to achieve a desires syngas yield. From these kinetic modeling results, a new kind reactor was introduced here and investigated byThermodynamic Equilibrium method. According to 1 and 2, reactor is divided into two zones: one is CH4combusting zone, the other is reforming reactions zone. At the same time, CH4 feed is also divided into two flows:one at the combusting zone, the other at the reforming zone. According to 3, a reversed flow-preheating scheme isapplied to reforming reactions zone to preheat the flow of CH4 in order to increase the temperature of reformingzone. Two regenerate zones filled with inert stuffing, which cool down the products gas or heat up the CH4 flowentering the reforming zone, connect to the oppose sides of reforming zone. The whole reactor is named byAutothermal reversed flow reactor （ArFr）, which is shown schematically in Fig. 1. In this paper, total Gibbs free energy minimization method is used to simulate the chemistry reactionsthermodynamic equilibrium in adiabatic situation. The reacting characteristics of the NCpOM process are firstlyinvestigated in a fixed reactor for preparing the optimal operating conditions for the thermodynamic simulation ofArFr. CO2 or Steam adding to the NCpOM is also studied. Then a ArFr model is established and simulated indetails. Thirdly, a ArFr with outer Heat exchangers is considered. Finally, the characteristics of the Fixed bed,the ArFr with or without CO2 and Steam adding, the ArFr with outer Heat

关键词： Noncatalytic partial Oxidation of Methane Autothermal reversed Flow reactor Syngas Thermodynamic analyses

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Science china Mathematics 2007年第9期50卷 1280-1288页

作者： Guo-ping TANG School of Mathematical sciences,graduate university of chinese academy of sciences,beijing 100049,china School of Mathematical sciences Graduate University of Chinese Academy of Sciences Beijing China

Let G be a finite abelian group and its Sylow p-subgroup a direct product of copies of a cyclic group of order p r , i.e., a finite homocyclic abelian group. Let Δ n (G) denote the n-th power of the augmentation ideal Δ(G) of the integral group ring ?G. The paper gives an explicit structure of the consecutive quotient group Q n (G) = Δ n (G)/Δ n+1(G) for any natural number n and as a consequence settles a problem of Karpilovsky for this particular class of finite abelian groups.

关键词： integral group ring augmentation ideal consecutive quotient of augmentation ideal 16S34 20C05

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SUSpENDED SEDIMENT TrANSpOrT IN THE OFFSHOrE NEAr YANGTZE ESTUArY

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Journal of Hydrodynamics 2008年第3期20卷 373-381页

作者： CHEN bin WANG Kai Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China graduate university of the chinese academy of sciences Beijing 100039 China

based on the Estuarine, Coastal and Ocean Modeling System with Sediments （ECOMSED） model, a 3-D hydrodynamic-transport numerical model was established for the offshore area near the Yangtze Estuary in the East china Sea .The hydrodynamic module was driven by tide and wind. Sediment module included sediment resuspension, transport and deposition of cohesive and non-cohesive sediment. The settling of cohesive sediment in the water column was modeled as a fimction of aggregation （flocculation） and deposition. The numerical results were compared with observation data for August, 2006. It shows that the sediment concentration reduces gradually from the seashore to the offshore area. Numerical results of concentration time series in the observation stations show two peaks and two valleys, according with the observation data. It is mainly affected by tidal current. The suspended sediment concentration is related to the tidal current during a tidal cycle, and the maximum concentration appears 1 h-4 h after the current maximum velocity has reached.

关键词： Yangtze Estuary sediment concentration sediment transport

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Compositions of heavy minerals in Northeastern china sandlands and provenance analysis

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Science china Earth sciences 2007年第11期50卷 1715-1723页

作者： XIE Jing1,2 & DING ZhongLi1 1 Institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china 2 graduate university of chinese academy of sciences, beijing 100049, china Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China

Sand samples deposited since the Last Glacial Maximum (LGM) from the Hulun buir, Horqin and Otin-dag sandlands were measured for their assemblages of heavy minerals and chemical compositions of detrital garnets and tourmalines. Heavy mineral assemblages of these three sandlands consist mainly of garnet, ilmenite, epidote and minor amphibole and magnetite. Garnets consist mainly of high Mg type-A ones (58% on average), and minor type-b ones. Toumalines are mainly composed of Mg-rich and minor Fe-rich ones. Compared with those of central-southern Mongolia and central Tarim, these three sandlands are derived from the phanerozoic rocks of the Central Asian Orogenic belt and the Archean and paleoprotorozoic basement rocks of the North china Craton. Our results provide direct evidence that the present-day sands may be reworked from LGM ones. Differences of heavy mineral composi-tions occur between the samples of the three sandlands and Taklimakan Desert, indicating that the material of the western arid regions contributes little to the eastern sandlands.

关键词： heavy minerals,provenance,Northeastern china,garnet,tourmaline

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Vertical adaptive radiation in ocean prochlorococcus:Evolutionary implications of the Ch1 b/a ratio from molecular evidence

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progress in Natural Science:Materials International 2009年第11期19卷 1561-1568页

作者： Song Qin~(a,*),Yinchu Wang~(a,b) a Yantai Institute of Coastal Zone research for Sustainable Development,chinese academy of sciences,Yantai 264003,china b graduate university of chinese academy of sciences,beijing 100049,china Yantai Institute of Coastal Zone research for Sustainable Development Chinese Academy of Sciences Yantai 264003 China graduate university of chinese academy of sciences Beijing 100049 China

prochlorococcus is a marine cyanobacterium of global *** ecotypes are adapted to either high-light(HL) or low-light (LL) *** ratio between chlorophyll(Chl) a and b is a distinguishing characteristic of these two ***,how this ratio evolved in prochlorococcus during this ecotype differentiation remains *** analyses reveal that the ancestor of prochlorococcus was typically low-light *** LL ecotype showed a stagnant evolution,and the HL ecotype was recently *** was an adaptive radiation after directional evolution in the Chl bla ratio *** in chlorophyllide a oxygenase(CAO) and positive selection on Clp protease contributed to the directional evolution of *** recombinant fragments of CAO were correlated with a large group of shared coevolving *** of positive selection was found in both subunits of *** bla ratio evolution,as annotated by molecular evidence,appears to be among the crucial reasons that explain how prochlorococcus has become the dominant photosynthetic organism in the ocean.

关键词： prochlorococcus Ch1 b/a ratio Adaptive evolution Trait evolution Ecotype differentiation

Construction of habitat suitability models(HSMs) for benthic macroinvertebrate and their applications to instream environmental flows:A case study in Xiangxi river of Three Gorges reservior region,china

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progress in Natural Science:Materials International 2009年第3期19卷 359-367页

作者： Fengqing Li a,b, Qinghua Caia,*, Xiaocheng Fu a,b, Jiankang Liu a a State Key Laboratory of Freshwater Ecology and biotechnology, Institute of Hydrobiology, chinese academy of sciences, Wuhan 430072, china b graduate university of chinese academy of sciences, beijing 100039, china State Key Laboratory of Freshwater Ecology and biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China graduate university of chinese academy of sciences Beijing 100039 China

based on a long-term ecological monitoring, the present study chose the most dominant benthic macroinvertebrate (baetis spp.) as tar- get organisms in Xiangxi river, built the habitat suitability models (HSMs) for water depth, current velocity and substrate, respectively, which is the first aquatic organisms model for habitat suitability in the chinese Mainland with a long-term consecutive in situ measurement. In order to protect the biointegrity and function of the river ecosystem, the theory system of instream environmental flow should be cat- egorized into three hierarchies, namely minimum required instream flow (hydrological level), minimum instream environmental flow (bio- species level), and optimum instream environmental flow (ecosystem level). These three hierarchies of instream environmental flow models were then constructed with the hydrological and weighted usable area (WUA) method. The results show that the minimum required instream flow of Xiangxi river calculated by the Tennant method (10% of the mean annual flow) was 0.615 m3 s 1; the minimum instream environmental flow accounted for 19.22% of the mean annual flow (namely 1.182 m3 s 1), which was the damaged river channel flow in the dry season; and 42.91% of the mean annual flow (namely 2.639 m3 s 1) should be viewed as the optimum instream environmental flow in order to protect the health of the river ecosystem, maintain the instream biodiversity, and reduce the impact of small hydropower stations nearby the Xiangxi river. We recommend that the hydrological and biological methods can help establish better instream environmental flow models and design best management practices for use in the small hydropower station project.

关键词： Habitat suitability model Weighted usable area Instream environmental flow benthic macroinvertebrate Xiangxi river Three Gorges reservoir

The boundary of palaearctic and oriental realms in western china

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progress in Natural Science:Materials International 2008年第7期18卷 833-841页

作者： Ling Chen a,b,c, Yanling Songd,*, Shufang Xu e a Northwest Institute of plateau biology, chinese academy of sciences, Xining 810001, china b graduate university of the chinese academy of sciences, beijing 100039, china c National Science Foundation of china, beijing 100085, china d Institute of Zoology, chinese academy of sciences, beijing 100101, china e beijing academy of Agriculture and Forestry sciences, beijing 100097, china Northwest Institute of plateau biology Chinese Academy of Sciences Xining 810001 China graduate university of the chinese academy of sciences Beijing 100039 China National Science Foundation of china Beijing 100085 China Institute of Zoology Chinese Academy of Sciences Beijing 100101 China beijing academy of Agriculture and Forestry sciences Beijing 100097 China

In the world-wide zoogeographic division, there has been no consentaneous understanding about the delimitation between palaearctic and oriental realms in western china. In this study, we will discuss the division based on amphibian distribution in Shaanxi, Gansu, Sichuan, Yunnan, and Tibet according to species coefficient similarity between each zoogeographic province. The results show that the northern border lies from Qinling Mountains–Feng Xian (Shaanxi)–Debu (Gansu)–Aba (Sichuan)–batang–bomi (Tibet), to Linzhi districts, and the southern border is from Taibai–Feng Xian in Shaanxi–Wen Xian (Gansu)–Songpan–Kangding–Daocheng (Sichuan), to Zhongdian–Gongshan in Yunnan, and westward to Motuo and bomi district in Tibet.

关键词： Amphibian Zoogeography palaearctic Oriental Hengduan Mt.

Comparison of dynamic changes in endogenous hormones and sugars between abnormal and normal Castanea mollissima

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progress in Natural Science:Materials International 2008年第6期18卷 685-690页

作者： Tao Liua,b,Yunqian Hua,*,Xiaoxian Li a aKunming Institute of botany,chinese academy of sciences,Kunming 650204,china bgraduate university of the chinese academy of sciences,beijing 100049,china Kunming Institute of botany Chinese Academy of Sciences Kunming 650204 China graduate university of the chinese academy of sciences Beijing 100049 China

To elucidate the possible functions of endogenous hormones in the flowering of chestnut,concentrations of four endogenous hor-mones[indole-3-acetic acid(IAA),gibberellic acid(GA),abscisic acid(AbA),zeatin riboside(Zr))and the soluble sugars content were measured in both normal and developmentally abnormal chinese chestnut(Castanea mollissima)during flowering and fruiting *** results showed that the contents of Zr,AbA,and GA exhibited a significant dierent pattern in normal trees from that in abnormal trees,while the contents of IAA and soluble sugars showed a similar change pattern between *** results suggest that quantitative changes in endogenous hormones may correspond to dierent flowering and fruiting mechanisms.

关键词： Castanea mollissima Endogenous hormones Soluble sugars

Overview of HbV whole genome data in public repositories and the chinese HbV reference sequences

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progress in Natural Science:Materials International 2008年第1期18卷 13-20页

作者： Guanghua Wu a,b, Huiguo Ding c, Changqing Zeng b,* a graduate School of chinese academy of sciences, beijing 100049, china b beijing Institute of Genomics, chinese academy of sciences, beijing 101300, china c beijing Youan Hospital, Capital Medical university, beijing 100069, china graduate School of chinese academy of sciences Beijing 100049 China beijing Institute of Genomics Chinese Academy of Sciences Beijing 101300 China beijing Youan Hospital Capital Medical University Beijing 100069 China

The number of Hepatitis b virus (HbV) whole genomic sequences in public nucleotide databases (Genbank, EMbL, and DDbJ) had reached 866 by January 1, 2007. Coming from 46 countries and regions, these sequences were categorized as eight genotypes (A–H). With the statistical and phylogenetic analysis on all available complete genomic data of HbV, we here present an overview of HbV sequences in public databases. From all registered 229 HbV genomes in chinese regions as well as 59 sequencing data from our research group, we report the establishment of reference sequences of HbV strains prevailing in china. These analyses provide clues for the effects of HbV genotypes in host clinical progressions, geographic distribution of the infection, and the viral evolutionary history. Moreover, the viral sequence reference would be helpful in the identiffcation of various HbV mutations. based on the analysis of various public databases, we suggest that the chinese HbV database with the clinical information should be constructed.

关键词： public databases HbV genomic sequences Genotype Subtype chinese reference sequences