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Mineralogy and crystal structure determination of Mg-fillowite

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Science china Earth sciences 2005年第5期48卷 635-646页

作者： MA Zhesheng 1 , SHI Nicheng 1 & YE Danian 2.1. china University of Geosciences, {2. 100083, china 2. Institute of Geology, chinese academy of sciences, {2. 10002., china china University of Geosciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China

Accurate crystal structure determination of complex phosphate Mg-fillowite ? Na2.a(Mn4Mg2.e)7[PO4]6 has been finished. Mg-fillowite occurs in muscovite-pegmatite in the Altay area, Xinjiang, china. It is of the trigonal lattice, with space group R-3, unit cell a=1.5143(3) nm, c=4.3191(2. nm, V=8.5736 nm3, Z = 18. The R-factor of the determination accuracy is R (I > 2. ( I )) = 0.0776. The cationic polyhedra consist of two kinds of structural units: compound col- umn and screw column. In three-dimensional space, they are linked with each other through corner sharing or edge sharing to build the entire structure. There are 45 atoms in an asymmetric unit and 72. atoms in a unit cell. In terms of types and connection manners of the coordination polyhedra, the degree of complicity is rarely seen in all mineral crystal structures. Study of such a structure is significant for the classification of phosphate and the building rule of coordination polyhedra in a complex crystal structure.

关键词： Mg-fillowite, complex phosphate, crystal structure, coordination polyhedron.

Experimental investigation and numerical simulation on the effect of fissure water pressure in vertical sliding surface

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Science china(Technological sciences) 2005年第Z1期48卷 53-64页

作者： ZHANG Lei1,2. LI Shihai1, LIAN Zhenzhong1,2.& WANG Yuannian1 1. Institute of Mechanics, chinese academy of sciences, beijing 100080, {2. 2. Graduate School, chinese academy of sciences, beijing 100060, {2. Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China Graduate School Chinese Academy of Sciences Beijing 100060 China

This paper studies the effect of fissure water pressure in different fractures on the critical angle of landslide by laboratory investigation and numerical simulation in order to understand the mechanisms of fissure water pressure on landslide stability. Laboratory observations show that the effect of fissure water pressure on the critical angle of landslide is little when the distance between water-holding fracture and slope toe is three times greater than the depth of fissure water. These experimental results are also simulated by a three-dimensional face-to-face contact discrete element method. This method has included the fissure water pressure and can accurately calculate the critical angle of jointed slope when fissure water pressure in vertical sliding surface exists. Numerical results are in good agreement with experimental observations. It is revealed that the location of water-holding structural surface is important to landslide stability. The ratio of the distance between water-holding fissure and slope toe to the depth of fissure water is a key parameter to justify the effect of fissure water pressure on the critical angle of landslide.

关键词： jointed rock slope, discrete element method, fracture in vertical sliding surface, model experiment,fissure water pressure.

Transient species and its properties of melatonin

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Science china Chemistry 2006年第4期49卷 308-314页

作者： ZHU Hongping1,2. ZHANG Zhaoxia1,2. ZHAO Hongwei1, WANG Wenfeng1 & YAO Side1 1. Shanghai Institute of Applied Physics, chinese academy of sciences, Shanghai 2.1800, china 2. Graduate University of the chinese academy of sciences, beijing 100049, china Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai China Graduate University of the chinese academy of sciences Beijing China

The photo-physical and photo-chemical properties of melatonin (ML) werestudied by 2.6 nm laser flash photolysis (LFP). ML undergoes photo-ionization to produce radicalcation of ML (ML^(·+))and hydrated electrons (e_(aq)^-), while excited triplet state ~3ML~* is alsoformed during photolysis. The oxidation via one electron transfer from ML to SO_4^(·+) and thetriplet state of riboflavin (~3RF~*) has been also investigated and the rate constants for theprocess have been determined to be 8.0x10^9 and 1.4x10^9 L·mol^(-1)·s^(-1) respectively. Theradical cation of 2.2.'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS^(·+)) scavengingcapacities of melatonin and other antioxidants are compared in this paper.

关键词： melatonin, laser flash photolysis, photoionization, triplet state.

Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science china Earth sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2.3 & WANG Huijun2.1. Nansen-Zhu International Research Center, Institute of Atmospheric Physics, chinese academy of sciences, {2. 10002., {2. 2. Department of Atmospheric Science, Yunnan University, Kunming 650091, {2. 3. Graduate University of the chinese academy of sciences, beijing 100049, {2. Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of Atmospheric Science Yunnan University Kunming China Graduate University of the chinese academy of sciences Beijing China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

An integrated decision method for prediction of tropical cyclone movement by using genetic algorithm

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Science china Earth sciences 2005年第3期48卷 429-440页

作者： YANG Yuanqin1 & WANG Jizhi2.1. National Meteorological Center, beijing 100081,china 2. {2. academy of Meteorological sciences, beijing 100081, china National Meteorological Center Beijing China chinese academy of Meteorological {2. Beijing China

In this study an integrated decision method for the multi-prediction results of tropical cyclone movements by using genetic algorithm (GA) has been adopted. A genetic learning artifi- cial neural network (GLANN) as a learning mechanism for track prediction was developed through training with the huge samples of typhoon tracks from 1884 to 2.02. The prediction of typhoon motion is to consider how to suit the dynamic change of environment, where typhoon passed through. The neural network structure is described by GA. A fitness function for choice of GA is given to approach the maximum of fitness (the minimum of the errors). Parallel comparing analyses for prediction abilities of unusual typhoon tracks in recent years by GLANN with multi-forecast methods were conducted. More types of cases were employed in the comparing analyses, which consist of the typhoon, Winnie, No.11, in 1997, characterized by a long life over the ocean and in the mainland with severe effect on china, the 10 unusual typhoon tracks in the 1990s, the tracks with landfall and affected action in 1998 and the typhoons born in the Northwestern Pacific and the South china Sea in 2.00, including the 2.—48 h forecast, etc. The results indicated that for prediction ability of typhoon tracks, specially for unusual typhoons, GA decision-making developed in this study is superior to the others.

关键词： genetic algorithm, integrated decision, prediction of tropical cyclone.

Molecular cloning of growth hormone receptor (GHR) from common carp(Cyprinus carpio L.)and identification of its two forms of mRNA transcripts

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Progress in Natural Science:Materials International 2006年第11期16卷 1156-1163页

作者： SUN Xiaofeng~ 1,2., GUO Qionglin~1**, HU Wei~1, WANG Yaping~1 and ZHU Zuoyan~1(1. State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, chinese academy of sciences, Wuhan 430072. china 2. Graduate School 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 School of chinese academy of sciences Beijing 100039 China

The cDNA of growth hormone receptor (GHR) was cloned from the liver of 2.year common carp (Cyprinus carpio L.) by reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end (RACE). Its open reading frame (ORF) of 1806 nucleotides is translated into a putative peptide of 602.amino acids, including an extracellular ligand-binding domain of 2.4 amino acids (aa), a single transmembrane domain of 2. aa and an intracellular signal-transduction domain of 334 aa. Sequence analysis indicated that common carp GHR is highly homologous to goldfish (Carassius auratus) GHR at both gene and protein levels. Using a pair of gene-specific primers, a GHR fragment was amplified from the cDNA of 2.year common carp, a 2.4 bp product was identified in liver and a 32. bp product in other tissues. The sequencing of the products and the partial genomic DNA indicated that the difference in product size was the result of a 97 bp intron that alternatively spliced. In addition, the 32. bp fragment could be amplified from all the tissues of 4-month common carp including liver, demonstrating the occurrence of the alternative splicing of this intron during the development of common carp. Moreover, a semi-quantitative RT-PCR was performed to analyze the expression level of GHR in tissues of 2.year common carp and 4-month common carp. The result revealed that in the tissues of gill, thymus and brain, the expression level of GHR in 2.year common carp was significantly lower than that of 4-month common carp.

关键词： growth hormone receptor (GHR) molecular cloning transcript expression analysis common carp.

Anatomy and ontogeny of unisexual flowers in dioecious Woonyoungia septentrionalis (Dandy) Law (Magnoliaceae)

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Journal of Systematics and Evolution 2009年第4期47卷 263-272页

作者： ~(1,2.Lin FU ~1Qing-Wen ZENG ~1Jing-Ping LIAO ~1Feng-Xia XU~* 1(South china Botanical Garden,chinese academy of sciences,Guangzhou 510650,china) 2.Graduate University of chinese academy of sciences,beijing 100049,china) (South china Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China) (Graduate University of chinese academy of sciences Beijing 100049 China)

Woonyoungia septentrionalis(Dandy)Law is a dioecious species with unisexual flowers in Magnoliaceae. The floral morphology and structure of the species are conspicuously different from other species and are important to the study of floral phylogeny in this *** floral anatomy and ontogeny were investigated to evaluate the systematic position of ***,using scanning electron microscopy and light microscopy. All of the floral organs are initiated acropetally and *** carpels are of conduplicated type without the differentiation of stigma and *** degenerated stamens in the female flowers have the same structures as the normal stamens at the earlier developmental stages,but they do not undergo successive development and eventually *** male floral apex was observed to have the remnants of carpels in a few investigated *** the bisexual flower features could be traced both in the male and female flowers in ***,it suggests that the flower sex in Magnoliaceae tends toward *** well as the unisexual flowers,the reduced tepals and carpels and concrescence of carpels conform to the specialized tendency in Magnoliaceae,which confirms the derived position of *** in this *** the initiation pattern of floral parts of *** is very similar to other species in this family,it needs further investigation and especially comparison with species in Kmeria to evaluate the separation of Woonyoungia.

关键词： floral anatomy Magnoliaceae ontogeny Woonyoungia septentrionalis(Dandy)Law.

Durinskia baltica(Dinophyceae),a newly recorded species and genus from china, and its systematics

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Journal of Systematics and Evolution 2011年第5期49卷 476-485页

作者： 1,2.Qi ZHANG 1~Guo-Xiang LIU 1~Zheng-Yu HU 1(State Key Laboratory of Freshwater Ecology and Biotechnology,Institute of Hydrobiology,chinese academy of sciences,Wuhan 430072.china) 2.Graduate University,chinese academy of sciences,beijing 100049,china) (State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China) (Graduate University Chinese Academy of Sciences Beijing 100049 China)

A freshwater dinoflagellate was identified as Durinskia baltica(Levander) Carty & Cox by morphological characteristics,with the plate formula:Po,x,4,2.,6,5c,4s,5,*** was a newly recorded dinoflagellate genus for china with two anterior intercalary plates and six characteristic precingular *** sequences of the small and large subunit ribosomal DNA and internal transcribed spacer sequences for the dinoflagellate cells were obtained from field *** phylogenetic results indicated Durinskia species could cluster into a monophyletic group,which were distinct from Peridinium *** to morphological and molecular evidence,it was agreed that the genus Durinskia was separated from the genus Peridinium,which could be a polyphyletic *** addition,*** was an infrequent diatom-harboring dinoflagellate which was known to possess an endosymbiotic diatom or diatom-like *** phylogenetic analyses indicated that *** had a close affinity with Peridiniopsis penardii and ***,common freshwater bloom-forming species in china.

关键词： china Durinskia Durinskia baltica new record phylogeny.

Strict constraints on 2. primitive pairs for engineering symbol recognition:Theory and application

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Science china(Information sciences) 2012年第5期55卷 1032-1041页

作者： LI Ting 1,2.QIU XianJie 1,HUANG He 1 & WANG ZhaoQi 1 1 Virtual Reality Laboratory,Institute of Computing Technology chinese academy of sciences,beijing 100190,{2. 2.Graduate University of chinese academy of sciences,beijing 100049,{2. Virtual Reality Laboratory Institute of Computing Technology Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

Geometric constraints on the line-line pair,line-arc pair and arcarc pair are *** con-straints are able to encode the geometric relations between lines,arcs and circles.A geometric proof is presented to demonstrate that the constraints are stable under translation,rotation,uniform scaling or reflection of the primitive *** on the constraints,an algorithm for recognizing symbols in drawings is ***-perimental results show that,compared with three other methods,our method can distinguish more primitive pairs and has higher accuracy in engineering symbol recognition.

关键词： coordinated multi-point transmission multicell cooperation capacity analysis MIMO-OFDM power allocation frequency selective MIMO channel