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ON BOUNDARY TREATMENT FOR THE NUMERICAL SOLUTION OF THE INCOMPRESSIBLE NAVIER-STOKES EQUATIONS WITH FINITE DIFFERENCE METHODS

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Journal of Computational Mathematics 1996年第2期14卷 135-142页

作者： Huang, lc CHINESE ACAD SCI LSECINST COMPUTAT MATH & SCI ENGN COMPBEIJINGPEOPLES R CHINA

Immunohistochemical study on gastroenteric nervous system in trisomy 16 mice:an animal model of Down syndrome

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World Journal of Gastroenterology 2000年第6期6卷 793-799页

作者： lc Busch W Kuhnel Institute of Anatomy Medical University of LubeckGermany

AIM To study the development of gastroentericnervous system in trisomy 16 mouse *** gastroenteric nervous system in trisomy 16mice and their normal littermates,serving ascontrols from embryonic days 13 to 18(ED13-18)was identified by using primary antibody againstprotein gene product(PGP)*** Trisomy 16 mouse breeding andtrisomy 16 mouse embryos were identified fromtheir normal littermates by chromosomeexamination;PGP 9.5 *** Trisomy 16 mice, as an animal model for Down syndrome, has abnormality not only in several systems and organs but also in gastroenteric innervation. This report describes for the first time that the development of the gastroenteric nervous system was not only delayed but also pathological.

关键词： gastrointestinal system down syndrome immunohistochemistry trisomy 16 mouse nervous system protein gene product 9.5

Electrolytic Domain Boundary between Ionic and Electronic Conduction of Doped Ceria

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Journal of Materials Science & Technology 1998年第5期14卷 451-456页

作者： Li, lc Lu, LZ Xie, HQ Chinese Acad Sci Inst Chem Met Beijing 100080 Peoples R China

The electrolytic domain boundary (EDB) of doped ceria between ionic and electronic conduction is theoretically investigated with the consideration of defect association. Data from the early reports on EDB of singly, double and triply doped ceria are summarized and interpreted based on the theoretical investigation. It is proposed that samarium and gadolinium among the rare earth elements are mostly suitable for the main dopants of ceria, while further minor additions of other elements can benefit the improvement of the EDB.

关键词： Cerium compounds

Binderless Carbon/Graphite Materials

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Journal of Materials Science & Technology 1997年第3期13卷 184-188页

作者： Zhou, SM Xia, JT Yan, lc Dept. of Chemistry and Chemical Engineering Hunan University Changsha 410082 China

High performance binderless carbon bodies can be manufactured from the mesophase raw material derived from petroleum pitch, which is ground into fine powders less than 10 mu m, and directly moulded, then sintered at 1000 degrees C without any kind of binder. The sintered bodies have a bulk density of 1.69 g/cm(3), bending strength of 91.2 MPa. Shore hardness of 100, porosity of only 7.2%, and electrical resistivity of 60x10(-6) Omega m. The bodies graphitized at 2800 degrees C have a bulk density of 1.88 g/cm(3), bending strength of 82 MPa. Shore hardness of 85, porosity of 5.4%, and electrical resistivity of 12x10(-6) Omega m. The scanning electron micrographs of the section show that the bodies possess an extremely dense and homogeneous structure. Infra-red spectrum analysis shows that carbonyls introduced when ground or activated are one of the key factors determining the selfbinding and selfsintering properties of the mesophase fine powders, and the structure and strength of the sintered bodies.

关键词： Carbon

Free C *- algebras and the problem of uniqueness of extension in non-commutative Hahn-Banach Theorem

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Chinese Science Bulletin 1997年第13期42卷 1076-1079页

作者： Zhang, lc Ma, JP Department of Mathematics Nanjing University Nanjing 210093 China

1 Introduction and main resultsaRVESON in ref. [1] generalized the classical Hahn-Banach Extension Theorem for linear func-tionals to the self-adjoint linear closed subspace of C~* -algebras. From then on numerous au-thors have given various generalizations of the non-commutative Hahn-Banach-Arveson Theo-rem of ref. [1]. The following extension theorem is due to G. Wittstock.

关键词： Free C* -algebras complete contraction hereditary C* -subalgebras operator spaces.

Effects of human disturbance on nest placement of the woodpigeon (Columba palumbus): a case study from the Middle Atlas, Morocco

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Integrative Zoology 2014年第3期9卷 349-359页

作者： saâd HANANE Forest Research Center High Commissariat for WaterForests and Desertification ControlRabat-AgdalMorocco

The woodpigeon(Columba palumbus)is a common and widespread bird in Morocco(North Africa).I examined,over 2 years(2010 and 2011),the breeding density and nest placement of this game species in relation to nest site habitat and degree of human *** study area was in the Middle Atlas Tighboula mountain forest,Morocco,in a disturbed and an undisturbed *** data collected in the 2 study sites,I aimed to identify the factors influencing the placement of nests within holm oak trees(Quercus rotundifolia)and their densities.I found that habitat structures,influenced by grazing disturbance,have affected nesting density and the location of nests of this *** place their nests in a higher position(3.42±0.19 m)when disturbance intensity is high and lower(1.68±0.1 m)when disturbance intensity is low,and show higher nesting density in less disturbed zone(3.1±0.4 nests/ha)than in highly disturbed zones(1.4±0.2 nests/ha).Grazing disturbance could pose a threat to population persistence at a broader scale and could potentially reduce the abundance of this species by altering the composition and the structure of the forest nesting *** multi-scale studies are needed to assess the effects of different levels of grazing disturbance on woodpigeon nest density and placement,and to enhance our knowledge of the breeding behavior of this game species under variable environments.

关键词： breeding density Columba palumbus holm oak Middle Atlas Morocco nest location woodpigeon

PYRIDINATION OF POLY(VINYL CHLORIDE) via A HOMOLYTIC PATHWAY

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Chinese Journal of Polymer Science 2007年第3期25卷 297-302页

作者： sad Moulay Zakia Zeffouni Laboratoire de Chimie-Physique Moléculaire et Macromoléculaire Faculté des Sciences de l'Ingénieur Département de Chimie IndustrielleUniversité Sad Dahlab de BlidaRoute de SoumaB. P. 270Blida 09000Algeria

PVC was subjected to a chemical modification aiming at replacing the chlorine atoms by pyridine groups via a homolytic route. Pyridine groups were peculiarly affixed to the PVC matrix via a carbon-carbon bond rather than a carbonnitrogen one. PVC was first iodinated using the Conant-Finkelstein reaction, followed by the application of the homolytic conditions of Minisci to generate pyridinated PVC with a varying degree of substitution. The extent of substitution was not high; the reaction on 30% iodinated PVC afforded a degree of modification no greater than 3%.

关键词： Conditions of Minisci Iodinated PVC Pyridinated PVC

Changes in plant community diversity and aboveground biomass along with altitude within an alpine meadow on the Three-River source region

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Chinese Science Bulletin 2012年第27期57卷 3573-3577页

作者： sa WenJun AN LiZhe sa Wei Institute of Botany Science School of Life SciencesLanzhou UniversityLanzhou 730000China School of Life Science Qinghai UniversityXining 810008China

The grassland is an important component of terrestrial ecosystems and plays a significant role in biodiversity and ecosystem *** the present study,the changes of plant species diversity and aboveground biomass productivity were examined along with the altitude in natural alpine grassland in the source region of three rivers on the Qinghai-Tibetan *** experimental locations were selected with altitudes ranging from 3862 to 4450 m above sea level(a.s.l.).The results indicated that Kobresia pygmaea meadow,Kobresia humilis meadow and salix cupularis shrub meadow had higher indices of diversity and aboveground *** distribution of species diversity,richness and aboveground biomass showed similarly unimodal patterns across the altitude gradient with the highest indices appeared at mid-altitudes *** changing trend of species diversity,richness and evenness also showed significant unimodal patterns with total aboveground biomass,and the highest species diversity occurred at intermediate level of *** research would provide a valuable reference for the protection of grassland biodiversity and maintaining of the grazing ecosystem function in the source region of the Three Rivers.

关键词：植物群落多样性地上生物量海拔高度高寒草甸三江源地区植物物种多样性生态系统功能生物多样性

A GEOMETRIC THEORY IN INVESTIGATION ON MODE LOCALIZATION AND FREQUENCY LOCI VEERING PHENOMENA

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Acta Mechanica Solida Sinica 1995年第4期8卷 349-355页

作者： Liu, JK Zhao, lc Fang, T NORTHWESTERN POLYTECH UNIV XIAN 710072PEOPLES R CHINA

According to the mapping theory in complex plane, the geometric features of eigen frequency loci of systems undergoing free vibrations are investigated. It is concluded that the phenomena of curve coalescence and veering can be described in a unified manner from the singularities of mapping from the complex parameter plane onto the complex frequency plane. The formation of a branch point in the parameter Space is the foundation of explaining localization and veering phenomena. By the use of condensation to reduce the dimension of a system, the scope of application of the geometric theory is widely expanded. The theory is applied to examples to verify the validity of the proposed approach. The present work is an improvement and extension of recent work by M. S. Traintafyllou et al..

关键词： complex plane mapping mode localization frequency loci veering condensation