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Chinese Science Bulletin 1990年第8期35卷 655-658页

作者：濮祖荫霍澎涛严明刘振兴 Department of Geophysics Peking University Beijing 100871 PRC Center for Space Research and Applications Academia Sinica Beifing 100080 PRC

A number of investigations have provided convincing evidence showing that the flux transfer events (FTEs) result from pachy reconnection at the magnetopause and play an important role in the solar wind-magnetosphere c... 详细信息

关键词： coalescence magnetic island vortex.

Reconstructing the phytogeny of new world monkeys(platyrrhini):evidence from multiple non-coding loci

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Current Zoology 2019年第5期65卷 579-588页

作者： Xiaoping WANG Burton K.LIM Nelson TING Jingyang HU Yunpeng LIANG Christian ROOS Li YU State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan Yunnan UniversityKunmingChina School of Life Sciences Yunnan UniversityKunmingChina epartm ent of Natural History Royal Ontario MuseumTorontoONCanada Department of Anthropology and Institute of Ecology and Evolution University of OregonEugeneOregonUSA State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunmingChina Kunming College of Life Science University of Chinese Academy of SciencesKunmingChina Gene Bank of Primates and Primate Genetics Laboratory German Primate CenterLeibniz Institute for Primate ResearchKellnerwegGottingenGermany

Among mammalian phylogenies,those characterized by rapid radiations are particularly problematic.The New World monkeys(NWMs,Platyrrhini)comprise 3 families and 7 subfamilies,which radiated within a relatively short time period.Accordingly,their phylogenetic relationships are still largely disputed.In the present study,56 nuclear non-coding loci,including 33 introns(INs)and 23 intergenic regions(IGs),from 20 NWM individuals representing 18 species were used to investigate phylogenetic relationships among families and subfamilies.Of the 56 loci,43 have not been used in previous NWM phylogenetics.We applied concatenation and coalescence tree-inference methods,and a recently proposed question-specific approach to address NWM phylogeny.Our results indicate incongruence between concatenation and coalescence methods for the IN and IG datasets.However,a consensus was reached with a single tree topology from all analyses of combined INs and IGs as well as all analyses of question-specific loci using both concatenation and coalescence methods,albeit with varying degrees of statistical support.In detail,our results indicated the sister-group relationships between the families Atelidae and Pitheciidae,and between the subfamilies Aotinae and Callithrichinae among Cebidae.Our study provides insights into the disputed phylogenetic relationships among NWM families and subfamilies from the perspective of multiple non-coding loci and various tree-inference approaches.However,the present phylogenetic framework needs further evaluation by adding more independent sequence data and a deeper taxonomic sampling.Overall,our work has important implications for phylogenetic studies dealing with rapid radiations.

关键词： coalescence concatenation non-coding nuclear genes primates phylogenetics

EFFECTS OF MASS TRANSFER ON THE THINNING AND RUPTURE OF A PLANE PARALLEL LIQUID FILM

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Chinese Journal of Chemical Engineering 1994年第3期2卷 33-49页

作者：李佟茗

The effects of mass transfer and physical properties upon the thinning and rupture of adraining plane parallel film are investigated.An equation is derived in which the thinning rate is afunction of bulk properties.surface properties(surface tension,surface viscosities,and the variationof surface tension with surface concentration),intermolecular forces(London-van der Waals forcesand electrostatic double layer forces),adsorption and surface diffusion coefficients,bubble size andfilm thickness.An estimation for the critical thickness at which a film rupture is carried out and thecoalescence time is obtained by integration to the critical thickness,The coalescence time is predictedas a function of bulk and surface properties,London-van der forces,adsorption and surfacediffusion coefficients,and bubble size.

关键词： bubble coalescence thin film drainage mass transfer effect on coalescence

MACROPROCESS OF PARTICLE FORMATION IN SUSPENSION POLYMERIZATION OF STYRENE WITH INORGANIC STABILIZER SYSTEM

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Chinese Journal of Chemical Engineering 1993年第1期1卷 40-48页

作者：方仕江潘仁云周其云唐舜英袁惠根

The macroprocess of particle formation from suspension droplets of styrene in a pdymerizationsystem was investigated.Inorganic hydroxyapatite or its mixture with polyvinyl alcohol as thepolymerization system was used.Those items such as the effects of the Weight fraction of dispersed-phase,the amount of the inorganic stabilizer and the agitation speed on the breakup and coalescence of thetransient dispersed drops etc.Were examined.Results showd that the dynamic behavior of the transi-ent polymer droplets changed in the presence of the suspension stabilizer during the reaction.

关键词： styrene suspension polymerization inorganic stabilizer drop size and drop size distribution breakup and coalescence

ON THE LEAST EIGENVALUE OF A GRAPH

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Systems Science and Mathematical Sciences 1993年第3期6卷 269-272页

作者： HONG Yuan Department of Mathematics, East China Normal University, Shanghai 200062, China 华东师范大学上海

Let G be a simple graph with n vertices and λn（G） be the least eigenvalue of G.In this paper, we show that, if G is connected but not complete, then λn（G）≤λn(Kn-11)and the equality holds if and only if G Kn-11, where Kn-11, is the graph obtained by thecoalescence of a complete graph Kn-1 of n-1 vertices with a path P2 of length one of itsvertices.

关键词： Adjacency matrix eigenvalue coalescence

Multi-bubble motion behavior of uniform magnetic field based on phase field model

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Chinese Physics B 2020年第3期29卷 303-311页

作者：朱昶胜胡震王凯明 School of Computer and Communication Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Gansu Advanced Processing and Recycling of Non-Ferrous Metal Lanzhou University of TechnologyLanzhou 730050China

Aiming at the interaction and coalescence of bubbles in gas–liquid two-phase flow, a multi-field coupling model was established to simulate deformation and dynamics of multi-bubble in gas–liquid two-phase flow by coupling magnetic field, phase field, continuity equation, and momentum equation. Using the phase field method to capture the interface of two phases, the geometric deformation and dynamics of a pair of coaxial vertical rising bubbles under the applied uniform magnetic field in the vertical direction were investigated. The correctness of results is verified by mass conservation method and the comparison of the existing results. The results show that the applied uniform magnetic field can effectively shorten the distance between the leading bubble and the trailing bubble, the time of bubbles coalescence, and increase the velocity of bubbles coalescence. Within a certain range, as the intensity of the applied uniform magnetic field increases, the velocity of bubbles coalescence is proportional to the intensity of the magnetic field, and the time of bubbles coalescence is inversely proportional to the intensity of the magnetic field.

关键词： bubbles coalescence uniform magnetic field numerical simulation phase field method

Study on Architecture-Oriented Information Security Management Model for Using Mobile Devices Control

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Chinese Business Review 2018年第9期17卷 442-464页

作者： Wei-ming Ma Cheng Shiu University Taiwan

The popularization of mobile devices has caused considerable impact on the security of the military of the Republic of China.The military barrack-areas have long been faced the control of mobile devices four issues:the lack of accurate use of resources,the lack of protection of the mobile device from the overall point of view,the unclear division of responsibility among specialized agencies,and unclear members’responsibilities for their own duties.This study applies the structure behavior coalescence(SBC)methodology to integrate the organizational structure of the participating management and control units with effective management behaviors in a visualized and useful manner.The units can effectively communicate with each other and solve the four issues faced by the military barrack-areas for the control of mobile devices.This research fulfills improving the lack of control of the military mobile devices by using of management resources effectively and the establishment of mobile devices management with the overall concept,and strengthening the rights and responsibilities and information security awareness,through the logical verification and enterprise interview results.

关键词： information security management structure behavior coalescence mobile devices Military Army

Synthesis and Conformational Studies on [3.3.3]Metacyclophane Oligoketone Derivatives, and Their Metal Ion Recognition

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International Journal of Organic Chemistry 2015年第2期5卷 126-135页

作者： Louis Korbla Doamekpor Raphael Kwaku Klake Vincent Kodzo Nartey Takehiko Yamato Oti Gyamfi Dennis Adotey Department of Chemistry University of Ghana Accra Ghana Department of Chemistry Saga University Saga Japan Ghana Atomic Energy Commission Accra Ghana

Chemical reactions were used to synthesize 2,11,20-tris(ethanedithia)-9,18,27-trimethoxy-6,15, 24-tri-tert-butyl[3.3.3]metacyclophane 2 and 2,11-bis(ethanedithia)-9,18,27-trimethoxy-6,15,24-tri-tert-butyl[3.3.3]metacyclophane 4 from 6,15,24-tri-tert-butyl-9,18,27-trimethoxy[3.3.3]meta-cyclophane-2,11,20-trione 1 and -2,11-dione 3. The yields of 2 and 4 were 70% and 81% respectively. The conformations of the synthesized compounds 2 and 4 were studied using mainly solution Proton Nuclear Magnetic Resonance (1H NMR) spectroscopic methods. Compounds 2 and 4 were found to have a partial-cone conformation. Detailed variable temperature Proton Nuclear Magnetic Resonance studies further confirmed the partial-cone conformation for the two products, 2, 4. During the variable temperature nuclear magnetic resonance spectroscopic studies, compound 2 was found to have a coalescence temperature of about 0?C. Extraction of silver ions with compound 2 gave an extractability of 82% while the parent compound 1 showed zero (0) silver affinity. A 1:1 mol/mol mixture of compound 2 and silver ions studied by solution 1H NMR revealed a novel “Molecular Roulette” type of motion.

关键词： Metacyclophanes Macrocyclic Compounds Cone Partial-Cone Conformation Variable Temperature Proton Nuclear Magnetic Resonance Spectroscopy coalescence Temperature

Demographic Expansion and Contraction in a Neotropical Fish during the Late Pleistocene-Holocene

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Open Journal of Statistics 2019年第4期9卷 470-483页

作者： Carolina L. N. Costa S. Ivan Perez José Louvise Carlos H. Tonhatti Rute B. G. Clemente-Carvalho Ana C. Petry S. F. dos Reis Programa de Pós-Graduacao em Ecologia Universidade Estadual de Campinas Sao Paulo Brazil División Antropología Facultad de Ciencias Naturales y Museo Universidad Nacional de La Plata CONICET La Plata Argentina Faculdade do Vale do Jaguaribe Ceará Brazil Programa de Pós-Graduacao em Genética Universidade Estadual de Campinas Sao Paulo Brazil Deparment of Biology Queen’s University Ontario Canada Núcleo em Ecologia e Desenvolvimento Sócio-Ambiental de Macaé Universidade Federal do Rio de Janeiro Rio de Janeiro Brazil Departamento de Biologia Animal Universidade Estadual de Campinas Sao Paulo Brazil

Demographic changes during the late Pleistocene-Holocene left signatures in the DNA of contemporary populations. These signatures reveal demographic phenomena like the increase or decrease in effective population size. In this paper we searched for signatures of demographic change in the DNA of the Neotropical freshwater fish Poecilia vivipara. Also, we investigated whether demographic changes are correlated with palaeoclimatic events of the late Pleistocene-Holocene, in particular, if changes in effective population size are correlated with expansion and contraction of available habitats, induced by global ice-volume changes and sea-level fluctuations. We used Bayesian Skyline Plot (BSP) analysis with sequences from the mitochondrial gene cytochrome b to estimate the ancestral demography of the Neotropical freshwater fish P. vivipara. To test the assumptions of neutrality and absence of population structure we used Tajima’s D and Spatial Analysis of Molecular Variance (SAMOVA), respectively. Effective population size of P. vivipara remained stable until 75,000 years ago, increased by 10-fold reaching a maximum at approximately 25,000 years ago, then suddenly declined at the Pleistocene-Holocene boundary. Variation in effective population size in P. vivipara correlates with expansion and contraction of habitats induced by sea-level fluctuations, caused by the advance and retreat of ice sheets during the Last Glacial Maximum (LGM).

关键词： Ancestral Population Dynamics coalescence Bayesian Skyline Plot Mitochondrial DNA Last Glacial Maximum

Synthesis and Conformational Studies of Some Metacyclophane Compounds

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International Journal of Organic Chemistry 2012年第2期2卷 152-158页

作者： Louis Korbla Doamekpor Vincent Kodzo Nartey Raphael Kwaku Klake Takehiko Yamato Department of Chemistry University of Ghana Accra Ghana epartment of Chemistry Saga University Saga Japan

Various [3.3.3]metacyclophane derivatives were synthesized from 6,15,24-tri-tert-butyl-9,18,27-trimethoxy [3.3.3] metacyclophane-2,11,20-trione 1 using simple chemical reactions. The conformations of the synthesized compounds were studied using mainly solution Proton Nuclear Magnetic Resonance (1H NMR) spectroscopic methods. Two of the synthesized compounds 5, 6, were found to have a partial cone conformation with the third, 4, having the cone conformation. Detailed variable temperature Proton Nuclear Magnetic Resonance studies further confirmed the partialcone conformation for the two products, 5, 6. During the variable temperature nuclear magnetic resonance spectroscopic studies, 6,15,24-tri-tert-butyl-9,18,27-trimethoxy[3.3.3]metacyclophane-2,11,20-triol was found to have a coalescence temperature of about 0?C.

关键词： Metacyclophanes Calixarenes Cone Partial-Cone Conformers Variable Temperature Proton Nuclear Magnetic Resonance Spectroscopy coalescence Temperature