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Acta Geologica Sinica(English Edition) 2007年第6期81卷 925-930页

作者： LI Gang WAN Xiaoqiao Helmut WILLEMS David j. BATTEN State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China China University ofGeosciences Beijing 100083 China Department of Geosciences University of Bremen Klagenfurter Strαβe 2 28359 Bremen Germany School of Earth Atmospheric and Environmental Sciences University of Manchester Oxford Road Manchester M13 9PL and Institute of Geography and Earth Sciences University of Wales Aberystwyth SY23 3DB UK

The diagnosis of the conchostracan genus Tenuestheria from the Lanxi Formation in jinhua, Zhejiang Province in Southeast China is revised following an examination of the type species under a scanning electron microscope, which revealed some morphological features on the carapace that had not been recognized previously. The importance of the Tenuestheria Fauna is considered in the context of correlation of six Turonian-Santonian formations in this region of China. The value of the Cenomanian Nemestheria and Turonian Linhaiella faunas in correlating the underlying early Late Cretaceous formations is also noted.

关键词： conchostraca Tenuestheria Upper Cretaceous Southeast China

Effect of viscous dissipation and heat source on flow and heat transfer of dusty fluid over unsteady stretching sheet

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Applied Mathematics and Mechanics(English Edition) 2012年第8期33卷 1001-1014页

作者： B.j.GIREESHA G.S.ROOPA C.S.BAGEWADI Department of Studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451KarnatakaIndia

This paper investigates the problem of hydrodynamic boundary layer flow and heat transfer of a dusty fluid over an unsteady stretching surface. The study considers the effects of frictional heating （viscous dissipation） and internal heat generation or ab- sorption. The basic equations governing the flow and heat transfer are reduced to a set of non-linear ordinary differential equations by applying suitable similarity transformations. The transformed equations are numerically solved by the Runge-Kutta-Fehlberg-45 order method. An analysis is carried out for two different cases of heating processes, namely, variable wall temperature （VWT） and variable heat flux （VHF）. The effects of various physical parameters such as the magnetic parameter, the fluid-particle interaction pa- rameter, the unsteady parameter, the Prandtl number, the Eckert number, the number density of dust particles, and the heat source/sink parameter on velocity and temperature profiles are shown in several plots. The effects of the wall temperature gradient function and the wall temperature function are tabulated and discussed.

关键词： heat transfer boundary layer flow stretching surface dusty fluid viscousdissipation non-uniform heat source numerical solution

The ruminal microbiome associated with methane emissions from ruminant livestock

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journal of Animal Science and Biotechnology 2017年第2期8卷 289-299页

作者： Ilma Tapio Timothy j.Snelling Francesco Strozzi R.john Wallace Green Technology Natural Resources Institute FinlandJokioinenFinland Rowett Institute of Nutrition and Health University of AberdeenForesterhillAberdeen AB16 5BDUK. PTP Via Einstein-Loc.Cascina Codazza26900 Lodiltaly

Methane emissions from ruminant livestock contribute significantly to the large environmental footprint of *** rumen is the principal source of methane, and certain features of the microbiome are associated with low/high methane phenotypes. Despite their primary role in methanogenesis, the abundance of archaea has only a weak correlation with methane emissions from individual animals. The composition of the archaeal community appears to have a stronger effect, with animals harbouring the Methanobrevibacter gottschalki clade tending to be associated with greater methane emissions. Ciliate protozoa produce abundant H_2, the main substrate for methanogenesis in the rumen,and their removal（defaunation） results in an average 11% lower methane emissions in vivo, but the results are not consistent. Different protozoal genera seem to result in greater methane emissions, though community types（A, AB, B and O） did not differ. Within the bacteria, three different ‘ruminotypes＇ have been identified, two of which predispose animals to have lower methane emissions. The two low-methane ruminotypes are generally characterized by less abundant H_2-producing bacteria. A lower abundance of Proteobacteria and differences in certain Bacteroidetes and anaerobic fungi seem to be associated with high methane emissions. Rumen anaerobic fungi produce abundant H_2 and formate, and their abundance generally corresponds to the level of methane emissions. Thus, microbiome analysis is consistent with known pathways for H_2 production and methanogenesis, but not yet in a predictive manner. The production and utilisation of formate by the ruminal microbiota is poorly understood and may be a source of variability between animals.

关键词： Archaea Methane Microbiome Rumen

Anodic Cyclizations, Seven-Membered Rings, and the Choice of Radical Cation *** Pathways

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Chinese journal of Chemistry 2019年第7期37卷 672-678页

作者： Robert j.Perkins Ruozhu Feng Qingquan Lu Kevin D.Moeller Department of Chemistry Washington University in St.Louis St.Louis MO 63130 USA

While many steps in an oxidative cyclization reaction can be important,it is the cyclization step itself that plays the central *** this step does not proceed well,then optimization of the rest of the sequence is *** report here that the key to the cyclization is channeling the reaction down the correct *** reactions require the use of a radical pathway and some require the use of a radical cation *** example of each is provided along with a strategy for accessing both pathways using a common intermediate.

关键词： Anodic Cyclizations Seven-Membered Rings

Permanence and global attractivity of stage-structured predator-prey model with continuous harvesting on predator and impulsive stocking on prey

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Applied Mathematics and Mechanics(English Edition) 2008年第5期29卷 653-663页

作者：焦建军陈兰荪 juan j.Nieto Torres Angela School of Mathematics and Statistics Guizhou College of Finance and Economics Department of Applied Mathematics Dalian University of Technology Department of Mathematical Analysis Faculty of MathematicsUniversity of Santiago de Compostela15782 Santiago de Compostela Spain Department of Psychiatry Radiology and Public Health Faculty of Medicine University of Santiago de CompostelaSpain

We investigate a stage-structured delayed predator-prey model with impulsive stocking on prey and continuous harvesting on predator. According to the fact of biological resource management, we improve the assumption of a predator-prey model with stage structure for predator population that each individual predator has the same ability to capture prey. It is assumed that the immature and mature individuals of the predator population are divided by a fixed age, and immature predator population does not have the ability to attach prey. Sufficient conditions are obtained, which guarantee the global attractivity of predator-extinction periodic solution and the permanence of the system. Our results show that the behavior of impulsive stocking on prey plays an important role for the permanence of the system, and provide tactical basis for the biological resource management. Numerical analysis is presented to illuminate the dynamics of the system.

关键词： stage-structured, impulsive stocking continuous harvesting global attractivity permanence

The Suspended Sediment Concentration Distribution in the Bohai Sea,Yellow Sea and East China Sea

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journal of Ocean University of China 2013年第3期12卷 345-354页

作者： BIAN Changwei jIANG Wensheng Richard j.Greatbatch DING Hui Physical Oceanography Laboratory Ocean University of China Helmholtz Centre for Ocean Research at Kiel University (GEOMAR)

The distribution of the suspended sediment concentration （SSC） in the Bohai Sea, Yellow Sea and East China Sea （BYECS） is studied based on the observed turbidity data and model simulation results. The observed turbidity results show that （i） the highest SSC is found in the coastal areas while in the outer shelf sea areas turbid water is much more difficult to observe, （ii） the surface layer SSC is much lower than the bottom layer SSC and （iii） the winter SSC is higher than the summer SSC. The Regional Ocean Modeling System （ROMS） is used to simulate the SSC distribution in the BYECS. A comparison between the modeled SSC and the observed SSC in the BYECS shows that the modeled SSC can reproduce the principal features of tlte SSC distribution in the BYECS. The dynamic mechanisms of the sediment erosion and transport processes are studied based on the modeled results. The horizontal distribution of the SSC in the BYECS is mainly determined by the current-wave induced bottom stress and the fine-grain sediment distribution. The current-induced bottom stress is much higher than the wave-induced bottom stress, which means the tidal currents play a more significant role in the sediment resuspension than the wind waves. The vertical mixing strength is studied based on the mixed layer depth and the turbulent kinetic energy distribution in the BYECS. The strong winter time vertical mixing, which is mainly caused by the strong wind stress and surface cooling, leads to high surface layer SSC in winter. High surface layer SSC in summer is restricted in the coastal areas.

关键词： ROMS model turbidity observation seasonal variation bottom stress vertical mixing

First report on Guanshan Biota(Cambrian Stage 4) at the stratotype area of Wulongqing Formation in Malong County, Eastern Yunnan, China

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Geoscience Frontiers 2019年第4期10卷 1459-1476页

作者： Feiyang Chen Zhifei Zhang Marissa j. Betts Zhiliang Zhang Fan Liu State Key Laboratory of Continental Dynamics Shaanxi Key Laboratory of Early Life and EnvironmentsDepartment of GeologyNorthwest UniversityXi’an 710069China Division of Earth Sciences School of Environmental and Rural ScienceUniversity of New EnglandArmidaleNSW 2351Australia

Exceptionally preserved fossils,such as those from Cambrian Burgess Shale-type fossil-Lagerstatten are critical because of their unique contributions to knowledge of the phylogenetic radiation and palaeoecological expansion of metazoans during the Cambrian ***,these deposits provide information that is usually unobtainable from shelly and skeletonized fossils *** Guanshan Biota(Cambrian Series 2,Stage 4)in the Yunnan Province of South China,has produced abundant and diverse,exquisitely preserved fossils that often retain soft tissues and *** date,most fossils from the Guanshan Biota have been collected from localities such as Gaoloufang and Gangtoucun,which have become inaccessible due to new urban expansions and constructions of residential *** we present the first report of soft bodied fossils from a new section at Kanfuqing,close to the Wulongqing village in Malong County,approximately 3 km east of the Wulongqing Formation stratotype *** retain soft morphology,and include brachiopods with delicate marginal setae,priapulids with well-preserved sclerites and vetulicolians with entire sections of *** addition,this fauna includes rare occurrences of trilobites preserved with soft tissues replicated as pyrite pseudomorphs after *** discovery represents an important palaeogeographical extension of soft-bodied fossils of the Guanshan fauna to the east of the Xiaojiang Fault(related to Tsinning tectonic movements ca.700 Ma).The fauna from the new Kanfuqing section is similar to that reported from the Wulongqing Formation west of the Xiaojiang Fault,and thus has significant implications for early Cambrian palaeogeography,faunal successions and palaeoenvironments of eastern Yunnan.

关键词： Guanshan Biota Early Cambrian Xiaojiang Fault Eastern Yunnan Palaeoenvironment Palaeogeography

Historical relationships of areas of endemism of the Brazilian Atlantic rain forest： a cladistic biogeographic analysis of harvestman taxa （Arachnida： Opiliones）

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Current Zoology 2017年第5期63卷 525-535页

作者： Marcio B. DASILVA Ricardo PINTO-DA-ROCHA juan j. MORRONE Departamento de Sistematica e Ecologia CCEN Universidade Federal da Paraiba Cidade Universitaria Joao Pessoa PB Brazil Departamento de Zoologia Instituto de Biociencias Universidade de Sao Paulo Sao Paulo SP Brazil Museo de Zoologia "Alfonso L. Herrera" Departamento de Biologia Evolutiva Facultad de Ciencias Universidad Nacional Autdnoma de Mexice (UNAM) 04510 Mexico City Mexico

Based on a cladistic biogeographic analysis of 6 species-level phylogenies of harvestman taxa, wesearched for congruence in the historical relationships of 12 areas of endemism of the BrazilianAtlantic Rain Forest. We constructed general area cladograms using Primary Brooks ParsimonyAnajysis （BPA）, BPA of nodes, and paralogy-free subtree analysis. These analyses resulted in 6general area cladograms, that allow to infer a general pattern of the relationships among areas ofendemism from the Brazilian Atlantic Rain Forest. Northern areas resulted related basally showingmain disjunctions at the Doce River Valley and Todos os Santos Bay/S^o Francisco River *** remaining areas of endemism were included in a southern and a southeastern block, sepa-rated by the Ribeira do Iguape Valley. Incongruence Length Differences tests showed no significantincongruence among the resulting cladograms and other matrix partitions. We concluded that tec-tonism and ancient marine transgressions were the probable processes responsible for the maindisjunctions, whereas Neogene refugia seem to have caused the more recent disjunctions. Thegeneral pattern and redundancy in area relationships suggest a model of main reiterative barriersin diversification at multiple times for the evolution of the Atlantic Rain Forest. The renewal of cla-distic biogeography and the search for common biogeographic patterns are discussed.

关键词： dispersal, historical biogeography, Mata Atlantica, speciation, vicariance.

Construction of a hierarchical multiscale conducting network for enhanced thermoelectric response in organic PEDOT:PSS based nanocomposites

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journal of Materiomics 2021年第1期7卷 34-39页

作者： Yong Zhang Siqi Liu j.justin Koh Chaobin He Department of Materials Science and Engineering National University of Singapore9 Engineering Drive 1117575Singapore Institute of Materials Research and Engineering A*STAR(Agency for ScienceTechnology and Research)117602Singapore

Thermoelectric technology,which is characterized by the interconversion between heat and electricity,is demonstrated as an efficient and environmentally friendly route for thermal energy harvesting and solid-state cooling *** pursuit for high-performance room temperature thermoelectric materials is of significant ***,we proposed a design strategy to dramatically improve the thermoelectric response by constructing a hierarchical multiscale conductor network(AgNWs/CNT)in polymer matrix(PEDOT:PSS).At the optimized composition,the highest Seebeck coefficient and electrical conductivity of base treated ternary PEDOT:PSS/AgNWs/CNT composite are optimized to be 58.6μV K^(-1)and~1950 S ***,the power factor is thus calculated to be on the order of 670μV m^(-1)K^(-2),which is among one of the highest values compared with previous *** underlying mechanism is illustrated based on detailed structure,morphology and electron transport *** work affords a novel strategy for the future development of high-performance room temperature nanocomposite thermoelectrics.

关键词： PEDOT:PSS Thermoelectrics Energy harvesting Hierarchical structure Seebeck coefficient

Ectomycorrhizal and Saprotrophic Fungal Communities Vary Across mm-Scale Soil Microsites Differing in Phosphatase Activity

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Pedosphere 2019年第3期29卷 344-359页

作者： Aaron GODIN Denise BROOKS Sue j. GRAYSTON Melanie D. jONES Biology Department University of British Columbia Okanagan campus Kelowna V1V 1V7 (Canada) Department of Forest & Conservation Sciences Faculty of Forestry University of British Columbia Vancouver V6T 1Z4 (Canada)

To understand nutrient cycling in soils, soil processes and microorganisms need be better characterized. To determine whether specific trophic groups of fungi are associated with soil enzyme activity, we used soil imprinting to guide mm-scale sampling from microsites with high and low phosphatase activities in birch/Douglas-fir stands. Study 1 involved sampling one root window per site at 12 sites of different ages(stands);study 2 was conducted at one of the stem-exclusion stands, at which 5 root windows had been installed. Total fungal and ectomycorrhizal(EM) fungal terminal-restriction fragment length polymorphism(TRFLP)fingerprints differed between high-and low-phosphatase activity microsites at 8 of 12 root windows across 12 sites. Where differences were detected, fewer EM fungi were detected in high-than low-phosphatase activity microsites. Using 5 root windows at one site,next-generation sequencing detected similar fungal communities across microsites, but the ratio of saprotrophic to EM fungal reads was higher in high-phosphatase activity microsites in the two windows that had low EM fungal richness. In windows with differences in fungal communities, both studies indicated that EM fungi were less successful than saprotrophic fungi in colonizing fine-scale,organic matter-rich microsites. Fine-scale sampling linked with in situ detection of enzyme activity revealed relationships between soil fungal communities and phosphatase activity that could not be observed at the scales employed by conventional approaches, thereby contributing to the understanding of fine-scale phosphorus cycling in forest soils.

关键词： ectomycorrhizae fine scale fungal communities phosphatase root windows saprotrophic fungi soil imprinting