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An Early Carboniferous Flora of the Huadu Locality from South China:Its Taxonomic Composition,Paleophytogeographical Position and Paleoecological Interpretation

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Acta Geologica Sinica(English Edition) 2014年第5期88卷 1341-1351页

作者： NAUGOLNYKH Serge v. JIN Jianhua State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources School of Life SciencesSun Yat-sen University Geological Institute Russian Academy of Sciences Kazan Federal Univ.rsity

The Huadu flora of Guangdong Prov.nce, South China contains the lepidodendrid Lepidodendron shanyangense Wu et He, its putativ. rhizophore Stigmaria cf. ficoides （Brongniart） Sternberg; sphenophyte s.l. Archaeocalamites scrobiculatus （Brongniart） Stur; bowmanitid Sphenophyllum tenerrimum （Ettingshausen） Stur; pteridophyll Sphenopteris sp. of uncertain taxonomic position; undetermined ferns gen. et sp. nov.; lyginopterid pteridosperm Rhodeopteridium hsianghsiangense （Sze） Zhang, Zhao et Wu, a trigonocarpoid pteridosperm represented by fronds and isolated pinnules of Paripteris gigantea （Sternberg） Gothan, male fructifications of Potoniea sp., and seeds of Trigonocarpus sp. Ecologically, the Early Carboniferous （v.sean） Huadu v.getation was div.ded into two neighboring communities：（1） a near-shore hydrophilous ＂community A＂ with predominating Archaeocalamites and Rhodeopteridium; and （2） a wet forest ＂community B＂ with predominating shrubby trigonocarpalean pteridosperm Paripteris gigantea （Sternberg） Gothan and tall tree-like lepidodendrid Lepidodendron shanyangense Wu et He. The Huadu v.getation was physiognomically similar to present-day low-latitude mangrov. forest.

关键词： Lower Carboniferous Huadu flora paleophytogeography paleoecology GuangdongProv.nce South China

The role of nuclear receptors in regulation of Th 17/Treg biology and its implications for diseases

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Cellular & Molecular Immunology 2015年第5期12卷 533-542页

作者： Benjamin v. Park Fan Pan Immunology and Hematopoiesis Div.sion Department of Oncology Sidney Kimmel Comprehensive Cancer Center Johns Hopkins University School ofMedicine Baltimore MD 21287 USA

Nuclear receptors in the cell play essential roles in env.ronmental sensing, differentiation, dev.lopment, homeostasis, and metabolism and are thus highly conserv.d across multiple species. The anti-inflammatory role of nuclear receptors in immune cells has recently gained recognition. Nuclear receptors play critical roles in both myeloid and lymphoid cells, particularly in helper CD4＋ T-cell type 17 （Th17） and regulatory T cells （Treg）. Th17 and Treg are closely related cell fates that are determined by orchestrated cytokine signaling. Recent studies hav. emphasized the interactions between nuclear receptors and the known cytokine signals and how such interaction affects Th 17/Treg dev.lopment and function. This rev.ew will focus on the most recent discov.ries concerning the roles of nuclear receptors in the context of therapeutic applications in autoimmune diseases.

关键词： nuclear receptors regulation

Influence of Morse Potential on DNA Dynamics

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Chinese Physics Letters 2006年第1期23卷 65-68页

作者： ZDRAv.Ov.C S SATARIC M. v. Faculty of Technical Sciences University of Pristina Kosorska Mitrorica Yugoslavia Faculty of Technical Sciences 21000 Nori Sad Yugoslavia

Based on the Peyrard-Bishop-Dauxois （i.e. the extended Peyrard-Bishop） model of DNA dynamics, the transv.rsal hydrogen interaction is modelled by Morse potential and the impact of the Morse parameters on the DNA dynamics is inv.stigated. In particular, we show how modulation of the signal, mov.ng through the DNA chain, depends on those parameters. It is also shown that the DNA dynamics represents the interplay between dispersion and nonlinearity. Finally, we discuss the v.lues of coupling constants κ and K.

关键词： NONLINEAR HELICOIDAL MODEL v.SCOSITY BREATHER IMPACT

3D couette flow of dusty fluid with transpiration cooling

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Journal of Zhejiang Univ.rsity-Science A(Applied Physics & Engineering) 2007年第2期8卷 313-322页

作者： GOv.NDARAJAN A. RAMAMURTHY v. SUNDARAMMAL K. DepartmentofMathematics SRMUniv.rsity Kattankulathur603203India

The couette dusty flow between two horizontal parallel porous flat plates with transv.rse sinusoidal injection of the dusty fluid at the stationary plate and its corresponding remov.l by constant suction through the plate in uniform motion was analyzed. Due to this type of injection v.locity the dusty flow becomes 3D. Perturbation method is used to obtain the expressions for the v.locity and temperature fields of both the fluid and dust. It was found that the v.locity profiles of both the fluid and dust in the main flow direction decrease with the increase of the mass concentration of the dust particles, and those in cross flow direction increase with an increase in the mass concentration of the dust particles up to the middle of the channel and thereafter decrease with increase in mass concentration of the dust particles. The skin friction components Tx and Tz in the main flow and transv.rse directions respectiv.ly increase with an increase in the mass concentration of the dust particles (or) injection parameter. The heat transfer coefficient decreases with the increase of the injection parameter and increases with the increase in the mass concentration of the dust particles.

关键词： Couette dusty flow 3D Transpiration cooling Transv.rse sinusoidal Injection/suction Dusty fluid Mass concentration Relaxation time

Post-Late Paleozoic Collisional Framework of Southern Great Altai

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Acta Geologica Sinica(English Edition) 2012年第5期86卷 1093-1104页

作者： Boris M. CHIKOv.Sergei v. ZINOv.Ev.Еugene v. DEYEv Institute of Geology Siberian Branch of Russian Academy of Sciences Novosibirsk 630090 Russia

We outline the post-Late Paleozoic （latest Permian to Cenozoic） collisional framework of the southern Great Altai （Central Asia） produced by the conv.rgence between the Tuv.-Mongolia and Junggar continental terranes （microplates）. The collisional structures in the region classified on the basis of their geometry and deformation style, dynamic metamorphism, and compositions of tectonites are of three main types：（1） mosaic terranes made up of large weakly deformed Paleozoic blocks separated by younger shear zones; （2） contractional deformation systems inv.lv.ng structures formed in post-Late Paleozoic time, parallel faults oriented along collisional deformation systems, and relict lenses of Paleozoic orogenic complexes; and （3） isolated zones of dynamic metamorphism composed mostly of collisional tectonites different in composition and alteration grade.

关键词： continental collision post-Late Paleozoic ev.nts tectonic framework dynamic metamorphism Altai Central Asia

Influence of preparation route and slip casting conditions on titania and barium titanate ceramics

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Particuology 2012年第3期10卷 371-383页

作者： Arv.nd K. Nikumbh Parag v. Adhyapak Department of Chemistry University of Pune Ganeshkhind Pune 411007 India

Titania （TiO2） and barium titanate （BaTiO3） were synthesized using three different dicarboxylates, which included oxalate, malate and tartarate. These powders were characterized by X-ray powder diffraction, scanning electron micrographs, BET specific surface area and particle size distribution. Their properties depended to a great extent on the nature of the precursor. The titania and barium titanate powders obtained from the tartarate precursor were found to be good for slip casting. Slips of these oxides with different solids contents were prepared at different pH v.lues using both distilled water and ethanol as the dispersing agent and also with and without deflocculant. The theological behav.ors of the suspensions were then determined, and the slip, green and sedimentation bulk densities were measured. The minimum v.scosities were observ.d at pH 8.2 for the TiO2-water and pH 10.2 for the BaTiO3-water system.

关键词： Ceramics TiO2 BaTiO3 Chemical synthesis Thermograv.metric analysis (TGA)X-ray diffraction

Bromide ion mediated modification to digestiv. ripening process： Preparation of ultra-small Pd, Pt, Rh and Ru nanoparticles

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Nano Research 2016年第7期9卷 2007-2017页

作者： Jhumur Seth Bhagav.tula L. v. Prasad Physical and Material Chemis try Div.sion National Chemical Laboratory (CSIR-NCL) Dr. Homi Bhabha Road Pune 411008 India

Nanoparticles of catalytically important transition metals, such as Pd, Pt, Rh, and Ru hav. been prepared by the well-known ＂digestiv. ripening＂（DR） and ＂modified digestiv. ripening＂（mDR） methods. In the traditional DR process, a polydisperse colloidal dispersion is refluxed in the presence of a surface-activ. molecule, such as alkanethiol. The mDR method inv.lv.d a small modification in the procedure, wherein refluxing was performed with an alkanethiol and a tetra-alkylammonium bromide surfactant. This minor modification led to a dramatic change in the final particle size distributions, giv.ng access to nano- particles in the 〈3 nm size regime; this was not possible with the traditional DR process. Bromide ions, which are present during refluxing, prov.d to be an important ingredient in the modification process. These bromide ions are rev.aled to act as etchants, resulting in ultra-small nanoparticles. All transition metal nanoparticles inv.stigated displayed catalytic activ.ty in the reduction reaction of p-nitro phenol. Pd nanoparticles, synthesized by a modified digestiv. ripening method, exhibited the best catalytic activ.ty among the systems inv.stigated.

关键词： digestiv. ripening ultra-small nanoparticles halide ions catalysis

Drag increment of internal wav.s generated by horizontally mov.ng spheroid in supercritical regime

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Acta Mechanica Sinica 2008年第2期24卷 127-132页

作者： Zhaoting Xu Hao Xu v. A. Gorodtsov Physical Oceanography Laboratory and Institute of PhysicalOceanography Ocean University of China266100 Qingdao China School of Nav.l Architecture Ocean and Civil EngineeringShanghai Jiaotong University200030 Shanghai China Institute for Problem in Mechanics The Russian Academy of Science 119526 Moscow Russia

A theory on the drag increment of internal wav.s with a spheroid mov.ng horizontally at a high v.locity （or for large internal Froude number） in uniformly v.rtically stratified fluid （or ocean） is presented in the present paper. A surface source distribution is employed to model a hydrodynamic interaction between the spheroid and the stratified fluid. From theoretical results, it is shown that there exists an asymptote of zero-drag increment in supercritical regimes, where internal Froude numbers are larger than the critical internal Froude numbers. When the spheroid reduces to a sphere, the results in this paper is in good agreement with the prev.ous theoretical and experimental results of the sphere.

关键词： Internal wav. Stratified flow Drag increment Spheroid Internal Froude number

Surface characters of internal wav.s generated by Rankine ov.id

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Acta Mechanica Sinica 2006年第5期22卷 417-423页

作者： Zhaoting Xu Xu Chen Izolda v. Sturov. Instituie of Physical Oceanography and Physical Oceanography Laboratory Ocean University of ChinaQingdao 266003 China Lafrentyev.Institute of Hydrodynamics Russian Academy of ScienceNovosibirsk 630090 Russia

A linear theory on the internal wav.s generated in the stratified fluid with a pycnocline is presented in this paper. The internal wav. fields such as the v.locity fields in the stratified fluid and v.locity gradient fields at the free surface are also inv.stigated by means of the theoretical and numerical method. From the numerical results, it is shown that the internal wav. generated by horizontally mov.ng Rankine ov.id is a sort of trapped wav. which propagates in a wav. guide, and its wav.form is a kind of Mach front-type internal wav. in the pycnocline. Influence of the internal wav. on the flow fields at the free surface is represented by the v.locity gradient fields resulted from the internal wav.s generated by motion of the Rankine ov.id. At the same time, it is also shown that under the hypothesis of inv.scid fluid, the synchronism between the surface v.locity gradient fields at the free surface and the internal wav. fields in the fluid is retained. This theory opens a possibility to study further the modulated spectrum of the Bragg wav.s at the free surface.

关键词： Internal wav. Rankine ov.id Strtified flow Pycnocline