检索结果-南通市图书馆

Theoretical and numerical investigation of HF elastic wave propagation in two-dimensional periodic beam lattices

Acta Mechanica Sinica 2013年第6期29卷 783-798页

作者： B.Tie B.Y.Tian D.Aubry laboratory mssmat(UMR-CNRS 8579) Ecole Centrale ParisGrande Voie des Vignes92295 Chatenay-Malabry CedexFrance

The elastic wave propagation phenomena in two-dimensional periodic beam lattices are studied by using the Bloch wave transform. The numerical modeling is applied to the hexagonal and the rectangular beam lattices, in which, both the in-plane （with respect to the lattice plane） and out-of-plane waves are considered. The dispersion relations are obtained by calculating the Bloch eigenfrequencies and eigenmodes. The frequency bandgaps are observed and the influence of the elastic and geometric properties of the primitive cell on the bandgaps is studied. By analyzing the phase and the group velocities of the Bloch wave modes, the anisotropic behaviors and the dispersive characteristics of the hexagonal beam lattice with respect to the wave prop- agation are highlighted in high frequency domains. One im- portant result presented herein is the comparison between the first Bloch wave modes to the membrane and bend- ing/transverse shear wave modes of the classical equivalent homogenized orthotropic plate model of the hexagonal beam lattice. It is shown that, in low frequency ranges, the homog- enized plate model can correctly represent both the in-plane and out-of-plane dynamic behaviors of the beam lattice, its frequency validity domain can be precisely evaluated thanks to the Bloch modal analysis. As another important and original result, we have highlighted the existence of the retro- propagating Bloch wave modes with a negative group veloc- ity, and of the corresponding ＂retro-propagating＂ frequency bands.

关键词： Elastic wave propagation Periodic beam lattice Bloch wave theory Bandgaps Anisotropy Disper- sion relation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Imperfect pitchfork bifurcation in asymmetric two-compartment granular gas

引用

Chinese Physics B 2013年第5期22卷 44-48页

作者：张因李寅阊刘锐崔非非 Pierre Evesque 厚美瑛 Beijing National laboratory for Condensed Matter Physics and CAS Key laboratory of Soft Matter Physics Institute of PhysicsChinese Academy of Sciences Department of Physics Beijing Institute of Technology laboratory mssmat UMR 8579 CNRSEcole Centrale Paris

The clustering behavior of a mono-disperse granular gas is experimentally studied in an asymmetric two-compartment setup. Unlike the random clustering in either compartment in the case of symmetric configuration when lowering the shaking strength to below a critical value, the directed clustering is observed, which corresponds to an imperfect pitchfork bifurcation. Numerical solutions of the flux equation using a modified simple flux function show qualitative agreements with the experimental results. The potential application of this asymmetric structure is discussed.

关键词： compartmentalized granular gases directed clustering imperfect pitchfork bifurcation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Breakdown of Energy Equipartition in Vibro-Fluidized Granular Media in Micro-Gravity

引用

Chinese Physics Letters 2012年第7期29卷 160-163页

作者： CHEN Yan-Pei Pierre Evesque HOU Mei-Ying Key laboratory of Soft Matter Physics Beijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 100190 Lab mssmat Ecole Centrale de ParisUMR 8579 CNRS92295 Châtenay-Malabry CedexFrance

We present a micro-gravity experimental study of intermediate number density vibro-fluidized inelastic spheres in a rectangular *** velocity distributions are investigated,and are found to deviate measurably from a symmetric distribution for the velocity component of the vibrating direction when dividing particles along the vibration direction into several *** feature does not exist in the molecular *** further study the hydrodynamic profiles of pressures p and temperatures T in positive and negative components,such as p+y and p-y and T+y and T-y,in accordance with the sign of velocity components of the vibrating *** vibration direction,granular media are found to be not only inhomogeneous and anisotropic,but also different greatly in positive and negative *** equipartition breaks down in this case.

关键词： partition vibrating dividing

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Understanding of selective oxidation of Fe-Mn binary alloys during continuous annealing through X-ray photoelectron spectroscopy

引用

Corrosion Communications 2023年第3期11卷 72-82页

作者： L.Gong D.Alamarguy N.Ruscassier P.Haghi-Ashtiani M.-L.Giorgi LGPM Centrale Supélec Université Paris Saclay Key laboratory of Advanced Materials of Ministry of Education School of Materials Science and Engineering Tsinghua University Gee PS Centrale Supélec Université Paris Saclay mssmat CNRS Centrale Supélec Université Paris Saclay

Selective oxidation of Fe-Mn alloys was characterizied through X-ray photoelectron spectroscopy and scanning/transmission electron microscopy during industrial continuous annealing（in an atmosphere of N2-5 vol.%H2with traces of water at 800 ℃）.After annealing,only MnO oxides are formed on and below the surface and few iron oxides appear on the top surface due to oxidation of ambient air or the formation of FeO-MnO solid *** concentration profiles exhibit typical selective oxidation and show similar *** concentration first increases to a peak value at a depth of 5-10 nm from surface,and then decreases to the minimum at the oxidation front,following with a floating up and down to bulk *** to XPS spectra and Mn concentration profiles as a function of depth,the annealed alloy surfaces can be divided into four zones:ambient air contaminated zone,MnO enrichment zone（external and internal oxidation coexisting here）,Mn depletion zone and bulk composition *** concentration reaches a minimum value at the oxidation front,whose position is deeper with annealing temperature and time *** value of Mn diffusion coefficient in ferrite estimated using diffusion flux at the oxidation front is 2.9 × 10-15m2s-1at 800℃,which is slightly greater than that in literature.

关键词： Selective oxidation X-ray photoelectron spectroscopy Concentration profile Oxidation front Diffusion coefficient

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Sclareol and linalyl acetate are produced by glandular trichomes through the MEP pathway

引用

Horticulture Research 2021年第1期8卷 2949-2961页

作者： Camille Chalvin Stephanie Drevensek Françoise Gilard Caroline Mauve Christel Chollet Halima Morin Edith Nicol Eva Heripre Lucie Kriegshauser Bertrand Gakiere Michel Dron Abdelhafid Bendahmane Adnane Boualem Universite Paris-Saclay CNRSINRAEUniv EvryInstitute of Plant Sciences Paris-Saclay(IPS2)91405 OrsayFrance Molecular Chemistry laboratory(LCM) UMR 9168CNRSEcole PolytechniqueInstitut Polytechnique de ParisRoute de Saclay91128 Palaiseau CedexFrance laboratory of Mechanics of Soils Structures and Materials(MSSMAT)UMR 8579CNRSEcole CentraleSupelecUniversite Paris-SaclayBâtiment Eiffel8-10 rue Joliot-Curie91190 Gif-Sur-YvetteFrance

Sclareol,an antifungal specialized metabolite produced by clary sage,Salvia sclarea,is the starting plant natural molecule used for the hemisynthesis of the perfume ingredient *** is mainly produced in clary sage flower calyces;however,the cellular localization of the sclareol biosynthesis remains *** elucidate the site of sclareol biosynthesis,we analyzed its spatial distribution in the clary sage calyx epidermis using laser desorption/ionization mass spectrometry imaging(LDI–FTICR-MSI)and investigated the expression profile of sclareol biosynthesis genes in isolated glandular trichomes(GTs).We showed that sclareol specifically accumulates in GTs’gland cells in which sclareol biosynthesis genes are strongly *** next isolated a glabrous beardless mutant and demonstrate that more than 90%of the sclareol is produced by the large capitate *** experiments,using 1-13 C-glucose,and specific enzyme inhibitors further revealed that the methylerythritol-phosphate(MEP)biosynthetic pathway is the main source of isopentenyl diphosphate(IPP)precursor used for the biosynthesis of *** findings demonstrate that sclareol is an MEP-derived diterpene produced by large capitate GTs in clary sage emphasing the role of GTs as biofactories dedicated to the production of specialized metabolites.

关键词： oxide. starting synthesis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：