Search results for "shape"
showing 10 items of 585 documents
Scientific and technological approaches for sintering and joining of metallic materials by SPS
2013
The flash sintering technique (commonly known as spark plasma sintering, SPS) generates a craze worldwide. This process allows a powder densification from speeds generally 10 to 100 times higher than those of the traditional sintering techniques. In addition, this allows the synthesis of innovative and original dense materials, with a controlled microstructure, complex shapes and, sometimes large sizes. However, the control of scaling and microstructure homogeneity of parts obtained by such a process requires a perfect knowledge of technical equipment including flash sintering to reduce thermal gradients. Modeling is a valuable aid to achieve the improvement of its control. Another potentia…
Stimulated Raman-Spectroscopy of the Q-Branch of Nitrogen at High Pressure - Collisional Narrowing and Shifting in the 150-6800 Bar Range at Room Tem…
1992
0026-8976; The Raman Q branch of N2 has been recorded at room temperature in the pressure range 150-6800 bar, which corresponds to densities from 135 to 800 amagat. In this domain, the Raman Q branch profile is mainly determined by the well-known collisional narrowing. The experimental data have been obtained by means of a high resolution stimulated Raman spectrometer. The linewidth and line shift of the band have been accurately measured as functions of the density, and their density dependences have been fitted by polynomials. The minimum of the linewidth and the maximum of the red shift have been clearly observed at respectively 735.8 and 532.3 amagat. The lineshape was found to be Loren…
Etude théorique de spectres de molécules toupies sphériques à l'aide du formalisme d'ensembles tensoriels irréductibles
2022
Vibrational-rotational spectroscopy of molecules of the spherical top type, in particular, SiH4 and GeH4 molecules, as well as their isotopologues, is of interest in various fields of science and technology, especially in astrophysics and planetology. One of the most important discoveries in the study of the atmospheres of giant planets is the discovery of german and silane gases in the atmospheres of Saturn, Titan, and Jupiter. Despite many years of research on the vibrational-rotational spectra of molecules of german, silane, and their deuterated modifications, many spectral ranges are still unexplored. However, a complete study of the atmospheres of giant planets is possible only in the …
Agroecosystems shape population genetic structure of the greenhouse whitefly in Northern and Southern Europe
2014
International audience; Background: To predict further invasions of pests it is important to understand what factors contribute to the genetic structure of their populations. Cosmopolitan pest species are ideal for studying how different agroecosystems affect population genetic structure within a species at different climatic extremes. We undertook the first population genetic study of the greenhouse whitefly (Trialeurodes vaporariorum), a cosmopolitan invasive herbivore, and examined the genetic structure of this species in Northern and Southern Europe. In Finland, cold temperatures limit whiteflies to greenhouses and prevent them from overwintering in nature, and in Greece, milder tempera…
On invariant measures of finite affine type tilings
2006
In this paper, we consider tilings of the hyperbolic 2-space, built with a finite number of polygonal tiles, up to affine transformation. To such a tiling T, we associate a space of tilings: the continuous hull Omega(T) on which the affine group acts. This space Omega(T) inherits a solenoid structure whose leaves correspond to the orbits of the affine group. First we prove the finite harmonic measures of this laminated space correspond to finite invariant measures for the affine group action. Then we give a complete combinatorial description of these finite invariant measures. Finally we give examples with an arbitrary number of ergodic invariant probability measures.
Physiological properties of some yeast strains
2006
Twenty yeast strains have recently been isolated in pure cultures from natural and industrial sources and identified based mainly on physiological properties. The majority of the strains (15) are alcohologenic belonging to the genus Saccharomyces and comprise two brewer's (beer) yeast strains (S. carlsbergensis= S. uvarum A and B), two baker's yeast strains (S. cerevisiae CA and CP), one spirit yeast strain (S. cerevisiae CF) and ten wine yeast strains (S. cerevisiae var. ellipsoideus = S. ellipsoideus 1, 3, 4, 6, 8 and 9; S. oviformis 2, 5 and 7; and S. uvarum 10). The other 5 yeast strains belong to different species: Kloeckera apiculate, Candida mycoderma (Mycoderma vini), Pichia membran…
El uso de SIG de software libre en una práctica de Biología y Geología de 4º de ESO: los ecosistemas.
2016
Para consolidar el conocimiento del bloque del currículo de Biología y Geología de 4º de la E.S.O. (Educación Secundaria Obligatoria) relacionado con los ecosistemas, hemos desarrollado una metodología docente basada en los Sistemas de Información Geográfica (SIG), en la que el objetivo de los estudiantes es crear un shapefile con atributos espaciales e información ecológica sobre los distintos Parques Nacionales de España mediante su digitalización. Se ejemplifica con el procedimiento concreto del Parque Nacional de Doñana. A través del SIG, con un software gratuito para el centro, se aumenta la interactividad del estudiante con la asignatura, se desarrolla la creatividad y se mejora la ca…
The effect of body shape and gender on wireless Body Area Network on-body channels
2010
Technological advancements have made possible the emergence of Body Area Networks (BANs). There are numerous on-body channel characterizations in the literature performed on a phantom or a single human subject. In this paper, using multiple subjects, we consider the effect of body shape and gender on the on-body channel. A characterization of a narrowband on-body to on-body channel among different subjects is presented. The paper investigates the relationship between the propagation and the subject's physical characteristics. The investigation is performed at 2360 MHz; the new medical band undergoing FCC approval. Our results show that the path loss in women is less than that in men and the…
Review of the relationship between aggregates geology and Los Angeles and micro-Deval tests
2021
Rock aggregates constitute the enormous volume of inert construction material used around the globe. The petrologic description as igneous, sedimentary, and metamorphic types establishes the intrinsic formation pattern of the parent rock. The engineering properties of these rocks vary due to the differences in the transformation process (e.g. hydrothermal deposits) and weathering effect. The two most common mechanical tests used to investigate the performance of aggregates are the Los Angeles (LA) and micro-Deval (MD) tests. This study reviewed the geological parameters (including mineralogy, grain and crystal size, grain shape, and porosity) and the relationship to Los Angeles and micro-De…
Phospholipid distribution in the cytoplasmic membrane of Gram-negative bacteria is highly asymmetric, dynamic, and cell shape-dependent
2020
The cell shape of Gram-negative bacteria is maintained metabolically by asymmetric lipid distribution in biogenic plasma membrane.