Influence de la phosphatation au zinc sur la résistance a la corrosion d’un acier au carbone en milieu maring

Zinc phosphatation influence on the resistance to corrosion of a carbonbased steel in marine mediumIn the frame of the present investigation, we have showed that the profile of the cathodic curves of a non phosphated metal, plead in favour to a kinetic profile essentially monitored by a pure diffusion. The corrosion rate, obtained from the cathodic curves as well as by a colorimetrical dosage of the dissolved iron, increases when the rotation speed of the electrode increases. Which show a diffusional control the phosphatation of the electrode does not seem to modify the cathodic curves profile. However the height of the diffusion palier depends on the thickness of the phosphatation layer. It takes values lower than those of an uncovered steel for a layer thickness of two micrometers the phosphatation layer reinforce notably the resistance to the corrosion of the internal layer which is essentially composed with iron oxides, by decreasing the corrosion rate with the increase of the layer. However, the benefical effect of the phosphatation is maximal for a thickness of three micrometers. This effect occurs also during the anodic behaviour

Atomic layer deposition: Low temperature process well adapted to ULSI and TFT technologies

The high k dielectrics is an important materials to be integrate in future Ultra Large Scale Integration (ULSI) and future TFT technology. Indeed, to keep on the Moore\u27s Law curve, the reduction of silicon oxide (SiO2) thickness still required, but this reduction is hindered by tunneling current leakage limit. Consequently, it is important to replace SiO2 by another materials with high dielectric constant. The use of this material in manufacturing of gate dielectric in Thin-film transistor (TFT) and in Complementary Metal Oxide Semiconductor (CMOS) will increase gate capacitance with maintaining a low leakage current. Titanium dioxide is a good candidate due to its high dielectric constant in its rutile crystalline phase (180).This rutile structure is obtained at low temperature (250°C) by ALD deposition when TiO2 is deposited on ruthenium dioxide (RuO2) layer thanks to the small lattice mismatch between these two materials

A Numerical Simulation Approach for Sunspot Area Calculation

The aim of this paper is the numerical simulation of the sunspot area (SSA) and its location on the walls and on the floor of a room with a single window facing south. The input parameters of the calculation code are the geometry of the cell located in the site of Ksar Challala (35.1 N, 2.19 E, 800 m) in Algeria for the 21st of March, June and December. The SSA is a function of the window’s area, the date and time, the orientation of the room, the altitude and the azimuth of the sun. The obtained results show that the western wall is affected by the sun in the morning, the eastern wall in the afternoon, the floor and the north wall in the middle of the day. By increasing the window area from 1 m2 to 2 m2 we found that the SSA increases considerably

Mode - Modalité (linguistique)

Ces notions, issues de la tradition grammaticale occidentale et fortement réinvesties par la linguistique moderne, sont à la fois essentielles et très polysémiques, avec des définitions, des approches et des objets mêmes extrêmement divers selon les périodes et les courants théoriques. On renverra sur ce sujet aux grands outils francophones de la linguistique, notamment : Marouzeau (p. 147, sous « Modal » et « Mode ») ; Mounin : (p. 147, sous « Mode » et « Modal ») ; Dubois et al. (p. 319-321..

Kerkur

Ce terme, d’origine berbère mais largement passé en arabe dialectal (surtout au Maroc, avec vélo-pharyngalisation des « r » : [keṛkûṛ]), désigne les tas de pierres constitués par les voyageurs et pèlerins en certains lieux caractéristiques, à forte charge symbolique : cols, croisements de chemins, lieux où a été commis un crime... Le voyageur, pour conjurer le mauvais sort et/ou les forces maléfiques qui habitent le lieu, jette ou dispose un/des caillou(s) supplémentaire (s). Ce rite, déjà pr..

Laser-fabricated porous alumina membranes (LF-PAM) for the preparation of metal nanodot arrays

We report on an efficient photonic-based method to prepare nanodot array of functional materials, independently of the nature of the substrate.Comment: Small (2008) Accepte

The genetic basis of thyroid function: Novel findings and new approaches

Context: Genetic factors are major determinants of thyroid function. Over the last two decades,multiple genetic variants have been associated with variations in normal range thyroid functiontests. Most recently, a large-scale genome-wide association study (GWAS) doubled the number ofknown variants associated with normal range thyrotropin (TSH) and free thyroxine (FT4) levels.Evidence Acquisition: This review summarizes the results of genetic association studies onnormal range thyroid function and explores how these genetic variants can be used in futurestudies to improve our understanding of thyroid hormone regulation and disease.Evidence Synthesis: Serum TSH and FT4 levels are determined by multiple genetic variantson virtually all levels of the hypothalamus-pituitary-thyroid (HPT) axis. Functional followup studies on top of GWAS hits has the potential to discover new key players in thyroidhormone regulation, as exemplified by the identification of the thyroid hormone transporterSLC17A4 and the metabolizing enzyme AADAT. Translational studies may use these geneticvariants to investigate causal associations between thyroid function and various outcomes inMendelian Randomization (MR) studies, to identify individuals with an increased risk of thyroiddysfunction, and to predict the individual HPT axis setpoint.Conclusions: Recent genetic studies have greatl

Beni Snous

Extrait de Géographie de l’Afrique du Nord-Ouest (J. Despois et A. Raynal) Le groupe berbérophone des Beni Snous occupe la Ghaba occidentale, c’est-à-dire l’ensemble des plateaux calcaires de la Haute Tafna à l’ouest-sud-ouest de Tlemcen. La Ghaba est un milieu rude : suffisamment arrosé dans son ensemble (600 à 700 mm) mais froid, avec 10 à 20 chutes de neige par an, des gelées nombreuses, parfois de longues périodes sèches et du siroco. La forêt est plus utile comme pâturage que comme fourn..

Reliability centered maintenance optimization for power distribution systems

a b s t r a c t Today's electricity distribution systems operate in a liberalized market. These systems should therefore be able to provide electricity to customers with a high degree of reliability and be cost-effective for suppliers. RCM (Reliability Centred Maintenance) was invented by the aircraft industry in the 1960s, to organize the increasing need for maintenance for reducing costs without reducing b safety. Today RCMmethods invented by ALADON [1] are seen as very complex and are not fully accepted by the Algerian power industry. The extensive need of human and capital resources in the introduction phase is also a negative factor that could be one of the reasons of why RCM methods are not used in our branch. This article provides a discussion of the two primary objectives of RCM: to ensure safety through preventive maintenance actions, and, when safety is not a concern, preserve functionality in the most economical manner. For the power distribution systems facilities, the mission should be considered at the same level as safety