375 research outputs found
Nouvelles règles du jeu de billard , rédigées d'après les avis des plus forts joueurs, particulièrement des sieurs Ch...., N...., A...., M..., et publiées par J.-B. Pannetier,...
No full textContient une table des matièresAvec mode text
Coherence between superconducting edge states in superconducting periodic arrays of artificial defects
No full textMagnetic flux penetration process in a superconducting Nb film covered by a lithographic array of ferromagnetic particles
No full textÉtude diffractométrique de l'évolution thermique du sulfate de rubidium de la température ordinaire jusqu'à 800° C
No full textThe variation of the lattice parameters of rubidium sulfate was studied up to 800° C. The caracteristics of the change from orthorhombic to hexagonal symmetry were also studied.
The a parameter increases more than b, and c more than b.
The discontinuities observed for the thermal coefficients for the parameters and the volume show the possible existence of two new low energy transitions at circa 375° C and 575° C and of a new very low energy transition at circa 275° C, besides the polymorphic transition (β ⇆ α) orthorhombic ⇆ hexagonal.L'évolution des paramètres de la forme « basse » température β, orthorhombique, a été suivie jusqu'à la forme haute température α, hexagonale, et, de celle-ci jusqu'à 800° C, bien au-dessus de la température de la transformation polymorphique.
Les caractéristiques du passage de la symétrie orthorhombique à la symétrie hexagonale ont aussi été examinées.
Au cours de cette évolution thermique, une forte anisotropie de dilatation suivant les trois paramètres a été constatée.
En effet, le paramètre a se dilate beaucoup plus que les paramètres b et c, et le paramètre c se dilate plus que le paramètre b.
La discontinuité des valeurs des coefficients de dilatation des paramètres et de dilatation du volume, met en évidence l'existence de trois nouvelles transitions de faibles énergies, situées vers 375° C et 575° C et de très faible énergie située vers 275° C, en plus de la transformation polymorphique (β ⇆ α) orthorhombique [se produisant à]655 ± 2° C hexagonale.Tabrizi Djafar, Pannetier Guy. Étude diffractométrique de l'évolution thermique du sulfate de rubidium de la température ordinaire jusqu'à 800° C. In: Bulletin de la Société française de Minéralogie et de Cristallographie, volume 93, 4, 1970. pp. 437-444
Fret SNCF and wood transport
No full textDans cet article, l'auteur, Marie-Noëlle PANNETIER du Service Fret SNCF de Clermont-Ferrand, partant du constat que la maîtrise des problèmes de transports devient un des enjeux majeurs de la compétitivité des entreprises du bois, examine successivement les modifications nationales et internationales du marché des produits ligneux, l'évolution structurelle des entreprises, ainsi que les répercussions en résultant sur les besoins de transport pour les bois. Elle rappelle ensuite les caractéristiques dominantes de l'offre Fret SNCF — transports massifs, programmés, industriels, sur des grandes distances à l'étranger notamment — ainsi que les aspects spécifiques aux transports des bois : matériel, réseaux, services. Il s'avère que, si ces caractéristiques pouvaient, auparavant, paraître des obstacles au développement du transport des bois par le rail, les évolutions récentes laissent penser que la SNCF peut devenir à court terme un partenaire efficace pour les entreprises de ce secteur. Confiants dans les perspectives d'avenir de ce secteur économique, les responsables commerciaux de Fret SNCF travaillent activement à l'amélioration permanente des services spécialisés pour les bois — amélioration qualitative et quantitative du parc wagons, nouvelle structure tarifaire, renforcement des relations avec les réseaux étrangers, développement de la politique de communication. L'augmentation sensible depuis quelque temps déjà des tonnages de bois transportés par fer atteste bien de la pertinence des mesures déjà mises en place... Il semble donc que, de plus en plus, la filière-bois pourra compter sur Fret SNCF, même en dehors des périodes de chablis.In this article the author, Marie-Noëlle PANNETIER of Fret SNCF of Clermont-Ferrand, starting from the premise that mastering the transport problem is becoming one of the major factors in competition between timber companies, studies in turn the national and international changes in the wood products market, the changes in the structure of companies and the resulting effects on the requirements for wood transport. She then quotes the main features of the Fret SNCF tender — industrial, well-organized, mass transport over large distances, particularly abroad — as well as features specific to wood transport : equipment, communication networks and services. It is affirmed that although these features may in the past have appeared as obstacles to the development of rail transport of wood, recent developments indicate that in the short term SNCF could become a useful partner for businesses in this sector. Confident of the prospects of this economic sector, the commercial managers of Fret SNCF are actively seeking permanent improvements in the specialized services for wood — qualitative and quantitative improvements in goods yards, a new tariff structure, strengthening of relations with foreign rail networks and development of the communication policy. The noticeable recent increases in the tonnage of wood transported by rail shows how apposite the measures already adopted are... It therefore appears that the forest products industries can rely increasingly on Fret SNCF, even outside periods of windthrows
Cristallochimie des sulfates hydratés de terres rares : structure cristalline de sulfate de cérium III tétrahydraté Ce (SO4)3, 4H2O
No full textAccording to single-crystal X-ray diffraction data, crystals of Ce₂ (SO₄)₃•4H₂O are monoclinic, space group P2₁/c. The unit cell with a = 13.390 ± 0.002 Å, b = 7.247 ± 0.001 Å, c = 18.328 ± 0.002 Å, β = 134.20 ± 0.01° contains four formula units. The structure was solved with three-dimensional data by applying Patterson and Fourier techniques. All atoms are located on general positions (4e). Each cerium atom has ninefold coordination in the form of a distorted trigonal prism with three additional ligands. A system of hydrogen bonding is suggested for the water molecules.La diffraction X sur monocristal montre que le sulfate de cérium tétrahydraté Ce₂ (SO₄)₃, 4H₂O est monoclinique (groupe spatial P2₁/c). Les paramètres a = 13,390 ± 0,002 Å, b = 7,247 ± 0,001 Å, c = 18,328 ± 0,002 Å, β = 134,20 ± 0,01° impliquent l'existence de quatre groupements formulaires par maille. Les fonctions de Patterson et les séries de Fourier tridimensionnelles ont permis la détermination de la structure. Tous les atomes sont en position générale (4 e) . Chaque atome de cérium admet une coordinence 9 (prisme trigonal déformé avec trois coordinats supplémentaires). Un schéma de liaisons par pont hydrogène est proposé pour les molécules d'eau.Dereigne André, Manoli Jean-Marie, Pannetier Guy, Herpin Paulette. Cristallochimie des sulfates hydratés de terres rares : structure cristalline de sulfate de cérium III tétrahydraté Ce (SO4)3, 4H2O. In: Bulletin de la Société française de Minéralogie et de Cristallographie, volume 95, 3, 1972. pp. 269-280
Long non-coding RNAs and sex-differentiating genes in bovines
No full textThis study points out new lncRNAs, sex-specific orgonad-specific: the four sex-differentiating genes studied ([i]SOX9, SOX10, FOXL2 and WNT4[/i]) share a [b]bidirectional promoter[/b] with a lncRNA. In the literature, it is described that pervasive transcription around a promoter region could act as a [b]reservoir of RNA polymeraseII[/b], or serve as [b]a barrier to block the spread of repressive chromatin [3].[/b] It is also admitted that non-coding transcripts can influence protein-coding gene expression by reorganizing chromatin structure and recruiting transcriptional co-factors. In our opinion, these lncRNAs transcriptional activity is a way to keep the promoter open and avoid stochastic variation in the expression of the corresponding proten-coding genes. Indeed, in a 60 dpc-fetal gonad, a small variation in sex-differentiating genes expression could lead to developmental sex-disorders like sex-reversal, as it is observed in goats [b][1][/b]. The aim of this work is two-fold. First, to list all the genes that share a bidirectional promotor in order to characterize different protein classes. Second, it aspires to identify all lncRNAs involved intesticular or ovarian differentiation.Using bio-informatics and differential analyses, we want (1) to discriminate ovary-specific from testis-specific lncRNAs and (2) to determine gonad-specific lncRNAs as against PBMC. Then, the comparison of the lncRNAs identified with neighbouring proteine-coding genes will let us highlight new regulatory elements necessary for sex-differentiating genes expression. [u]REFERENCES[/u]: [b][1][/b] Pailhoux [i]et al.[/i], 2001. [i]A 11.7kb-deletion triggers intersexuality and polledness in goats.[/i] Nature Genetics. [b][2][/b] Pannetier [i]et al.[/i], 2012. [i]Telling the story of XX sex-reversal in the goat: Highlighting the sex-crossroad in domestic mammals.[/i] Sexual Development. [b][3][/b] Wei [i]et al.[/i], 2011. [i]Functional consequeces of bidirectional promoters.[/i] Cel
Long non-coding RNAs and sex-differentiating genes in bovines
No full textThis study points out new lncRNAs, sex-specific orgonad-specific: the four sex-differentiating genes studied ([i]SOX9, SOX10, FOXL2 and WNT4[/i]) share a [b]bidirectional promoter[/b] with a lncRNA. In the literature, it is described that pervasive transcription around a promoter region could act as a [b]reservoir of RNA polymeraseII[/b], or serve as [b]a barrier to block the spread of repressive chromatin [3].[/b] It is also admitted that non-coding transcripts can influence protein-coding gene expression by reorganizing chromatin structure and recruiting transcriptional co-factors. In our opinion, these lncRNAs transcriptional activity is a way to keep the promoter open and avoid stochastic variation in the expression of the corresponding proten-coding genes. Indeed, in a 60 dpc-fetal gonad, a small variation in sex-differentiating genes expression could lead to developmental sex-disorders like sex-reversal, as it is observed in goats [b][1][/b]. The aim of this work is two-fold. First, to list all the genes that share a bidirectional promotor in order to characterize different protein classes. Second, it aspires to identify all lncRNAs involved intesticular or ovarian differentiation.Using bio-informatics and differential analyses, we want (1) to discriminate ovary-specific from testis-specific lncRNAs and (2) to determine gonad-specific lncRNAs as against PBMC. Then, the comparison of the lncRNAs identified with neighbouring proteine-coding genes will let us highlight new regulatory elements necessary for sex-differentiating genes expression. [u]REFERENCES[/u]: [b][1][/b] Pailhoux [i]et al.[/i], 2001. [i]A 11.7kb-deletion triggers intersexuality and polledness in goats.[/i] Nature Genetics. [b][2][/b] Pannetier [i]et al.[/i], 2012. [i]Telling the story of XX sex-reversal in the goat: Highlighting the sex-crossroad in domestic mammals.[/i] Sexual Development. [b][3][/b] Wei [i]et al.[/i], 2011. [i]Functional consequeces of bidirectional promoters.[/i] Cel
HIGH RESOLUTION STUDIES OF THE SPECTRA OF GeCl AND SnCl
No full textR. K. Mishra and B. N. Khanna, Ind. J. Pure Appl. Phys. 8, 825 (1970). A. Chatalic, D. Iacocca and G. Pannetier, J, Chim. Phys. 70, 481 (1973).""Author Institution: Institute of Inorganic Chemistry and Metallurgy of Rare Elements, Technical University of Wrocac{\l}awSpectra of GeCl and SnCl were excited in a radio frequency discharge at a low pressure. Bands of the GeCl molecule in the region 335-370 nm have been attributed to the transition on the basis of high resolution studies of the bands at 339.2 and 350.1 nm. The rotational analysis of the (0,0) band of the subsystem has been carried out. The value obtained by the author disagrees with that derived from a rotational analysis of the The (0,0) subbands at 348.6 and 375.8 nm of the system of the SnCl molecule have been recorded at high resolution and analyzed. The rotational constants for the and states have been calculated. The constants calculated by the author agree well with the previous results for the and $substates^{2}
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