Cultivo da amora-preta.

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Résistance globulaire des hématies bovines

Une analyse de la résistance globulaire a été menée en exposant des globules rouges de zébus, taurins Baoulé et métis taurins x zébus à diverses concentrations salines. Les résultats statistiques n'ont montré aucune influence du sexe pour toutes les races. Chez les zébus, il y a une différence selon le type d'hémoglobine concerné. Ces derniers différent aussi des taurins et des métis. Le traitement des données a été réalisé en calculant la moyenne du pourcentage d'hémolyse pour tous les échantillons, ainsi qu'avec la concentration de NaCl correspondant à une hémolyse 50 p. 100. Ces différences peuvent donner une explication partielle de l'anémie dans les trypanosomoses bovines à Trypanosoma vivax ou T. congolense, moins prononcée chez les taurins Baoulé que chez les zébu

Ocorrência e danos de Eulechriops rubi (Coleoptera: Curculionidae) na cultura da amora-preta.

O cultivo da amora-preta (Rubus spp.) na Região Sul do Brasil vem crescendo de forma expressiva nos últimos anos, com destaque para os municípios de Campestre da Serra e Vacaria, principais produtores da fruta no Estado do Rio Grande do Sul (Pagot, 2006). A cultura é considerada uma alternativa econômica para viabilizar a pequena propriedade rural de base familiar, devido a características específicas, como cultivo em pequenas áreas e emprego intensivo de mão-de-obra. A maioria dos produtores da fruta emprega tecnologias compatíveis com o sistema orgânico de produção (Brasil, 2004).Informativo Técnico

Positron unveiling high mobility graphene stack interfaces in Li-ion cathodes

Carbon-based coatings in Li-ion battery cathodes improve electron conductivity and enable rapid charging. However, the mechanism is not well understood. Here, we address this question by using positrons as non-destructive probes to investigate nano-interfaces within cathodes. We calculate the positron annihilation lifetime in a graphene stack LiCoO2 heterojunction using an ab initio method with a non-local density approximation to accurately describe the electron-positron correlation. This ideal heterostructure represents the standard carbon-based coating performed on cathode nanoparticles to improve the conduction properties of the cathode. We characterize the interface between LiCoO2 and graphene as a p-type Schottky junction and find positron surface states. The intensity of the lifetime component for these positron surface states serves as a descriptor for positive ion ultra-fast mobility. Consequently, optimizing the carbon layer by enhancing this intensity and by analogizing Li-ion adatoms on graphene layers with positrons at surfaces can improve the design of fast-charging channels.Carbon layers in Li-ion battery cathodes are important for fast charging but the underlying mechanism is still not well understood. Here, ab initio calculations of the positron annihilation lifetime in graphene stack LiCoO2 heterojunction gives insights into ultra-fast ion mobility

Propargyl carbamate-functionalized Cu(II)-metal organic framework after reaction with chloroauric acid: An x-ray photoelectron spectroscopy data record

A copper-containing metal organic framework was prepared using the new organic linker 5-(2-{[(prop-2-yn-1-yloxy)carbonyl]-amino} ethoxy)isophthalic acid [1,3-H2YBDC (where Y = alkYne and BDC = Benzene DiCarboxylate)] and functionalized with gold particles by reaction with HAuCl4 under thermal treatment in methanol. The resulting system was investigated by complementary techniques to obtain information on its structure and morphology. In the present work, x-ray photoelectron spectroscopy (XPS) was employed to analyze the chemical composition of a representative specimen. Besides wide scan spectra, data obtained by the analysis of the C 1s, O 1s, N 1s, Cu 2p, and Au 4f signals are presented and critically discussed. The results highlight the reduction of Au(III) to mostly Au(I) species. Overall, the data presented herein may act as useful guidelines for the eventual tailoring of material properties and their possible implementation toward functional applications in heterogeneous catalysis

Growth of NiO thin films in the presence of water vapor: insights from experiments and theory

NiO-based thin films and nanomaterials are promising candidates for a variety of end-uses, encompassing photo- and electrocatalysts, solar cells, displays, and sensors. This widespread attention has strongly fueled the interest in the fabrication of tailored systems featuring modular chemico-physical properties as a function of the required application. In this study, a single-step chemical vapor deposition (CVD) route for the preparation of pure and fluorine-doped NiO films is presented. Growth experiments were performed under water vapor-containing oxygen atmospheres from a series of Ni(II) β-diketonate–diamine molecular precursors featuring a different fluorination degree of the ligand side chain. A comprehensive experimental and theoretical investigation yielded valuable insights into the growth mechanism, with particular regard to the dependence of the system electronic properties on fluorine doping and content, and to the role exerted by water vapor in the reaction atmosphere. In fact, the interactions of water with the diketonate ligands contribute to weaken Ni–O bonds, favoring precursor activation. The obtainment of F-doped NiO systems from fluorinated derivatives and the simplicity of our process make the adopted strategy a valuable tool to control the system characteristics for a variety of eventual functional applications

Des possibilités d'emploi du sperme de taureau transporté de France pour l'insémination artificielle dans les territoires d'Outre-mer

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