Search

The ability of polymeric nanoparticles to promote glass bead and pentlandite (Pn, nickel sulfide mineral) attachment to air bubbles in flotation was measured as a function of the nanoparticle glass transition temperature using six types of nanoparticles based on styrene/N-butylacrylate copolymers. Nanoparticle size, surface charge density, and hydrophobicity were approximately constant over the series. The ability of the nanoparticles to promote air bubble attachment and perform as flotation collectors was significantly greater for softer nanoparticles. We propose that softer nanoparticles were more firmly attached to the glass beads or mineral surface because the softer particles had a greater glass/polymer contact areas and thus stronger overall adhesion. The diameters of the contact areas between polymeric nanoparticles and glass surfaces were estimated with the Young–Laplace equation for soft, liquidlike particles, whereas JKR adhesion theory was applied to the harder polystyrene particles. The diameters of the contact areas were estimated to be more than an order of magnitude greater for the soft particles compared to harder polystyrene particles.

L’étude MATURE a évalué l’efficacité, la sécurité, la tolérance et la pharmacocinétique de l’auto-injecteur (AI) 2mL de sécukinumab 300mg chez les patients atteints de psoriasis en plaques modéré à sévère. Nous rapportons ici les résultats de l’analyse du critère principal jusqu’à la semaine 16.

The development of purple blotch of garlic in farmers' fields was studied in conjunction with surveys of fungicide use and other practices in the Chiangmai-Lamphun valley, Northern Thailand. Purple blotch was consistently more severe, and effective fungicide applications most needed, when garlic had been planted early by omitting the normally preceding rice crop. Fungicide use was found to be widespread with a great variety of products encountered, several of which were unsuitable or had not been tested against purple blotch. This reflects erratic marketing of fungicides and lack of consistent extension activities. Fungicide use was not always related to the need to control purple blotch. Furthermore, few farmers used fungicides effectively where needed, because they were hardly aware of the factors affecting efficacy of applications, such as timing of applications, rates and weather conditions.