Composés alicycliques à carbone quaternaire III.‐Oxydation de quelques dérivés gem cyclohexaniques par l'oxygéne, sous U‐V

Les cyclanes dépourvus de carbone tertiaire: le cyclohexane (I), le 1,1‐diméthylcyclohexane (II), le 1,1,3,3‐tétraméthylcylohexane (III), le 1,1,3‐triméthyl‐3‐éthylcyclohexane (IV) et le 1,1,3‐triméthyl‐3‐isopropylcyclohexane (V) ont été oxydés, les dérivés gem pour la première fois, par l'oxygène moléculaire et sous U‐V, respectivement à 70° (I), 110° (II) et 120° (III, IV et V). Tous fournissent du méthanal (polyoxyméthylénes) à cǒté d'un mélange complexe d'acides. Ceux‐ci, ont pu être déterminés, en partie, au départ des cyclanes I et II; I: acides formique, glutarique, valérique et adipique; II: acides formique, diméthyl‐malonique et ß‐ß‐diméthyladipique. La nature de ces dernières substances est en accord avec le mécanisme d'oxydation faisant intervenir, entre autres, une décomposition monomoléculaire de l'hydroperoxyde au niveau du chaînon –O–O–. Copyright © 1955 Wiley‐VCH Verlag GmbH & Co. KGaA, WeinheimSCOPUS: ar.jinfo:eu-repo/semantics/publishe

Density Profile of Terminally Anchored Polymer Chains: A Monte Carlo Study

ABSTRACT: We present results of a detailed Monte Carlo simulation study of a system of a large num-ber of polymer chains terminally anchored or end-grafted on a flat surface. We study this system on a three-dimensional lattice for several different values of the surface coverage and the chain length. We also consider several different distributions for the chain lengths. For monodisperse chains, we find that the monomer density profile shows a depletion layer near the grafting plane in agreement with phenomenolog-ical theories. Beyond this depletion layer, the density profile can be represented by a parabolic form. This result is in agreement with recent self-consistent-field (SCF) calculations rather than with the scaling argu-ments that predict a plateau region for the density profile. The chain-end density is also found to be con-sistent with the SCF calculations; Le., we find that the free ends of the chains are not excluded from region

Synthesis methods of gold nanoparticles for Localized Surface Plasmon Resonance (LSPR) sensor applications

Gold nanoparticles (GNPs) have been known as an excellent characteristic for Local Surface Plasmon Resonance (LSPR) sensors due to their sensitive spectral response to the local environment of the nanoparticle surface and ease of monitoring the light signal due to their strong scattering or absorption. Prior the technologies, GNPs based LSPR has been commercialized and have become a central tool for characterizing and quantifying in various field. In this review, we presented a brief introduction on the history of surface plasmon, the theory behind the surface plasmon resonance (SPR) and the principles of LSPR. We also reported on the synthetization as well of the properties of the GNPs and the applications in current LSPR sensors