Search results for "Elf"
showing 10 items of 5893 documents
Cover Feature: Mannose-Decorated Multicomponent Supramolecular Polymers Trigger Effective Uptake into Antigen-Presenting Cells (ChemBioChem 9/2018)
2018
Buildup of ultrathin multilayer films by a self-assembly process: III. Consecutively alternating adsorption of anionic and cationic polyelectrolytes …
1992
A solid substrate with a positively charged planar surface is immersed in a solution containing an anionic polyelectrolyte and a monolayer of the polyanion is adsorbed. Since the adsorption is carried out at relatively high concentrations of polyelectrolyte, a large number of ionic residues remain exposed to the interface with the solution and thus the surface charge is effectively reversed. After rinsing in pure water the substrate is immersed in the solution containing a cationic polyelectrolyte. Again a monolayer is adsorbed but now the original surface charge is restored. By repeating both steps in a cyclic fashion, alternating multilayer assemblies of both polymers are obtained. The bu…
Non-Centrosymmetric Homochiral Supramolecular Polymers of Tetrahedral Subphthalocyanine Molecules
2015
This is the peer reviewed version of the following article: Angewandte Chemie - International Edition 54.8 (2015): 2543-2547, which has been published in final form at http://dx.doi.org/10.1002/anie.201411272. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving
Long-chain branched ROMP polymers
2009
This article describes the construction of branched ROMP-polymer architectures via polycondensation of ABn-type macromonomers. For this convergent strategy, a polymer was synthesized that carries several hydroxyl-groups along the polymer chain and one carboxylic acid group at the chain end. An esterification reaction between these functional groups yielded long-chain branched polymers. The polymers were analyzed by NMR and SEC to monitor the condensation reaction. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2009
Molecular Parameters of Hyperbranched Polymers Made by Self-Condensing Vinyl Polymerization. 2. Degree of Branching
1997
Using a modified definition, the average degree of branching, , the fraction of branchpoints, , as well as the fractions of various structural units are calculated as a function of conversion of double bonds for hyperbranched polymers formed by self-condensing vinyl polymerization (SCVP) of monomers (or “inimers”) with the general structure AB*, where A is a vinyl group and B* is an initiating group. The results are compared to those for the polycondensation of AB2-type monomers. At full conversion, is somewhat smaller for SCVP ( ∞ ≈ 0.465) than for AB2 systems ( ∞ = 0.5). There are two kinds of linear groups in SCVP whereas there is only one kind in AB2 systems. Since there are two differe…
Multilayer Thin Films by Layer-by-Layer Assembly of Hole- and Electron-Transport Polyelectrolytes: Optical and Electrochemical Properties
2006
In this paper, we pressent the synthesis of a series of p-type and n-type semicondnctring polyelectrolytes with triarylamine, oxadiazole, thiarliazole and triazine moictes. The synthesized polymeric hole and electrom iransport materials were examined optically and electrochemically using UV/Vis spectroscopy. PL spectroscopy and CV. Based on the optical and electrochemical data, each of the energy levels were calculated and all values suggested that the were promising hole-(p-type) or alectron=transprot (n-type) materials for devices. Moreover, the synthesized ionie polymers were suitable for LBL thin film deposition from ditute polymer solutions and the multilayers were fully characterized …
Electrical properties of γ-crosslinked hydrogels incorporating organic conducting polymers
2007
Abstract Hydrogel composites containing nanoparticles of the protonated emeraldine form of polyaniline (PANI-PE) have been synthesised by γ-irradiation, using either polyvinyl pyrrolidone (PVP) or polyvinyl alcohol (PVA) as steric stabilisers. Swelling behaviour of both hydrogels is reported, together with an electrical characterisation of composites, before and after gel network formation, performed by cyclic voltammetry and impedance spectroscopy. Similarities and differences between the two composite systems are discussed.
Inter- and intramolecular non-covalent interactions in 1-methylimidazole-2-carbaldehyde complexes of copper, silver, and gold
2014
Abstract Three new imidazole compounds, [CuBr2(mimc)2] (1), [Ag(mimc)2][CF3SO3] (2), and [AuCl3(mimc)] (3) (mimc = 1-methylimidazole-2-carbaldehyde), have been synthesized, structurally characterized, and further analyzed using the QTAIM analysis. The compounds exhibit self-assembled 3D networks arising from intermolecular non-covalent interactions such as metallophilic interactions, metal-π contacts, halogens–halogen interactions, and hydrogen bonds. These weak interactions have a strong impact on the coordination sphere of the metal atoms and on the packing of compounds 1, 2, and 3.
Effect of natural antioxidants and modified atmosphere packaging in preventing lipid oxidation and increasing the shelf-life of common dolphinfish (C…
2015
We investigated the effects of natural antioxidants and modified atmosphere packaging (MAP) on the quality and shelf-life of Coryphaena hippurus (common dolphinfish) fillets. Fillets of the control group (CO) were simply placed on trays and not sealed. Fillets of the second group (MAP) were preserved in modified atmosphere (45% CO2, 50% N2, 5% O2), and fillets of the third group (MAP-AOX) were preserved by combining natural antioxidants from halophytes with modified atmosphere. All samples were stored in a refrigerator at 1 ± 0.5 C for 18 days. Analyses were conducted at T0 and after 3, 6, 12, 15 and 18 days of storage. According to sensory tests and colour analyses, the fillets in the MAP …
Racemic and Optically Pure Heptahelicene-2-carboxylic Acid: Its Synthesis and Self-Assembly into Nanowire-Like Aggregates (Eur. J. Org. Chem. 5/2011)
2011
The cover picture shows heptahelicene-2-carboxylic acid, whose synthesis and self-assembly are central to the article. The background features Prague's riverbank, which is intermixed with the nanowire-like aggregates of heptahelicene-2-carboxylic acid. The alignment of the swans makes the link between self-assembly and the Prague view. Details are discussed in the article by I. G. Stara, I. Starý, A. Kuhnle et al. on p. 853 ff. Background photo by M. Bělohradský.