Search results for "composite"

A CuIICoII Metallacyclophane-Based Metamagnet with a Corrugated Brick-Wall Sheet Architecture

2004

Modulating the reaction pathway of phenyl diazonium ions using host–guest complexation with cucurbit[7]uril

2022

Aryl diazonium ions are known to be an important intermediate in the divergent synthesis of azo compounds and substituted aromatics. The presence of more than one electrophilic center in a diazonium ion could lead to undesirable side reactions during a synthesis. Herein, we report that the electrophilic α-carbon on a phenyl diazonium [PhN2]+ ion can be selectively deactivated upon host–guest complexation with cucurbit[7]uril (CB7) in aqueous media, achieving a ∼60-fold increase in the half-life of [PhN2]+. Notably, however, the electrophilic nitrogen of the encapsulated diazonium ion remains active towards diazo coupling with strong nucleophiles, allowing the formation of azo compounds usin…

Halloysite nanotubes loaded with peppermint essential oil as filler for functional biopolymer film

2016

Abstract The purpose of this paper is to show how a functional bionanocomposite film with both antioxidant and antimicrobial activities was successfully prepared by the filling of a pectin matrix with modified Halloysite nanotubes (HNT) containing the essential peppermint oil (PO). Firstly, HNT surfaces were functionalized with cucurbit[6]uril (CB[6]) molecules with the aim to enhance the affinity of the nanofiller towards PO, which was estimated by means of HPLC experiments. The HNT/CB[6] hybrid was characterized by several methods (thermogravimetry, FT-IR spectroscopy and scanning electron microscopy) highlighting the influence of the supramolecular interactions on the composition, therma…

Increasing the nuclearity and spin ground state in a new family of ferromagnetically-coupled {Ni10} disk-like complexes bearing exclusively end-on br…

2018

The synthesis of a new family of ferromagnetically-coupled {Ni10} clusters counterbalanced by various [Ln(NO3)5]2− ions is herein described. The resulting compounds are organic chelate-free and the metal ions are exclusively bridged by end-on azido ligands to stabilize a beautiful disk-like topology reminiscent of the structure of the brucite mineral.

Fracture Toughness and Bridging Law of 3D Woven Composites

2003

ABSTRACT In the paper, the methodology of measuring G 1 c by using DCB specimens in the presence of large-scale bridging is adapted for investigating the delamination in 3D woven composites. The main novelties introduced in the DCB testing concern a) the loading device, b) the specimen geometry, c) the measurement scheme, and d) the determination of G 1 c and the bridging law from experimental data. The geometry-independent material characteristic G 1c as a function of the initial crack opening displacement (ICOD) is introduced. Typical values of the delamination fracture toughness of 3D glass and carbon composites are presented.

Photoluminescence quantum yield exceeding 80% in low dimensional perovskite thin-films via passivation control

2017

Quasi-2D perovskites with the BA : MA molar ratio equal to 3 : 3 show a remarkable PLQY exceeding 80%, thanks to the use of an electron donor as the passivating agent. These films have been applied in LEDs that exhibit high brightness exceeding 1000 cd m−2 and current efficiencies >3 cd A−1.

Effect of operating conditions and feedstock composition on the properties of manganese oxide or quartz charcoal pellets for the use in ferroalloy in…

2020

peer-reviewed The full text of this article will not be available until the embargo expires on the 26/12/2021 This study investigates the effect of heat treatment temperature on the properties of charcoal composite pellets used for the reduction of ferroalloys. The heavy fraction of biooil was used as a binder for the charcoal ore pellet preparation. The effect of heat treatment temperature on the pellet shrinkage was related to the degree of reduction which varied with feedstock and ore composition. The results showed that the size and shape of the charcoal pellets were not affected by the biooil devolatilization. Manganese charcoal pellets showed higher electrical resistance during pyroly…

Effect of Water on the Mechanical Behaviour of Extruded Flat Bread

1997

Abstract The effect of water on the mechanical properties of extruded breads was studied, at room temperature. As the moisture content was increased from 6 to 9% moisture, the resistance to fracture (compression tests) or rupture (tensile tests) was improved. Above this moisture range, plasticisation by water was the dominant phenomenon. The brittle to ductile transition was observed to occur within a moisture content range from 9 to 13·7% (w/w). The influence of water on the crispness of extruded bread, evaluated with sensory evaluation, is also described.

Fracture of a Brittle Membrane

1997

Formation of an unprecedented (CuBr)5 cluster and a zeolite-type 2D-coordination polymer: a surprising halide effect

2013

A unique pentanuclear cluster within a zeolite-type polymer ([Cu5(μ4-Br)(μ3-Br)2(μ2-Br)2](μ2-MeSPr)3)n (1; void space >81%) and a luminescent 1D ([Cu(μ3-I)]4(MeSPr)3)n polymer, 2, are formed when MeSPr reacts with CuBr and CuI.