Search results for "Composites"

Calorimetry: a Valuable Tool for Emerging Smart Nanomaterials

2012

It is well known that calorimetry is a powerful technique to determine the complete energetics (standard free energy, enthalpy and entropy) of interaction processes. We are now assisting to the increment of the use of nano-calorimetry, which appears rather versatile because it can evidence weak interactions quickly and accurately and, furthermore, needs very small amounts of material. Unfortunately, over the years the calorimetry has been applied to restricted fields so that it has been underemployed in studying smart nanomaterials (polypseudorotaxanes, polymeric aggregates, surface functionalized nanoparticles, nanocomposites, etc.) to which a tremendous scientific interest has been recent…

Influence of M23C6 carbides on the heterogeneous strain development in annealed 420 stainless steel

2020

Understanding the local strain enhancement and lattice distortion resulting from different microstructure features in metal alloys is crucial in many engineering processes. The development of heterogeneous strain not only plays an important role in the work hardening of the material but also in other processes such as recrystallization and damage inheritance and fracture. Isolating the contribution of precipitates to the development of heterogeneous strain can be challenging due to the presence of grain boundaries or other microstructure features that might cause ambiguous interpretation. In this work a statistical analysis of local strains measured by electron back scatter diffraction and …

Natural anti-oxidants immobilized onto carbon nanotubes for thermo-oxidation resistant polymer-based nanocomposites

2014

A general diastereoselective synthesis of highly functionalized ferrocenyl ambiphiles enabled on a large scale by electrochemical purification

2017

International audience; A general synthesis of highly functionalized ferrocenes, which include (P,B)- and (N,B)-ambiphiles, has been developed at a multigram scale. Diastereoselective stepwise modification of di-tert-butylated ferrocenes included the unprecedented separation of electroactive species. Bulky alkyl groups on ferrocenes ensure planar chirality of ambiphiles and enforce closer proximity of antagonist Lewis functions.

Retracted Article: Differential detection and quantification of cyclic AMP and other adenosine phosphates in live cells

2017

A new naphthol-based rhodamine derivative (NpRD) has been developed for the selective and differential detection of adenosine 3′,5′-cyclic monophosphate (cAMP) and adenosine phosphates (APs) (ATP, ADP, and AMP) from other nucleotides. The simple detection and quantification of cAMP in human blood cells and in other samples based on the ‘turn on’ fluorescence properties of this chemosensor through colorimetry or fluorometry makes it unique for probable application in high throughput screening.

Self-assembly of an iron(ii)-based M5L6 metallosupramolecular cage

2011

A pentanuclear M(5)L(6) coordination cage is self-assembled in solution from a rigid linear heteroditopic phen-tpy ligand and an iron (II) salt.

Organic chelate-free and azido-rich metal clusters and coordination polymers from the use of Me3SiN3: a new synthetic route to complexes with beautif…

2019

In this Feature Article, we highlight the feasibility of a new, recently developed approach towards the synthesis of high-spin molecules and single-molecule magnets (SMMs). The key to the preparation of such molecular compounds is the organic azide precursor Me3SiN3, which fosters the formation of 3d-metal azido clusters and coordination polymers without requiring the assistance of any organic chelating/bridging group. All the isolated compounds contain metallic cores which are surrounded by end-on bridging N3− groups. Consequently, the reported molecular materials exhibit ferromagnetic exchange interactions between the spin carriers, resulting in the stabilization of the maximum possible s…

Selective precipitation of alkyl dihalides using a newly synthesized water-soluble bisphosphorylpillar[5]arene

2016

Bisphosphorylpillar[5]arenes ( and ) were synthesized and used to study the host-guest complexation in organic solvents and water. The interactions between the guests and the phosphate of the hosts lead to strong binding towards alkyl dihalides and alkyldiammonium ions. may be used to detect or separate alkyl dihalides in water due to the rapid precipitation of the complex.

Single particle jumps and correlated ionic motions in glass-ceramics

1993

Using impedance spectroscopy, the ion transport in poorly Li-conducting aluminosilicate glass ceramics and their precursor glasses has been measured for temperatures 50 K < T < 550 K and covering a frequency range of more than 14 decades from 10 mHz up to 3 THz. In addition to the familiar cooperative ionic motion dominating at high temperatures, for the first time dielectric relaxation due to elementary hopping processes is observed well below room temperature.

Study of morphology, mechanical properties, and thermal degradation of polycarbonate-titania nanocomposites as function of titania crystalline phase …

2013

Titania nanoparticles were prepared using a sol–gel method and calcination at 2008C and 6008C to obtain anatase and rutile phases, respectively. The obtained powders were used to prepare polycarbonate (PC)-titania nanocomposites by melt compounding. The effect of different crystalline phases and amounts of titania, in the range 1–5 wt%, on the morphology, mechanical properties, and thermal degradation kinetics of PC was investigated. The results show that the filler modified the plasticity or rigidity of the polymer and influenced the degradation kinetics, in different ways depending on the type and amount of titania. POLYM. COMPOS.,