Search results for "Note"

Ab initio modelling of Y-O cluster formation in γ-Fe lattice

2016

Ab initio modelling of Y and O impurity atoms as well as VFe vacancies in the fcc-Fe lattice is performed in order to calculate the interactions between these defects, which are important for understanding of nanoparticles’ formation within the oxide dispersed strengthened steels. Large scale parallel calculations based on plane-wave method realised in VASP computer code show that VFe vacancies considerably influence the binding between the impurity atoms. In this study, we present the results of performed calculations providing the detailed information about the binding energies between the defects, the changes of their effective charges as well as displacements of the substitute atoms rel…

Nanostructuring Biopolymers for Improved Food Quality and Safety

2018

Abstract Food-grade biopolymers, apart from their inherent nutritional properties, can be tailored designed for improving food quality and safety, either serving as delivery vehicles for bioactive molecules, or as novel packaging components, not only improving the transport properties of biobased packaging structures, but also imparting active antibacterial and antiviral properties. In this chapter, the potential of different food-grade biopolymers (mainly proteins and carbohydrates but also some biopolyesters) to serve as encapsulating matrices for the protection of sensitive bioactives or as nanostructured packaging layers to improve transport properties and control the growth of pathogen…

New biomaterials: Biofabrication of biosilica-glass by sponges

2008

Computational strategies for the design of new enzymatic functions

2015

In this contribution, recent developments in the design of biocatalysts are reviewed with particular emphasis in the de novo strategy. Studies based on three different reactions, Kemp elimination, Diels–Alder and Retro-Aldolase, are used to illustrate different success achieved during the last years. Finally, a section is devoted to the particular case of designed metalloenzymes. As a general conclusion, the interplay between new and more sophisticated engineering protocols and computational methods, based on molecular dynamics simulations with Quantum Mechanics/Molecular Mechanics potentials and fully flexible models, seems to constitute the bed rock for present and future successful desig…

New Calibration Model: Combining Integrated Calibration Method and H-point Standard Addition Method to Detect and Avoid Interference Effects

2018

A new calibration methodology based on the combination of integrated calibration method (ICM) and the H-point standard addition method (HPSAM) is presented. It allows the diagnosis and correction o...

ChemInform Abstract: Calixarenes in Self-Assembly Phenomena

2000

New Tools for Characterizing Metallic Nanoparticles: AgNPs, A Case Study.

2015

Currently, transmission electron microscopy (TEM) is the main technique for estimating the sizes of spherical nanoparticles (NPs) and through them, their concentrations. This paper demonstrates for the first time that C18 reversed-phase capillary liquid chromatography (Cap-LC) coupled to diode array detection (DAD) has the potential to estimate mean concentrations of silver nanoparticles (AgNPs) and thereby determine their average size. Direct injection of the sample without previous extraction or separation steps is carried out. Only a unique standard with a known AgNP size is needed for the calibration. In a first approach, the new method has been tested over silver nanoparticles, produce…

ChemInform Abstract: Catenanes and Threaded Systems: From Solution to Surfaces

2009

Functional catenanes and threaded systems able to perform controllable mechanical motions are ideally suited for the design of molecular devices displaying mechanical, electronic, information or sensing functions. These systems have been extensively studied in solution phase and numerous examples of stimuli-driven molecular shuttles have been reported. However, for fully developing their potential applications, they must be interfaced with the macroscopic world. To achieve this objective, in the last few years catenanes and rotaxanes have been organized over surfaces in the form of chemisorbed monolayers or physisorbed monolayers, multilayers and thin films. This tutorial review summarizes …

Alkyloxy modified pyrene fluorophores with tunable photophysical and crystalline properties

2019

Novel alkyloxy modified 2,7-di-tert-butyl-4,5,9,10-tetra(arylethynyl)pyrenes were prepared through a straightforward Sonogashira coupling approach. Optical properties such as quantum yields and absorption/emission spectra of the fluorophores were investigated by UV/Vis and fluorescence measurements. Aggregation induced excimer formation of the chromophores in polar solvents and in the solid state was proved by the presence of a characteristic bathochromically shifted emission band and a decrease of the emission capability. These results strongly indicate the unexpected observation that the excimer formation of adjacent pyrene rings is not prevented by the introduction of bulky tert-butyl su…

Electrocrystallization of Monolayer-Protected Gold Clusters : Opening the Door to Quality, Quantity, and New Structures

2017

Thiolate-protected metal clusters are materials of ever-growing importance in fundamental and applied research. Knowledge of their single-crystal X-ray structures has been instrumental to enable advanced molecular understanding of their intriguing properties. So far, however, a general, reliable, chemically clean approach to prepare single crystals suitable for accurate crystallographic analysis was missing. Here we show that single crystals of thiolate-protected clusters can be grown in large quantity and very high quality by electrocrystallization. This method relies on the fact that charged clusters display a higher solubility in polar solvents than their neutral counterparts. Nucleation…