Search results for "Note"

Alternating current electrogravimetry of copper electrodissolution in a sulfuric acid solution

2017

Abstract Copper electrodissolution processes have been studied by means of electrochemical impedance spectroscopy and ac-electrogravimetry (mass impedance). During ac-electrogravimetry acquisition, mass decreases or increases due to the electrodissolution or the electrodeposition of copper, respectively. As a result, this continuous mass drift makes impossible obtaining a true ac-electrogravimetry response unless a numerical correction was applied. It has been compared the electrochemical behavior of copper layers previously treated and other freshly deposited on the gold electrode of the quartz crystal microbalance. The simultaneous analysis of both impedance functions has allowed separati…

Stamping of monomeric SAMs as a route to structured crystallization templates: patterned titania films.

2000

Gold-coated glass slides have be patterned by using self-assembled monolayers (SAM) of alkane thiols. Through the use of a special thiol terminated with a styrene monomer, microstructures of 5 to 10 microm width and 70 A height have been formed on the surface by graft polymerization of styrene. These patterned gold slides have then been used to template the precipitation of thin titania films from ethanolic solutions of titanium isopropoxide to create microstructured architectures in the film. Plasmon resonance spectra have established the presence of different steps in the process and have been used to follow the kinetics of the precipitation of titania on the surface. The structured TiO2 …

Rhodanine-based dyes absorbing in the entire visible spectrum

2017

A series of new broad-absorbing dyes based on rhodanine derivatives conjugated with triarylamines using Q5 a fluorene backbone was synthesized. Spectroscopic and electrochemical characterizations, along with theoretical calculations at the B3LYP/cc-pVDZ level, revealed interesting properties of the dyes, which make the dyes efficiently absorb in the entire visible spectrum.

Cover Picture: Solid-State Molecular Nanomagnet Inclusion into a Magnetic Metal-Organic Framework: Interplay of the Magnetic Properties (Chem. Eur. J…

2015

First-principles calculations of oxygen interstitials in corundum: a site symmetry approach

2017

The authors are indebted to R. Vila, A. Popov and A. Lushchik for stimulating discussions. This work was carried out within the framework of the EUROfusion Consortium and received funding from the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. Support from Latvian National Research Program IMIS2 (2014–2017) is also appreciated. Calculations were carried out using both the Marconi supercomputer system at the Computational Simulation Centre and the Computer Center of St. Petersburg State University.

Negative thermal expansion of quartz glass at low temperatures: An ab initio simulation study

2017

Abstract Using a mixed classical Molecular dynamics (MD)/ab initio simulation scheme combined with a quasi-harmonic approximation, we calculate the linear thermal expansion coefficient αL(T) in vitreous silica glasses. The systems are first cooled down by classical MD simulations. Then they are structurally relaxed by ab initio DFT calculations. The vibrational properties are calculated employing the frozen phonon method, and these results are finally used to calculate the Helmholtz free energy as a function of volume. In agreement with experiments, our simulations predict that αL(T) is negative at low temperatures up to T ≈ 150 K. In this low-temperature regime, the simulation results are …

MWCNTs-Supported Pd(II) Complexes with High Catalytic Efficiency in Oxygen Reduction Reaction in Alkaline Media

2018

We report here the remarkable catalytic efficiency observed for two Pd(II) azamacrocyclic complexes supported on multiwalled carbon nanotubes (MWCNTs) toward oxygen reduction reactions. Beyond a main (90%) 4e

Self-assembly and rheology of dipolar colloids in simple shear studied using multi-particle collision dynamics.

2017

Magnetic nanoparticles in a colloidal solution self-assemble in various aligned structures, which has a profound influence on the flow behavior. However, the precise role of the microstructure in the development of the rheological response has not been reliably quantified. We investigate the self-assembly of dipolar colloids in simple shear using hybrid molecular dynamics and multi-particle collision dynamics simulations with explicit coarse-grained hydrodynamics, conduct simulated rheometric studies and apply micromechanical models to produce master curves, showing evidence of the universality of the structural behavior governed by the competition between the bonding (dipolar) and erosive …

ChemInform Abstract: Phenylethynyl- and Phenylethenylmetacyclophanes.

2010

The cyclophanes 6,8,10 and 13–15 were synthesized by cesium assisted ring closure reactions. The main interest in these systems concerns the interaction of the unsaturated bridge with the tolan and the stilbene chromophores, respectively.

Multifunctional nanocarriers for biomedical applications

2013

Polymeric vesicles (Pluronic ® L-121) loaded with magnetic nanoparticles (MNP) and an anti-cancer drug (camptothecin) were prepared continuously in a micro mixing device. Characterization by TEM confirmed the successful incorporation of the MNP and DLS measurements showed a relatively narrow size distribution of the hybrid polymersomes. A very high drug loading of camptothecin (100 μg/ml in the polymersome formulation) was reached and a drug release study of loaded magnetic polymersomes has shown a sustained camptothecin release over several days. Carboxylation of Pluronic ® L-121 was performed and enabled a further surface functionalization with bombesin, a 14 amino acid peptide, which bin…