Structure of Zinc Nanotubes

Crystallography Reports - The formation of Zn-based nanotubes by electrochemical synthesis in pores of template polymer matrices is considered. It is established that the number of defects in the...     

Features of Epoxidation of Fatty Acid Methyl Esters in a Bubble Reactor

Russian Journal of Applied Chemistry - The patterns of epoxidation of linoleic acid methyl ester in a mixture of methyl esters of sunflower oil fatty acids with atmospheric oxygen in a bubble...     

Investigation of the influence of electron irradiation on the properties of cobalt nanotubes

Cobalt nanotubes have been synthesized by electrochemical deposition in pores of ion track membranes. The structures obtained have been studied by scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction analysis, and gas permeability method. The influence of electron irradiation on the cobalt nanotube structure has been investigated. It is shown that an increase in the irradiation dose leads to the transformation of the sample crystal structure. This fact can be explained by the simultaneous reduction of the β-Co metastable phase and relaxation of the microstress formed by the fcc phase in the lattice. The degree of sample texturing along the [100] direction increases under electron irradiation. The dependences of the resistive and magnetic properties of cobalt nanotubes on the irradiation dose have been analyzed.     

Study of the Reactivity of Ni Nanotubes in Media with Different рН

Nickel nanotubes have been synthesized by electrochemical deposition, and their reactivity in aggressive media has been investigated. Kinetic curves of the variation in the atomic ratio between Ni and O in the nanotube crystal structure as a function of the medium acidity are built.     

Determination of Optimal Conditions for Electoless Synthesis of Copper Nanotubes in the Polymer Matrix

Russian Journal of General Chemistry - The effects of temperature and the components ratio on the formation of copper nanotubes in tracketched membrane matrix and crystalline structure of the...     

Instability of monovalent ions of transitional metals in alkaline earth fluorides: CaF<Subscript>2</Subscript> and SrF<Subscript>2</Subscript> activated by Co<Superscript>2+</Superscript> or Ni<Superscript>2+</Superscript>

The ground state of monovalent ions of transitional metals in alkaline-earth fluorides is localized in the conduction band. It is shown by the example of monovalent Co and Ni ions in CaF₂ and SrF₂ crystals that this is responsible for the unstable state of these ions in cubic environments. A stable state is achieved by the monovalent ions shifting to off-center positions.     

Evolution of the polyethylene terephthalate track membranes parameters at the etching process

A comprehensive study of parameters of the track membranes based on the polyethylene terephthalate has been carried out at different formation stages. Using the X-ray diffraction analysis, the changes in the structure of the polymer after its irradiation, UV-sensitization and etching are shown. By means of scanning electron microscopy, a sequential analysis of the variation of the parameters of the track membrane during the etching has been carried out, based on which the evolutions of surface morphology and pore sizes are shown.     

Thermal annealing-induced modification of the structure and electrical conductivity of metallic nanotubes embedded in PET track-etched membranes

This work is dedicated to developing a simple methodology that allows for the application of a thermal annealing process, which can improve the conductivity of metallic nanostructures, embedded in porous track-etched membranes based on polyethylene terephthalate (PET TeMs), but at the same time, does not compromise the mechanical properties. Zinc, copper, and cobalt nanotubes (NTs) prepared by electrochemical deposition in PET TeMs were annealed at 200 °C for different time periods. The effects of annealing treatment on the structural and electrical properties were investigated by scanning electron microscopy, X-ray diffraction, and room-temperature resistance measurements. Choosing the appropriate annealing time for Zn or Cu-NTs allows controlling the formation of an oxide phase in these nanostructures. The presence of the oxide phase in an amount of no more than 10–15 wt% led to a decrease in the resistivity and an increase in the conductivity. Thermal annealing of Co-based NTs changed intensities of the metastable fcc β-Co and stable hcp α-Co phases. The metastable β-Co phase caused additional defects due to a change in the crystallite size after 90 min of thermal annealing.     

Structural Characteristics and Ionic Composition of a Colloidal Solution of Silver Nanoparticles Obtained by Electrical-Spark Discharge in Water

Colloid Journal - This work is devoted to studying the structural and morphological properties of a silver colloidal solution obtained by the method of electrical-spark discharge in distilled...