Polychelates Based on Magnesium, Aluminum, Iron, Zirconium, and Vanadyl Acetylacetonates - Synthesis, Structure and Properties

The formation of polymeric acetylacetonates of magnesium, aluminum, iron, zirconium, and vanadyl under conditions of mechanochemical activation with subsequent condensation in boiling toluene has been investigated. The obtained compounds have been studied by the methods of gel chromatography, X-ray diffractometry, and positron annihilation and IR spectroscopy. Aluminum chelates have been studied by means of NMR spectroscopy. It has been demonstrated that the mechanochemical activation with subsequent boiling in toluene results in the formation of polymeric chelates, mostly those of iron, zirconium and, to a smaller degree, chelates of aluminum, magnesium, and vanadyl. The molecular weight of soluble high-molecular fractions is in the range 3000–5000 Da. The layered polymer structure has been revealed. Cross-section areas of polymer chains and volumes of coherent scattering regions have been calculated from the diffractometry data. The morphology of polymers consisting of spherical particles of sizes in the range 100–700 nm has been investigated. Based on the data of positron annihilation spectroscopy (PAS), density, and nitrogen low-temperature adsorption, the dependence of the chelate stability on the specific polarizing potential has been determined. A fractal structure of solid-state polychelates has been revealed.

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X-ray photoelectron spectroscopy and positron annihilation spectroscopy analysis of surfactant affected FePt spintronic films

Applied Surface Science ◽

10.1016/j.apsusc.2014.04.190 ◽

2014 ◽

Vol 308 ◽

pp. 408-413 ◽

Cited By ~ 1

Author(s):

Chun Feng ◽

Xujing Li ◽

Fen Liu ◽

Qiang Wang ◽

Meiyin Yang ◽

...

Keyword(s):

Positron Annihilation ◽

Photoelectron Spectroscopy ◽

Positron Annihilation Spectroscopy ◽

Spectroscopy Analysis ◽

X Ray

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On the Behavior of Yttria/Yttrium during Mechanical Alloying of a Fe - Y2O3 Model Alloy System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.922.598 ◽

2014 ◽

Vol 922 ◽

pp. 598-603

Author(s):

Gerald Ressel ◽

Peter Parz ◽

Alexander Fian ◽

David Holec ◽

Sophie Primig ◽

...

Keyword(s):

Mechanical Alloying ◽

Positron Annihilation ◽

Photoelectron Spectroscopy ◽

Atom Probe Tomography ◽

Elevated Temperatures ◽

Positron Annihilation Spectroscopy ◽

Atom Probe ◽

Model Alloy ◽

High Temperature Strength ◽

X Ray

Mechanical alloying (MA) is an established way to prepare nanocrystalline materials and metastable solutions of materials, which normally have no mutual solubility. This is also the case for oxide dispersion strengthened (ODS) steels with improved mechanical properties at elevated temperatures. It is known that a small addition of yttria (Y2O3) has a beneficial effect on high temperature strength and reduces the creep rate in mechanically alloyed ferritic steels by about six orders of magnitude. In this work we present an experimental study using atom probe tomography, X-ray photoelectron spectroscopy, and positron annihilation spectroscopy combined with first principles modeling focusing on the distribution and behavior of yttria in pure iron prepared by mechanical alloying. Atom probe tomography and X-ray photoelectron spectroscopy measurements as well as positron annihilation spectroscopy conducted on powder particles directly after milling have revealed that a predominantly fraction of the yttria powder dissolves in the iron matrix and Y atoms occupy convenient positions, such as vacancies or dislocations. This is supported by ab initio calculations demonstrating that the formation energy for Y substitutional defects in bcc-Fe is significantly lower in the close neighborhood of vacancies.

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Defects in hard coatings studied by positron annihilation spectroscopy and x‐ray diffraction

Journal of Vacuum Science & Technology A Vacuum Surfaces and Films ◽

10.1116/1.578136 ◽

1992 ◽

Vol 10 (1) ◽

pp. 193-207 ◽

Cited By ~ 31

Author(s):

James P. Schaffer ◽

Anthony J. Perry ◽

Jean Brunner

Keyword(s):

Positron Annihilation ◽

Positron Annihilation Spectroscopy ◽

Hard Coatings ◽

X Ray Diffraction ◽

X Ray

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Post irradiated microstructural characterization of Zr–1Nb alloy by X-ray diffraction technique and positron annihilation spectroscopy

Bulletin of Materials Science ◽

10.1007/s12034-011-0120-6 ◽

2011 ◽

Vol 34 (3) ◽

pp. 507-513 ◽

Cited By ~ 19

Author(s):

P S CHOWDHURY ◽

P MUKHERJEE ◽

N GAYATHRI ◽

M BHATTACHARYA ◽

A CHATTERJEE ◽

...

Keyword(s):

Positron Annihilation ◽

Microstructural Characterization ◽

Positron Annihilation Spectroscopy ◽

X Ray Diffraction ◽

X Ray

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Investigation Of Helium Implanted Fe–Cr Alloys By Means Of X–Ray Diffraction And Positron Annihilation Spectroscopy

Journal of Electrical Engineering ◽

10.2478/jee-2015-0055 ◽

2015 ◽

Vol 66 (6) ◽

pp. 334-338

Author(s):

Patrik Novák ◽

Aleksandr Gokhman ◽

Edmund Dobročka ◽

Jozef Bokor ◽

Stanislav Pecko

Keyword(s):

Positron Annihilation ◽

Domain Size ◽

Surface Region ◽

Grazing Incidence ◽

Positron Annihilation Spectroscopy ◽

Lattice Parameter ◽

Implantation Dose ◽

X Ray Diffraction ◽

Coherent Domain Size ◽

X Ray

Abstract X-ray diffraction (XRD) and positron annihilation spectroscopy (PAS) have been used for the characterization of the two binary alloys Fe-Cr with Cr content 2.36 and 8.39 wt%. The influence of ion implantation on these alloys was studied. Different implantation doses of helium, up to 0.5 C/cm2, were used to simulate neutron-induced damage in a sub-surface region. To characterize the damage, a lattice parameter, coherent domain size, residual stress and a crystallographic texture have been studied by grazing incidence X-ray diffraction (GIXRD). It was found out that these parameters showed a similar dependence on the implantation dose as the positron lifetime determined by positron annihilation spectroscopy.

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Crystallization phenomena in β-Ga2O3 investigated by positron annihilation spectroscopy and X-ray diffraction analysis

Materials Science and Engineering B ◽

10.1016/s0921-5107(01)01069-8 ◽

2002 ◽

Vol 91-92 ◽

pp. 541-544 ◽

Cited By ~ 6

Author(s):

Wei-Yuan Ting ◽

Adrian H. Kitai ◽

Peter Mascher

Keyword(s):

Diffraction Analysis ◽

Positron Annihilation ◽

Positron Annihilation Spectroscopy ◽

X Ray Diffraction ◽

X Ray

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High-spatial-resolution x-ray microanalysis: Comparison of experiment and incoherent scattering calculations

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148782 ◽

1993 ◽

Vol 51 ◽

pp. 590-591

Author(s):

J. R. Michael ◽

A. D. Romig

Keyword(s):

Electron Beam ◽

Spatial Resolution ◽

Thin Foil ◽

Coherent Scattering ◽

Incoherent Scattering ◽

Spherical Particles ◽

X Ray ◽

Thin Foils ◽

Oriented Parallel ◽

Beam Broadening

There have been many experimental efforts to measure the spatial resolution for x-ray microanalysis in the analytical electron microscope (AEM). There have been three commonly utilized specimen geometries in these experiments: 1) segregant at a grain boundary, 2) interphase boundaries oriented parallel to the electron beam, and most recently 3) spherical particles embedded at various depths in thin foils. The results of many of these experiments have been analyzed with a number of models for the broadening of the electron beam as it traverses the thin foil. These models are typically based on incoherent electron scattering, typical of Monte Carlo simulations. A vast majority of the published spatial resolution data support the incoherent scattering models as the best simulation of spatial resolution for x-ray microanalysis in the AEM. Recent experimental work using embedded particles to measure beam broadening has been used to support the coherent scattering model of beam broadening.

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