Thermobaric synthesis, structure, and properties of Dy x Cu 3V4O12

The perovskite-like compound Dy x Cu3V 4O12 (x = 0.67-0.75) is synthesized under high pressure (P = 4.0-9.0 GPa) and temperature (T = 1000 C). Its crystal structure is determined (Im-3 space group, Z = 2, a = 7.29348(7) Å) by means of powder X-ray diffraction. The basic lengths and bond angles are defined. It is found that the high-pressure phase of Dy x Cu3V 4O12 is characterized by metallic conductivity and paramagnetic properties. © 2013 Allerton Press, Inc

Microstructure of luminescent MgAl2O4 nanoceramics

Luminescent transparent nanoceramics were obtained by thermobaric treatment (TBT) of magnesium aluminium spinel nanopowder. The morphological features were studied by scanning electron microscopy combined with X-ray powder diffraction. Obtained ceramics do not have any agglomerates and pores larger than 100 nm. Crystallites have a high size uniformity. An increase in the lattice constant of nanoceramics compared to the initial powder is observed. Under the TBT, a decrease in the region of coherent scattering due to elastic deformation of crystallites is found. The absence of cracks, large pores, nanosize grains, and high size uniformity reduce light loss in the material, increasing its transparency. Point defects were characterized by photoluminescence and electron spin resonance (ESR) methods. The glow in the 1.8 eV band is caused by the presence of Ti3+ impurity ions. An abnormally wide peak with a maximum at 2.4 eV in the photoluminescence spectrum is recorded. This signal is a superposition of the Mn2+ ions emission bands and oxygen vacancies (F and F+ centres). In the ESR spectrum, signals from impurity ions of iron, titanium, and manganese, as well as an intense signal at g = 2.005 associated with oxygen vacancies in nanoceramics were detected. © 2018 Institute of Physics Publishing. All rights reserved.The work was done as a part of the government task (№3.1485.2017/4.6) of the Ministry of Education and Science of the Russian Federation and was carried out in accordance with the scientific and research plans and state assignment of the Institute of Solid State Chemistry of the Ural Branch of the Russian Academy of Sciences (AAAA-A16-116122810212-5).et al.;NT-MDT Spectrum Instruments;Ostec-ArtTool Ltd.;Promenergolab LLC;Russian Foundation for Basic Research;Taylor and Francis Grou

THE EFFECT OF THERMOBARIC TREATMENT ON THE MAGNETOCALORIC EFFECT IN ALLOYS BASED ON Ni-Mn-In

In alloys Ni47Mn42In11 and Ni46Mn43In11 the TBT leads to a decrease in ΔS. For Ni45Mn44In11 alloy the ΔS value before and after TBT practically did not change, but its max-imum shifted along the temperature scale from 200 K to 300 K.Работа выполнена в рамках государственного задания МИНОБРНАУКИ России (тема «Спин», № АААА-А18-118020290104-2; тема «Новые функциональные матери-алы для перспективных технологий: синтез, свойства, спектроскопия и компьютерное моделирование», № АААА-А19-119031890025-9) при частичной поддержке РФФИ (проект № 18-02-00739)