Cement-free binders for radioactive waste produced from blast-furnace slag using vortex layer activation technology

The paper addresses the issue of recycling granulated blast-furnace slag (gBFS) as a source for production of cement-free binder materials for further usage in rare-earth metals production for radioactive waste disposal. The use of the vortex layer activator was provided as main technique allowing to produce high-dispersed chemically activated binders. The paper examines the effect of processing conditions on the physical-chemical and mechanical properties of the resulting BFS-based cement-free materials and gBFS-based concretes

Rare earth elements materials production from apatite ores

The paper deals with the study of processing apatite ores with nitric acid and extraction of the rare earth elements. The rare earth elements can be successfully separated and recovered by extraction from the nitrate- phosphate solution, being an tributyl phosphate as extraction agent. The developed scheme of the processing apatite concentrate provides obtaining rare earth concentrates with high qualitative characteristics

Extraction of rare earth elements from hydrate-phosphate precipitates of apatite processing

The features of extraction of rare earth elements (REE) were considered from hydrate-phosphate precipitates of REE of apatite processing by nitric acid technology. The preliminary purification of nitrate solution of REE from impurities of titanium, aluminum, iron, uranium and thorium was suggested to obtain stable solutions not forming precipitates. Washing the extract was recommended with the evaporated reextract that allows to obtain directly on the cascade of REE extraction the concentrated solutions suitable for the separation into groups by the extraction method. Technical decisions were suggested for the separation of REE in groups without the use of salting-out agent

Cement-free binders for radioactive waste produced from blast-furnace slag using vortex layer activation technology

The paper addresses the issue of recycling granulated blast-furnace slag (gBFS) as a source for production of cement-free binder materials for further usage in rare-earth metals production for radioactive waste disposal. The use of the vortex layer activator was provided as main technique allowing to produce high-dispersed chemically activated binders. The paper examines the effect of processing conditions on the physical-chemical and mechanical properties of the resulting BFS-based cement-free materials and gBFS-based concretes

Rare earth elements materials production from apatite ores

The paper deals with the study of processing apatite ores with nitric acid and extraction of the rare earth elements. The rare earth elements can be successfully separated and recovered by extraction from the nitrate- phosphate solution, being an tributyl phosphate as extraction agent. The developed scheme of the processing apatite concentrate provides obtaining rare earth concentrates with high qualitative characteristics

Extraction of rare earth elements from hydrate-phosphate precipitates of apatite processing

The features of extraction of rare earth elements (REE) were considered from hydrate-phosphate precipitates of REE of apatite processing by nitric acid technology. The preliminary purification of nitrate solution of REE from impurities of titanium, aluminum, iron, uranium and thorium was suggested to obtain stable solutions not forming precipitates. Washing the extract was recommended with the evaporated reextract that allows to obtain directly on the cascade of REE extraction the concentrated solutions suitable for the separation into groups by the extraction method. Technical decisions were suggested for the separation of REE in groups without the use of salting-out agent

Influence of the Dielectric Matrix on the Electrical Nanocomposites Based on Oxidized Multi-Walled Carbon Nanotubes

В данной работе рассмотрено влияние окислительных обработок на свойства многослойных углеродных нанотрубок (МУНТ). Рассмотрены экспериментальные температурные зависимости электропроводности (в диапазоне температур 4,2-293 К) и полевые зависимости магнетосопротивления (в полях до 9 Тл при температуре 10 К) образцов МУНТ с модифицированными окислением поверхностными слоями, а также композитов на их основе. Установлено, что окисление поверхностных слоев МУНТ в растворах кислот ведет к изменению температурных зависимостей электропроводности. Введение МУНТ в диэлектрическую матрицу полиметилметакрилата (ПММА) приводит к температурной зависимости проводимости, близкой к типичной для прыжковой проводимости с переменной длиной прыжка для трехмерного случая.In this paper we consider the effect of oxidative treatments on the properties of multiwalled carbon nan- otubes (MWNT). The experimental temperature dependence of electrical conductivity (in the temperature range 4,2-293 K) and field dependence of magnetoresistance (in fields up to 9 Tl at 10 K) of the samples with MWCNT modified by oxidation of the surface layers, as well as the composites based on them. It was established that the oxidation of the surface layers of MWCNTs in acid solutions leads to a change in the temperature dependence of electrical conductivity. Introduction of MWCNTs in a dielectric matrix of polymethylmethacrylate (PMMA) leads to the dependence of the conductivity close to that typical for hopping conductivity with variable hopping length, three-dimensional case

Influence of the Dielectric Matrix on the Electrical Nanocomposites Based on Oxidized Multi-Walled Carbon Nanotubes

В данной работе рассмотрено влияние окислительных обработок на свойства многослойных углеродных нанотрубок (МУНТ). Рассмотрены экспериментальные температурные зависимости электропроводности (в диапазоне температур 4,2-293 К) и полевые зависимости магнетосопротивления (в полях до 9 Тл при температуре 10 К) образцов МУНТ с модифицированными окислением поверхностными слоями, а также композитов на их основе. Установлено, что окисление поверхностных слоев МУНТ в растворах кислот ведет к изменению температурных зависимостей электропроводности. Введение МУНТ в диэлектрическую матрицу полиметилметакрилата (ПММА) приводит к температурной зависимости проводимости, близкой к типичной для прыжковой проводимости с переменной длиной прыжка для трехмерного случая.In this paper we consider the effect of oxidative treatments on the properties of multiwalled carbon nan- otubes (MWNT). The experimental temperature dependence of electrical conductivity (in the temperature range 4,2-293 K) and field dependence of magnetoresistance (in fields up to 9 Tl at 10 K) of the samples with MWCNT modified by oxidation of the surface layers, as well as the composites based on them. It was established that the oxidation of the surface layers of MWCNTs in acid solutions leads to a change in the temperature dependence of electrical conductivity. Introduction of MWCNTs in a dielectric matrix of polymethylmethacrylate (PMMA) leads to the dependence of the conductivity close to that typical for hopping conductivity with variable hopping length, three-dimensional case