3 research outputs found

    Дослідження переробки нікель-кобальтвмісних металургійних відходів екологічно безпечним способом водневого відновлення

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    We studied kinetic patterns of hydrogen reduction of the scale of a nickel-cobalt containing precision alloy at a temperature of 673‒1573 K over a period from 0 to 180 minutes. The highest degree of reduction was achieved after thermal treatment at 1273 K – 99 %. This is predetermined by the intensification of reduction processes and a sufficient level of porosity, which ensures satisfactory gas exchange. It was discovered that the starting scale consists mainly of Fe3O4, Fe2O3 and FeO with atoms substituting their alloying elements. The target product of metallization had a sponge-like microstructure and consisted mainly of the solid solution of Co and Ni atoms in γ-Fe and the residual non-reduced Fe3O4 and FeO. The resulting phases had no noticeable susceptibility to sublimation.This has ensured a reduction in the losses of alloying elements while receiving and using the highly-alloyed metallized scale, which was confirmed by experimental- industrial tests. At the same time, recycling of industrial wastes contributes to a reduction in the technogenic intensity of industrial regions and improves ecological safety of the environmentИсследована кинетика водородного восстановления окалины никель-кобальтсодержащего прецизионного сплава. Целевой продукт металлизации после восстановления при 1273 K имел губчатую микроструктуру, преимущественно состоял из твердого раствора атомов Ni и Co в γ–Fe. Также выявлен остаток Fe3O4 и FeO. Опытно-промышленные испытания подтвердили эффективность использования новой легирующей добавки с параллельной утилизацией техногенных отходовДослідженно кінетику водневого відновлення окалини нікель-кобальтвмісного прецизійного сплаву. Цільовий продукт металізації після відновлення при 1273 K мав губчасту мікроструктуру, переважно складався з твердого розчину атомів Ni та Co в γ–Fe. Також виявлено залишок Fe3O4 та FeO. Дослідно-промислові випробування підтвердили ефективність використання нової легуючої добавки з паралельною утилізацією техногенних відході

    Antiproliferative, Apoptotic, and Autophagic Activity of Ranibizumab, Bevacizumab, Pegaptanib, and Aflibercept on Fibroblasts: Implication for Choroidal Neovascularization

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    Purpose. Choroidal neovascularization (CNV) is one of the most common complications of retinal diseases accompanied by elevated secretion of vascular endothelial growth factor (VEGF). Intravitreal anti-VEGFs (ranibizumab, bevacizumab, pegaptanib, and aflibercept) can suppress neovascularization, decrease vascular permeability and CNV size, and, thereby, improve visual function. The antiproliferative, apoptotic, and autophagic effect of anti-VEGF drugs on fibroblasts found in CNVs has not been yet explored. Methods. Concentration-dependent cellular effects of the four anti-VEGFs were examined in L929 fibroblasts over a 5-day period. The cell survival, mitotic and polykaryocytic indices, the level of apoptosis and autophagy, and the cellular growth kinetics were all assessed. Results. The anti-VEGFs could inhibit the survival, mitotic activity, and proliferation as well as increase the cellular heterogeneity, apoptosis, and autophagy of the fibroblasts in a dose-dependent manner. Cellular growth kinetics showed ranibizumab to be less aggressive, but three other anti-VEGFs showed higher antiproliferative and apoptotic activity and expressed negative cellular growth kinetics. Conclusions. The antiproliferative, apoptotic, and autophagic activity of anti-VEGFs upon fibroblasts may explain the cellular response and the etiology of CNV involution in vivo and serve as a good study model for CNV in vitro

    Research Into Recycling of Nickel­cobalt­containing Metallurgical Wastes by the Ecologically­safe Technique of Hydrogen Reduction

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    We studied kinetic patterns of hydrogen reduction of the scale of a nickel-cobalt containing precision alloy at a temperature of 673‒1573 K over a period from 0 to 180 minutes. The highest degree of reduction was achieved after thermal treatment at 1273 K – 99 %. This is predetermined by the intensification of reduction processes and a sufficient level of porosity, which ensures satisfactory gas exchange. It was discovered that the starting scale consists mainly of Fe3O4, Fe2O3 and FeO with atoms substituting their alloying elements. The target product of metallization had a sponge-like microstructure and consisted mainly of the solid solution of Co and Ni atoms in γ-Fe and the residual non-reduced Fe3O4 and FeO. The resulting phases had no noticeable susceptibility to sublimation.This has ensured a reduction in the losses of alloying elements while receiving and using the highly-alloyed metallized scale, which was confirmed by experimental- industrial tests. At the same time, recycling of industrial wastes contributes to a reduction in the technogenic intensity of industrial regions and improves ecological safety of the environmen
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