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11.
Physicochemical characteristics of carbon nanotubes synthesized on Co2O3 and oxide Cu–Co–Fe catalysts on their base applied in the CO oxidation reaction have been investigated. It is shown that the deposition technology of the active mass, which, according to the X-ray phase analysis, is a mixture of the Cu2(OH)3NO3 and CuO phases, strongly influences the activity of the Cu–Co–Fe/CNT catalysts. The greatest amount of the Cu2(OH)3NO3 phase is observed in the catalysts produced by a single deposition of the active component on carbon nanotubes, which according to the thermodesorption mass spectroscopy, contributes to the formation of active centers with the lower activation energy of the CO2 desorption and the reaction of the CO oxidation proceeds at a considerably lower temperatures. The TEMdata indicate that at the step-by-step deposition of the active mass in the surface layer the formation of the massive agglomerates, which are inhomogeneously located on the disordered structures of nanotubes, and this unfavourably affects the catalytic properties of Cu–Co–Fe/CNT catalysts.  相似文献   
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The influence of temperature on speciation of actinides (Pu, Am) and some fission products (Cs, Sr), sorbed from simulated groundwater onto rocks from the Nizhnekansky massif (gneiss, dolerite) under anaerobic conditions at 20 and 90°С, was studied by sequential extraction. An increase in the contact temperature leads to an increase in the radionuclide uptake percentage and, in some cases, in the content of tightly fixed forms. The radionuclide species undergo redistribution with time.  相似文献   
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Oil and gas facilities—reservoirs, gas pipelines, oil pipelines—belong to industrial facilities of high risk. Uncontrolled development of accident scenarios at oil and gas facilities associated with explosions and fire may lead to significant damages and human casualties. This article presents possible scenarios of occurrence, development, and probability of realization of accidents at oil and gas facilities operated in extreme natural and climatic conditions of the North. Measures aimed at reducing the hazards are suggested.  相似文献   
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Palsa peatlands occupy extensive areas in Western Siberia which is one of the most paludified flat lowlands of the world. Climatic changes in Western Siberia are more dramatic compared with other northern regions, and changes in palsa landscapes are more notable due to the severe continental climate here. The distribution, peculiarities and climate-indication capacities of West Siberian palsas are poorly known outside Russia. Thus, Western Siberia is one of the most interesting vast natural polygons for studying climate-driven changes in the landscapes. This paper aims to fill the gap in knowledge on West Siberian palsas and their capacity as a climate regulator. We present issues in distribution, typology and cyclic development of palsa peatlands and their actual climate-driven changes. We also analyse the role of palsas in the atmospheric cycle of CO2, and the hydrology of the palsa regions.  相似文献   
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Proton‐conducting gel electrolytes based on poly(methyl methacrylate) (PMMA), poly(vinylidene fluoride) (PVdF), and mixtures of PMMA with PVdF or poly(vinyl chloride) doped by acid solutions in aprotic solvents were synthesized and are discussed in this article. The gel conductivity as a function of the concentrations of acid and polymer and the polymeric matrix composition has been analyzed. Extreme dependence of the conductivity on acid and polymer concentrations was found. It was revealed that within the acid concentration range studied, the gel conductivity was higher than the conductivity of the corresponding liquid electrolytes used for the synthesis. The increase in the electrical conductivity with the growth of the systems viscosity is discussed as an indication of a certain involvement of the polymer matrix in the increase of the charge carrier mobility within the frame of a Grotthuss mechanism. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40674.  相似文献   
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Thyroid cancer (TC) is the most common type of endocrine malignancy. Tumour formation, progression, and metastasis greatly depend on the efficacy of mitochondria—primarily, the regulation of mitochondria-mediated apoptosis, Ca2+ homeostasis, dynamics, energy production, and associated reactive oxygen species generation. Recent studies have successfully confirmed the mitochondrial aetiology of thyroid carcinogenesis. In this review, we focus on the recent progress in understanding the molecular mechanisms of thyroid cancer relating to altered mitochondrial metabolism. We also discuss the repurposing of known drugs and the induction of mitochondria-mediated apoptosis as a new trend in the development of anti-TC therapy.  相似文献   
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