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2022 ◽  
Vol 962 (1) ◽  
pp. 012055
Author(s):  
G B Melentiev ◽  
G A Yurgenson ◽  
L M Delitzyn

Abstract The prospects of lithium as a component of new energy are considered. Provides data on the resources of lithium mineral raw materials. Variants of the reconstruction of lithium production facilities in Russia from domestic raw materials are evaluated in order to solve the problem of import substitution. Attention is focused on the choice of objects of priority industrial development and the need to create modern technologies for processing lithium raw materials. It is shown that the restored Zabaikalsk mining and processing plant can be a reliable source of lithium when using new technological solutions for extracting lithium and associated useful components from primary ores and waste of spodumene ores.


2021 ◽  
Vol 937 (4) ◽  
pp. 042013
Author(s):  
N A Ivanova

Abstract The relevance of the study is determined by the fact that the modern ecological situation necessitates the transition of the branches of the national economy from technogenic to sustainable and ecologically balanced development. These processes will be facilitated by the greening of the economy through the modernization of processing industries through the introduction of innovative technological processes that will increase the depth and complexity of processing, which will increase the resource efficiency of the use of hydrocarbons, as well as reduce environmental risks. In the context of an increasing shortage of non-renewable resources, aggravation of environmental problems, introduction of resource-saving and resource-efficient innovative “green” technologies aimed at producing new types of “green” products is a prerequisite for the successful development of the economy and preserving the environment. The novelty of the study is due to the achievement of the “decoupling” effect, which implies an increase in the resource efficiency of the use of raw materials while reducing environmental risks. This implies the creation of such conditions under which, based on the modernization of the economy through innovative technologies that allow meeting the growing needs, the minimization of the use of hydrocarbon resources will be ensured. The most important direction of Russia’s transition to “green development” is to increase the complexity of the use of raw materials, increase the depth of processing, Nelson’s complexity coefficient economically justified extraction of all useful components contained in raw materials and production wastes extracted from hydrocarbon raw materials. The main factor in reducing the burden on the environment, reducing resource intensity is innovative transformations based on the comprehensive use of environmentally friendly low-waste technologies.


Antioxidants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1884
Author(s):  
Sabrina De Brasi-Velasco ◽  
Omar López-Vidal ◽  
María Carmen Martí ◽  
Ana Ortiz-Espín ◽  
Francisca Sevilla ◽  
...  

Autophagy is an essential process for the degradation of non-useful components, although the mechanism involved in its regulation is less known in plants than in animal systems. Redox regulation of autophagy components is emerging as a possible key mechanism with thioredoxins (TRXs) proposed as involved candidates. In this work, using overexpressing PsTRXo1 tobacco cells (OEX), which present higher viability than non-overexpressing cells after H2O2 treatment, we examine the functional interaction of autophagy and PsTRXo1 in a collaborative response. OEX cells present higher gene expression of the ATG (Autophagy related) marker ATG4 and higher protein content of ATG4, ATG8, and lipidated ATG8 as well as higher ATG4 activity than control cells, supporting the involvement of autophagy in their response to H2O2. In this oxidative situation, autophagy occurs in OEX cells as is evident from an accumulation of autolysosomes and ATG8 immunolocalization when the E-64d autophagy inhibitor is used. Interestingly, cell viability decreases in the presence of the inhibitor, pointing to autophagy as being involved in cell survival. The in vitro interaction of ATG4 and PsTRXo1 proteins is confirmed by dot-blot and co-immunoprecipitation assays as well as the redox regulation of ATG4 activity by PsTRXo1. These findings extend the role of TRXs in mediating the redox regulation of the autophagy process in plant cells.


Plants ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2458
Author(s):  
Kseniya Bushmeleva ◽  
Alexandra Vyshtakalyuk ◽  
Dmitriy Terenzhev ◽  
Timur Belov ◽  
Andrey Parfenov ◽  
...  

Researchers are attracted to the wide-ranging, useful components in Aronia melanocarpa berries. They are searching for the most effective ways to extract the active substances that can enhance the body’s protective properties. The current study presents detailed information about the extracts from A. melanocarpa fruits frozen and dried under mild conditions and their chemical composition. In Wistar rats with induced immunosuppression, the effect of chokeberry fruit extracts on the leukocyte formula, phagocytic activity, and cytokine system was studied. It was shown that the A. melanocarpa frozen fruit extract contains more anthocyanins, sugars, and ascorbic acid, and has a more pronounced antioxidant activity determined by the ability to bind APPH-radicals. Moreover, the extract showed membrane-protective and cytoprotective properties against RPMI-1788 cell line. The extract from dried raw material shows a higher antioxidant activity due to the ability to bind DPPH-radicals. It was revealed that extracts from A. melanocarpa fruits promote rapid immune system recovery in rats, normalize the leukocyte count, and improve monocyte and neutrophil phagocytic indicators. Research on the cytokine profile revealed that the anti-inflammatory properties in A. melanocarpa extracts were more pronounced in dried extracts. For several cytokines, a normalization of quantity was noted.


Materials ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 6754
Author(s):  
Gintare Krucaite ◽  
Saulius Grigalevicius

Organic light emitting diode (OLED) is a new, promising technology in the field of lighting and display applications due to the advantages offered by its organic electroactive derivatives over inorganic materials. OLEDs have prompted a great deal of investigations within academia as well as in industry because of their potential applications. The electroactive layers of OLEDs can be fabricated from low molecular weight derivatives by vapor deposition or from polymers by spin coating from their solution. Among the low-molar-mass compounds under investigation in this field, carbazole-based materials have been studied at length for their useful chemical and electronic characteristics. The carbazole is an electron-rich heterocyclic compound, whose structure can be easily modified by rather simple reactions in order to obtain 2,7(3,6)-diaryl(arylamino)-substituted carbazoles. The substituted derivatives are widely used for the formation of OLEDs due to their good charge carrier injection and transfer characteristics, electroluminescence, thermally activated delayed fluorescence, improved thermal and morphological stability as well as their thin film forming characteristics. On the other hand, relatively high triplet energies of some substituted carbazole-based compounds make them useful components as host materials even for wide bandgap triplet emitters. The present review focuses on 2,7(3,6)-diaryl(arylamino)-substituted carbazoles, which were described in the last decade and were applied as charge-transporting layers, fluorescent and phosphorescent emitters as well as host materials for OLED devices.


Author(s):  
V. A. Stepanov

Background. The Witwatersrand gold province located in South Africa is the richest in the world. The Witwatersrand deposits are composite, where osmirids and diamonds are mined along with gold, silver and uranium. The genesis of the Witwatersrand deposits is controversial. Most local geologists support the hypothesis of the presence of paleoplacer deposits with subsequent metamorphic transformation of ore-bearing conglomerates. In addition, there are aeolian, hydrothermal-sedimentary, hydrothermal-sedimentary-metamorphic and magmatic models of ore formation.Aim. To establish the genesis of the Witwatersrand deposits.Materials and methods. Analysis of published literature and factual data.Results. Osmirids and diamonds are mined along with gold, silver and uranium from the composite Witwatersrand deposits. Such a set of useful components is not known in any of the deposits of magmatic or hydrothermal genesis. Considering the confinement of useful components to conglomerates, the detrital nature of most of the gold grains and the presence of various accompanying minerals in the heavy fraction, characteristic of igneous rocks of felsic, basic and ultrabasic composition, the hypothesis of the primary alluvial nature of the deposits of the Witwatersrand province looks the most reasonable.Conclusions. The factual material indicates an alluvial origin of the Witwatersrand deposits with subsequent metamorphic transformation of ore-bearing reefs. The primary alluvial formation of ore-bearing conglomerates is indicated by the confinement of gold and uranium to channel facies with a tendency to accumulate in the basal horizons of the reefs, the presence of rounded gold particles bearing the traces of transportation in alluvial flows, as well as a set of minerals in the heavy fraction of concentrate, characteristic of placers.


2021 ◽  
Vol 22 (2) ◽  
pp. 225-233
Author(s):  
Andrey A. Rasskazov ◽  
Evgeniy S. Gorbatov ◽  
Alexander E. Kotelnikov

The conditions of the formation of nonmetallic and ore minerals in limnogenic structures are considered. It has been established that lakes are natural enriches of a wide range of useful components - silicate, carbonate, water-soluble, ore, organomineral. The most significant minerals of modern lakes, in addition to water, are: sapropel, diatomite, lime and mineral salts. Deposits of sand, clay, oil shale, oil and gas, coal, phosphorites, zeolites, evaporites, bauxites, ferromanganese, copper ores, placer minerals, and some rare and dispersed elements are associated with limnogenic complexes of different ages. It is shown that a greater variety of minerals of ancient lacustrine complexes compared to modern ones is associated both with variations of lacustrine lithogenesis in the past and with post-sedimentation transformations of sedimentary matter. In particular, epigenetic enrichment of ancient lacustrine complexes with ore components is noted. It was revealed that hydrocarbons and diatomites of lacustrine genesis are of a higher quality compared to similar minerals of marine genesis. It is noted that evolutionary changes in the processes of accumulation of limnogenic minerals have affected to the greatest degree biogenic and chemogenic components. An example of this is the progressive accumulation of caustobiolites and the sulfate evolution of evaporites in lacustrine structures during the Phanerozoic. An analysis of the genetic characteristics of lacustrine minerals makes it possible to develop new exploratory traits of a number of sedimentary deposits.


Author(s):  
V. V. Shevchuk ◽  
T. N. Potkina ◽  
O. V. Smetanina

Due to the fact that polyhalite ores are poorly soluble in water, it was of interest to study the method of their processing using acids. The influence of polyhalite size, the hydrochloric acid concentration and consumption, the ratio of L: S, the temperature and time of mixing the pulp on the useful components extraction into the solution have been studied. The optimal conditions for the decomposition of polyhalite with hydrochloric acid have been determined. The degree of useful components extraction into the solution depends on the concentration of hydrochloric acid or on the L:S ratio of the pulp, but in all cases the decomposition of polyhalite occurs without secondary crystal formation, as evidenced by the same degree of potassium and magnesium ions extraction. The degree of potassium and magnesium ions extraction from polyhalite into solution increases with decomposition process temperature, an increase in the consumption of acid and the duration of the reagents interaction, and decreases with increasing acid concentration. The CaSO4 content in the solution increases sharply with an increase in the HCl concentration and is practically independent of the process temperature. Hydrochloric acid extract can be used for phosphate raw decomposition in order to obtain complex fertilizers.


2021 ◽  
Vol 13 (4) ◽  
Author(s):  
Moussa Koulibaly ◽  
Tatiana Chekushina ◽  
Alexey Yankevskiy

The article discusses the issues of increasing the efficiency of extraction of gold-bearing ores from poor ores using gravity using combined geotechnologies at the Sigiri mine (Republic of Guinea). Gravity Recoverable Gold (GRG) is defined as gold present in a particle in sufficient quantities to be selectively recovered from waste rock by gravity methods. Since Guinea is one of the ten leaders among the countries of the African continent in terms of gold reserves (2019 — 700,000 tons), it should be taken into account that the complex of measures for ore processing includes crushing modules interconnected during the technological process, grinding-gravity module, flotation module and metallurgical a module that affects the solution of the problem of integrated development of subsoil in the generally accepted understanding and this is the maximum extraction of recorded reserves from the subsoil and useful components from mined ore. The author presents the influence of the centrifugal concentrator Nelson (Knelson) on increasing the degree of gold recovery from gold-bearing poor ores under high climatic conditions. Increase in gold production by the GRG test method due to the destruction of the ore structure and a significant decrease in density, as well as an increase in the opening of minerals using gravity up to 63 %. Thus, the optimization is classified as medium-coarse gold.


Author(s):  
I.A. Melnichenko ◽  
Yu.V. Kirichenko

Contemporary mining industry is a complex system that is constantly expanding both in terms of explored sources of mineral raw materials and in terms of developing new approaches to mining and processing of minerals. Such a buildup in the scope of tasks set for the industry, as well as the technical progress, lead to various issues related to the quality, quantity and rational use of mineral raw materials. Rationalization, in its turn, should be carried out in a phased manner through the use of comprehensive measures, one of which is reclamation of man-made wastes, represented by waste rocks, tailings, slags, dust, etc. In addition, this approach simultaneously resolves several other important challenges the industry is facing, e.g. increasing the environmental safety of mining regions and increasing the economic feasibility of production by extracting additional components from waste materials. The scope of application of such a solution to the challenge of rationalizing production is immense and can be implemented at many deposits located in the territory of the CIS due to the presence of huge volumes of waste generated by mining raw materials. These wastes were accumulated because of the absence of full-fledged technologies to extract useful components from the rock mass in the past as well as other requirements to ore conditioning than those acting today. For example, in the Republic of Bashkortostan, the overburden dumps and off-balance ores that have been created by mining enterprises amount to more than 1 billion tons, hydraulic-mine dumps of processing plants reach 50 million tons, manmade waters exceed 9 million m3 annually. At the same time, the amount of useful components contained in these man-made deposits can be up to 1.5 million tons for copper, 2 million tons for zinc, about 100 tons of gold as well as significant amounts of other associated components, including various non-metallic formations.


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