Nitric acid leaching of polymetallic middlings of concentration

Investigations into the nitric acid leaching of polymetallic middlings with the purpose of the maximal recovery of copper and zinc into the solution are performed. Using methods of mathematical planning of the experiment, the optimal process parameters are determined: ratio L: S = 5, the consumption of nitric acid is 80 cm3 per 20 g of the charge, and the process duration is 120 min. © 2013 Allerton Press, Inc

Model of Self-Identification of Youth in the Global Communication Environment

Identity is the result of an identification process. The essence of the identification process is expressed in the acceptance of a certain social role by an individual in the process of entering a social group. The psychological meaning of the phenomenon of “identity” reflects the inner identity and integrity of an individual. This phenomenon can affect both an individual and a group. The novelty of the research is determined by the fact that important factors in the process of identity development are specific events in the past and present, periods of crisis and changes in the history of society. It is shown that the main psychological mechanism for the development of identity is identification associated with the interaction between an individual and a social group. The development of personality identity includes a number of types of identity and continues during ontogenesis, is a dynamic and uneven process. The authors show that the concept of national identity within the framework of various fields of psychological science can relate to a group and a person. The practical significance of the study is determined by the fact that in the study the authors understand national identity as the cognitive and emotional awareness of a person of his own belonging to a particular nation, which has its own characteristics. Student (late adolescence) age is decisive in the formation of a person's identity and sensitive for the development of his national identity. The psychological mechanism for the development of a person's national identity at this age is national identification. An insufficient study of the development of the national identity of student youth has been established

Technology for the hydrometallurgical processing of a complex multicomponent sulfide-based raw material

An analysis of the methods currently used for the metallurgical processing of polymetallic middlings from the beneficiation of sulfide ores shows that the oxidant which is the most promising for use as an agent to leach the middlings is nitric acid. A technology is developed to process hard-to-decompose middlings with the use of nitric acid. © 2013 Springer Science+Business Media New York

EXPERIMENTAL ASSESSMENT OF THE EFFICIENCY OF THE TRAMETIN AT EXPERIMENTAL SALMONELLOSIS OF LABORATORY AND AGRICULTURAL ANIMALS

Both clinical observation of animals and data of laboratory researches testify to the fact that veterinary medicine Trametin has high prophylactic efficacy at experimental salmonellosis in mice and in on-the-farm conditions in pigs. At the introduction of the medicine in an optimal dose while modelling dark stress we observed an increase in weight gains. The results of laboratory studies showed an increase in the protein content in blood serum, an increase in the content of phosphorus and calcium, an increase in hemoglobin and red blood cells. Phagocytic activity of piglets' blood in the group that received Trametin increased by 25 % in comparison with control values

Social and medical risks in the professional activity of drivers of the joint stock company “Lorry”

This article reviews the features of the assessment of sociomedical risks in the professional activity of heavy vehicles drivers (based on an example of the joint ctock company “Lorry”).В статье рассмотрены особенности оценки социально-медицинских рисков в профессиональной деятельности водителей большегрузных транспортных средств (на примере Акционерного общества «ЛОРРИ»)

Studies on the regularities of the steelmaking zinc-bearing dusts leaching in ammonium chloride solutions

Dust from steelmaking production, in particular electric arc furnace dust (EAFD), is a rich secondary source of zinc. Different approaches to the EAFDs processing with the production of zinc oxide and metal phases as a final product have been studied. Ammonium chloride leaching is selective for zinc, does not require special acid-resistant equipment, and is relatively cheap. The advantages of this method are the possibility of obtaining metallic zinc as a commercial product and the absence of the need for additional solution purification from iron and chlorine ions. Chemical and mineral characterization of Waelz-oxide after the first stage of calcination are presented, the main identified phase is zinc oxide (ZnO), a small amount of Zn associated with iron (Zn2Fe2O4) in the ferrites form and lead in the oxide phase (PbO) are also determined. The thermodynamic analysis of the Zn(II) – NH4Cl – NH3 – H2O system in the HYDRA software medium was carried out, the main zinc compounds were determined under leaching conditions. A matrix of changing conditions is compiled with using the full three-factor experiment method. Based on the obtained results, in the Statistica-10 program, three-dimensional dependences of zinc extraction on varied parameters were constructed and equations describing these dependencies were obtained. The optimal leaching parameters were determined: the concentration of ammonium chloride 4 mol/dm3, the concentration of ammonia 4 mol/dm3, the ratio L:S = 15. © 2019, "Ore and Metals" Publishing house. All rights reserved