Geological-hydrogeochemical characteristics of a "silver spring" water source (the Lozovy ridge)

Geological and hydrogeological characteristics of the Lozovy ridge (Southern Primorye) are studied, as far as karst phenomena are widely distributed within its boundaries. Water-bearing rocks of the karst water source "Silver Spring" ("Serebryany Klyuch"), which is located near the bottom of the "Bear's fang" ("Medvezhiy klyk") cave, are investigated. It is found that karst rocks are presented by calcite (CaCO[3]), and an accessory mineral is barite (BaSO[4]). It is determined that among the trace elements forming the composition of carbonate water-bearing rocks the maximum concentrations are typical for Sr, Ba, Fe, Al, Za, Mn, Cu, and Ni. Also, the chemical composition of the waters taken from the "Silver Spring" water source is studied. These waters are fresh, hydrocarbonate, calcium, and weakly alkaline. Among the elements of the spring, such elements as Sr, Ba, Fe, Al, Zn, Mn, Cu, and Ni have the maximum concentration. The other elements have concentrations less than 1 [mu]g/l

Specific Features of Thermal Systems of Induration Machines for Pellet Production from Iron-ore Concentrates of Different Types

Pellets are one of the main types of iron-ore raw materials used in ferrous metallurgy. In Russia, the overall production of this iron-ore raw material is continuously growing. The analysis of pelletizing technologies over the last years has shown changes in requirements for product quality, process performance, heat and power parameters, environmental performance and production conditions of both fired and pre-reduced pellets. The article provides the analysis of technological and structural defects of conveyor-type induration machines. In order to remove these defects, we have developed an integrated technology for the production of fired pellets of various purposes. This technology made it possible to create an energy-efficient thermal system of the induration machine that has no counterparts in the world. This thermal system takes into account characteristics of the initial raw material. Its implementation at Mikhailovsky GOK in Russia provided a specific natural gas consumption within 8–9 nm3 /t of pellets and specific energy consumption less than 36 kW·h/t of pellets. These parameters were received by mathematical modelling and introduction of two-layer drying in the pellet induration process. The new induration technology has been implemented in Brazil and is now spreading at other plants in Russia. Keywords: pellets, iron-ore concentrates, induration machines, thermal systems, two-layer charging, pellet dryin

Stagnation and renewable growth of enterprises: an empirical analysis by sectors of the Russian economy

An unfavorable external environment requires an emphasis shift in economic researches of enterprise development from factors and mechanisms of growth to the analysis of stagnation processes and the search for mechanisms to enter the path of growth after stagnation. The purpose of this work is to study the intensity of the processes of stagnation and subsequent renewable growth of enterprises in the context of a wide range of sectors of the Russian economy. Signs of stagnation or drop in sales are revealed for 2013–2017, renewable growth – within 4 years after the stagnation period. The research methods are the calculation of economic coefficients and the identification of differences between them using methods of mathematical statistics. It was found that in an unfavorable external environment, significant proportion of Russian enterprises showed signs of stagnation or drop in sales. Certain advantages are shown by high-tech industries, in which the intensity of business stagnation was lower. The most acute period of the crisis was the period 2013–2016. In 2017, there was an adaptation of business to unfavorable environmental conditions, and the share of stagnating enterprises decreased significantly. Calculations showed that the share of enterprises demonstrating long-term renewable growth was at a low level. It reduces their attractiveness to private investors. The “age” factor can be recommended as a significant criterion for investors when choosing firms for financing: young enterprises are less susceptible to stagnation and more likely to enter the path of growth after stagnation

Analysis of Odontology performance of crowns of teeth parodontitis with varying degrees of severity

The results of morphometric parameters in dental patients with parodontitis of varying severity. The relationships between quantity of crowns of teeth and the severity of parodontitis.Представлены результаты морфометрических показателей зубов пациентов с пародонтитом различной степени тяжести. Выявлены связи между величиной коронок зубов и тяжестью течения пародонтита

Measurement of the e+e−→K+K−π+π−e^+e^- \to K^+K^-\pi^+\pi^- cross section with the CMD-3 detector at the VEPP-2000 collider

The process $e^+e^- \to K^+K^-\pi^+\pi^-$ has been studied in the center-of-mass energy range from 1500 to 2000\,MeV using a data sample of 23 pb$^{-1}$ collected with the CMD-3 detector at the VEPP-2000 $e^+e^-$ collider. Using about 24000 selected events, the $e^+e^- \to K^+K^-\pi^+\pi^-$ cross section has been measured with a systematic uncertainty decreasing from 11.7\% at 1500-1600\,MeV to 6.1\% above 1800\,MeV. A preliminary study of $K^+K^-\pi^+\pi^-$ production dynamics has been performed

Study of the process e+e−→ppˉe^+e^-\to p\bar{p} in the c.m. energy range from threshold to 2 GeV with the CMD-3 detector

Using a data sample of 6.8 pb$^{-1}$ collected with the CMD-3 detector at the VEPP-2000 $e^+e^-$ collider we select about 2700 events of the $e^+e^- \to p\bar{p}$ process and measure its cross section at 12 energy ponts with about 6\% systematic uncertainty. From the angular distribution of produced nucleons we obtain the ratio $|G_{E}/G_{M}| = 1.49 \pm 0.23 \pm 0.30$