bluuebunny/crossref_metadata_2025 huggingface dataset:
AQP0 is a novel surface marker for deciphering abnormal erythropoiesis
Authors: Wang Tso-Fu , Lin Guan-Ling , Chu Sung-Chao , Chen Chang-Chi , Liou Yu-Shan , Chang Hsin-Hou , Sun Der-Shan
Published: October 2020

BackgroundHematopoiesis occurs in the bone marrow, producing whole spectrum of blood cells to maintain homeostasis. In addition to light microscopy, chromosome analysis, and polymerase chain reaction, flow cytometry is a feasible, fast, and quantitative analysis method to examine hematological diseases. However, because the lack of sufficient specific cell markers, dyserythropoiesis diseases are not easy to be identified by flow cytometry. Methods: Bone marrow samples from C57BL/B6 mice and one healthy donor were analyzed using traditional 2-marker (CD71 and glycophorin A) flow cytometry analysis. After cell sorting, gene expression of membrane proteins in early and late erythropoiesis precursors and in non-erythroid cells were characterized using microarray analysis. Results Among characterized gene candidates, aquaporin 0 (AQP0) expresses as a surface protein in early and late stage erythropoiesis precursors and is not expressed on non-erythroid cells. In this present study, with assistant of AQP0 staining, we can define up to 5 stages of erythropoiesis in both mice and human bone marrow using flow cytometry. In addition, because patients with dyserythropoiesis generally displayed a reduced population of APQ0 high cells as compared to the normal subjects, analyses results also suggested that the levels of APQ0 high cells in the early erythropoiesis may serve as novel biomarker to distinguish normal versus dysregulated erythropoiesis. ConclusionsAQP0 was successfully demonstrated as an erythroid differentiation marker. The expression levels of AQP0 are down-regulated in patients with dyserythropoiesis, implicating a critical and functional role of AQP0 in erythropoiesis. Accordingly, the levels of AQP0 high population in early erythroid precursor cells may serve as a reference parameter for diagnosing diseases associating with dyserythropoiesis.
Single-Cell Transcriptomic Profiling and Characterization of Endothelial Progenitor Cells: New Approach for Finding Novel Markers
Authors: Abdelgawad Mohamed Essameldin , Desterke Christophe , Uzan Georges , Naserian Sina
Published: October 2020

Background: Endothelial progenitor cells (EPCs) are promising candidates for the cellular therapy of peripheral arterial & cardiovascular diseases. However, hitherto there is no specific marker(s) defining precisely EPCs. Herein, we are proposing a new in-silico approach for finding novel EPCs markers. Methods: we assembled five groups of chosen EPCs-related genes/factors using Pubmed literature & gene ontology databases. This shortened database of EPCs factors was fed into publically-published transcriptome matrix to compare their expression between endothelial colony-forming cells (ECFCs), HUVECs and two adult endothelial cell types (ECs) from skin and adipose tissue. Further, the database was used for functional enrichment on mouse phenotype database and protein-protein interaction network analyses. Moreover, we built a digital matrix of healthy donors' PBMCs (33 thousand single cell transcriptomes) and analyzed the expression of these EPCs factorsResults: Transcriptome analyses showed that BMP2,4 & ephrinB2 were exclusively highly expressed in EPCs; the expression of neuropilin-1 & VEGF-C were significantly higher in EPCs & HUVECs compared with other ECs; Notch 1 was highly expressed in EPCs & skin-ECs; MIR21 was highly expressed in skin-ECs; PECAM-1 were significantly higher in EPCs & adipose ECs. Moreover, functional enrichment of EPCs-related genes on mouse phenotype and STRING protein database has revealed significant relations between chosen EPCs factors and endothelial & vascular functions, development and morphogenesis, where ephrinB2, BMP2 and BMP4 were highly expressed in EPCs and were connected to abnormal vascular functions. Single cell RNA-sequencing analyses has revealed that among the EPCs regulated markers in transcriptome analyses: i-ICAM1 & Endoglin were weekly expressed in the monocyte compartment of peripheral blood; ii-CD163 & CD36 were highly expressed in CD14+ monocyte compartment whereas CSF1R was highly expressed in CD16+ monocyte compartment; iii-L-selectin & IL6R were globally expressed in the lymphoid/myeloid compartments; iv-interestingly, PLAUR/UPAR & NOTCH2 were highly expressed in both CD14+ & CD16+ monocytic compartments. Conclusions: The current study has identified novel EPCs markers that could be used for better characterization of EPCs sub-population in adult peripheral blood and subsequent usage of EPCs for various cell therapy and regenerative medicine applications.
Enhanced Renoprotective Effect of GDNF-Modified Adipose Derived Mesenchymal Stem Cells on Renal Interstitial Fibrosis
Authors: Li Shulin , Wang Yanping , Wang Zhuojun , Chen Lu , Zuo Bangjie , Liu Caixia , Sun Dong
Published: October 2020

Background: The therapeutic effect of Mesenchymal stem cells (MSCs) from human adipose tissue on renal interstitial fibrosis has been demonstrated by several groups. However, the way to enhance the renoprotective effect of Adipose Derived Mesenchymal Stem Cells (AMSCs) and the possible mechanisms, are still unclear. The present study aimed to determine whether glial cell line-derived neurotrophic factor (GDNF)-modified AMSCs holds an enhanced protective effect on renal fibrosis. Methods: AMSCs were isolated and purified for culture. GDNF gene was constructed to transfect into AMSCs. The ability of AMSCs and GDNF-AMSCs supernatants to promote tube formation of endothelial cells, repair damaged endothelial cell junctions and improve endothelial cell function was compared by tube formation assay, immunofluorescence techniques and vascular ring assay, respectively. Furthermore, HE and Masson staining were used to observe the histological morphology of the kidney in vivo. Peritubular Capillary Changes were detected and analysed by Fluorescence Micro-angiography (FMA). Meanwhile, the endothelial cell, hypoxia, oxidative stress, fibrotic markers and PI3K/Akt pathway proteins were measured by western blot or qRT-PCR technics. Results: Studies in vitro demonstrated that compared with AMSCs only, GDNF-AMSCs could better repair injured endothelial cells and promote angiogenesis through secreting more growth factors in the supernatant of GDNF-AMSCs culture media. Studies in vivo, unilateral ureteral obstruction (UUO)-induced fibrotic mice were injected with transfected AMSCs through their tail veins. We showed that enhanced homing of AMSCs were observed in the GDNF-AMSC group compared with the AMSC group. GDNF-AMSCs treated animals exhibited better improvement of capillary rarefaction and fibrosis induced by obstructed kidney compared with the AMSC group. Furthermore, we reported that GDNF-AMSCs protect renal tissues against microvascular injuries via activation of the PI3K/Akt signaling pathway. Therefore, GDNF-AMSCs further ameliorated the tissue hypoxia, suppressed oxidative stress, and finally inhibited endothelial to mesenchymal transition noting by decreased coexpression of endothelial cell (CD31) and myofibroblast (a-SMA) markers. Conclusion: Collectively, our data indicated that the GDNF gene enhances the ability of AMSCs in improving renal microcirculation through PI3K/Akt/eNOS signaling pathway, and afterward inhibit the EndMT process and kidney fibrogenesis, which should have wide implications in designing future remedies for chronic kidney disease (CKD) treatment.
Network sensitivity of systemic risk
Authors: Ramadiah Amanah , Di Gangi Domenico , Lo Sardo D. Ruggiero , Macchiati Valentina , Pham Minh Tuan , Pinotti Francesco , Wilinski Mateusz , Barucca Paolo , Cimini Giulio
Published: October 2020

Amanah , , D. Ruggiero Lo Sardo, Valentina Macchiati, Tuan Pham Minh, Francesco Pinotti, Mateusz Wilinski, Paolo Barucca and Giulio Cimini
A comment on “An evolutionary system of mineralogy: Proposal for a classification of planetary materials based on natural kind clustering”
Authors: Hatert Frédéric , Mills Stuart J. , Hawthorne Frank C. , Rumsey Mike S.
Published: October 2020

The classification and nomenclature of mineral species is regulated by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association (IMACNMNC). This mineral species classification is necessary for Earth Sciences, as minerals constitute most planetary and interstellar materials. Hazen (2019) has proposed a classification of minerals and other Earth and planetary materials according to “natural clustering.” Although this classification is complementary to the IMA-CNMNC mineral classification and is described as such, there are some unjustified criticisms and factual errors in the comparison of the two schemes. It is the intent of the present comment to (1) clarify the use of classification schemes for Earth and planetary materials, and (2) counter erroneous criticisms or statements about the current IMA-CNMNC system of approving proposals for new mineral species and classifications.
Determining the operating parameters of machine systems in potash mines when tunneling with stope back partial section
Authors:   Perm National Research Polytechnic University, Ozornin Mikhail S.
Published: October 2020

Introduction. Heading and winning machine system operation has been considered in the conditions of the Upper Kama (Verkhnekamskoe) potassium and magnesium salt deposit. Excavation of producing formations with the thickness of more than 4 m is carried out in two moves. The lower layer is excavated by the second move, while the area of the stope back is usually less than the cross-sectional area of the machine’s executive body. In this case, the heading and winning machine does not have a full face. Typical calculation methods contain no information for determining the operating parameters of machine systems at potash mines when tunneling with stope back partial section. Research methodology. The methodological foundations of a machine system capacity determination in the conditions of the Upper Kama potassium and magnesium salt deposit are described. The calculation of the main parameters characterizing the operation of the machine system when tunneling with stope back partial section. Results. Based on the identified dependencies, it is possible to determine the rational type of machine system equipment, the rate of hauling the machine to the face, and rational delivery distances based on equipment type and geological conditions. Summary. The proposed method of a machine system’s operating parameters determination in potash mine when tunneling with stope back partial section can be adapted and used in potash mines with various mining and geological and mining conditions to determine the capacity of machine systems.
Study of hydrogeological conditions to ensure security of mining at Sokolovsky iron-ore deposit
Authors:   Institute of Mining UB RAS, Dalatkazin Timur Sh. , Kaiumova Alfiia N. ,   Ural State Mining University
Published: October 2020

Introduction. Complex hydrogeological conditions of the rock mass at Sokolovsky deposit are the cause of constant search for new solutions for industrial safety improvement. At the present time there is much information on engineering and geological conditions of the field rock mass which is a source of measures developed to ensure industrial safety and technological solutions in mining. Research aim. With the purpose of determining a tactics of mining security support, the information on the hydrogeological and engineering-geological conditions of Sokolovsky field was analyzed. Methodology. The article provides the details of Sokolovsky field structure. The factors have been revealed which are hazardous for mining: undrained hydrogeological horizons and complexes, karst, thixotropic rock within the open pit. These factors create the conditions for sludge and water accumulation and rush into the underground mine. The majority of sandshale rushes fall upon the main production horizons into the intake and transportation mine workings. Results. Directions have been determined for further investigation of the mechanism of hazardous phenomena development and realization in geological environment of the field; the investigation is directed at improving catastrophe prevention measures and personnel security measures. Summary. Currently, at the stage of field development, there emerged a need to study particular hydrogeological and geomechanical conditions in details in order to increase of effectiveness of drainage at local sites of the mass which are designed for ore extraction.
The periodic system of chemical elements solid model in the geological aspect
Authors:   Siberian Federal University, Labushev Mikhail M. , Labushev Timofey M. ,   Saint Petersburg National Research University of Information Technologies, Mechanics and Optics
Published: October 2020

The topicality of the research comes from the need to obtain new knowledge about the manifestation of the periodic law in nature. Research aim is to associate the periodic system of chemical elements with the chemical composition and structure of natural objects. The research method suggests the creation of a solid model of the periodic system of chemical elements along with its comparison with ore formation objects as well as the manifestation of chemical elements isomorphism and some natural processes geochemistry. Research results. The solid version of the periodic table of the first 95 chemical elements together with a conventional zero element is proposed. Each volume cell characterizes a chemical element with an elementary crystal lattice of simple substance. Similar models can be composed of minerals and rocks associating with material substance of the earth's crust. 16 vertical groups in the model are arranged in a snake-like pattern. The model of the earth's crust with the “cubes” of chemical elements, minerals and mineral associations is proposed. The elements of adjacent spatial groups are naturally concentrated in combination, showing isomorphism while minerals enter the crystal lattice. The relative position of adjacent “cubes” follows the rule of translation in mutually perpendicular directions. The chemical elements of the first group can correspond spatially to volcanoes as well as mud volcanoes. The place of the zero chemical element is considered to be occupied by the elements of adjacent spatial groups. It is assumed that the faces of the “cube” of chemical elements are permeable areas through which chemical elements can be transferred. Summary. The confirmation of the model follows while considering ore formations, isomorphism of chemical elements in minerals and geochemistry of volcanic processes. 46 "Izvestiya vysshikh uchebnykh zavedenii. Gornyi zhurnal". No. 1. 2020 ISSN 0536-1028 Key words: chemical elements; solid model of periodic system; ore formations; isomorphism in crystals; geochemistry of volcanic processes.
On the seismic activity of the Upper Kama potassium salt deposit
Authors:   Vladimir State University, Filatov Vladimir V. , Bolotnova Liubov A. ,   Ural State Mining University
Published: October 2020

Introduction. The exploitation of the earth's subsoil on an industrial scale leads to a disturbance of equilibrium state of the geological environment and, as a consequence, to the manifestation of various dynamic events in it: sinkholes, rockbursts, induced earthquakes of various magnitudes, etc. Therefore, the problem of predicting such events or phenomena becomes urgent. About two dozen factors determining the state of geological environment and its dynamic regime have been identified in the course of solving this problem for the territory of Upper Kama (Verkhnekamskoe) potassium salt deposit (VKMKS): structural, tectonic, geomorphological, hydrogeological, hydrochemical, geophysical and others. Based on these factors-features, the zoning of the VKMKS territory was performed and the areas most likely for dynamic events manifestation were established. Among the factors-features stand out the dynamic events, which directly indicate the disturbance places of the geological environment’s equilibrium state. Among the features are the following: number and type of events, epicenters position, their relationship with the structural-tectonic elements of the geological environment’s structure and, first of all, with active faults. The purpose of this work is to compare the characteristics of a dynamic event that occurred in the area of SKRU-2 (Solikamsk mine-2) in 1995, with the geological structure of this area. Research methodology. The results of geological and geophysical studies carried out on the territory SKRU-2 are summarized, the characteristics of tectonic rockbursts are analyzed and the structuraltectonic and seismic data were compared. Research results. The structural-tectonic diagram of SKRU-2 territory was constructed and the relationship between the dynamic event and the structural features of the SKRU-2 territory was evaluated. Summary. The comparison of tectonic rockbursts characteristic and the structural-tectonic location of SKRU-2 territory has shown that the mine area is a nodal structure formed by active faults and complicated by fracture zones. Therefore, the probability of dynamic event focus development in such conditions is very high.
Energy and power factors of selective destruction of ores
Authors:   Consulting and Analytical Centre “Russian Standard”, Khopunov Eduard A.
Published: October 2020

The aim of the work is to assess the factors that determine the effectiveness of devices used at different stages of ore processing. The nature of the destruction at each stage is determined by different parameters, therefore, it is so important to search for information factors that allow evaluating the response of mineral raw materials to external influences at the stages of ore preparation. The research methodology is based on the analysis of energy and power factors, which can be correlated both with the loading device and with the body being destroyed. Force factors characterize the response of a material to damaging effects, for example, the limiting amount of resistance to deformation is estimated by the force at which the destruction occurred. The results of the analysis of the role of energy and power factors are given on the example of a selfgrinding mill, a centrifugal crusher, and others. The effectiveness of the self-grinding mill is determined by the ratio of energy and power parameters in the processes of ore lumps kinetic energy conversion into the energy of elastic and breaking strains of the crushable (and crushing) material. It is shown that 88 "Izvestiya vysshikh uchebnykh zavedenii. Gornyi zhurnal". No. 1. 2020 ISSN 0536-1028 the efficiency of centrifugal crushers is ensured by the high intensity of collisions of a multitude of particles, which initially possess excess kinetic energy. In devices such as a roller-press or a cone inertial crusher, the final phase of destruction is associated with volumetric deformation of the layer. This means that the final stages of destruction are completely determined by the structural and strength characteristics of the feedstock and its particle size distribution. The field of application of the presented results are technologies in which the liberation of minerals during ore destruction is considered as a process of structure transformation based on the principles of rational ore preparation. The properties of ores, energy and force factors are important informational parameters of the analysis and selection of methods of destruction during the liberation of minerals. Examples of successful and unsuccessful use of a roller press as a device for reducing the energy consumption for ore preparation are explained within the framework of ideas about the relationship between energy and power factors.
The competitiveness of gold fields
Authors:   Institute of Economics UB RAS, Balashenko Valerii V.
Published: October 2020

Relevance. Russia currently ranks third in terms of global gold extraction and production, and the Urals is considered the birthplace of gold mining in Russia. Gold supply of Ural enterprises nowadays makes up 20–30 years of underground mining and 30–40 years of opencast mining. Reserves increment in Russia is mostly observed at primary deposits, while extraction from placers decreases continually. At the same time, gold prices rise creates prerequisites for the involvement of reserve gold fields into operation. Insufficient financial resources often make the development of new fields impossible; access to the most promising projects, the highly competitive gold fields, is the first priority for potential investors. Research aim is to develop a methodological approach to the assessment of competitive gold fields at the stage of pre-investment study and its approval in the conditions of certain fields. Research methodology includes the benchmarking method, analogue method, and the techno-economic assessment. Results. In the course of research the main obstacles for the development of new gold fields were revealed. It has been proved that the crucial aspect of miners’ competitive advantages is the cost of crude minerals based on in-place reserves and non-commercial reserves, hard rock and other rock in dumps, valuable components in tailings, etc. A formula calculating aggregated cost of the object is proposed, and the competitiveness of the revived Peshchernoe gold field is compared with three newly developed fields of Altyntashskoe, Shilovskoe, and Iagodnoe. Based on the basic indicators of field mining, the cost of mineral raw material was calculated making it possible to rank the compared fields as far as the degree of competitiveness is concerned. Summary. The analysis has shown the gradual deterioration in the quality characteristics of gold fields with the accumulation of refuse mass. Institutional barriers and insufficient financial resources of subsoil users prevent from introducing new fields. Small and medium-sized mining enterprises’ competitive growth requires: introduction and development of land provision declarative principle for geological exploration; simplified procedure of timberland registration for subsoil use; introduction of tax benefits and simplification of subsoil usage procedures as for technogenic objects; creation of favorable investment environment; improved mechanisms aimed at integrated cluster development.
Analysis of connections and restrictions occurring due to the oscillations of vibrating screen working member and cantilevered screen deck
Authors:   Ural State Mining University, Iudin Arkadii V. , Shestakov Viktor S. ,   Ural State Mining University
Published: October 2020

Research relevance is due to the need of mining companies in a more complete extraction of mineral resources, reduction of crude minerals losses, and extension of deposits’ life. Some enterprises face the problem of complicated high-quality separation of hard-to-screen rock mass. Screen which are common in the industry often become clogged causing decline in the effectiveness of screening. Research aim is to determine the links, build resonant curves and analyze the amplitude oscillations of the working member and cantilevered bars of the screen deck using numerical simulation. Methodology includes the theoretical study of the dual mass oscillatory system with the use of numerical simulation. Results. The motion of the vibrating screen with circular oscillations of the working member, which includes the screen deck of a cascade type with cantilevered bars, is regarded as oscillation of a dual mass system. The amplitudes of oscillations of both masses make in-phase and anti-phase movements relative to the driving force of the drive. The analysis showed that the amplitudes of the working member are practically independent of the screen deck parameters, and bars oscillation amplitudes vary over a wide range. The expressions are given calculating the parameters of cantilevered bars and the values of the initial data of the GIT-51 screen. Resonance curves of amplitude and frequency relations are constructed. The conditions are established under which the oscillation amplitudes of the cantilevered bars take on hyperadmissible values; it is shown that for a particular oscillating system there is a transitional resonance value. Summary. The natural oscillation frequency ratio ranges are established of the entire system with the frequency of forced oscillations in which the oscillation amplitudes of cantilevered bars reach the specified parameters. It is shown that by changing the screen deck parameters at the design stage, it is possible to adjust the inter-frequency range and establish the operating mode of the screen.
Review of structural battery designs used on mine electric locomotives
Authors:   Donetsk National Technical University, Gutarevich Viktor
Published: October 2020

Introduction. The use of alkaline and lead-acid batteries in electric locomotives of mining enterprises is currently relevant. There is a need to study the requirements for mine electric locomotives and identify the advantages and disadvantages of electrochemical systems. Research aim is to conduct a comparative analysis of the applied electrochemical systems of mine locomotives, consider the advantages and disadvantages of batteries used in mine electric locomotives, and consider the processes that occur when charging and discharging batteries. Methodology. A review of existing electrochemical systems used on electric rolling stock in the conditions of mine workings is carried out. The processes of charge-discharge of alkaline and lead-acid batteries are considered. Results. This article analyzes the electrochemical systems used in mine electric locomotives, of which two can be distinguished. Lead-acid batteries have a number of significant drawbacks that limit their operating conditions. Alkaline batteries are more widely used as an energy source for mine electric locomotives. Findings. The main types of electrochemical systems used in mine locomotives are highlighted. Their main advantages and disadvantages are examined, from which it follows that the data on the type of batteries operate using caustic substances, which requires additional measures to ensure safe operation.
Increasing mining dump trucks operation efficiency with the use of gas piston engines
Authors:   Ural State Mining University, Khazin Mark L. , Furzikov Vitalii V. ,   Ural Diesel Engine Plant, Tarasov Petr I. ,   Perspektiva-M
Published: October 2020

Research aim is to analyze the prospects for increasing the efficiency of heavy-duty mining dump trucks operation through the use of natural gas as the main energy carrier. Research methodology included bench tests of a gas piston engine (GPE) KAMAZ mod. 820.60-260 with a capacity of 191 kW and the construction of forecast values of GPE parameters for the BELAZ-75319 mining dump truck with a load capacity of 240 tons. Results. A mathematical model and technique have been developed that allows predicting the main parameters of a gas piston engine and optimizing its economic and environmental characteristics. The use of natural gas as a motor fuel, with an unchanged engine design, leads to a decrease in its power. Currently, gas modifications are being created on the basis of existing diesel engines, and it is not always possible to implement any design measures at this stage. To realize all the capabilities of a gas engine, it should initially be designed for gas motor fuel. This technique is based on the experimental data of low-power gas piston engines and can be used for high-power gas engines studies intended for installation on mining dump trucks. Conclusions. Increasing the efficiency of mining dump trucks in the near future is possible through the use of natural gas as the main energy carrier. The use of natural gas as a motor fuel allows to increase the life of the engine, reduce the noise level and toxicity of exhaust gases, and reduce fuel costs.
Modernization of the GISL screen exciter in conversion to new operating mode
Authors:   Siberian Federal University, Diakonova Vera Ia. , Kalinovskaia Tatiana ,   Siberian Federal University, Diakonov Maksim N. ,   Company М2М-Telematika Siberia, Volchkova Irina V. ,   Siberian Federal University
Published: October 2020

Research aim. The article considers the kinematic and dynamic parameters of the screen GISL-62 in order to improve the device for exciting mechanical vibration and the effective use of the screen because of the ISSN 0536-1028 «Известия вузов. Горный журнал», № 2, 2020 107 need to transfer it to the operation mode with increased frequency of vibrator shafts rotation and reduced amplitude of the box vibration. Research methodology. Methods of analytical research with the elements of dynamic and kinematic synthesis are used to specify the adjustment of the screen with the necessary kinematic parameters. Results. The studies of the differential equation of the steady-state screen motion are carried out to obtain the required amplitude of the screen box oscillations and the vibrator shaft rotation frequency. The necessary disturbing force created by the vibrator, the value of static moment of unbalance, the required number of vibration dampers in the screen box supports, the calculated power of motors and other parameters of the vibrator operation mode are determined. The strength and rigidity of the vibrator shafts is calculated considering the significant exciting forces created by the unbalance. The coefficient of the screen dynamics is calculated. Conclusions. The questions connected with defining parameters of the screen, necessary to transfer to a new operation mode are comprehensively settled.
Analysis of the stressed-deformed condition of the bearing installed
Authors:   Ural State Mining University, Maiorov Stanislav , Lagunova Iuliia ,   Ural State Mining University
Published: October 2020

Introduction. The article considers the calculation of the strength of a bearing mounted on the connecting rod of a jaw crusher, taking into account all workloads. ISSN 0536-1028 «Известия вузов. Горный журнал», № 3, 2020 117 Object problems. When creating particularly large machines and systems, in the case of their 3D-modeling and detailed study, we are faced with an increased load on the central processor of the computer, as well as on the graphics and RAM modules, which leads to a significant slowdown in the design process and calculations particular. Research aim is to consider the task of selecting a simpler and "easier" for the calculation model programs, not difficult to parameterize, compared with the original bearing model, but providing accuracy in the calculation in an acceptable range of errors. The research also aims to analyze the stress-strain state of the bearing assembly. The main methods. In the calculations, the finite element method was used. Specialized software package APM WinMachine was also used. Computing experiment conducted. Conclusions. The results of a computational experiment satisfy the requirements and can be used to solve further problems of designing bearing assemblies. In the future, a parameter-dependent model can be created to facilitate the calculation using any type of bearing
Humanities in a technical institution of higher education (by the example of modern fiction)
Authors:   Ural State Mining University, Valentina Kardapoltseva
Published: October 2020

Introduction. Modern rapidly advancing society requires engineers to be active and creative when solving engineering problems, be able to overcome stereotypes being guided by the needs of growing and changing economic reality, which is due to the demands of times and essential condition of the 21st century engineer formation. Modern education should not only be significantly updated with the range of information technologies, but also be guided by the idea of the synthesis of scientific knowledge and humanities where fiction is of no small importance. Research aim is to integrate education and good breeding by means of fiction, form world view and need for personality rich in spirit, socially mobile with self-respect and able to fulfill personal abilities both in scientific and humanitarian directions. Methodology. Hermeneutical method has been applied to analyze fiction by various authors and to interpret such notions as plot, idea, problems, and imagery. Empirical method material has been the fiction of different countries important by research goal and some striking features identification and comprehension. Contextual method has made it possible to delve into the contents of the analyzed literature. Results. It has been proved that the world of fiction forms a citizen, a highly cultured person, promotes the development of heuristic thinking, aesthetic sense and ideals, extends the frontiers of engineering art and ISSN 0536-1028 «Известия вузов. Горный журнал», № 4, 2020 133 ensures new grad’s adaptation in the conditions of economy and market relations. Fiction also promotes the formation of the students’ need in personal growth and assertiveness as an independent creator and a particular personality
Assessing the efficiency of a complex of geophysical methods of rock mass research under the conditions of an underground mine
Authors:   Institute of Mining UB RAS, Vitalii Melnik , Timur Kharisov ,   Institute of Mining UB RAS, Aleksei Zamiatin ,   Institute of Mining UB RAS, Olga Kharisova ,   Institute of Mining UB RAS
Published: October 2020

Introduction. At present, geophysical methods of rock mass research have found wide application in mining and Earth sciences. They are used to perform prospecting and evaluation work in the massif, namely, to identify structural irregularities, voids and various contact zones of the media with sufficient accuracy. The accuracy of the results obtained depends on the method used in particular conditions, the nature and parameters of the target, the external conditions of the natural experiment, as well as the tasks set in the work. Research methodology. The work included a set of geophysical studies, namely, methods of spectral seismic profiling and GPR in an underground mine. Measurements were made to find different objects at different angles to the object in question in order to determine the distance to it. Research results. As a result of investigating with a complex of geophysical methods, a metal shelf was found under the bulk rock mass and two shelf tiers were subsequently separated when carrying out vertically directed measurements. In the process of searching for the underlying excavation in the massif during vertically directed geophysical measurements, which were carried out in the horizontal excavation 20 meters from the shaft, changes in spectrum density at a depth of about 55 m were detected, which coincides with the actual location of the sought excavation. The results of cavity search in rock mass when making measurements at an angle to the object sought showed that there are no sufficiently clear boundaries and it is impossible to estimate the distance to the cavity in the filled stopes.
Study of physical and mechanical properties of working blades material effect of the noise from the mine axial fan
Authors:   Ural State Mining University, Liudmila Kochneva , Vitalii Tauger ,   Ural State Mining University, Evgenii Volkov ,   Ural State Mining University
Published: October 2020

Introduction. The high level of sound pressure created by an industrial axial fan negatively affects the performance of people, leads to a decrease in attentiveness, and provokes production errors. The desire to use small-sized and high-performance turbomachines leads to the need to find ways to create ventilation units with a reduced noise level. Research methodology. One promising way to influence the noise characteristics of axial machines is to prevent resonant vibrations of the working blades due to the manufacture of a material with calculated physical and mechanical characteristics. To date, a mathematical model of the blade as an elastic element has been constructed, which allows us to determine the frequency of its own vibrations. Comparison of this ISSN 0536-1028 «Известия вузов. Горный журнал», № 5, 2020 107 frequency with the frequency of external influences will allow us to conclude about the probability of entering the blade into resonance with external influences. Results. In order to test the theoretical positions, an experiment was performed in which the sound pressure created by geometrically identical impellers was measured: aluminum, which is included in the fan delivery, and composite. Conclusions. It was found that equipping the fan with a wheel with composite blades can significantly reduce the sound level, which confirms the prospects for creating low-noise axial fans by making working blades of a material with calculated physical and mechanical characteristics.
Method of assessment and prediction of overvoltage caused by single-phase arc ground short circuits in the 6–10 kV mains, as a way of increasing the electrical safety level in mining facilities
Authors:   Siberian Federal University, Roman Kuzmin , Ilia Kuzmin ,   Siberian Federal University, Vitalii Menshikov ,   Siberian Federal University, Sergei Kuzmin ,   Siberian Federal University, Valerii Kulikovskii ,   Siberian Federal University
Published: October 2020

Introduction. Overvoltage caused by single-phase ground short circuits are the main reason of multiple breakdowns of insulation. Assessment and forecast of overvoltage in SPGSC in the 6–10 kV mains is therefore a relevant task, and the solution to this problem will make it possible to select effective methods and means of limiting overvoltage and improve the conditions of electrical safety. Research aim is to improve the methods of assessing and forecasting overvoltage of arch SPGSC in the 6–10 kV mains of mining facilities. Methodology. This article provides analysis of current hypothesis and methods for the assessment of overvoltages in the single-phase ground short circuit (SPGSC) mode. Currently the hypothesis of Peterson, Peters–Slepyan, Belyakov–Djuvarl does not fully reflect the factors that affect the maximum overvoltage emergence of the single-phase arc ground short circuits in the 6–10 kV mains, because they don’t take into account the capacitive current value of SPGSC, arc combustion conditions, lifetime of SPGSC, inductance of engines and transformers. Results. There have been obtained dependences that show the dependences of frequency with which overvoltage happens from the factors that were mentioned above. The shown dependences can be used for calculation and assessment of overvoltage in the 6–10 kV mains with different neutral modes to justify the need for activities that will protect electrical systems, transformers, electrical engines from overvoltage in the SPGSC mode and considering its lifecycle. Summary. It was established that from the electrical safety positions of 6–10 kV mains with resistive or combined modes of neutrals on mining and extractive facilities create conditions for the safer exploitation of technological complexes, facilities and electrical equipment, because it can reduce maximum overvoltage ratios by half and thus reduce the number of repeated breakdown of insulation in the SPGSC mode.
Elimination of diatomite dust in the longwall extraction section of the Sig mine in western Algeria
Authors:   Peoples’ Friendship University of Russia (RUDN University), Abdessattar Lamamra , Dmitriy Neguritsa ,   Sergo Ordzhonikidze Russian State Geological Prospecting University
Published: October 2020

Research relevance. Dust generated by mining machines due to continuous loading and transport equipment movement especially in mines with no optimal ventilation conditions is a major problem for decision-makers. Dust directly affects mine capacity and exposes workers' lives to a risk of chronic disease due to the inhalation of large quantities of this dust and toxic gases during a seven-hour or eight-hour shift. Dust control methods in longwall mines vary from one mine to another, depending on ore composition. Research aim. In this article we will examine the current flow process of eliminating dust in the longwall working section and propose another process to ensure optimal working conditions in the diatomite mine. Methodology. Analysis of the technical equipment which is currently used in mining and geological operations and evaluation of its application at the facility under study represents a relevant approach to production efficiency improvement. The present research considers the possibility of using the floodedbed scrubber system which was mainly used in underground coal mines to monitor dust in the longwall section. It has been evaluated how efficient the scrubber absorbs the dust generated as a results of the mineralized layer extraction, the concentration of the coal dust in the working section making up from 0.7 to 8.8 mg/m3, while the dust produced during the extraction of the mineralized layer in the underground diatomite deposit is 0.38–1.21 mg/m3 in the working section. Research results. The research resulted in the positive attitude towards the possibility of applying the flooded-bed scrubber, which is used in coal mines, at the longwall extraction sections of the Sig mine. It will significantly reduce the concentration of dust in the longwall section. Conclusion. In order to set the appropriate working environment inside the mine, an effective method of removing dust must be developed, it is especially important to remove dust during work, which will contribute greatly to boosting productivity and reducing diseases among workers.
Rating the speed of the shearer’s electric motor drive load automatic control
Authors:   Tula State University, Dmitrii Shprekher , Gennadii Babokin ,   National University of Science and Technology MISIS, Evgenii Kolesnikov ,   Novomoskovsk Institute (branch) of Dmitry Mendeleev University of Chemical Technology of Russia, Aleksandr Zelenkov ,   Tula State University
Published: October 2020

Introduction. It is possible to improve productivity, effectiveness, and cost-efficiency of coal extraction due to the efficient use of physical resources, technical upgrade of mechanized longwall equipment, and introduction of advanced technologies and control methods. The existing method of shearer electric motor drive automation based on the automated load controller of Uran type has a significant drawback of low speed. In case the actuator (A) meets solid rock and the shearer’s (S) speed is not changed, it may result in heavy shock loads on A and its transmission, therefore, increased wear of the cutter or machine’s breakage, leading to production loss due to the reduced speed of travel along the face. The foregoing demands higher standards of the load controller’s speed, making the task of improving the control system’s development a relevant scientific task. Research aim is to synthesize the neural tuner for the coefficients of the proportional-integral controller (PI controller) in the control system of a shearer with increased speed as compared to the existing standard controllers. The research also aims to estimate its efficiency by the method of mathematical simulation. Methodology. Mathematical model has been developed which has made it possible to compare the performance of standard controllers with an adaptive PI controller. The structure and parameters of the neural network underlying the controller have been substantiated. The proposed controller was compared to the standard PI controller and to the MPC controller (microprocessor-based speed controller) by the method of simulation experiment. Research results. The adaptive PI controller has been synthesized based on the neural network which allows changing the coefficients of the PI controller as soon as coal strength changes. Summary. The simulation experiment has shown that the PI controller with the neural network tuner for its coefficients in the control system will make it possible to increase the load controller’s speed by 1.5 to 3 times on average as compared to the classical controller. Therefore, it is going to be possible to avoid critical overload and breakage of mechanical parts in the shearer’s transmission in case of the sudden contact of its actuator with solid inclusion.
Technogenic salt karst
Authors: Anatolii Gaidin
Published: October 2020

Introduction. There are the speleological and engineering-geological areas in karst studies. Engineeringgeological area has two aspects, the surface aspect including the construction of surface buildings in the areas with the karst hazard and the subsurface aspect of prevention and protection from karstification when developing mineral deposits. Although shafts in salt mines has been working since the Middle Ages, the salt karst is still the reason for the destruction of a lot of salt mines. Research aim is to reveal the physical and chemical mechanism of salt karst development and the reasons for accidents and flooding in salt mines. Methodology included the analysis of regular survey measurements of surface deformation, recording of brine manifestations in mine workings, chemical analyses in brines, hydraulic measurements at surface watercourses, direct determinations of brine aggression, geophysical research by the natural field method, vertical electrical sounding, etc. In recent years, in order to control surface deformation, the data from the radar survey have been used. Results. A clue to the mechanism of salt karst responsible for accidents is the theory of hydrodynamic systems by A. M. Ovchinnikov, the elements of which are the areas of accumulation, transit, and discharge. Brine motion is in the supra-salt reservoir. The trajectory of brine motion is determined by the relief of the salt table. Pressure flow take up the elevated terrain. Accumulation areas are confined to stream corridors permeating the low-permeability strata which covers the salt. The area of transit distinguishes between the zone of the pressure flow and the vertical slot where the brines move in the gravity turbulent conditions. Mine workings make up the discharge area. Within them under the action of aggressive brines triangular niches develop. Pillars undercut results in their collapse and surface sink. Summary. Salt karst development mechanism disclosure has made it possible to propose the methods for predicting its effect and the ways of predicting flooding in salt mines.
Geophysical signs of hard rock disturbance
Authors:   Mining Institute Kola Science Centre of RAS, A. Iu Diakov
Published: October 2020

Introduction. Development of deep open pits requires reliable knowledge on conditions of rocks at the hard rock mass to locate potentially hazardous sectors which have considerable impact on efficiency and rationality of a deposit’s development. Definition of disturbed zones at the open pit benches is an actual scientific and practical task in terms of supporting stability and functionality of such facilities. Research aim is to study geophysical signs of disturbance of hard rocks by data of nondestructive ground-penetrating radar (GPR) observation of the surrounding rock mass at the working open pit benches in order to estimate their geological structure and differentiate by disturbance degree. Methodology. Nowadays, GPR data is overwhelmingly interpreted based on comprehensive analysis of amplitude, frequency and phase characteristics of an electromagnetic signal and without an attribute analysis of the wave field. When using the structural approach, based on the analysis of the dynamic and kinematic characteristics of the wave field, to identify hard rock disturbance areas, it becomes possible to significantly increase the accuracy of their determination and localization according to the nondestructive subsurface GPR research. Results. Based on GPR measurements, the author has studied geophysical signs of disturbed rock zones identification at the open pit benches which consist in a quantitative estimation of change in reflection response amplitude characteristic, permittivity of a section and Q factor attribute. Conclusion. Using the established relationships with the proposed analysis of geophysical signs, the GPR study data can contribute to the adoption of differentiated and providing greater stability parameters of benches and mining operations.