Mining of Mineral Deposits最新文献

{"title":"Research into the coal quality with a new selective mining technology of the waste rock accumulation in the mined-out area","authors":"D. Malashkevych, M. Petlovanyi, K. Sai, S. Zubko","doi":"10.33271/mining16.04.103","DOIUrl":"https://doi.org/10.33271/mining16.04.103","url":null,"abstract":"Purpose. The research purpose is to study the formation of quantitative-qualitative indicators of mined coal under conditions of dynamic changes in space and time with a new stope mining technology with waste rock accumulation in the underground mined-out area. Methods. The contours are formed for mining low-thickness coal reserves and extracting thicknesses, undercut rock volumes in the stoping and preparatory faces in the conditions of the Heroiiv Kosmosu mine. The average density values of coal, rock layers and wall rocks in the seam within the boundaries of mining contours are determined based on the geological data of wells and mining operations. The graphic basis is executed in the AutoCAD program. A digital spatial model of the С10t seam contours is used, according to the schedule for organizing stope and preparatory operations. The volumes of waste rocks and minerals involved in the formation of quantitative-qualitative rock mass indicators in a given time period are calculated. Findings. It has been determined that during mining of coal reserves from the studied mining area (equal to extraction site), the volume of production and the operational coal ash content in the mining technology with waste rock accumulation averages 376.5 thousand tons and 15.2%, while with traditional technology – 621.3 thousand tons and 46.7%. Nevertheless, it has been proven that in terms of energy equivalent, the value of mined coal using the mining technology with waste rock accumulation is higher by 7.4% than the traditional technology (9.6 TJ versus 8.9 TJ). Originality. For the first time, a mechanism for the formation of operational ash content and energy value of coal has been revealed when combining the processes of drifting operations to prepare reserves from new extraction pillars with associated stope operations into a new selective mining technology with waste rock accumulation in the mined-out area. Practical implications. An algorithm for predicting the operational ash content and quality of coal when using selective mining technology with waste rock accumulation in the mined-out area has been developed, which is important for the technical and economic indicators of coal mines.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45201804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physical and simulation modelling of solid media fracturing by means of explosive charges of different cross-sectional shapes","authors":"O. Ishchenko, V. Konoval, K. Ishchenko","doi":"10.33271/mining16.04.122","DOIUrl":"https://doi.org/10.33271/mining16.04.122","url":null,"abstract":"Purpose is to evaluate experimentally and theoretically a mechanism of solid media fracturing by means of explosive charges varying in their cross-sectional shapes. Methods. The Mohr-Coulomb strength condition has been applied to describe rock transition to the disturbed state. The condition has become a basis to develop a mathematical model of explosion (i.e. shock and detonation wave) of the concentrated borehole charges. The simulation explosion was modelled while adequate load applying at the points belonging to the outline of both cylindrical charge and at the charging angles in the shapes of triangular and square prisms. The evaluation mechanism of solid media fracturing by means of explosive charges, varying in their shapes, used the models made of optically active materials. A method of high-speed photorecording of the process was involved; the method was combined with the photoelastic technique of stress analysis. Findings. Taking into consideration rock transition to the disturbed state, the Mohr-Coulomb strength condition was applied with the possibility to simulate failures resulting from shear as well as from separation according to the developed mathematical model. The calculation results have helped identify distribution of a geomechanical parameter (Q) at different time points (time iterations). Dependencies of changes in the maximum component of the main stress tensor σ1 / γН along the axis passing through the charge centres perpendicularly to its flat surface for different time iterations have been developed. It has been defined that the maximal stresses are concentrated on the top of both triangular and square prisms helping shape a denser crack network within the zones. Originality. It has been identified that at the initial explosion stage, the maximum values of the main stress tensor component σ1 / γН along the axis passing through the charge centre perpendicularly to its flat surface, experience certain change depending upon a power law with the increasing distance to the charge outline. At the same time, if the charge is of a square prism shape then time iteration being i = 5 makes the main stress decrease according to a linear dependence. Practical implications. The research may be used as the basis for the development of rational parameters of the resource-saving methods applied to separate hard complex rocks in terms of open pits where building materials are mined.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42626229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research into the influence of the thin ore body occurrence elements and stope parameters on loss and dilution values","authors":"Yerdulla Serdaliyev, Yerkin Iskakov, Bagdat Bakhramov, D.E. Amanzholov","doi":"10.33271/mining16.04.056","DOIUrl":"https://doi.org/10.33271/mining16.04.056","url":null,"abstract":"Purpose. Development of a methodology for determining the level of actual losses and dilution of ore based on the identified patterns of the influence of occurring ore body elements and the stope parameters when mining thin slope deposits using a system for delivering ore by the blasting force. Methods. The task set is solved using an integrated approach, including the analysis of literary sources and the existing practical experience on the issues of losses and dilution, conducting experimental-industrial experiments in the conditions of the Akbakai deposit to assess the recommended method effectiveness for determining the values of excess losses and dilution of ore, geomechanical assessment of the mass using the methods of limit equilibrium, numerical and probabilistic analyses. Findings. A methodology for determining losses and dilution when mining thin slope deposits using a system for delivering ore by the blasting force is proposed, which makes it possible to predict excess losses and dilution coefficients arising from stope roof caving and incomplete ore delivery. The actual losses and dilution of ores in the Akbakai deposit have been determined based on the proposed methodology and instrumental surveys. The developed methodology for determining the values of excess losses and dilution makes it possible to take preliminary measures to prevent the stope roof caving with the complete ore mass delivery using the blasting force. Originality. New dependences have been revealed for the conditions of the Akbakai deposit: logarithmic – the value of dilution depending on the angle of the ore body occurrence; polynomial – the stope maximum span depending on the ore body dip angle; exponential – ore losses depending on the angle of the ore body occurrence. Practical implications. The practical significance, confirmed in the course of pilot-experimental work, is in minimizing the percentage of loss and dilution of the useful component when mining thin slope ore deposits using a sublevel blast-hole stoping system with an open stope space, which makes it possible to reduce the cost of the produced mineral.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43890248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analytical and numerical study of one-dimensional and two-dimensional stress distribution within an elastic semi-infinite material under the action of an arbitrary rectangular uniform loading","authors":"F. Maleki, H. Chakeri, Sajjad Chehreghani, Hossein Azad Soula","doi":"10.33271/mining16.04.047","DOIUrl":"https://doi.org/10.33271/mining16.04.047","url":null,"abstract":"Purpose. The study of stress distribution within an elastic semi-infinite material under the action of an external loading is of great importance in the theory of elasticity. In most cases, the lack of knowledge about the stress distribution within a material can result in incomplete and inappropriate engineering designs, leading to unsatisfactory consequences. The latter include cracks and fractures, created inside the concrete segmental lining in TBM tunneling, as well as indentations that occur in floors due to the lack of pillar design not only in underground mining, but even in civil projects. This study focuses on the one-dimensional and two-dimensional internal stress distribution induced by arbitrary rectangular–square loading, in other words, that applied to an elastic semi-infinite material. Methods. Firstly, this paper uses an analytical method and, subsequently, a numerical method. In the analytical study, the point load equations of Boussinesq and Westergaard are used. Extending these equations to the rectangular loading area, four new equations are introduced. Using the Abaqus finite element software, the numerical study is performed in 3D space. Findings. The results show that the answers from the introduced equations are in high consistency with numerical ones. However, the result of the extended Boussinesq point load equation is closer to the answer obtained by the numerical method. Originality. Four new equations, presented in this paper, describe one-dimensional and two-dimensional stress distribution. Practical implications. The presented equations can provide a simple and convenient way to solve rectangular load problems in many cases such as foundation, civil and mining projects. This study uses initial information on specific segments in the Tabriz Metro line-2 Project.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43566978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Slope failure characterization: A joint multi-geophysical and geotechnical analysis, case study of Babor Mountains range, NE Algeria","authors":"Leila Boubazine, A. Boumazbeur, R. Hadji, Kessasra Fares","doi":"10.33271/mining16.04.065","DOIUrl":"https://doi.org/10.33271/mining16.04.065","url":null,"abstract":"Purpose. The research purpose is to apply an original combined approach to the study of landslide occurrence in the Tarzoust region, based on geophysical approaches. This is extremely important because landslides damage roads and buildings in many parts of North Africa, especially in the city of Tarzoust, NE Algeria. Significant slope failures have resulted in serious disasters in the region. Methods. In this study we use Vertical Electric Soundings (VES) and Seismic Refraction Method (SRM) for underground exploration, as well as Electrical Resistivity Tomography (ERT) to support the latter two methods. Findings. The clayey nature of the terrain is confirmed, very often covered by a mantle of superficial colluvium formations. The depth of the bedrock and shear surface has been precisely determined. The ERT reveals that the terrain has already experienced instability in the past. Originality. The originality of this study is in the combination of data from various sources and different approaches for the purpose of planning the deployment and use of land. Practical implications. Our approach has proven that the combination of geological and geotechnical data with geophysical deterministic methods can help engineers and decision-makers in land management. Our recommendations consist of topographic, inclinometric and piezometric monitoring for slip development and the effectiveness of reinforcement measures for new housing, and equipment programs for regional planning.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43708724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of the quality indices of coal on its grindability","authors":"D. Miroshnichenko, Valentine Koval, O.V. Bogoyavlenska, S. Pyshyev, E. Malyi, M. Chemerinskiy","doi":"10.33271/mining16.04.040","DOIUrl":"https://doi.org/10.33271/mining16.04.040","url":null,"abstract":"Purpose is to determine the effect of quality indices of coal characterized by different degrees of metamorphism as well as petrographic and ultimate composition on the values of its grindability defined by the Protodyakonov and Hardgrove methods. Methods. 14 coal samples being a part of the raw material base of coking and chemical enterprises of Ukraine were studied. In terms of the samples, the parameters of technical, petrographic, and ultimate analysis were identified. GOST 21153.1-75 Rocks. Method of determining the Protodyakonov strength coefficient and ISO 5074:2015 Bituminous coal. Determination of Hardgrove grindability index were used to identify coal grindability. Graphical and mathematical dependencies between the indices of coal quality (R0, Vdaf, Cdaf, Oddaf) and values of its grindability (f and HGI) were developed. Findings. The obtained mathematical and graphic dependencies of the effect of different indices of coal quality (R0, Vdaf, Cdaf, Oddaf) on the values of its grindability (f and HGI) were obtained. It is shown that dependence of coal quality indices with its strength coefficient (f) is much lower (R2 = 0.550-0.716) than with the Hardgrove grindability index (HGI): R2 = 0.807-0.937. Originality. For the first time, comparative measurements of coal grindability according to the Protodyakonov and Hardgrove methods have been performed. It has been identified that the value of these indices are inversely proportional and described by a second-order polynom. Practical implications. The obtained graphical and mathematic dependencies can be used to predict the operation of crushing equipment for both individual coal and the one of different grade and ultimate composition at coking-chemical and heat-producing enterprises.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41847342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multivariate statistical-based approach to the physical-chemical behavior of shallow groundwater in a semiarid dry climate: The case study of the Gadaïne-Ain Yaghout plain NE Algeria","authors":"Imane Dib, A. Khedidja, Wahid Chattaha, R. Hadji","doi":"10.33271/mining16.03.038","DOIUrl":"https://doi.org/10.33271/mining16.03.038","url":null,"abstract":"Purpose. Several natural and anthropogenic factors control the hydro-geochemical behavior of groundwater. These factors influence on the quality, even the suitability of this resource for drinking. The main purpose of our study is the application of multivariate statistical methods to compile the mechanisms of mineralization acquisition in confined aquifers. Methods. The adopted method measures the chemical evolution of Ca+2, Mg+2, Na+, K+, HCO-3, Cl-, SO4-2, NO-3, NO-2, NH+4, and PO4-3 using an atomic-absorption spectrometer. The content of nitrogen and dissolved oxygen is measured using a spectrophotometer. Temperature (T°), electrical conductivity (EC), pH and dissolved oxygen are determined using a multi-parameter system. Findings. The main results show that 28 water samples from the Mio-Plio-Quaternary aquifer of the Gadaïne-Ain Yaghout plain have chemical facies of chloride, sulfate-calcium and chloride-magnesium types. Originality. The originality of the study is in the demonstration that water acquires its carbonate mineralization at the supply limits. Whereas it acquires its chloride, sodium and sulfate mineralization in contact with terrigenous saliferous formations, as well as in its interaction with the salt chotts formations. The results show a significant variation in the concentrations of chemical elements, in some cases exceeding drinkability standards. Mineralization is mainly caused by the dissolution of evaporitic minerals such as gypsum, halite and epsomite. Practical implications. The practical implications of this study could be resumed in terms of the convenience of multiva-riate statistical evaluation of complex physical-chemical databases in identifying pollution sources and understanding temporal variations for effective groundwater quality management in semiarid regions.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41342020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Methodological principles of the selection of a resource-saving technology while developing water-bearing placer deposits","authors":"O. Lozhnikov, O. Shustov, Maksym Chebanov, T. Perkova","doi":"10.33271/mining16.03.115","DOIUrl":"https://doi.org/10.33271/mining16.03.115","url":null,"abstract":"Purpose. The present paper aims to develop methodological principles for the selection of effective parameters of resource-saving technologies while developing water-bearing titanium-zirconium deposits basing on the complex of analytical studies. Methods. The paper applies a complex of research methods: analytical – to analyze and generalize the main differences of the development technology for water-bearing placer deposits and problem statement; technical-economic analysis for identifying the effect of a resource-saving technology on the indices of land use of the open-pit mining and involvement of associate raw materials in the economic activity; forecasting – to determine the influence on complex development of a titanium-zirconium deposit on the operating parameters of the regional nonmetallic raw material open pits. Findings. Effective trends in using the associate raw materials located in the enclosing and overburden rocks of a titanium-zirconium deposit are identified. Key differences between the technologies of associate raw material mining from the overburden rocks and their recovery from the enclosing rocks while mineral mining are defined. Predictive influence of a resource-saving technology of the development of titanium-zirconium deposits on the extraction of building materials from the regional nonmetallic open pits is specified. Volumes of possible associate raw material mining while developing the Motronivskyi GZK open pit during its operation are determined. Originality. New dependences of a land capacity coefficient while mining nonmetallic raw material in the region, prime cost of ore development as well as number of open pits for sand and clay production in the region on the volumes of involved associate raw material of the titanium-zirconium open pits are identified. Practical implications. A structural-logical scheme is elaborated for the selection of a resource-saving technology while operating open pits for the development of titanium-zirconium deposits.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41402273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An alternative method of methane production from deposits of subaquatic gas hydrates","authors":"V. Klymenko, Serhii Ovetskyi, V. Martynenko, O. Vytyaz, A. Uhrynovskyi","doi":"10.33271/mining16.03.011","DOIUrl":"https://doi.org/10.33271/mining16.03.011","url":null,"abstract":"Purpose. Determination of the potential efficiency of the alternative method of methane production from subaquatic gas hydrate deposits using the emissions of underwater mud volcanoes considering geological and thermodynamic conditions typical for the Black Sea. Methods. Computer modeling of the processes considering changing of the thermodynamic parameters of the supplying fluid within the pipeline and hydrate deposits was carried out on the basis of the Aspen Hysys program, using the Ng and Robinson model to calculate the energy potential of the fluid. Findings. An algorithm for calculating the distance to which a flow of the emissions mud volcano can be delivered with a temperature sufficient to remove sea bed hydrates from thermodynamic equilibrium and release methane has been developed. The schematic technological solution of an alternative method of methane production from gas hydrate deposits were presented by using the energy of emissions of mud volcano (fluid). The collection device for emissions of mud volcano and gas hydrate sea bed deposits were also been used within the model. The calculations have been done using Aspen Hysys computer program. Originality. The potential efficiency of the alternative method of methane production from gas hydrated sea bed deposits using thermal energy from emissions of underwater volcanoes is substantiated. It is also shown that in the case when the hydrate deposits cover the sea bed natural gas deposits as an impermeable layer, the thermal energy of the gas flow extracted from the sea bed natural gas deposits can be used for the decomposition of the hydrates This case is similar to the considered alternative method of using thermal energy of the emissions of mud volcanoes. Practical implications. The use of an alternative method of methane production from gas hydrate sea bed deposits by using emissions of mud volcano make it possible to increase the amount of gas obtained from subaquatic sources ~ by 7-10% without using additional sources of thermal energy. The practical application of this method will also prevent methane emissions from mud volcanoes into the atmosphere, which reduces pollution of seas and oceans with dissolved gases.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42778682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Automated determination of rock crushing zones in the collapse","authors":"B. Rakishev, Z. Rakisheva, A. Auezova, A. Orynbay","doi":"10.33271/mining16.03.109","DOIUrl":"https://doi.org/10.33271/mining16.03.109","url":null,"abstract":"Purpose. Development of an automated method for determining the zones of rock crushing in the collapse in order to select rational technologies for drilling and blasting operations. Methods. Methods for determining the positions of nodal and internal points of the coordinate grid of blasted rock collapse, approximation methods, matrix theory, numerical methods in technology are used. Findings. An automated method for determining the zones of rock crushing in the collapse is described. It is based on an analytical method for determining the granulometric composition of blasted rocks in zones of active and passive crushing. The meth-od correlates the granular composition of the blasted rock mass with blockiness of the rock mass, physical and mechanical properties of the blasted rocks, physical and chemical characteristics of the explosive used, and parameters of charge location in the rock mass. Originality. Based on the joint application of methods for determining the nodal and internal points of the coordinate grid and calculation of rock crushing zones in the blasted block, an analytical method for determining the sizes of rock crushing zones in the collapse was developed for the first time in mining.Based on the joint application of methods for determining the nodal and internal points of the coordinate grid and calculation of rock crushing zones in the blasted block, an analytical method for determining the sizes of rock crushing zones in the collapse was developed for the first time in mining. Practical implications. On the basis of the developed method, a computer program was created for the automated determination of the crushing zones sizes of a blasted block. With the help of this program, zones of small, medium and large crushing of the blasted block can be quickly and fairly accurately determined under various parameters and conditions of blasting rock masses. Locations of the blasted block crushing zones thus established serve as a tool for choosing rational technologies of drilling, blasting, excavating and loading operations, which determines their practical value.","PeriodicalId":43896,"journal":{"name":"Mining of Mineral Deposits","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45653369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}