Power engineering: research, equipment, technology最新文献

{"title":"Improved method for vibration control of the technical condition of a power transformer based on fractal analysis of the amplitude-time characteristics","authors":"V. Basenko, I. Ivshin, O. Vladimirov, M. Nizamiev","doi":"10.30724/1998-9903-2023-25-2-124-136","DOIUrl":"https://doi.org/10.30724/1998-9903-2023-25-2-124-136","url":null,"abstract":"   The purpose of this work is to improve the method of vibration control of a power transformer through the use offractal analysis of the amplitude-time signal.   Fractal analysis of the amplitude-time characteristics will allow to quantify the degree of «indentation» of the vibration signal of the transformer associated with a defect. For a quantitative assessment, the fractal analysis coefficient (FAC) was introduced based on the determination of the fractal dimension by the Hausdorff-Besikovich method. To test the developed method, a non-contact laser measuring and diagnostic complex (LCMC) with developed software based on LabVIEW, ImageJ and Python was used. Experimental studies of the transformer TSZ 16 were carried out using the developed method and LCIK. The CFA of the windings and magnetic circuit of the transformer under study, the level of technical condition for the controlled elements of the transformer are determined.   METHODS. The improved method of control makes it possible to increase the accuracy of control of a power transformer during its operation under voltage, which makes it possible to switch from a planned system of transformer repairs to a system for taking repairs according to the current technical condition.   RESULTS. The improved method of vibration control was tested using the developed non­ contact LCIK, the level of technical condition of the power transformer under voltage was determined.   CONCLUSION. An improved method of vibration control makes it possible to determine the level of technical condition of an energized power transformer with the possibility of automatically obtaining a decision on the technical condition, as well as to use statistical methods for processing and analyzing the signals received from the transformer.","PeriodicalId":222237,"journal":{"name":"Power engineering: research, equipment, technology","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121920576","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":"Synthesis of a parametrically invariant servo drive using the model parameters recovery method","authors":"N. A. Malev","doi":"10.30724/1998-9903-2023-25-2-40-57","DOIUrl":"https://doi.org/10.30724/1998-9903-2023-25-2-40-57","url":null,"abstract":"   RELEVANCE. Servo drives operate with a law of change of the setting action unknown in advance and provide reproduction of this law by the output coordinate. Servo drives find application in robotic and mechatronic systems, machine tools, systems of automatic control and remote transmission of information, radar stations, guidance units, etc. The operation of servodrives often proceeds in conditions of instability parameters and characteristics elements of the electric drive. Corrective devices synthesized by classical methods of automatic control theory cannot cope with providing the specified accuracy of reproduction of the input signal and the required quality of transients.   THE PURPOSE. In this regard, an important and urgent task is the synthesis of an active correction system with a non-stationary controller that provides the required quality and accuracy of the control process due to the coefficient self-tuning algorithm.   METHODS. When solving this problem, methods for identifying parameters based on the gradient algorithm and numerical integration of the object of study dynamics equations, implemented by means of the MatLab software environment, were used.   RESULTS. The paper solves the problem of synthesizing the self-tuning algorithm for the coefficients of the servo drive corrective device based on the identification approach. The parameters are identified by a searchless gradient algorithm while minimizing the discrepancy between the object of study and its inverse model, as well as restoring the coefficients of differential equations using integration and the corresponding computational procedures. An servo drive with negative position feedback is tuned to the modular optimum with a proportional controller whose coefficients are completely determined by the parameters to be identified. The self-tuning algorithm consists in calculating the correction factor of the non-stationary P-controller and forming a multiplicative channel of the active correction closed loop.   CONCLUSION. The simulation of the electric drive in the MatLab software environment showed high accuracy and quickness of the process identifying parameters in a wide range of their change. When forming an active correction contour, a necessary requirement is to distinguish between the identification cycle and the self-tuning cycle. This makes it possible to avoid singular perturbations and reduce resonant facts during the operation of a parametrically invariant electric drive. The developed method of active correction with a priori known and unchanged structure of the object model of study makes it possible to maintain the required accuracy and quality of the operation of the electric drive under conditions of parametric disturbances with permissible deviations of accuracy and quality indicators. Implementation of the method does not require additional equipment, organization of special test signals, significant computational costs. The method of synthesizing a pa","PeriodicalId":222237,"journal":{"name":"Power engineering: research, equipment, technology","volume":"89 36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129796130","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":"Measures to increase the technical resource of electrical equipment of powerful irrigation pump stations","authors":"S. Dadabaev, E. Y. Abdullazyanov, E. Gracheva","doi":"10.30724/1998-9903-2023-25-2-26-39","DOIUrl":"https://doi.org/10.30724/1998-9903-2023-25-2-26-39","url":null,"abstract":"   RELEVANCE. At present, unstressed systems for launching high-voltage electric motors have been increasingly used. These systems limit the values of starting currents as well as eliminate alternating oscillations of engine electromagnetic torque.   THE PURPOSE. Development of measures to improve the technical resource of electrical equipment of powerful irrigation pumping stations based on the use of soft start systems for high-voltage electric motors.   METHODS. In the course of the study, methods for analyzing the technological processes of a pumping station, methods for mathematical and computer modeling of an electric drive were used. RESULTS. Computer models have been developed to study the regime characteristics of asynchronous and synchronous electric drives of pumping stations with direct and soft start of electric motors. A shockless start-up system for high-voltage electric motors of irrigation pumping stations of the first lift based on a current inverter is proposed.   CONCLUSION. The reliability and durability of electrical equipment depends primarily on the technical resource, which is determined by a number of factors. The main factors influencing the technical life of the electrical equipment of large irrigation pumping stations are the transient modes that occur when the pumping units are started. The soft start system of high-voltage electric motors of irrigation pumping stations proposed in this article makes it possible to eliminate the negative impact of transient conditions on the operation of electrical equipment and, thereby, increase the technical resource and reliability of the power supply system of the pumping station as a whole.","PeriodicalId":222237,"journal":{"name":"Power engineering: research, equipment, technology","volume":"710 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116123685","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":"Modeling of thermal power plants in the study of reliability of power supply and energy security","authors":"D. Krupenev, V. M. Piskunova, A. G. Galfinger","doi":"10.30724/1998-9903-2023-25-2-12-25","DOIUrl":"https://doi.org/10.30724/1998-9903-2023-25-2-12-25","url":null,"abstract":"   RELEVANCE. Maintaining the required level of energy security (ES) and reliability of fuel and energy supply is one of the priority tasks in the management of the energy sector. In the functioning of the fuel and energy complex various threats are possible, which can lead to the violation of the reliability of fuel and energy supply and the emergence of shortages ofvarious types of energy resources. To assess the level of energy security, approaches are considered to form a mathematical model of the FEC, which combines all sectors of the energy sector. Despite the trends of transition to low-carbon energy sources associated with energy transformation, thermal power plants remain one of the main sources of heat and electricity.Due to the ability to generate large amounts of heat only thermal power plants can be a source of centralized energy supply of large territories. In this regard, when modeling the fuel and energy complex, it is necessary to develop mathematical models of TPPs, which will correctly reflect the technological processes that affect the reliability of energy supply.   OBJECT. Development of mathematical models of interaction of electric power, heat supply and fuel systems within the framework of thermal power plants designed to study energy security and reliability of fuel and energy supply.   METHODS. Mathematical modeling of fuel consumption dependences on electrical and thermal load at thermal power plants is used as methods. To obtain analytical dependencies, the least squares approximation of the consumption characteristics of thermal power plants was carried out.   RESULTS. As part of the work, analytical dependences of fuel consumption on thermal and electrical load for various types of thermal units were obtained. For all considered steam turbines, linear dependences of theamount of heat supplied to the turbine on its load (electrical and / or heating depending on the type of turbine) were obtained. For boilers, an approximation of the dependence of efficiency on thermal load was carried out. According to the results of the approximation, a linear dependence is assumed. For gas turbine installations, an approximation of the dependence of the efficiency on the load was carried out, according to the results of which a second-order polynomial was obtained.   CONCLUSION. The paper investigates the problem of mathematical modeling of the interconnected operation of fuel, heat and power and electric power systems within the framework of the functioning of the energy sector. Analytical dependences are obtained for different types of generating equipment, including boilers, steam turbines and gas turbine installations. The obtained dependences are necessary for the analysis of energy security and reliability offuel and energy supply. The models of thermal power plants presented in the paper are the most suitable for the analysis of energy security and reliability of fuel and power supply, as they provide the necessary accuracy ","PeriodicalId":222237,"journal":{"name":"Power engineering: research, equipment, technology","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125931755","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":"Mass emissions of polycyclic aromatic hydrocarbons during fuel combustion in thermal power plant boilers","authors":"M. Ivanitskiy","doi":"10.30724/1998-9903-2023-25-2-3-11","DOIUrl":"https://doi.org/10.30724/1998-9903-2023-25-2-3-11","url":null,"abstract":"   RELEVANCE of this study lies in the establishment of technological indicators of emissions of benz(a)pyrene into the atmosphere to assess the degree of negative impact of energy enterprises on the environment and the development on this basis of primary (air protection) measures, inventory of emissions ofpollutants, collection and preparation of initial environmental information for the effective implementation of the principles of technological regulation of emissions in the domestic thermal power industry. THE   PURPOSE. The technological features of the formation of polycyclic aromatic hydrocarbons, in particular benz(a)pyrene, in the furnaces of power boilers burning organic fuel are considered.   The regime factors significantly influencing the intensity of the formation of benz(a)pyrene as the most carcinogenic and mutagenic impurity influe gases have been determined. As part of the implementation of the principles of technological rationing of polluting marker substances, energy enterprises should determine the mass emission of highly toxic combustion products to improve the environmental performance of combustion processes and establish technological emission indicators.   METHODS. Determination of mass emissions of polycyclic aromatic hydrocarbons was carried out using methods of mathematical statistics, processing of environmental information, system analysis of data and processing of the results obtained.   RESULTS. Analytical expressions have been developed to determine the content of benz(a)pyrene in the combustion products of coal and anthracite. The values of mass emissions of benz(a)pyrene for inventory and justification of technological rationing of carcinogenic and mutagenic substances at energy enterprises have been determined.   CONCLUSION. The results obtained are recommended to be used for a preliminary assessment of the content of benz(a)pyrene in the flue gases of boilers at power plants at the stage of collecting and preparing information for the introduction of technological rationing of highly toxic substances and the assessment of technological emission indicators.","PeriodicalId":222237,"journal":{"name":"Power engineering: research, equipment, technology","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116918530","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":"Investigation of rheological properties of composite suspension fuels","authors":"E. Zvereva, G. Mingaleeva, B. R. Valiullin, L. Zverev, M. S. Lipatov","doi":"10.30724/1998-9903-2023-25-1-143-153","DOIUrl":"https://doi.org/10.30724/1998-9903-2023-25-1-143-153","url":null,"abstract":"THE PURPOSE. The features of the rheological behavior of composite fuel oil suspensions depending on the shear rate, temperature and composition of the composite fuel are considered.METHODS. Suspensions with a coal content of 30, 40 and 50% (by weight) were prepared. The mixing time varied from 1 to 10 minutes. The samples of fuel oil were examined using a Rheomat RM 100 rotary viscometer to determine the values of dynamic viscosity at different shear rates and temperature.RESULTS. The results of experimental studies of the dynamic viscosity of fuel oil as a function of the shear rate and temperature are obtained. The best values of coal dust content in fuel oil suspensions for fuel transportation have been determined.CONCLUSION. The obtained research results can be used by both energy companies and transport companies to determine the technological viscosity indicators of composite suspension fuels used as boiler fuel and fuel for marine engines.","PeriodicalId":222237,"journal":{"name":"Power engineering: research, equipment, technology","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132043806","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":"Stationary thermal-gas-dynamics of flows in the cylinder and exhaust system of a piston engine","authors":"L. Plotnikov, V. Shurupov, V. Slednev, D. Davydov, D. Krasilnikov","doi":"10.30724/1998-9903-2023-25-1-130-142","DOIUrl":"https://doi.org/10.30724/1998-9903-2023-25-1-130-142","url":null,"abstract":"THE PURPOSE. To evaluate the influence of the exhaust manifold design on gas dynamics and heat transfer of stationary, turbulent gas flows in the cylinder and the exhaust system of a reciprocating internal combustion engine for different boundary conditions based on physical and mathematical modeling.METHODS. The study of gas dynamics and heat transfer of flows was carried out using the CFD approach in specialized Russian-made software. The simulation was performed for a pressure drop from 0.15 to 40 kPa (the flow velocity at the outlet of the system was 10-130 m/s). The k-e turbulence model was used for modeling. The computational grid consisted of 610,000 cells. The design change consisted in the use of profiled channels with cross sections in the form of a circle (diameter 30 mm), a square (side 30 mm) and a triangle (side 52 mm).RESULTS. The article describes the mathematical model, the studied geometry of the exhaust system and the analysis of the obtained data. The velocity field, isolines of equal velocities, and tangential velocity vectors were chosen as the gas-dynamic characteristics of the flow. The gas dynamics in the longitudinal section of the exhaust system and the valve, as well as the visualization of the flow structure in 4 control sections along the length of the exhaust system, were analyzed. The heat transfer coefficient in the exhaust system was used to evaluate the heat transfer characteristics of the flow. Qualitative and quantitative differences in gas dynamics and heat transfer processes are shown.CONCLUSION. It has been established that there are common gas-dynamic effects during the flow of gas in different elements of the exhaust system. The evolution of the flow structure along the length of the exhaust system is shown based on the change in the velocity field, isolines of equal velocities, and tangential velocity vectors. The vortex structures formed in the valve assembly and the corners of the profiled channels are revealed. It has been established that the use of profiled channels in the exhaust system leads to a decrease in the heat transfer coefficient by 5 to 12%.","PeriodicalId":222237,"journal":{"name":"Power engineering: research, equipment, technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130286349","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":"Review of modern ceramic cellular materials and composites used in heat engineering","authors":"O. Soloveva, S. Solovev, R. Shakurova","doi":"10.30724/1998-9903-2023-25-1-82-104","DOIUrl":"https://doi.org/10.30724/1998-9903-2023-25-1-82-104","url":null,"abstract":"THE PURPOSE. Cellular ceramic materials and composites have found application in many industries: energy, chemical industry, construction, aerospace. Due to their high thermomechanical properties, resistance to high temperatures and low density, cellular ceramic materials are widely used as heat exchangers for heat recovery from exhaust gases of gas turbine engines, combined-cycle plants, industrial furnaces, etc. The purpose of this work is to review modern cellular ceramic materials and composites used in heat engineering and having different structure, properties and chemical composition.METHODS. We have carried out a broad review of the literature on ceramic cellular materials and composites. We studied both domestic and foreign literature.RESULTS. The analysis of cellular ceramic materials with a regular (lattices) and random (foam) structure has been carried out. The main factors influencing the properties of ceramic foams and lattices are analyzed. Also, the main methods for the production of ceramic materials were studied, their advantages and disadvantages were revealed. A review of modern composite materials based on a ceramic matrix reinforced with carbon nanotubes, graphene nanoplates, and carbon fibers has been carried out.CONCLUSION. The properties of ceramic cellular materials, as well as their areas of application, depend on the production methods and the structure of the material. Open-cell foams are used as filters, heat exchangers, while closed-cell foams are used as thermal insulation. Applications for ceramic lattices are limited by the precision, resolution, and size of 3D printing. Thus, the improvement of additive manufacturing technologies will improve the characteristics of ceramic gratings and expand their areas of application.","PeriodicalId":222237,"journal":{"name":"Power engineering: research, equipment, technology","volume":"334 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124703796","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 thermodynamic parameters on the capacity of an air separation unit in the Allam cycle","authors":"P. Shchinnikov, E. M. Korepanova","doi":"10.30724/1998-9903-2023-25-1-74-81","DOIUrl":"https://doi.org/10.30724/1998-9903-2023-25-1-74-81","url":null,"abstract":"The PURPOSE of the work is to establish the relationship between the thermodynamic parameters of the Allam cycle and the capacity of the air separation unit. The air separation plant is a consumer of electricity. To solve the problem, a calculation method is developed and functional dependencies are revealed.METHODS. A research methodology is presented that provides a connection between the thermodynamic parameters of the Allam cycle and its efficiency and fuel consumption, which, in turn, affect the capacity of an air separation plant designed to produce oxygen. The method assumes that the provision of oxygen combustion of methane occurs at their stoichiometric ratio. The method establishes a connection between the thermal efficiency of the cycle and the parameters of the working fluid. Formulas are presented for determining the consumption of standard fuel for the installation, the efficiency of electricity generation and the electric power of the oxygen preparation plant. When obtaining the final result, the factor of influence of the internal relative efficiency of the CO2 turbine is taken into account.RESULTS. The article shows that in the implementation of the Allam cycle based on carbon dioxide by burning methane in oxygen, an oxygen production unit plays a significant role. This is an energy-consuming equipment for own needs. Quantitative estimates have been made and it has been shown how the initial parameters of the thermodynamic cycle affect the capacity of the air separation unit, in which oxygen is produced. The article shows that its capacity can be provided at the level of 20% of the capacity of the power unit.","PeriodicalId":222237,"journal":{"name":"Power engineering: research, equipment, technology","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117320912","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":"Analysis and study of power consumption of objects in the industrial zone of Adra-Syria","authors":"E. Y. Abdullazyanov, E. Gracheva, A. Alzakkar","doi":"10.30724/1998-9903-2023-25-1-118-129","DOIUrl":"https://doi.org/10.30724/1998-9903-2023-25-1-118-129","url":null,"abstract":"Industrial cities in Syria help the state in developing factories and strengthening the main industries, as they provide the right infrastructure for these industries and provide them with advantages that may not be available abroad. The article explores one of these industrial areas in the city of Adra-Syria.PURPUSE. Conduct a study of the design power of loads of residential electrical consumers and compare with the experimental power consumption in the city of Adra.METHODS. Methods for processing statistical data and methods for determining the parameters of loads and graphs of loads of electrical consumers at the facilities of Adra are used.RESULTS. The data on the parameters of the load curves of the electric consumers of the objects of Adra were determined: The average value of the total load power (Saver), the maximum value of the total load power (Smax), the effective value (Seffective), the standard deviation of the total load power (σSng), the value of the load variation (γSng). The data of the load schedule fill factor, the correlation coefficient (Rkj) was calculated and analyzed, and the values of the statistical indicators of the total schedules (Stot) of the electrical consumers of the Kabun-1 substation in Adra, the statistical data of the total apparent power of the electrical consumers of the transformers of the 33/11 kV substation were obtained. \"Kabun-1\", the values of correlation coefficients of loads of industrial electrical consumers, the values of the total power of the load of electrical consumers of the new sector of Adra.CONCLUSION. As a result of the studies carried out, the possibility of effective implementation of measures to regulate the maximum total power of the loads of the main electrical consumers in the city of Adra has been shown.","PeriodicalId":222237,"journal":{"name":"Power engineering: research, equipment, technology","volume":"124 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116330923","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}