Pub Date : 2024-03-20DOI: 10.1134/s1064226923150159
L. Y. Fetisov, D. V. Savelev, F. A. Fedulov, D. V. Chashin, Y. K. Fetisov
Abstract
A resonant voltage frequency doubler using the nonlinear magnetoelectric effect in planar heterostructure containing a piezoelectric langatate single crystal placed between two layers of amorphous ferromagnetic Metglas alloy was fabricated and studied. The frequency doubling occurred due to the nonlinear dependence of the Metglas magnetostriction on the magnetic field. A nonlinear magnetoelectric coefficient of 7.1 V/(cm Oe2) was obtained at acoustic resonance frequency of the structure due to high acoustic quality factor of ~2820. The power conversion coefficient of the doubler reached ~1% at optimal bias magnetic field of 2 Oe and matched load resistance of 0.8 kΩ.
{"title":"Frequency Doubler Based on Nonlinear Magnetoelectric Effect in a Planar Metglas/Langatate/Metglas Heterostructure","authors":"L. Y. Fetisov, D. V. Savelev, F. A. Fedulov, D. V. Chashin, Y. K. Fetisov","doi":"10.1134/s1064226923150159","DOIUrl":"https://doi.org/10.1134/s1064226923150159","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A resonant voltage frequency doubler using the nonlinear magnetoelectric effect in planar heterostructure containing a piezoelectric langatate single crystal placed between two layers of amorphous ferromagnetic Metglas alloy was fabricated and studied. The frequency doubling occurred due to the nonlinear dependence of the Metglas magnetostriction on the magnetic field. A nonlinear magnetoelectric coefficient of 7.1 V/(cm Oe<sup>2</sup>) was obtained at acoustic resonance frequency of the structure due to high acoustic quality factor of ~2820. The power conversion coefficient of the doubler reached ~1% at optimal bias magnetic field of 2 Oe and matched load resistance of 0.8 kΩ.</p>","PeriodicalId":50229,"journal":{"name":"Journal of Communications Technology and Electronics","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140166078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-20DOI: 10.1134/s1064226923150056
M. S. Domnina, A. S. Kryukovsky, D. V. Rastyagaev
Abstract
Methods for calculating the special function of wave catastrophe B4 and its first derivatives, which describe edge focusing of the caustic-tip type with an edge, are studied. The caustic and ray structures of this singularity are constructed. The characteristic amplitude–phase sections of the special function and its derivatives are calculated. The method of rotation of the integration contour and the method of ordinary differential equations are considered and compared both in terms of accuracy and speed. It is shown that the method of ordinary differential equations works stably in the region of negative values of the first two parameters of the special function, and the method of rotation of the integration contour exhibits stability in the region of positive values. Thus, the approaches are complementary. However, the calculation time for the method of ordinary differential equations is an order of magnitude less than the time for the method of rotation of the integration contour.
{"title":"Mathematical Modeling of the Wave-Field Structure in the Vicinity of Edge Catastrophe B4","authors":"M. S. Domnina, A. S. Kryukovsky, D. V. Rastyagaev","doi":"10.1134/s1064226923150056","DOIUrl":"https://doi.org/10.1134/s1064226923150056","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Methods for calculating the special function of wave catastrophe B<sub>4</sub> and its first derivatives, which describe edge focusing of the caustic-tip type with an edge, are studied. The caustic and ray structures of this singularity are constructed. The characteristic amplitude–phase sections of the special function and its derivatives are calculated. The method of rotation of the integration contour and the method of ordinary differential equations are considered and compared both in terms of accuracy and speed. It is shown that the method of ordinary differential equations works stably in the region of negative values of the first two parameters of the special function, and the method of rotation of the integration contour exhibits stability in the region of positive values. Thus, the approaches are complementary. However, the calculation time for the method of ordinary differential equations is an order of magnitude less than the time for the method of rotation of the integration contour.</p>","PeriodicalId":50229,"journal":{"name":"Journal of Communications Technology and Electronics","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140881779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-20DOI: 10.1134/s1064226923150032
E. A. Barabanova, V. M. Vishnevsky, K. A. Vytovtov, O. V. Semenova
Abstract
This paper presents the analytical approach to the study of non-stationary characteristics of information-measuring system operating in the event of faults. Analysis of the performance of signal processing devices in this mode of operation is an important problem and it is of great interest for modern instrumentation. The main characteristics of the performance of information-measuring systems under periodic faults are obtained, such as the probability of distortion and loss of signals, the time of the transition mode. The paper also presents numerical calculations of the characteristics of the information-measuring system with three different types of devices.
{"title":"Methods of Analysis of Information-Measuring System Performance under Fault Conditions","authors":"E. A. Barabanova, V. M. Vishnevsky, K. A. Vytovtov, O. V. Semenova","doi":"10.1134/s1064226923150032","DOIUrl":"https://doi.org/10.1134/s1064226923150032","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">\u0000<b>Abstract</b>\u0000</h3><p>This paper presents the analytical approach to the study of non-stationary characteristics of information-measuring system operating in the event of faults. Analysis of the performance of signal processing devices in this mode of operation is an important problem and it is of great interest for modern instrumentation. The main characteristics of the performance of information-measuring systems under periodic faults are obtained, such as the probability of distortion and loss of signals, the time of the transition mode. The paper also presents numerical calculations of the characteristics of the information-measuring system with three different types of devices.</p>","PeriodicalId":50229,"journal":{"name":"Journal of Communications Technology and Electronics","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140881890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-20DOI: 10.1134/s1064226923150020
E. A. Barabanova, K. A. Vytovtov, T. Ya. Gladkikh, A. N. Migachev
Abstract
A new simple approach to studying pollution of water bodies with petroleum products: crude oil, boat oil, and diesel fuel, using multispectral cameras mounted on quadrocopters is presented. A laboratory experiment was carried out and the reflection spectra of sunlight from various types of pollution were analyzed. Expressions for the spectral brightness coefficient index are found. Field tests were carried out and the resulting relationships were verified for real conditions. The results of field tests showed that the proposed approach makes it possible to determine pollution in water bodies with sizes starting from 10 cm.
{"title":"Environmental Monitoring of Water Surface Pollution in the Visible Range by Using UAVs","authors":"E. A. Barabanova, K. A. Vytovtov, T. Ya. Gladkikh, A. N. Migachev","doi":"10.1134/s1064226923150020","DOIUrl":"https://doi.org/10.1134/s1064226923150020","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A new simple approach to studying pollution of water bodies with petroleum products: crude oil, boat oil, and diesel fuel, using multispectral cameras mounted on quadrocopters is presented. A laboratory experiment was carried out and the reflection spectra of sunlight from various types of pollution were analyzed. Expressions for the spectral brightness coefficient index are found. Field tests were carried out and the resulting relationships were verified for real conditions. The results of field tests showed that the proposed approach makes it possible to determine pollution in water bodies with sizes starting from 10 cm.</p>","PeriodicalId":50229,"journal":{"name":"Journal of Communications Technology and Electronics","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140165698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-20DOI: 10.1134/s1064226923150123
E. M. Volodina, A. I. Lyashenko
Abstract
The results of determination of the peak power of monopulses of YAG:Nd3+ laser emission by two methods are presented. It is shown that the most reliable data can be obtained by the procedure from GOST and by the often used method when recording the time form of the monopulse of radiation using an FK-15 coaxial photocell. An often used technique using the measured value of the monopulse duration by the level of 0.5 of the amplitude value, when recording the time shape using an LFD-2 avalanche photodiode overestimates the value of the peak power of the monopulse compared to a reliable one by 12%.
{"title":"Determination of the Peak Power of Monopulses of YAG:Nd3+ Laser Emission","authors":"E. M. Volodina, A. I. Lyashenko","doi":"10.1134/s1064226923150123","DOIUrl":"https://doi.org/10.1134/s1064226923150123","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The results of determination of the peak power of monopulses of YAG:Nd<sup>3+</sup> laser emission by two methods are presented. It is shown that the most reliable data can be obtained by the procedure from GOST and by the often used method when recording the time form of the monopulse of radiation using an FK-15 coaxial photocell. An often used technique using the measured value of the monopulse duration by the level of 0.5 of the amplitude value, when recording the time shape using an LFD-2 avalanche photodiode overestimates the value of the peak power of the monopulse compared to a reliable one by 12%.</p>","PeriodicalId":50229,"journal":{"name":"Journal of Communications Technology and Electronics","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140166098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-20DOI: 10.1134/s1064226923150081
V. F. Kravchenko, A. A. Kurayev, V. V. Matveyenko
Abstract
The article formulates equations for longitudinally irregular waveguide excitation by three-dimensionally phased electron flows taking into account the finite wall conductivity. A.G. Sveshnikov’s method based on using non-orthogonal coordinates for Maxwell’s equations to formulate the excitation equations, which makes it possible to transpose the irregular boundary of the electrodynamic structure to a regular one. Then, Galerkin’s projection method is used for the transformed regular region with a priori known complete system of vector basis functions for this region. A special approach allows one to solve the difficulty arising due to the boundary conditions for the vector basis functions and the solution on the waveguide surface in the case of finite conductivity. As a result, the original three-dimensional boundary value problem is derived to a one-dimensional (two-point) boundary value problem for the amplitudes of normal coupled waves of the electrodynamic structure. This problem formulates an ordinary differential equation (ODE) system with boundary conditions of the third kind on the first and final sections of the waveguide. The excitation equations, together with the equations of electron motion, form a self-consistent mathematical model for calculating and optimizing high-power electronic devices using irregular waveguides: relativistic traveling wave tubes (TWTs), backward wave oscillators (BWOs), klynotrons, gyro-TWTs, gyro-BWOs, and gyrotons.
{"title":"Excitation Equations for Irregular Waveguides Taking into Account the Finite Wall Conductivity and Their Application for Ultrahigh-Power Microwave Problems. Part 1","authors":"V. F. Kravchenko, A. A. Kurayev, V. V. Matveyenko","doi":"10.1134/s1064226923150081","DOIUrl":"https://doi.org/10.1134/s1064226923150081","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The article formulates equations for longitudinally irregular waveguide excitation by three-dimensionally phased electron flows taking into account the finite wall conductivity. A.G. Sveshnikov’s method based on using non-orthogonal coordinates for Maxwell’s equations to formulate the excitation equations, which makes it possible to transpose the irregular boundary of the electrodynamic structure to a regular one. Then, Galerkin’s projection method is used for the transformed regular region with a priori known complete system of vector basis functions for this region. A special approach allows one to solve the difficulty arising due to the boundary conditions for the vector basis functions and the solution on the waveguide surface in the case of finite conductivity. As a result, the original three-dimensional boundary value problem is derived to a one-dimensional (two-point) boundary value problem for the amplitudes of normal coupled waves of the electrodynamic structure. This problem formulates an ordinary differential equation (ODE) system with boundary conditions of the third kind on the first and final sections of the waveguide. The excitation equations, together with the equations of electron motion, form a self-consistent mathematical model for calculating and optimizing high-power electronic devices using irregular waveguides: relativistic traveling wave tubes (TWTs), backward wave oscillators (BWOs), klynotrons, gyro-TWTs, gyro-BWOs, and gyrotons.</p>","PeriodicalId":50229,"journal":{"name":"Journal of Communications Technology and Electronics","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140882028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-20DOI: 10.1134/s1064226923150044
K. A. Budunova, V. F. Kravchenko
Abstract
Review of both classical and rarely used methods for synthesis of digital and analogue frequency-selective filters is presented. For continuous filters, different transfer functions are considered. For digital filters, a description of various optimization methods is given. Parametric families of sampling mappings are discussed. Methods for filter synthesis using atomic functions are described.
{"title":"Mathematical Methods for the Synthesis of Frequency-Selective Filters","authors":"K. A. Budunova, V. F. Kravchenko","doi":"10.1134/s1064226923150044","DOIUrl":"https://doi.org/10.1134/s1064226923150044","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Review of both classical and rarely used methods for synthesis of digital and analogue frequency-selective filters is presented. For continuous filters, different transfer functions are considered. For digital filters, a description of various optimization methods is given. Parametric families of sampling mappings are discussed. Methods for filter synthesis using atomic functions are described.</p>","PeriodicalId":50229,"journal":{"name":"Journal of Communications Technology and Electronics","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140881778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-20DOI: 10.1134/s1064226923120045
M. G. Bakulin, T. B. K. Ben Rejeb, V. B. Kreindelin, D. Yu. Pankratov, A. E. Smirnov
Abstract
An analytical method is proposed for describing signal constellations in the form of a functional dependence on a multidimensional vector of binary variables. A transformation is given that allows one to move from the traditional tabular description of modulated signals to the proposed analytical description. The method makes it possible to more compactly describe signals modulated by digital information, especially with a high modulation order, and to identify some patterns in known modulation methods and extend them to higher order modulations. An analytical description of signal constellations makes it possible to synthesize new demodulation algorithms for various communication systems. Simple examples show the advantages of the proposed approach over traditional methods based on tabular representation of signals.
{"title":"Binary Representation of Signal Constellations and its Use for Analyzing Modulated Signals","authors":"M. G. Bakulin, T. B. K. Ben Rejeb, V. B. Kreindelin, D. Yu. Pankratov, A. E. Smirnov","doi":"10.1134/s1064226923120045","DOIUrl":"https://doi.org/10.1134/s1064226923120045","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>An analytical method is proposed for describing signal constellations in the form of a functional dependence on a multidimensional vector of binary variables. A transformation is given that allows one to move from the traditional tabular description of modulated signals to the proposed analytical description. The method makes it possible to more compactly describe signals modulated by digital information, especially with a high modulation order, and to identify some patterns in known modulation methods and extend them to higher order modulations. An analytical description of signal constellations makes it possible to synthesize new demodulation algorithms for various communication systems. Simple examples show the advantages of the proposed approach over traditional methods based on tabular representation of signals.</p>","PeriodicalId":50229,"journal":{"name":"Journal of Communications Technology and Electronics","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140172838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-20DOI: 10.1134/s1064226923150135
M. V. Alampiev, E. M. Volodina, V. A. Kukushkin, A. I. Lyashenko
Abstract
The results of measurements of temporal parameters of a Q-switched Nd:YAG laser with an intraresonator optical parametric oscillator and high harmonic and sum frequency cascade generation are presented. Pulse durations by a level of 0.5 and front durations by levels of 0.1–0.9 of monopulses peak power of RGB-laser monopulses in the spectral range from 355 to 1572 nm using an LFD-2A germanium avalanche photodiode and Thorlabs DET08CL/M InGaAs pin-diode with a LECROY (2.5 GHz) digital oscilloscope were measured. The results may be used in air- and sea-LIDARs.
{"title":"Nd:YAG Laser with OPO Monopulse Emission Temporal Parameters","authors":"M. V. Alampiev, E. M. Volodina, V. A. Kukushkin, A. I. Lyashenko","doi":"10.1134/s1064226923150135","DOIUrl":"https://doi.org/10.1134/s1064226923150135","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The results of measurements of temporal parameters of a Q-switched Nd:YAG laser with an intraresonator optical parametric oscillator and high harmonic and sum frequency cascade generation are presented. Pulse durations by a level of 0.5 and front durations by levels of 0.1–0.9 of monopulses peak power of RGB-laser monopulses in the spectral range from 355 to 1572 nm using an LFD-2A germanium avalanche photodiode and Thorlabs DET08CL/M InGaAs pin-diode with a LECROY (2.5 GHz) digital oscilloscope were measured. The results may be used in air- and sea-LIDARs.</p>","PeriodicalId":50229,"journal":{"name":"Journal of Communications Technology and Electronics","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140173071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-20DOI: 10.1134/s1064226923150019
E. A. Barabanova, K. A. Vytovtov
Abstract
In this paper, non-stationary characteristics of signal processing devices of information-measuring systems with dissimilar devices are investigated. For modern instrumentation, it is of interest to study the transient mode of the system that occurs at the moments of turning on and off devices and rebooting the measuring switch. The main characteristics of the information-measuring system in non-stationary mode, such as the probability of signal loss, the transient time, the throughput, and the number of switched signals in the system at time t, and their average values in the transition mode, are obtained. The paper presents numerical calculations of the characteristics of the measuring switch using the example of an information-measuring system with three different types of devices.
摘要 本文研究了具有不同装置的信息测量系统信号处理装置的非稳态特性。对于现代仪器仪表来说，研究在打开和关闭设备以及重新启动测量开关时发生的系统瞬态模式很有意义。本文获得了信息测量系统在非稳态模式下的主要特征，如信号丢失概率、瞬态时间、吞吐量和系统在 t 时刻的切换信号数量，以及它们在过渡模式下的平均值。论文以带有三种不同类型设备的信息测量系统为例，对测量开关的特性进行了数值计算。
{"title":"Investigation of Non-Stationary Characteristics of Signal Switching Devices of Information-Measuring Systems with Dissimilar Devices","authors":"E. A. Barabanova, K. A. Vytovtov","doi":"10.1134/s1064226923150019","DOIUrl":"https://doi.org/10.1134/s1064226923150019","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>In this paper, non-stationary characteristics of signal processing devices of information-measuring systems with dissimilar devices are investigated. For modern instrumentation, it is of interest to study the transient mode of the system that occurs at the moments of turning on and off devices and rebooting the measuring switch. The main characteristics of the information-measuring system in non-stationary mode, such as the probability of signal loss, the transient time, the throughput, and the number of switched signals in the system at time <i>t</i>, and their average values in the transition mode, are obtained. The paper presents numerical calculations of the characteristics of the measuring switch using the example of an information-measuring system with three different types of devices.</p>","PeriodicalId":50229,"journal":{"name":"Journal of Communications Technology and Electronics","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140881885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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