Pub Date : 2020-01-01DOI: 10.21272/jnep.12(2).02021
Nupur P. Vora, Priyank V. Kumar, S. Vyas, N. K. Bhatt, P. R. Vyas, V. Gohel
The experimental and theoretical studies of various properties of transition metals alloys are important in the material science research. Inspired by such fact, in the present communication we have carried out theoretical studies of lattice dynamics and dynamical elastic constants of Rh0.6Pd0.4 and Rh0.2Pd0.8 using transition metal pseudopotential. The form of the pseudopotential used in the present calculation is directly derived from generalized pseudopotential theory (GPT) and no phenomenology was used to construct pseudopotential in real space. The pseudopotential was found to be successful for the study of static, dynamic and transport properties of many transition metals. In absence of any experimental and theoretical studies first time we are presenting theoretical results of phonon dispersion for both the alloys which may be considered as prediction. Due to unavailability of experimental results, presently computed elastic constants are comparable with those studied recently by using Exact Muffin-Tin Orbitals method within the Perdew-Burke-Ernzerhof exchange-correlation approximation. Encouraged by present approach, we would like to extend it further for the remaining binary alloys of transition metals alloys.
{"title":"Theoretical Investigations of Lattice Dynamics and Dynamical Elastic Constants of Rh0.6Pd0.4 and Rh0.2Pd0.8 Binary Alloys Using Transition Metal Pseudopotential","authors":"Nupur P. Vora, Priyank V. Kumar, S. Vyas, N. K. Bhatt, P. R. Vyas, V. Gohel","doi":"10.21272/jnep.12(2).02021","DOIUrl":"https://doi.org/10.21272/jnep.12(2).02021","url":null,"abstract":"The experimental and theoretical studies of various properties of transition metals alloys are important in the material science research. Inspired by such fact, in the present communication we have carried out theoretical studies of lattice dynamics and dynamical elastic constants of Rh0.6Pd0.4 and Rh0.2Pd0.8 using transition metal pseudopotential. The form of the pseudopotential used in the present calculation is directly derived from generalized pseudopotential theory (GPT) and no phenomenology was used to construct pseudopotential in real space. The pseudopotential was found to be successful for the study of static, dynamic and transport properties of many transition metals. In absence of any experimental and theoretical studies first time we are presenting theoretical results of phonon dispersion for both the alloys which may be considered as prediction. Due to unavailability of experimental results, presently computed elastic constants are comparable with those studied recently by using Exact Muffin-Tin Orbitals method within the Perdew-Burke-Ernzerhof exchange-correlation approximation. Encouraged by present approach, we would like to extend it further for the remaining binary alloys of transition metals alloys.","PeriodicalId":16514,"journal":{"name":"Journal of Nano- and Electronic Physics","volume":"4 4 1","pages":"02021-1-02021-3"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90235797","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}
Pub Date : 2020-01-01DOI: 10.21272/jnep.12(4).04017
M. Veerabhadrayya, R. Kumari, G. Nagaraju, Udayabhanu Udayabhanu, Y. T. Ravikiran, B. Chethan, Tumakuru India. Commerce
{"title":"Structural, Optical and Electrical Properties of Ce Doped SnO2 Nanoparticles Prepared by Surfactant Assisted Gel Combustion Method","authors":"M. Veerabhadrayya, R. Kumari, G. Nagaraju, Udayabhanu Udayabhanu, Y. T. Ravikiran, B. Chethan, Tumakuru India. Commerce","doi":"10.21272/jnep.12(4).04017","DOIUrl":"https://doi.org/10.21272/jnep.12(4).04017","url":null,"abstract":"","PeriodicalId":16514,"journal":{"name":"Journal of Nano- and Electronic Physics","volume":"32 4 1","pages":"04017-1-04017-6"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83643118","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}
Pub Date : 2020-01-01DOI: 10.21272/jnep.12(5).05034
Parisa Shirvani, H. Shirzadfar
Telemedicine is a form of remote medical practice using information and communication technologies which facilitates distance mediation between the patient and the medical staff. In rural or remote areas where many of the specialized medical services required by the community do not reach, telemedicine can be a viable and reliable alternative to facilitate access to these services as the use of telemedicine technology leads to higher levels of health care and treatment. As in telemedicine systems antennas have an important role, we focus on the optimal design of used antennas to achieve better results. The role of an antenna is to convert the electrical energy of a signal into electromagnetic energy, or conversely to convert electromagnetic energy into electrical energy. A transmitting antenna is a device that transmits energy between an emitter and the free space where this energy will propagate. The rapid development of wireless communication systems has led to numerous improvements in telecommunication antennas and systems to meet the needs of telemedicine applications. The microstrip patch antenna is a planar antenna that has received a lot of attention due to its flat geometry. These types of antennas are very popular among designers and are used in many applications. This paper presents an improved patch antenna and array antenna with microstrip feed line using three kinds of metamaterial (MTM) structures that can be very useful in telemedicine systems. A metamaterial is an artificial composite material with unnatural electromagnetic properties. Different structures are considered and analyzed to reach a good performance antenna. Proposed structures increase the gain of antennas which are used in telemedicine systems. The structures of the mushroom-like electromagnetic band gap (EBG), the one layer and two-layer woodpile EBG in straight and curved forms have been discussed and analyzed. The operating frequency is 2.45 GHz for telemedicine applications. The simulation process has been done through High Frequency Structure Simulator (HFSS) software and the results are compared.
{"title":"Gain Enhancement of Microstrip Patch Antenna and Array Antenna Using Different Metamaterial Structures for Telemedicine Applications","authors":"Parisa Shirvani, H. Shirzadfar","doi":"10.21272/jnep.12(5).05034","DOIUrl":"https://doi.org/10.21272/jnep.12(5).05034","url":null,"abstract":"Telemedicine is a form of remote medical practice using information and communication technologies which facilitates distance mediation between the patient and the medical staff. In rural or remote areas where many of the specialized medical services required by the community do not reach, telemedicine can be a viable and reliable alternative to facilitate access to these services as the use of telemedicine technology leads to higher levels of health care and treatment. As in telemedicine systems antennas have an important role, we focus on the optimal design of used antennas to achieve better results. The role of an antenna is to convert the electrical energy of a signal into electromagnetic energy, or conversely to convert electromagnetic energy into electrical energy. A transmitting antenna is a device that transmits energy between an emitter and the free space where this energy will propagate. The rapid development of wireless communication systems has led to numerous improvements in telecommunication antennas and systems to meet the needs of telemedicine applications. The microstrip patch antenna is a planar antenna that has received a lot of attention due to its flat geometry. These types of antennas are very popular among designers and are used in many applications. This paper presents an improved patch antenna and array antenna with microstrip feed line using three kinds of metamaterial (MTM) structures that can be very useful in telemedicine systems. A metamaterial is an artificial composite material with unnatural electromagnetic properties. Different structures are considered and analyzed to reach a good performance antenna. Proposed structures increase the gain of antennas which are used in telemedicine systems. The structures of the mushroom-like electromagnetic band gap (EBG), the one layer and two-layer woodpile EBG in straight and curved forms have been discussed and analyzed. The operating frequency is 2.45 GHz for telemedicine applications. The simulation process has been done through High Frequency Structure Simulator (HFSS) software and the results are compared.","PeriodicalId":16514,"journal":{"name":"Journal of Nano- and Electronic Physics","volume":"30 1","pages":"05034-1-05034-5"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86172400","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}
Pub Date : 2020-01-01DOI: 10.21272/jnep.12(2).02019
P. Suthar, P. Gajjar
{"title":"Theoretical Study of Structural and Dynamical Properties of Liquid Ag74Ge26 Alloys Using Pseudopotential Method","authors":"P. Suthar, P. Gajjar","doi":"10.21272/jnep.12(2).02019","DOIUrl":"https://doi.org/10.21272/jnep.12(2).02019","url":null,"abstract":"","PeriodicalId":16514,"journal":{"name":"Journal of Nano- and Electronic Physics","volume":"26 1","pages":"02019-1-02019-3"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86189385","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}
Pub Date : 2020-01-01DOI: 10.21272/jnep.12(1).01013
V. Mandzyuk, I. Mironyuk, Y. Kulyk, N. A. Bezruka, Lviv Ukraine Mefodiy St.
{"title":"Structural-morphological and Conductive Properties of С-Al2O3 Composite Materials","authors":"V. Mandzyuk, I. Mironyuk, Y. Kulyk, N. A. Bezruka, Lviv Ukraine Mefodiy St.","doi":"10.21272/jnep.12(1).01013","DOIUrl":"https://doi.org/10.21272/jnep.12(1).01013","url":null,"abstract":"","PeriodicalId":16514,"journal":{"name":"Journal of Nano- and Electronic Physics","volume":"61 1","pages":"01013-1-01013-6"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86636504","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}
Pub Date : 2020-01-01DOI: 10.21272/jnep.12(1).01017
C. Sheng, Y. M. Alrababah
In this work, room-temperature treated CdS nanoparticles were prepared in KOH solution via precipitation at different pH values by varying the ammonium nitrate (NH4NO3) concentration. The crystallite phase and size, surface morphology and infrared frequencies of functional groups were characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy, respectively. The SEM images show that the CdS nanoparticles are spherical in shape. Meanwhile, the FTIR result reveals that a broad band occurred in the range of 400-700 cm − 1 could be attributed to the molecular bonding structure of CdS. The XRD patterns exhibit four well-resolved crystalline peaks that represents the diffraction planes of a cubic CdS phase. Nevertheless, a minor decrement in the intensity for both infrared and crystalline bands denotes a slight reduction in structure crystallinity and further indicates that a higher purity of finer CdS nanoparticles is obtained as the pH value decreases. Also, the diffraction peak becomes slightly widen that implies a decrease in the mean crystallite size as validated by Debye-Scherrer method. Owing to their unique nanostructural and morphological features, the CdS nanoparticles obtained in this study have potential applications in photonic devices, optoelectronics, photocatalysis and solar cells.
{"title":"The Role of pH on Infrared Spectral, Structural and Morphological Properties of Room-temperature Precipitated CdS Nanoparticles","authors":"C. Sheng, Y. M. Alrababah","doi":"10.21272/jnep.12(1).01017","DOIUrl":"https://doi.org/10.21272/jnep.12(1).01017","url":null,"abstract":"In this work, room-temperature treated CdS nanoparticles were prepared in KOH solution via precipitation at different pH values by varying the ammonium nitrate (NH4NO3) concentration. The crystallite phase and size, surface morphology and infrared frequencies of functional groups were characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy, respectively. The SEM images show that the CdS nanoparticles are spherical in shape. Meanwhile, the FTIR result reveals that a broad band occurred in the range of 400-700 cm − 1 could be attributed to the molecular bonding structure of CdS. The XRD patterns exhibit four well-resolved crystalline peaks that represents the diffraction planes of a cubic CdS phase. Nevertheless, a minor decrement in the intensity for both infrared and crystalline bands denotes a slight reduction in structure crystallinity and further indicates that a higher purity of finer CdS nanoparticles is obtained as the pH value decreases. Also, the diffraction peak becomes slightly widen that implies a decrease in the mean crystallite size as validated by Debye-Scherrer method. Owing to their unique nanostructural and morphological features, the CdS nanoparticles obtained in this study have potential applications in photonic devices, optoelectronics, photocatalysis and solar cells.","PeriodicalId":16514,"journal":{"name":"Journal of Nano- and Electronic Physics","volume":"11 1","pages":"01017-1-01017-4"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90501881","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}
Pub Date : 2020-01-01DOI: 10.21272/jnep.12(2).02015
S. J. Patel, A. Jariwala, C. Panchal, V. Kheraj
In this paper, we report a simple method to extract thickness and refractive index of thin-film from experimentally measured reflectivity spectra using teaching-learning based optimization (TLBO) algorithm. The algorithm finds thickness and refractive index by fitting an experimentally measured reflectivity spectra with theoretically ones generated by transfer matrix approach. The value of refractive index as a function of wavelength is determined by considering sellmeier dispersion relation. The algorithm is implemented by means of an interactive numerical simulation using LabVIEW as a programming tool. To check the effectiveness of the self-developed program, it is tested on different thin-film samples prepared from some commonly used optical materials such as MgF2, Al2O3 and SiO2 using electron beam evaporation technique. The values of thicknesses and refractive index spectra for different thin-film samples obtained by TLBO algorithm are verified using standard spectroscopic ellipsometry measurements. It is found that there is an excellent agreement between the results obtained by the TLBO algorithm and those by ellipsometry. It is also demonstrated that a simple reflectivity measurements give the valuable information about the thickness and dispersive refractive index over a range of wavelengths, which are obtained by our self-developed simulation program based on TLBO algorithm.
{"title":"Determination of Thickness and Optical Parameters of Thin Films from Reflectivity Spectra Using Teaching-Learning Based Optimization Algorithm","authors":"S. J. Patel, A. Jariwala, C. Panchal, V. Kheraj","doi":"10.21272/jnep.12(2).02015","DOIUrl":"https://doi.org/10.21272/jnep.12(2).02015","url":null,"abstract":"In this paper, we report a simple method to extract thickness and refractive index of thin-film from experimentally measured reflectivity spectra using teaching-learning based optimization (TLBO) algorithm. The algorithm finds thickness and refractive index by fitting an experimentally measured reflectivity spectra with theoretically ones generated by transfer matrix approach. The value of refractive index as a function of wavelength is determined by considering sellmeier dispersion relation. The algorithm is implemented by means of an interactive numerical simulation using LabVIEW as a programming tool. To check the effectiveness of the self-developed program, it is tested on different thin-film samples prepared from some commonly used optical materials such as MgF2, Al2O3 and SiO2 using electron beam evaporation technique. The values of thicknesses and refractive index spectra for different thin-film samples obtained by TLBO algorithm are verified using standard spectroscopic ellipsometry measurements. It is found that there is an excellent agreement between the results obtained by the TLBO algorithm and those by ellipsometry. It is also demonstrated that a simple reflectivity measurements give the valuable information about the thickness and dispersive refractive index over a range of wavelengths, which are obtained by our self-developed simulation program based on TLBO algorithm.","PeriodicalId":16514,"journal":{"name":"Journal of Nano- and Electronic Physics","volume":"46 1","pages":"02015-1-02015-6"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80737887","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}
Pub Date : 2020-01-01DOI: 10.21272/jnep.12(3).03030
P. Kolkovskyi, B. Rachiy, M. I. Kolkovskyi, B. Ostafiychuk, I. Yaremiy, V. Kotsyubynsky, R. V. Ilnitsky
{"title":"Synthesis and Electrochemical Properties of Mesoporous α-MnO2 for Supercapacitor Applications","authors":"P. Kolkovskyi, B. Rachiy, M. I. Kolkovskyi, B. Ostafiychuk, I. Yaremiy, V. Kotsyubynsky, R. V. Ilnitsky","doi":"10.21272/jnep.12(3).03030","DOIUrl":"https://doi.org/10.21272/jnep.12(3).03030","url":null,"abstract":"","PeriodicalId":16514,"journal":{"name":"Journal of Nano- and Electronic Physics","volume":"529 1","pages":"03030-1-03030-4"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79638889","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}
Pub Date : 2020-01-01DOI: 10.21272/jnep.12(5).05022
K. Bendjebbar, D. Rached, W. Rahal, S. Bahlouli
The silicon HIT (heterojunction with intrinsic thin layer) solar cell has great potential to improve photovoltaic efficiency and reduce costs because of the low temperature deposition technology of hydrogenated amorphous silicon a-Si:H combined with the high stable efficiency of crystalline silicon c-Si. To gain insight into the general functioning of the HIT solar cell, we have studied in this article the semiconductor-metal junction at the back contact of HIT p-type c-Si solar cell: (indium tin oxide (ITO)/hydrogenated n-doped amorphous silicon (n-a-Si:H)/hydrogenated intrinsic polymorphous silicon (i-pm-Si:H)/p-doped crystalline silicon (p-c-Si)/aluminum (Al)). Using computer modeling, we have found that unlike the junction on ITO/ n-a-Si:H on the front HIT solar cells which does not depend on the front contact barrier height b0, an increase in the back contact barrier height bL leads to an upward band bending in the valence band in this type of cell which eliminates the barrier for holes and makes more photogenerated holes able to pass from the active layer (p-doped crystalline silicon p-c-Si) to the metal (aluminium). The increase in the electric field by changing the surface band bending at the junction p-c-Si/Al causes an increase in VOC which leads to an increase in the solar cell efficiency from 17.21 % to 17.38 %. Choosing metal with high work function like palladium, chrome or ruthenium, could be the best choice as a back contact for this type of solar cell.
{"title":"Simulation Study of Metal-semiconductor Back Contact p-c-Si/Al on Silicon Heterojunction Solar Cells","authors":"K. Bendjebbar, D. Rached, W. Rahal, S. Bahlouli","doi":"10.21272/jnep.12(5).05022","DOIUrl":"https://doi.org/10.21272/jnep.12(5).05022","url":null,"abstract":"The silicon HIT (heterojunction with intrinsic thin layer) solar cell has great potential to improve photovoltaic efficiency and reduce costs because of the low temperature deposition technology of hydrogenated amorphous silicon a-Si:H combined with the high stable efficiency of crystalline silicon c-Si. To gain insight into the general functioning of the HIT solar cell, we have studied in this article the semiconductor-metal junction at the back contact of HIT p-type c-Si solar cell: (indium tin oxide (ITO)/hydrogenated n-doped amorphous silicon (n-a-Si:H)/hydrogenated intrinsic polymorphous silicon (i-pm-Si:H)/p-doped crystalline silicon (p-c-Si)/aluminum (Al)). Using computer modeling, we have found that unlike the junction on ITO/ n-a-Si:H on the front HIT solar cells which does not depend on the front contact barrier height b0, an increase in the back contact barrier height bL leads to an upward band bending in the valence band in this type of cell which eliminates the barrier for holes and makes more photogenerated holes able to pass from the active layer (p-doped crystalline silicon p-c-Si) to the metal (aluminium). The increase in the electric field by changing the surface band bending at the junction p-c-Si/Al causes an increase in VOC which leads to an increase in the solar cell efficiency from 17.21 % to 17.38 %. Choosing metal with high work function like palladium, chrome or ruthenium, could be the best choice as a back contact for this type of solar cell.","PeriodicalId":16514,"journal":{"name":"Journal of Nano- and Electronic Physics","volume":"78 4 1","pages":"05022-1-05022-4"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79643765","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}
Pub Date : 2020-01-01DOI: 10.21272/jnep.12(3).03033
N. Inshyna, I. Chorna, L. Primova, L. Hrebenyk, Y. Khyzhnia
{"title":"Biosensors: Design, Classification and Application","authors":"N. Inshyna, I. Chorna, L. Primova, L. Hrebenyk, Y. Khyzhnia","doi":"10.21272/jnep.12(3).03033","DOIUrl":"https://doi.org/10.21272/jnep.12(3).03033","url":null,"abstract":"","PeriodicalId":16514,"journal":{"name":"Journal of Nano- and Electronic Physics","volume":"61 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84573950","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}
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