Pub Date : 2023-01-01DOI: 10.21883/ftt.2023.09.56250.166
О. С. Гусева, О. В. Малышкина
In this work, ceramic samples with a structure of the type of tetragonal tungsten bronzes, composition Са0.3Ba0.7Nb2O6 (CBN30) pure and with modifying additives SrTiO3, KTaO3 or LiTaO3 (5 mass %) were studied by the oscillographic method. It is shown that the introduction of modifying additives into CBN30 ceramics leads to an increase in the reversal polarization and to a decrease in dielectric losses, both at room temperature and at high temperatures. The introduction of LiTaO3 impurity into the CBN30 composition leads to the greatest increase in the reversal polarization. In contrast to ceramics based on lead zirconate titanate, which have a perovskite type structure, the introduction of SrTiO3 into CBN30 (having the structure of tetragonal tungsten bronzes) does not significantly improve the ferroelectric properties. It has been found that at temperatures above 100 °C for pure CBN30 ceramics, above 165 °C for CBN30 + 5% SrTiO3 and CBN30 + 5% KTaO3, and above 200 оС for CBN30 + 5% LiTaO3, there is a strong increase in dielectric losses. The contribution of dielectric losses to switching processes makes it impossible to determine the temperature of the ferroelectric phase transition for solid solutions based on CBN30 from the temperature dependences of dielectric hysteresis loops.
{"title":"Процессы переключения в керамике твердых растворов на основе Ca-=SUB=-0.3-=/SUB=-Ba-=SUB=-0.7-=/SUB=-Nb-=SUB=-2-=/SUB=-O-=SUB=-6-=/SUB=-","authors":"О. С. Гусева, О. В. Малышкина","doi":"10.21883/ftt.2023.09.56250.166","DOIUrl":"https://doi.org/10.21883/ftt.2023.09.56250.166","url":null,"abstract":"In this work, ceramic samples with a structure of the type of tetragonal tungsten bronzes, composition Са0.3Ba0.7Nb2O6 (CBN30) pure and with modifying additives SrTiO3, KTaO3 or LiTaO3 (5 mass %) were studied by the oscillographic method. It is shown that the introduction of modifying additives into CBN30 ceramics leads to an increase in the reversal polarization and to a decrease in dielectric losses, both at room temperature and at high temperatures. The introduction of LiTaO3 impurity into the CBN30 composition leads to the greatest increase in the reversal polarization. In contrast to ceramics based on lead zirconate titanate, which have a perovskite type structure, the introduction of SrTiO3 into CBN30 (having the structure of tetragonal tungsten bronzes) does not significantly improve the ferroelectric properties. It has been found that at temperatures above 100 °C for pure CBN30 ceramics, above 165 °C for CBN30 + 5% SrTiO3 and CBN30 + 5% KTaO3, and above 200 оС for CBN30 + 5% LiTaO3, there is a strong increase in dielectric losses. The contribution of dielectric losses to switching processes makes it impossible to determine the temperature of the ferroelectric phase transition for solid solutions based on CBN30 from the temperature dependences of dielectric hysteresis loops.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"71 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72800502","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 : 2023-01-01DOI: 10.21883/ftt.2023.01.53939.470
А. В. Силантьев
Energy spectrum exohedral fullerene С70Br10 with the Cs symmetry groups have been obtained within the Hubbard model and static fluctuation approximation. The energy states have been classified using the methods of group theory, and the allowed transitions in the energy spectra of molecule С70Br10 have been determined. On the basis of the energy spectrum of exohedral fullerene С70Br10 is given an interpretation of experimentally observed optical absorption bands molecule С70Br10.
{"title":"Энергетический спектр и спектр оптического поглощения экзоэдрального фуллерена С-=SUB=-70-=/SUB=-Br-=SUB=-10-=/SUB=- в модели Хаббарда","authors":"А. В. Силантьев","doi":"10.21883/ftt.2023.01.53939.470","DOIUrl":"https://doi.org/10.21883/ftt.2023.01.53939.470","url":null,"abstract":"Energy spectrum exohedral fullerene С70Br10 with the Cs symmetry groups have been obtained within the Hubbard model and static fluctuation approximation. The energy states have been classified using the methods of group theory, and the allowed transitions in the energy spectra of molecule С70Br10 have been determined. On the basis of the energy spectrum of exohedral fullerene С70Br10 is given an interpretation of experimentally observed optical absorption bands molecule С70Br10.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76517038","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 : 2023-01-01DOI: 10.21883/ftt.2023.09.56243.137
Юрий Викторович Князев, Ю. И. Кузьмин
The results of experimental studies of the optical properties of binary cubic compounds ScBi and YBi are presented. The features of the frequency dispersion of dielectric functions in the wavelength range 0.22-15 µm are determined.The anomalous behavior of spectral characteristics in the infrared region of the spectrum corresponds to the semi-metallic nature of these materials. A weak intraband contribution to low-energy optical conductivity is associated with the main feature of their electronic structure - the localization of the Fermi level in the region of a deep minimum of the density of states. The features of quantum light absorption are discussed on the basis of a comparative analysis of experimental and theoretical spectra of interband optical conductivity.
{"title":"Особенности оптических свойств полуметаллических соединений ScBi и YBi","authors":"Юрий Викторович Князев, Ю. И. Кузьмин","doi":"10.21883/ftt.2023.09.56243.137","DOIUrl":"https://doi.org/10.21883/ftt.2023.09.56243.137","url":null,"abstract":"The results of experimental studies of the optical properties of binary cubic compounds ScBi and YBi are presented. The features of the frequency dispersion of dielectric functions in the wavelength range 0.22-15 µm are determined.The anomalous behavior of spectral characteristics in the infrared region of the spectrum corresponds to the semi-metallic nature of these materials. A weak intraband contribution to low-energy optical conductivity is associated with the main feature of their electronic structure - the localization of the Fermi level in the region of a deep minimum of the density of states. The features of quantum light absorption are discussed on the basis of a comparative analysis of experimental and theoretical spectra of interband optical conductivity.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79245630","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 : 2023-01-01DOI: 10.21883/ftt.2023.07.55850.81
Д. В. Корабельников, И. А. Федоров
Based on the density functional theory, the effect of pressure on the structure and electronic properties of crystalline metal cyanamides Zn(CN2) and NaSc(CN2)2 has been studied. The negative linear compressibility of Zn(CN2) was revealed and its correlation with microscopic changes in the atomic structure under pressure was established. It is shown that NaSc(CN2)2 has a low compressibility (0.2 TPa-1) in a direction close to that of cyanamide anions. Based on the quantum topological analysis of the electron density, interatomic interactions were studied and it was found that the Zn-N and Sc-N bonds have a partially covalent character. The band gaps of Zn(CN2) and NaSc(CN2)2 at pressures up to 1 GPa have been determined and found to correspond to the UV range of 224-271 nm.
{"title":"Исследование сжимаемости цианамидов металлов и влияния давления на их электронные свойства","authors":"Д. В. Корабельников, И. А. Федоров","doi":"10.21883/ftt.2023.07.55850.81","DOIUrl":"https://doi.org/10.21883/ftt.2023.07.55850.81","url":null,"abstract":"Based on the density functional theory, the effect of pressure on the structure and electronic properties of crystalline metal cyanamides Zn(CN2) and NaSc(CN2)2 has been studied. The negative linear compressibility of Zn(CN2) was revealed and its correlation with microscopic changes in the atomic structure under pressure was established. It is shown that NaSc(CN2)2 has a low compressibility (0.2 TPa-1) in a direction close to that of cyanamide anions. Based on the quantum topological analysis of the electron density, interatomic interactions were studied and it was found that the Zn-N and Sc-N bonds have a partially covalent character. The band gaps of Zn(CN2) and NaSc(CN2)2 at pressures up to 1 GPa have been determined and found to correspond to the UV range of 224-271 nm.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78495344","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 : 2023-01-01DOI: 10.21883/ftt.2023.06.55640.17h
А. В. Свалов, Вячеслав Элизбарович Иванов, C.В. Андреев, В. Н. Лепаловский, Андрей Фещенко, Е. В. Кудюков, И. А. Макарочкин, Г. В. Курляндская
FeNi films in circular shape with 3 mm in diameter obtained by magnetron sputtering in the presence of a constant magnetic field of various configurations are studied. The presence of a field created by a permanent magnet with a diameter of 1.2 mm, the magnetization of which is oriented perpendicular to the plane of the substrate, leads to the formation of a vortex-like magnetic structure in the film, characterized by diffuse domain walls.
{"title":"Особенности плоскостной магнитной анизотропии и доменной структуры пленок FeNi, осажденных в присутствии магнитного поля различной конфигурации","authors":"А. В. Свалов, Вячеслав Элизбарович Иванов, C.В. Андреев, В. Н. Лепаловский, Андрей Фещенко, Е. В. Кудюков, И. А. Макарочкин, Г. В. Курляндская","doi":"10.21883/ftt.2023.06.55640.17h","DOIUrl":"https://doi.org/10.21883/ftt.2023.06.55640.17h","url":null,"abstract":"FeNi films in circular shape with 3 mm in diameter obtained by magnetron sputtering in the presence of a constant magnetic field of various configurations are studied. The presence of a field created by a permanent magnet with a diameter of 1.2 mm, the magnetization of which is oriented perpendicular to the plane of the substrate, leads to the formation of a vortex-like magnetic structure in the film, characterized by diffuse domain walls.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"329 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77592463","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 : 2023-01-01DOI: 10.21883/ftt.2023.02.54293.527
Максим Николаевич Ситников, С. С. Аплеснин, А. М. Харьков, Х. Абдельбаки, Ф В Зеленов
The components of the impedance, the impedance of the LuxMn1-xS solid solution (x < 0.2) in the temperature range of 80-500 K and the frequency of 100-106 Hz were studied. A change in the sign of the magnetoimpedance in concentration and temperature is found. The contribution of the reactive and active components to the magnetoimpedance is determined. The correlation of magnetoimpedance temperatures with the temperatures of the maximum attenuation of ultrasound and electrosound has been established. The frequency dependences of the reactive part of the impedance are described in the Cole-Cole model.
{"title":"Магнитоимпеданс в сульфиде марганца, замещенного лютецием","authors":"Максим Николаевич Ситников, С. С. Аплеснин, А. М. Харьков, Х. Абдельбаки, Ф В Зеленов","doi":"10.21883/ftt.2023.02.54293.527","DOIUrl":"https://doi.org/10.21883/ftt.2023.02.54293.527","url":null,"abstract":"The components of the impedance, the impedance of the LuxMn1-xS solid solution (x < 0.2) in the temperature range of 80-500 K and the frequency of 100-106 Hz were studied. A change in the sign of the magnetoimpedance in concentration and temperature is found. The contribution of the reactive and active components to the magnetoimpedance is determined. The correlation of magnetoimpedance temperatures with the temperatures of the maximum attenuation of ultrasound and electrosound has been established. The frequency dependences of the reactive part of the impedance are described in the Cole-Cole model.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"52 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76767371","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 : 2023-01-01DOI: 10.21883/ftt.2023.01.53927.478
М.М. Дегоев, Михаил Михайлович Афанасьев, В.К. Калевич, К. В. Кавокин, Н. В. Козырев, G. Karczewski, Юрий Георгиевич Кусраев
In tunnel-coupled quantum wells of different widths, it was found that the spin dynamics arising from resonant pulsed optical pumping of an exciton in the narrow well includes the dynamics of electron spin polarization in the wide well, although the electron level in the wide well is 55 meV lower than the electron level in the narrow well. An analysis of the obtained results showed that the observed effect is caused by the exchange interaction of spin-polarized electrons in the wide well with exciton states in the narrow well.
{"title":"Проявление обменного взаимодействия электронов, разделенных потенциальным барьером в двойных квантовых ямах, в эффекте Керра","authors":"М.М. Дегоев, Михаил Михайлович Афанасьев, В.К. Калевич, К. В. Кавокин, Н. В. Козырев, G. Karczewski, Юрий Георгиевич Кусраев","doi":"10.21883/ftt.2023.01.53927.478","DOIUrl":"https://doi.org/10.21883/ftt.2023.01.53927.478","url":null,"abstract":"In tunnel-coupled quantum wells of different widths, it was found that the spin dynamics arising from resonant pulsed optical pumping of an exciton in the narrow well includes the dynamics of electron spin polarization in the wide well, although the electron level in the wide well is 55 meV lower than the electron level in the narrow well. An analysis of the obtained results showed that the observed effect is caused by the exchange interaction of spin-polarized electrons in the wide well with exciton states in the narrow well.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74986241","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 : 2023-01-01DOI: 10.21883/ftt.2023.03.54754.562
С. Н. Каллаев, А. Г. Бакмаев, З. М. Омаров
The thermophysical properties of the ferroelectric PbFe0.5Nb0.5O3 in the temperature range 300–800 K are studied. Anomalies in the heat capacity and thermal diffusion are found in the region of the diffuse ferroelectric transition Tc~380 K, the Burns temperature Td~670 K, and the intermediate temperature T^*~470 K. The dominant phonon heat transfer mechanisms in a ferroelectric with a nanopolar structure.
{"title":"Теплофизические свойства и фазовые переходы сегнетоэлектрика PbFe-=SUB=-0.5-=/SUB=-Nb-=SUB=-0.5-=/SUB=-O-=SUB=-3-=/SUB=- в области высоких температур","authors":"С. Н. Каллаев, А. Г. Бакмаев, З. М. Омаров","doi":"10.21883/ftt.2023.03.54754.562","DOIUrl":"https://doi.org/10.21883/ftt.2023.03.54754.562","url":null,"abstract":"The thermophysical properties of the ferroelectric PbFe0.5Nb0.5O3 in the temperature range 300–800 K are studied. Anomalies in the heat capacity and thermal diffusion are found in the region of the diffuse ferroelectric transition Tc~380 K, the Burns temperature Td~670 K, and the intermediate temperature T^*~470 K. The dominant phonon heat transfer mechanisms in a ferroelectric with a nanopolar structure.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"438 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76471651","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 : 2023-01-01DOI: 10.21883/ftt.2023.02.54303.523
В.Я. Вальков, А.В. Головчан, И.Ф. Грибанов, Б.М. Тодрис, Е.П. Андрейченко, В. И. Митюк, А. В. Маширов
Using pnictides MnAs and germaindes Mn0.89Cr0.11NiGe as an example, the transformation of thermobaric features of their magnetic characteristics at high pressures is considered. A unified approach is used to describe paramagnetic (PM) structural transitions of the displacement type with a change in the symmetry PM(P63/mmc)-PM(Pnma) from hexagonal to orthorhombic. It is shown that the competition between the parameters of the structural and magnetic orders in both systems manifests itself differently in the stabilization and alternation of the so-called high-spin and low-spin magnetically ordered states initiated by pressure. As a consequence, the structural contribution in these systems weakens (MnAs) or enhances (Mn0.89Cr0.11NiGe ) the giant magnetocaloric effect in the temperature-baric region of the first-order magnetostructural phase transitions.
{"title":"Температурно-барические особенности магнитных характеристик в системах со структурными переходами типа смещения","authors":"В.Я. Вальков, А.В. Головчан, И.Ф. Грибанов, Б.М. Тодрис, Е.П. Андрейченко, В. И. Митюк, А. В. Маширов","doi":"10.21883/ftt.2023.02.54303.523","DOIUrl":"https://doi.org/10.21883/ftt.2023.02.54303.523","url":null,"abstract":"Using pnictides MnAs and germaindes Mn0.89Cr0.11NiGe as an example, the transformation of thermobaric features of their magnetic characteristics at high pressures is considered. A unified approach is used to describe paramagnetic (PM) structural transitions of the displacement type with a change in the symmetry PM(P63/mmc)-PM(Pnma) from hexagonal to orthorhombic. It is shown that the competition between the parameters of the structural and magnetic orders in both systems manifests itself differently in the stabilization and alternation of the so-called high-spin and low-spin magnetically ordered states initiated by pressure. As a consequence, the structural contribution in these systems weakens (MnAs) or enhances (Mn0.89Cr0.11NiGe ) the giant magnetocaloric effect in the temperature-baric region of the first-order magnetostructural phase transitions.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91036540","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 : 2023-01-01DOI: 10.21883/ftt.2023.06.55657.18h
С А Одинцов, А.С. Пташенко, Эдвин Гарривич Локк, Е. Н. Бегинин, Александр Владимирович Садовников
The possibility of frequency-selective propagation of spin waves in a magnonic microwave guide with a magnonic crystal consisting of two layers with different values of the saturation magnetization in the layers is demonstrated. It is shown that multimode propagation of spin waves can occur inside a two-layer structure in two frequency ranges, while the presence of a magnonic crystal on the surface of the structure leads to the manifestation of a band gap in one of the frequency ranges. At the same time, the process of propagation of a spin-wave signal is accompanied by a strong nonreciprocity, which manifests itself in a change in the amplitude-frequency characteristics when the direction of the external magnetic field is reversed, while the frequency range of the band gap differs depending on the direction of the field. The proposed concept of a two-layer spin-wave waveguide can underlie the manufacture of multichannel filters or magnonic logic devices.
{"title":"Распространение невзаимных спиновых волн в многослойном магнонном кристалле","authors":"С А Одинцов, А.С. Пташенко, Эдвин Гарривич Локк, Е. Н. Бегинин, Александр Владимирович Садовников","doi":"10.21883/ftt.2023.06.55657.18h","DOIUrl":"https://doi.org/10.21883/ftt.2023.06.55657.18h","url":null,"abstract":"The possibility of frequency-selective propagation of spin waves in a magnonic microwave guide with a magnonic crystal consisting of two layers with different values of the saturation magnetization in the layers is demonstrated. It is shown that multimode propagation of spin waves can occur inside a two-layer structure in two frequency ranges, while the presence of a magnonic crystal on the surface of the structure leads to the manifestation of a band gap in one of the frequency ranges. At the same time, the process of propagation of a spin-wave signal is accompanied by a strong nonreciprocity, which manifests itself in a change in the amplitude-frequency characteristics when the direction of the external magnetic field is reversed, while the frequency range of the band gap differs depending on the direction of the field. The proposed concept of a two-layer spin-wave waveguide can underlie the manufacture of multichannel filters or magnonic logic devices.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73567774","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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