Pub Date : 2023-01-01DOI: 10.21883/ftt.2023.07.55854.63
В. И. Зиненко
Low-temperature thermodynamic properties of spin ice have been studied for compounds with the structure of antiperovskite containing rare-earth ions with the general chemical formula Romeo (where Re is a rare-earth element, Me is a divalent metal). The calculations were carried out in the cluster approximation. The cases of undistorted and distorted ORE 6 octahedron are discussed. In the case of an undistorted octahedron in the absence of an external magnetic field, the ground state of the system is infinitely degenerate. When an external magnetic field is applied, anomalies in the temperature dependences of heat capacity, entropy and magnetization are detected. In the case of a distorted octahedron and assuming that this distortion leads to the energy efficiency of two of the sixty-four configurations, it is obtained that there is a phase transition in the system of magnetic rare-earth ions
{"title":"Термодинамика спинового льда на решетке антиперовскита в приближении кластеров","authors":"В. И. Зиненко","doi":"10.21883/ftt.2023.07.55854.63","DOIUrl":"https://doi.org/10.21883/ftt.2023.07.55854.63","url":null,"abstract":"Low-temperature thermodynamic properties of spin ice have been studied for compounds with the structure of antiperovskite containing rare-earth ions with the general chemical formula Romeo (where Re is a rare-earth element, Me is a divalent metal). The calculations were carried out in the cluster approximation. The cases of undistorted and distorted ORE 6 octahedron are discussed. In the case of an undistorted octahedron in the absence of an external magnetic field, the ground state of the system is infinitely degenerate. When an external magnetic field is applied, anomalies in the temperature dependences of heat capacity, entropy and magnetization are detected. In the case of a distorted octahedron and assuming that this distortion leads to the energy efficiency of two of the sixty-four configurations, it is obtained that there is a phase transition in the system of magnetic rare-earth ions","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"73 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76472208","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.2023.09.56247.164
А.И. Наджафов, Т. Г. Мамедов, Х.В. Алигулиева, С.Ш. Кахраманов, В. Б. Алиева, Владимир Николаевич Зверев, Н. А. Абдуллаев
Electrical and galvanomagnetic effects in single crystals of Bi0.9Sb0.1 solid solutions doped with 1 and 3 at.% Mn have been studied. It is shown that in single crystals of Bi0.9Sb0.1 solid solutions doped with 1 at.% Mn at temperatures below 180 K, activation conductiity with an activation energy of 10 meV is observed. After thermal annealing, in addition to activation conductivity, at temperatures below 20 K, a “metallic” character of conductivity is observed, which is due to conduction over the impurity band. It was found that in single crystals of Bi0.9Sb0.1 solid solutions doped with 3 at.% Mn, a “metallic” character of conductivity is observed with a feature at low temperatures of about 25 K, which reacts to applied external magnetic fields. After thermal annealing, the “metallic” nature of the conductivity is retained, but this feature practically disappears. The mobility and concentration of charge carriers are estimated.
{"title":"Перенос заряда в твердых растворах Bi-=SUB=-0.9-=/SUB=-Sb-=SUB=-0.1-=/SUB=-, легированных Mn","authors":"А.И. Наджафов, Т. Г. Мамедов, Х.В. Алигулиева, С.Ш. Кахраманов, В. Б. Алиева, Владимир Николаевич Зверев, Н. А. Абдуллаев","doi":"10.21883/ftt.2023.09.56247.164","DOIUrl":"https://doi.org/10.21883/ftt.2023.09.56247.164","url":null,"abstract":"Electrical and galvanomagnetic effects in single crystals of Bi0.9Sb0.1 solid solutions doped with 1 and 3 at.% Mn have been studied. It is shown that in single crystals of Bi0.9Sb0.1 solid solutions doped with 1 at.% Mn at temperatures below 180 K, activation conductiity with an activation energy of 10 meV is observed. After thermal annealing, in addition to activation conductivity, at temperatures below 20 K, a “metallic” character of conductivity is observed, which is due to conduction over the impurity band. It was found that in single crystals of Bi0.9Sb0.1 solid solutions doped with 3 at.% Mn, a “metallic” character of conductivity is observed with a feature at low temperatures of about 25 K, which reacts to applied external magnetic fields. After thermal annealing, the “metallic” nature of the conductivity is retained, but this feature practically disappears. The mobility and concentration of charge carriers are estimated.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84532062","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.2023.04.55309.16
А. В. Яценко
The features of the surface electrical conductivity of a series of LiNbO3 crystals of different compositions are studied. It is shown that when the crystals are cooled, H2O molecules are adsorbed and dissociated on their polar surfaces, and the intensity of this process depends on the unipolarity of the sample.
{"title":"Особенности адсорбции Н-=SUB=-2-=/SUB=-О на полярных поверхностях кристаллов LiNbO-=SUB=-3-=/SUB=-","authors":"А. В. Яценко","doi":"10.21883/ftt.2023.04.55309.16","DOIUrl":"https://doi.org/10.21883/ftt.2023.04.55309.16","url":null,"abstract":"The features of the surface electrical conductivity of a series of LiNbO3 crystals of different compositions are studied. It is shown that when the crystals are cooled, H2O molecules are adsorbed and dissociated on their polar surfaces, and the intensity of this process depends on the unipolarity of the sample.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"58 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84860313","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.2023.07.55852.98
М.А. Ормонт, Н.В. Валенко
The peculiarities of the behavior of high-frequency conductivity of disordered semiconductors associated with the hopping transport of electrons in the impurity band with increasing temperature were studied. Via the pair approximation, it is shown that the transition (crossover) observed at low temperatures (T ≈ 1 K) in the terahertz frequency range from an almost linear to a quadratic frequency dependence of the real part of conductivity can stay on with increasing temperature and be caused by the transition from relaxation conductivity with a variable-range (frequency-dependent) hopping distance to phononless conductivity with a fixed- range hopping distance.
{"title":"Особенности поведения высокочастотной проводимости неупорядоченных полупроводников с ростом температуры","authors":"М.А. Ормонт, Н.В. Валенко","doi":"10.21883/ftt.2023.07.55852.98","DOIUrl":"https://doi.org/10.21883/ftt.2023.07.55852.98","url":null,"abstract":"The peculiarities of the behavior of high-frequency conductivity of disordered semiconductors associated with the hopping transport of electrons in the impurity band with increasing temperature were studied. Via the pair approximation, it is shown that the transition (crossover) observed at low temperatures (T ≈ 1 K) in the terahertz frequency range from an almost linear to a quadratic frequency dependence of the real part of conductivity can stay on with increasing temperature and be caused by the transition from relaxation conductivity with a variable-range (frequency-dependent) hopping distance to phononless conductivity with a fixed- range hopping distance.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85470103","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.2023.06.55638.08h
А. С. Русалина, В. Н. Лепаловский, Екатерина Андреевна Степанова, В. О. Васьковский, Г. В. Курляндская, А. В. Свалов
Triple hysteresis loops were observed for amorphous ferrimagnetic Gd-Co films near the magnetic compensation temperature, which can be a consequence of both the spin-flop transition and the chemical composition gradient. In the work, an assessment of the possible chemical inhomogeneity of the films based on magnetic measurements was carried out and its relationship with the thickness of the samples was observed.
{"title":"Аномальные петли гистерезиса ферримагнитных пленок Gd-Co различной толщины вблизи температуры магнитной компенсации","authors":"А. С. Русалина, В. Н. Лепаловский, Екатерина Андреевна Степанова, В. О. Васьковский, Г. В. Курляндская, А. В. Свалов","doi":"10.21883/ftt.2023.06.55638.08h","DOIUrl":"https://doi.org/10.21883/ftt.2023.06.55638.08h","url":null,"abstract":"Triple hysteresis loops were observed for amorphous ferrimagnetic Gd-Co films near the magnetic compensation temperature, which can be a consequence of both the spin-flop transition and the chemical composition gradient. In the work, an assessment of the possible chemical inhomogeneity of the films based on magnetic measurements was carried out and its relationship with the thickness of the samples was observed.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76861930","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.2023.06.55655.15h
М. В. Дорохин, П.Б. Дёмина, А. В. Здоровейщев, Д.А. Здоровейщев, А. Г. Темирязев, М. П. Темирязева, И.Л. Калентьева, В. Н. Трушин
The magnetic properties and micromagnetic structure of [Co/Pt]10 multilayer magnetic films formed by independent variation of the Co and Pt layer thicknesses have been studied. The possibility of the film magnetization parameters manipulation was shown. It is found that the micromagnetic structure of the layers is significantly modified with a change in the thickness of the layers which correlates with the magnetization data. In particular, magnetic force microscopy revealed a system of magnetic skyrmions for a number of structures. The skyrmion density was found to be dependent on the growth conditions which in turn correlates with the shape of the magnetic hysteresis loop. Changing the thickness of the Co and Pt layers makes it possible to control the density of skyrmions in the range from 0.2 to 10.5 µm-2.
{"title":"Управление микромагнитной структурой многофазных тонких пленок CoPt путем варьирования толщин слоев","authors":"М. В. Дорохин, П.Б. Дёмина, А. В. Здоровейщев, Д.А. Здоровейщев, А. Г. Темирязев, М. П. Темирязева, И.Л. Калентьева, В. Н. Трушин","doi":"10.21883/ftt.2023.06.55655.15h","DOIUrl":"https://doi.org/10.21883/ftt.2023.06.55655.15h","url":null,"abstract":"The magnetic properties and micromagnetic structure of [Co/Pt]10 multilayer magnetic films formed by independent variation of the Co and Pt layer thicknesses have been studied. The possibility of the film magnetization parameters manipulation was shown. It is found that the micromagnetic structure of the layers is significantly modified with a change in the thickness of the layers which correlates with the magnetization data. In particular, magnetic force microscopy revealed a system of magnetic skyrmions for a number of structures. The skyrmion density was found to be dependent on the growth conditions which in turn correlates with the shape of the magnetic hysteresis loop. Changing the thickness of the Co and Pt layers makes it possible to control the density of skyrmions in the range from 0.2 to 10.5 µm-2.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76866240","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.2023.06.55639.14h
Е. А. Денисова, Лидия А. Чеканова, C.В. Комогорцев, Р. С. Исхаков, О. А. Ли, А.Л. Сухачев, Дмитрий Анатольевич Великанов, И.В. Немцев
The structural and magnetic properties of nanostructured Fe-Ni‒C coatings produced by electroless plating with different carbohydrates as reducing agents have been investigated. The phase-structural state of the films was studied by X-ray diffraction and electron microscopy. The Ni concentration ranges of FCC and BCC phases existence in electroless deposited Fe-Ni‒C films were determined. The surface morphology, saturation magnetization, local magnetic anisotropy field and coercivities of FeNi-C films are dependent on the iron content and type of reducing agent. The correlation between coercivity and the anisotropy field of the magnetic stochastic domain which were established by correlation magnetometry suggests that the magnitude of Hc is mainly determined by this anisotropy
{"title":"Магнитная анизотропия наноструктурированных покрытий Fe-Ni-C, полученных методом химического осаждения","authors":"Е. А. Денисова, Лидия А. Чеканова, C.В. Комогорцев, Р. С. Исхаков, О. А. Ли, А.Л. Сухачев, Дмитрий Анатольевич Великанов, И.В. Немцев","doi":"10.21883/ftt.2023.06.55639.14h","DOIUrl":"https://doi.org/10.21883/ftt.2023.06.55639.14h","url":null,"abstract":"The structural and magnetic properties of nanostructured Fe-Ni‒C coatings produced by electroless plating with different carbohydrates as reducing agents have been investigated. The phase-structural state of the films was studied by X-ray diffraction and electron microscopy. The Ni concentration ranges of FCC and BCC phases existence in electroless deposited Fe-Ni‒C films were determined. The surface morphology, saturation magnetization, local magnetic anisotropy field and coercivities of FeNi-C films are dependent on the iron content and type of reducing agent. The correlation between coercivity and the anisotropy field of the magnetic stochastic domain which were established by correlation magnetometry suggests that the magnitude of Hc is mainly determined by this anisotropy","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"92 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81248173","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.2023.05.55503.27
Андрей Владимирович Андрианов, А. Н. Алешин, С.Н. Аболмасов, Е.И. Теруков, А.О. Захарьин
The results of studying the generation of terahertz (THz) radiation in p-n-heterostructures based on a-Si:H//c-Si upon their photoexcitation by radiation from a femtosecond titanium-sapphire laser with a wavelength of 800 nm are presented. The properties of the observed THz radiation can be explained by excitation of fast photocurrent of nonequilibrium charge carriers created in the region of the potential barrier under femtosecond interband photoexcitation of the structure. The fast photocurrent, in turn, emits a THz electromagnetic wave. The waveforms and amplitude spectra of the observed THz radiation reflect the dynamics of photoexcited charge carriers in structures. In terms of intensity, the THz radiation observed from the studied p–n heterostructures based on a-Si:H//c-Si is comparable to the THz radiation generated in n-InAs crystals, which are widely used as emitters in systems of THz time-domain spectroscopy. Therefore, a-Si:H//c-Si p-n-heterostructures can be used as THz emitters for solving tasks of THz spectroscopy.
{"title":"Возбуждение терагерцевого излучения в p-n-гетероструктурах на основе a-Si:H/c-Si","authors":"Андрей Владимирович Андрианов, А. Н. Алешин, С.Н. Аболмасов, Е.И. Теруков, А.О. Захарьин","doi":"10.21883/ftt.2023.05.55503.27","DOIUrl":"https://doi.org/10.21883/ftt.2023.05.55503.27","url":null,"abstract":"The results of studying the generation of terahertz (THz) radiation in p-n-heterostructures based on a-Si:H//c-Si upon their photoexcitation by radiation from a femtosecond titanium-sapphire laser with a wavelength of 800 nm are presented. The properties of the observed THz radiation can be explained by excitation of fast photocurrent of nonequilibrium charge carriers created in the region of the potential barrier under femtosecond interband photoexcitation of the structure. The fast photocurrent, in turn, emits a THz electromagnetic wave. The waveforms and amplitude spectra of the observed THz radiation reflect the dynamics of photoexcited charge carriers in structures. In terms of intensity, the THz radiation observed from the studied p–n heterostructures based on a-Si:H//c-Si is comparable to the THz radiation generated in n-InAs crystals, which are widely used as emitters in systems of THz time-domain spectroscopy. Therefore, a-Si:H//c-Si p-n-heterostructures can be used as THz emitters for solving tasks of THz spectroscopy.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85401570","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.2023.08.56154.83
Л В Удод, С. С. Аплеснин, Максим Николаевич Ситников, О. Б. Романова
The composite compound Bi2(Sn0.7Fe0.3)2O7/Bi2Fe4O9 in the ratio 91/9% was synthesized by the solid-phase reaction method. The current-voltage characteristics were studied in the temperature range 800-400 K. The hysteresis of the current-voltage characteristics was found. The magnetoelectric interaction and thermoelectric power have been studied. The temperatures of predominance of the even and linear functions of the magnetoelectric effect are established. The sign change of the thermopower has been found.
{"title":"Исследование магнитоэлектрического эффекта и термоэдс в композитном железозамещенном пиростаннате висмута Bi-=SUB=-2-=/SUB=-(Sn0-=SUB=-0.7-=/SUB=-Fe-=SUB=-0.3-=/SUB=-)-=SUB=-2-=/SUB=-O-=SUB=-7-=/SUB=-/Bi-=SUB=-2-=/SUB=-Fe-=SUB=-4-=/SUB=-O-=SUB=-9-=/SUB=-","authors":"Л В Удод, С. С. Аплеснин, Максим Николаевич Ситников, О. Б. Романова","doi":"10.21883/ftt.2023.08.56154.83","DOIUrl":"https://doi.org/10.21883/ftt.2023.08.56154.83","url":null,"abstract":"The composite compound Bi2(Sn0.7Fe0.3)2O7/Bi2Fe4O9 in the ratio 91/9% was synthesized by the solid-phase reaction method. The current-voltage characteristics were studied in the temperature range 800-400 K. The hysteresis of the current-voltage characteristics was found. The magnetoelectric interaction and thermoelectric power have been studied. The temperatures of predominance of the even and linear functions of the magnetoelectric effect are established. The sign change of the thermopower has been found.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85703184","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.2023.09.56252.143
А. Д. Балаев, В.H. Воронов, В.М. Соснин, Дмитрий А. Балаев
The static magnetic properties of the Rb2KFeF6 single crystal in the temperature range T=1.8-300 K in magnetic fields H up to 90 kOe are investigated. At T>1.8 K the crystal is not magnetically ordered, however, the behavior of the inverse susceptibility chi-1(T) indicates a negative paramagnetic Curie temperature Theta of ~0.8 K. This is consistent with the analysis of the magnetization curve M(H) by replacing the external field with an effective Heff field with a negative molecular field constant.
{"title":"Магнитные свойства Rb-=SUB=-2-=/SUB=-KFeF-=SUB=-6-=/SUB=-","authors":"А. Д. Балаев, В.H. Воронов, В.М. Соснин, Дмитрий А. Балаев","doi":"10.21883/ftt.2023.09.56252.143","DOIUrl":"https://doi.org/10.21883/ftt.2023.09.56252.143","url":null,"abstract":"The static magnetic properties of the Rb2KFeF6 single crystal in the temperature range T=1.8-300 K in magnetic fields H up to 90 kOe are investigated. At T>1.8 K the crystal is not magnetically ordered, however, the behavior of the inverse susceptibility chi-1(T) indicates a negative paramagnetic Curie temperature Theta of ~0.8 K. This is consistent with the analysis of the magnetization curve M(H) by replacing the external field with an effective Heff field with a negative molecular field constant.","PeriodicalId":24077,"journal":{"name":"Физика твердого тела","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78525985","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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