Pub Date : 2012-09-01DOI: 10.1109/OMEE.2012.6464776
L. Yurchenko, I. Bykov, A. Vasylyev, V. Vereshchak, G. Suchaneck, L. Jastrabík, A. Dejneka
Formation mechanisms of paramagnetic centers originating from Zr3+ and Cr3+ ions as well as the influence of composition of nanoparticles on thermogeneration processes of these paramagnetic centers in ZrO2 structure were studied. A set of nanosized powders of zirconium oxide was investigated by electron paramagnetic resonance method: nominally pure ZrO2; ZrO2 with Y2O3 and Sc2O3; ZrO2 with Cr2O3; ZrO2 with Y2O3 and Cr2O3. It is observed that the influence of annealing on EPR lines of Zr3+ and Cr3+ ions is different. Nuclear magnetic resonance data have shown that zirconium dioxide nanoparticles with Sc and Y impurities include two types of water molecules and two types of hydroxyl groups.
{"title":"Defect structure of zirconium oxide nanosized powders with Y2O3, Sc2O3, Cr2O3 impurities","authors":"L. Yurchenko, I. Bykov, A. Vasylyev, V. Vereshchak, G. Suchaneck, L. Jastrabík, A. Dejneka","doi":"10.1109/OMEE.2012.6464776","DOIUrl":"https://doi.org/10.1109/OMEE.2012.6464776","url":null,"abstract":"Formation mechanisms of paramagnetic centers originating from Zr<sup>3+</sup> and Cr<sup>3+</sup> ions as well as the influence of composition of nanoparticles on thermogeneration processes of these paramagnetic centers in ZrO<inf>2</inf> structure were studied. A set of nanosized powders of zirconium oxide was investigated by electron paramagnetic resonance method: nominally pure ZrO<inf>2</inf>; ZrO<inf>2</inf> with Y<inf>2</inf>O<inf>3</inf> and Sc<inf>2</inf>O<inf>3</inf>; ZrO<inf>2</inf> with Cr<inf>2</inf>O<inf>3</inf>; ZrO<inf>2</inf> with Y<inf>2</inf>O<inf>3</inf> and Cr<inf>2</inf>O<inf>3</inf>. It is observed that the influence of annealing on EPR lines of Zr<sup>3+</sup> and Cr<sup>3+</sup> ions is different. Nuclear magnetic resonance data have shown that zirconium dioxide nanoparticles with Sc and Y impurities include two types of water molecules and two types of hydroxyl groups.","PeriodicalId":6332,"journal":{"name":"2012 IEEE International Conference on Oxide Materials for Electronic Engineering (OMEE)","volume":"6 1","pages":"114-115"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87917522","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 : 2012-09-01DOI: 10.1109/OMEE.2012.6464840
R. Tandon, R. Mishra
An explicit role of viscosity on the growth of semiconductor nanocrystals dispersed in silicate glass matrix is investigated. Theoretically, a simplified Arrhenius equation, lnη = A + B/T (where η is viscosity) is used to calculate the viscosities of various glass compositions. Using Diffusion - Controlled Growth model it is established that average radius of grain (QD) is inversely proportional to the cube root of the viscosity of supersaturated solid solution. Experimental evidences show that grown dot size is ranging from 2nm to 20 nm for various growth times (2–50 hr). A blue shift was observed in optical absorption edge. The optical absorption spectra depict that bang gap of CdS quantum dots ranges from bulk band gap 2.4eV to 3.2eV which confirms the strong confinement of quantum dots. Photoluminescence measurements explain the observed absorption results qualitatively. CdS doped glass samples showed the red shift of emission wavelength as the thermal treatment time and temperature increased which justifies the viscosity dependence on cluster size.
{"title":"Viscosity dependant CdS nanocrystals embedded in silicate glass","authors":"R. Tandon, R. Mishra","doi":"10.1109/OMEE.2012.6464840","DOIUrl":"https://doi.org/10.1109/OMEE.2012.6464840","url":null,"abstract":"An explicit role of viscosity on the growth of semiconductor nanocrystals dispersed in silicate glass matrix is investigated. Theoretically, a simplified Arrhenius equation, lnη = A + B/T (where η is viscosity) is used to calculate the viscosities of various glass compositions. Using Diffusion - Controlled Growth model it is established that average radius of grain (QD) is inversely proportional to the cube root of the viscosity of supersaturated solid solution. Experimental evidences show that grown dot size is ranging from 2nm to 20 nm for various growth times (2–50 hr). A blue shift was observed in optical absorption edge. The optical absorption spectra depict that bang gap of CdS quantum dots ranges from bulk band gap 2.4eV to 3.2eV which confirms the strong confinement of quantum dots. Photoluminescence measurements explain the observed absorption results qualitatively. CdS doped glass samples showed the red shift of emission wavelength as the thermal treatment time and temperature increased which justifies the viscosity dependence on cluster size.","PeriodicalId":6332,"journal":{"name":"2012 IEEE International Conference on Oxide Materials for Electronic Engineering (OMEE)","volume":"5 1","pages":"67-68"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88447460","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 : 2012-09-01DOI: 10.1109/OMEE.2012.6464780
V. Vashook, J. Rebello, J. Chen, L. Vasylechko, D. Trots, J. Zosel, U. Guth
Crystal structure, thermal expansion, oxygen non-stoichiometry, electrical conductivity and diffusion characteristics of two analogous LaFe0.7Ni0.3O3−δ and PrFe0.7Ni0.3O3−δ compositions were investigated depending on temperature (20–1000 °C) and oxygen partial pressure (0.6–21000 Pa). The found oxygen diffusion and oxygen exchange coefficients for the both compositions at similar conditions are near to each other and varied in the range of 1·10−7–1·10−5 cm2·s−1 and 5·10−6–1·10−4 cm·s−1, respectively.
{"title":"Crystal structure, oxygen nonstoichiometry and diffusion mobility in some ferrites-nickelites","authors":"V. Vashook, J. Rebello, J. Chen, L. Vasylechko, D. Trots, J. Zosel, U. Guth","doi":"10.1109/OMEE.2012.6464780","DOIUrl":"https://doi.org/10.1109/OMEE.2012.6464780","url":null,"abstract":"Crystal structure, thermal expansion, oxygen non-stoichiometry, electrical conductivity and diffusion characteristics of two analogous LaFe<inf>0.7</inf>Ni<inf>0.3</inf>O<inf>3−δ</inf> and PrFe<inf>0.7</inf>Ni<inf>0.3</inf>O<inf>3−δ</inf> compositions were investigated depending on temperature (20–1000 °C) and oxygen partial pressure (0.6–21000 Pa). The found oxygen diffusion and oxygen exchange coefficients for the both compositions at similar conditions are near to each other and varied in the range of 1·10<sup>−7</sup>–1·10<sup>−5</sup> cm<sup>2</sup>·s<sup>−1</sup> and 5·10<sup>−6</sup>–1·10<sup>−4</sup> cm·s<sup>−1</sup>, respectively.","PeriodicalId":6332,"journal":{"name":"2012 IEEE International Conference on Oxide Materials for Electronic Engineering (OMEE)","volume":"10 1","pages":"105-106"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86544897","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 : 2012-09-01DOI: 10.1109/OMEE.2012.6464750
V. Shevchuk, A. Luchechko, Yu.N. Usatenko, I. Kayun, D. Sugak
The multi-band luminescence and the excitation spectra, and the spectral reflectance of the undoped V2O5 in nano- and bulk-crystalline form at room temperature in the spectral range 200–900 nm were investigated. The nature of luminescence (peaked about 650 nm) is discussed with account of reflectance spectra and Electron Paramagnetic Resonance (EPR) investigations.
{"title":"Optical properties of V2O5 crystals","authors":"V. Shevchuk, A. Luchechko, Yu.N. Usatenko, I. Kayun, D. Sugak","doi":"10.1109/OMEE.2012.6464750","DOIUrl":"https://doi.org/10.1109/OMEE.2012.6464750","url":null,"abstract":"The multi-band luminescence and the excitation spectra, and the spectral reflectance of the undoped V2O5 in nano- and bulk-crystalline form at room temperature in the spectral range 200–900 nm were investigated. The nature of luminescence (peaked about 650 nm) is discussed with account of reflectance spectra and Electron Paramagnetic Resonance (EPR) investigations.","PeriodicalId":6332,"journal":{"name":"2012 IEEE International Conference on Oxide Materials for Electronic Engineering (OMEE)","volume":"11 1","pages":"223-224"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83312932","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 : 2012-09-01DOI: 10.1109/OMEE.2012.6464775
T. Tataryn, L. Vasylechko, D. Savytskii, M. Berkowski, C. Paulmann, U. Bismayer
The structure of perovskite-type La0.95Sr0.05Ga0.95Mn0.05O3−x crystals has been investigated using high-resolution X-ray powder diffraction technique in the temperature range of 298–1173 K. A phase transition from orthorhombic (Pbnm) to rhombohedral (R 3 c) has been detected near 340 K. A chevron-like configuration of ferroelastic domain structure was observed in rhombohedral La0.95Sr0.05Ga0.95Mn0.05O3−x crystal using the Laue technique. The chevron-like pattern is formed by the intersection of W-type domain walls (211), (101) and (110).
{"title":"Crystal and twin structure of LSGMn-05 anode material for SOFC","authors":"T. Tataryn, L. Vasylechko, D. Savytskii, M. Berkowski, C. Paulmann, U. Bismayer","doi":"10.1109/OMEE.2012.6464775","DOIUrl":"https://doi.org/10.1109/OMEE.2012.6464775","url":null,"abstract":"The structure of perovskite-type La<inf>0.95</inf>Sr<inf>0.05</inf>Ga<inf>0.95</inf>Mn<inf>0.05</inf>O<inf>3−x</inf> crystals has been investigated using high-resolution X-ray powder diffraction technique in the temperature range of 298–1173 K. A phase transition from orthorhombic (Pbnm) to rhombohedral (R 3 c) has been detected near 340 K. A chevron-like configuration of ferroelastic domain structure was observed in rhombohedral La<inf>0.95</inf>Sr<inf>0.05</inf>Ga<inf>0.95</inf>Mn<inf>0.05</inf>O<inf>3−x</inf> crystal using the Laue technique. The chevron-like pattern is formed by the intersection of W-type domain walls (211), (101) and (110).","PeriodicalId":6332,"journal":{"name":"2012 IEEE International Conference on Oxide Materials for Electronic Engineering (OMEE)","volume":"25 3 1","pages":"116-117"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77260315","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 : 2012-09-01DOI: 10.1109/OMEE.2012.6464860
N. Slobodyanik, K. Terebilenko, I. Zatovsky, V. Baumer
The main crystallization trends of complex oxide compounds of lanthanides from alkaline phosphate-molybdate (tungstate) melts have been studied in light of structure - luminescence properties relationships. The regions of formation MI3Ln(PO4)2, LnPO4, K2Ln(PO4)(MVIO4), MIMIII(MVIO4)2 from self flux systems MI-P-Ln-O (MI-alkaline metal; MVI-Mo, W) have been defined. The influence of MI/MVI ratio in the initial melt has been shown to play the key role in solid phase formation and structural peculiarities of LnOx polyhedral condensation of compounds obtained.
{"title":"Synthesis, structure and luminescence properties of lanthanide compounds grown from phosphate-molybdate molten systems","authors":"N. Slobodyanik, K. Terebilenko, I. Zatovsky, V. Baumer","doi":"10.1109/OMEE.2012.6464860","DOIUrl":"https://doi.org/10.1109/OMEE.2012.6464860","url":null,"abstract":"The main crystallization trends of complex oxide compounds of lanthanides from alkaline phosphate-molybdate (tungstate) melts have been studied in light of structure - luminescence properties relationships. The regions of formation M<sup>I</sup>3Ln(PO<inf>4</inf>)<inf>2</inf>, LnPO<inf>4</inf>, K<inf>2</inf>Ln(PO<inf>4</inf>)(M<sup>VI</sup>O<inf>4</inf>), M<sup>I</sup>M<sup>III</sup>(M<sup>VI</sup>O<inf>4</inf>)<inf>2</inf> from self flux systems M<sup>I</sup>-P-Ln-O (M<sup>I</sup>-alkaline metal; M<sup>VI</sup>-Mo, W) have been defined. The influence of M<sup>I</sup>/M<sup>VI</sup> ratio in the initial melt has been shown to play the key role in solid phase formation and structural peculiarities of LnOx polyhedral condensation of compounds obtained.","PeriodicalId":6332,"journal":{"name":"2012 IEEE International Conference on Oxide Materials for Electronic Engineering (OMEE)","volume":"31 1","pages":"25-26"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90846722","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 : 2012-09-01DOI: 10.1109/OMEE.2012.6464733
E. Vasko, I. Melnichuk
Trajectories of the movement of electrons scattered by a thin magnetic film of Sm1.2Lu1.8Fe5O12 with a stripe domain structure (SDS) have been computed. It has been shown that the domain structure considerably influences the nature of the electrons scattering and results in a number of orientational effects.
{"title":"Thin films of magnetic oxides as a tool for control of a charged particles beam","authors":"E. Vasko, I. Melnichuk","doi":"10.1109/OMEE.2012.6464733","DOIUrl":"https://doi.org/10.1109/OMEE.2012.6464733","url":null,"abstract":"Trajectories of the movement of electrons scattered by a thin magnetic film of Sm<inf>1.2</inf>Lu<inf>1.8</inf>Fe<inf>5</inf>O<inf>12</inf> with a stripe domain structure (SDS) have been computed. It has been shown that the domain structure considerably influences the nature of the electrons scattering and results in a number of orientational effects.","PeriodicalId":6332,"journal":{"name":"2012 IEEE International Conference on Oxide Materials for Electronic Engineering (OMEE)","volume":"77 1","pages":"262-263"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89632723","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 : 2012-09-01DOI: 10.1109/OMEE.2012.6464826
O. Dolotko, A. Senyshyn, M.J. Muhlbauer, K. Nikolowski, H. Ehrenberg
In situ high-resolution neutron powder diffraction along with electrochemical analysis was used to study fatigue processes in commercial LiCoO2 (18650-type) batteries. The electrochemical and structural behavior of cathode and anode materials in fully charged and discharged states has been studied for cells exhibiting different cycling at 25°C and 50°C. High-resolution neutron powder diffraction leads us to observe simultaneous changes in LiCoO2 cathode and graphitic anode, which are related to lithium de-/intercalation processes during the battery operation. Detailed features of the battery organization and details of its evolution on a micrometer scale have been visualized using neutron radiography and tomography.
{"title":"Fatigue processes in commercial LiCoO2 batteries: In situ neutron diffraction and electrochemical study","authors":"O. Dolotko, A. Senyshyn, M.J. Muhlbauer, K. Nikolowski, H. Ehrenberg","doi":"10.1109/OMEE.2012.6464826","DOIUrl":"https://doi.org/10.1109/OMEE.2012.6464826","url":null,"abstract":"In situ high-resolution neutron powder diffraction along with electrochemical analysis was used to study fatigue processes in commercial LiCoO2 (18650-type) batteries. The electrochemical and structural behavior of cathode and anode materials in fully charged and discharged states has been studied for cells exhibiting different cycling at 25°C and 50°C. High-resolution neutron powder diffraction leads us to observe simultaneous changes in LiCoO2 cathode and graphitic anode, which are related to lithium de-/intercalation processes during the battery operation. Detailed features of the battery organization and details of its evolution on a micrometer scale have been visualized using neutron radiography and tomography.","PeriodicalId":6332,"journal":{"name":"2012 IEEE International Conference on Oxide Materials for Electronic Engineering (OMEE)","volume":"24 1","pages":"96-96"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90399704","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 : 2012-09-01DOI: 10.1109/OMEE.2012.6464781
L. Vasylechko, A. Bell
Phase and structural behaviour of new mixed cobaltites R1−xR′xCoO3 (R, RR′ = La, Pr, Nd, Sm, Eu, Gd) and cobaltites-chromites RCo0.5Cr0.5O3 (R = Pr, Sm, Eu, Gd) has been studied in the temperature range of 298–1173K. Strong anomalies in the lattice expansion reflecting the changes in spin state of Co3+ ions, are found. Correlations between the structural parameters, characteristic temperatures of thermal expansion coefficients and the temperatures of spin-state transitions in the mixed RE cobaltites has been established.
{"title":"Influence of cation substitution on spin-state transitions in mixed RE cobaltites and chromites","authors":"L. Vasylechko, A. Bell","doi":"10.1109/OMEE.2012.6464781","DOIUrl":"https://doi.org/10.1109/OMEE.2012.6464781","url":null,"abstract":"Phase and structural behaviour of new mixed cobaltites R<inf>1−x</inf>R′xCoO<inf>3</inf> (R, RR′ = La, Pr, Nd, Sm, Eu, Gd) and cobaltites-chromites RCo<inf>0.5</inf>Cr0.5O<inf>3</inf> (R = Pr, Sm, Eu, Gd) has been studied in the temperature range of 298–1173K. Strong anomalies in the lattice expansion reflecting the changes in spin state of Co<sup>3+</sup> ions, are found. Correlations between the structural parameters, characteristic temperatures of thermal expansion coefficients and the temperatures of spin-state transitions in the mixed RE cobaltites has been established.","PeriodicalId":6332,"journal":{"name":"2012 IEEE International Conference on Oxide Materials for Electronic Engineering (OMEE)","volume":"1 1","pages":"103-104"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75047011","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 : 2012-09-01DOI: 10.1109/OMEE.2012.6464823
O. Kuz, V. Handysh, Y. Prots, L. Vasylechko
The work deals with the study of the phase and structural behaviour of the rare-earth substituted BiFeO3. X-ray powder diffraction examinations revealed that the polar R3c phase in the Bi1−xRExFeO3 systems with RE = Er, Tm and Yb do not exceed 7, 4 and 3 mol.% of rare earth, respectively. Partial substitution of Er and Tm for the Bi sites in BiFeO3 reduce the temperature of the ferroelectric phase transition R3c-Pbnm on 30–60 K.
{"title":"Phase composition and crystal structure of the RE-substituted BiFeO3 (RE = Er, Tm, Yb)","authors":"O. Kuz, V. Handysh, Y. Prots, L. Vasylechko","doi":"10.1109/OMEE.2012.6464823","DOIUrl":"https://doi.org/10.1109/OMEE.2012.6464823","url":null,"abstract":"The work deals with the study of the phase and structural behaviour of the rare-earth substituted BiFeO<inf>3</inf>. X-ray powder diffraction examinations revealed that the polar R3c phase in the Bi<inf>1−x</inf>RE<inf>x</inf>FeO<inf>3</inf> systems with RE = Er, Tm and Yb do not exceed 7, 4 and 3 mol.% of rare earth, respectively. Partial substitution of Er and Tm for the Bi sites in BiFeO<inf>3</inf> reduce the temperature of the ferroelectric phase transition R3c-Pbnm on 30–60 K.","PeriodicalId":6332,"journal":{"name":"2012 IEEE International Conference on Oxide Materials for Electronic Engineering (OMEE)","volume":"171 1","pages":"118-119"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75696619","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：