Pub Date : 2002-11-01DOI: 10.1080/13642810208222941
M. Georgiev, N. Goutev, Z. Nickolov, J. Ramsden, G. Georgiev
Abstract Excess thermodynamic parameters of H2O water, corresponding to the difference between parameters for liquid water and ice, have been determined from the infrared O─H stretching spectra of very dilute solutions of HOD in D2O. The analytical method applied considers the H-bonded O─H oscillators as a statistical ensemble. Comparison of the results with reference calorimetric data for water showed good correspondence for the excess free energy, enthalpy and entropy of water. There is a discrepancy between our calculation and calorimetric data for the specific heat capacity of supercooled water. It is attributed to the inadequacy of the vibrationally decoupled spectra to describe collective structures in water and their dynamic fluctuations.
{"title":"Thermodynamic parameters of water calculated from its infrared OH stretching spectrum","authors":"M. Georgiev, N. Goutev, Z. Nickolov, J. Ramsden, G. Georgiev","doi":"10.1080/13642810208222941","DOIUrl":"https://doi.org/10.1080/13642810208222941","url":null,"abstract":"Abstract Excess thermodynamic parameters of H2O water, corresponding to the difference between parameters for liquid water and ice, have been determined from the infrared O─H stretching spectra of very dilute solutions of HOD in D2O. The analytical method applied considers the H-bonded O─H oscillators as a statistical ensemble. Comparison of the results with reference calorimetric data for water showed good correspondence for the excess free energy, enthalpy and entropy of water. There is a discrepancy between our calculation and calorimetric data for the specific heat capacity of supercooled water. It is attributed to the inadequacy of the vibrationally decoupled spectra to describe collective structures in water and their dynamic fluctuations.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89833602","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 : 2002-11-01DOI: 10.1080/13642810208223170
A. Bussmann-Holder, M. Gulácsi, A. Bishop
Abstract We study a model of a multiband Fermi-surface structure to investigate its effect on the superconducting transition temperature in the limit of a high number of bands. We consider a simple limit consisting of an infinite number of identical locally pairwise coupled bands with intraband and interband hopping and a multiband generalized Bardeen-Cooper-Schrieffer Hamiltonian. The self-consistent mean-field system of equations which determines the intraband and interband order parameters decouples to two independent equations, unless the interband hopping integral is non-zero, in which case an energetically stable superconducting phase appears, where both the intraband and the interband gaps are non-zero. We demonstrate that for all values of the interband coupling constant the critical transition temperature is enhanced compared with the pure intraband critical transition temperature. The model is equivalent to a multiple momentum exchange originating from the interband coupling and thus modelling a highly anisotropic gap structure.
{"title":"T c enhancement in multiphonon-mediated multiband superconductivity","authors":"A. Bussmann-Holder, M. Gulácsi, A. Bishop","doi":"10.1080/13642810208223170","DOIUrl":"https://doi.org/10.1080/13642810208223170","url":null,"abstract":"Abstract We study a model of a multiband Fermi-surface structure to investigate its effect on the superconducting transition temperature in the limit of a high number of bands. We consider a simple limit consisting of an infinite number of identical locally pairwise coupled bands with intraband and interband hopping and a multiband generalized Bardeen-Cooper-Schrieffer Hamiltonian. The self-consistent mean-field system of equations which determines the intraband and interband order parameters decouples to two independent equations, unless the interband hopping integral is non-zero, in which case an energetically stable superconducting phase appears, where both the intraband and the interband gaps are non-zero. We demonstrate that for all values of the interband coupling constant the critical transition temperature is enhanced compared with the pure intraband critical transition temperature. The model is equivalent to a multiple momentum exchange originating from the interband coupling and thus modelling a highly anisotropic gap structure.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89646560","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 : 2002-11-01DOI: 10.1080/13642810208222939
K. Ng, H. Kui
Abstract Nanostructured Pd82Si18 alloy rods of diameter 7 mm and length 77 mm can be synthesized by a process that employs liquid-phase spinodal decomposition. Micropores are not found in the transmission electron microscopy specimens, but there are surface grooves and/or internal cavities.
{"title":"Formation of large nanostructured Pd82Si18 alloy rods","authors":"K. Ng, H. Kui","doi":"10.1080/13642810208222939","DOIUrl":"https://doi.org/10.1080/13642810208222939","url":null,"abstract":"Abstract Nanostructured Pd82Si18 alloy rods of diameter 7 mm and length 77 mm can be synthesized by a process that employs liquid-phase spinodal decomposition. Micropores are not found in the transmission electron microscopy specimens, but there are surface grooves and/or internal cavities.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81437606","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 : 2002-11-01DOI: 10.1080/1364281021000050070
Yuxi Chen, J. Koike, T. Higuchi, S. Iwashita, M. Ishida, T. Shimoda
{"title":"Microstructure of epitaxial SrRuO 3 films on Si(001) substrates","authors":"Yuxi Chen, J. Koike, T. Higuchi, S. Iwashita, M. Ishida, T. Shimoda","doi":"10.1080/1364281021000050070","DOIUrl":"https://doi.org/10.1080/1364281021000050070","url":null,"abstract":"","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78709461","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 : 2002-11-01DOI: 10.1080/13642810208222938
A. Barnard, S. Russo, I. Snook
Abstract An analysis of the electronic properties of bulk cubic and hexagonal diamond calculated using the ab initio packages CRYSTAL98 and the Vienna Ab initio Simulation Package is presented. We apply these ab initio methods to the study of cubic diamond, including the calculation of electronic properties (such as the band structure, electronic density of states, the indirect bandgap E indirect g, the valence band width and the conduction band width) and mechanical properties (such as the equilibrium lattice constant a 0 and the bulk modulus B). The combination of theoretical techniques that yield results that most accurately match experiment for cubic diamond are then used to calculate the electronic properties of the hexagonal diamond polymorph.
{"title":"Comparative Hartree-Fock and density-functional theory study of cubic and hexagonal diamond","authors":"A. Barnard, S. Russo, I. Snook","doi":"10.1080/13642810208222938","DOIUrl":"https://doi.org/10.1080/13642810208222938","url":null,"abstract":"Abstract An analysis of the electronic properties of bulk cubic and hexagonal diamond calculated using the ab initio packages CRYSTAL98 and the Vienna Ab initio Simulation Package is presented. We apply these ab initio methods to the study of cubic diamond, including the calculation of electronic properties (such as the band structure, electronic density of states, the indirect bandgap E indirect g, the valence band width and the conduction band width) and mechanical properties (such as the equilibrium lattice constant a 0 and the bulk modulus B). The combination of theoretical techniques that yield results that most accurately match experiment for cubic diamond are then used to calculate the electronic properties of the hexagonal diamond polymorph.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76688658","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 : 2002-11-01DOI: 10.1080/13642810208223168
C. Colinet, A. Pasturel
Abstract The cohesive energies of L12, D022, D023 and selected one-dimensional (1D) long-period structures (LPSs) based on the L12 structure in the Ni-V system for the Ni3V composition have been obtained by ab-initio calculations using the Vienna ab-initio simulation package. Relaxations, both external and internal with respect to the cell, are taken into account in the determination of the structural stability of the 1D LPSs. At each stage of the relaxation process the D022 structure is the ground state. The values of the (001) antiphase-boundary (APB) energies are obtained from the energy differences of 1D LPSs with respect to either L12 or D022, with stacking of at least three L12 cubes along the direction perpendicular to the APB. The energy effects in the 1D LPSs are described in the framework of an axial next-nearest neighbour Ising model. The values of the interaction parameters are obtained in the ideal, distorted and fully relaxed structures. The APB energies are also derived from these parameters. The results show that it is necessary to consider long-range interactions in order to obtain reliable values of the APB energies. The results show also the influence of the relaxation effects on the APB energies.
{"title":"Ab initio determination of the (001) antiphase-boundary energy in the D022 Ni3V compound","authors":"C. Colinet, A. Pasturel","doi":"10.1080/13642810208223168","DOIUrl":"https://doi.org/10.1080/13642810208223168","url":null,"abstract":"Abstract The cohesive energies of L12, D022, D023 and selected one-dimensional (1D) long-period structures (LPSs) based on the L12 structure in the Ni-V system for the Ni3V composition have been obtained by ab-initio calculations using the Vienna ab-initio simulation package. Relaxations, both external and internal with respect to the cell, are taken into account in the determination of the structural stability of the 1D LPSs. At each stage of the relaxation process the D022 structure is the ground state. The values of the (001) antiphase-boundary (APB) energies are obtained from the energy differences of 1D LPSs with respect to either L12 or D022, with stacking of at least three L12 cubes along the direction perpendicular to the APB. The energy effects in the 1D LPSs are described in the framework of an axial next-nearest neighbour Ising model. The values of the interaction parameters are obtained in the ideal, distorted and fully relaxed structures. The APB energies are also derived from these parameters. The results show that it is necessary to consider long-range interactions in order to obtain reliable values of the APB energies. The results show also the influence of the relaxation effects on the APB energies.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91482819","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 : 2002-11-01DOI: 10.1080/13642810208222937
W. Harrison
Abstract We study the energy gained for simple crystal structures by occupying the lower portion of tight-binding bands arising from one shell of atomic orbitals. We see that a Friedel model, based upon a rectangular density of states and the second moment of the bands, gives a reasonable account of the cohesive energy. It also predicts an equilibrium spacing proportional to the fourth root of the coordination but gives total energies independent of coordination. This depended upon an interatomic repulsion assumed to be proportional to the square of the interorbital coupling. When the variation in the repulsion is more rapid, as it tends to be lower in the periodic table, and in the simple metals, larger coordinations and simple close-packed structures are favoured. Going beyond this approximation, we find the energy lower when weakly coupled bond orbitals can be constructed, as for the [sgrave] bonds in tetrahedral semiconductors. Applying this correction to half-filled p bands favours the formation of right-angle [sgrave] bonds between three neighbours. This result, modified for the different filling of the p shell in the non-metal groups V, VI, VII and VIII of the periodic table, gives a good qualitative account of the observed structures. The same theory applied to half-filled f bands gives the same tendency for right-angle [sgrave] bonds, although for d bands it does not. Applying the theory to the light actinides, for fillings less than half, makes plausible the type of structures observed in plutonium and neptunium and is not inconsistent with those observed in uranium, protactinium and thorium.
{"title":"p, d and f bonds in elemental solids","authors":"W. Harrison","doi":"10.1080/13642810208222937","DOIUrl":"https://doi.org/10.1080/13642810208222937","url":null,"abstract":"Abstract We study the energy gained for simple crystal structures by occupying the lower portion of tight-binding bands arising from one shell of atomic orbitals. We see that a Friedel model, based upon a rectangular density of states and the second moment of the bands, gives a reasonable account of the cohesive energy. It also predicts an equilibrium spacing proportional to the fourth root of the coordination but gives total energies independent of coordination. This depended upon an interatomic repulsion assumed to be proportional to the square of the interorbital coupling. When the variation in the repulsion is more rapid, as it tends to be lower in the periodic table, and in the simple metals, larger coordinations and simple close-packed structures are favoured. Going beyond this approximation, we find the energy lower when weakly coupled bond orbitals can be constructed, as for the [sgrave] bonds in tetrahedral semiconductors. Applying this correction to half-filled p bands favours the formation of right-angle [sgrave] bonds between three neighbours. This result, modified for the different filling of the p shell in the non-metal groups V, VI, VII and VIII of the periodic table, gives a good qualitative account of the observed structures. The same theory applied to half-filled f bands gives the same tendency for right-angle [sgrave] bonds, although for d bands it does not. Applying the theory to the light actinides, for fillings less than half, makes plausible the type of structures observed in plutonium and neptunium and is not inconsistent with those observed in uranium, protactinium and thorium.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86325433","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 : 2002-11-01DOI: 10.1080/13642810208222942
A. Towner, M. Nathwani, A. Saleh, D. P. van der Werf, P. Rice-Evans
Abstract Positron annihilation spectroscopy has been applied to silicon-doped GaAs grown by molecular-beam epitaxy. Annealing SiO2 capped samples at 930°C causes the SiGa—VGa vacancies to become positively charged. The SiO2 caps cause oxygen to diffuse beneath the surface and the spectroscopy leads to the first measurement of the oxygen diffusion coefficient in GaAs. The application of a new analysis program ROYPROF reveals the creation of internal electric fields.
{"title":"Positron annihilation study of the diffusion of oxygen in annealed silicon-doped gallium arsenide","authors":"A. Towner, M. Nathwani, A. Saleh, D. P. van der Werf, P. Rice-Evans","doi":"10.1080/13642810208222942","DOIUrl":"https://doi.org/10.1080/13642810208222942","url":null,"abstract":"Abstract Positron annihilation spectroscopy has been applied to silicon-doped GaAs grown by molecular-beam epitaxy. Annealing SiO2 capped samples at 930°C causes the SiGa—VGa vacancies to become positively charged. The SiO2 caps cause oxygen to diffuse beneath the surface and the spectroscopy leads to the first measurement of the oxygen diffusion coefficient in GaAs. The application of a new analysis program ROYPROF reveals the creation of internal electric fields.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89302736","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 : 2002-11-01DOI: 10.1080/13642810208222940
P. Fojtík, K. Dohnalová, T. Mates, J. Stuchlík, I. Gregora, J. Chval, A. Fejfar, J. Kǒcka, I. Pelant
Abstract A way in which thin films of hydrogenated amorphous silicon (a-Si: H) can be instantaneously crystallized at room temperature is reported. The metal-induced solid-phase crystallization (MISPC) method with nickel surface coverage is used. In comparison with previous reports on the MISPC of a-Si: H, the crystallization temperature is reduced by more than 350°C. This is achieved by introducing two novel technological steps: firstly, we use hydrogen-rich a-Si: H films (hydrogen content between 20 and 45at.% H) and, secondly, we apply a high transverse electric field. Polycrystalline silicon islands as large as 3 mm across appear instantaneously after having reached a threshold electric field of about 105Vcm−1. We report macroscopic visualization of the crystallization process as well as microscopic investigation (micro-Raman measurements and scanning electron microphotography) of the crystallized films. We have found that appropriate patterning of the nickel electrode helps to increase homogeneity of the resulting polycrystalline silicon.
{"title":"Rapid crystallization of amorphous silicon at room temperature","authors":"P. Fojtík, K. Dohnalová, T. Mates, J. Stuchlík, I. Gregora, J. Chval, A. Fejfar, J. Kǒcka, I. Pelant","doi":"10.1080/13642810208222940","DOIUrl":"https://doi.org/10.1080/13642810208222940","url":null,"abstract":"Abstract A way in which thin films of hydrogenated amorphous silicon (a-Si: H) can be instantaneously crystallized at room temperature is reported. The metal-induced solid-phase crystallization (MISPC) method with nickel surface coverage is used. In comparison with previous reports on the MISPC of a-Si: H, the crystallization temperature is reduced by more than 350°C. This is achieved by introducing two novel technological steps: firstly, we use hydrogen-rich a-Si: H films (hydrogen content between 20 and 45at.% H) and, secondly, we apply a high transverse electric field. Polycrystalline silicon islands as large as 3 mm across appear instantaneously after having reached a threshold electric field of about 105Vcm−1. We report macroscopic visualization of the crystallization process as well as microscopic investigation (micro-Raman measurements and scanning electron microphotography) of the crystallized films. We have found that appropriate patterning of the nickel electrode helps to increase homogeneity of the resulting polycrystalline silicon.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83705326","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 : 2002-10-01DOI: 10.1080/13642810208220733
S. Nagata, Seiji Ito, R. Endoh, J. Awaka
Abstract The normal sulphospinel CuIr2S4 exhibits a temperature-induced metalinsulator (M-I) transition around T M-1 = 230 K with a structural transformation. This T M-1 increases markedly with increasing pressure. It has been verified that the 5d electrons of Ir ions at the B sites located at the Fermi surface play a significant role for the strong correlated electron system. Conversely, CuTi2S4 remains metallic down to 4.2 K without any structural transformations. These two compounds have the same normal spinel structure, whereas the number of d electrons at the B sites are quite different. High-purity spinel-type Cu(Iri1−xTix)2S4 specimens have been successfully synthesized. The value of the lattice constant a indicates a broad minimum around x = 0.12, not obeying Vegard's law. We have systematically studied the structural transformation and electrical and magnetic properties of Cu(Ir1−xTix)2S4. A phase diagram between T M-1 and x will be provided for the Cu(Ir1−xTix)2S4 system. T M-1 varies drastically with x and disappears at around x = 0.06. A novel relationship, namely a ‘mirror image effect’, between the value of residual resistivity and the magnitude of the electronic density of states, D(εF), at the Fermi level, has been observed accurately.
{"title":"Metal–insulator transition in the spinel-type Cu (Ir1–xTix)2S4 system","authors":"S. Nagata, Seiji Ito, R. Endoh, J. Awaka","doi":"10.1080/13642810208220733","DOIUrl":"https://doi.org/10.1080/13642810208220733","url":null,"abstract":"Abstract The normal sulphospinel CuIr2S4 exhibits a temperature-induced metalinsulator (M-I) transition around T M-1 = 230 K with a structural transformation. This T M-1 increases markedly with increasing pressure. It has been verified that the 5d electrons of Ir ions at the B sites located at the Fermi surface play a significant role for the strong correlated electron system. Conversely, CuTi2S4 remains metallic down to 4.2 K without any structural transformations. These two compounds have the same normal spinel structure, whereas the number of d electrons at the B sites are quite different. High-purity spinel-type Cu(Iri1−xTix)2S4 specimens have been successfully synthesized. The value of the lattice constant a indicates a broad minimum around x = 0.12, not obeying Vegard's law. We have systematically studied the structural transformation and electrical and magnetic properties of Cu(Ir1−xTix)2S4. A phase diagram between T M-1 and x will be provided for the Cu(Ir1−xTix)2S4 system. T M-1 varies drastically with x and disappears at around x = 0.06. A novel relationship, namely a ‘mirror image effect’, between the value of residual resistivity and the magnitude of the electronic density of states, D(εF), at the Fermi level, has been observed accurately.","PeriodicalId":20016,"journal":{"name":"Philosophical Magazine Part B","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88094390","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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