Pub Date : 2001-03-01DOI: 10.1556/APH.13.2001.1-3.22
G. Filippov, Yu. A. Lashko
Photodisintegration of 11Li and radiation capture of two neutrons by 9Li are studied in the frame of algebraic version of resonating group method and in asymptotic potential approximation. The behavior of the scattering phases shows on the existence of Jπ=3/2+ and Jπ=5/2+ resonances in continuum above the three-body decay threshold 11Li→9Li+n + n. The cross-section of photodisintegration as well as the cross-section of radiation capture have been received. Energetic dependence of the first one is in good correspondence with the experimental data.
{"title":"Photodisintegration of 11 Li and Radiation Capture of Two Neutrons by 9 Li","authors":"G. Filippov, Yu. A. Lashko","doi":"10.1556/APH.13.2001.1-3.22","DOIUrl":"https://doi.org/10.1556/APH.13.2001.1-3.22","url":null,"abstract":"Photodisintegration of 11Li and radiation capture of two neutrons by 9Li are studied in the frame of algebraic version of resonating group method and in asymptotic potential approximation. The behavior of the scattering phases shows on the existence of Jπ=3/2+ and Jπ=5/2+ resonances in continuum above the three-body decay threshold 11Li→9Li+n + n. The cross-section of photodisintegration as well as the cross-section of radiation capture have been received. Energetic dependence of the first one is in good correspondence with the experimental data.","PeriodicalId":7004,"journal":{"name":"Acta Physica Hungarica","volume":"1 1","pages":"175-178"},"PeriodicalIF":0.0,"publicationDate":"2001-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76941946","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 : 2001-03-01DOI: 10.1556/APH.13.2001.1-3.7
F. Hartmann, R. Schmidt, T. Egidy, J. Jastrzȩbski, P. Lubiński, L. Pieńkowski, A. Trzcińska, R. Smolańczuk, S. Wycech, B. Kłos
In the experiments of the PS209 collaboration at the Low Energy Antiproton Ring LEAR at CERN two methods were applied to study the nuclear periphery: first the yields of residual nuclei with mass number A — 1 were determined with radiochemical methods, and secondly the widths and shifts of the last observable transitions in antiprotonic atoms were measured with Ge detectors. The ratio of yields after annihilation for nuclei with one neutron missing to those with one proton missing from the target nucleus was found to depend strongly on the binding energy of the most loosely bound neutron of the target nucleus. The values were in astonishingly good agreement with a rather simple model for the proton and neutron density distribution devised by Gambhir et al. Furthermore the normalized yield ratio stays constant up to a relative neutron excess of about 0.15 and afterwards rises steeply. Widths for in total 62 x-ray Unes from antiprotonic atoms were compared with the results of calculations of Batty et al. The agreement is reasonable on a semiquantitative basis, but improvements are desirable. For a number of nuclei the differences between the diffuseness values for the proton and neutron distributions were determined directly from the x-ray-line intensity and width data. The root-mean-square radii for the neutron and proton distributions may be derived from these results. The experimental data for four tin isotopes are in reasonable agreement with the experiments of Krasznahorkay et al., but lower than theory predicts.
{"title":"Study of the nuclear periphery with Antiprotons","authors":"F. Hartmann, R. Schmidt, T. Egidy, J. Jastrzȩbski, P. Lubiński, L. Pieńkowski, A. Trzcińska, R. Smolańczuk, S. Wycech, B. Kłos","doi":"10.1556/APH.13.2001.1-3.7","DOIUrl":"https://doi.org/10.1556/APH.13.2001.1-3.7","url":null,"abstract":"In the experiments of the PS209 collaboration at the Low Energy Antiproton Ring LEAR at CERN two methods were applied to study the nuclear periphery: first the yields of residual nuclei with mass number A — 1 were determined with radiochemical methods, and secondly the widths and shifts of the last observable transitions in antiprotonic atoms were measured with Ge detectors. The ratio of yields after annihilation for nuclei with one neutron missing to those with one proton missing from the target nucleus was found to depend strongly on the binding energy of the most loosely bound neutron of the target nucleus. The values were in astonishingly good agreement with a rather simple model for the proton and neutron density distribution devised by Gambhir et al. Furthermore the normalized yield ratio stays constant up to a relative neutron excess of about 0.15 and afterwards rises steeply. Widths for in total 62 x-ray Unes from antiprotonic atoms were compared with the results of calculations of Batty et al. The agreement is reasonable on a semiquantitative basis, but improvements are desirable. For a number of nuclei the differences between the diffuseness values for the proton and neutron distributions were determined directly from the x-ray-line intensity and width data. The root-mean-square radii for the neutron and proton distributions may be derived from these results. The experimental data for four tin isotopes are in reasonable agreement with the experiments of Krasznahorkay et al., but lower than theory predicts.","PeriodicalId":7004,"journal":{"name":"Acta Physica Hungarica","volume":"16 1","pages":"51-60"},"PeriodicalIF":0.0,"publicationDate":"2001-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89056232","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 : 2001-03-01DOI: 10.1556/APH.13.2001.1-3.9
D. Poenaru, B. Dobrescu, W. Greiner, J. Hamilton, A. Ramayya
A three-center phenomenological model, able to explain qualitatively the recently obtained experimental results concerning the quasimolecu-lar stage of a light-particle accompanied fission process is presented. It was derived from the liquid drop model under the assumption that the aligned configuration, with the emitted particle between the light and heavy fragment, is reached by increasing continuously the separation distance, while the radii of the heavy fragment and of the light particle are kept constant. In such a way, a new minimum appears in the deformation energy at a separation distance very close to the touching point. This minimum allows the existence of a short-lived quasi-molecular state, decaying into the three final fragments. The influence of the shell effects is discussed. The half-lives of some quasimolecular states which could be formed in the 10Be and 12C accompanied fission of 252Cf are roughly estimated to be of the order of 1 ns and 1 ms, respectively.
{"title":"Fission Energy Surfaces and Ternary Fission","authors":"D. Poenaru, B. Dobrescu, W. Greiner, J. Hamilton, A. Ramayya","doi":"10.1556/APH.13.2001.1-3.9","DOIUrl":"https://doi.org/10.1556/APH.13.2001.1-3.9","url":null,"abstract":"A three-center phenomenological model, able to explain qualitatively the recently obtained experimental results concerning the quasimolecu-lar stage of a light-particle accompanied fission process is presented. It was derived from the liquid drop model under the assumption that the aligned configuration, with the emitted particle between the light and heavy fragment, is reached by increasing continuously the separation distance, while the radii of the heavy fragment and of the light particle are kept constant. In such a way, a new minimum appears in the deformation energy at a separation distance very close to the touching point. This minimum allows the existence of a short-lived quasi-molecular state, decaying into the three final fragments. The influence of the shell effects is discussed. The half-lives of some quasimolecular states which could be formed in the 10Be and 12C accompanied fission of 252Cf are roughly estimated to be of the order of 1 ns and 1 ms, respectively.","PeriodicalId":7004,"journal":{"name":"Acta Physica Hungarica","volume":"5 1","pages":"79-88"},"PeriodicalIF":0.0,"publicationDate":"2001-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87618040","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 : 2001-03-01DOI: 10.1556/APH.13.2001.1-3.29
M. Csatlós, A. Krasznahorkay, van den Ad M Berg, M. Harakeh, S. Y. Werf, M. Hagemann, M. D. Huu, H. Akimune, H. Fujimura, M. Fujiwara, K. Hara, T. Ishikawa
Dipole resonances have been excited in Sn112-124 isotopes using (He-3,t) charge exchange reaction at E-3He = 177 MeV and the cross sections were related to the neutron-skin thicknesses. The well understood correlation may be used to determine the neutron-skin thicknesses in the future.
{"title":"A new method to measure the neutron skin","authors":"M. Csatlós, A. Krasznahorkay, van den Ad M Berg, M. Harakeh, S. Y. Werf, M. Hagemann, M. D. Huu, H. Akimune, H. Fujimura, M. Fujiwara, K. Hara, T. Ishikawa","doi":"10.1556/APH.13.2001.1-3.29","DOIUrl":"https://doi.org/10.1556/APH.13.2001.1-3.29","url":null,"abstract":"Dipole resonances have been excited in Sn112-124 isotopes using (He-3,t) charge exchange reaction at E-3He = 177 MeV and the cross sections were related to the neutron-skin thicknesses. The well understood correlation may be used to determine the neutron-skin thicknesses in the future.","PeriodicalId":7004,"journal":{"name":"Acta Physica Hungarica","volume":"32 1","pages":"203-205"},"PeriodicalIF":0.0,"publicationDate":"2001-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85302266","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 : 2001-03-01DOI: 10.1556/APH.13.2001.1-3.26
A. Pasternak, J. Srebrny, C. Droste, T. Morek
The modified procedure of RDM and DSAM data analysis applied to lifetime measurements in 119I presented. The main points are: the Recoil Distance Doppler Shift Attenuation Method, the evaluation of side-feeding time, and self-calibration of stopping-power parameters by “semi-thick” target method.
{"title":"New approach to doppler lifetime measurements","authors":"A. Pasternak, J. Srebrny, C. Droste, T. Morek","doi":"10.1556/APH.13.2001.1-3.26","DOIUrl":"https://doi.org/10.1556/APH.13.2001.1-3.26","url":null,"abstract":"The modified procedure of RDM and DSAM data analysis applied to lifetime measurements in 119I presented. The main points are: the Recoil Distance Doppler Shift Attenuation Method, the evaluation of side-feeding time, and self-calibration of stopping-power parameters by “semi-thick” target method.","PeriodicalId":7004,"journal":{"name":"Acta Physica Hungarica","volume":"35 1","pages":"193-196"},"PeriodicalIF":0.0,"publicationDate":"2001-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85303863","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 : 2001-03-01DOI: 10.1556/APH.13.2001.1-3.11
P. Thirolf, D. Gassmann, D. Habs, M. Chromik, Y. Eisermann, G. Graw, R. Hertenberger, H. Maier, A. Metz, P. Reiter, T. Faestermann, A. Krasznahorkay, M. Hunyadi, M. Csatlós, J. Gulyás, Z. Máté, D. Pansegrau, H. Scheit, D. Schwalm, E. Mergel, H. Hübel, A. Görgen
Spectroscopic studies in the superdeformed shape isomer of 240Pu using γ-spectroscopy, conversion electron spectroscopy and transmission resonance spectroscopy have been performed. In a high-resolution and high-efficiency γ-spectroscopy experiment the out-of-band decays of several excited superdeformed rotational sequences with K=2− and 1− could be identified together with evidence for a weakly populated 0− octupole band. Surprisingly, no low-lying collective quadrupole excitations could be observed. Complementary information could be obtained in conversion electron measurements in coincidence with isomeric fission, resulting in the first identification of the lowest s-vibrational K=0+ band. For all rotational bands the variation of the moment of inertia with spin could be studied. A predominant population of negative parity states in the second well could be observed, which can be explained by the selective population and depopulation of the second minimum. Complementary transmission resonance measurements have been performed, yielding new information on the fine structure of high-lying (s-)vibrational multi-phonon states. A new method could be established to determine the excitation energy of the fission isomer ground state from measured level densities.
{"title":"Detailed spectroscopy in the superdeformed second minimum of 240 Pu","authors":"P. Thirolf, D. Gassmann, D. Habs, M. Chromik, Y. Eisermann, G. Graw, R. Hertenberger, H. Maier, A. Metz, P. Reiter, T. Faestermann, A. Krasznahorkay, M. Hunyadi, M. Csatlós, J. Gulyás, Z. Máté, D. Pansegrau, H. Scheit, D. Schwalm, E. Mergel, H. Hübel, A. Görgen","doi":"10.1556/APH.13.2001.1-3.11","DOIUrl":"https://doi.org/10.1556/APH.13.2001.1-3.11","url":null,"abstract":"Spectroscopic studies in the superdeformed shape isomer of 240Pu using γ-spectroscopy, conversion electron spectroscopy and transmission resonance spectroscopy have been performed. In a high-resolution and high-efficiency γ-spectroscopy experiment the out-of-band decays of several excited superdeformed rotational sequences with K=2− and 1− could be identified together with evidence for a weakly populated 0− octupole band. Surprisingly, no low-lying collective quadrupole excitations could be observed. Complementary information could be obtained in conversion electron measurements in coincidence with isomeric fission, resulting in the first identification of the lowest s-vibrational K=0+ band. For all rotational bands the variation of the moment of inertia with spin could be studied. A predominant population of negative parity states in the second well could be observed, which can be explained by the selective population and depopulation of the second minimum. Complementary transmission resonance measurements have been performed, yielding new information on the fine structure of high-lying (s-)vibrational multi-phonon states. A new method could be established to determine the excitation energy of the fission isomer ground state from measured level densities.","PeriodicalId":7004,"journal":{"name":"Acta Physica Hungarica","volume":"22 1","pages":"93-110"},"PeriodicalIF":0.0,"publicationDate":"2001-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85182453","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 : 2001-03-01DOI: 10.1556/APH.13.2001.1-3.10
R. Bijker, P. Hess, Ş. Mişicu
A geometrical model for tri-nuclear molecules is reviewed. For an analytical solution the nuclei have to be prolately deformed and in a line connected to each other. Furthermore, there have to be two heavy and one light cluster, the latter sandwiched between the two heavy clusters. As an alternative we also study an algebraic model of tri-cluster molecules based on a U(7) group. This model allows arbitrary orientations of the center of masses.
{"title":"A geometric and an algebraic model for tri-nuclear molecules","authors":"R. Bijker, P. Hess, Ş. Mişicu","doi":"10.1556/APH.13.2001.1-3.10","DOIUrl":"https://doi.org/10.1556/APH.13.2001.1-3.10","url":null,"abstract":"A geometrical model for tri-nuclear molecules is reviewed. For an analytical solution the nuclei have to be prolately deformed and in a line connected to each other. Furthermore, there have to be two heavy and one light cluster, the latter sandwiched between the two heavy clusters. As an alternative we also study an algebraic model of tri-cluster molecules based on a U(7) group. This model allows arbitrary orientations of the center of masses.","PeriodicalId":7004,"journal":{"name":"Acta Physica Hungarica","volume":" 32","pages":"89-92"},"PeriodicalIF":0.0,"publicationDate":"2001-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91412900","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 : 2001-03-01DOI: 10.1556/APH.13.2001.1-3.24
I. Diószegi, I. Mazumdar, P. Paul
In a detailed investigation of giant dipole resonance (GDR) γ-ray yield from 240Cf populated in the 32S + 208Pb reaction, the absolute γ-ray/fission multiplicities are extracted over a wide range of excitation energy and angular momentum. The enhanced yield of GDR decay γ rays has been analyzed within the framework of a modified statistical model containing the nuclear viscosity as a free parameter. The extracted nuclear dissipation coefficient is found to be independent of the temperature. Large constant dissipation during the saddle-to-scission path provides good fits to the γ-ray spectra.
{"title":"Nuclear viscosity of hot rotating 240 Cf","authors":"I. Diószegi, I. Mazumdar, P. Paul","doi":"10.1556/APH.13.2001.1-3.24","DOIUrl":"https://doi.org/10.1556/APH.13.2001.1-3.24","url":null,"abstract":"In a detailed investigation of giant dipole resonance (GDR) γ-ray yield from 240Cf populated in the 32S + 208Pb reaction, the absolute γ-ray/fission multiplicities are extracted over a wide range of excitation energy and angular momentum. The enhanced yield of GDR decay γ rays has been analyzed within the framework of a modified statistical model containing the nuclear viscosity as a free parameter. The extracted nuclear dissipation coefficient is found to be independent of the temperature. Large constant dissipation during the saddle-to-scission path provides good fits to the γ-ray spectra.","PeriodicalId":7004,"journal":{"name":"Acta Physica Hungarica","volume":"348 1","pages":"185-188"},"PeriodicalIF":0.0,"publicationDate":"2001-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82582756","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 : 2001-03-01DOI: 10.1556/APH.13.2001.1-3.28
E. Mergel, G. Schönwaβer, H. Hübel, D. Roβbach, P. Thirolf, M. Chromik, D. Gassmann, D. Habs, P. Reiter
Transitions between nuclear states with a large deformation difference may have large transition probabilities for E0 decay. Such an E0 decay has been found in the decay of the superdeformed 238U fission isomer back into the normal-deformed states [1]. However, a search for the E0 back-decay in 236U showed no result [2]. A setup has been developed to search for conversion electrons in this decay.
{"title":"A setup for the search for E0 decay of superdeformed 236 U","authors":"E. Mergel, G. Schönwaβer, H. Hübel, D. Roβbach, P. Thirolf, M. Chromik, D. Gassmann, D. Habs, P. Reiter","doi":"10.1556/APH.13.2001.1-3.28","DOIUrl":"https://doi.org/10.1556/APH.13.2001.1-3.28","url":null,"abstract":"Transitions between nuclear states with a large deformation difference may have large transition probabilities for E0 decay. Such an E0 decay has been found in the decay of the superdeformed 238U fission isomer back into the normal-deformed states [1]. However, a search for the E0 back-decay in 236U showed no result [2]. A setup has been developed to search for conversion electrons in this decay.","PeriodicalId":7004,"journal":{"name":"Acta Physica Hungarica","volume":"92 1","pages":"199-202"},"PeriodicalIF":0.0,"publicationDate":"2001-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74003400","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 : 2001-03-01DOI: 10.1556/APH.13.2001.1-3.12
A. Krasznahorkay, D. Habs, M. Hunyadi, D. Gassmann, M. Csatlós, Y. Eisermann, T. Faestermann, G. Graw, J. Gulyás, R. Hertenberger, H. Maier, Z. Máté, A. Metz, J. Ott, P. Thirolf, S. Y. Werf
The 233U(d,pf)234U, and the 235U(d,pf)236U reactions have been studied with high energy resolution. The observed fission resonances were described as members of rotational bands with rotational parameters characteristic of hyperdeformed nuclear shapes. Information on the K values of the bands and for the J values of the band members has been obtained from fission fragment angular distribution measurements. The level density of the most strongly excited states has been compared to the prediction of the back-shifted Fermi-gas formula and the energy of the ground state in the third minimum has been estimated for 234U. The fission fragment mass distribution of the hyperdeformed states in 236U has also been measured. The width of the mass distribution, coincident with the hyperdeformed bands, is significantly smaller than the ones obtained in coincidence with background regions below and above the resonances, which suggests a pear-shaped di-nuclear configuration of 236U in the third well of the potential barrier.
{"title":"Hyperdeformation and clusterization in the actinide region","authors":"A. Krasznahorkay, D. Habs, M. Hunyadi, D. Gassmann, M. Csatlós, Y. Eisermann, T. Faestermann, G. Graw, J. Gulyás, R. Hertenberger, H. Maier, Z. Máté, A. Metz, J. Ott, P. Thirolf, S. Y. Werf","doi":"10.1556/APH.13.2001.1-3.12","DOIUrl":"https://doi.org/10.1556/APH.13.2001.1-3.12","url":null,"abstract":"The 233U(d,pf)234U, and the 235U(d,pf)236U reactions have been studied with high energy resolution. The observed fission resonances were described as members of rotational bands with rotational parameters characteristic of hyperdeformed nuclear shapes. Information on the K values of the bands and for the J values of the band members has been obtained from fission fragment angular distribution measurements. The level density of the most strongly excited states has been compared to the prediction of the back-shifted Fermi-gas formula and the energy of the ground state in the third minimum has been estimated for 234U. The fission fragment mass distribution of the hyperdeformed states in 236U has also been measured. The width of the mass distribution, coincident with the hyperdeformed bands, is significantly smaller than the ones obtained in coincidence with background regions below and above the resonances, which suggests a pear-shaped di-nuclear configuration of 236U in the third well of the potential barrier.","PeriodicalId":7004,"journal":{"name":"Acta Physica Hungarica","volume":"10 1","pages":"111-120"},"PeriodicalIF":0.0,"publicationDate":"2001-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88625228","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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