This paper discusses the heterogeneous nucleation of solidification, treating the fundamental process as taking place by adsorption on the surface of the heterogeneous nucleant. A theoretical framework for adsorption and nucleation catalysis is described, and some related experimental results are discussed.
{"title":"Heterogeneous nucleation and adsorption","authors":"B. Cantor","doi":"10.1098/rsta.2002.1137","DOIUrl":"https://doi.org/10.1098/rsta.2002.1137","url":null,"abstract":"This paper discusses the heterogeneous nucleation of solidification, treating the fundamental process as taking place by adsorption on the surface of the heterogeneous nucleant. A theoretical framework for adsorption and nucleation catalysis is described, and some related experimental results are discussed.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84834738","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}
Glass ceramics are advanced materials composed of one or more glass and crystal phases. By developing base glasses with appropriate compositions and by controlling crystal nucleation and growth in these glasses, glass ceramics with tailor–made properties can be fabricated. The key to developing this type of material is control of the nucleation processes. Both volume and surface nucleation can be exploited. Heterogeneous volume nucleation has been used to develop glass ceramics showing minimal thermal expansion and high strength. Two nucleation mechanisms can be combined and the precipitation of two crystal phases can be controlled. That the nucleation processes can be controlled by nano– and microscale immiscibility is a special feature, allowing selective nanophase formation or the development of needle–like apatite phases demonstrating a natural morphology. This represents a biomimetic process. The control of nucleation has enabled the development of biomaterials for dental applications.
{"title":"Control of nucleation in glass ceramics","authors":"W. Höland, V. Rheinberger, M. Schweiger","doi":"10.1098/rsta.2002.1152","DOIUrl":"https://doi.org/10.1098/rsta.2002.1152","url":null,"abstract":"Glass ceramics are advanced materials composed of one or more glass and crystal phases. By developing base glasses with appropriate compositions and by controlling crystal nucleation and growth in these glasses, glass ceramics with tailor–made properties can be fabricated. The key to developing this type of material is control of the nucleation processes. Both volume and surface nucleation can be exploited. Heterogeneous volume nucleation has been used to develop glass ceramics showing minimal thermal expansion and high strength. Two nucleation mechanisms can be combined and the precipitation of two crystal phases can be controlled. That the nucleation processes can be controlled by nano– and microscale immiscibility is a special feature, allowing selective nanophase formation or the development of needle–like apatite phases demonstrating a natural morphology. This represents a biomimetic process. The control of nucleation has enabled the development of biomaterials for dental applications.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80838460","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}
Different maxima in the Leonid activity observed in the same year can be identified as due to dust particles ejected during different perihelion passages of the parent comet, 55P/Tempel–Tuttle. This is because the ecliptic intersections of trajectories of particles that were ejected during different comet apparitions lie well separated in the ecliptic plane. For November 2001, we determine the ecliptic intersection points of particles originating from various apparitions of 55P/Tempel–Tuttle and thus predict the times of maximum Leonid activity. By comparing this year's configuration with the past, we also give an estimate of the flux that might be expected in 2001. As light flashes due to Leonid impacts on the Moon can be detected on Earth, we give the times of closest approaches of dust trails to the Moon. By comparing the predicted Leonid meteoroid flux on the Earth's atmosphere with the flux of sporadic meteoroids, we estimate that the hazard of a Leonid impact on a spacecraft in low–Earth orbit is low. However, the densest part of the Leonid trails will not reach Earth, but will cross the geo–stationary orbit (GEO) ring. The impact risk will reach its maximum for GEO satellites at longitudes between 35° and 160° W between 17.00 and 20.00 UT on 18 November 2001. While the overall risk of major damage is still relatively low, this period undoubtedly represents the greatest impact risk to spacecraft since the beginning of the space–age.
{"title":"Prediction of the 2001 Leonid activity and an assessment of the spacecraft impact hazard","authors":"Michael Müller, N. Mcbride, S. Green, J. Zarnecki","doi":"10.1098/rsta.2002.1120","DOIUrl":"https://doi.org/10.1098/rsta.2002.1120","url":null,"abstract":"Different maxima in the Leonid activity observed in the same year can be identified as due to dust particles ejected during different perihelion passages of the parent comet, 55P/Tempel–Tuttle. This is because the ecliptic intersections of trajectories of particles that were ejected during different comet apparitions lie well separated in the ecliptic plane. For November 2001, we determine the ecliptic intersection points of particles originating from various apparitions of 55P/Tempel–Tuttle and thus predict the times of maximum Leonid activity. By comparing this year's configuration with the past, we also give an estimate of the flux that might be expected in 2001. As light flashes due to Leonid impacts on the Moon can be detected on Earth, we give the times of closest approaches of dust trails to the Moon. By comparing the predicted Leonid meteoroid flux on the Earth's atmosphere with the flux of sporadic meteoroids, we estimate that the hazard of a Leonid impact on a spacecraft in low–Earth orbit is low. However, the densest part of the Leonid trails will not reach Earth, but will cross the geo–stationary orbit (GEO) ring. The impact risk will reach its maximum for GEO satellites at longitudes between 35° and 160° W between 17.00 and 20.00 UT on 18 November 2001. While the overall risk of major damage is still relatively low, this period undoubtedly represents the greatest impact risk to spacecraft since the beginning of the space–age.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79919304","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}
A clear distinction is usually appropriate between the technologies and development processes for space–borne and ground–based functions. Limitations in the performance of space–borne computing, storage and dissemination facilities often preclude the use of non–space software technology. The key to affordability is the creation of international standards so that despite relatively high development costs, solutions can be reused across many missions and organizations. By contrast, ground–based functions can benefit from products developed for non–space applications. The challenge is to create an architecture that benefits from existing technology and meets the mission requirements. Optimizing the organizational arrangements for space missions is perhaps where the greatest savings can be made. A management structure that ensures that end users dominate the establishment of requirements leads to more affordable missions than one that is, say, technology driven. Industry implementation teams must include expertise in the scientific disciplines and mission objectives to ensure success. Geostationary–weather–satellite, space–science and satellite–navigation missions are used to illustrate these issues.
{"title":"Autonomy, control, processing and dissemination: getting data to the scientists, affordably","authors":"P. Norris","doi":"10.1098/rsta.2002.1121","DOIUrl":"https://doi.org/10.1098/rsta.2002.1121","url":null,"abstract":"A clear distinction is usually appropriate between the technologies and development processes for space–borne and ground–based functions. Limitations in the performance of space–borne computing, storage and dissemination facilities often preclude the use of non–space software technology. The key to affordability is the creation of international standards so that despite relatively high development costs, solutions can be reused across many missions and organizations. By contrast, ground–based functions can benefit from products developed for non–space applications. The challenge is to create an architecture that benefits from existing technology and meets the mission requirements. Optimizing the organizational arrangements for space missions is perhaps where the greatest savings can be made. A management structure that ensures that end users dominate the establishment of requirements leads to more affordable missions than one that is, say, technology driven. Industry implementation teams must include expertise in the scientific disciplines and mission objectives to ensure success. Geostationary–weather–satellite, space–science and satellite–navigation missions are used to illustrate these issues.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79712760","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}
The man–made orbital debris population is growing rapidly, dominating the meteoroid environment in all but the micrometre size range. Of most concern are objects between 1 cm and 10 cm, referred to as the lethal population as they cannot be tracked or catalogued and can cause catastrophic damage when colliding with a satellite. In order to address this problem, a series of mitigation measures have been identified to protect spacecraft from the existing debris population, and to minimize the future growth of objects in orbit. This paper outlines the current status of the environment and discusses some of the measures proposed.
{"title":"Orbital debris: a growing threat to space operations","authors":"R. Crowther","doi":"10.1098/rsta.2002.1118","DOIUrl":"https://doi.org/10.1098/rsta.2002.1118","url":null,"abstract":"The man–made orbital debris population is growing rapidly, dominating the meteoroid environment in all but the micrometre size range. Of most concern are objects between 1 cm and 10 cm, referred to as the lethal population as they cannot be tracked or catalogued and can cause catastrophic damage when colliding with a satellite. In order to address this problem, a series of mitigation measures have been identified to protect spacecraft from the existing debris population, and to minimize the future growth of objects in orbit. This paper outlines the current status of the environment and discusses some of the measures proposed.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75002853","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}
While the role of space plasma in forming the Earth's aurora and modifying the circulation of the upper atmosphere is well established, possible connections with the atmosphere at lower altitudes remain the subject of some controversy. Various nonlinear mechanisms have been proposed that could explain why such a small external forcing could have a relatively large effect. To enable us to assess future anthropogenic climate change, a much more complete understanding of all potentially relevant natural processes is essential. In this paper, many of the key processes are discussed with a view to developing a low-cost microsatellite mission to investigate them.
{"title":"Space plasma influences on the Earth's atmosphere","authors":"Neil Arnold","doi":"10.1098/rsta.2002.1114","DOIUrl":"https://doi.org/10.1098/rsta.2002.1114","url":null,"abstract":"While the role of space plasma in forming the Earth's aurora and modifying the circulation of the upper atmosphere is well established, possible connections with the atmosphere at lower altitudes remain the subject of some controversy. Various nonlinear mechanisms have been proposed that could explain why such a small external forcing could have a relatively large effect. To enable us to assess future anthropogenic climate change, a much more complete understanding of all potentially relevant natural processes is essential. In this paper, many of the key processes are discussed with a view to developing a low-cost microsatellite mission to investigate them.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80158704","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}
The current emphasis in the satellite industry is on replacing large satellite platforms with one or more smaller satellites, built at lower cost, yet able to accomplish similar mission objectives. However, it is recognized that such small satellites pose severe constraints on payload volume, mass and power. Thus, the power constraint of synthetic–aperture–radar (SAR) imaging is such that a microsatellite would seem inappropriate. The primary reason for the high–transmit–power requirement is that traditional SAR systems collect the backscatter. Thus, if the forward–scattered element is collected, then the resultant reduction in transmit–power could make it feasible for installation on a microsatellite. Based upon this principle, a novel method by which two microsatellites ‘fly’ in a specific formation to accomplish an SAR imaging mission, bistatically, is proposed. The satellites view a swath of 30 km (chosen to limit the amount of data), at a ground resolution of 30 m, from an altitude of 700 km. The transmitting satellite will be the ‘master’, with the receiver satellite ‘slaved’ off it for synchronization. Applications to a polar–ice–monitoring mission are discussed.
{"title":"A novel method for achieving SAR imaging by means of a microsatellite constellation","authors":"O. S. Mitchell, C. Underwood","doi":"10.1098/rsta.2002.1106","DOIUrl":"https://doi.org/10.1098/rsta.2002.1106","url":null,"abstract":"The current emphasis in the satellite industry is on replacing large satellite platforms with one or more smaller satellites, built at lower cost, yet able to accomplish similar mission objectives. However, it is recognized that such small satellites pose severe constraints on payload volume, mass and power. Thus, the power constraint of synthetic–aperture–radar (SAR) imaging is such that a microsatellite would seem inappropriate. The primary reason for the high–transmit–power requirement is that traditional SAR systems collect the backscatter. Thus, if the forward–scattered element is collected, then the resultant reduction in transmit–power could make it feasible for installation on a microsatellite. Based upon this principle, a novel method by which two microsatellites ‘fly’ in a specific formation to accomplish an SAR imaging mission, bistatically, is proposed. The satellites view a swath of 30 km (chosen to limit the amount of data), at a ground resolution of 30 m, from an altitude of 700 km. The transmitting satellite will be the ‘master’, with the receiver satellite ‘slaved’ off it for synchronization. Applications to a polar–ice–monitoring mission are discussed.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75925891","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}
J. M. Rees, Christopher R. Wilford, R. Moffett, Z. Dent, I. Mann
Geomagnetic field–line resonances may be identified via the use of cross–phase analysis of data from two closely spaced meridional ground–based magnetometer stations. It has been demonstrated that preprocessing of the data using a wavelet–based filter, chosen with regard to the variance of coefficients of the wavelet components, can be used to remove both low–frequency trend and large amplitude, localized structures, thus facilitating the selection of the eigenfrequency. We demonstrate that the dependence of the variance of coefficients on the wavelet level during a geomagnetic storm event is characteristically different from that obtained from data on a day associated with quiet geomagnetic activity. This suggests that the spectral nature of magnetic disturbances excited in the magnetosphere is dependent upon the level of geomagnetic activity.
{"title":"Analysis of magnetometer data using wavelet transforms","authors":"J. M. Rees, Christopher R. Wilford, R. Moffett, Z. Dent, I. Mann","doi":"10.1098/rsta.2002.1115","DOIUrl":"https://doi.org/10.1098/rsta.2002.1115","url":null,"abstract":"Geomagnetic field–line resonances may be identified via the use of cross–phase analysis of data from two closely spaced meridional ground–based magnetometer stations. It has been demonstrated that preprocessing of the data using a wavelet–based filter, chosen with regard to the variance of coefficients of the wavelet components, can be used to remove both low–frequency trend and large amplitude, localized structures, thus facilitating the selection of the eigenfrequency. We demonstrate that the dependence of the variance of coefficients on the wavelet level during a geomagnetic storm event is characteristically different from that obtained from data on a day associated with quiet geomagnetic activity. This suggests that the spectral nature of magnetic disturbances excited in the magnetosphere is dependent upon the level of geomagnetic activity.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87012038","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}
It is now feasible to construct highly capable ‘nanosatellites’ (i.e. sub–10 kg satellites) to provide cost–effective and rapid–response orbiting test vehicles for advanced space missions and technologies. The UK's first nanosatellite, SNAP–1—designed and built by Surrey Space Centre (SSC) and Surrey Satellite Technology Ltd (SSTL) staff — is an example of such a test vehicle: in this case, built with the primary objective of demonstrating that a sophisticated, fully agile nanosatellite can be constructed rapidly, and at very low cost, using an extension of the modular–COTS–based design philosophy pioneered by SSC for its microsatellites. SNAP–1 was successfully launched into orbit on 28 June 2000 from the Plesetsk Cosmodrome on board a Russian Cosmos rocket. It flew alongside a Russian Cospas–Sarsat satellite called Nadezhda, and an SSTL–built Chinese microsatellite, called Tsinghua–1. The first year of operations has been highly successful, with SNAP–1 becoming the first nanosatellite to have demonstrated full attitude and orbit control, via its miniature momentum–wheel–based attitude control system and its butane–propellant–based propulsion system. This paper reviews the initial results of the SNAP–1 mission.
{"title":"In-orbit results from the SNAP-1 nanosatellite and its future potential","authors":"C. Underwood, G. Richardson, J. Savignol","doi":"10.1098/rsta.2002.1123","DOIUrl":"https://doi.org/10.1098/rsta.2002.1123","url":null,"abstract":"It is now feasible to construct highly capable ‘nanosatellites’ (i.e. sub–10 kg satellites) to provide cost–effective and rapid–response orbiting test vehicles for advanced space missions and technologies. The UK's first nanosatellite, SNAP–1—designed and built by Surrey Space Centre (SSC) and Surrey Satellite Technology Ltd (SSTL) staff — is an example of such a test vehicle: in this case, built with the primary objective of demonstrating that a sophisticated, fully agile nanosatellite can be constructed rapidly, and at very low cost, using an extension of the modular–COTS–based design philosophy pioneered by SSC for its microsatellites. SNAP–1 was successfully launched into orbit on 28 June 2000 from the Plesetsk Cosmodrome on board a Russian Cosmos rocket. It flew alongside a Russian Cospas–Sarsat satellite called Nadezhda, and an SSTL–built Chinese microsatellite, called Tsinghua–1. The first year of operations has been highly successful, with SNAP–1 becoming the first nanosatellite to have demonstrated full attitude and orbit control, via its miniature momentum–wheel–based attitude control system and its butane–propellant–based propulsion system. This paper reviews the initial results of the SNAP–1 mission.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88807228","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}
S. Cowley, J. Davies, A. Grocott, H. Khan, M. Lester, K. McWilliams, S. Milan, G. Provan, P. Sandholt, J. Wild, T. Yeoman
The properties of the Earth's coupled magnetosphere–ionosphere system are dominated by its interaction with the solar–wind plasma, mediated by magnetic reconnection at the magnetopause interface. As a consequence, Earth's magnetospheric dynamics depend primarily on the concurrent orientation of the interplanetary magnetic field (IMF). We illustrate current understanding of the system through the results of a number of recent case studies and highlight the remaining issues. The discussion centres on flux–transfer events and substorms during intervals of southward IMF and magnetopause and tail processes during intervals of northward IMF. We emphasize the great diagnostic power of combined in situ and remote–sensing observations from space and on the ground.
{"title":"Solar–wind–magnetosphere–ionosphere interactions in the Earth's plasma environment","authors":"S. Cowley, J. Davies, A. Grocott, H. Khan, M. Lester, K. McWilliams, S. Milan, G. Provan, P. Sandholt, J. Wild, T. Yeoman","doi":"10.1098/rsta.2002.1112","DOIUrl":"https://doi.org/10.1098/rsta.2002.1112","url":null,"abstract":"The properties of the Earth's coupled magnetosphere–ionosphere system are dominated by its interaction with the solar–wind plasma, mediated by magnetic reconnection at the magnetopause interface. As a consequence, Earth's magnetospheric dynamics depend primarily on the concurrent orientation of the interplanetary magnetic field (IMF). We illustrate current understanding of the system through the results of a number of recent case studies and highlight the remaining issues. The discussion centres on flux–transfer events and substorms during intervals of southward IMF and magnetopause and tail processes during intervals of northward IMF. We emphasize the great diagnostic power of combined in situ and remote–sensing observations from space and on the ground.","PeriodicalId":20023,"journal":{"name":"Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80967080","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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