A chain which is made to flow from a container, forms a striking arch that rises well above the container top. This phenomenon is caused by the well known Mould effect and is explained by a supply of momentum from the container, causing an upwards kick. Here we introduce a theory that allows for dynamic fluctuations of the chain and compare with corresponding simulations and experiments. The predictions for the chain velocity and fountain height agree well with experiments. We also explore the underlying mechanism for this momentum transfer for different chain models and find that it depends subtly on the nature of the chain as well as on the container.
{"title":"Dynamics of the Fluctuating Flying Chain","authors":"E. Flekkøy, M. Moura, K. Måløy","doi":"10.3389/fphy.2019.00187","DOIUrl":"https://doi.org/10.3389/fphy.2019.00187","url":null,"abstract":"A chain which is made to flow from a container, forms a striking arch that rises well above the container top. This phenomenon is caused by the well known Mould effect and is explained by a supply of momentum from the container, causing an upwards kick. Here we introduce a theory that allows for dynamic fluctuations of the chain and compare with corresponding simulations and experiments. The predictions for the chain velocity and fountain height agree well with experiments. We also explore the underlying mechanism for this momentum transfer for different chain models and find that it depends subtly on the nature of the chain as well as on the container.","PeriodicalId":49264,"journal":{"name":"Frontiers of Physics in China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3389/fphy.2019.00187","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44486036","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}
K. Rafique, M. Anwar, M. Misiran, I. Khan, S. Alharbi, P. Thounthong, K. Nisar
In this article, Casson Nanofluid boundary layer flow over non-straight slanted extending surface with Soret and Dufour impact scrutinized. Model used in this study is based on Buongiorno model for the thermal efficiencies of the fluid flows in the existence of Brownian motions and thermophoresis properties. The nonlinear problem for Casson Nanofluid flow over inclined channel is modeled to think about the heat and mass exchange phenomenon by considering portent flow parameters to intensified boundary layers. The overseeing nonlinear partial differential equations are changed to nonlinear ordinary differential equations and afterward illustrated numerically by methods for the Keller-Box conspire. A comparison of the established results in the lack of the incorporated effects is performed with the available outcomes of Khan and Pop [1] and recognized in a nice settlement. Numerical and graphical results are also presented in tables and graphs.
{"title":"Keller-Box Scheme for Casson Nanofluid Flow over Nonlinear Inclined Surface with Soret and Dufour Effects","authors":"K. Rafique, M. Anwar, M. Misiran, I. Khan, S. Alharbi, P. Thounthong, K. Nisar","doi":"10.3389/FPHY.2019.00139","DOIUrl":"https://doi.org/10.3389/FPHY.2019.00139","url":null,"abstract":"In this article, Casson Nanofluid boundary layer flow over non-straight slanted extending surface with Soret and Dufour impact scrutinized. Model used in this study is based on Buongiorno model for the thermal efficiencies of the fluid flows in the existence of Brownian motions and thermophoresis properties. The nonlinear problem for Casson Nanofluid flow over inclined channel is modeled to think about the heat and mass exchange phenomenon by considering portent flow parameters to intensified boundary layers. The overseeing nonlinear partial differential equations are changed to nonlinear ordinary differential equations and afterward illustrated numerically by methods for the Keller-Box conspire. A comparison of the established results in the lack of the incorporated effects is performed with the available outcomes of Khan and Pop [1] and recognized in a nice settlement. Numerical and graphical results are also presented in tables and graphs.","PeriodicalId":49264,"journal":{"name":"Frontiers of Physics in China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74947353","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}
{"title":"Editorial: Proceedings of the International School on Magnetic Resonance and Brain Function – XII Workshop","authors":"F. Giove, I. Ronen","doi":"10.3389/fphy.2018.00018","DOIUrl":"https://doi.org/10.3389/fphy.2018.00018","url":null,"abstract":"","PeriodicalId":49264,"journal":{"name":"Frontiers of Physics in China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3389/fphy.2018.00018","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43018311","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}
Editorial: Applications of Quantum Mechanical Techniques to Areas Outside of Quantum Mechanics
社论：量子力学技术在量子力学以外领域的应用
{"title":"Editorial: Applications of Quantum Mechanical Techniques to Areas Outside of Quantum Mechanics","authors":"E. Haven, A. Khrennikov","doi":"10.3389/FPHY.2017.00060","DOIUrl":"https://doi.org/10.3389/FPHY.2017.00060","url":null,"abstract":"Editorial: Applications of Quantum Mechanical Techniques to Areas Outside of Quantum Mechanics","PeriodicalId":49264,"journal":{"name":"Frontiers of Physics in China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3389/FPHY.2017.00060","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47558605","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}
{"title":"Corrigendum: Ultra-High Field NMR and MRI–The Role of Magnet Technology to Increase Sensitivity and Specificity","authors":"E. Moser, E. Laistler, F. Schmitt, G. Kontaxis","doi":"10.3389/fphy.2017.00041","DOIUrl":"https://doi.org/10.3389/fphy.2017.00041","url":null,"abstract":"","PeriodicalId":49264,"journal":{"name":"Frontiers of Physics in China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3389/fphy.2017.00041","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41387738","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. Orzada, A. Bitz, S. Johst, M. Gratz, Maximilian N. Völker, O. Kraff, A. Abuelhaija, Thomas M. Fiedler, K. Solbach, H. Quick, M. Ladd
Object In this work an 8-channel array integrated into the gap between the gradient coil and bore liner of a 7-Tesla whole-body magnet is presented that would allow a workflow closer to that of systems at lower magnetic fields that have a built-in body coil; this integrated coil is compared to a local 8-channel array built from identical elements placed directly on the patient. Materials and Methods SAR efficiency and the homogeneity of the right-rotating B1 field component (B_1^+) are investigated numerically and compared to the local array. Power efficiency measurements are performed in the MRI System. First in vivo gradient echo images are acquired with the integrated array. Results While the remote array shows a slightly better performance in terms of B_1^+ homogeneity, the power efficiency and the SAR efficiency are inferior to those of the local array: the transmit voltage has to be increased by a factor of 3.15 to achieve equal flip angles in a central axial slice. The g-factor calculations show a better parallel imaging g-factor for the local array. The field of view of the integrated array is larger than that of the local array. First in vivo images with the integrated array look subjectively promising. Conclusion Although some RF performance parameters of the integrated array are inferior to a tight-fitting local array, these disadvantages might be compensated by the use of amplifiers with higher power and the use of local receive arrays. In addition, the distant placement provides the potential to include more elements in the array design.
{"title":"Analysis of an Integrated 8-Channel Tx/Rx Body Array for Use as a Body Coil in 7-Tesla MRI","authors":"S. Orzada, A. Bitz, S. Johst, M. Gratz, Maximilian N. Völker, O. Kraff, A. Abuelhaija, Thomas M. Fiedler, K. Solbach, H. Quick, M. Ladd","doi":"10.3389/fphy.2017.00017","DOIUrl":"https://doi.org/10.3389/fphy.2017.00017","url":null,"abstract":"Object In this work an 8-channel array integrated into the gap between the gradient coil and bore liner of a 7-Tesla whole-body magnet is presented that would allow a workflow closer to that of systems at lower magnetic fields that have a built-in body coil; this integrated coil is compared to a local 8-channel array built from identical elements placed directly on the patient. Materials and Methods SAR efficiency and the homogeneity of the right-rotating B1 field component (B_1^+) are investigated numerically and compared to the local array. Power efficiency measurements are performed in the MRI System. First in vivo gradient echo images are acquired with the integrated array. Results While the remote array shows a slightly better performance in terms of B_1^+ homogeneity, the power efficiency and the SAR efficiency are inferior to those of the local array: the transmit voltage has to be increased by a factor of 3.15 to achieve equal flip angles in a central axial slice. The g-factor calculations show a better parallel imaging g-factor for the local array. The field of view of the integrated array is larger than that of the local array. First in vivo images with the integrated array look subjectively promising. Conclusion Although some RF performance parameters of the integrated array are inferior to a tight-fitting local array, these disadvantages might be compensated by the use of amplifiers with higher power and the use of local receive arrays. In addition, the distant placement provides the potential to include more elements in the array design.","PeriodicalId":49264,"journal":{"name":"Frontiers of Physics in China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3389/fphy.2017.00017","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45840165","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. Chappell, J. Hartnett, Nicolangelo Iannella, A. Iqbal, D. Abbott
The proper description of time remains a key unsolved problem in science. Newton conceived of time as absolute and universal which {it `flows equably without relation to anything external'}. In the nineteenth century, the four-dimensional algebraic structure of the quaternions developed by Hamilton, inspired him to suggest that they could provide a unified representation of space and time. With the publishing of Einstein's theory of special relativity these ideas then lead to the generally accepted Minkowski spacetime formulation in 1908. Minkowski, though, rejected the formalism of quaternions suggested by Hamilton and adopted rather an approach using four-vectors. The Minkowski framework is indeed found to provide a versatile formalism for describing the relationship between space and time in accordance with Einstein's relativistic principles, but nevertheless fails to provide more fundamental insights into the nature of time itself. In order to answer this question we begin by exploring the geometric properties of three-dimensional space that we model using Clifford geometric algebra, which is found to contain sufficient complexity to provide a natural description of spacetime. This description using Clifford algebra is found to provide a natural alternative to the Minkowski formulation as well as providing new insights into the nature of time. Our main result is that time is the scalar component of a Clifford space and can be viewed as an intrinsic geometric property of three-dimensional space without the need for the specific addition of a fourth dimension.
{"title":"Time As a Geometric Property of Space","authors":"J. M. Chappell, J. Hartnett, Nicolangelo Iannella, A. Iqbal, D. Abbott","doi":"10.3389/fphy.2016.00044","DOIUrl":"https://doi.org/10.3389/fphy.2016.00044","url":null,"abstract":"The proper description of time remains a key unsolved problem in science. Newton conceived of time as absolute and universal which {it `flows equably without relation to anything external'}. In the nineteenth century, the four-dimensional algebraic structure of the quaternions developed by Hamilton, inspired him to suggest that they could provide a unified representation of space and time. With the publishing of Einstein's theory of special relativity these ideas then lead to the generally accepted Minkowski spacetime formulation in 1908. Minkowski, though, rejected the formalism of quaternions suggested by Hamilton and adopted rather an approach using four-vectors. The Minkowski framework is indeed found to provide a versatile formalism for describing the relationship between space and time in accordance with Einstein's relativistic principles, but nevertheless fails to provide more fundamental insights into the nature of time itself. In order to answer this question we begin by exploring the geometric properties of three-dimensional space that we model using Clifford geometric algebra, which is found to contain sufficient complexity to provide a natural description of spacetime. This description using Clifford algebra is found to provide a natural alternative to the Minkowski formulation as well as providing new insights into the nature of time. Our main result is that time is the scalar component of a Clifford space and can be viewed as an intrinsic geometric property of three-dimensional space without the need for the specific addition of a fourth dimension.","PeriodicalId":49264,"journal":{"name":"Frontiers of Physics in China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3389/fphy.2016.00044","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69647688","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}
Employing the fermion unification model based on the intrinsic SU(8) symmetry of a generalized Dirac equation, we discuss the fundamental interactions under the SU(8)=SU(2)$otimes$SU(4) symmetry group. The physics involved can describe all fermions, the leptons (electron and neutrino), and the coloured up and down quarks of the first generation in the standard model (SM) by a complex SU(8) octet of Dirac spinor fields. The fermion interactions are found to be mediated by the unified SU(4) and SU(2) vector gauge boson fields, which include the photon, the gluons, and the bosons $Z$ and $W$ as well known from the SM, but also comprise new ones, namely three coloured $X$ bosons carrying a fractional hypercharge of $pm4/3$ and transmuting leptons into quarks and vice versa. The full covariant derivative of the model is derived and discussed. The Higgs mechanism gives mass to the $Z$ and $W$ bosons, but also permits one to derive the mass of the coloured $X$ boson, for which depending on the choice of the values of the coupling constant, the estimates are 35~GeV or 156~GeV, values that are well within reach of the LHC. The scalar Higgs field can also lend masses to the fermions and fix their physical values for given appropriate coupling constants to that field.
{"title":"Fundamental Fermion Interactions via Vector Bosons of Unified SU(2)⊗SU(4) Gauge Fields","authors":"E. Marsch, Y. Narita","doi":"10.3389/fphy.2016.00005","DOIUrl":"https://doi.org/10.3389/fphy.2016.00005","url":null,"abstract":"Employing the fermion unification model based on the intrinsic SU(8) symmetry of a generalized Dirac equation, we discuss the fundamental interactions under the SU(8)=SU(2)$otimes$SU(4) symmetry group. The physics involved can describe all fermions, the leptons (electron and neutrino), and the coloured up and down quarks of the first generation in the standard model (SM) by a complex SU(8) octet of Dirac spinor fields. The fermion interactions are found to be mediated by the unified SU(4) and SU(2) vector gauge boson fields, which include the photon, the gluons, and the bosons $Z$ and $W$ as well known from the SM, but also comprise new ones, namely three coloured $X$ bosons carrying a fractional hypercharge of $pm4/3$ and transmuting leptons into quarks and vice versa. The full covariant derivative of the model is derived and discussed. The Higgs mechanism gives mass to the $Z$ and $W$ bosons, but also permits one to derive the mass of the coloured $X$ boson, for which depending on the choice of the values of the coupling constant, the estimates are 35~GeV or 156~GeV, values that are well within reach of the LHC. The scalar Higgs field can also lend masses to the fermions and fix their physical values for given appropriate coupling constants to that field.","PeriodicalId":49264,"journal":{"name":"Frontiers of Physics in China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3389/fphy.2016.00005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69647595","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 : 2016-01-01DOI: 10.3389/CONF.FPHY.2016.01.00004
S. Filip, Lampinen Bjrn, Nilsson Markus
{"title":"Apparent Exchange Rate and Isotropic and Anisotropic Kurtosis in Meningioma and Glioma Tumors","authors":"S. Filip, Lampinen Bjrn, Nilsson Markus","doi":"10.3389/CONF.FPHY.2016.01.00004","DOIUrl":"https://doi.org/10.3389/CONF.FPHY.2016.01.00004","url":null,"abstract":"","PeriodicalId":49264,"journal":{"name":"Frontiers of Physics in China","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69550401","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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