Effects of 4-dimension variational data assimi-lation (4DVAR) with multifold observed data on the typhoontrack forecast are studied, by using the MM5V3 model, theRTTOVS-5 model and their adjoint models. The data usedf...Effects of 4-dimension variational data assimi-lation (4DVAR) with multifold observed data on the typhoontrack forecast are studied, by using the MM5V3 model, theRTTOVS-5 model and their adjoint models. The data usedfor assimilation include large-scale background fields data,bogus data, cloud-derived wind data, satellite inverse data,and high resolution infrared radiation sounder data (HIRS).There are 5 typhoon cases are used to perform the numericalexperiments and assimilation experiments. The numericalresults show that with 4DVAR the initial fields can be greatlyimproved and the initial typhoon structure can be clearlydescribed.展开更多
Summary of main observation and conclusion There are active debates on whether the concept of aromaticity should be exte nded bey ond carb on based organic systems. One argument against such extension is that the prop...Summary of main observation and conclusion There are active debates on whether the concept of aromaticity should be exte nded bey ond carb on based organic systems. One argument against such extension is that the proposed new aromatic species are not bottleable. We present herein in-depth chemical bonding analyses of a synthetic, core-shell, intermetalloid [Pd3Sn8Bi6]^4-.cluster. The computational data unravel unprecedented five-fold (π and σ) aromaticity, in cludi ng d-orbital aromaticity. Delocalized electr on clouds in this all-metal system cover the Pd3 core, trigonal pyramid Sn4 caps, peripheral Bi6 ring, and roof-like Sn2Bi2 walls, each following the (4n+2) Huckel rule. The present finding is beyond imagination, providing a compelling example that all-metal aromaticity not only exists in bulk compounds, but also can be in multifold π/σ fashion.展开更多
Following publication of the original article[1],the following information has been delete from the Acknowledgments section:KTL acknowledges the support of the Croucher Foundation,the Dr.Tai-chin Lo Foundation and the...Following publication of the original article[1],the following information has been delete from the Acknowledgments section:KTL acknowledges the support of the Croucher Foundation,the Dr.Tai-chin Lo Foundation and the HKRGC through grants C6026-16W,C6025-19G,16310219 and 16309718.The following information has been added to the Funding section:K.T.L.acknowledges the support of the Ministry of Science and Technology,China,and Hong Kong Research Grant Council throughGrantsNo.2020YFA0309600,No.RFS2021-6S03,No.C6025-19G,No.AoE/P-701/20,No.16310520,No.16310219,No.16307622,and No.16309718.展开更多
Recently,multifold fermions characterized by band crossings with multifold degeneracy and Fermi surfaces with higher Chern numbers have been discovered experimentally in AlPt(Schroter et al.in Nat Phys 15:759-765,2019...Recently,multifold fermions characterized by band crossings with multifold degeneracy and Fermi surfaces with higher Chern numbers have been discovered experimentally in AlPt(Schroter et al.in Nat Phys 15:759-765,2019)and XSi(X=Rh,Co)(Sanchez et al.in Nature 567:500-505,2019;Rao et al.in Nature 567:496-499,2019;Takane et al.in Phys Rev Lett 122:076402,2019).In this work,we largely expand the family of multifold fermion materials by pointing out that several well-studied noncentrosymmetric superconductors are indeed multifold fermion metals.Importantly,their normal state topological properties,which have been ignored in previous studies,play an important role in the superconducting properties.Taking Li_(2)Pd_(3)B and Li_(2)Pt_(3)B as examples,we found a large number of unconventional degenerate points,such as double spin-1,spin-3/2,Weyl and double Weyl topological band crossing points near the Fermi energy,which result in finite Chern numbers on Fermi surfaces.Long Fermi arc states in Li_(2)Pd_(3)B,originating from the nontrivial band topology were found.Importantly,it has been shown experimentally that Li_(2)Pd_(3)B and Li_(2)Pt_(3)B are fully gapped and gapless superconductors,respectively.By analyzing the possible pairing symmetries,we suggest that Li_(2)Pd_(3)B is a conventional s-wave superconductor or DIII class topological superconductor with Majorana surface states.Li_(2)Pt_(3)B,being gapless,is likely to be a nodal topological superconductor with dispersionless surface Majorana modes.We further identified that several noncentrosymmetric superconductors,such as Mo_(3)Al_(2)C,PdBiSe,Y_(2)C_(3)and La2C_(3),are multifold fermion superconductors.This work calls for a revisit for the study of noncentrosymmtric superconductors which provide platforms for investigating the interplay between superconductivity and topologically nontrivial Fermi surfaces.展开更多
文摘Effects of 4-dimension variational data assimi-lation (4DVAR) with multifold observed data on the typhoontrack forecast are studied, by using the MM5V3 model, theRTTOVS-5 model and their adjoint models. The data usedfor assimilation include large-scale background fields data,bogus data, cloud-derived wind data, satellite inverse data,and high resolution infrared radiation sounder data (HIRS).There are 5 typhoon cases are used to perform the numericalexperiments and assimilation experiments. The numericalresults show that with 4DVAR the initial fields can be greatlyimproved and the initial typhoon structure can be clearlydescribed.
基金the National Natural Science Foundation of China (Nos. 21873058, 21573138)the Sanjin Scholar Distinguished Professors Program.
文摘Summary of main observation and conclusion There are active debates on whether the concept of aromaticity should be exte nded bey ond carb on based organic systems. One argument against such extension is that the proposed new aromatic species are not bottleable. We present herein in-depth chemical bonding analyses of a synthetic, core-shell, intermetalloid [Pd3Sn8Bi6]^4-.cluster. The computational data unravel unprecedented five-fold (π and σ) aromaticity, in cludi ng d-orbital aromaticity. Delocalized electr on clouds in this all-metal system cover the Pd3 core, trigonal pyramid Sn4 caps, peripheral Bi6 ring, and roof-like Sn2Bi2 walls, each following the (4n+2) Huckel rule. The present finding is beyond imagination, providing a compelling example that all-metal aromaticity not only exists in bulk compounds, but also can be in multifold π/σ fashion.
文摘Following publication of the original article[1],the following information has been delete from the Acknowledgments section:KTL acknowledges the support of the Croucher Foundation,the Dr.Tai-chin Lo Foundation and the HKRGC through grants C6026-16W,C6025-19G,16310219 and 16309718.The following information has been added to the Funding section:K.T.L.acknowledges the support of the Ministry of Science and Technology,China,and Hong Kong Research Grant Council throughGrantsNo.2020YFA0309600,No.RFS2021-6S03,No.C6025-19G,No.AoE/P-701/20,No.16310520,No.16310219,No.16307622,and No.16309718.
基金support of the Ministry of Science and Technology,China,and Hong Kong Research Grant Council through Grants No.2020YFA0309600,No.RFS2021-6S03,No.C6025-19G,No.AoE/P-701/20,No.16310520,No.16310219,No.16307622,and No.16309718.
文摘Recently,multifold fermions characterized by band crossings with multifold degeneracy and Fermi surfaces with higher Chern numbers have been discovered experimentally in AlPt(Schroter et al.in Nat Phys 15:759-765,2019)and XSi(X=Rh,Co)(Sanchez et al.in Nature 567:500-505,2019;Rao et al.in Nature 567:496-499,2019;Takane et al.in Phys Rev Lett 122:076402,2019).In this work,we largely expand the family of multifold fermion materials by pointing out that several well-studied noncentrosymmetric superconductors are indeed multifold fermion metals.Importantly,their normal state topological properties,which have been ignored in previous studies,play an important role in the superconducting properties.Taking Li_(2)Pd_(3)B and Li_(2)Pt_(3)B as examples,we found a large number of unconventional degenerate points,such as double spin-1,spin-3/2,Weyl and double Weyl topological band crossing points near the Fermi energy,which result in finite Chern numbers on Fermi surfaces.Long Fermi arc states in Li_(2)Pd_(3)B,originating from the nontrivial band topology were found.Importantly,it has been shown experimentally that Li_(2)Pd_(3)B and Li_(2)Pt_(3)B are fully gapped and gapless superconductors,respectively.By analyzing the possible pairing symmetries,we suggest that Li_(2)Pd_(3)B is a conventional s-wave superconductor or DIII class topological superconductor with Majorana surface states.Li_(2)Pt_(3)B,being gapless,is likely to be a nodal topological superconductor with dispersionless surface Majorana modes.We further identified that several noncentrosymmetric superconductors,such as Mo_(3)Al_(2)C,PdBiSe,Y_(2)C_(3)and La2C_(3),are multifold fermion superconductors.This work calls for a revisit for the study of noncentrosymmtric superconductors which provide platforms for investigating the interplay between superconductivity and topologically nontrivial Fermi surfaces.
