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Supermassive Primordial Black Holes for Nano-Hertz Gravitational Waves and High-redshift JWST Galaxies

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Research in Astronomy and Astrophysics 2024年第9期24卷 3-8页

作者： Hai-Long Huang Yong Cai Jun-Qian Jiang Jun Zhang Yun-Song Piao School of physical sciences University of Chinese Academy of Sciences Institute for Astrophysics School of Physics Zhengzhou University International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of Sciences Taiji Laboratory for Gravitational Wave Universe (Beijing/Hangzhou) University of Chinese Academy of Sciences School of Fundamental Physics and mathematical sciences Hangzhou Institute for Advanced Study UCAS Institute of Theoretical Physics Chinese Academy of Sciences

Recently, observational hints for supermassive black holes have been accumulating, prompting the question: Can primordial black holes（PBHs） be supermassive, particularly with masses M?10～9M⊙? A supercritical bubble,containing an inflating baby universe, that nucleated during inflation can evolve into a PBH in our observable universe. We find that when the inflaton slowly transitions past a neighboring vacuum, the nucleation rate of supercritical bubbles inevitably peaks, leading to a mass distribution of multiverse PBHs with a peak mass up to M?1011M⊙. Thus, our mechanism naturally provides a primordial origin for supermassive black holes.

关键词： (cosmology:) early universe (cosmology:) inflation (galaxies:) quasars: supermassive black holes

Dynamic kinetic stereodivergent transformations of propargylic ammonium salts via dual nickel and copper catalysis

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Chinese Chemical Letters 2024年第8期35卷 265-269页

作者： Ruilong Geng Lingzi Peng Chang Guo Hefei National Laboratory for physical sciences at the Microscale and department of Chemistry University of Science and Technology of ChinaHefei 230026China

The dynamic kinetic asymmetric transformation of racemic propargylic ammonium salts with prochiral aldimine esters through a stereodivergent propargylation is catalyzed by dual nickel and copper ***,a diverse range of optically activeα-quaternary amino esters were produced via C-N bond cleavage with high reaction efficiency and stereoselectivity(up to>99%ee).By selection of the appropriate pair-wise combination of catalyst configurational isomers,all four possible stereoisomers of the corresponding propargylation products are obtained in high yields with excellent regio-,diastereo-,and enantioselectiv-ities.

关键词： Stereodivergent propargylation Dual catalysis C-N bond cleavage Azaomethine ylides Internal propargylic ammonium salts Excellent stereoselectivity

Tighter sum uncertainty relations via(α,β,γ)weighted Wigner–Yanase–Dyson skew information

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Communications in Theoretical Physics 2024年第3期76卷 91-99页

作者： Cong Xu Zhaoqi Wu Shao-Ming Fei School of mathematical sciences Capital Normal UniversityBeijing 100048China department of Mathematics Nanchang UniversityNanchang 330031China Max-Planck-Institute for Mathematics in the sciences 04103 LeipzigGermany

We establish tighter uncertainty relations for arbitrary finite observables via(α,β,γ)weighted Wigner–Yanase–Dyson((α,β,γ)WWYD)skew *** results are also applicable to the(α,γ)weighted Wigner–Yanase–Dyson((α,γ)WWYD)skew information and the weighted Wigner–Yanase–Dyson(WWYD)skew *** also present tighter lower bounds for quantum channels and unitary channels via(α,β,γ)modified weighted Wigner–Yanase–Dyson((α,β,γ)MWWYD)skew *** examples are provided to illustrate the tightness of our uncertainty relations.

关键词： quantum channels (α,β,γ)WWYD skew information (α,β,γ)MWWYD skew information uncertainty relations

THE ABSENCE OF SINGULAR CONTINUOUS SPECTRUM FOR PERTURBED JACOBI OPERATORS

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Acta Mathematica Scientia 2024年第2期44卷 515-531页

作者：傅钲淇黎雄 department of Basic sciences Naval Submarine AcademyQingdao266199China Laboratory of Mathematics and Complex Systems(Ministry of Education) School of Mathematical SciencesBeijing Normal UniversityBeijing100875China

This paper is mainly about the spectral properties of a class of Jacobi operators(H_(c,b)u)(n)=c_(n)u(n+1)+c_(n-1)u(n-1)+b_(n)u(n),.where∣c_(n)−1∣=O(n^(−α))and b_(n)=O(n^(−1)).We will show that,forα≥1,the singula... 详细信息

关键词： Jacobi operator singular continuous spectrum Prüfer variables

Advances in bio-inspired electrocatalysts for clean energy future

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Nano Research 2024年第2期17卷 515-533页

作者： Jing-Wen Duan Mu Min-Rui Gao Division of Nanomaterials&Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleDepartment of ChemistryUniversity of Science and Technology of ChinaHefei 230026China

Electrocatalysis can enable efficient energy storage and conversion and thus is an effective way to achieve carbon *** unique structure and function of organisms can offer many ideas for the design of electrocatalysts,which has become one of the most promising research ***,the understanding of the mechanism of bio-inspired electrocatalysis has become clearer,which has promoted the design of bio-inspired catalysts and catalytic *** bio-inspired catalysts(enzyme-like catalysts,layered porous catalysts,superhydrophobic/superhydrophilic surfaces,and so on)have been developed to enable efficient electrocatalytic ***,we discuss the key advances in the field of bio-inspired electrocatalysts progressed in recent ***,the role of bio-inspiration in increasing the intrinsic activity and number of active sites of catalysts is ***,the structure and mechanism of layered porous catalytic systems that mimic biological transport systems are comprehensively ***,the design of three-phase interfaces from micro-nanoscale to atomic scale is highlighted,including the wettability of the electrode surface and the transport system near the *** conclude the review by identifying challenges in bio-inspired electrocatalysts and providing insights into future prospects for the exciting research field.

关键词： bio-inspired electrocatalysts active sites layered porous structure three-phase interface

A Local Macroscopic Conservative(LoMaC)Low Rank Tensor Method with the Discontinuous Galerkin Method for the Vlasov Dynamics

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Communications on Applied Mathematics and Computation 2024年第1期6卷 550-575页

作者： Wei Guo Jannatul Ferdous Ema Jing-Mei Qiu department of Mathematics and Statistics Texas Tech UniversityLubbockTX70409USA department of mathematical sciences University of DelawareNewarkDE19716USA

In this paper,we propose a novel Local Macroscopic Conservative(LoMaC)low rank tensor method with discontinuous Galerkin(DG)discretization for the physical and phase spaces for simulating the Vlasov-Poisson(VP)*** LoMaC property refers to the exact local conservation of macroscopic mass,momentum,and energy at the discrete *** recently developed LoMaC low rank tensor algorithm(arXiv:2207.00518)simultaneously evolves the macroscopic conservation laws of mass,momentum,and energy using the kinetic flux vector splitting;then the LoMaC property is realized by projecting the low rank kinetic solution onto a subspace that shares the same macroscopic *** paper is a generalization of our previous work,but with DG discretization to take advantage of its compactness and flexibility in handling boundary conditions and its superior accuracy in the long *** algorithm is developed in a similar fashion as that for a finite difference scheme,by observing that the DG method can be viewed equivalently in a nodal *** the nodal DG method,assuming a tensorized computational grid,one will be able to(i)derive differentiation matrices for different nodal points based on a DG upwind discretization of transport terms,and(ii)define a weighted inner product space based on the nodal DG grid *** algorithm can be extended to the high dimensional problems by hierarchical Tucker(HT)decomposition of solution tensors and a corresponding conservative projection *** a similar spirit,the algorithm can be extended to DG methods on nodal points of an unstructured mesh,or to other types of discretization,e.g.,the spectral method in velocity *** numerical results are performed to showcase the efficacy of the method.

关键词： Hierarchical Tucker(HT)decomposition Conservative SVD Energy conservation Discontinuous Galerkin(DG)method

Miyaoka-type inequalities for terminal threefolds with nef anti-canonical divisors

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Science China Mathematics 2024年

作者： Masataka Iwai Chen Jiang Haidong Liu department of Mathematics Graduate School of Science Osaka University Shanghai Center for mathematical sciences & School of mathematical sciences Fudan University department of mathematics Sun Yat-sen University

In this paper,we study Miyaoka-type inequalities on Chern classes of terminal projective 3-folds with nef anti-canonical *** X be a terminal projective 3-fold such that-KXis *** show that if c1（X）·c2（X）≠0,then c1（X）·c2（X）≥1/252;if further X is not rationally connected,then c1（X）·c2（X）≥4/5 and this inequality is *** order to prove this,we give a partial classification of such varieties along with many *** also study the nonvanishing of c1（X）dimX-2·c2（X） for terminal weak Fano varieties and prove a Miyaoka-Kawamata-type inequality.

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BIG HANKEL OPERATORS ON HARDY SPACES OF STRONGLY PSEUDOCONVEX DOMAINS

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Acta Mathematica Scientia 2024年第3期44卷 789-809页

作者：陈伯勇江良英 School of mathematical sciences Fudan UniversityShanghai200433China department of Statistics and Mathematics Shanghai Lixin University of Accounting and FinanceShanghai201209China

In this article,we investigate the(big) Hankel operator H_(f) on the Hardy spaces of bounded strongly pseudoconvex domains Ω in C^(n).We observe that H_(f ) is bounded on H~p(Ω)(1

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In this article,we investigate the(big) Hankel operator H_(f) on the Hardy spaces of bounded strongly pseudoconvex domains Ω in C^(n).We observe that H_(f ) is bounded on H~p(Ω)(1

关键词： Hankel operator Hardy space Bergman space pseudoconvex domain

Removing Splitting/Modeling Error in Projection/Penalty Methods for Navier-Stokes Simulations with Continuous Data Assimilation

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Communications in mathematical Research 2024年第1期40卷 1-29页

作者： Elizabeth Hawkins Leo G.Rebholz Duygu Vargun department of mathematical sciences Clemson UniversityClemsonSC 29634USA

We study continuous data assimilation(CDA)applied to projection and penalty methods for the Navier-Stokes(NS)*** and projection methods are more efficient than consistent Ns discretizations,however are less accurate due to modeling error(penalty)and splitting error(projection).We show analytically and numerically that with measurement data and properly chosen parameters,CDA can effectively remove these splitting and modeling errors and provide long time optimally accurate solutions.

关键词： Navier-Stokes equations projection method penalty method continuous data assimilation