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Dirac Quasinormal Modes of Static f(R) de Sitter Black Holes

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Communications in Theoretical Physics 2018年第2期69卷 179-187页

作者： hong ma Department of Physics Chongqing University Chongqing 401331 China

Quasinormal modes （QNMs） for Dirac perturbations off（R） black holes （BHs） are described in this paper, involving two types of f（R） solution： f（R）（Sehwarzschild） BHs and f（R）（maxwell） BHs. With the finite difference method, the stability of the f（R） black holes （BHs） is analysed and the threshold range off（R）（Schwarzschild） BHs and f（R）（maxwell） BHs is defined respectively. The results show that due to the presence of the correction factor Ro, the damping rate of Dirac field decreases. Meanwhile, the influence of angular quantum number values [k] on the f（R） BHs is investigated. The results indicate that the QNMs oscillation becomes tenser and damping speed slowly decreases with ]k[ increasing. Furthermore, under the Dirac perturbation, the stability off（R） solutions can be reflected in the manner of Dirac QNMs. The relationships between the QNMs and the parameters （]k], charge Q and mass m） are discussed in massless, and massive cases, by contrast to the classical BHs.

关键词： Dirae perturbation f(R) black holes quasinormal modes (QNMs)

Nuclear phylogenomics of angiosperms and insights into their relationships and evolution

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Journal of Integrative Plant Biology 2024年第3期66卷 546-578页

作者： Guojin Zhang hong ma College of Life Sciences Hunan Normal UniversityChangsha 410081China Department of Biology 510 Mueller LaboratoryHuck Institutes of the Life SciencesThe Pennsylvania State UniversityUniversity ParkPA 16802USA

Angiosperms(flowering plants) are by far the most diverse land plant group with over 300,000 species. The sudden appearance of diverse angiosperms in the fossil record was referred to by Darwin as the “abominable mystery,”hence contributing to the heightened interest in angiosperm evolution. Angiosperms display wide ranges of morphological, physiological,and ecological characters, some of which have probably influenced their species richness. The evolutionary analyses of these characteristics help to address questions of angiosperm diversification and require well resolved phylogeny. Following the great successes of phylogenetic analyses using plastid sequences,dozens to thousands of nuclear genes from next-generation sequencing have been used in angiosperm phylogenomic analyses, providing well resolved phylogenies and new insights into the evolution of angiosperms. In this review we focus on recent nuclear phylogenomic analyses of large angiosperm clades, orders, families,and subdivisions of some families and provide a summarized Nuclear Phylogenetic Tree of Angiosperm Families. The newly established nuclear phylogenetic relationships are highlighted and compared with previous phylogenetic results. The sequenced genomes of Amborella,Nymphaea, Chloranthus, Ceratophyllum, and species of monocots, magnoliids, and basal eudicots, have facilitated the phylogenomics of relationships among five major angiosperms clades. All but one of the 64 angiosperm orders were included in nuclear phylogenomics with well resolved relationships except the placements of several orders. Most families have been included with robust and highly supported placements, especially for relationships within several large and important orders and ***, we examine the divergence time estimation and biogeographic analyses of angiosperm on the basis of the nuclear phylogenomic frameworks and discuss the differences compared with previous analyses. Furthermore,we discuss the implicatio

关键词： angiosperms evolution flowering plants nuclear gene phylogenomics phylogeny

A Silver Cluster-Assembled material Showing Luminescent Mechanochromism and Thermochromism

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Chinese Journal of Chemistry 2019年第12期37卷 1287-1288页

作者： Xiao-hong ma College of Chemistry and Molecular Engineering Zhengzhou UniversityZhengzhouHenan 450001China

Silver chalcogenolate clusters(SCCs)[1]are a new category of materials with attractive photophysical ***,the notorious instability and the low emission quantum yield of SCCs hindered the profound investigation.

关键词： properties. Silver attractive

Finite Symmetry Transformation Groups and Exact Solutions of Lax Integrable Systems

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Communications in Theoretical Physics 2005年第2X期44卷 193-196页

作者： ma hong-Cai Physics Department Shanghai Jiao Tong University Shanghai 200030 China Physics Department Ningbo University Ningbo 315211 China mathematics Department Donghua University Shanghai 200051 China

The general Lie point symmetry groups of the Nizhnik-Novikov-Vesselov (NNV) equation and the asymmetric NNV equation are given by a simple direct method with help of their weak Lax pairs.

关键词： Lax pairs symmetries exact solution symmetry groups

Rotordynamic prediction of mode order transition when rotor has an overhang

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航空动力学报 2015年第2期30卷 397-409页

作者： Konstantin Shaposhnikov hong Jie ZHANG Da-yi ma Yan-hong School of Energy and Power Engineering Beijing University of Aeronautics and Astronautics

Nowadays rotating machinery grows and develops extremely fast due to its multi-branch *** the fields of rotordynamics and rotor balancing had a strong background based on previous experience in order to perform efficient and safe operation for the rotating machines,still there are problems which are hard to be dealt with in some special *** of them is balancing of the rotor with huge *** with overhang is inherent to have console modes,which previously often were observed separately from the other modes in rotordynamic *** such a way console modes,their behavior,order of appearance and interaction with other modes were described in current paper in more *** results confirmed that console modes obey the principle of orthogonality in the same way as all other modes and hence could be efficiently balanced using modal balancing *** results revealed likelihood of such phenomena as modes order transition,when the rotor has an *** a consequence perfectly balanced console rotor could not be so due to modes order transition effect when the bearing stiffness in situ differs from bearing stiffness of balancing *** results will be useful for engineers who are involved in area of rotating machinery vibration tuning for the rotor with huge overhang and benefit them to recognize these modes efficiently and to perform balancing successfully.

关键词：疲劳寿命分散性顺序统计量寿命分散系数小子样

Dirac quasinormal modes of Born-Infeld black hole spacetimes

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Chinese Physics C 2020年第9期44卷 175-185页

作者： hong ma Jin Li College of Physics and Electronic Information Engineering Qinghai Normal UniversityXining 810000China Joint Research Center for Physics Lanzhou University and Qinghai Normal UniversityXining810000China Department of Physics Chongqing UniversityChongqing 401331China

Quasinormal modes(QNMs)for massless and massive Dirac perturbations of Born-Infeld black holes(BHs)in higher dimensions are *** the corresponding master equation in accordance with hypergeometric functions and the QNMs are *** discuss the relationships between QNM frequencies and spacetime ***,we also discuss the stability of the Born-Infeld BH by calculating the temporal evolution of the perturbation *** the perturbation frequencies and the decay rate increase with increasing dimension of spacetime *** shows that the Born-Infeld BHs become more and more unstable at higher ***,the traditional finite difference method is improved,so that it can be used to calculate the massive Dirac *** also elucidate the dynamic evolution of Born-Infeld BHs in a massive Dirac *** the number of extra dimensions is related to the string scale,there is a relationship between the spacetime dimension n and the properties of Born-Infeld BHs that might be advantageous for the development of extra-dimensional brane worlds and string theory.

关键词： Dirac perturbation Born-Infeld black holes quasinormal modes(QNMs)

Gravitational quasinormal modes of static Einstein-Gauss-Bonnet anti-de Sitter black holes

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Chinese Physics C 2018年第4期42卷 188-197页

作者： hong ma Jin Li Department of Physics Chongqing University Chongqing 401331 China

In this paper, we describe quasinormal modes（QNMs） for gravitational perturbations of Einstein-GaussBonnet black holes（BHs） in higher dimensional spacetimes, and derive the corresponding parameters of such black holes in three types of spacetime（flat, de Sitter（d S） and anti-de Sitter（Ad S））. Our attention is concentrated on discussing the（in）stability of Einstein-Gauss-Bonnet Ad S BHs through the temporal evolution of all types of gravitational perturbation fields（tensor, vector and scalar）. It is concluded that the potential functions in vector and scalar gravitational perturbations have negative regions, which suppress quasinormal ringing. Furthermore,the influences of the Gauss-Bonnet coupling parameter α, the number of dimensions n and the angular momentum quantum number l on the Einstein-Gauss-Bonnet Ad S BHs quasinormal spectrum are analyzed. The QNM frequencies have greater oscillation and lower damping rate with the growth of α. This indicates that QNM frequencies become increasingly unstable with large α. Meanwhile, the dynamic evolutions of the perturbation field are compliant with the results of computation from the Horowitz and Hubeny method. Because the number of extra dimensions is connected with the string scale, the relationship between α and properties of Einstein-Gauss-Bonnet Ad S BHs might be beneficial for the exploitation of string theory and extra-dimensional brane worlds.

关键词： Einstein-Gauss-Bonnet AdS BHs gravitational perturbation quasinormal modes (QNMs)

Genome-wide Analysis of Kelch Repeatcontaining F-box Family

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Journal of Integrative Plant Biology 2007年第6期49卷 940-952页

作者： Yujin Sun Xiaofan Zhou hong ma Department of Biology and the Huck Institutes of Life Sciences Intercollege Graduate Program in Cell and Developmental Biology The Pennsylvania State University University Park PA 16802 USA

The ubiquitin-dependent protein degradation pathway plays diverse roles in eukaryotes. Previous studies indicate that both F-box and Kelch motifs are common in a variety of organisms. F-box proteins are subunits of E3 ubiquitin ligase complexes called SCFs （SKP1, Cullinl, F-box protein, and Rbxl）; they have an N-terminal F-box motif that binds to SKP1 （S-phase kinase associated protein）, and often have C-terminal protein-protein interaction domains, which specify the protein substrates for degradation via the ubiquitin pathway. One of the most frequently found protein interaction domains in F-box proteins is the Kelch repeat domain. Although both the F-box and Kelch repeats are ancient motifs, Kelch repeats-containing F-box proteins （KFB） have only been reported for human and Arabidopsis previously. The recent sequencing of the rice genome and other plant genomes provides an opportunity to examine the possible evolution history of KFB. We carried out extensive BLAST searches to identify putative KFBs in selected organisms, and analyzed their relationships phylogenetically. We also carried out the analysis of both gene duplication and gene expression of the KFBs in rice and Arabidopsis. Our study indicates that the origin of KFBs occurs before the divergence of animals and plants, and plant KFBs underwent rapid gene duplications.

关键词： Arabidopsis thaliana F-box motif Kelch repeats Kelch repeats-containing F-box proteins SCF SKP1 like.

Non-Lie Symmetry Groups of （2＋1）-Dimensional Nonlinear Systems

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Communications in Theoretical Physics 2006年第6X期46卷 1005-1010页

作者： ma hong-Cai LOU Sen-Yue Department of mathematics Donghua University Shanghai 200051 China Department of Physics Shanghai Jiao Tong University Shanghai 200030 China Center of Nonlinear Science Ningbo University Ningbo 315211 China

A modified direct method is developed to find finite symmetry groups of nonlinear mathematical physics systems. Applying the modified direct method to the well-known （2＋1）-dimensional asymmetric Nizhnik-Novikov-Vesselov equation and Nizhnik Novikov-Vesselov equation, both the Lie point symmetry groups and the non-Lie symmetry groups are obtained. The Lie symmetry groups obtained via traditional Lie approaches are only speciai cases. Furthermore, the expressions of the exact finite transformations of the Lie groups are much simpler than those obtained via the standard approaches.

关键词： symmetry groups CK direct method symmetries exact solution